Distributed Secondary Control for Dynamic Microgrids for Seamless Topology Switching

Dynamic microgrids (MGs) with flexible and adjustable boundaries are supposed to facilitate the uninterrupted power supply from severe power outage. In this paper, an improved distributed secondary control for voltage and frequency regulation is proposed for seamless topology switching in dynamic MGs. Considering the topology of dynamic MGs is reconfigured to guarantee the power supply/demand balance, the transient fluctuation due to distribution generations (DGs) disconnection or reinjection is inevitable introduced. Therefore an auxiliary item is added to secondary control level to smooth the fluctuation before the connection or disconnection operation and to realize the proportional power sharing. Detailed control for dynamic multi-MGs is designed. The stability analysis is formulated through small signal dynamic model considering different operating conditions. The effectiveness of proposed strategy is verified with simulation cases based on MATLAB/Simulink.