For AC/DC hybrid microgrid with multi-bus structure

the realization of coordination control among multiple converters and smooth switching of different operation modes are the key points for microgrid control. Based on the Shangyu hybrid AC/DC microgrid demonstration project

this paper describes the structure design scheme and the converter control strategy of the microgrid. According to the state of interconnection switches

four typical AC/DC microgrid operation modes are designed

and twelve corresponding mode switching strategies and their implementation logic are described in detail

including planning and unplanned switching. Finally

the strategies are verified by actual operation results. The experimental results show that the proposed strategy can realize the function of power sharing

voltage/frequency recovery and seamless switching

and can improve the operational stability and the power supply reliability

while ensure the local consumption of distributed generation.