Research on Motor Control and Application in Dual Motor Hybrid System

Abstract

<div class="section abstract"><div class="htmlview paragraph">This paper analyzes the current control, mode control and boost strategy of permanent magnet synchronous motor in dual hybrid system, which has good stability and robustness. Current control includes current vector control, MTPA control, flux weakening control, PI current control and SVPWM control. Motor mode includes initialization mode, normal mode, fault mode, active discharge mode, power off mode, battery heating mode and boost mode. The boost strategy of the hybrid system is based on boost mode management, boost target voltage determination and boost PI control. The specific content is as follows: Boost mode control. Boost mode includes initial mode, normal mode, off mode and fault mode. Boost target voltage is determined. Boost converter is controlled by variable voltage, which depends on the operation status of the motor and generator.. In order to improve the overall performance of the voltage control strategy, the voltage control strategy of the boost converter is dynamically adjusted by feeding the motor running state to the converter in real time, and the bus voltage is optimized. The motor application of the FOC strategy in the hybrid power system is the battery thermal control. The specific content is as follows: SVPWM control. SVPWM is based on the ideal flux loop of the three-phase symmetric motor stator powered by the three-phase symmetric sinusoidal wave as the reference standard, and the appropriate switching is carried out with different switching modes of the three-phase inverter, so as to form PWM waves and form actual flux vectors to track their accurate flux loops. Pulse thermal control. By applying the reactive voltage with high frequency changes and adopting the FOC control strategy, the inductive characteristics of the motor winding are constantly used to generate AC current on the bus. The high internal resistance of the battery at low temperature is used to constantly generate Joule heat on the battery. While avoiding the risk of lithium analysis on the battery, the battery itself will generate heat, thus increasing the temperature of the battery. Finally, the real vehicle test is carried out to verify the correctness of the motor control design.</div></div>