【摘要】 非隔离型柔性潮流转供装置因高频开关动作产生共模电压，在共模回路中产生共模电流。这不仅导致电能质量恶化，甚至引起保护误动，进而威胁配电系统的安全稳定运行。针对上述问题，提出一种面向三相四桥臂低压柔性潮流转供装置的共模电流主动抑制策略。建立变流器在三维空间矢量脉宽调制下平均共模电压与调制比的关系，通过调节冗余零矢量分配系数主动调节开关周期内的平均共模电压，实现共模电流的闭环抑制。此外，针对装置双端接入不同电压时仅单侧调节范围受限，导致共模电流难以抑制的局限性，提出一种双侧零矢量系数配合的协同控制方法，提升装置共模电流的调节范围与能力，并保证在单侧离网运行、并网电网电压波动等场景下装置共模电流得到有效抑制。更多还原

【Abstract】 The non-isolated flexible power flow transfer device can generate common-mode voltage due to high-frequency switching actions, which induces common-mode current in the common-mode circuit. It not only leads to the deterioration of power quality, but also causes maloperation of protection devices, thereby threatening the safe and stable operation of the distribution system. In allusion to the above problem, an active suppression strategy for common-mode current is proposed with three-phase four-leg low-voltage flexible power flow transfer device. The relationship between average common-mode voltage and modulation ratio under three-dimensional space vector pulse width modulation(3D-SVPWM) is established. By adjusting the distribution coefficient of redundant zero vectors to actively regulate the average common-mode voltage within the switching cycle, the closed-loop suppression of common-mode current is realized. In allusion to the limitation that when both ends of the device are connected to different voltages, only the adjustment range of one side is limited, making it difficult to suppress the common-mode current, a method of coordinated control with the cooperation of zero-vector coefficients on both sides is proposed. This method can improve the adjustment range and capability of the device’s common-mode current, and ensure that the common-mode current is effectively suppressed in scenarios such as single-side off-grid operation of the device and voltage fluctuations of the grid-connected power grid.更多还原