交直流主动配电网多无功源协调的电压控制策略

Voltage Control Strategy Based on Coordinated Multiple Reactive Power Source in AC/DC Active Distribution Network

为解决分布式电源高渗透率的交直流主动配电网因分布式电源出力波动及负荷变化等造成的电压越限问题,提出了利用柔性直流装置、分布式电源及离散无功设备等多无功源构建的主动配电网电压控制策略。将配电网电压运行状态划分为3种:(1)正常状态下进行全局优化,通过离散无功设备的静态无功功率置换出柔性直流装置的动态无功功率,提高配电网动态无功储备容量;(2)预警状态下通过多无功源就地控制与集中控制相互协调,实现轻度电压越限节点的校正控制;(3)紧急状态下利用柔性直流装置对电压越限节点快速紧急支援,实现配电网过渡到预警状态或恢复到正常状态。利用IEEE 33节点系统进行了仿真和实验验证,仿真和实验结果表明该策略提高了系统的动态无功储备容量,实现了配电网电压的有效控制。

To solve the voltage deviation caused by the fluctuation of generation and variety of load in AC/DC active distribution network（ ADN） with distributed generation（ DG） of high-permeability,this paper proposes an ADN voltage control strategy composed of multiple reactive power source such as flexible DC device,DGs and discrete reactive power compensation equipment,etc. We divide the voltage running state of distribution network into three states.（ 1） In normal state,global optimization is conducted by putting into the discrete reactive power source and using its static reactive power to replace the dynamic reactive power of flexible DC device to improve the dynamic reactive power reserve capacity of distribution network.（ 2） In early warning state,the coordinated strategy of centralized control and local control is implemented through multiple reactive power source to adjust the node voltage which is slightly deviated.（ 3） In emergency state,the flexible DC device is used to rapidly support the deviating node and transform the state of distribution network into early warning state or normal state. The simulation and experimental validation based on IEEE 33-bus network are performed and the result shows that the proposed strategy can improve the reserve margin of the dynamic reactive power and realize the effective control of the distribution network voltage.