Minimum copper loss control for sensorless v/f controlled IPMSM drives

This paper presents a novel minimum copper loss control strategy for sensorless V/f controlled interior permanent magnet synchronous motor (IPMSM) drives. The proposed theoretical basis can be applied to both IPMSM and surface permanent magnet synchronous motor (SPMSM) drives to achieve high efficiency operation. Two control loops are used in the implementation that the active power information is used to generate a load angle compensation component to stabilize the drive and the reactive power is regulated to satisfy the constraint of the minimum copper loss in the steady state. In the reactive power regulation phase, it can properly generate a voltage amplitude compensation component to adjust the drive voltage such that the demanded minimum copper loss performance is obtained. Experimental results show that the demanded reactive power is well regulated in different load conditions and the DC link line current amplitude is reduced remarkably compared to a conventional control scheme. The proposed control strategy is successfully applied to a sensorless V/f controlled IPMSM drive and the performances have shown its effectiveness.