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Wiki source code of 07 Adjustments

Version 19.1 by Karen on 2023/05/15 14:10
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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 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 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:
348
349 (% style="text-align:center" %)
350 [[image:20230515-7.png]]
351
352 The usage method and conditions of model tracking control:
353
354 ~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.
355
356 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).
357
358 3. Set P2-20=1 to enable the function of model tracking control.
359
360 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.
361
362 5. After the responsiveness meets the requirements, user can adjust the parameters appropriately to increase the load rigidity level P3-2.
363
364 **✎Note**: Model tracking control is only available in position mode, and cannot be used in other modes.
365
366 |**Function code**|**Name**|(((
367 **Setting**
368
369 **method**
370 )))|(((
371 **Effective**
372
373 **time**
374 )))|**Default**|**Range**|**Definition**|**Unit**
375 |P2-20|Model tracking control function|Shutdown setting|(((
376 Effective
377
378 immediately
379 )))|0|0 to 1|When the function code is set to 1, enable the model tracking control function.|
380 |P2-21|Model tracking control gain|Shutdown setting|(((
381 Effective
382
383 immediately
384 )))|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
385 |P2-22|Model tracking control gain compensation|Shutdown setting|(((
386 Effective
387
388 immediately
389 )))|1000|500 to 2000|0.10%
390
391 |**Function code**|**Name**|(((
392 **Setting**
393
394 **method**
395 )))|(((
396 **Effective**
397
398 **time**
399 )))|**Default**|**Range**|**Definition**|**Unit**
400 |P2-23|Model tracking control forward rotation bias|(((
401 Operation
402
403 setting
404 )))|(((
405 Effective
406
407 immediately
408 )))|1000|0 to 10000|(% rowspan="2" %)Torque feedforward size in the positive and reverse direction under model tracking control|0.10%
409 |P2-24|Model tracking control reverses rotation bias|(((
410 Operation
411
412 setting
413 )))|(((
414 Effective
415
416 immediately
417 )))|1000|0 to 10000|0.10%
418 |P2-25|Model tracking control speed feedforward compensation|Operation setting|(((
419 Effective
420
421 immediately
422 )))|1000|0 to 10000|The size of the speed feedforward under model tracking control|0.10%
423
424 Please refer to the following for an example of the procedure of adjusting servo gain.
425
426 |**Step**|**Content**
427 |1|Please try to set the correct load inertia ratio parameter P3-1.
428 |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.
429 |3|Turn on the model tracking function, set P2-20 to 1.
430 |4|Increase the model tracking gain P2-21 within the range of no overshoot and vibration occur.
431 |5|If the rigidity level of step 2 is set relatively low, user can properly increase the rigidity level P3-2.
432 |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.
433
434 == **Gain switching** ==
435
436 Gain switching function:
437
438 ●Switch to a lower gain in the motor stationary (servo enabled)state to suppress vibration;
439
440 ●Switch to a higher gain in the motor stationary state to shorten the positioning time;
441
442 ●Switch to a higher gain in the motor running state to get better command tracking performance;
443
444 ●Switch different gain settings by external signals depending on the load connected.
445
446 (1) Gain switching parameter setting
447
448 ①When P02-07=0
449
450 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).
451
452 (% style="text-align:center" %)
453 [[image:20230515-8.png]]
454
455 ② When P02-07=1
456
457 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).
458
459 (% style="text-align:center" %)
460 [[image:20230515-9.png]]
461
462 Figure 7-9 Flow chart of gain switching when P02-07=1
463
464 |(% style="width:72px" %)**P02-08**|(% style="width:146px" %)**Content**|**Diagram**
465 |(% style="width:72px" %)0|(% style="width:146px" %)Fixed use of the first gain|~-~-
466 |(% style="width:72px" %)1|(% style="width:146px" %)Switching with DI|~-~-
467 |(% style="width:72px" %)(((
468
469
470
471
472
473
474 2
475 )))|(% style="width:146px" %)(((
476
477
478
479
480
481
482 Large torque command
483 )))|[[image:image-20230515140641-1.png]]
484 |(% style="width:72px" %)(((
485
486
487
488
489
490
491
492 3
493 )))|(% style="width:146px" %)Large actual torque|[[image:image-20230515140641-2.png]]
494 |(% style="width:72px" %)(((
495
496
497
498
499
500
501 4
502 )))|(% style="width:146px" %)(((
503
504
505
506
507
508
509 Large speed command
510 )))|[[image:image-20230515140641-3.png]]
511
512 |(% style="width:74px" %)**P02-08**|(% style="width:176px" %)**Content**|**Diagram**
513 |(% style="width:74px" %)(((
514
515
516
517
518
519 5
520 )))|(% style="width:176px" %)(((
521
522
523
524
525
526 Fast actual speed
527 )))|(((
528
529
530 [[image:image-20230515140641-4.png]]
531 )))
532 |(% style="width:74px" %)(((
533
534
535
536
537
538
539
540 6
541 )))|(% style="width:176px" %)(((
542
543
544
545
546
547
548
549 Speed command change rate is large
550 )))|[[image:image-20230515140641-5.png]]
551 |(% style="width:74px" %)(((
552
553
554
555
556
557
558 7
559
560
561 )))|(% style="width:176px" %)(((
562
563
564
565
566
567
568 Large position deviation
569 )))|[[image:image-20230515140641-6.png]]
570 |(% style="width:74px" %)(((
571
572
573
574
575
576 8
577 )))|(% style="width:176px" %)(((
578
579
580
581
582
583 Position command
584 )))|[[image:image-20230515140641-7.png]]
585
586 |(% style="width:73px" %)(((
587
588
589
590
591
592
593 9
594 )))|(% style="width:154px" %)(((
595
596
597
598
599
600
601 Positioning completed
602 )))|[[image:image-20230515140641-8.png]]
603 |(% style="width:73px" %)(((
604
605
606 10
607
608
609 )))|(% style="width:154px" %)(((
610
611
612 Position command + actual speed
613 )))|(((
614
615
616 Refer to the chart below
617 )))
618
619 (% style="text-align:center" %)
620 [[image:20230515-10.png]]
621
622 Figure 7-10 P02-08=10 Position command + actual speed gain description
623
624 (2) Description of related parameters
625
626 |(% rowspan="2" style="width:68px" %)
627 **P02-07**|(% style="width:150px" %)**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
628 |(% style="width:150px" %)The second gain switching mode|Operation setting|Effective immediately|0|0 to 1|Gain control|
629 |(% colspan="8" %)(((
630 Set the switching mode of the second gain.
631
632 |**Setting value**|**Function**
633 |0|(((
634 The first gain is used by default. Switching using DI function 10 (GAIN-SEL, gain switching):
635
636 DI logic invalid: PI control;
637
638 DI logic valid: PI control.
639 )))
640 |1|The first gain and the second gain are switched by the setting value of P02-08.
641 )))
642
643 |(% rowspan="2" %)
644 **P02-08**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
645 |Gain switching condition selection|Operation setting|Effective immediately|0|0 to 10|Gain control|
646 |(% colspan="8" %)(((
647 Set the conditions for gain switching.
648
649 |Setting value|Gain switching conditions|Details
650 |0|The default is the first gain|Fixed use of the first gain
651 |1|Switch by DI port|(((
652 Use DI function 10 (GAIN-SEL, gain switching);
653
654 DI logic is invalid: the first gain (P02-01~~P02-03);
655
656 DI logic is valid: the second gain (P02-04~~P02-06).
657 )))
658 |2|Large torque command|(((
659 In the previous first gain, when the absolute value of torque command is greater than (grade + hysteresis), the second gain is switched;
660
661 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.
662
663
664 )))
665 |3|Large actual torque|(((
666 In the previous first gain, when the absolute value of actual torque is greater than ( grade + hysteresis ), the second gain is switched;
667
668 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 .
669
670
671 )))
672 |4|Large speed command|(((
673 In the previous first gain, when the absolute value of speed command is greater than (grade + hysteresis), the second gain is switched;
674
675 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 .
676
677
678 )))
679 |5|Large actual speed|(((
680 In the previous first gain, when the absolute value of actual speed is greater than (grade + hysteresis), the second gain is switched;
681
682 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 .
683
684
685 )))
686 |(((
687
688
689 6
690 )))|(((
691
692
693 Large rate of change in speed command
694 )))|(((
695 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;
696
697 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 .
698
699
700 )))
701 |(((
702
703
704 7
705 )))|(((
706
707
708 Large position deviation
709 )))|(((
710 In the previous first gain, when the absolute value of position deviation is greater than (grade + hysteresis), the second gain is switched;
711
712 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 .
713 )))
714 |8|Position command|(((
715 In the previous first gain, if the position command is not 0, switch to the second gain;
716
717 In the previous second gain, if the position command is 0 and the duration is greater than [P02-13], the first gain is returned.
718 )))
719 |(((
720
721
722 9
723 )))|(((
724
725
726 Positioning complete
727 )))|(((
728 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.
729
730
731 )))
732 |(((
733
734
735 10
736 )))|(((
737
738
739 Position command + actual speed
740 )))|(((
741 In the previous first gain, if the position command is not 0, the second gain is switched;
742
743 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).
744
745
746 )))
747
748
749 )))
750
751 |(% rowspan="2" %)
752 **P02-13**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
753 |Delay Time for Gain Switching|Operation setting|Effective immediately|20|0 to 10000|Gain control|0.1ms
754 |(% colspan="8" %)(((
755 The duration of the switching condition required for the second gain to switch back to the first gain.
756
757 [[image:image-20230515140953-9.png]]
758
759 **✎**Note: This parameter is only valid when the second gain is switched back to the first gain.
760 )))
761
762 |(% rowspan="2" %)
763 **P02-14**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
764 |Gain switching grade|Operation setting|Effective immediately|50|0 to 20000|Gain control|According to the switching conditions
765 |(% colspan="8" %)(((
766 Set the grade of the gain condition. The generation of the actual switching action is affected by the two conditions of grade and hysteresis.
767
768 [[image:image-20230515140953-10.png]]
769 )))
770
771 |(% rowspan="2" %)
772 **P02-15**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
773 |Gain switching hysteresis|Operation setting|Effective immediately|20|0 to 20000|Gain control|According to the switching conditions
774 |(% colspan="8" %)(((
775 Set the hysteresis to meet the gain switching condition.
776
777 [[image:image-20230515140953-11.png]]
778 )))
779
780 |(% rowspan="2" %)
781 **P02-16**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
782 |Position loop gain switching time|Operation setting|Effective immediately|30|0 to 10000|Gain control|0.1ms
783 |(% colspan="8" %)(((
784 Set the time for switching from the first position loop (P02-01) to the second position loop (P02-04) in the position control mode.
785
786 [[image:image-20230515140953-12.png]]
787
788 If P02-04≤P02-01, then P02-16 is invalid, and the second gain is switched from the first gain immediately.
789 )))
790
791
792
793
794
795
796 == **Model Tracking Control Function** ==
797
798 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:
799
800 (% style="text-align:center" %)
801 [[image:20230515-7.png]]
802
803 The usage method and conditions of model tracking control:
804
805 ~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.
806
807 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).
808
809 3. Set P2-20=1 to enable the function of model tracking control.
810
811 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.
812
813 5. After the responsiveness meets the requirements, user can adjust the parameters appropriately to increase the load rigidity level P3-2.
814
815 **✎Note**: Model tracking control is only available in position mode, and cannot be used in other modes.
816
817 |**Function code**|**Name**|(((
818 **Setting**
819
820 **method**
821 )))|(((
822 **Effective**
823
824 **time**
825 )))|**Default**|**Range**|**Definition**|**Unit**
826 |P2-20|Model tracking control function|Shutdown setting|(((
827 Effective
828
829 immediately
830 )))|0|0 to 1|When the function code is set to 1, enable the model tracking control function.|
831 |P2-21|Model tracking control gain|Shutdown setting|(((
832 Effective
833
834 immediately
835 )))|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
836 |P2-22|Model tracking control gain compensation|Shutdown setting|(((
837 Effective
838
839 immediately
840 )))|1000|500 to 2000|0.10%
841
842 |**Function code**|**Name**|(((
843 **Setting**
844
845 **method**
846 )))|(((
847 **Effective**
848
849 **time**
850 )))|**Default**|**Range**|**Definition**|**Unit**
851 |P2-23|Model tracking control forward rotation bias|(((
852 Operation
853
854 setting
855 )))|(((
856 Effective
857
858 immediately
859 )))|1000|0 to 10000|(% rowspan="2" %)Torque feedforward size in the positive and reverse direction under model tracking control|0.10%
860 |P2-24|Model tracking control reverses rotation bias|(((
861 Operation
862
863 setting
864 )))|(((
865 Effective
866
867 immediately
868 )))|1000|0 to 10000|0.10%
869 |P2-25|Model tracking control speed feedforward compensation|Operation setting|(((
870 Effective
871
872 immediately
873 )))|1000|0 to 10000|The size of the speed feedforward under model tracking control|0.10%
874
875 Please refer to the following for an example of the procedure of adjusting servo gain.
876
877 |**Step**|**Content**
878 |1|Please try to set the correct load inertia ratio parameter P3-1.
879 |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.
880 |3|Turn on the model tracking function, set P2-20 to 1.
881 |4|Increase the model tracking gain P2-21 within the range of no overshoot and vibration occur.
882 |5|If the rigidity level of step 2 is set relatively low, user can properly increase the rigidity level P3-2.
883 |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.
884
885 == **Gain switching** ==
886
887 Gain switching function:
888
889 ●Switch to a lower gain in the motor stationary (servo enabled)state to suppress vibration;
890
891 ●Switch to a higher gain in the motor stationary state to shorten the positioning time;
892
893 ●Switch to a higher gain in the motor running state to get better command tracking performance;
894
895 ●Switch different gain settings by external signals depending on the load connected.
896
897 (1) Gain switching parameter setting
898
899 ①When P02-07=0
900
901 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).
902
903 (% style="text-align:center" %)
904 [[image:20230515-8.png]]
905
906 ② When P02-07=1
907
908 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).
909
910 (% style="text-align:center" %)
911 [[image:20230515-9.png]]
912
913 Figure 7-9 Flow chart of gain switching when P02-07=1
914
915 |(% style="width:72px" %)**P02-08**|(% style="width:146px" %)**Content**|**Diagram**
916 |(% style="width:72px" %)0|(% style="width:146px" %)Fixed use of the first gain|~-~-
917 |(% style="width:72px" %)1|(% style="width:146px" %)Switching with DI|~-~-
918 |(% style="width:72px" %)(((
919
920
921
922
923
924
925 2
926 )))|(% style="width:146px" %)(((
927
928
929
930
931
932
933 Large torque command
934 )))|[[image:image-20230515140641-1.png]]
935 |(% style="width:72px" %)(((
936
937
938
939
940
941
942
943 3
944 )))|(% style="width:146px" %)Large actual torque|[[image:image-20230515140641-2.png]]
945 |(% style="width:72px" %)(((
946
947
948
949
950
951
952 4
953 )))|(% style="width:146px" %)(((
954
955
956
957
958
959
960 Large speed command
961 )))|[[image:image-20230515140641-3.png]]
962
963 |(% style="width:74px" %)**P02-08**|(% style="width:176px" %)**Content**|**Diagram**
964 |(% style="width:74px" %)(((
965
966
967
968
969
970 5
971 )))|(% style="width:176px" %)(((
972
973
974
975
976
977 Fast actual speed
978 )))|(((
979
980
981 [[image:image-20230515140641-4.png]]
982 )))
983 |(% style="width:74px" %)(((
984
985
986
987
988
989
990
991 6
992 )))|(% style="width:176px" %)(((
993
994
995
996
997
998
999
1000 Speed command change rate is large
1001 )))|[[image:image-20230515140641-5.png]]
1002 |(% style="width:74px" %)(((
1003
1004
1005
1006
1007
1008
1009 7
1010
1011
1012 )))|(% style="width:176px" %)(((
1013
1014
1015
1016
1017
1018
1019 Large position deviation
1020 )))|[[image:image-20230515140641-6.png]]
1021 |(% style="width:74px" %)(((
1022
1023
1024
1025
1026
1027 8
1028 )))|(% style="width:176px" %)(((
1029
1030
1031
1032
1033
1034 Position command
1035 )))|[[image:image-20230515140641-7.png]]
1036
1037 |(% style="width:73px" %)(((
1038
1039
1040
1041
1042
1043
1044 9
1045 )))|(% style="width:154px" %)(((
1046
1047
1048
1049
1050
1051
1052 Positioning completed
1053 )))|[[image:image-20230515140641-8.png]]
1054 |(% style="width:73px" %)(((
1055
1056
1057 10
1058
1059
1060 )))|(% style="width:154px" %)(((
1061
1062
1063 Position command + actual speed
1064 )))|(((
1065
1066
1067 Refer to the chart below
1068 )))
1069
1070 (% style="text-align:center" %)
1071 [[image:20230515-10.png]]
1072
1073 Figure 7-10 P02-08=10 Position command + actual speed gain description
1074
1075 (2) Description of related parameters
1076
1077 |(% rowspan="2" style="width:68px" %)
1078 **P02-07**|(% style="width:150px" %)**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1079 |(% style="width:150px" %)The second gain switching mode|Operation setting|Effective immediately|0|0 to 1|Gain control|
1080 |(% colspan="8" %)(((
1081 Set the switching mode of the second gain.
1082
1083 |**Setting value**|**Function**
1084 |0|(((
1085 The first gain is used by default. Switching using DI function 10 (GAIN-SEL, gain switching):
1086
1087 DI logic invalid: PI control;
1088
1089 DI logic valid: PI control.
1090 )))
1091 |1|The first gain and the second gain are switched by the setting value of P02-08.
1092 )))
1093
1094 |(% rowspan="2" %)
1095 **P02-08**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1096 |Gain switching condition selection|Operation setting|Effective immediately|0|0 to 10|Gain control|
1097 |(% colspan="8" %)(((
1098 Set the conditions for gain switching.
1099
1100 |Setting value|Gain switching conditions|Details
1101 |0|The default is the first gain|Fixed use of the first gain
1102 |1|Switch by DI port|(((
1103 Use DI function 10 (GAIN-SEL, gain switching);
1104
1105 DI logic is invalid: the first gain (P02-01~~P02-03);
1106
1107 DI logic is valid: the second gain (P02-04~~P02-06).
1108 )))
1109 |2|Large torque command|(((
1110 In the previous first gain, when the absolute value of torque command is greater than (grade + hysteresis), the second gain is switched;
1111
1112 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.
1113
1114
1115 )))
1116 |3|Large actual torque|(((
1117 In the previous first gain, when the absolute value of actual torque is greater than ( grade + hysteresis ), the second gain is switched;
1118
1119 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 .
1120
1121
1122 )))
1123 |4|Large speed command|(((
1124 In the previous first gain, when the absolute value of speed command is greater than (grade + hysteresis), the second gain is switched;
1125
1126 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 .
1127
1128
1129 )))
1130 |5|Large actual speed|(((
1131 In the previous first gain, when the absolute value of actual speed is greater than (grade + hysteresis), the second gain is switched;
1132
1133 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 .
1134
1135
1136 )))
1137 |(((
1138
1139
1140 6
1141 )))|(((
1142
1143
1144 Large rate of change in speed command
1145 )))|(((
1146 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;
1147
1148 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 .
1149
1150
1151 )))
1152 |(((
1153
1154
1155 7
1156 )))|(((
1157
1158
1159 Large position deviation
1160 )))|(((
1161 In the previous first gain, when the absolute value of position deviation is greater than (grade + hysteresis), the second gain is switched;
1162
1163 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 .
1164 )))
1165 |8|Position command|(((
1166 In the previous first gain, if the position command is not 0, switch to the second gain;
1167
1168 In the previous second gain, if the position command is 0 and the duration is greater than [P02-13], the first gain is returned.
1169 )))
1170 |(((
1171
1172
1173 9
1174 )))|(((
1175
1176
1177 Positioning complete
1178 )))|(((
1179 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.
1180
1181
1182 )))
1183 |(((
1184
1185
1186 10
1187 )))|(((
1188
1189
1190 Position command + actual speed
1191 )))|(((
1192 In the previous first gain, if the position command is not 0, the second gain is switched;
1193
1194 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).
1195
1196
1197 )))
1198
1199
1200 )))
1201
1202 |(% rowspan="2" %)
1203 **P02-13**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1204 |Delay Time for Gain Switching|Operation setting|Effective immediately|20|0 to 10000|Gain control|0.1ms
1205 |(% colspan="8" %)(((
1206 The duration of the switching condition required for the second gain to switch back to the first gain.
1207
1208 [[image:image-20230515140953-9.png]]
1209
1210 **✎**Note: This parameter is only valid when the second gain is switched back to the first gain.
1211 )))
1212
1213 |(% rowspan="2" %)
1214 **P02-14**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1215 |Gain switching grade|Operation setting|Effective immediately|50|0 to 20000|Gain control|According to the switching conditions
1216 |(% colspan="8" %)(((
1217 Set the grade of the gain condition. The generation of the actual switching action is affected by the two conditions of grade and hysteresis.
1218
1219 [[image:image-20230515140953-10.png]]
1220 )))
1221
1222 |(% rowspan="2" %)
1223 **P02-15**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1224 |Gain switching hysteresis|Operation setting|Effective immediately|20|0 to 20000|Gain control|According to the switching conditions
1225 |(% colspan="8" %)(((
1226 Set the hysteresis to meet the gain switching condition.
1227
1228 [[image:image-20230515140953-11.png]]
1229 )))
1230
1231 |(% rowspan="2" %)
1232 **P02-16**|**Parameter name**|**Setting method**|**Effective time**|**Default**|**Set range**|**Application category**|**Unit**
1233 |Position loop gain switching time|Operation setting|Effective immediately|30|0 to 10000|Gain control|0.1ms
1234 |(% colspan="8" %)(((
1235 Set the time for switching from the first position loop (P02-01) to the second position loop (P02-04) in the position control mode.
1236
1237 [[image:image-20230515140953-12.png]]
1238
1239 If P02-04≤P02-01, then P02-16 is invalid, and the second gain is switched from the first gain immediately.
1240 )))
1241
1242
1243
1244
1245
1246 = **Mechanical resonance suppression** =
1247
1248 == Mechanical resonance suppression methods ==
1249
1250 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.
1251
1252 **Torque instruction filter**
1253
1254 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:
1255
1256 (% style="text-align:center" %)
1257 [[image:image-20220706155820-5.jpeg||class="img-thumbnail"]]
1258
1259 **Notch filter**
1260
1261 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__.
1262
1263 == Notch filter ==
1264
1265 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.
1266
1267 **Width grade of notch filter**
1268
1269 The notch width grade is used to express the ratio of the notch width to the center frequency of the notch:
1270
1271 (% style="text-align:center" %)
1272 [[image:image-20220706155836-6.png||class="img-thumbnail"]]
1273
1274 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.
1275
1276 **Depth grade of notch filter**
1277
1278 The depth grade of notch filter represents the ratio relationship between input and output at center frequency.
1279
1280 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__.
1281
1282 (% style="text-align:center" %)
1283 (((
1284 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
1285 [[Figure 7-7 Notch characteristics, notch width, and notch depth>>image:image-20220608174259-3.png||id="Iimage-20220608174259-3.png"]]
1286 )))
1287
1288
1289 (% style="text-align:center" %)
1290 (((
1291 (% class="wikigeneratedid img-thumbnail" style="display:inline-block" %)
1292 [[Figure 7-8 Frequency characteristics of notch filter>>image:image-20220706160046-9.png||id="Iimage-20220706160046-9.png"]]
1293 )))
1294
1295
1296 (% class="table-bordered" %)
1297 |=(% 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;" %)(((
1298 **Setting method**
1299 )))|=(% style="text-align: center; vertical-align: middle; width: 121px;" %)(((
1300 **Effective time**
1301 )))|=(% 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**
1302 |=(% 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" %)(((
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" %)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
1307 |=(% 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" %)(((
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;" %)P04-07|(% style="text-align:center; vertical-align:middle; width:155px" %)1st 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 |=(% 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" %)(((
1326 Operation setting
1327 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1328 Effective immediately
1329 )))|(% 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
1330 |=(% 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" %)(((
1331 Operation setting
1332 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1333 Effective immediately
1334 )))|(% 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" %)(((
1335 1. 0: all truncated
1336 1. 100: all passed
1337 )))|(% style="text-align:center; vertical-align:middle; width:96px" %)-
1338 |=(% 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" %)(((
1339 Operation setting
1340 )))|(% style="text-align:center; vertical-align:middle; width:121px" %)(((
1341 Effective immediately
1342 )))|(% 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" %)(((
1343 1. 0: 0.5 times the bandwidth
1344 1. 4: 1 times the bandwidth
1345 1. 8: 2 times the bandwidth
1346 1. 12: 4 times the bandwidth
1347 )))|(% style="text-align:center; vertical-align:middle; width:96px" %)-
1348
1349 Table 7-11 Notch filter function code parameters