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Wiki source code of 07 Adjustments

Version 22.1 by Karen on 2023/05/15 14:54
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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 )))|(((
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|Shutdown setting|(((
390 Effective immediately
391 )))|1000|(% style="text-align:center; vertical-align:middle; width:107px" %)500 to 2000|(% style="text-align:center; vertical-align:middle" %)0.10%
392
393 (% class="table-bordered" %)
394 |=(% 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;" %)(((
395 **Setting method**
396 )))|=(% style="text-align: center; vertical-align: middle; width: 128px;" %)(((
397 **Effective time**
398 )))|=(% 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**
399 |=(% 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|(((
400 Operation setting
401 )))|(((
402 Effective immediately
403 )))|(% 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%
404 |=(% 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|(((
405 Operation setting
406 )))|(((
407 Effective immediately
408 )))|1000|(% style="text-align:center; vertical-align:middle; width:107px" %)0 to 10000|0.10%
409 |=(% 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|(((
410 Effective immediately
411 )))|(% 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%
412
413 Please refer to the following for an example of the procedure of adjusting servo gain.
414
415 |**Step**|** Content**
416 |1|Please try to set the correct load inertia ratio parameter P3-1.
417 |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.
418 |3|Turn on the model tracking function, set P2-20 to 1.
419 |4|Increase the model tracking gain P2-21 within the range of no overshoot and vibration occurring.
420 |5|If the rigidity level of step 2 is set relatively low, user can properly increase the rigidity level P3-2.
421 |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.