Maximum Voltage Utilization of IPMSMs Using Modulating Voltage Scalability for Automotive Applications

A hybrid maximum voltage utilization controller is developed for interior permanent-magnet synchronous motors over a wide operating range. The structure of the controller combines the current vector control (CVC)-type maximum torque per ampere controller and the modulating voltage-scaled controller (MVSC). The hybrid structure provides a smooth transition from the CVC to the proposed MVSC mode by deactivating the current regulator in the flux weakening region. A seamless transition to a full six-step modulation can be realized by adjusting the scaling gain, which is a significant merit in terms of power utilization for wide flux weakening applications. This paper also examines the torque control accuracy under motor parameter drifts to determine how to decouple its effect using a voltage disturbance state-filter design.