提高弱送端电网暂态电压稳定水平的调相机优化配置研究

新能源接入比例的不断提高导致送端电网的电压支撑能力下降,在常规电源小开机方式下易出现暂态电压稳定问题。以西北电网为例,揭示了典型新能源汇集送端电网暂态电压稳定问题,分析了调相机的优势和不同地点配置调相机对事故后电网暂态电压的影响效果。进一步结合预防与紧急控制,通过协调优化事故前调相机配置地点、容量和事故后的紧急控制,以系统安全性为约束,以控制代价最小为目标,提出了一种针对送端电压支撑薄弱电网的调相机优化配置方法。最后,通过实际典型电网进行了有效性验证。

Research on optimal allocation method of synchronous condensers for improving transient voltage stability level of weak sending-end power grid

The increasing proportion that renewable energy accessing to sending-end power grid leads to the decrease of voltage support capacity, and the problem of transient voltage instability is likely to occur when power grid operates in the mode of minimum generation. Based on Northwest grids as an example, it reveals the problem of transient voltage instability with the typical renewable energy sending-end power grid, and analyzes the advantages of the synchronous condenser and the effects with synchronous condenser locations on the transient voltage stability characteristics after the accident. And further combining prevention and emergency control, through coordinating and optimizing the configuration capacity and location of the synchronous condenser before the accident and the emergency control after the accident, it proposes an optimization configuration method of synchronous condenser for the weak voltage supporting sending-end power grid, which is based on security constraints and aims to minimize the control cost. Finally, the method is validated through the actual typical grid. This work is sponsored by National Key Research and Development Program of China (No. 2017YFB0902000) and Northwest Division of State Grid Corporation of China.