考虑储能SOC的微网接口变流器VSG协同控制

储能系统是微电网的重要组成部分,而保证储能系统的荷电状态(SOC)良好则是储能系统乃至整个微网安全高效运行的技术关键。文中提出了一种基于虚拟同步机(VSG)控制的交直流混合微网接口变流器与储能SOC协同控制策略,用以提高混合微网的频率、功率稳定性和系统内各储能SOC的分配合理性。首先对交直流微网两侧分布式电源的下垂控制方式及子网特性进行了分析,之后基于此特性提出了应用于接口变流器的VSG控制策略提高了系统频率功率稳定性,并且在功率分配环节中加入储能系统SOC控制策略,使各子网间储能SOC状态达到平衡,优化储能系统状态。最后利用Matlab/Simulink搭建了交直流混合微网模型对文中提出的算法进行了有效性验证。

VSG cooperative control of microgrid interface converter considering energy storage SOC

Energy storage system is an important part of micro-grid, and ensuring the SOC of energy storage system is the key to the safe and efficient operation of energy storage system and even the whole micro-grid. In this paper, a storage SOC coordinated control of AC/DC hybrid microgrid interface converter based on VSG control is designed, which can improve the frequency and power stability of hybrid microgrid and the rationality of each storage SOC in the system. Firstly, the droop control mode of distributed power supply on both sides of AC-DC microgrid and subnet characteristics are analyzed. Based on this characteristic, a VSG control strategy applied to interface converter is proposed to improve the frequency and power stability of the system. In the power sharing control block, the SOC control strategy of the energy storage system is added to control the interface converter to actively exchange power between subnets in order to optimize the SOC state of each storage system. Finally, an AC/DC hybrid microgrid model is built in Matlab/Simulink to verify the effectiveness of the proposed algorithm.