Efficient operation of deadbeat direct torque and flux control for IPMSM drives by minimizing copper losses

This paper presents copper loss minimization of an interior permanent magnet synchronous machine (IPMSM) drive using deadbeat direct torque and flux controller (DB-DTFC). With its constant switching frequency of DB-DTFC, the desired air-gap torque and stator flux can be achieved at the end of PWM sampling period. In this paper, a copper loss minimization DB-DTFC algorithm for an IPMSM is derived and demonstrated experimentally. Applying the presented DB-DTFC, the magnitude of stator flux linkage can be controlled while developing the commanded torque, such that copper losses of an IPMSM drive can be manipulated. The stator flux linkage that achieves minimum copper losses in an IPMSM over the given torque and speed operating space is presented. The effect of the proposed DB-DTFC algorithm is verified by analysing the efficiency maps of an IPMSM drive applying the copper loss minimizing stator flux linkage and a constant stator flux linkage.