含多种分布式电源的微电网控制系统研究

Research on Microgrid Control System with Different DG Types

针对微网的并网与离网运行方式以及两种运行方式之间的转换,提出一种含多种新能源分布式电源的微网控制策略,建立控制系统。采用直流与交流微电网混合方式对交流负荷供电,在交流侧,采用独立的公共DC/AC变换,连接到一条微网母线上。针对微网的并网运行模式,建立P/Q控制模型,离网运行模式采用V/f控制方法。采用风力发电、光伏发电、蓄电池储能3种微源作为组网单元,对3种微源进行并/离网切换及负荷切断/闭合运行控制,建立微电网系统仿真,初步验证系统可行性。

According to the grid-connected and islanded operating modes of microgrid and the changeover between them,a control strategy of mierogrid with different kinds of DG （distributed generation） was proposed,which monitors the operating states of both microgrid and power network and provides the unified coordinating control by the central controller of microgrid. DC micro-grid and AC micro-grid hybrid was adopted. An independent public DC/AC converter used in AC side. Not only the load demand was satisfied, but also the converter resources were saved. P/Q control model was established based on grid-connected model. And in isolated mode, the converter was working in V/f control. The direct-drive permanent magnet wind power generation system, dual-stage PV generation system and Li-ion battery energy storage system were used as networking unit, and the results of transferring microgrid operation, modes and cutting or increasing load in islanded mode show the effectiveness and feasibility of the proposed control strategies.