Abstract: The fuzzy PI control of the servo controller of permanent magnet synchronization motor （PMSM） was presented as a replacement of the traditional PI control to improve the controlling performance of PMSM．In this method‚ by detecting the rotor speed error and stator current error as well as their variation rate between the instant value and the referenced value‚the parameters P and I can be decided by looking up on-line empirical data‚thus realizing the servo control of PMSM．Simulation results prove that‚compared with the traditional PI control‚fuzzy PI control can effectively increase the response speed of the system‚reduce the torque pulses of the motor in both transient and stable states and improve the system stability.

Key words: permanent magnet synchronization motor, servo-driven system, fuzzy PI control