Research On Position Sensorless Control Of Permanent Magnet Linear Synchronous Motor Based On EKF

The traditional feeding system can not satisfy the need of high speed and precision machining increasingly. On the contrary, the direct feeding system of Permanent Magnet Linear Synchronous Motor (PMLSM) has the advantages in high speed, high precision, fast response and long journey, so it is widely applied in high speed and precision machining equipments. The direct feeding system of PMLSM leaves out the middle transfer motion equipments, so the system disturbance will put on the motor directly. Thus, the motor control system must have more stability and anti-jamming ability. The traditional control system generally have position sensor, which has many disadvantages. So researching for the position sensorless control system with excellent performance has been a research hotspot recently. The research theme of this dissertation is the position sensorless control system of PMLSM.This paper researched the position sensorless vector control of PMLSM, and set up the corresponding control system model. It systematically researched the pivotal position and speed estimating problem. Based on the analysis of various estimate algorithms, it presents a position and speed estimate algorithm based on EKF. Deduce the EKF algorithm from Kalman filtering in theory, simulate it in computer, and validate it in experiments. This paper proposes a initial position estimate method ofSurface-Mounted PMLSM------injecting voltage pulse vectors method, the estimateprecision of which can reach +0.9375°. By the EKF estimate algorithm and the injecting voltage pulse vectors method, the PMLSM can start up and run smoothly without any vibration or time delay.The hardware frame and software flow of EKF estimate system are designed in this paper. And it realized the position and speed estimating based on EKF. For measuring the phase voltage and phase current of motor, this paper expounds the principle of measuring circuit, design and make the Printed Circuit Boards, which are validated to be effective with experiments. This paper set forth the software development method of DSP, and developed the software which can realize the EKF estimate algorithm. The experiment results indicate that EKF estimate algorithm is feasible and its precision can satisfy the need of control system.