Current regulation for surface permanent magnet synchronous motor drives using integrated current sensors in the low-side switches

A new synchronous-frame current regulator configuration for surface PM machine is presented that utilizes incomplete phase current measurements from integrated pilot current sensors to deliver attractive regulator performance. Since pilot current sensors are directly integrated into the power switching devices, they provide opportunities to reduce the cost, size, and weight of three-phase inverters by eliminating dedicated current sensors in motor drive applications. However, a three-phase inverter equipped with these sensors in the three low-side switches cannot measure the complete load current waveforms, requiring the development of this new current regulator algorithm. An auto-tuning method is described that significantly reduces the sensitivity of the regulator to errors in the estimated machine parameters. Experimental results are provided to verify the appealing performance characteristics of the proposed regulator.