单相PWM整流器的输入电流H_∞重复控制方案

H_∞ repetitive control scheme for supply current of single-phase PWM rectifiers

针对单相PWM整流器的输入电流控制提出了H∞重复控制方案。通过引进一个虚拟扰动Δ(z)取代重复控制器的延迟环节z-Nd,重复控制器被很好地集成到H∞反馈控制器设计结构中,并能显著降低反馈控制器的阶数。详细地给出了H∞重复控制方案的设计方法。所提出的控制方案将H∞优化反馈控制与重复控制有机结合,并兼具二者的优点:动态响应快,鲁棒性好和跟踪稳态误差小。采用H∞重复控制方案控制的单相PWM整流器,不仅具有输入电流谐波含量低,稳态跟踪精确度高,动态响应快,而且在负载扰动发生的情况下,具有很好的鲁棒性。实验结果验证了所提控制方法的有效性。

A H∞ repetitive control scheme （HRC） was proposed to control supply current for single-phase PWM rectifiers. By the introduction of a virtual perturbation A （z） to replace delay link z-Nd, repetitive controller was well integrated to the design structure of H∞ feedback controller, and the orders of H∞ feed- back controller remarkably was reduced. The design procedure of H∞ repetitive control scheme was also presented in detail. The proposed control scheme which appropriately combines H∞ feedback control and repetitive control, inherits advantages from both sides： fast dynamic response, good robustness and high tracking accuracy. HRC controlled single-phase PWM rectifier not only produces high quality supply cur- rent with low total harmonic distortion, high tracking accuracy, and fast dynamic response; but also has good robustness under loads changes. Experimental results are provided to verify the effectiveness of the proposed control scheme.