1. Center for Advanced Power-conversion Technology and Equipment, Southeast University, Nanjing 210096, China; 2. NARI Group Corporation(State Grid Electric Power Research Institute), Nanjing 211106, China; 3. NARI Technology Co., Ltd., Nanjing 211106, China
The medium- and low-voltage DC power distribution system consists of medium-voltage DC bus, low-voltage DC bus, DC transformer and so on, with the characteristics of multiple voltage levels, DC buses and converters. The operation modes and coordination control strategies of the system are more complicated. A medium- and low-voltage DC power distribution system is taken as the research object, and a decentralized unified control strategy based on the DC bus voltage signal is proposed. The photovoltaic power generation unit, energy storage unit and fuel cell unit on the DC bus adopt decentralized control strategies to adjust their working modes according to the DC bus voltage. The DC transformer utilizes a unified control strategy which integrates the functions of power control and the medium- and low-voltage DC bus voltage regulation. The DC transformer can automatically adjust the magnitude and direction of the transmission power based on normalized values of medium-voltage and low-voltage DC bus voltage deviations, and realize the global power sharing of the system. Finally, the simulation model of medium- and low-voltage DC power distribution system is built in MATLAB/Simulink, and simulation analysis of various operating states and scenarios is carried out to verify the effectiveness of the proposed control strategy.
PAN Pengpeng, CHEN Wu, HOU Kai,et al.Decentralized Unified Control Strategy for Medium- and Low-voltage DC Power Distribution System[J].Automation of Electric Power Systems,2019,43(23):72-80.DOI:10.7500/AEPS20190430005Copy