虚拟同步整流器并联系统功率分配方法

Power Distribution Method of Parallel System With Virtual Synchronous Rectifier

虚拟同步整流器技术可实现负荷侧变换器与电网的友好交互。为使并联系统中虚拟同步整流器能按额定容量输出功率,详细分析了直流电压采样偏差对功率均分的影响,提出一种基于有功电流反馈的功率均分策略。在此基础上,针对直流负载、有功-频率下垂、无功-电压下垂模式下的功率分配,给出了参数设计方法。其次,建立了双机并联系统的小信号模型,结合特征根轨迹分析了主要控制参数对系统稳定性的影响。最后,仿真和实验结果证明了所提方法的有效性。

Virtual synchronous rectifier technology can realize friendly interaction between load side converter and power grid.In order to make the virtual synchronous rectifier in parallel system output power according to rated capacity,the influence of DC voltage sampling deviation on power equalization is analyzed in detail,and a droop equalization control method based on active current feedback is proposed.Additionally,the parameter design method for DC load,active-frequency droop and reactive-voltage droop modes is given.Secondly,the small signal model of two-machine parallel system is established,and the influence of the main control parameters on the system stability is analyzed combining with the characteristic root locus.Finally,simulation and experimental results demonstrate the effectiveness of the proposed method.