UHV对接入区域高压配电网安全稳定的影响

采用EPRI-E'等值方法建立包含特高压和大中型城市高压配电网的多电压等级电网仿真模型,从特高压线路故障后退出、配电网内部线路和主要电源点N-1故障的时域仿真分析,研究了特高压投运后高压配电网稳定受到的影响,并定义最短路径确定受影响程度较大的区域.仿真结果表明,特高压线路发生故障后双线跳开,最短路径为5左右的220kV站点出线潮流变化较大,部分将过载或重载,可能诱发系统的连锁故障;配电网内部的故障如果是在特高压系统故障后发生,系统存在崩溃的风险.最后,针对特高压投运后系统的运行特征,提出了相应稳定控制的措施,确保电网安全稳定运行.

Influence of UHV on the Security and Stability of the High Voltage Distribution Network of Integration Area

EPRI-E' equivalent law was adopted to model the simulation system which includes ultra-high voltage system and high voltage distribution network. The influence on the security and stability of receiving-end grid with the operation of UHV was analyzed under three situations, including UHV fault, internal line fault and the main power plant fault of the distribution network. And then, this paper defined the shortest path to determine the affected area. The research has shown that, if double lines of UHV system jump after line fault, the flow of the outlets of 220 kV site with 5 of the shortest path becomes larger, and some lines will even overload and cascading failure may be caused. The risk of system collapse increases if the internal line or the main plant fault and UHV fault occur simultaneously. Finally, according to the operation characteristics of UHV, this paper proposed the corresponding stability control measures to ensure the normal operation of the power grid.