Direct torque and flux control of interior permanent magnet synchronous machine in deep flux-weakening region

Direct torque and flux control (DTFC) is known for its reduced torque and flux ripples compared to the classical direct torque control scheme. It can drive an interior permanent magnet synchronous motor (IPMSM) in usual control regimes while satisfying current and voltage limits of the system. However, deep flux-weakening control of an IPMSM under DTFC has not been investigated as extensively, especially operation along the maximum torque per voltage (MTPV) trajectory in the torque-flux plane. This study proposes a simple and effective control method, which incorporates MTPV trajectory in the conventional flux-weakening algorithm of DTFC. Performance of an IPMSM drive is analysed when operated with the proposed control method.