H桥级联型多电平高压调速系统低速畸变补偿控制技术

H桥级联型多电平高压交流调速系统在低转速运行工况下,变频器处于低幅值调制比逆变状态,加之死区效应等非线性因素影响,导致变频器自身输出电压会出现严重畸变。针对这个问题,提出一种含定子电流畸变补偿的复合矢量控制技术,并详细介绍含畸变补偿矢量控制技术的设计原理与应用过程,包括转速变化情况下的电动机定子电流的谐波分量提取,以及畸变校正补偿的具体实现。同时,利用最小二乘法,推导出一种基于PID的时滞补偿器以改善系统响应输出特性。最后,在Matlab/Simulink中搭建仿真模型进行仿真研究,并在搭建的小型样机平台上进行试验验证,效果良好,仿真与试验结果证明了所提方法的有效性。

Distortion Compensation Control Designed for H-Bridge Cascade Multi-Level Converter under Low Speed Condition

Under low speed condition, the output voltage distortion of the cascade multilevel converter by low index modulation and dead-time is existed. In the paper, a novel vector control is presented to compensate the current distortion. A vector control scheme was put forward for asynchronous machine driven by a cascaded multi-level inverter to compensate dead-time effect of inverter and provide sinusoidal currents. The distortion causes and distortion component extraction method were analyzed in detail. Meanwhile, based on the least squares method, a PID time-delay compensator for enhancing the system response property is devised. Finally, the experimental test platform for the prototype is designed. The simulation results and experimental data show the effectiveness of the proposed algorithm.