Research on the control strategy of PMSM under neutral point supply topology

This article proposes a novel neutral point supply topology for three-phase permanent magnet synchronous motor (PMSM) drive system, which integrates drive function and boost function in a single circuit. Firstly, a new coordinate transformation equation is derived, which leads to the mathematical model of the PMSM with neutral point. Secondly, the mathematical model of the neutral point supply topology is derived to analyze the operating principle of the equivalent DC/DC converter. Then, the control strategy of the system is subsequently designed. Finally, simulation is utilized to verify the correctness of the theoretical analysis and the effectiveness of the proposed control strategy. The simulation results show that the proposed system can maintain a stable step-up of the bus voltage, achieve accurate follow-up of the $dq$-axis currents, and output stable electromagnetic torque. The system provides a promising solution for high-efficiency and compact motor drive systems.