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该文研究共直流母线并联型风电变流器的环流问题.对于共直流母线并联变流器,采用载波移相技术后,由于变流器输出瞬时电压的差异,此时会产生不流经电机和电网,只在变流器之间流动的环流,因此,针对该情况,首先分析环流的特性,并根据分析结果设计基于PR控制的环流抑制策略,仿真与实验都验证了该策略的有效性.“,”This paper presents circulating current control strategies for a multi-megawatt direct-drive permanent-magnet wind power generator with parallel-operating converters linked by common dc bus.For multiple converters in parallel with a common dc bus,when carrier phase shifting parallel is used,the switching status of the converters in parallel will differ from each other.This creates currents that flow among power switching devices and will flows in a circular loop between the power converters and not affect the net current in either the generator or the power grid.In the paper,A circulating current model is derived and analyzed.The PR controllers are designed to suppress the circulating current.The simulation and experiment results of parallel full power converters show the feasibility of the proposed theory and control scheme.