Comparison of efficiency for a PI and a FLC based IPMSM drive incorporating loss minimization algorithm over wide speed range

This paper presents a comparison in efficiency between a fuzzy logic controller (FLC) and a proportional-integral (PI) controller based interior permanent magnet synchronous motor (IPMSM) drive incorporating an online loss minimization algorithm (LMA). The LMA is developed based on the motor model. In order to maximize the operating efficiency the d-axis armature current is controlled optimally based on the developed LMA. A novel fuzzy logic controller (FLC) is developed, in such a way that it can simultaneously control both torque and flux of the motor while maintaining current and voltage constraints. Thus, the FLC extends the operating speed limits for the motor. The LMA is incorporated with the FLC so that the motor can operate over a wide speed range while maintaining the high efficiency. A performance comparison of the LMA based IPMSM drive with FLC and PI controller is provided. Simulation results demonstrate the higher efficiency and better dynamic response of the FLC based drive as compared to the PI controller over a wide speed range. The complete drive is also experimentally implemented using DSP board DS1104 although the complete experimental tests are yet to be done.