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Wiki source code of 07 Adjustments

Version 19.3 by Karen on 2023/05/15 14:27
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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 **✎Note**: Model tracking control is only available in position mode, and cannot be used in other modes.
368
369 (% class="table-bordered" %)
370 |=(% 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;" %)(((
371 **Setting method**
372 )))|=(% style="text-align: center; vertical-align: middle; width: 128px;" %)(((
373 **Effective time**
374 )))|=(% 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**
375 |=(% 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" %)Shutdown setting|(% style="text-align:center; vertical-align:middle; width:128px" %)(((
376 Effective immediately
377 )))|0|0 to 1|When the function code is set to 1, enable the model tracking control function.|
378 |P2-21|Model tracking control gain|Shutdown setting|(((
379 Effective immediately
380 )))|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
381 |P2-22|Model tracking control gain compensation|Shutdown setting|(((
382 Effective immediately
383 )))|1000|500 to 2000|0.10%
384
385 (% class="table-bordered" %)
386 |=(% 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;" %)(((
387 **Setting method**
388 )))|=(% style="text-align: center; vertical-align: middle; width: 128px;" %)(((
389 **Effective time**
390 )))|=(% 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**
391 |P2-23|Model tracking control forward rotation bias|(((
392 Operation setting
393 )))|(((
394 Effective immediately
395 )))|1000|0 to 10000|(% rowspan="2" %)Torque feedforward size in the positive and reverse direction under model tracking control|0.10%
396 |P2-24|Model tracking control reverses rotation bias|(((
397 Operation setting
398 )))|(((
399 Effective immediately
400 )))|1000|0 to 10000|0.10%
401 |P2-25|Model tracking control speed feedforward compensation|Operation setting|(((
402 Effective immediately
403 )))|1000|0 to 10000|The size of the speed feedforward under model tracking control|0.10%
404
405 Please refer to the following for an example of the procedure of adjusting servo gain.
406
407 |**Step**|**Content**
408 |1|Please try to set the correct load inertia ratio parameter P3-1.
409 |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.
410 |3|Turn on the model tracking function, set P2-20 to 1.
411 |4|Increase the model tracking gain P2-21 within the range of no overshoot and vibration occur.
412 |5|If the rigidity level of step 2 is set relatively low, user can properly increase the rigidity level P3-2.
413 |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.
414
415 == **Gain switching** ==
416
417 Gain switching function:
418
419 ●Switch to a lower gain in the motor stationary (servo enabled)state to suppress vibration;
420
421 ●Switch to a higher gain in the motor stationary state to shorten the positioning time;
422
423 ●Switch to a higher gain in the motor running state to get better command tracking performance;
424
425 ●Switch different gain settings by external signals depending on the load connected.
426
427 (1) Gain switching parameter setting
428
429 ①When P02-07=0
430
431 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).
432
433 (% style="text-align:center" %)
434 [[image:20230515-8.png]]
435
436 ② When P02-07=1
437
438 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).
439
440 (% style="text-align:center" %)
441 [[image:20230515-9.png]]
442
443 Figure 7-9 Flow chart of gain switching when P02-07=1
444
445 |(% style="width:72px" %)**P02-08**|(% style="width:146px" %)**Content**|**Diagram**
446 |(% style="width:72px" %)0|(% style="width:146px" %)Fixed use of the first gain|~-~-
447 |(% style="width:72px" %)1|(% style="width:146px" %)Switching with DI|~-~-
448 |(% style="width:72px" %)(((
449
450
451
452
453
454
455 2
456 )))|(% style="width:146px" %)(((
457
458
459
460
461
462
463 Large torque command
464 )))|[[image:image-20230515140641-1.png]]
465 |(% style="width:72px" %)(((
466
467
468
469
470
471
472
473 3
474 )))|(% style="width:146px" %)Large actual torque|[[image:image-20230515140641-2.png]]
475 |(% style="width:72px" %)(((
476
477
478
479
480
481
482 4
483 )))|(% style="width:146px" %)(((
484
485
486
487
488
489
490 Large speed command
491 )))|[[image:image-20230515140641-3.png]]
492
493 |(% style="width:74px" %)**P02-08**|(% style="width:176px" %)**Content**|**Diagram**
494 |(% style="width:74px" %)(((
495
496
497
498
499
500 5
501 )))|(% style="width:176px" %)(((
502
503
504
505
506
507 Fast actual speed
508 )))|(((
509
510
511 [[image:image-20230515140641-4.png]]
512 )))
513 |(% style="width:74px" %)(((
514
515
516
517
518
519
520
521 6
522 )))|(% style="width:176px" %)(((
523
524
525
526
527
528
529
530 Speed command change rate is large
531 )))|[[image:image-20230515140641-5.png]]
532 |(% style="width:74px" %)(((
533
534
535
536
537
538
539 7
540
541
542 )))|(% style="width:176px" %)(((
543
544
545
546
547
548
549 Large position deviation
550 )))|[[image:image-20230515140641-6.png]]
551 |(% style="width:74px" %)(((
552
553
554
555
556
557 8
558 )))|(% style="width:176px" %)(((
559
560
561
562
563
564 Position command
565 )))|[[image:image-20230515140641-7.png]]
566
567 |(% style="width:73px" %)(((
568
569
570
571
572
573
574 9
575 )))|(% style="width:154px" %)(((
576
577
578
579
580
581
582 Positioning completed
583 )))|[[image:image-20230515140641-8.png]]
584 |(% style="width:73px" %)(((
585
586
587 10
588
589
590 )))|(% style="width:154px" %)(((
591
592
593 Position command + actual speed
594 )))|(((
595
596
597 Refer to the chart below
598 )))
599
600 (% style="text-align:center" %)
601 [[image:20230515-10.png]]
602
603 Figure 7-10 P02-08=10 Position command + actual speed gain description
604
605 (2) Description of related parameters
606
607 |(% rowspan="2" style="width:68px" %)
608 **P02-07**|(% style="width:150px" %)**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
609 |(% style="width:150px" %)The second gain switching mode|Operation setting|Effective immediately|0|0 to 1|Gain control|
610 |(% colspan="8" %)(((
611 Set the switching mode of the second gain.
612
613 |**Setting value**|**Function**
614 |0|(((
615 The first gain is used by default. Switching using DI function 10 (GAIN-SEL, gain switching):
616
617 DI logic invalid: PI control;
618
619 DI logic valid: PI control.
620 )))
621 |1|The first gain and the second gain are switched by the setting value of P02-08.
622 )))
623
624 |(% rowspan="2" %)
625 **P02-08**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
626 |Gain switching condition selection|Operation setting|Effective immediately|0|0 to 10|Gain control|
627 |(% colspan="8" %)(((
628 Set the conditions for gain switching.
629
630 |Setting value|Gain switching conditions|Details
631 |0|The default is the first gain|Fixed use of the first gain
632 |1|Switch by DI port|(((
633 Use DI function 10 (GAIN-SEL, gain switching);
634
635 DI logic is invalid: the first gain (P02-01~~P02-03);
636
637 DI logic is valid: the second gain (P02-04~~P02-06).
638 )))
639 |2|Large torque command|(((
640 In the previous first gain, when the absolute value of torque command is greater than (grade + hysteresis), the second gain is switched;
641
642 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.
643
644
645 )))
646 |3|Large actual torque|(((
647 In the previous first gain, when the absolute value of actual torque is greater than ( grade + hysteresis ), the second gain is switched;
648
649 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 .
650
651
652 )))
653 |4|Large speed command|(((
654 In the previous first gain, when the absolute value of speed command is greater than (grade + hysteresis), the second gain is switched;
655
656 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 .
657
658
659 )))
660 |5|Large actual speed|(((
661 In the previous first gain, when the absolute value of actual speed is greater than (grade + hysteresis), the second gain is switched;
662
663 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 .
664
665
666 )))
667 |(((
668
669
670 6
671 )))|(((
672
673
674 Large rate of change in speed command
675 )))|(((
676 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;
677
678 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 .
679
680
681 )))
682 |(((
683
684
685 7
686 )))|(((
687
688
689 Large position deviation
690 )))|(((
691 In the previous first gain, when the absolute value of position deviation is greater than (grade + hysteresis), the second gain is switched;
692
693 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 .
694 )))
695 |8|Position command|(((
696 In the previous first gain, if the position command is not 0, switch to the second gain;
697
698 In the previous second gain, if the position command is 0 and the duration is greater than [P02-13], the first gain is returned.
699 )))
700 |(((
701
702
703 9
704 )))|(((
705
706
707 Positioning complete
708 )))|(((
709 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.
710
711
712 )))
713 |(((
714
715
716 10
717 )))|(((
718
719
720 Position command + actual speed
721 )))|(((
722 In the previous first gain, if the position command is not 0, the second gain is switched;
723
724 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).
725
726
727 )))
728
729
730 )))
731
732 |(% rowspan="2" %)
733 **P02-13**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
734 |Delay Time for Gain Switching|Operation setting|Effective immediately|20|0 to 10000|Gain control|0.1ms
735 |(% colspan="8" %)(((
736 The duration of the switching condition required for the second gain to switch back to the first gain.
737
738 [[image:image-20230515140953-9.png]]
739
740 **✎**Note: This parameter is only valid when the second gain is switched back to the first gain.
741 )))
742
743 |(% rowspan="2" %)
744 **P02-14**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
745 |Gain switching grade|Operation setting|Effective immediately|50|0 to 20000|Gain control|According to the switching conditions
746 |(% colspan="8" %)(((
747 Set the grade of the gain condition. The generation of the actual switching action is affected by the two conditions of grade and hysteresis.
748
749 [[image:image-20230515140953-10.png]]
750 )))
751
752 |(% rowspan="2" %)
753 **P02-15**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
754 |Gain switching hysteresis|Operation setting|Effective immediately|20|0 to 20000|Gain control|According to the switching conditions
755 |(% colspan="8" %)(((
756 Set the hysteresis to meet the gain switching condition.
757
758 [[image:image-20230515140953-11.png]]
759 )))
760
761 |(% rowspan="2" %)
762 **P02-16**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
763 |Position loop gain switching time|Operation setting|Effective immediately|30|0 to 10000|Gain control|0.1ms
764 |(% colspan="8" %)(((
765 Set the time for switching from the first position loop (P02-01) to the second position loop (P02-04) in the position control mode.
766
767 [[image:image-20230515140953-12.png]]
768
769 If P02-04≤P02-01, then P02-16 is invalid, and the second gain is switched from the first gain immediately.
770 )))
771
772
773
774
775 == **Model Tracking Control Function** ==
776
777 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:
778
779 (% style="text-align:center" %)
780 [[image:20230515-7.png]]
781
782 The usage method and conditions of model tracking control:
783
784 ~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.
785
786 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).
787
788 3. Set P2-20=1 to enable the function of model tracking control.
789
790 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.
791
792 5. After the responsiveness meets the requirements, user can adjust the parameters appropriately to increase the load rigidity level P3-2.
793
794 **✎Note**: Model tracking control is only available in position mode, and cannot be used in other modes.
795
796 |**Function code**|**Name**|(((
797 **Setting**
798
799 **method**
800 )))|(((
801 **Effective**
802
803 **time**
804 )))|**Default**|**Range**|**Definition**|**Unit**
805 |P2-20|Model tracking control function|Shutdown setting|(((
806 Effective
807
808 immediately
809 )))|0|0 to 1|When the function code is set to 1, enable the model tracking control function.|
810 |P2-21|Model tracking control gain|Shutdown setting|(((
811 Effective
812
813 immediately
814 )))|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
815 |P2-22|Model tracking control gain compensation|Shutdown setting|(((
816 Effective
817
818 immediately
819 )))|1000|500 to 2000|0.10%
820
821 |**Function code**|**Name**|(((
822 **Setting**
823
824 **method**
825 )))|(((
826 **Effective**
827
828 **time**
829 )))|**Default**|**Range**|**Definition**|**Unit**
830 |P2-23|Model tracking control forward rotation bias|(((
831 Operation
832
833 setting
834 )))|(((
835 Effective
836
837 immediately
838 )))|1000|0 to 10000|(% rowspan="2" %)Torque feedforward size in the positive and reverse direction under model tracking control|0.10%
839 |P2-24|Model tracking control reverses rotation bias|(((
840 Operation
841
842 setting
843 )))|(((
844 Effective
845
846 immediately
847 )))|1000|0 to 10000|0.10%
848 |P2-25|Model tracking control speed feedforward compensation|Operation setting|(((
849 Effective
850
851 immediately
852 )))|1000|0 to 10000|The size of the speed feedforward under model tracking control|0.10%
853
854 Please refer to the following for an example of the procedure of adjusting servo gain.
855
856 |**Step**|**Content**
857 |1|Please try to set the correct load inertia ratio parameter P3-1.
858 |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.
859 |3|Turn on the model tracking function, set P2-20 to 1.
860 |4|Increase the model tracking gain P2-21 within the range of no overshoot and vibration occur.
861 |5|If the rigidity level of step 2 is set relatively low, user can properly increase the rigidity level P3-2.
862 |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.
863
864 == **Gain switching** ==
865
866 Gain switching function:
867
868 ●Switch to a lower gain in the motor stationary (servo enabled)state to suppress vibration;
869
870 ●Switch to a higher gain in the motor stationary state to shorten the positioning time;
871
872 ●Switch to a higher gain in the motor running state to get better command tracking performance;
873
874 ●Switch different gain settings by external signals depending on the load connected.
875
876 (1) Gain switching parameter setting
877
878 ①When P02-07=0
879
880 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).
881
882 (% style="text-align:center" %)
883 [[image:20230515-8.png]]
884
885 ② When P02-07=1
886
887 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).
888
889 (% style="text-align:center" %)
890 [[image:20230515-9.png]]
891
892 Figure 7-9 Flow chart of gain switching when P02-07=1
893
894 |(% style="width:72px" %)**P02-08**|(% style="width:146px" %)**Content**|**Diagram**
895 |(% style="width:72px" %)0|(% style="width:146px" %)Fixed use of the first gain|~-~-
896 |(% style="width:72px" %)1|(% style="width:146px" %)Switching with DI|~-~-
897 |(% style="width:72px" %)(((
898
899
900
901
902
903
904 2
905 )))|(% style="width:146px" %)(((
906
907
908
909
910
911
912 Large torque command
913 )))|[[image:image-20230515140641-1.png]]
914 |(% style="width:72px" %)(((
915
916
917
918
919
920
921
922 3
923 )))|(% style="width:146px" %)Large actual torque|[[image:image-20230515140641-2.png]]
924 |(% style="width:72px" %)(((
925
926
927
928
929
930
931 4
932 )))|(% style="width:146px" %)(((
933
934
935
936
937
938
939 Large speed command
940 )))|[[image:image-20230515140641-3.png]]
941
942 |(% style="width:74px" %)**P02-08**|(% style="width:176px" %)**Content**|**Diagram**
943 |(% style="width:74px" %)(((
944
945
946
947
948
949 5
950 )))|(% style="width:176px" %)(((
951
952
953
954
955
956 Fast actual speed
957 )))|(((
958
959
960 [[image:image-20230515140641-4.png]]
961 )))
962 |(% style="width:74px" %)(((
963
964
965
966
967
968
969
970 6
971 )))|(% style="width:176px" %)(((
972
973
974
975
976
977
978
979 Speed command change rate is large
980 )))|[[image:image-20230515140641-5.png]]
981 |(% style="width:74px" %)(((
982
983
984
985
986
987
988 7
989
990
991 )))|(% style="width:176px" %)(((
992
993
994
995
996
997
998 Large position deviation
999 )))|[[image:image-20230515140641-6.png]]
1000 |(% style="width:74px" %)(((
1001
1002
1003
1004
1005
1006 8
1007 )))|(% style="width:176px" %)(((
1008
1009
1010
1011
1012
1013 Position command
1014 )))|[[image:image-20230515140641-7.png]]
1015
1016 |(% style="width:73px" %)(((
1017
1018
1019
1020
1021
1022
1023 9
1024 )))|(% style="width:154px" %)(((
1025
1026
1027
1028
1029
1030
1031 Positioning completed
1032 )))|[[image:image-20230515140641-8.png]]
1033 |(% style="width:73px" %)(((
1034
1035
1036 10
1037
1038
1039 )))|(% style="width:154px" %)(((
1040
1041
1042 Position command + actual speed
1043 )))|(((
1044
1045
1046 Refer to the chart below
1047 )))
1048
1049 (% style="text-align:center" %)
1050 [[image:20230515-10.png]]
1051
1052 Figure 7-10 P02-08=10 Position command + actual speed gain description
1053
1054 (2) Description of related parameters
1055
1056 |(% rowspan="2" style="width:68px" %)
1057 **P02-07**|(% style="width:150px" %)**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1058 |(% style="width:150px" %)The second gain switching mode|Operation setting|Effective immediately|0|0 to 1|Gain control|
1059 |(% colspan="8" %)(((
1060 Set the switching mode of the second gain.
1061
1062 |**Setting value**|**Function**
1063 |0|(((
1064 The first gain is used by default. Switching using DI function 10 (GAIN-SEL, gain switching):
1065
1066 DI logic invalid: PI control;
1067
1068 DI logic valid: PI control.
1069 )))
1070 |1|The first gain and the second gain are switched by the setting value of P02-08.
1071 )))
1072
1073 |(% rowspan="2" %)
1074 **P02-08**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1075 |Gain switching condition selection|Operation setting|Effective immediately|0|0 to 10|Gain control|
1076 |(% colspan="8" %)(((
1077 Set the conditions for gain switching.
1078
1079 |Setting value|Gain switching conditions|Details
1080 |0|The default is the first gain|Fixed use of the first gain
1081 |1|Switch by DI port|(((
1082 Use DI function 10 (GAIN-SEL, gain switching);
1083
1084 DI logic is invalid: the first gain (P02-01~~P02-03);
1085
1086 DI logic is valid: the second gain (P02-04~~P02-06).
1087 )))
1088 |2|Large torque command|(((
1089 In the previous first gain, when the absolute value of torque command is greater than (grade + hysteresis), the second gain is switched;
1090
1091 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.
1092
1093
1094 )))
1095 |3|Large actual torque|(((
1096 In the previous first gain, when the absolute value of actual torque is greater than ( grade + hysteresis ), the second gain is switched;
1097
1098 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 .
1099
1100
1101 )))
1102 |4|Large speed command|(((
1103 In the previous first gain, when the absolute value of speed command is greater than (grade + hysteresis), the second gain is switched;
1104
1105 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 .
1106
1107
1108 )))
1109 |5|Large actual speed|(((
1110 In the previous first gain, when the absolute value of actual speed is greater than (grade + hysteresis), the second gain is switched;
1111
1112 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 .
1113
1114
1115 )))
1116 |(((
1117
1118
1119 6
1120 )))|(((
1121
1122
1123 Large rate of change in speed command
1124 )))|(((
1125 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;
1126
1127 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 .
1128
1129
1130 )))
1131 |(((
1132
1133
1134 7
1135 )))|(((
1136
1137
1138 Large position deviation
1139 )))|(((
1140 In the previous first gain, when the absolute value of position deviation is greater than (grade + hysteresis), the second gain is switched;
1141
1142 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 .
1143 )))
1144 |8|Position command|(((
1145 In the previous first gain, if the position command is not 0, switch to the second gain;
1146
1147 In the previous second gain, if the position command is 0 and the duration is greater than [P02-13], the first gain is returned.
1148 )))
1149 |(((
1150
1151
1152 9
1153 )))|(((
1154
1155
1156 Positioning complete
1157 )))|(((
1158 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.
1159
1160
1161 )))
1162 |(((
1163
1164
1165 10
1166 )))|(((
1167
1168
1169 Position command + actual speed
1170 )))|(((
1171 In the previous first gain, if the position command is not 0, the second gain is switched;
1172
1173 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).
1174
1175
1176 )))
1177
1178
1179 )))
1180
1181 |(% rowspan="2" %)
1182 **P02-13**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1183 |Delay Time for Gain Switching|Operation setting|Effective immediately|20|0 to 10000|Gain control|0.1ms
1184 |(% colspan="8" %)(((
1185 The duration of the switching condition required for the second gain to switch back to the first gain.
1186
1187 [[image:image-20230515140953-9.png]]
1188
1189 **✎**Note: This parameter is only valid when the second gain is switched back to the first gain.
1190 )))
1191
1192 |(% rowspan="2" %)
1193 **P02-14**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1194 |Gain switching grade|Operation setting|Effective immediately|50|0 to 20000|Gain control|According to the switching conditions
1195 |(% colspan="8" %)(((
1196 Set the grade of the gain condition. The generation of the actual switching action is affected by the two conditions of grade and hysteresis.
1197
1198 [[image:image-20230515140953-10.png]]
1199 )))
1200
1201 |(% rowspan="2" %)
1202 **P02-15**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1203 |Gain switching hysteresis|Operation setting|Effective immediately|20|0 to 20000|Gain control|According to the switching conditions
1204 |(% colspan="8" %)(((
1205 Set the hysteresis to meet the gain switching condition.
1206
1207 [[image:image-20230515140953-11.png]]
1208 )))
1209
1210 |(% rowspan="2" %)
1211 **P02-16**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1212 |Position loop gain switching time|Operation setting|Effective immediately|30|0 to 10000|Gain control|0.1ms
1213 |(% colspan="8" %)(((
1214 Set the time for switching from the first position loop (P02-01) to the second position loop (P02-04) in the position control mode.
1215
1216 [[image:image-20230515140953-12.png]]
1217
1218 If P02-04≤P02-01, then P02-16 is invalid, and the second gain is switched from the first gain immediately.
1219 )))
1220
1221
1222
1223 = **Mechanical resonance suppression** =
1224
1225 == Mechanical resonance suppression methods ==
1226
1227 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.
1228
1229 **Torque instruction filter**
1230
1231 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:
1232
1233 (% style="text-align:center" %)
1234 [[image:image-20220706155820-5.jpeg||class="img-thumbnail"]]
1235
1236 **Notch filter**
1237
1238 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__.
1239
1240 == Notch filter ==
1241
1242 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.
1243
1244 **Width grade of notch filter**
1245
1246 The notch width grade is used to express the ratio of the notch width to the center frequency of the notch:
1247
1248 (% style="text-align:center" %)
1249 [[image:image-20220706155836-6.png||class="img-thumbnail"]]
1250
1251 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.
1252
1253 **Depth grade of notch filter**
1254
1255 The depth grade of notch filter represents the ratio relationship between input and output at center frequency.
1256
1257 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__.
1258
1259 (% style="text-align:center" %)
1260 (((
1261 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
1262 [[Figure 7-7 Notch characteristics, notch width, and notch depth>>image:image-20220608174259-3.png||id="Iimage-20220608174259-3.png"]]
1263 )))
1264
1265
1266 (% style="text-align:center" %)
1267 (((
1268 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
1269 [[Figure 7-8 Frequency characteristics of notch filter>>image:image-20220706160046-9.png||id="Iimage-20220706160046-9.png"]]
1270 )))
1271
1272
1273 (% class="table-bordered" %)
1274 |=(% 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;" %)(((
1275 **Setting method**
1276 )))|=(% style="text-align: center; vertical-align: middle; width: 121px;" %)(((
1277 **Effective time**
1278 )))|=(% 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**
1279 |=(% 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" %)(((
1280 Operation setting
1281 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1282 Effective immediately
1283 )))|(% 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
1284 |=(% 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" %)(((
1285 Operation setting
1286 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1287 Effective immediately
1288 )))|(% style="text-align:center; vertical-align:middle; width:99px" %)100|(% style="text-align:center; vertical-align:middle; width:102px" %)0 to 100|(% style="width:362px" %)(((
1289 1. 0: all truncated
1290 1. 100: all passed
1291 )))|(% style="text-align:center; vertical-align:middle; width:96px" %)-
1292 |=(% 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" %)(((
1293 Operation setting
1294 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1295 Effective immediately
1296 )))|(% 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" %)(((
1297 1. 0: 0.5 times the bandwidth
1298 1. 4: 1 times the bandwidth
1299 1. 8: 2 times the bandwidth
1300 1. 12: 4 times the bandwidth
1301 )))|(% style="text-align:center; vertical-align:middle; width:96px" %)-
1302 |=(% 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" %)(((
1303 Operation setting
1304 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1305 Effective immediately
1306 )))|(% 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
1307 |=(% 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" %)(((
1308 Operation setting
1309 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1310 Effective immediately
1311 )))|(% style="text-align:center; vertical-align:middle; width:99px" %)100|(% style="text-align:center; vertical-align:middle; width:102px" %)0 to 100|(% style="width:362px" %)(((
1312 1. 0: all truncated
1313 1. 100: all passed
1314 )))|(% style="text-align:center; vertical-align:middle; width:96px" %)-
1315 |=(% 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" %)(((
1316 Operation setting
1317 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1318 Effective immediately
1319 )))|(% 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" %)(((
1320 1. 0: 0.5 times the bandwidth
1321 1. 4: 1 times the bandwidth
1322 1. 8: 2 times the bandwidth
1323 1. 12: 4 times the bandwidth
1324 )))|(% style="text-align:center; vertical-align:middle; width:96px" %)-
1325
1326 Table 7-11 Notch filter function code parameters