高速列车牵引感应电机弱磁控制方法的研究

Study on Field-weakening Control of Induction Motor for High-speed Train

在高速列车中,牵引逆变器在弱磁区通常采用方波调制,电机定子电压的幅值仅取决于直流侧电压的大小而不能调节控制;而传统的矢量控制要求定子电压的幅值和相位均可控,方波工况下因电压幅值不能改变,电机的实际转矩并不能精确跟随给定转矩。本文提出了一种基于磁通补偿的弱磁控制策略,基于CRH2型动车组的实车参数及牵引特性曲线,借助理论分析和计算机仿真,与传统的弱磁控制进行比较,并在7.5KW电机平台上对所提方法进行实验验证;仿真和实验结果均表明,所提方法使得在方波工况下电机实际转矩仍能快速、精确地跟随给定转矩。

For high-speed train,the inverter usually operates in one-pulse PWM mode in the field-weakening area. The conventionalvector control requires controll ability of both the amplitude and the phase of the voltage for all time,so the actual output torque cannot follow the given torque. This paper will present a novel vector control strategy for induction motors in one-pulse PWM mode.The comparison with the conventional vector control based on the parameter of CRH2 also will be proposed by both theoretical analysis and computer simulation,and the strategy is aslo realized based on a 7.5KW experimental motor platform. The simulation resultand experimental result both shows that the actual output torque can follow the given torque exactly even in the one-pluse mode.