容错型牵引电机驱动系统的间接定子量控制

摘要

针对基于三相四开关容错逆变器的电力牵引传动系统，提出牵引电机的间接定子量控制方案。采用间接定子量算法生成参考电压矢量，以固定逆变器开关频率和减小电磁转矩脉动；通过含有饱和限幅环节的改进型磁链观测器抑制定子磁链的积分漂移。针对三相四开关空间电压矢量的特殊性，给出了容错逆变器SVPWM调制算法；考虑到容错逆变器直流侧电容中点电压不平衡的问题，建立了中点电压补偿模型，提出了一种基于PID调节器的补偿方案。通过MATLAB／Simulink仿真实验证明了所设计的基于三相四开关容错逆变器的牵引电机间接定子量控制方案的可行性和有效性。%An indirect stator⁃quantities control scheme of traction motor is proposed for the traction drive system based on three⁃phase four⁃switch fault⁃tolerant inverter. The indirect stator⁃quantities control algorithm is aodpted to generate the space voltage vectors for fixing switching frequency of the inverter and reducing electromagnetic torque ripple. An improved observer of stator flux containing saturation limiter is employed to restrain integral drift. The SVPWM algorithm of fault⁃tolerant inverter is given especially for three⁃phase four⁃switch space voltage vector. The neutral voltage compensation model of capacitors is established and a compensation scheme based on PID regulator is proposed for unbalanced neutral voltage on DC link of fault⁃tolerant inverter. MATLAB/Simulink simulation is carried out to verify the validity and effectiveness of the proposed control strategy.