Research on the Control Strategy of Permanent Magnet Synchronous Motors with Reduced Rotor Stack Length in Hybrid System

<div class="section abstract"><div class="htmlview paragraph">The key issue in the electromagnetic design of permanent magnet synchronous motors is the design of the rotor structure form of the motor. To achieve the goal of reducing the cost of the motor, this paper conducts electromagnetic design, optimal control calibration of the motor, and performance analysis for reducing the rotor lamination structure, and obtains the characteristics of the permanent magnet synchronous motor under this rotor structure. For the permanent magnet synchronous motor with reduced rotor stack length and one less motor temperature sensor, starting from vector control, the conditions for obtaining the maximum electromagnetic torque and the highest rotational speed are derived. Based on these conditions, the vector control strategies for the system operating under different working conditions are designed. At low speeds, the thermal loss of the stator winding is reduced with the maximum torque current ratio to improve the motor efficiency; as the rotational speed of the motor increases, when the mechanical angular velocity of the motor exceeds its turning point, the motor will enter the high-speed constant power zone. By increasing the field-weakening rotational speed to reduce the direct-axis current, the purpose of wide-range speed regulation is achieved. Through the analysis and experimental verification of the vector control strategy for the permanent magnet synchronous motor with reduced rotor stack length, the maximum electromagnetic torque, efficiency, field-weakening control rotational speed, harmonic injection control, motor current loop and rotational speed loop control are obtained, and the motor vector control platform is designed to ensure high motor efficiency. The test results show that the vector control strategy achieves the effect of reducing costs, rapid motor response, high energy efficiency, and wide speed regulation range.</div></div>