抑制基于电压源型逆变器的三相独立微电网中的同步涌流

Synchronization of an incoming voltage source inverter (VSI) unit in a standalone micro-grid (SaMG) is complicated by the need for instantaneous voltage match between the inverter and its Point of Common Coupling (PCC). Violation of this requirement leads to undesirable inrush currents in- and possible tripping of- the incoming unit, which may even de-stabilize one or more units already operational in the micro-grid. Existing synchronization methods mainly focus on power sharing but provide little solution for the synchronization inrush problem. This paper proposes a current control technique using a feed-forward disturbance rejection loop to repeatably mitigate this inrush. It is analytically shown that the proposed control approach provides necessary damping to effectively reduce the synchronization inrush. Further analysis proves that retaining the feed-forward loop in the control system complicates the post-synchronization dynamics and, hence, it must be withdrawn post synchronization. The proposed strategy precludes any increase in sensor count. Extensive experimental results are presented to validate all analytical conclusions.