Unit power factor control of PMSM fed by indirect matrix converter

Low voltage transfer ratio is a main drawback of indirect matrix converter (IMC) for PMSM drive applications. This situation can be improved by unit power factor control of PMSM. According to the circuit equations of PMSM, this paper analysis the relationship between the amplitude of terminal voltage, so the terminal reactive power, and d-axis stator current. Based on the rotor field oriented vector control strategy of PMSM and space vector modulation algorithm of IMC, a novel unit power factor control method is proposed. In this method, a controller is employed to regulate the terminal reactive power and generate the reference value of d-axis current. Hence, the actual d-axis current is automatically adjusted to realize unit power factor operation of PMSM. The proposed method doesn´t need accurate motor parameters and thus is robust. The validity and feasibility of the proposed strategy is verified by experiments carried out on a 2.4 kW IMC-PMSM prototype.