Parallel PCS interconnection current surge elimination technique using coupled inductor

In this paper, coupled inductor method in parallel operation of PCS is proposed. In coupled inductor the primary and secondary currents flow in the same direction, the total flux total inductance is cancelled. However, when the currents flow in the opposite direction, each flux becomes an individual inductor. Aforementioned characteristic is adopted in parallel operation of PCS. Abnormal current is blocked by coupled inductor which is barred to connect grid code. A design guide is suggested by PCS´s capacity and the circulation current duration time. The proposed design is verified through the hardware implementation and experimental results that show the effectiveness of variance reduction.