基于母线电压分层的直流微网系统协调控制

Coordinated Control of DC Microgrid System Based on Bus Voltage Stratification

在直流微网系统中,各分布式单元通常以分散的方式接入直流母线,而分布式电源和负荷易受到外界环境影响,从而影响直流微网母线电压稳定性。因此设计一种基于母线电压分层的直流微网系统协调控制策略,构建以光伏发电为主的直流微网系统结构,将母线电压划分为5个层级,针对不同层级对应的运行模式,研究分布式单元运行方式及其控制策略,最后通过仿真实验验证了所提控制策略在因环境因素变化导致光伏发电波动和负荷波动的情况下对抑制系统母线电压波动的有效性。

In a DC microgrid system,distributed units are usually connected to the DC bus in a decentralized manner,and distributed power sources and loads are easily affected by the external environment,which degrades the bus voltage stability of the DC microgrid.In order to solve this problem,a coordinated control strategy for DC microgrid system based on bus voltage stratification is proposed in this paper.The strategy builds a DC microgrid system structure mainly based on photovoltaic power generation,and then divides the bus voltage into five levels.Under the corresponding operation mode of each level,the operation mode and the control strategy are studied.Finally,the effectiveness of the proposed control strategy in suppressing the fluctuation of the system bus voltage is verified when the fluctuation of the photovoltaic power generation and the load is caused by the change of environmental factors.