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Wiki source code of 07 Adjustments

Version 24.7 by Karen on 2023/05/15 15:24
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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||id="20230515-7.png"]]
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
389 |=(% 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" %)(((
390 Shutdown setting
391 )))|(% style="text-align:center; vertical-align:middle; width:128px" %)(((
392 Effective immediately
393 )))|1000|(% style="text-align:center; vertical-align:middle; width:107px" %)500 to 2000|(% style="text-align:center; vertical-align:middle" %)0.10%
394
395 (% class="table-bordered" %)
396 |=(% 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;" %)(((
397 **Setting method**
398 )))|=(% style="text-align: center; vertical-align: middle; width: 128px;" %)(((
399 **Effective time**
400 )))|=(% 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**
401 |=(% 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|(((
402 Operation setting
403 )))|(% style="text-align:center; vertical-align:middle; width:128px" %)(((
404 Effective immediately
405 )))|(% 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%
406 |=(% 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|(((
407 Operation setting
408 )))|(% style="text-align:center; vertical-align:middle; width:128px" %)(((
409 Effective immediately
410 )))|1000|(% style="text-align:center; vertical-align:middle; width:107px" %)0 to 10000|(% style="text-align:center; vertical-align:middle" %)0.10%
411 |=(% 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" %)(((
412 Effective immediately
413 )))|(% 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%
414
415 Please refer to the following for an example of the procedure of adjusting servo gain.
416
417 (% style="width:1508px" %)
418 |=(% style="text-align:center; vertical-align:middle; width:80px" %)**Step**|(% style="text-align:center; vertical-align:middle; width:1420px" %)**Content**
419 |=(% style="text-align: center; vertical-align: middle; width: 80px;" %)1|Please try to set the correct load inertia ratio parameter P3-1.
420 |=(% 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.
421 |=(% style="text-align: center; vertical-align: middle; width: 80px;" %)3|Turn on the model tracking function, set P2-20 to 1.
422 |=(% 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.
423 |=(% 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.
424 |=(% 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.
425
426 == **Gain switching** ==
427
428 Gain switching function:
429
430 ●Switch to a lower gain in the motor stationary (servo enabled)state to suppress vibration;
431
432 ●Switch to a higher gain in the motor stationary state to shorten the positioning time;
433
434 ●Switch to a higher gain in the motor running state to get better command tracking performance;
435
436 ●Switch different gain settings by external signals depending on the load connected.
437
438 (1) Gain switching parameter setting
439
440 ①When P02-07=0
441
442 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).
443
444 (% style="text-align:center" %)
445 [[image:20230515-8.png]]
446
447 ② When P02-07=1
448
449 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).
450
451 (% style="text-align:center" %)
452 [[image:20230515-9.png]]
453
454 Figure 7-9 Flow chart of gain switching when P02-07=1
455
456 |(% style="width:72px" %)**P02-08**|(% style="width:146px" %)**Content**|**Diagram**
457 |(% style="width:72px" %)0|(% style="width:146px" %)Fixed use of the first gain|~-~-
458 |(% style="width:72px" %)1|(% style="width:146px" %)Switching with DI|~-~-
459 |(% style="width:72px" %)(((
460
461
462
463
464
465
466 2
467 )))|(% style="width:146px" %)(((
468
469
470
471
472
473
474 Large torque command
475 )))|[[image:image-20230515140641-1.png]]
476 |(% style="width:72px" %)(((
477
478
479
480
481
482
483
484 3
485 )))|(% style="width:146px" %)Large actual torque|[[image:image-20230515140641-2.png]]
486 |(% style="width:72px" %)(((
487
488
489
490
491
492
493 4
494 )))|(% style="width:146px" %)(((
495
496
497
498
499
500
501 Large speed command
502 )))|[[image:image-20230515140641-3.png]]
503
504 |(% style="width:74px" %)**P02-08**|(% style="width:176px" %)**Content**|**Diagram**
505 |(% style="width:74px" %)(((
506
507
508
509
510
511 5
512 )))|(% style="width:176px" %)(((
513
514
515
516
517
518 Fast actual speed
519 )))|(((
520
521
522 [[image:image-20230515140641-4.png]]
523 )))
524 |(% style="width:74px" %)(((
525
526
527
528
529
530
531
532 6
533 )))|(% style="width:176px" %)(((
534
535
536
537
538
539
540
541 Speed command change rate is large
542 )))|[[image:image-20230515140641-5.png]]
543 |(% style="width:74px" %)(((
544
545
546
547
548
549
550 7
551
552
553 )))|(% style="width:176px" %)(((
554
555
556
557
558
559
560 Large position deviation
561 )))|[[image:image-20230515140641-6.png]]
562 |(% style="width:74px" %)(((
563
564
565
566
567
568 8
569 )))|(% style="width:176px" %)(((
570
571
572
573
574
575 Position command
576 )))|[[image:image-20230515140641-7.png]]
577
578 |(% style="width:73px" %)(((
579
580
581
582
583
584
585 9
586 )))|(% style="width:154px" %)(((
587
588
589
590
591
592
593 Positioning completed
594 )))|[[image:image-20230515140641-8.png]]
595 |(% style="width:73px" %)(((
596
597
598 10
599
600
601 )))|(% style="width:154px" %)(((
602
603
604 Position command + actual speed
605 )))|(((
606
607
608 Refer to the chart below
609 )))
610
611 (% style="text-align:center" %)
612 [[image:20230515-10.png]]
613
614 Figure 7-10 P02-08=10 Position command + actual speed gain description
615
616 (2) Description of related parameters
617
618 |(% rowspan="2" style="width:68px" %)
619 **P02-07**|(% style="width:150px" %)**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
620 |(% style="width:150px" %)The second gain switching mode|Operation setting|Effective immediately|0|0 to 1|Gain control|
621 |(% colspan="8" %)(((
622 Set the switching mode of the second gain.
623
624 |**Setting value**|**Function**
625 |0|(((
626 The first gain is used by default. Switching using DI function 10 (GAIN-SEL, gain switching):
627
628 DI logic invalid: PI control;
629
630 DI logic valid: PI control.
631 )))
632 |1|The first gain and the second gain are switched by the setting value of P02-08.
633 )))
634
635 |(% rowspan="2" %)
636 **P02-08**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
637 |Gain switching condition selection|Operation setting|Effective immediately|0|0 to 10|Gain control|
638 |(% colspan="8" %)(((
639 Set the conditions for gain switching.
640
641 |Setting value|Gain switching conditions|Details
642 |0|The default is the first gain|Fixed use of the first gain
643 |1|Switch by DI port|(((
644 Use DI function 10 (GAIN-SEL, gain switching);
645
646 DI logic is invalid: the first gain (P02-01~~P02-03);
647
648 DI logic is valid: the second gain (P02-04~~P02-06).
649 )))
650 |2|Large torque command|(((
651 In the previous first gain, when the absolute value of torque command is greater than (grade + hysteresis), the second gain is switched;
652
653 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.
654
655
656 )))
657 |3|Large actual torque|(((
658 In the previous first gain, when the absolute value of actual torque is greater than ( grade + hysteresis ), the second gain is switched;
659
660 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 .
661
662
663 )))
664 |4|Large speed command|(((
665 In the previous first gain, when the absolute value of speed command is greater than (grade + hysteresis), the second gain is switched;
666
667 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 .
668
669
670 )))
671 |5|Large actual speed|(((
672 In the previous first gain, when the absolute value of actual speed is greater than (grade + hysteresis), the second gain is switched;
673
674 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 .
675
676
677 )))
678 |(((
679
680
681 6
682 )))|(((
683
684
685 Large rate of change in speed command
686 )))|(((
687 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;
688
689 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 .
690
691
692 )))
693 |(((
694
695
696 7
697 )))|(((
698
699
700 Large position deviation
701 )))|(((
702 In the previous first gain, when the absolute value of position deviation is greater than (grade + hysteresis), the second gain is switched;
703
704 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 .
705 )))
706 |8|Position command|(((
707 In the previous first gain, if the position command is not 0, switch to the second gain;
708
709 In the previous second gain, if the position command is 0 and the duration is greater than [P02-13], the first gain is returned.
710 )))
711 |(((
712
713
714 9
715 )))|(((
716
717
718 Positioning complete
719 )))|(((
720 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.
721
722
723 )))
724 |(((
725
726
727 10
728 )))|(((
729
730
731 Position command + actual speed
732 )))|(((
733 In the previous first gain, if the position command is not 0, the second gain is switched;
734
735 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).
736
737
738 )))
739
740
741 )))
742
743 |(% rowspan="2" %)
744 **P02-13**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
745 |Delay Time for Gain Switching|Operation setting|Effective immediately|20|0 to 10000|Gain control|0.1ms
746 |(% colspan="8" %)(((
747 The duration of the switching condition required for the second gain to switch back to the first gain.
748
749 [[image:image-20230515140953-9.png]]
750
751 **✎**Note: This parameter is only valid when the second gain is switched back to the first gain.
752 )))
753
754 |(% rowspan="2" %)
755 **P02-14**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
756 |Gain switching grade|Operation setting|Effective immediately|50|0 to 20000|Gain control|According to the switching conditions
757 |(% colspan="8" %)(((
758 Set the grade of the gain condition. The generation of the actual switching action is affected by the two conditions of grade and hysteresis.
759
760 [[image:image-20230515140953-10.png]]
761 )))
762
763 |(% rowspan="2" %)
764 **P02-15**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
765 |Gain switching hysteresis|Operation setting|Effective immediately|20|0 to 20000|Gain control|According to the switching conditions
766 |(% colspan="8" %)(((
767 Set the hysteresis to meet the gain switching condition.
768
769 [[image:image-20230515140953-11.png]]
770 )))
771
772 |(% rowspan="2" %)
773 **P02-16**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
774 |Position loop gain switching time|Operation setting|Effective immediately|30|0 to 10000|Gain control|0.1ms
775 |(% colspan="8" %)(((
776 Set the time for switching from the first position loop (P02-01) to the second position loop (P02-04) in the position control mode.
777
778 [[image:image-20230515140953-12.png]]
779
780 If P02-04≤P02-01, then P02-16 is invalid, and the second gain is switched from the first gain immediately.
781 )))
782
783 == **Model Tracking Control Function** ==
784
785 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:
786
787 (% style="text-align:center" %)
788 [[image:20230515-7.png]]
789
790 The usage method and conditions of model tracking control:
791
792 ~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.
793
794 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).
795
796 3. Set P2-20=1 to enable the function of model tracking control.
797
798 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.
799
800 5. After the responsiveness meets the requirements, user can adjust the parameters appropriately to increase the load rigidity level P3-2.
801
802 **✎Note**: Model tracking control is only available in position mode, and cannot be used in other modes.
803
804 |**Function code**|**Name**|(((
805 **Setting**
806
807 **method**
808 )))|(((
809 **Effective**
810
811 **time**
812 )))|**Default**|**Range**|**Definition**|**Unit**
813 |P2-20|Model tracking control function|Shutdown setting|(((
814 Effective
815
816 immediately
817 )))|0|0 to 1|When the function code is set to 1, enable the model tracking control function.|
818 |P2-21|Model tracking control gain|Shutdown setting|(((
819 Effective
820
821 immediately
822 )))|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
823 |P2-22|Model tracking control gain compensation|Shutdown setting|(((
824 Effective
825
826 immediately
827 )))|1000|500 to 2000|0.10%
828
829 |**Function code**|**Name**|(((
830 **Setting**
831
832 **method**
833 )))|(((
834 **Effective**
835
836 **time**
837 )))|**Default**|**Range**|**Definition**|**Unit**
838 |P2-23|Model tracking control forward rotation bias|(((
839 Operation
840
841 setting
842 )))|(((
843 Effective
844
845 immediately
846 )))|1000|0 to 10000|(% rowspan="2" %)Torque feedforward size in the positive and reverse direction under model tracking control|0.10%
847 |P2-24|Model tracking control reverses rotation bias|(((
848 Operation
849
850 setting
851 )))|(((
852 Effective
853
854 immediately
855 )))|1000|0 to 10000|0.10%
856 |P2-25|Model tracking control speed feedforward compensation|Operation setting|(((
857 Effective
858
859 immediately
860 )))|1000|0 to 10000|The size of the speed feedforward under model tracking control|0.10%
861
862 Please refer to the following for an example of the procedure of adjusting servo gain.
863
864 |**Step**|**Content**
865 |1|Please try to set the correct load inertia ratio parameter P3-1.
866 |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.
867 |3|Turn on the model tracking function, set P2-20 to 1.
868 |4|Increase the model tracking gain P2-21 within the range of no overshoot and vibration occur.
869 |5|If the rigidity level of step 2 is set relatively low, user can properly increase the rigidity level P3-2.
870 |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.
871
872 == **Gain switching** ==
873
874 Gain switching function:
875
876 ●Switch to a lower gain in the motor stationary (servo enabled)state to suppress vibration;
877
878 ●Switch to a higher gain in the motor stationary state to shorten the positioning time;
879
880 ●Switch to a higher gain in the motor running state to get better command tracking performance;
881
882 ●Switch different gain settings by external signals depending on the load connected.
883
884 (1) Gain switching parameter setting
885
886 ①When P02-07=0
887
888 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).
889
890 (% style="text-align:center" %)
891 [[image:20230515-8.png]]
892
893 ② When P02-07=1
894
895 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).
896
897 (% style="text-align:center" %)
898 [[image:20230515-9.png]]
899
900 Figure 7-9 Flow chart of gain switching when P02-07=1
901
902 |(% style="width:72px" %)**P02-08**|(% style="width:146px" %)**Content**|**Diagram**
903 |(% style="width:72px" %)0|(% style="width:146px" %)Fixed use of the first gain|~-~-
904 |(% style="width:72px" %)1|(% style="width:146px" %)Switching with DI|~-~-
905 |(% style="width:72px" %)(((
906
907
908
909
910
911
912 2
913 )))|(% style="width:146px" %)(((
914
915
916
917
918
919
920 Large torque command
921 )))|[[image:image-20230515140641-1.png]]
922 |(% style="width:72px" %)(((
923
924
925
926
927
928
929
930 3
931 )))|(% style="width:146px" %)Large actual torque|[[image:image-20230515140641-2.png]]
932 |(% style="width:72px" %)(((
933
934
935
936
937
938
939 4
940 )))|(% style="width:146px" %)(((
941
942
943
944
945
946
947 Large speed command
948 )))|[[image:image-20230515140641-3.png]]
949
950 |(% style="width:74px" %)**P02-08**|(% style="width:176px" %)**Content**|**Diagram**
951 |(% style="width:74px" %)(((
952
953
954
955
956
957 5
958 )))|(% style="width:176px" %)(((
959
960
961
962
963
964 Fast actual speed
965 )))|(((
966
967
968 [[image:image-20230515140641-4.png]]
969 )))
970 |(% style="width:74px" %)(((
971
972
973
974
975
976
977
978 6
979 )))|(% style="width:176px" %)(((
980
981
982
983
984
985
986
987 Speed command change rate is large
988 )))|[[image:image-20230515140641-5.png]]
989 |(% style="width:74px" %)(((
990
991
992
993
994
995
996 7
997
998
999 )))|(% style="width:176px" %)(((
1000
1001
1002
1003
1004
1005
1006 Large position deviation
1007 )))|[[image:image-20230515140641-6.png]]
1008 |(% style="width:74px" %)(((
1009
1010
1011
1012
1013
1014 8
1015 )))|(% style="width:176px" %)(((
1016
1017
1018
1019
1020
1021 Position command
1022 )))|[[image:image-20230515140641-7.png]]
1023
1024 |(% style="width:73px" %)(((
1025
1026
1027
1028
1029
1030
1031 9
1032 )))|(% style="width:154px" %)(((
1033
1034
1035
1036
1037
1038
1039 Positioning completed
1040 )))|[[image:image-20230515140641-8.png]]
1041 |(% style="width:73px" %)(((
1042
1043
1044 10
1045
1046
1047 )))|(% style="width:154px" %)(((
1048
1049
1050 Position command + actual speed
1051 )))|(((
1052
1053
1054 Refer to the chart below
1055 )))
1056
1057 (% style="text-align:center" %)
1058 [[image:20230515-10.png]]
1059
1060 Figure 7-10 P02-08=10 Position command + actual speed gain description
1061
1062 (2) Description of related parameters
1063
1064 |(% rowspan="2" style="width:68px" %)
1065 **P02-07**|(% style="width:150px" %)**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1066 |(% style="width:150px" %)The second gain switching mode|Operation setting|Effective immediately|0|0 to 1|Gain control|
1067 |(% colspan="8" %)(((
1068 Set the switching mode of the second gain.
1069
1070 |**Setting value**|**Function**
1071 |0|(((
1072 The first gain is used by default. Switching using DI function 10 (GAIN-SEL, gain switching):
1073
1074 DI logic invalid: PI control;
1075
1076 DI logic valid: PI control.
1077 )))
1078 |1|The first gain and the second gain are switched by the setting value of P02-08.
1079 )))
1080
1081 |(% rowspan="2" %)
1082 **P02-08**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1083 |Gain switching condition selection|Operation setting|Effective immediately|0|0 to 10|Gain control|
1084 |(% colspan="8" %)(((
1085 Set the conditions for gain switching.
1086
1087 |Setting value|Gain switching conditions|Details
1088 |0|The default is the first gain|Fixed use of the first gain
1089 |1|Switch by DI port|(((
1090 Use DI function 10 (GAIN-SEL, gain switching);
1091
1092 DI logic is invalid: the first gain (P02-01~~P02-03);
1093
1094 DI logic is valid: the second gain (P02-04~~P02-06).
1095 )))
1096 |2|Large torque command|(((
1097 In the previous first gain, when the absolute value of torque command is greater than (grade + hysteresis), the second gain is switched;
1098
1099 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.
1100
1101
1102 )))
1103 |3|Large actual torque|(((
1104 In the previous first gain, when the absolute value of actual torque is greater than ( grade + hysteresis ), the second gain is switched;
1105
1106 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 .
1107
1108
1109 )))
1110 |4|Large speed command|(((
1111 In the previous first gain, when the absolute value of speed command is greater than (grade + hysteresis), the second gain is switched;
1112
1113 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 .
1114
1115
1116 )))
1117 |5|Large actual speed|(((
1118 In the previous first gain, when the absolute value of actual speed is greater than (grade + hysteresis), the second gain is switched;
1119
1120 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 .
1121
1122
1123 )))
1124 |(((
1125
1126
1127 6
1128 )))|(((
1129
1130
1131 Large rate of change in speed command
1132 )))|(((
1133 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;
1134
1135 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 .
1136
1137
1138 )))
1139 |(((
1140
1141
1142 7
1143 )))|(((
1144
1145
1146 Large position deviation
1147 )))|(((
1148 In the previous first gain, when the absolute value of position deviation is greater than (grade + hysteresis), the second gain is switched;
1149
1150 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 .
1151 )))
1152 |8|Position command|(((
1153 In the previous first gain, if the position command is not 0, switch to the second gain;
1154
1155 In the previous second gain, if the position command is 0 and the duration is greater than [P02-13], the first gain is returned.
1156 )))
1157 |(((
1158
1159
1160 9
1161 )))|(((
1162
1163
1164 Positioning complete
1165 )))|(((
1166 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.
1167
1168
1169 )))
1170 |(((
1171
1172
1173 10
1174 )))|(((
1175
1176
1177 Position command + actual speed
1178 )))|(((
1179 In the previous first gain, if the position command is not 0, the second gain is switched;
1180
1181 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).
1182
1183
1184 )))
1185
1186
1187 )))
1188
1189 |(% rowspan="2" %)
1190 **P02-13**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1191 |Delay Time for Gain Switching|Operation setting|Effective immediately|20|0 to 10000|Gain control|0.1ms
1192 |(% colspan="8" %)(((
1193 The duration of the switching condition required for the second gain to switch back to the first gain.
1194
1195 [[image:image-20230515140953-9.png]]
1196
1197 **✎**Note: This parameter is only valid when the second gain is switched back to the first gain.
1198 )))
1199
1200 |(% rowspan="2" %)
1201 **P02-14**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1202 |Gain switching grade|Operation setting|Effective immediately|50|0 to 20000|Gain control|According to the switching conditions
1203 |(% colspan="8" %)(((
1204 Set the grade of the gain condition. The generation of the actual switching action is affected by the two conditions of grade and hysteresis.
1205
1206 [[image:image-20230515140953-10.png]]
1207 )))
1208
1209 |(% rowspan="2" %)
1210 **P02-15**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1211 |Gain switching hysteresis|Operation setting|Effective immediately|20|0 to 20000|Gain control|According to the switching conditions
1212 |(% colspan="8" %)(((
1213 Set the hysteresis to meet the gain switching condition.
1214
1215 [[image:image-20230515140953-11.png]]
1216 )))
1217
1218 |(% rowspan="2" %)
1219 **P02-16**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1220 |Position loop gain switching time|Operation setting|Effective immediately|30|0 to 10000|Gain control|0.1ms
1221 |(% colspan="8" %)(((
1222 Set the time for switching from the first position loop (P02-01) to the second position loop (P02-04) in the position control mode.
1223
1224 [[image:image-20230515140953-12.png]]
1225
1226 If P02-04≤P02-01, then P02-16 is invalid, and the second gain is switched from the first gain immediately.
1227 )))
1228
1229 = **Mechanical resonance suppression** =
1230
1231 == Mechanical resonance suppression methods ==
1232
1233 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.
1234
1235 **Torque instruction filter**
1236
1237 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:
1238
1239 (% style="text-align:center" %)
1240 [[image:image-20220706155820-5.jpeg||class="img-thumbnail"]]
1241
1242 **Notch filter**
1243
1244 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__.
1245
1246 == Notch filter ==
1247
1248 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.
1249
1250 **Width grade of notch filter**
1251
1252 The notch width grade is used to express the ratio of the notch width to the center frequency of the notch:
1253
1254 (% style="text-align:center" %)
1255 [[image:image-20220706155836-6.png||class="img-thumbnail"]]
1256
1257 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.
1258
1259 **Depth grade of notch filter**
1260
1261 The depth grade of notch filter represents the ratio relationship between input and output at center frequency.
1262
1263 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__.
1264
1265 (% style="text-align:center" %)
1266 (((
1267 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
1268 [[Figure 7-7 Notch characteristics, notch width, and notch depth>>image:image-20220608174259-3.png||id="Iimage-20220608174259-3.png"]]
1269 )))
1270
1271
1272 (% style="text-align:center" %)
1273 (((
1274 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
1275 [[Figure 7-8 Frequency characteristics of notch filter>>image:image-20220706160046-9.png||id="Iimage-20220706160046-9.png"]]
1276 )))
1277
1278
1279 (% class="table-bordered" %)
1280 |=(% 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;" %)(((
1281 **Setting method**
1282 )))|=(% style="text-align: center; vertical-align: middle; width: 121px;" %)(((
1283 **Effective time**
1284 )))|=(% 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**
1285 |=(% 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" %)(((
1286 Operation setting
1287 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1288 Effective immediately
1289 )))|(% 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
1290 |=(% 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" %)(((
1291 Operation setting
1292 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1293 Effective immediately
1294 )))|(% 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" %)(((
1295 1. 0: all truncated
1296 1. 100: all passed
1297 )))|(% style="text-align:center; vertical-align:middle; width:96px" %)-
1298 |=(% 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" %)(((
1299 Operation setting
1300 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1301 Effective immediately
1302 )))|(% 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" %)(((
1303 1. 0: 0.5 times the bandwidth
1304 1. 4: 1 times the bandwidth
1305 1. 8: 2 times the bandwidth
1306 1. 12: 4 times the bandwidth
1307 )))|(% style="text-align:center; vertical-align:middle; width:96px" %)-
1308 |=(% 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" %)(((
1309 Operation setting
1310 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1311 Effective immediately
1312 )))|(% 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
1313 |=(% 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" %)(((
1314 Operation setting
1315 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1316 Effective immediately
1317 )))|(% 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" %)(((
1318 1. 0: all truncated
1319 1. 100: all passed
1320 )))|(% style="text-align:center; vertical-align:middle; width:96px" %)-
1321 |=(% 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" %)(((
1322 Operation setting
1323 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1324 Effective immediately
1325 )))|(% 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" %)(((
1326 1. 0: 0.5 times the bandwidth
1327 1. 4: 1 times the bandwidth
1328 1. 8: 2 times the bandwidth
1329 1. 12: 4 times the bandwidth
1330 )))|(% style="text-align:center; vertical-align:middle; width:96px" %)-
1331
1332 Table 7-11 Notch filter function code parameters
1333 ~)~)~)