Research Of Direct Thrust Force Control System Of Linear Motor Based On DSP

This dissertation is devoted to the study on permanent magnet synchronous linear motor (PMSLM) in direct torque control (DTC) supported by National Science Foundation (No: 50375102). A lot of works were studied in direct torque technology and control strategy.Direct torque control is a kind of new technique, which has been developed in the middle of 1980s. It has been paid widely attention for its novel special controlled strategy, concise system structure, excellent dynamic and static performance. It has been successfully applied to many occasions up to now. This paper applied direct torque control to permanent magnet synchronous linear motor and named this technique direct thrust force control (DTFC).Permanent magnet synchronous linear motor was taken as an example in this dissertation. Direct thrust force control is investigated thoroughly and a primary flux oriented control of the PMSLM based on the voltage space vector pulse width modulates is presented to decrease the thrust ripple. The author introduced the designed method about this control strategy, including space vector choosing and modulating. It can realize the approximate continuous space vectors and improve the performance of the motor. On the basis of the mathematical model of PMSLM, the author designed a simulation-system of DTFC . Results of simulating indicated that better system performance could be derived from the control strategy under the same condition comparing with the traditional method.To improve the efficiency of the motor, the amplitude of flux linkage is varied accrding to the load of the system. Compared with constant flux linkage, exciting current is minished with light load. Results of simulating indicate the validity of the variable flux linkage strategy.A high performance full digital motor servo system based on the TMS320LF2407 has been developed. The results of the DTFC experiment on the system are obtained at last.