三相电压型PWM整流器的改进控制策略的研究

首先从现有三相PWM整流器d-q模型出发，采用电网电压、d-q轴电流的前馈补偿技术，得到一种通用的矢量解耦控制策略．然后根据频域分析法，得出了整流器的一阶惯性模型，并推导出系统的频域控制模型．为了提高系统的动态性能，提出一种新型的负载电流前馈控制方案．该方案认为负载电流对系统而言是一个外部干扰信号，并根据控制系统的频域控制模型得出了对该干扰信号的最佳补偿，对其进行拉氏逆变换后整定为一单位脉冲函数，并将它加在d轴指令电流输出环节，大大提高了系统对指令电流的跟踪能力．最后仿直验证了该前馈控制方案的正确性。

Investigation of an Improved Control Strategy for Three-Phase PWM Voltage Rectifier

From the feedforward compensation technology of net voltage and d-q axis current, we got a general vector decoupling control strategy based on the present d-q model of three-phase PWM rectifier. Then, according to the frequency domain control method, we educed the rectifier's one-order inertia model and deduced the system's frequency domain control model. To improve the dynamic performance of the system, a new load-current feedforward control scheme was proposed. The scheme viewed the load current as an external interferential signal to the system and drew out the fittest compensation of the interference through the frequency domain model of the control system. The result was adjusted into a unit pulse function after an inverse L-transformation and was added to the d axis command current output node, which greatly boosted the system's tracking ability for the command current. Finally, the simulation verified the validity of the feedforward control scheme.