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Wiki source code of 07 Adjustments

Version 26.1 by Karen on 2023/05/15 15:29
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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 (1) 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 [[image:20230515-8.png]]
445
446 ② When P02-07=1
447
448 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).
449
450 (% style="text-align:center" %)
451 [[image:20230515-9.png]]
452
453 Figure 7-9 Flow chart of gain switching when P02-07=1
454
455 |(% style="width:72px" %)**P02-08**|(% style="width:146px" %)**Content**|**Diagram**
456 |(% style="width:72px" %)0|(% style="width:146px" %)Fixed use of the first gain|~-~-
457 |(% style="width:72px" %)1|(% style="width:146px" %)Switching with DI|~-~-
458 |(% style="width:72px" %)(((
459
460
461
462
463
464
465 2
466 )))|(% style="width:146px" %)(((
467
468
469
470
471
472
473 Large torque command
474 )))|[[image:image-20230515140641-1.png]]
475 |(% style="width:72px" %)(((
476
477
478
479
480
481
482
483 3
484 )))|(% style="width:146px" %)Large actual torque|[[image:image-20230515140641-2.png]]
485 |(% style="width:72px" %)(((
486
487
488
489
490
491
492 4
493 )))|(% style="width:146px" %)(((
494
495
496
497
498
499
500 Large speed command
501 )))|[[image:image-20230515140641-3.png]]
502
503 |(% style="width:74px" %)**P02-08**|(% style="width:176px" %)**Content**|**Diagram**
504 |(% style="width:74px" %)(((
505
506
507
508
509
510 5
511 )))|(% style="width:176px" %)(((
512
513
514
515
516
517 Fast actual speed
518 )))|(((
519
520
521 [[image:image-20230515140641-4.png]]
522 )))
523 |(% style="width:74px" %)(((
524
525
526
527
528
529
530
531 6
532 )))|(% style="width:176px" %)(((
533
534
535
536
537
538
539
540 Speed command change rate is large
541 )))|[[image:image-20230515140641-5.png]]
542 |(% style="width:74px" %)(((
543
544
545
546
547
548
549 7
550
551
552 )))|(% style="width:176px" %)(((
553
554
555
556
557
558
559 Large position deviation
560 )))|[[image:image-20230515140641-6.png]]
561 |(% style="width:74px" %)(((
562
563
564
565
566
567 8
568 )))|(% style="width:176px" %)(((
569
570
571
572
573
574 Position command
575 )))|[[image:image-20230515140641-7.png]]
576
577 |(% style="width:73px" %)(((
578
579
580
581
582
583
584 9
585 )))|(% style="width:154px" %)(((
586
587
588
589
590
591
592 Positioning completed
593 )))|[[image:image-20230515140641-8.png]]
594 |(% style="width:73px" %)(((
595
596
597 10
598
599
600 )))|(% style="width:154px" %)(((
601
602
603 Position command + actual speed
604 )))|(((
605
606
607 Refer to the chart below
608 )))
609
610 (% style="text-align:center" %)
611 [[image:20230515-10.png]]
612
613 Figure 7-10 P02-08=10 Position command + actual speed gain description
614
615 (2) Description of related parameters
616
617 |(% rowspan="2" style="width:68px" %)
618 **P02-07**|(% style="width:150px" %)**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
619 |(% style="width:150px" %)The second gain switching mode|Operation setting|Effective immediately|0|0 to 1|Gain control|
620 |(% colspan="8" %)(((
621 Set the switching mode of the second gain.
622
623 |**Setting value**|**Function**
624 |0|(((
625 The first gain is used by default. Switching using DI function 10 (GAIN-SEL, gain switching):
626
627 DI logic invalid: PI control;
628
629 DI logic valid: PI control.
630 )))
631 |1|The first gain and the second gain are switched by the setting value of P02-08.
632 )))
633
634 |(% rowspan="2" %)
635 **P02-08**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
636 |Gain switching condition selection|Operation setting|Effective immediately|0|0 to 10|Gain control|
637 |(% colspan="8" %)(((
638 Set the conditions for gain switching.
639
640 |Setting value|Gain switching conditions|Details
641 |0|The default is the first gain|Fixed use of the first gain
642 |1|Switch by DI port|(((
643 Use DI function 10 (GAIN-SEL, gain switching);
644
645 DI logic is invalid: the first gain (P02-01~~P02-03);
646
647 DI logic is valid: the second gain (P02-04~~P02-06).
648 )))
649 |2|Large torque command|(((
650 In the previous first gain, when the absolute value of torque command is greater than (grade + hysteresis), the second gain is switched;
651
652 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.
653
654
655 )))
656 |3|Large actual torque|(((
657 In the previous first gain, when the absolute value of actual torque is greater than ( grade + hysteresis ), the second gain is switched;
658
659 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 .
660
661
662 )))
663 |4|Large speed command|(((
664 In the previous first gain, when the absolute value of speed command is greater than (grade + hysteresis), the second gain is switched;
665
666 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 .
667
668
669 )))
670 |5|Large actual speed|(((
671 In the previous first gain, when the absolute value of actual speed is greater than (grade + hysteresis), the second gain is switched;
672
673 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 .
674
675
676 )))
677 |(((
678
679
680 6
681 )))|(((
682
683
684 Large rate of change in speed command
685 )))|(((
686 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;
687
688 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 .
689
690
691 )))
692 |(((
693
694
695 7
696 )))|(((
697
698
699 Large position deviation
700 )))|(((
701 In the previous first gain, when the absolute value of position deviation is greater than (grade + hysteresis), the second gain is switched;
702
703 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 .
704 )))
705 |8|Position command|(((
706 In the previous first gain, if the position command is not 0, switch to the second gain;
707
708 In the previous second gain, if the position command is 0 and the duration is greater than [P02-13], the first gain is returned.
709 )))
710 |(((
711
712
713 9
714 )))|(((
715
716
717 Positioning complete
718 )))|(((
719 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.
720
721
722 )))
723 |(((
724
725
726 10
727 )))|(((
728
729
730 Position command + actual speed
731 )))|(((
732 In the previous first gain, if the position command is not 0, the second gain is switched;
733
734 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).
735
736
737 )))
738
739
740 )))
741
742 |(% rowspan="2" %)
743 **P02-13**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
744 |Delay Time for Gain Switching|Operation setting|Effective immediately|20|0 to 10000|Gain control|0.1ms
745 |(% colspan="8" %)(((
746 The duration of the switching condition required for the second gain to switch back to the first gain.
747
748 [[image:image-20230515140953-9.png]]
749
750 **✎**Note: This parameter is only valid when the second gain is switched back to the first gain.
751 )))
752
753 |(% rowspan="2" %)
754 **P02-14**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
755 |Gain switching grade|Operation setting|Effective immediately|50|0 to 20000|Gain control|According to the switching conditions
756 |(% colspan="8" %)(((
757 Set the grade of the gain condition. The generation of the actual switching action is affected by the two conditions of grade and hysteresis.
758
759 [[image:image-20230515140953-10.png]]
760 )))
761
762 |(% rowspan="2" %)
763 **P02-15**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
764 |Gain switching hysteresis|Operation setting|Effective immediately|20|0 to 20000|Gain control|According to the switching conditions
765 |(% colspan="8" %)(((
766 Set the hysteresis to meet the gain switching condition.
767
768 [[image:image-20230515140953-11.png]]
769 )))
770
771 |(% rowspan="2" %)
772 **P02-16**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
773 |Position loop gain switching time|Operation setting|Effective immediately|30|0 to 10000|Gain control|0.1ms
774 |(% colspan="8" %)(((
775 Set the time for switching from the first position loop (P02-01) to the second position loop (P02-04) in the position control mode.
776
777 [[image:image-20230515140953-12.png]]
778
779 If P02-04≤P02-01, then P02-16 is invalid, and the second gain is switched from the first gain immediately.
780 )))
781
782 == **Model Tracking Control Function** ==
783
784 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:
785
786 (% style="text-align:center" %)
787 [[image:20230515-7.png]]
788
789 The usage method and conditions of model tracking control:
790
791 ~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.
792
793 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).
794
795 3. Set P2-20=1 to enable the function of model tracking control.
796
797 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.
798
799 5. After the responsiveness meets the requirements, user can adjust the parameters appropriately to increase the load rigidity level P3-2.
800
801 **✎Note**: Model tracking control is only available in position mode, and cannot be used in other modes.
802
803 |**Function code**|**Name**|(((
804 **Setting**
805
806 **method**
807 )))|(((
808 **Effective**
809
810 **time**
811 )))|**Default**|**Range**|**Definition**|**Unit**
812 |P2-20|Model tracking control function|Shutdown setting|(((
813 Effective
814
815 immediately
816 )))|0|0 to 1|When the function code is set to 1, enable the model tracking control function.|
817 |P2-21|Model tracking control gain|Shutdown setting|(((
818 Effective
819
820 immediately
821 )))|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
822 |P2-22|Model tracking control gain compensation|Shutdown setting|(((
823 Effective
824
825 immediately
826 )))|1000|500 to 2000|0.10%
827
828 |**Function code**|**Name**|(((
829 **Setting**
830
831 **method**
832 )))|(((
833 **Effective**
834
835 **time**
836 )))|**Default**|**Range**|**Definition**|**Unit**
837 |P2-23|Model tracking control forward rotation bias|(((
838 Operation
839
840 setting
841 )))|(((
842 Effective
843
844 immediately
845 )))|1000|0 to 10000|(% rowspan="2" %)Torque feedforward size in the positive and reverse direction under model tracking control|0.10%
846 |P2-24|Model tracking control reverses rotation bias|(((
847 Operation
848
849 setting
850 )))|(((
851 Effective
852
853 immediately
854 )))|1000|0 to 10000|0.10%
855 |P2-25|Model tracking control speed feedforward compensation|Operation setting|(((
856 Effective
857
858 immediately
859 )))|1000|0 to 10000|The size of the speed feedforward under model tracking control|0.10%
860
861 Please refer to the following for an example of the procedure of adjusting servo gain.
862
863 |**Step**|**Content**
864 |1|Please try to set the correct load inertia ratio parameter P3-1.
865 |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.
866 |3|Turn on the model tracking function, set P2-20 to 1.
867 |4|Increase the model tracking gain P2-21 within the range of no overshoot and vibration occur.
868 |5|If the rigidity level of step 2 is set relatively low, user can properly increase the rigidity level P3-2.
869 |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.
870
871 == **Gain switching** ==
872
873 Gain switching function:
874
875 ●Switch to a lower gain in the motor stationary (servo enabled)state to suppress vibration;
876
877 ●Switch to a higher gain in the motor stationary state to shorten the positioning time;
878
879 ●Switch to a higher gain in the motor running state to get better command tracking performance;
880
881 ●Switch different gain settings by external signals depending on the load connected.
882
883 (1) Gain switching parameter setting
884
885 ①When P02-07=0
886
887 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).
888
889 (% style="text-align:center" %)
890 [[image:20230515-8.png]]
891
892 ② When P02-07=1
893
894 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).
895
896 (% style="text-align:center" %)
897 [[image:20230515-9.png]]
898
899 Figure 7-9 Flow chart of gain switching when P02-07=1
900
901 |(% style="width:72px" %)**P02-08**|(% style="width:146px" %)**Content**|**Diagram**
902 |(% style="width:72px" %)0|(% style="width:146px" %)Fixed use of the first gain|~-~-
903 |(% style="width:72px" %)1|(% style="width:146px" %)Switching with DI|~-~-
904 |(% style="width:72px" %)(((
905
906
907
908
909
910
911 2
912 )))|(% style="width:146px" %)(((
913
914
915
916
917
918
919 Large torque command
920 )))|[[image:image-20230515140641-1.png]]
921 |(% style="width:72px" %)(((
922
923
924
925
926
927
928
929 3
930 )))|(% style="width:146px" %)Large actual torque|[[image:image-20230515140641-2.png]]
931 |(% style="width:72px" %)(((
932
933
934
935
936
937
938 4
939 )))|(% style="width:146px" %)(((
940
941
942
943
944
945
946 Large speed command
947 )))|[[image:image-20230515140641-3.png]]
948
949 |(% style="width:74px" %)**P02-08**|(% style="width:176px" %)**Content**|**Diagram**
950 |(% style="width:74px" %)(((
951
952
953
954
955
956 5
957 )))|(% style="width:176px" %)(((
958
959
960
961
962
963 Fast actual speed
964 )))|(((
965
966
967 [[image:image-20230515140641-4.png]]
968 )))
969 |(% style="width:74px" %)(((
970
971
972
973
974
975
976
977 6
978 )))|(% style="width:176px" %)(((
979
980
981
982
983
984
985
986 Speed command change rate is large
987 )))|[[image:image-20230515140641-5.png]]
988 |(% style="width:74px" %)(((
989
990
991
992
993
994
995 7
996
997
998 )))|(% style="width:176px" %)(((
999
1000
1001
1002
1003
1004
1005 Large position deviation
1006 )))|[[image:image-20230515140641-6.png]]
1007 |(% style="width:74px" %)(((
1008
1009
1010
1011
1012
1013 8
1014 )))|(% style="width:176px" %)(((
1015
1016
1017
1018
1019
1020 Position command
1021 )))|[[image:image-20230515140641-7.png]]
1022
1023 |(% style="width:73px" %)(((
1024
1025
1026
1027
1028
1029
1030 9
1031 )))|(% style="width:154px" %)(((
1032
1033
1034
1035
1036
1037
1038 Positioning completed
1039 )))|[[image:image-20230515140641-8.png]]
1040 |(% style="width:73px" %)(((
1041
1042
1043 10
1044
1045
1046 )))|(% style="width:154px" %)(((
1047
1048
1049 Position command + actual speed
1050 )))|(((
1051
1052
1053 Refer to the chart below
1054 )))
1055
1056 (% style="text-align:center" %)
1057 [[image:20230515-10.png]]
1058
1059 Figure 7-10 P02-08=10 Position command + actual speed gain description
1060
1061 (2) Description of related parameters
1062
1063 |(% rowspan="2" style="width:68px" %)
1064 **P02-07**|(% style="width:150px" %)**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1065 |(% style="width:150px" %)The second gain switching mode|Operation setting|Effective immediately|0|0 to 1|Gain control|
1066 |(% colspan="8" %)(((
1067 Set the switching mode of the second gain.
1068
1069 |**Setting value**|**Function**
1070 |0|(((
1071 The first gain is used by default. Switching using DI function 10 (GAIN-SEL, gain switching):
1072
1073 DI logic invalid: PI control;
1074
1075 DI logic valid: PI control.
1076 )))
1077 |1|The first gain and the second gain are switched by the setting value of P02-08.
1078 )))
1079
1080 |(% rowspan="2" %)
1081 **P02-08**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1082 |Gain switching condition selection|Operation setting|Effective immediately|0|0 to 10|Gain control|
1083 |(% colspan="8" %)(((
1084 Set the conditions for gain switching.
1085
1086 |Setting value|Gain switching conditions|Details
1087 |0|The default is the first gain|Fixed use of the first gain
1088 |1|Switch by DI port|(((
1089 Use DI function 10 (GAIN-SEL, gain switching);
1090
1091 DI logic is invalid: the first gain (P02-01~~P02-03);
1092
1093 DI logic is valid: the second gain (P02-04~~P02-06).
1094 )))
1095 |2|Large torque command|(((
1096 In the previous first gain, when the absolute value of torque command is greater than (grade + hysteresis), the second gain is switched;
1097
1098 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.
1099
1100
1101 )))
1102 |3|Large actual torque|(((
1103 In the previous first gain, when the absolute value of actual torque is greater than ( grade + hysteresis ), the second gain is switched;
1104
1105 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 .
1106
1107
1108 )))
1109 |4|Large speed command|(((
1110 In the previous first gain, when the absolute value of speed command is greater than (grade + hysteresis), the second gain is switched;
1111
1112 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 .
1113
1114
1115 )))
1116 |5|Large actual speed|(((
1117 In the previous first gain, when the absolute value of actual speed is greater than (grade + hysteresis), the second gain is switched;
1118
1119 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 .
1120
1121
1122 )))
1123 |(((
1124
1125
1126 6
1127 )))|(((
1128
1129
1130 Large rate of change in speed command
1131 )))|(((
1132 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;
1133
1134 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 .
1135
1136
1137 )))
1138 |(((
1139
1140
1141 7
1142 )))|(((
1143
1144
1145 Large position deviation
1146 )))|(((
1147 In the previous first gain, when the absolute value of position deviation is greater than (grade + hysteresis), the second gain is switched;
1148
1149 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 .
1150 )))
1151 |8|Position command|(((
1152 In the previous first gain, if the position command is not 0, switch to the second gain;
1153
1154 In the previous second gain, if the position command is 0 and the duration is greater than [P02-13], the first gain is returned.
1155 )))
1156 |(((
1157
1158
1159 9
1160 )))|(((
1161
1162
1163 Positioning complete
1164 )))|(((
1165 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.
1166
1167
1168 )))
1169 |(((
1170
1171
1172 10
1173 )))|(((
1174
1175
1176 Position command + actual speed
1177 )))|(((
1178 In the previous first gain, if the position command is not 0, the second gain is switched;
1179
1180 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).
1181
1182
1183 )))
1184
1185
1186 )))
1187
1188 |(% rowspan="2" %)
1189 **P02-13**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1190 |Delay Time for Gain Switching|Operation setting|Effective immediately|20|0 to 10000|Gain control|0.1ms
1191 |(% colspan="8" %)(((
1192 The duration of the switching condition required for the second gain to switch back to the first gain.
1193
1194 [[image:image-20230515140953-9.png]]
1195
1196 **✎**Note: This parameter is only valid when the second gain is switched back to the first gain.
1197 )))
1198
1199 |(% rowspan="2" %)
1200 **P02-14**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1201 |Gain switching grade|Operation setting|Effective immediately|50|0 to 20000|Gain control|According to the switching conditions
1202 |(% colspan="8" %)(((
1203 Set the grade of the gain condition. The generation of the actual switching action is affected by the two conditions of grade and hysteresis.
1204
1205 [[image:image-20230515140953-10.png]]
1206 )))
1207
1208 |(% rowspan="2" %)
1209 **P02-15**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1210 |Gain switching hysteresis|Operation setting|Effective immediately|20|0 to 20000|Gain control|According to the switching conditions
1211 |(% colspan="8" %)(((
1212 Set the hysteresis to meet the gain switching condition.
1213
1214 [[image:image-20230515140953-11.png]]
1215 )))
1216
1217 |(% rowspan="2" %)
1218 **P02-16**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1219 |Position loop gain switching time|Operation setting|Effective immediately|30|0 to 10000|Gain control|0.1ms
1220 |(% colspan="8" %)(((
1221 Set the time for switching from the first position loop (P02-01) to the second position loop (P02-04) in the position control mode.
1222
1223 [[image:image-20230515140953-12.png]]
1224
1225 If P02-04≤P02-01, then P02-16 is invalid, and the second gain is switched from the first gain immediately.
1226 )))
1227
1228 = **Mechanical resonance suppression** =
1229
1230 == Mechanical resonance suppression methods ==
1231
1232 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.
1233
1234 **Torque instruction filter**
1235
1236 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:
1237
1238 (% style="text-align:center" %)
1239 [[image:image-20220706155820-5.jpeg||class="img-thumbnail"]]
1240
1241 **Notch filter**
1242
1243 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__.
1244
1245 == Notch filter ==
1246
1247 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.
1248
1249 **Width grade of notch filter**
1250
1251 The notch width grade is used to express the ratio of the notch width to the center frequency of the notch:
1252
1253 (% style="text-align:center" %)
1254 [[image:image-20220706155836-6.png||class="img-thumbnail"]]
1255
1256 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.
1257
1258 **Depth grade of notch filter**
1259
1260 The depth grade of notch filter represents the ratio relationship between input and output at center frequency.
1261
1262 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__.
1263
1264 (% style="text-align:center" %)
1265 (((
1266 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
1267 [[Figure 7-7 Notch characteristics, notch width, and notch depth>>image:image-20220608174259-3.png||id="Iimage-20220608174259-3.png"]]
1268 )))
1269
1270
1271 (% style="text-align:center" %)
1272 (((
1273 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
1274 [[Figure 7-8 Frequency characteristics of notch filter>>image:image-20220706160046-9.png||id="Iimage-20220706160046-9.png"]]
1275 )))
1276
1277
1278 (% class="table-bordered" %)
1279 |=(% 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;" %)(((
1280 **Setting method**
1281 )))|=(% style="text-align: center; vertical-align: middle; width: 121px;" %)(((
1282 **Effective time**
1283 )))|=(% 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**
1284 |=(% 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" %)(((
1285 Operation setting
1286 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1287 Effective immediately
1288 )))|(% 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
1289 |=(% 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" %)(((
1290 Operation setting
1291 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1292 Effective immediately
1293 )))|(% 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" %)(((
1294 1. 0: all truncated
1295 1. 100: all passed
1296 )))|(% style="text-align:center; vertical-align:middle; width:96px" %)-
1297 |=(% 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" %)(((
1298 Operation setting
1299 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1300 Effective immediately
1301 )))|(% 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" %)(((
1302 1. 0: 0.5 times the bandwidth
1303 1. 4: 1 times the bandwidth
1304 1. 8: 2 times the bandwidth
1305 1. 12: 4 times the bandwidth
1306 )))|(% style="text-align:center; vertical-align:middle; width:96px" %)-
1307 |=(% 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" %)(((
1308 Operation setting
1309 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1310 Effective immediately
1311 )))|(% 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
1312 |=(% 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" %)(((
1313 Operation setting
1314 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1315 Effective immediately
1316 )))|(% 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" %)(((
1317 1. 0: all truncated
1318 1. 100: all passed
1319 )))|(% style="text-align:center; vertical-align:middle; width:96px" %)-
1320 |=(% 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" %)(((
1321 Operation setting
1322 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1323 Effective immediately
1324 )))|(% 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" %)(((
1325 1. 0: 0.5 times the bandwidth
1326 1. 4: 1 times the bandwidth
1327 1. 8: 2 times the bandwidth
1328 1. 12: 4 times the bandwidth
1329 )))|(% style="text-align:center; vertical-align:middle; width:96px" %)-
1330
1331 Table 7-11 Notch filter function code parameters
1332 ~)~)~)