Advanced induction motor drive control with single current sensor

Abstract

This paper proposes an induction motor drive control method which uses a minimal number of sensors, providing only DC-link current as a feedback signal. The improved DC-link current sampling scheme and modified asymmetrical switching pattern cancel the characteristic waveform errors which exist in all three reconstructed motor line-currents. Motor line-current harmonic content is reduced to an acceptable level, eliminating torque and speed oscillations which were inherent for conventional single sensor drives. Consequently, the use of sin-gle current sensor and line-current reconstruction technique is no longer ac-ceptable only for low and medium performance drives, but also for the drives where obtaining a highly accurate, stable, and fast response is the priority. The proposed control algorithm is validated using induction motor drive hardware prototype based on TMS320F2812 digital signal processor.