摘要
低频脉冲负载给电力系统的稳定运行带来巨大挑战。为改善电网电能质量、提升系统稳定性，本文针对带低频脉冲负载的三相交流电力系统，提出一种多功能补偿器（MFCs），具备同时补偿脉冲电流、谐波电流与无功电流功能。首先，对MFC的两种电路配置（即单级与两级结构）进行了全面的分析与对比评估。结果表明，单级结构在效率与简易性方面占优，而两级结构则能提供更优的补偿性能，并降低对解耦电容容值的需求。随后，详细阐述了MFC的工作机理、调制策略及控制系统设计。最后，研制了两款MFC实验样机进行测试，测试结果表明所提MFC可以消除低频脉冲电流冲击，THD从65%下降至10%以内，验证了所提拓扑与控制方法的有效性与可行性。
关键词： 低频脉冲；多功能补偿器；功率解耦；调制策略
Abstract
Low-frequency pulse loads pose significant challenges to the stable operation of power systems. To improve the quality of grid power and enhance system stability, Multi-functional compensators (MFCs), which possesses the capability to simultaneously compensate the pulse current, harmonic current, and reactive current, are proposed for three-phase AC power system with low frequency pulsed load. A comprehensive analysis and comparative evaluation of the circuit configuration for the MFC, including single-stage and two-stage solution, are presented. Single-stage MFC has the advantage of efficiency and system simplicity, while two-stage solution has better compensation effect and reduced decoupling capacitor requirement. Operation principle, modulation strategy and control scheme for the MFCs are analysed in detail. Prototypes of two MFCs are built and tested. The test results indicate that the proposed MFC can eliminate the impact of low-frequency pulse current, with THD decreasing from 65% to within 10%, thus verifying the effectiveness and feasibility of the proposed topology and control method.
Key words： Low frequency pulsed power; Multi-functional compensator; Power decoupling; Modulation strategy
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