# Simulink simulates the vector control (FOC) of permanent magnet synchronous motor and starts the oscillation problem

2022-02-02 22:48:05

stay simulink A permanent magnet synchronous motor is built in the FOC simulation model PI The parameters are ： Speed ring P=0.273 I=567.7
q Shaft current P=100 I=0.2
d Shaft current P=600 I=0.65
Motor parameters are Speed input constant 120, The load torque is 0.05 Step signal input at seconds , The magnitude is 0.1
The result The start-up phase oscillates violently , I would like to ask you why ？

Refer to the answer 1：

There is no specific calculation , Mainly a process suggestion ,
1、 Check the performance of current loop . Disconnect the speed ring , Only keep dq Shaft current ring , And the output of the motor module Te Connect directly to Tm, Construct a locked rotor condition . Then give a id and iq, Observe whether giving and feedback can follow . If the following performance of feedback is good , The speed is also good , Then there is no problem with the current loop . If the current loop cannot follow , Recalculate the current loop PI Parameters , And re debug , Debug the speed ring after ensuring the performance of the current ring is intact .
2、 Check the performance of the speed ring . Close the speed ring , First, pay attention to check several points , The first is whether the feedback unit is consistent with the given unit , The output of the motor module is the mechanical speed and the unit is rad/s, multiply 9.55 after rpm; The second no-load commissioning , First eliminate the starting problem caused by load ; Third, check whether the given speed exceeds the rated speed of the motor , Double closed loop FOC It is impossible to follow beyond the rated speed , Fourth, check whether the limiting amplitude is set reasonably , The motor rated current limit amplitude can be preliminarily set . There is no problem in confirming , It is recommended to give a command speed of one-half of the rated speed , Then observe the following effect . If you follow , Of course, it's no problem , If there is static error between given and feedback , be PI Parameters need to be optimized , How to adjust the specific PI Yes, Baidu. , A lot of . But if there is a shock problem , prove PI The basic error is not in one order of magnitude , The effect of debugging is limited , It is recommended to recheck whether it is PI Parameter calculation error .
3、 Another suggestion is to simulate in this discrete environment , More in line with the actual working conditions .

Refer to the answer 2：