基于柔性多状态开关的配电网电压波动越限抑制方法

风电、光伏等可再生能源具有波动性和随机性,当其接入配电网时可能会造成配电网电压波动甚至越限。研究了含分布式电源的配电网电压越限问题的模型,以柔性多状态开关换流站示范工程为例,分析了柔性多状态开关的工作原理以及含柔性多状态开关的配电网对分布式电源的消纳能力。提出了在未知分布式电源出力和网络拓扑结构的情况下,采用由柔性多状态开关施加功率扰动的方法得到节点电压对有功功率和无功功率的灵敏度系数,进而调整流过柔性多状态开关各端口变流器的功率,使电压回到合理范围内。通过仿真验证了所提调控策略的有效性,解决了配电网电压波动越限的问题。

A Voltage Over-limit Suppression Method Based on Soft Normally-open Point in Distribution Network

Wind power, photovoltaic and other renewable energy sources are volatile and random. When they are connected to distribution network, they may cause voltage fluctuation or overtension. Taking station demonstration project of soft normally-open point(SNOP)as an example, the model of voltage over-limit problem of distribution network with distributed generators is studied. The working principle of SNOP and the acceptance capacity to distributed generators when SNOP is connected to distribution network are analyzed. On the condition that distributed power output and network topology are unknown, the sensitivity coefficient of the node voltage to active power and reactive power is obtained by applying the power disturbance of the SNOP, and then adjusting the power flow through the SNOP, which makes the node voltage return to a reasonable range. The effectiveness of the proposed control strategy is verified by simulation, and the problem of the voltage over-limit problem of the distribution network is solved.