Sensorless Control Of Modular Flux Switching Permanent Magnet Linear Motor

With the rapid development of economy, linear permanent-magnet motors, which can transform the electrical energy into linear motion directly. have got more and more applications. A complementary and modular linear flux-switching permanent magnet (CMLFSPM) motor is studied in this thesis, in which both the magnets and armature winding are placed in the short mover, while the long stator is made of iron core only. So this kind of motors will reduce the cost in the long stator applications. In order to achieve high-precision vector control of CMLFSPM motor, a linear grating encoder is needed which will increase the cost and motor volume and decrease the reliability. To resolve this kind of problem, a sensorless control of CLFSPM motor is studied in this thesis.The main contents of this paper are as follows:1. The background and significance of the research are described. The domestic and foreign research status of flux switching permanent magnet linear motor and its sensorless control algorithm are overviewed.2. The basic structure and working principle of CMLFSPM motor is introduced, and the mathematical model of the CMLFSPM motor is established in the three-phase stator stationary reference frame and two-phase rotating reference frame. The basic control strategies for CMLFSPM motors, including vector control, direct thrust control, hysteresis current control and space voltage vector control are discussed.3. The principle of the adaptive algorithm is briefly described, and the basic structure and working principle of the model reference adaptive system (MRAS) are presented in detail. Position sensorless control of modular linear flux-switching permanent magnet machine based on MRAS is developed, and the identification equation of speed and estimation error is derived as well.4. The mathematical model of CMLFSPM motor hysteresis loop control without position sensor based on MRAS and the model of CMLFSPM motor space voltage vector control without position sensor based on MRAS and the model of CMLFSPM motor are built respectively in MATLAB/Simulink.5. The hardware and software of CMLFSPM motor sensorless control drive system are designed. The hardware circuit of the system is described in detail. The part about software mainly introduces the main program flow and velocity displacement estimation program flow, speed PI controller program flow and displacement control program flow.6. An experimental platform for CMLFSPM motor sensorless control system is developed. And the CMLFSPM motor hysteresis loop control without position sensor based on MRAS and the CMLFSPM motor space voltage vector control without position sensor based on SVPWM are studied by using this platform, respectively. Experiment and simulation results show that the sensorless control of CMLFSPM motor based on MARS proposed in this thesis has good dynamic and static characteristics.7. The sensorless control of modular linear flux-switching permanent magnet machine based on MRAS application in the elevator door motor is presented. The performance of CMLFSPM motor for elevator and the operation requirement of the door machine system are introduced in this paper. In addition, the experimental results analyzed in detail.