An improved fuzzy system for position control of permanent magnet linear motor

In this paper, a fuzzy system with stable value is proposed to promote the traditional fuzzy controller and to be applied to position control of the permanent magnet linear motor. By a partition of error and change of error, the proposed fuzzy system can be used in a traditional fuzzy controller and can be switched to preceding a stable output control smoothly. For PMLM control system, the output of position control can be divided into a stable value and a changing one when the controlled system is close to stable state. A stable parameter value is acquired from the output of a traditional fuzzy controller when the controlled system comes into the stable state. And the stable parameter value can be tuned by a designed integral part so as to alleviate the static error. Simulation results show the improved fuzzy system has a higher performance than the traditional PID and the traditional fuzzy controller. The experiment results also verify that it has high precision in position control of PMLM.