【摘要】 电子电力变压器(EPT)采用并联运行方式,可以提高电网供电的可靠性。在并联过程中下垂控制策略应用最为广泛。传统的下垂控制在线路阻抗不相等时会导致负荷分配不均并产生环流。为解决这一问题,提出了一种自适应下垂控制策略,将并联运行的EPT输出级功率的一次函数变成P、Q的二次函数,根据各自的额定容量求出对应的功率比例,调节实际输出功率,使EPT按额定容量成正比分配负荷,减小了线路阻抗不均造成的影响。在Matlab/Simulink中搭建仿真模型,并联系统动态性能良好,仿真结果验证了所提出控制策略的有效性和可行性。更多还原

【Abstract】 The parallel operation of electronic power transformers(EPTs)can improve the reliability of power supplyfrom power grid,in which the droop control strategy is most widely used. When the line impedance is unequal,the tra-ditional droop control strategies will cause uneven load distribution and circulation. To solve this problem,an adaptivedroop control strategy is proposed,under which the linear function of each output power from the EPT in the parallel op-eration process is transformed into a quadratic function with respect to P and Q;the corresponding power ratio is calcu-lated according to the rated capacity of each EPT,respectively;the actual output power of EPTs is adjusted to shareload in proportion to the rated capacity,thus reducing the impact of uneven line impedance. A simulation model is builtbased on Matlab/Simulink. The parallel system has a satisfying dynamic performance,and simulation results verify theeffectiveness and feasibility of the proposed control strategy.更多还原