Bus-tie synchronization and load share technique in a ring bus system with multiple power inverters

A novel synchronizing technique is applied to a ring bus configured power system, with multiple solid-state inverters, to allow the bus-tie breaker to be closed at any time. After paralleling, load sharing is magnetically controlled without electronic circuitry or software control. Compared to the traditional one-at-a-time synchronization process, this approach significantly shortens the synchronization time as well as the interconnect-signal wire length, thus improving reliability and lowering the cost. This paper discusses the principles of this synchronization and load share control technique, supported by test results