Prescribed Performance Sliding Mode Controller for SVPWM Directly Driven PMSM

Permanent-magnet synchronous motors (PMSM) play important roles as actuators in various applications. Ideal control performance is achieved with field-oriented control (FOC) method based on space vector pulse width modulation (SVPWM). Howerver, an current inner-loop feedback control is not always utilized due to physical constraints, which asks for direct regulations of the phase voltages of the motors. Meanwhile, PMSMs have strong coupling and nonlinear characteristics, which asks for advanced control method such as sliding mode control (SMC). In this paper, the model of a SVPWM directly driven PMSM is firstly derived, then by substituting the traditional reaching law in SMC with a converted reaching law based on designed prescribed performance boundaries, prescribed performace sliding mode controller (PPSMC) is proposed and investigated. PPSMC is compared with proportional-integral (PI) controller and SMC through experiments. Results show that PPSMC shortens the sliding mode reaching period and improves motor's transient response compared to PI controller and SMC.