Research On Key Technology Of Position Servo Control System For Interior Pmsm

With the proposal of “Made in China 2025” and “Industry 4.0”,the market demand for industrial robots is rising rapidly.Industrial robots are widely used in various fields because of their high integration,among which the motor servo drive system is one of the core components.The conventional id=0 control method of the hidden pole PMSM commonly used in the existing market has been unable to meet the application requirements of the manipulator.While the IPMSM has been widely used in the servo market because of its excellent performance brought by its structural characteristics.This paper focuses on how to improve the dynamic response and positioning accuracy of the IPMSM position servo control system.First of all,this paper aims at the condition that the manipulator’s joint needs low speed and high torque output on some specific occasions,and the interior property of the IPMSM itself causes the problem that the existing id=0 control causes the reluctance torque not to be fully utilized,the mathematical model of IPMSM is deduced,and the MTPA control based on IPMSM mathematical model is studied and analyzed.In order to make full use of the Interior property of IPMSM and meet the wide range speed regulation requirements of specific occasions,this paper proposes a flux weakening control method based on stator current lead angle to adjust the AC and DC axis current twice to realize a wide range of flux weakening speed regulation.In order to meet the needs of high-speed and the high-precision positioning of manipulator’s joints,this paper analyzes the three closed-loop servo control system of permanent magnet synchronous motor and finds that the existence of the intermediate speed loop of the traditional three closed-loop control has become a large inertia series delay link,which not only increases the order of the system and the difficulty of debugging but also limits the improvement space of positioning response speed.Therefore,this paper proposes a position speed integrated controller based on sliding mode control and designs a position current two-loop control system to improve the dynamic response and positioning accuracy of the system.Secondly,in order to verify the effectiveness of the proposed method,the proposed algorithm is verified by MATLAB/SIMULINK.Firstly,the comparison test between the maximum torque current ratio control and id=0 control is carried out.The simulation results show that the maximum torque current is faster than the motor under the control system to respond to the speed and the stator current is smaller,which can effectively improve the utilization rate of stator current,reduce copper consumption and improve the operation efficiency of IPMSM constant torque area.Then,the performance test of the weak magnetic control is carried out.The simulation results show that the IPMSM has a wider speed regulation range under the function of the weak magnetic control module.Finally,the performance comparison test between the two-loop system and the traditional three-loop system is carried out.The simulation results show that the two-loop system can effectively improve the response speed and positioning accuracy of the system.Finally,the software and hardware of the AC servo drive system are developed,and the test platform is built to test and analyze the performance of the system.The experimental results show that the maximum torque current control scheme based on IPMSM mathematical model can achieve the given value of speed faster than the id=0control scheme,and has a faster dynamic response.At the same time,the flux weakening control based on stator current lead angle can make the motor get twice the speed range.Compared with the traditional position speed current three-loop control system,the proposed position speed integrated two-loop control system has higher positioning accuracy and faster positioning response speed.Therefore,the AC servo control system proposed in this paper has the advantages of low speed and high torque starting performance,wider speed range,and high-speed,which is more suitable for industrial robot driving.