Space Decoupling Sensorless Control of Five-Phase Flux-Intensifying PM Motor Based on AFCCF-SMO Considering Flux-Weakening Operation

Abstract

Under the flux-weakening (FW) operation, the sensorless control of a five-phase flux-intensifying permanent magnet (FP-FIPM) motor faces the dilemma of reduced torque output and poor estimated accuracy caused by the serious space coupling between sensorless control and FW control. To overcome the abovementioned problems, a novel space decoupling sensorless control strategy for the FP-FIPM motor under FW operation is proposed in this article. Based on the decoupling model of the FP-FIPM motor, this article first proposes the dual space design to achieve the decoupling of sensorless control and FW control. For the FW control, an adaptive third-harmonic current injection strategy is proposed based on the fundamental space, which can effectively improve the torque output capability of the FP-FIPM motor. For the sensorless control, an adaptive frequency complex coefficient filter sliding mode observer (AFCCF-SMO) is developed based on the third-harmonic space, which can reduce complex disturbances and further improve the estimated rotor position accuracy. The feasibility of the proposed strategy is verified by experimental results.