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Wiki source code of 07 Adjustments

Version 29.5 by Karen on 2023/05/15 16:11
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1 = **Overview** =
2
3 The servo drive needs to make the motor faithfully operate in accordance with the instructions issued by the upper controller without delay as much as possible. In order to make the motor action closer to the instruction and maximize the mechanical performance, gain adjustment is required. The process of gain adjustment is shown in Figure 7-1.
4
5 (% style="text-align:center" %)
6 (((
7 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
8 [[**Figure 7-1 Gain adjustment process**>>image:image-20220608174118-1.png||id="Iimage-20220608174118-1.png"]]
9 )))
10
11 The servo gain is composed of multiple sets of parameters such as position loop, speed loop, filter, load inertia ratio, etc., and they affect each other. In the process of setting the servo gain, the balance between the setting values of each parameter must be considered.
12
13 (% class="box infomessage" %)
14 (((
15 ✎**Note: **Before adjusting the gain, it is recommended to perform a jog trial run first to ensure that the servo motor can operate normally! The gain adjustment process description is shown in the table below.
16 )))
17
18 (% class="table-bordered" style="margin-right:auto" %)
19 |=(% colspan="3" style="text-align: center; vertical-align: middle;" %)**Gain adjustment process**|=(% style="text-align: center; vertical-align: middle;" %)**Function**|=(% style="text-align: center; vertical-align: middle;" %)**Detailed chapter**
20 |(% style="text-align:center; vertical-align:middle" %)1|(% colspan="2" style="text-align:center; vertical-align:middle" %)Online inertia recognition|(% style="text-align:center; vertical-align:middle" %)Use the host computer debugging platform software matched with the drive to automatically identify the load inertia ratio. With its own inertia identification function, the drive automatically calculates the load inertia ratio.|(% style="text-align:center; vertical-align:middle" %)__[[7.2>>||anchor="HInertiarecognition"]]__
21 |(% style="text-align:center; vertical-align:middle" %)2|(% colspan="2" style="text-align:center; vertical-align:middle" %)Automatic gain adjustment|On the premise of setting the inertia ratio correctly, the drive automatically adjusts a set of matching gain parameters.|(% style="text-align:center; vertical-align:middle" %)__[[7.3.1>>||anchor="HAutomaticgainadjustment"]]__
22 |(% rowspan="2" style="text-align:center; vertical-align:middle" %)3|(% rowspan="2" style="text-align:center; vertical-align:middle" %)Manual gain adjustment|(% style="text-align:center; vertical-align:middle" %)Basic gain|On the basis of automatic gain adjustment, if the expected effect is not achieved, manually fine-tune the gain to optimize the effect.|(% style="text-align:center; vertical-align:middle" %)__[[7.3.2>>||anchor="HManualgainadjustment"]]__
23 |(% style="text-align:center; vertical-align:middle" %)Feedforward gain|The feedforward function is enabled to improve the followability.|(% style="text-align:center; vertical-align:middle" %)__[[7.3.3>>||anchor="HFeedforwardgain"]]__
24 |(% style="text-align:center; vertical-align:middle" %)4|(% style="text-align:center; vertical-align:middle" %)Vibration suppression|(% style="text-align:center; vertical-align:middle" %)Mechanical resonance|The notch filter function is enabled to suppress mechanical resonance.|(% style="text-align:center; vertical-align:middle" %)__[[7.4.1>>||anchor="HMechanicalresonancesuppressionmethods"]]__
25
26 Table 7-1 Description of gain adjustment process
27
28 = **Inertia recognition** =
29
30 Load inertia ratio P03-01 refers to:
31
32 (% style="text-align:center" %)
33 [[image:image-20220611152902-1.png||class="img-thumbnail"]]
34
35 The load inertia ratio is an important parameter of the servo system, and setting of the load inertia ratio correctly helps to quickly complete the debugging. The load inertia ratio could be set manually, and online load inertia recognition could be performed through the host computer debugging software.
36
37 (% class="warning" %)|(((
38 (% style="text-align:center" %)
39 [[image:image-20220611152918-2.png]]
40 )))
41 |(((
42 **Before performing online load inertia recognition, the following conditions should be met:**
43
44 * The maximum speed of the motor should be greater than 300rpm;
45 * The actual load inertia ratio is between 0.00 and 100.00;
46 * The load torque is relatively stable, and the load cannot change drastically during the measurement process;
47 * The backlash of the load transmission mechanism is within a certain range;
48
49 **The motor's runable stroke should meet two requirements:**
50
51 * There is a movable stroke of more than 1 turn in both forward and reverse directions between the mechanical limit switches.
52 * Before performing online inertia recognition, please make sure that the limit switch has been installed on the machine, and that the motor has a movable stroke of more than 1 turn each in the forward and reverse directions to prevent overtravel during the inertia recognition process and cause accidents.
53 * Meet the requirement of inertia recognition turns P03-05.
54 * Make sure that the motor's runable stroke at the stop position is greater than the set value of the number of inertia recognition circles P03-05, otherwise the maximum speed of inertia recognition P03-06 should be appropriately reduced.
55 * During the automatic load inertia recognition process, if vibration occurs, the load inertia recognition should be stopped immediately.
56 )))
57
58 The related function codes are shown in the table below.
59
60 (% class="table-bordered" %)
61 |=(% scope="row" style="text-align: center; vertical-align: middle; width: 117px;" %)**Function code**|=(% style="text-align: center; vertical-align: middle; width: 136px;" %)**Name**|=(% style="text-align: center; vertical-align: middle; width: 173px;" %)(((
62 **Setting method**
63 )))|=(% style="text-align: center; vertical-align: middle; width: 168px;" %)(((
64 **Effective time**
65 )))|=(% style="text-align: center; vertical-align: middle; width: 125px;" %)**Default value**|=(% style="text-align: center; vertical-align: middle; width: 118px;" %)**Range**|=(% style="text-align: center; vertical-align: middle; width: 276px;" %)**Definition**|=(% style="text-align: center; vertical-align: middle;" %)**Unit**
66 |=(% style="text-align: center; vertical-align: middle; width: 117px;" %)P03-01|(% style="text-align:center; vertical-align:middle; width:136px" %)Load inertia ratio|(% style="text-align:center; vertical-align:middle; width:173px" %)(((
67 Operation setting
68 )))|(% style="text-align:center; vertical-align:middle; width:168px" %)(((
69 Effective immediately
70 )))|(% style="text-align:center; vertical-align:middle; width:125px" %)300|(% style="text-align:center; vertical-align:middle; width:118px" %)100 to 10000|(% style="width:276px" %)Set load inertia ratio, 0.00 to 100.00 times|(% style="text-align:center; vertical-align:middle" %)0.01
71 |=(% style="text-align: center; vertical-align: middle; width: 117px;" %)P03-05|(% style="text-align:center; vertical-align:middle; width:136px" %)(((
72 Inertia recognition turns
73 )))|(% style="text-align:center; vertical-align:middle; width:173px" %)(((
74 Shutdown setting
75 )))|(% style="text-align:center; vertical-align:middle; width:168px" %)(((
76 Effective immediately
77 )))|(% style="text-align:center; vertical-align:middle; width:125px" %)2|(% style="text-align:center; vertical-align:middle; width:118px" %)1 to 20|(% style="width:276px" %)Offline load inertia recognition process, motor rotation number setting|(% style="text-align:center; vertical-align:middle" %)circle
78 |=(% style="text-align: center; vertical-align: middle; width: 117px;" %)P03-06|(% style="text-align:center; vertical-align:middle; width:136px" %)(((
79 Inertia recognition maximum speed
80 )))|(% style="text-align:center; vertical-align:middle; width:173px" %)(((
81 Shutdown setting
82 )))|(% style="text-align:center; vertical-align:middle; width:168px" %)(((
83 Effective immediately
84 )))|(% style="text-align:center; vertical-align:middle; width:125px" %)1000|(% style="text-align:center; vertical-align:middle; width:118px" %)300 to 2000|(% style="width:276px" %)(((
85 Set the allowable maximum motor speed instruction in offline inertia recognition mode.
86
87 The faster the speed during inertia recognition, the more accurate the recognition result will be. Usually, you can keep the default value.
88 )))|(% style="text-align:center; vertical-align:middle" %)rpm
89 |=(% style="text-align: center; vertical-align: middle; width: 117px;" %)P03-07|(% style="text-align:center; vertical-align:middle; width:136px" %)(((
90 Parameter recognition rotation direction
91 )))|(% style="text-align:center; vertical-align:middle; width:173px" %)(((
92 Shutdown setting
93 )))|(% style="text-align:center; vertical-align:middle; width:168px" %)(((
94 Effective immediately
95 )))|(% style="text-align:center; vertical-align:middle; width:125px" %)0|(% style="text-align:center; vertical-align:middle; width:118px" %)0 to 2|(% style="width:276px" %)(((
96 0: Forward and reverse reciprocating rotation
97
98 1: Forward one-way rotation
99
100 2: Reverse one-way rotation
101 )))|(% style="text-align:center; vertical-align:middle" %)-
102
103 Table 7-2 Related parameters of gain adjustment
104
105 = **Gain adjustment** =
106
107 In order to optimize the responsiveness of the servo drive, the servo gain set in the servo drive needs to be adjusted. Servo gain needs to set multiple parameter combinations, which will affect each other. Therefore, the adjustment of servo gain must consider the relationship between each parameter.
108
109 Under normal circumstances, high-rigidity machinery can improve the response performance by increasing the servo gain. But for machines with lower rigidity, when the servo gain is increased, vibration may occur, and then affects the increase in gain. Therefore, selecting appropriate servo gain parameters can achieve higher response and stable performance.
110
111 The servo supports automatic gain adjustment and manual gain adjustment. It is recommended to use automatic gain adjustment first.
112
113 == Automatic gain adjustment ==
114
115 Automatic gain adjustment means that through the rigidity level selection function P03-02, the servo drive will automatically generate a set of matching gain parameters to meet the requirements of rapidity and stability.
116
117 The rigidity of the servo refers to the ability of the motor rotor to resist load inertia, that is, the self-locking ability of the motor rotor. The stronger the servo rigidity, the larger the corresponding position loop gain and speed loop gain, and the faster the response speed of the system.
118
119 (% class="table-bordered" style="margin-right:auto" %)
120 (% class="warning" %)|(% style="text-align:center; vertical-align:middle" %)[[image:image-20220611152630-1.png]]
121 |(% style="text-align:left; vertical-align:middle" %)Before adjusting the rigidity grade, set the appropriate load inertia ratio P03-01 correctly.
122
123 The value range of the rigidity grade is between 0 and 31. Grade 0 corresponds to the weakest rigidity and minimum gain, and grade 31 corresponds to the strongest rigidity and maximum gain. According to different load types, the values in the table below are for reference.
124
125 (% class="table-bordered" %)
126 |=(% scope="row" style="text-align: center; vertical-align: middle;" %)**Rigidity grade**|=(% style="text-align: center; vertical-align: middle;" %)**Load mechanism type**
127 |=(% style="text-align: center; vertical-align: middle;" %)Grade 4 to 8|(% style="text-align:center; vertical-align:middle" %)Some large machinery
128 |=(% style="text-align: center; vertical-align: middle;" %)Grade 8 to 15|(% style="text-align:center; vertical-align:middle" %)Low rigidity applications such as belts
129 |=(% style="text-align: center; vertical-align: middle;" %)Grade 15 to 20|(% style="text-align:center; vertical-align:middle" %)High rigidity applications such as ball screw and direct connection
130
131 Table 7-3 Experience reference of rigidity grade
132
133 When the function code P03-03 is set to 0, the gain parameters are stored in the first gain by modifying the rigidity grade.
134
135 When debugging with the host computer debugging software, automatic rigidity level measurement can be carried out, which is used to select a set of appropriate rigidity grades as operating parameters. The operation steps are as follows:
136
137 * Step1 Confirm that the servo is in the ready state, the panel displays “rdy”, and the communication line is connected;
138 * Step2 Open the host computer debugging software, enter the trial run interface, set the corresponding parameters, and click "Servo on";
139 * Step3 Click the "forward rotation" or "reverse rotation" button to confirm the travel range of the servo operation;
140 * Step4 After the "start recognition" of inertia recognition lights up, click "start recognition" to perform inertia recognition, and the load inertia can be measured.
141 * Step5 After the inertia recognition test is completed, click "Save Inertia Value";
142 * Step6 Click "Next" at the bottom right to go to the parameter adjustment interface, and click "Parameter measurement" to start parameter measurement.
143 * Step7 After the parameter measurement is completed, the host computer debugging software will pop up a confirmation window for parameter writing and saving.
144
145 (% class="table-bordered" %)
146 (% class="warning" %)|(% style="text-align:center; vertical-align:middle" %)[[image:image-20220611152634-2.png]]
147 |(((
148 ✎There may be a short mechanical whistling sound during the test. Generally, the servo will automatically stop the test. If it does not stop automatically or in other abnormal situations, you can click the "Servo Off" button on the interface to turn off the servo, or power off the machine!
149
150 ✎For the detailed operation of the host computer debugging software, please refer to "Wecon Servo Debugging Platform User Manual".
151 )))
152
153 (% class="table-bordered" %)
154 |=(% scope="row" style="text-align: center; vertical-align: middle; width: 84px;" %)**Function code**|=(% style="text-align: center; vertical-align: middle; width: 138px;" %)**Name**|=(% style="text-align: center; vertical-align: middle; width: 103px;" %)(((
155 **Setting method**
156 )))|=(% style="text-align: center; vertical-align: middle; width: 105px;" %)(((
157 **Effective time**
158 )))|=(% style="text-align: center; vertical-align: middle; width: 87px;" %)**Default value**|=(% style="text-align: center; vertical-align: middle; width: 83px;" %)**Range**|=(% style="text-align: center; vertical-align: middle; width: 431px;" %)**Definition**|=(% style="text-align: center; vertical-align: middle;" %)**Unit**
159 |=(% style="text-align: center; vertical-align: middle; width: 84px;" %)P03-03|(% style="text-align:center; vertical-align:middle; width:138px" %)Self-adjusting mode selection|(% style="text-align:center; vertical-align:middle; width:103px" %)(((
160 Operation setting
161 )))|(% style="text-align:center; vertical-align:middle; width:105px" %)(((
162 Effective immediately
163 )))|(% style="text-align:center; vertical-align:middle; width:87px" %)0|(% style="text-align:center; vertical-align:middle; width:83px" %)0 to 2|(% style="width:431px" %)(((
164 * 0: Rigidity grade self-adjusting mode. Position loop gain, speed loop gain, speed loop integral time constant, torque filter parameter settings are automatically adjusted according to the rigidity grade setting.
165 * 1: Manual setting; you need to manually set the position loop gain, speed loop gain, speed loop integral time constant, torque filter parameter setting
166 * 2: Online automatic parameter self-adjusting mode (Not implemented yet)
167 )))|(% style="text-align:center; vertical-align:middle" %)-
168
169 Table 7-4 Details of self-adjusting mode selection parameters
170
171 == Manual gain adjustment ==
172
173 When the servo automatic gain adjustment fails to achieve the desired result, you can manually fine-tune the gain to achieve better results.
174
175 The servo system consists of three control loops, from the outside to the inside are the position loop, the speed loop and the current loop. The basic control block diagram is shown as below.
176
177 (% style="text-align:center" %)
178 (((
179 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
180 [[**Figure 7-2 Basic block diagram of servo loop gain**>>image:image-20220608174209-2.png||id="Iimage-20220608174209-2.png"]]
181 )))
182
183 The more the inner loop is, the higher the responsiveness is required. Failure to comply with this principle may lead to system instability!
184
185 The default current loop gain of the servo drive has ensured sufficient responsiveness. Generally, no adjustment is required. Only the position loop gain, speed loop gain and other auxiliary gains need to be adjusted.
186
187 This servo drive has two sets of gain parameters for position loop and speed loop. The user can switch the two sets of gain parameters according to the setting value of P02-07 the 2nd gain switching mode. The parameters are below.
188
189 (% class="table-bordered" %)
190 |=(% scope="row" style="text-align: center; vertical-align: middle; width: 450px;" %)**Function code**|=(% style="text-align: center; vertical-align: middle; width: 751px;" %)**Name**
191 |=(% style="text-align: center; vertical-align: middle; width: 450px;" %)P02-01|(% style="width:751px" %)The 1st position loop gain
192 |=(% style="text-align: center; vertical-align: middle; width: 450px;" %)P02-02|(% style="width:751px" %)The 1st speed loop gain
193 |=(% style="text-align: center; vertical-align: middle; width: 450px;" %)P02-03|(% style="width:751px" %)The 1st speed loop integral time constant
194 |=(% style="text-align: center; vertical-align: middle; width: 450px;" %)P02-04|(% style="width:751px" %)The 2nd position loop gain
195 |=(% style="text-align: center; vertical-align: middle; width: 450px;" %)P02-05|(% style="width:751px" %)The 2nd speed loop gain
196 |=(% style="text-align: center; vertical-align: middle; width: 450px;" %)P02-06|(% style="width:751px" %)The 2nd speed loop integral time constant
197 |=(% style="text-align: center; vertical-align: middle; width: 450px;" %)P04-04|(% style="width:751px" %)Torque filter time constant
198
199 **Speed loop gain**
200
201 In the case of no vibration or noise in the mechanical system, the larger the speed loop gain setting value, the better the response of servo system and the better the speed followability. When noise occurs in the system, reduce the speed loop gain. The related function codes are shown as below.
202
203 (% class="table-bordered" %)
204 |=(% scope="row" style="text-align: center; vertical-align: middle; width: 120px;" %)**Function code**|=(% style="text-align: center; vertical-align: middle; width: 163px;" %)**Name**|=(% style="text-align: center; vertical-align: middle; width: 122px;" %)(((
205 **Setting method**
206 )))|=(% style="text-align: center; vertical-align: middle; width: 128px;" %)(((
207 **Effective time**
208 )))|=(% style="text-align: center; vertical-align: middle; width: 103px;" %)**Default value**|=(% style="text-align: center; vertical-align: middle; width: 107px;" %)**Range**|=(% style="text-align: center; vertical-align: middle; width: 321px;" %)**Definition**|=(% style="text-align: center; vertical-align: middle;" %)**Unit**
209 |=(% style="text-align: center; vertical-align: middle; width: 120px;" %)P02-02|(% style="text-align:center; vertical-align:middle; width:163px" %)1st speed loop gain|(% style="text-align:center; vertical-align:middle; width:122px" %)(((
210 Operation setting
211 )))|(% style="text-align:center; vertical-align:middle; width:128px" %)(((
212 Effective immediately
213 )))|(% style="text-align:center; vertical-align:middle; width:103px" %)65|(% style="text-align:center; vertical-align:middle; width:107px" %)0 to 35000|(% style="width:321px" %)Set speed loop proportional gain to determine the responsiveness of speed loop.|(% style="text-align:center; vertical-align:middle" %)0.1Hz
214 |=(% style="text-align: center; vertical-align: middle; width: 120px;" %)P02-05|(% style="text-align:center; vertical-align:middle; width:163px" %)2nd speed loop gain|(% style="text-align:center; vertical-align:middle; width:122px" %)(((
215 Operation setting
216 )))|(% style="text-align:center; vertical-align:middle; width:128px" %)(((
217 Effective immediately
218 )))|(% style="text-align:center; vertical-align:middle; width:103px" %)65|(% style="text-align:center; vertical-align:middle; width:107px" %)0 to 35000|(% style="width:321px" %)Set speed loop proportional gain to determine the responsiveness of speed loop.|(% style="text-align:center; vertical-align:middle" %)0.1Hz
219
220 Table 7-5 Speed loop gain parameters
221
222 (% style="text-align:center" %)
223 (((
224 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
225 [[**Figure 7-3 Speed loop gain effect illustration**>>image:image-20220706152743-1.jpeg||id="Iimage-20220706152743-1.jpeg"]]
226 )))
227
228 **Speed loop integral time constant**
229
230 The speed loop integral time constant is used to eliminate the speed loop deviation. Decreasing the integral time constant of the speed loop can increase the speed of the speed following. If the set value is too small, is will easily cause speed overshoot or vibration. When the time constant is set too large, the integral action will be weakened, resulting in a deviation of the speed loop. Related function codes are shown as below.
231
232 (% class="table-bordered" %)
233 |=(% scope="row" style="text-align: center; vertical-align: middle; width: 98px;" %)**Function code**|=(% style="text-align: center; vertical-align: middle; width: 173px;" %)**Name**|=(% style="text-align: center; vertical-align: middle; width: 122px;" %)(((
234 **Setting method**
235 )))|=(% style="text-align: center; vertical-align: middle; width: 112px;" %)(((
236 **Effective time**
237 )))|=(% style="text-align: center; vertical-align: middle; width: 109px;" %)**Default value**|=(% style="text-align: center; vertical-align: middle; width: 114px;" %)**Range**|=(% style="text-align: center; vertical-align: middle; width: 278px;" %)**Definition**|=(% style="text-align: center; vertical-align: middle; width: 78px;" %)**Unit**
238 |=(% style="text-align: center; vertical-align: middle; width: 98px;" %)P02-03|(% style="text-align:center; vertical-align:middle; width:173px" %)(((
239 1st speed loop integral time constant
240 )))|(% style="text-align:center; vertical-align:middle; width:122px" %)(((
241 Operation setting
242 )))|(% style="text-align:center; vertical-align:middle; width:112px" %)(((
243 Effective immediately
244 )))|(% style="text-align:center; vertical-align:middle; width:109px" %)1000|(% style="text-align:center; vertical-align:middle; width:114px" %)100 to 65535|(% style="width:278px" %)Set the speed loop integral constant. The smaller the set value, the stronger the integral effect.|(% style="text-align:center; vertical-align:middle; width:78px" %)(((
245 0.1ms
246 )))
247 |=(% style="text-align: center; vertical-align: middle; width: 98px;" %)P02-06|(% style="text-align:center; vertical-align:middle; width:173px" %)(((
248 2nd speed loop integral time constant
249 )))|(% style="text-align:center; vertical-align:middle; width:122px" %)(((
250 Operation setting
251 )))|(% style="text-align:center; vertical-align:middle; width:112px" %)(((
252 Effective immediately
253 )))|(% style="text-align:center; vertical-align:middle; width:109px" %)1000|(% style="text-align:center; vertical-align:middle; width:114px" %)0 to 65535|(% style="width:278px" %)Set the speed loop integral constant. The smaller the set value, the stronger the integral effect.|(% style="text-align:center; vertical-align:middle; width:78px" %)(((
254 0.1ms
255 )))
256
257 Table 7-6 Speed loop integral time constant parameters
258
259 (% style="text-align:center" %)
260 (((
261 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
262 [[**Figure 7-4 Speed loop integral time constant effect illustration**>>image:image-20220706153140-2.jpeg||id="Iimage-20220706153140-2.jpeg"]]
263 )))
264
265 **Position loop gain**
266
267 Determine the highest frequency of the position instruction that the position loop can follow the change. Increasing this parameter can speed up the positioning time and improve the ability of the motor to resist external disturbances when the motor is stationary. However, if the setting value is too large, the system may be unstable and oscillate. The related function codes are shown as below.
268
269 (% class="table-bordered" %)
270 |=(% scope="row" style="text-align: center; vertical-align: middle; width: 95px;" %)**Function code**|=(% style="text-align: center; vertical-align: middle; width: 174px;" %)**Name**|=(% style="text-align: center; vertical-align: middle; width: 120px;" %)(((
271 **Setting method**
272 )))|=(% style="text-align: center; vertical-align: middle; width: 114px;" %)(((
273 **Effective time**
274 )))|=(% style="text-align: center; vertical-align: middle; width: 79px;" %)**Default value**|=(% style="text-align: center; vertical-align: middle; width: 91px;" %)**Range**|=(% style="text-align: center; vertical-align: middle; width: 355px;" %)**Definition**|=(% style="text-align: center; vertical-align: middle;" %)**Unit**
275 |=(% style="text-align: center; vertical-align: middle; width: 95px;" %)P02-01|(% style="text-align:center; vertical-align:middle; width:174px" %)1st position loop gain|(% style="text-align:center; vertical-align:middle; width:120px" %)(((
276 Operation setting
277 )))|(% style="text-align:center; vertical-align:middle; width:114px" %)(((
278 Effective immediately
279 )))|(% style="text-align:center; vertical-align:middle; width:79px" %)400|(% style="text-align:center; vertical-align:middle; width:91px" %)0 to 6200|(% style="width:355px" %)Set position loop proportional gain to determine the responsiveness of position control system.|(% style="text-align:center; vertical-align:middle" %)0.1Hz
280 |=(% style="text-align: center; vertical-align: middle; width: 95px;" %)P02-04|(% style="text-align:center; vertical-align:middle; width:174px" %)2nd position loop gain|(% style="text-align:center; vertical-align:middle; width:120px" %)(((
281 Operation setting
282 )))|(% style="text-align:center; vertical-align:middle; width:114px" %)(((
283 Effective immediately
284 )))|(% style="text-align:center; vertical-align:middle; width:79px" %)35|(% style="text-align:center; vertical-align:middle; width:91px" %)0 to 6200|(% style="width:355px" %)Set position loop proportional gain to determine the responsiveness of position control system.|(% style="text-align:center; vertical-align:middle" %)0.1Hz
285
286 Table 7-7 Position loop gain parameters
287
288 (% style="text-align:center" %)
289 (((
290 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
291 [[**Figure 7-5 Position loop gain effect illustration**>>image:image-20220706153656-3.jpeg||id="Iimage-20220706153656-3.jpeg"]]
292 )))
293
294 **Torque instruction filter time**
295
296 Selecting an appropriate torque filter time constant could suppress mechanical resonance. The larger the value of this parameter, the stronger the suppression ability. If the setting value is too large, it will decrease the current loop response frequency and cause needle movement. The related function codes are shown as below.
297
298 (% class="table-bordered" %)
299 |=(% scope="row" style="text-align: center; vertical-align: middle; width: 117px;" %)**Function code**|=(% style="text-align: center; vertical-align: middle; width: 200px;" %)**Name**|=(% style="text-align: center; vertical-align: middle; width: 120px;" %)(((
300 **Setting method**
301 )))|=(% style="text-align: center; vertical-align: middle; width: 127px;" %)(((
302 **Effective time**
303 )))|=(% style="text-align: center; vertical-align: middle; width: 79px;" %)**Default value**|=(% style="text-align: center; vertical-align: middle; width: 371px;" %)**Definition**|=(% style="text-align: center; vertical-align: middle;" %)**Unit**
304 |=(% style="text-align: center; vertical-align: middle; width: 117px;" %)P04-04|(% style="text-align:center; vertical-align:middle; width:200px" %)Torque filter time constant|(% style="text-align:center; vertical-align:middle; width:120px" %)(((
305 Operation setting
306 )))|(% style="text-align:center; vertical-align:middle; width:127px" %)(((
307 Effective immediately
308 )))|(% style="text-align:center; vertical-align:middle; width:79px" %)50|(% style="width:371px" %)This parameter is automatically set when “self-adjustment mode selection” is selected as 1 or 2|(% style="text-align:center; vertical-align:middle" %)0.01ms
309
310 Table 7-8 Details of torque filter time constant parameters
311
312 == **Feedforward gain** ==
313
314 Speed feedforward could be used in position control mode and full closed-loop function. It could improve the response to the speed instruction and reduce the position deviation with fixed speed.
315
316 Speed feedforward parameters are shown in __Table 7-9__. Torque feedforward parameters are shown in __Table 7-10__.
317
318 Torque feedforward could improve the response to the torque instruction and reduce the position deviation with fixed acceleration and deceleration.
319
320 (% class="table-bordered" %)
321 |=(% scope="row" style="text-align: center; vertical-align: middle; width: 125px;" %)**Function code**|=(% style="text-align: center; vertical-align: middle; width: 330px;" %)**Name**|=(% style="text-align: center; vertical-align: middle; width: 746px;" %)**Adjustment description**
322 |=(% style="text-align: center; vertical-align: middle; width: 125px;" %)P02-09|(% style="text-align:center; vertical-align:middle; width:330px" %)Speed feedforward gain|(% rowspan="2" style="width:746px" %)(((
323 When the speed feedforward filter is set to 50 (0.5 ms), gradually increase the speed feedforward gain, and the speed feedforward will take effect. The position deviation during operation at a certain speed will be reduced according to the value of speed feedforward gain as the formula below.
324
325 Position deviation (instruction unit) = instruction speed[instruction unit/s]÷position loop gain [1/s]×(100－speed feedforward gain [%])÷100
326 )))
327 |=(% style="text-align: center; vertical-align: middle; width: 125px;" %)P02-10|(% style="text-align:center; vertical-align:middle; width:330px" %)Speed feedforward filtering time constant
328
329 Table 7-9 Speed feedforward parameters
330
331 (% style="text-align:center" %)
332 (((
333 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
334 [[**Figure 7-6 Speed feedforward parameters effect illustration**>>image:image-20220706155307-4.jpeg||height="119" id="Iimage-20220706155307-4.jpeg" width="835"]]
335 )))
336
337
338 (% class="table-bordered" %)
339 |=(% scope="row" style="text-align: center; vertical-align: middle; width: 125px;" %)**Function code**|=(% style="text-align: center; vertical-align: middle; width: 259px;" %)**Name**|=(% style="text-align: center; vertical-align: middle; width: 690px;" %)**Adjustment description**
340 |=(% style="text-align: center; vertical-align: middle; width: 125px;" %)P02-11|(% style="text-align:center; vertical-align:middle; width:259px" %)Torque feedforward gain|(% rowspan="2" style="width:690px" %)Increase the torque feedforward gain because the position deviation can be close to 0 during certain acceleration and deceleration. Under the ideal condition of external disturbance torque not operating, when driving in the trapezoidal speed model, the position deviation can be close to 0 in the entire action interval. In fact, there must be external disturbance torque, so the position deviation cannot be zero. In addition, like the speed feedforward, although the larger the constant of the torque feedforward filter, the smaller the action sound, but the greater the position deviation of the acceleration change point.
341 |=(% style="text-align: center; vertical-align: middle; width: 125px;" %)P02-12|(% style="text-align:center; vertical-align:middle; width:259px" %)Torque feedforward filtering time constant
342
343 Table 7-10 Torque feedforward parameters
344
345 == **Model Tracking Control Function** ==
346
347 Model tracking control is suitable for position control mode, which adds a model loop outside the three loops. In the model loop, new position commands, speed feedforward and torque feedforward and other control quantities are generated according to the user's response requirements to the system and the ideal motor control model. Applying these control quantities to the actual control loop can significantly improve the response performance and positioning performance of the position control, the design block diagram is as follows:
348
349 (% style="text-align:center" %)
350 (((
351 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
352 [[**Figure 7-7 Block Diagram of Model Tracking Control Design**>>image:20230515-7.png||height="394" id="20230515-7.png" width="931"]]
353 )))
354
355 The usage method and conditions of model tracking control:
356
357 ~1. Correctly set the inertia ratio of the system P3-1, which can be obtained by monitoring the real-time load inertia ratio of U0-20.
358
359 2. Set the load rigidity level P3-2, set an appropriate value, it does not need to set a high rigidity level (recommended value 17~~21 under rigid load).
360
361 3. Set P2-20=1 to enable the function of model tracking control.
362
363 4. Adjust the P2-21 model tracking control gain from small to large, and gradually increase in steps of 1000 until the responsiveness of the system meets the actual demand. The responsiveness of the system is mainly determined by this parameter.
364
365 5. After the responsiveness meets the requirements, user can adjust the parameters appropriately to increase the load rigidity level P3-2.
366
367 (% class="box infomessage" %)
368 (((
369 **✎Note**: Model tracking control is only available in position mode, and cannot be used in other modes.
370 )))
371
372 (% class="table-bordered" %)
373 |=(% scope="row" style="text-align: center; vertical-align: middle; width: 120px;" %)**Function code**|=(% style="text-align: center; vertical-align: middle; width: 163px;" %)**Name**|=(% style="text-align: center; vertical-align: middle; width: 122px;" %)(((
374 **Setting method**
375 )))|=(% style="text-align: center; vertical-align: middle; width: 128px;" %)(((
376 **Effective time**
377 )))|=(% style="text-align: center; vertical-align: middle; width: 103px;" %)**Default value**|=(% style="text-align: center; vertical-align: middle; width: 107px;" %)**Range**|=(% style="text-align: center; vertical-align: middle; width: 321px;" %)**Definition**|=(% style="text-align: center; vertical-align: middle;" %)**Unit**
378 |=(% style="text-align: center; vertical-align: middle; width: 120px;" %)P2-20|(% style="text-align:center; vertical-align:middle; width:163px" %)Model tracking control function|(% style="text-align:center; vertical-align:middle; width:122px" %)(((
379 Shutdown setting
380 )))|(% style="text-align:center; vertical-align:middle; width:128px" %)(((
381 Effective immediately
382 )))|(% style="text-align:center; vertical-align:middle; width:103px" %)0|(% style="text-align:center; vertical-align:middle; width:107px" %)0 to 1|When the function code is set to 1, enable the model tracking control function.|
383 |=(% style="text-align: center; vertical-align: middle; width: 120px;" %)P2-21|(% style="text-align:center; vertical-align:middle; width:163px" %)Model tracking control gain|(% style="text-align:center; vertical-align:middle; width:122px" %)(((
384 Shutdown setting
385 )))|(% style="text-align:center; vertical-align:middle; width:128px" %)(((
386 Effective immediately
387 )))|(% style="text-align:center; vertical-align:middle; width:103px" %)1000|(% style="text-align:center; vertical-align:middle; width:107px" %)200 to 20000|(% rowspan="2" style="width:321px" %)Increasing the model tracking control gain can improve the position response performance of the model loop. If the gain is too high, it may cause overshoot behavior. The gain compensation affects the damping ratio of the model loop, and the damping ratio becomes larger as the gain compensation becomes larger.|(% style="text-align:center; vertical-align:middle" %)0.1/s
388 |=(% style="text-align: center; vertical-align: middle; width: 120px;" %)P2-22|(% style="text-align:center; vertical-align:middle; width:163px" %)Model tracking control gain compensation|(% style="text-align:center; vertical-align:middle; width:122px" %)(((
389 Shutdown setting
390 )))|(% style="text-align:center; vertical-align:middle; width:128px" %)(((
391 Effective immediately
392 )))|(% style="text-align:center; vertical-align:middle; width:103px" %)1000|(% style="text-align:center; vertical-align:middle; width:107px" %)500 to 2000|(% style="text-align:center; vertical-align:middle" %)0.10%
393
394 (% class="table-bordered" %)
395 |=(% scope="row" style="text-align: center; vertical-align: middle; width: 120px;" %)**Function code**|=(% style="text-align: center; vertical-align: middle; width: 163px;" %)**Name**|=(% style="text-align: center; vertical-align: middle; width: 122px;" %)(((
396 **Setting method**
397 )))|=(% style="text-align: center; vertical-align: middle; width: 128px;" %)(((
398 **Effective time**
399 )))|=(% style="text-align: center; vertical-align: middle; width: 103px;" %)**Default value**|=(% style="text-align: center; vertical-align: middle; width: 107px;" %)**Range**|=(% style="text-align: center; vertical-align: middle; width: 321px;" %)**Definition**|=(% style="text-align: center; vertical-align: middle;" %)**Unit**
400 |=(% style="text-align: center; vertical-align: middle; width: 120px;" %)P2-23|(% style="text-align:center; vertical-align:middle; width:163px" %)Model tracking control forward rotation bias|(((
401 Operation setting
402 )))|(% style="text-align:center; vertical-align:middle; width:128px" %)(((
403 Effective immediately
404 )))|(% style="text-align:center; vertical-align:middle; width:103px" %)1000|(% style="text-align:center; vertical-align:middle; width:107px" %)0 to 10000|(% rowspan="2" %)(% style="width:321px" %)Torque feedforward size in the positive and reverse direction under model tracking control|(% style="text-align:center; vertical-align:middle" %)0.10%
405 |=(% style="text-align: center; vertical-align: middle; width: 120px;" %)P2-24|(% style="text-align:center; vertical-align:middle; width:163px" %)Model tracking control reverses rotation bias|(((
406 Operation setting
407 )))|(% style="text-align:center; vertical-align:middle; width:128px" %)(((
408 Effective immediately
409 )))|(% style="text-align:center; vertical-align:middle; width:103px" %)1000|(% style="text-align:center; vertical-align:middle; width:107px" %)0 to 10000|(% style="text-align:center; vertical-align:middle" %)0.10%
410 |=(% style="text-align: center; vertical-align: middle; width: 120px;" %)P2-25|(% style="text-align:center; vertical-align:middle; width:163px" %)Model tracking control speed feedforward compensation|Operation setting|(% style="text-align:center; vertical-align:middle; width:128px" %)(((
411 Effective immediately
412 )))|(% style="text-align:center; vertical-align:middle; width:103px" %)1000|(% style="text-align:center; vertical-align:middle; width:107px" %)0 to 10000|(% style="width:321px" %)The size of the speed feedforward under model tracking control|(% style="text-align:center; vertical-align:middle" %)0.10%
413
414 Please refer to the following for an example of the procedure of adjusting servo gain.
415
416 (% style="width:1508px" %)
417 |=(% style="text-align:center; vertical-align:middle; width:80px" %)**Step**|=(% style="text-align:center; vertical-align:middle; width:1420px" %)**Content**
418 |=(% style="text-align: center; vertical-align: middle; width: 80px;" %)1|Please try to set the correct load inertia ratio parameter P3-1.
419 |=(% style="text-align:center; vertical-align:middle; width:80px" %)2|If the automatic adjustment mode is used (P3-3 is set to 0), please set the basic rigidity level parameter P3-2. If in manual adjustment mode (P3-3 is set to 1), please set the gain P2-1~~P2-3 related to the position loop and speed loop and the torque filter time constant P4-4. The setting principle is mainly no vibration and overshoot.
420 |=(% style="text-align: center; vertical-align: middle; width: 80px;" %)3|Turn on the model tracking function, set P2-20 to 1.
421 |=(% style="text-align: center; vertical-align: middle; width: 80px;" %)4|Increase the model tracking gain P2-21 within the range of no overshoot and vibration occurring.
422 |=(% style="text-align: center; vertical-align: middle; width: 80px;" %)5|If the rigidity level of step 2 is set relatively low, user can properly increase the rigidity level P3-2.
423 |=(% style="text-align: center; vertical-align: middle; width: 80px;" %)6|When overshoot occurs, or the responses of forward rotation and reverse rotation are different, user can fine-tune through model tracking control forward bias P2-23, model tracking control reverse bias P2-24, model tracking control speed feedforward compensation P2 -25.
424
425 == **Gain switching** ==
426
427 **Gain switching function:**
428
429 ● Switch to a lower gain in the motor stationary (servo enabled)state to suppress vibration;
430
431 ● Switch to a higher gain in the motor stationary state to shorten the positioning time;
432
433 ● Switch to a higher gain in the motor running state to get better command tracking performance;
434
435 ● Switch different gain settings by external signals depending on the load connected.
436
437 **Gain switching parameter setting**
438
439 ①When P02-07=0
440
441 Fixed use of the first gain (using P02-01~~P02-03), and the switching of P/PI (proportional/proportional integral) control could be realized through DI function 10 (GAIN-SEL, gain switching).
442
443 (% style="text-align:center" %)
444 (((
445 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
446 [[image:20230515-8.png||height="378" id="20230515-8.png" width="363"]]
447 )))
448
449 ② When P02-07=1
450
451 The switching conditions can be set through parameter P02-08 to realize switching between the first gain (P02-01~~P02-03) and the second gain (P02-04~~P02-06).
452
453 (% style="text-align:center" %)
454 (((
455 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
456 [[**Figure 7-9 Flow chart of gain switching when P02-07=1**>>image:20230515-9.png||id="20230515-9.png"]]
457 )))
458
459 |=(% style="text-align:center; vertical-align:middle; width:72px" %)**P02-08**|=(% style="text-align:center; vertical-align:middle; width:146px" %)**Content**|=(% style="text-align:center; vertical-align:middle; width:72px" %)**Diagram**
460 |=(% style="text-align:center; vertical-align:middle;width:72px" %)0|(% style="text-align:center; vertical-align:middle; width:146px" %)Fixed use of the first gain|~-~-
461 |(% style="text-align:center; vertical-align:middle;width:72px" %)1|(% style="text-align:center; vertical-align:middle;width:146px" %)Switching with DI|~-~-
462 |=(% style="text-align:center; vertical-align:middle;width:72px" %)(((
463
464
465
466
467
468
469 2
470 )))|(% style="text-align:center; vertical-align:middle;width:146px" %)(((
471
472
473
474
475
476
477 Large torque command
478 )))|[[image:image-20230515140641-1.png]]
479 |=(% style="text-align:center; vertical-align:middle;width:72px" %)(((
480
481
482
483
484
485
486
487 3
488 )))|(% style="text-align:center; vertical-align:middle;width:146px" %)Large actual torque|[[image:image-20230515140641-2.png]]
489 |=(% style="text-align:center; vertical-align:middle;width:72px" %)(((
490
491
492
493
494
495
496 4
497 )))|(% style="width:146px" %)(((
498
499
500
501
502
503
504 Large speed command
505 )))|[[image:image-20230515140641-3.png]]
506
507 |(% style="width:74px" %)**P02-08**|(% style="width:176px" %)**Content**|**Diagram**
508 |=(% style="width:74px" %)(((
509
510
511
512
513
514 5
515 )))|(% style="width:176px" %)(((
516
517
518
519
520
521 Fast actual speed
522 )))|(((
523
524
525 [[image:image-20230515140641-4.png]]
526 )))
527 |=(% style="width:74px" %)(((
528
529
530
531
532
533
534
535 6
536 )))|(% style="width:176px" %)(((
537
538
539
540
541
542
543
544 Speed command change rate is large
545 )))|[[image:image-20230515140641-5.png]]
546 |=(% style="width:74px" %)(((
547
548
549
550
551
552
553 7
554
555
556 )))|(% style="width:176px" %)(((
557
558
559
560
561
562
563 Large position deviation
564 )))|[[image:image-20230515140641-6.png]]
565 |=(% style="width:74px" %)(((
566
567
568
569
570
571 8
572 )))|(% style="width:176px" %)(((
573
574
575
576
577
578 Position command
579 )))|[[image:image-20230515140641-7.png]]
580
581 |=(% style="width:73px" %)(((
582
583
584
585
586
587
588 9
589 )))|(% style="width:154px" %)(((
590
591
592
593
594
595
596 Positioning completed
597 )))|[[image:image-20230515140641-8.png]]
598 |=(% style="width:73px" %)(((
599
600
601 10
602
603
604 )))|(% style="width:154px" %)(((
605
606
607 Position command + actual speed
608 )))|(((
609
610
611 Refer to the chart below
612 )))
613
614 (% style="text-align:center" %)
615 [[image:20230515-10.png]]
616
617 Figure 7-10 P02-08=10 Position command + actual speed gain description
618
619 Description of related parameters
620
621 |(% rowspan="2" style="width:68px" %)
622 **P02-07**|(% style="width:150px" %)**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
623 |(% style="width:150px" %)The second gain switching mode|Operation setting|Effective immediately|0|0 to 1|Gain control|
624 |(% colspan="8" %)(((
625 Set the switching mode of the second gain.
626
627 |**Setting value**|**Function**
628 |0|(((
629 The first gain is used by default. Switching using DI function 10 (GAIN-SEL, gain switching):
630
631 DI logic invalid: PI control;
632
633 DI logic valid: PI control.
634 )))
635 |1|The first gain and the second gain are switched by the setting value of P02-08.
636 )))
637
638 |(% rowspan="2" %)
639 **P02-08**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
640 |Gain switching condition selection|Operation setting|Effective immediately|0|0 to 10|Gain control|
641 |(% colspan="8" %)(((
642 Set the conditions for gain switching.
643
644 |Setting value|Gain switching conditions|Details
645 |0|The default is the first gain|Fixed use of the first gain
646 |1|Switch by DI port|(((
647 Use DI function 10 (GAIN-SEL, gain switching);
648
649 DI logic is invalid: the first gain (P02-01~~P02-03);
650
651 DI logic is valid: the second gain (P02-04~~P02-06).
652 )))
653 |2|Large torque command|(((
654 In the previous first gain, when the absolute value of torque command is greater than (grade + hysteresis), the second gain is switched;
655
656 In the previous second gain, when the absolute value of torque command is less than the value of (grade - hysteresis) and the duration is greater than [P02-13], the first gain is returned.
657
658
659 )))
660 |3|Large actual torque|(((
661 In the previous first gain, when the absolute value of actual torque is greater than ( grade + hysteresis ), the second gain is switched;
662
663 In the previous second gain, when the absolute value of actual torque is less than the value of (grade - hysteresis) and the duration is greater than [P02-13], the first gain is returned .
664
665
666 )))
667 |4|Large speed command|(((
668 In the previous first gain, when the absolute value of speed command is greater than (grade + hysteresis), the second gain is switched;
669
670 In the previous second gain, when the absolute value of speed command is less than the value of (grade - hysteresis) and the duration is greater than [P02-13], the first gain is returned .
671
672
673 )))
674 |5|Large actual speed|(((
675 In the previous first gain, when the absolute value of actual speed is greater than (grade + hysteresis), the second gain is switched;
676
677 In the previous second gain, when the absolute value of actual speed is less than the value of (grade - hysteresis) and the duration is greater than [P02-13], the first gain is returned .
678
679
680 )))
681 |(((
682
683
684 6
685 )))|(((
686
687
688 Large rate of change in speed command
689 )))|(((
690 In the previous first gain, when the absolute value of the rate of change in speed command is greater than (grade + hysteresis), the second gain is switched;
691
692 In the previous second gain, switch to the first gain when the absolute value of the rate of change in speed command is less than the value of (grade - hysteresis) and the duration is greater than [P02-13], the first gain is returned .
693
694
695 )))
696 |(((
697
698
699 7
700 )))|(((
701
702
703 Large position deviation
704 )))|(((
705 In the previous first gain, when the absolute value of position deviation is greater than (grade + hysteresis), the second gain is switched;
706
707 In the previous second gain, switch to the first gain when the absolute value of position deviation is less than the value of (grade - hysteresis) and the duration is greater than [P02-13], the first gain is returned .
708 )))
709 |8|Position command|(((
710 In the previous first gain, if the position command is not 0, switch to the second gain;
711
712 In the previous second gain, if the position command is 0 and the duration is greater than [P02-13], the first gain is returned.
713 )))
714 |(((
715
716
717 9
718 )))|(((
719
720
721 Positioning complete
722 )))|(((
723 In the previous first gain, if the positioning is not completed, the second gain is switched; In the previous second gain, if the positioning is not completed and the duration is greater than [P02-13], the first gain is returned.
724
725
726 )))
727 |(((
728
729
730 10
731 )))|(((
732
733
734 Position command + actual speed
735 )))|(((
736 In the previous first gain, if the position command is not 0, the second gain is switched;
737
738 In the previous second gain, if the position command is 0, the duration is greater than [P02-13] and the absolute value of actual speed is less than ( grade - hysteresis).
739
740
741 )))
742
743
744 )))
745
746 |(% rowspan="2" %)
747 **P02-13**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
748 |Delay Time for Gain Switching|Operation setting|Effective immediately|20|0 to 10000|Gain control|0.1ms
749 |(% colspan="8" %)(((
750 The duration of the switching condition required for the second gain to switch back to the first gain.
751
752 [[image:image-20230515140953-9.png]]
753
754 **✎**Note: This parameter is only valid when the second gain is switched back to the first gain.
755 )))
756
757 |(% rowspan="2" %)
758 **P02-14**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
759 |Gain switching grade|Operation setting|Effective immediately|50|0 to 20000|Gain control|According to the switching conditions
760 |(% colspan="8" %)(((
761 Set the grade of the gain condition. The generation of the actual switching action is affected by the two conditions of grade and hysteresis.
762
763 [[image:image-20230515140953-10.png]]
764 )))
765
766 |(% rowspan="2" %)
767 **P02-15**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
768 |Gain switching hysteresis|Operation setting|Effective immediately|20|0 to 20000|Gain control|According to the switching conditions
769 |(% colspan="8" %)(((
770 Set the hysteresis to meet the gain switching condition.
771
772 [[image:image-20230515140953-11.png]]
773 )))
774
775 |(% rowspan="2" %)
776 **P02-16**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
777 |Position loop gain switching time|Operation setting|Effective immediately|30|0 to 10000|Gain control|0.1ms
778 |(% colspan="8" %)(((
779 Set the time for switching from the first position loop (P02-01) to the second position loop (P02-04) in the position control mode.
780
781 [[image:image-20230515140953-12.png]]
782
783 If P02-04≤P02-01, then P02-16 is invalid, and the second gain is switched from the first gain immediately.
784 )))
785
786 == **Model Tracking Control Function** ==
787
788 Model tracking control is suitable for position control mode, which adds a model loop outside the three loop. In the model loop, new position commands, speed feedforward and torque feedforward and other control quantities are generated according to the user's response requirements to the system and the ideal motor control model. Applying these control quantities to the actual control loop can significantly improve the response performance and positioning performance of the position control, the design block diagram is as follows:
789
790 (% style="text-align:center" %)
791 [[image:20230515-7.png]]
792
793 The usage method and conditions of model tracking control:
794
795 ~1. Correctly set the inertia ratio of the system P3-1, which can be obtained by monitoring the real-time load inertia ratio of U0-20.
796
797 2. Set the load rigidity level P3-2, set an appropriate value, it is not need to set a high rigidity level (recommended value 17~~21 under rigid load).
798
799 3. Set P2-20=1 to enable the function of model tracking control.
800
801 4. Adjust the P2-21 model tracking control gain from small to large, and gradually increase in steps of 1000 until the responsiveness of the system meets the actual demand. The responsiveness of the system is mainly determined by this parameter.
802
803 5. After the responsiveness meets the requirements, user can adjust the parameters appropriately to increase the load rigidity level P3-2.
804
805 **✎Note**: Model tracking control is only available in position mode, and cannot be used in other modes.
806
807 |**Function code**|**Name**|(((
808 **Setting**
809
810 **method**
811 )))|(((
812 **Effective**
813
814 **time**
815 )))|**Default**|**Range**|**Definition**|**Unit**
816 |P2-20|Model tracking control function|Shutdown setting|(((
817 Effective
818
819 immediately
820 )))|0|0 to 1|When the function code is set to 1, enable the model tracking control function.|
821 |P2-21|Model tracking control gain|Shutdown setting|(((
822 Effective
823
824 immediately
825 )))|1000|200 to 20000|(% rowspan="2" %)Increasing the model tracking control gain can improve the position response performance of the model loop. If the gain is too high, it may cause overshoot behavior. The gain compensation affects the damping ratio of the model loop, and the damping ratio becomes larger as the gain compensation becomes larger.|0.1/s
826 |P2-22|Model tracking control gain compensation|Shutdown setting|(((
827 Effective
828
829 immediately
830 )))|1000|500 to 2000|0.10%
831
832 |**Function code**|**Name**|(((
833 **Setting**
834
835 **method**
836 )))|(((
837 **Effective**
838
839 **time**
840 )))|**Default**|**Range**|**Definition**|**Unit**
841 |P2-23|Model tracking control forward rotation bias|(((
842 Operation
843
844 setting
845 )))|(((
846 Effective
847
848 immediately
849 )))|1000|0 to 10000|(% rowspan="2" %)Torque feedforward size in the positive and reverse direction under model tracking control|0.10%
850 |P2-24|Model tracking control reverses rotation bias|(((
851 Operation
852
853 setting
854 )))|(((
855 Effective
856
857 immediately
858 )))|1000|0 to 10000|0.10%
859 |P2-25|Model tracking control speed feedforward compensation|Operation setting|(((
860 Effective
861
862 immediately
863 )))|1000|0 to 10000|The size of the speed feedforward under model tracking control|0.10%
864
865 Please refer to the following for an example of the procedure of adjusting servo gain.
866
867 |**Step**|**Content**
868 |1|Please try to set the correct load inertia ratio parameter P3-1.
869 |2|If the automatic adjustment mode is used (P3-3 is set to 0), please set the basic rigidity level parameter P3-2. If in manual adjustment mode (P3-3 is set to 1), please set the gain P2-1~~P2-3 related to the position loop and speed loop and the torque filter time constant P4-4. The setting principle is mainly no vibration and overshoot.
870 |3|Turn on the model tracking function, set P2-20 to 1.
871 |4|Increase the model tracking gain P2-21 within the range of no overshoot and vibration occur.
872 |5|If the rigidity level of step 2 is set relatively low, user can properly increase the rigidity level P3-2.
873 |6|When overshoot occurs, or the responses of forward rotation and reverse rotation are different, user can fine-tune through model tracking control forward bias P2-23, model tracking control reverse bias P2-24, model tracking control speed feedforward compensation P2 -25.
874
875 == **Gain switching** ==
876
877 Gain switching function:
878
879 ●Switch to a lower gain in the motor stationary (servo enabled)state to suppress vibration;
880
881 ●Switch to a higher gain in the motor stationary state to shorten the positioning time;
882
883 ●Switch to a higher gain in the motor running state to get better command tracking performance;
884
885 ●Switch different gain settings by external signals depending on the load connected.
886
887 (1) Gain switching parameter setting
888
889 ①When P02-07=0
890
891 Fixed use of the first gain (using P02-01~~P02-03), and the switching of P/PI (proportional/proportional integral) control could be realized through DI function 10 (GAIN-SEL, gain switching).
892
893 (% style="text-align:center" %)
894 [[image:20230515-8.png]]
895
896 ② When P02-07=1
897
898 The switching conditions can be set through parameter P02-08 to realize switching between the first gain (P02-01~~P02-03) and the second gain (P02-04~~P02-06).
899
900 (% style="text-align:center" %)
901 [[image:20230515-9.png]]
902
903 Figure 7-9 Flow chart of gain switching when P02-07=1
904
905 |(% style="width:72px" %)**P02-08**|(% style="width:146px" %)**Content**|**Diagram**
906 |(% style="width:72px" %)0|(% style="width:146px" %)Fixed use of the first gain|~-~-
907 |(% style="width:72px" %)1|(% style="width:146px" %)Switching with DI|~-~-
908 |(% style="width:72px" %)(((
909
910
911
912
913
914
915 2
916 )))|(% style="width:146px" %)(((
917
918
919
920
921
922
923 Large torque command
924 )))|[[image:image-20230515140641-1.png]]
925 |(% style="width:72px" %)(((
926
927
928
929
930
931
932
933 3
934 )))|(% style="width:146px" %)Large actual torque|[[image:image-20230515140641-2.png]]
935 |(% style="width:72px" %)(((
936
937
938
939
940
941
942 4
943 )))|(% style="width:146px" %)(((
944
945
946
947
948
949
950 Large speed command
951 )))|[[image:image-20230515140641-3.png]]
952
953 |(% style="width:74px" %)**P02-08**|(% style="width:176px" %)**Content**|**Diagram**
954 |(% style="width:74px" %)(((
955
956
957
958
959
960 5
961 )))|(% style="width:176px" %)(((
962
963
964
965
966
967 Fast actual speed
968 )))|(((
969
970
971 [[image:image-20230515140641-4.png]]
972 )))
973 |(% style="width:74px" %)(((
974
975
976
977
978
979
980
981 6
982 )))|(% style="width:176px" %)(((
983
984
985
986
987
988
989
990 Speed command change rate is large
991 )))|[[image:image-20230515140641-5.png]]
992 |(% style="width:74px" %)(((
993
994
995
996
997
998
999 7
1000
1001
1002 )))|(% style="width:176px" %)(((
1003
1004
1005
1006
1007
1008
1009 Large position deviation
1010 )))|[[image:image-20230515140641-6.png]]
1011 |(% style="width:74px" %)(((
1012
1013
1014
1015
1016
1017 8
1018 )))|(% style="width:176px" %)(((
1019
1020
1021
1022
1023
1024 Position command
1025 )))|[[image:image-20230515140641-7.png]]
1026
1027 |(% style="width:73px" %)(((
1028
1029
1030
1031
1032
1033
1034 9
1035 )))|(% style="width:154px" %)(((
1036
1037
1038
1039
1040
1041
1042 Positioning completed
1043 )))|[[image:image-20230515140641-8.png]]
1044 |(% style="width:73px" %)(((
1045
1046
1047 10
1048
1049
1050 )))|(% style="width:154px" %)(((
1051
1052
1053 Position command + actual speed
1054 )))|(((
1055
1056
1057 Refer to the chart below
1058 )))
1059
1060 (% style="text-align:center" %)
1061 [[image:20230515-10.png]]
1062
1063 Figure 7-10 P02-08=10 Position command + actual speed gain description
1064
1065 (2) Description of related parameters
1066
1067 |(% rowspan="2" style="width:68px" %)
1068 **P02-07**|(% style="width:150px" %)**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1069 |(% style="width:150px" %)The second gain switching mode|Operation setting|Effective immediately|0|0 to 1|Gain control|
1070 |(% colspan="8" %)(((
1071 Set the switching mode of the second gain.
1072
1073 |**Setting value**|**Function**
1074 |0|(((
1075 The first gain is used by default. Switching using DI function 10 (GAIN-SEL, gain switching):
1076
1077 DI logic invalid: PI control;
1078
1079 DI logic valid: PI control.
1080 )))
1081 |1|The first gain and the second gain are switched by the setting value of P02-08.
1082 )))
1083
1084 |(% rowspan="2" %)
1085 **P02-08**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1086 |Gain switching condition selection|Operation setting|Effective immediately|0|0 to 10|Gain control|
1087 |(% colspan="8" %)(((
1088 Set the conditions for gain switching.
1089
1090 |Setting value|Gain switching conditions|Details
1091 |0|The default is the first gain|Fixed use of the first gain
1092 |1|Switch by DI port|(((
1093 Use DI function 10 (GAIN-SEL, gain switching);
1094
1095 DI logic is invalid: the first gain (P02-01~~P02-03);
1096
1097 DI logic is valid: the second gain (P02-04~~P02-06).
1098 )))
1099 |2|Large torque command|(((
1100 In the previous first gain, when the absolute value of torque command is greater than (grade + hysteresis), the second gain is switched;
1101
1102 In the previous second gain, when the absolute value of torque command is less than the value of (grade - hysteresis) and the duration is greater than [P02-13], the first gain is returned.
1103
1104
1105 )))
1106 |3|Large actual torque|(((
1107 In the previous first gain, when the absolute value of actual torque is greater than ( grade + hysteresis ), the second gain is switched;
1108
1109 In the previous second gain, when the absolute value of actual torque is less than the value of (grade - hysteresis) and the duration is greater than [P02-13], the first gain is returned .
1110
1111
1112 )))
1113 |4|Large speed command|(((
1114 In the previous first gain, when the absolute value of speed command is greater than (grade + hysteresis), the second gain is switched;
1115
1116 In the previous second gain, when the absolute value of speed command is less than the value of (grade - hysteresis) and the duration is greater than [P02-13], the first gain is returned .
1117
1118
1119 )))
1120 |5|Large actual speed|(((
1121 In the previous first gain, when the absolute value of actual speed is greater than (grade + hysteresis), the second gain is switched;
1122
1123 In the previous second gain, when the absolute value of actual speed is less than the value of (grade - hysteresis) and the duration is greater than [P02-13], the first gain is returned .
1124
1125
1126 )))
1127 |(((
1128
1129
1130 6
1131 )))|(((
1132
1133
1134 Large rate of change in speed command
1135 )))|(((
1136 In the previous first gain, when the absolute value of the rate of change in speed command is greater than (grade + hysteresis), the second gain is switched;
1137
1138 In the previous second gain, switch to the first gain when the absolute value of the rate of change in speed command is less than the value of (grade - hysteresis) and the duration is greater than [P02-13], the first gain is returned .
1139
1140
1141 )))
1142 |(((
1143
1144
1145 7
1146 )))|(((
1147
1148
1149 Large position deviation
1150 )))|(((
1151 In the previous first gain, when the absolute value of position deviation is greater than (grade + hysteresis), the second gain is switched;
1152
1153 In the previous second gain, switch to the first gain when the absolute value of position deviation is less than the value of (grade - hysteresis) and the duration is greater than [P02-13], the first gain is returned .
1154 )))
1155 |8|Position command|(((
1156 In the previous first gain, if the position command is not 0, switch to the second gain;
1157
1158 In the previous second gain, if the position command is 0 and the duration is greater than [P02-13], the first gain is returned.
1159 )))
1160 |(((
1161
1162
1163 9
1164 )))|(((
1165
1166
1167 Positioning complete
1168 )))|(((
1169 In the previous first gain, if the positioning is not completed, the second gain is switched; In the previous second gain, if the positioning is not completed and the duration is greater than [P02-13], the first gain is returned.
1170
1171
1172 )))
1173 |(((
1174
1175
1176 10
1177 )))|(((
1178
1179
1180 Position command + actual speed
1181 )))|(((
1182 In the previous first gain, if the position command is not 0, the second gain is switched;
1183
1184 In the previous second gain, if the position command is 0, the duration is greater than [P02-13] and the absolute value of actual speed is less than ( grade - hysteresis).
1185
1186
1187 )))
1188
1189
1190 )))
1191
1192 |(% rowspan="2" %)
1193 **P02-13**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1194 |Delay Time for Gain Switching|Operation setting|Effective immediately|20|0 to 10000|Gain control|0.1ms
1195 |(% colspan="8" %)(((
1196 The duration of the switching condition required for the second gain to switch back to the first gain.
1197
1198 [[image:image-20230515140953-9.png]]
1199
1200 **✎**Note: This parameter is only valid when the second gain is switched back to the first gain.
1201 )))
1202
1203 |(% rowspan="2" %)
1204 **P02-14**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1205 |Gain switching grade|Operation setting|Effective immediately|50|0 to 20000|Gain control|According to the switching conditions
1206 |(% colspan="8" %)(((
1207 Set the grade of the gain condition. The generation of the actual switching action is affected by the two conditions of grade and hysteresis.
1208
1209 [[image:image-20230515140953-10.png]]
1210 )))
1211
1212 |(% rowspan="2" %)
1213 **P02-15**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1214 |Gain switching hysteresis|Operation setting|Effective immediately|20|0 to 20000|Gain control|According to the switching conditions
1215 |(% colspan="8" %)(((
1216 Set the hysteresis to meet the gain switching condition.
1217
1218 [[image:image-20230515140953-11.png]]
1219 )))
1220
1221 |(% rowspan="2" %)
1222 **P02-16**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1223 |Position loop gain switching time|Operation setting|Effective immediately|30|0 to 10000|Gain control|0.1ms
1224 |(% colspan="8" %)(((
1225 Set the time for switching from the first position loop (P02-01) to the second position loop (P02-04) in the position control mode.
1226
1227 [[image:image-20230515140953-12.png]]
1228
1229 If P02-04≤P02-01, then P02-16 is invalid, and the second gain is switched from the first gain immediately.
1230 )))
1231
1232 = **Mechanical resonance suppression** =
1233
1234 == Mechanical resonance suppression methods ==
1235
1236 When the mechanical rigidity is low, vibration and noise may occur due to resonance caused by shaft twisting, and it may not be possible to increase the gain setting. In this case, by using a notch filter to reduce the gain at a specific frequency, after resonance is effectively suppressed, you can continue to increase the servo gain. There are 2 methods to suppress mechanical resonance.
1237
1238 **Torque instruction filter**
1239
1240 By setting the filter time constant, the torque instruction is attenuated in the high frequency range above the cutoff frequency, so as to achieve the expectation of suppressing mechanical resonance. The cut-off frequency of the torque instruction filter could be calculated by the following formula:
1241
1242 (% style="text-align:center" %)
1243 [[image:image-20220706155820-5.jpeg||class="img-thumbnail"]]
1244
1245 **Notch filter**
1246
1247 The notch filter can achieve the expectation of suppressing mechanical resonance by reducing the gain at a specific frequency. When setting the notch filter correctly, the vibration can be effectively suppressed. You can try to increase the servo gain. The principle of the notch filter is shown in __Figure 7-3__.
1248
1249 == Notch filter ==
1250
1251 The VD2 series servo drives have 2 sets of notch filters, each of which has 3 parameters, namely notch frequency, width grade and depth grade.
1252
1253 **Width grade of notch filter**
1254
1255 The notch width grade is used to express the ratio of the notch width to the center frequency of the notch:
1256
1257 (% style="text-align:center" %)
1258 [[image:image-20220706155836-6.png||class="img-thumbnail"]]
1259
1260 In formula (7-1), [[image:image-20220706155946-7.png]] is the center frequency of notch filter, that is, the mechanical resonance frequency; [[image:image-20220706155952-8.png]] is the width of notch filter, which represents the frequency bandwidth with an amplitude attenuation rate of **-3dB** relative to the center frequency of notch filter.
1261
1262 **Depth grade of notch filter**
1263
1264 The depth grade of notch filter represents the ratio relationship between input and output at center frequency.
1265
1266 When the notch filter depth grade is 0, the input is completely suppressed at center frequency. When the notch filter depth grade is 100, the input is completely passable at center frequency. Therefore, the smaller the the notch filter depth grade is set, the deeper the the notch filter depth, and the stronger the suppression of mechanical resonance. But the system may be unstable, you should pay attention to it when using it. The specific relationship is shown in __Figure 7-4__.
1267
1268 (% style="text-align:center" %)
1269 (((
1270 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
1271 [[Figure 7-7 Notch characteristics, notch width, and notch depth>>image:image-20220608174259-3.png||id="Iimage-20220608174259-3.png"]]
1272 )))
1273
1274
1275 (% style="text-align:center" %)
1276 (((
1277 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
1278 [[Figure 7-8 Frequency characteristics of notch filter>>image:image-20220706160046-9.png||id="Iimage-20220706160046-9.png"]]
1279 )))
1280
1281
1282 (% class="table-bordered" %)
1283 |=(% scope="row" style="text-align: center; vertical-align: middle; width: 113px;" %)**Function code**|=(% style="text-align: center; vertical-align: middle; width: 155px;" %)**Name**|=(% style="text-align: center; vertical-align: middle; width: 115px;" %)(((
1284 **Setting method**
1285 )))|=(% style="text-align: center; vertical-align: middle; width: 121px;" %)(((
1286 **Effective time**
1287 )))|=(% style="text-align: center; vertical-align: middle; width: 99px;" %)**Default value**|=(% style="text-align: center; vertical-align: middle; width: 102px;" %)**Range**|=(% style="text-align: center; vertical-align: middle; width: 362px;" %)**Definition**|=(% style="text-align: center; vertical-align: middle; width: 96px;" %)**Unit**
1288 |=(% style="text-align: center; vertical-align: middle; width: 113px;" %)P04-05|(% style="text-align:center; vertical-align:middle; width:155px" %)1st notch filter frequency|(% style="text-align:center; vertical-align:middle; width:115px" %)(((
1289 Operation setting
1290 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1291 Effective immediately
1292 )))|(% style="text-align:center; vertical-align:middle; width:99px" %)300|(% style="text-align:center; vertical-align:middle; width:102px" %)250 to 5000|(% style="width:362px" %)Set the center frequency of the 1st notch filter. When the set value is 5000, the function of notch filter is invalid.|(% style="text-align:center; vertical-align:middle; width:96px" %)Hz
1293 |=(% style="text-align: center; vertical-align: middle; width: 113px;" %)P04-06|(% style="text-align:center; vertical-align:middle; width:155px" %)1st notch filter depth|(% style="text-align:center; vertical-align:middle; width:115px" %)(((
1294 Operation setting
1295 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1296 Effective immediately
1297 )))|(% style="text-align:center; vertical-align:middle; width:99px" %)100|(% style="text-align:center; vertical-align:middle; width:102px" %)0 to 100|(% style="width:362px" %)(((
1298 1. 0: all truncated
1299 1. 100: all passed
1300 )))|(% style="text-align:center; vertical-align:middle; width:96px" %)-
1301 |=(% style="text-align: center; vertical-align: middle; width: 113px;" %)P04-07|(% style="text-align:center; vertical-align:middle; width:155px" %)1st notch filter width|(% style="text-align:center; vertical-align:middle; width:115px" %)(((
1302 Operation setting
1303 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1304 Effective immediately
1305 )))|(% style="text-align:center; vertical-align:middle; width:99px" %)4|(% style="text-align:center; vertical-align:middle; width:102px" %)0 to 12|(% style="width:362px" %)(((
1306 1. 0: 0.5 times the bandwidth
1307 1. 4: 1 times the bandwidth
1308 1. 8: 2 times the bandwidth
1309 1. 12: 4 times the bandwidth
1310 )))|(% style="text-align:center; vertical-align:middle; width:96px" %)-
1311 |=(% style="text-align: center; vertical-align: middle; width: 113px;" %)P04-08|(% style="text-align:center; vertical-align:middle; width:155px" %)2nd notch filter frequency|(% style="text-align:center; vertical-align:middle; width:115px" %)(((
1312 Operation setting
1313 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1314 Effective immediately
1315 )))|(% style="text-align:center; vertical-align:middle; width:99px" %)500|(% style="text-align:center; vertical-align:middle; width:102px" %)250 to 5000|(% style="width:362px" %)Set the center frequency of the 2nd notch filter. When the set value is 5000, the function of the notch filter is invalid.|(% style="text-align:center; vertical-align:middle; width:96px" %)Hz
1316 |=(% style="text-align: center; vertical-align: middle; width: 113px;" %)P04-09|(% style="text-align:center; vertical-align:middle; width:155px" %)2nd notch filter depth|(% style="text-align:center; vertical-align:middle; width:115px" %)(((
1317 Operation setting
1318 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1319 Effective immediately
1320 )))|(% style="text-align:center; vertical-align:middle; width:99px" %)100|(% style="text-align:center; vertical-align:middle; width:102px" %)0 to 100|(% style="width:362px" %)(((
1321 1. 0: all truncated
1322 1. 100: all passed
1323 )))|(% style="text-align:center; vertical-align:middle; width:96px" %)-
1324 |=(% style="text-align: center; vertical-align: middle; width: 113px;" %)P04-10|(% style="text-align:center; vertical-align:middle; width:155px" %)2nd notch filter width|(% style="text-align:center; vertical-align:middle; width:115px" %)(((
1325 Operation setting
1326 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1327 Effective immediately
1328 )))|(% style="text-align:center; vertical-align:middle; width:99px" %)4|(% style="text-align:center; vertical-align:middle; width:102px" %)0 to 12|(% style="width:362px" %)(((
1329 1. 0: 0.5 times the bandwidth
1330 1. 4: 1 times the bandwidth
1331 1. 8: 2 times the bandwidth
1332 1. 12: 4 times the bandwidth
1333 )))|(% style="text-align:center; vertical-align:middle; width:96px" %)-
1334
1335 Table 7-11 Notch filter function code parameters
1336 ~)~)~)