A New V/f-Based Sensorless MTPA Control for IPMSM Drives

This paper presents a new closed-loop V/f control scheme for sensorless interior permanent-magnet synchronous motor drives. The proposed control scheme combines the merits of conventional V /f and field-oriented control strategies to achieve simple and high-performance motor drive. Two feedback stabilizing loops are designed to correct the V/f voltage vector reference and improve overall system stability. The voltage vector phase angle reference can rapidly be corrected instead of using indirect frequency modulation, which makes it more robust against transient disturbances. In addition, a maximum torque per ampere plug-in block is implemented to optimize torque generation efficiency without intensive power or power factor angle calculations. The proposed scheme is ideal for applications which require good control performance over the wide operating speed range. It also shows robustness to parameter variations caused by temperature increase or flux saturation. Theoretical analysis along with comparative simulation and experimental results are provided to validate the effectiveness of the proposed control scheme.