微电网分布式电源的分层控制策略研究

Hierarchical Control Strategy for Distributed Generation Microgrid

研究了分布式电源接入对微电网的影响,提出了微电网分布式电源的分层控制方法,实现了对微电网电压与功率的控制。根据微电网可以孤岛和并网运行的特性,采用两层控制方法。初级控制采用改进下垂控制方法,给出了基于电压外环、电流内环和功率环等的反馈控制器。二级控制通过初级控制信号重新控制逆变器的输出电压幅值和频率,使之重新达到平衡,能够实现系统运行的稳定。通过Matlab/simulink仿真,分析了微电网运行中各分布式电源的功率、电压和频率的变化规律,结果表明了微电网中分布式电源分层控制策略的有效性。

This paper studies the effect of the distributed generations connected to microgrid,proposes the corresponding control strategy. The hierarchical control method is proposed to control the voltage and power of the distributed generation microgrid. Besides,according to the characteristics of the microgrid of operation in islanding and connecting to the main grid,the two- level hierarchical control method is adopted. In this control method,the primary control adopts improved droop control method,providing feedback controller based on outer voltage loop,inner current loop and power loop etc. The secondary control uses the outputs of the primary control feeding back to control the inverter again,making these output signals balanced again and keeping the system stable. In order to verify the hierarchical control strategy in making the operation reliable,the simulation model of the micro- grid is built in Matlab / simulink. The simulation is implemented and analyzed different power modes of the distributed generations,as well as the frequency and voltage changing rules. The simulation results show that the microgrid hierarchical control strategy of distributed power is in good performance.