考虑电压暂降指标的电压协调控制方法研究

针对电压暂降给敏感负荷带来严重损失的问题,提出一种改进的紧急电压控制方法。通过STATCOM动态无功补偿和紧急切负荷控制策略协调补偿故障电压,改善电压暂降发生概率。首先,基于蒙特卡洛方法搭建故障模型,并计算电压暂降发生概率。接着,构建年总支出费用函数,优化求解费用最小所对应的STATCOM最优容量。进一步地,针对不同故障给节点造成不同的电压暂降深度,引进紧急切负荷控制。综合运用STATCOM补偿和切负荷控制手段,优先进行STATCOM补偿,但当STATCOM补偿容量达到上限时,进行紧急切负荷控制,最大限度抑制并降低电压暂降发生概率。最后,以广东东莞片区为例进行分析,仿真验证所提出方案的正确性和有效性。

Research on voltage coordination control method considering voltage sag index

Considering serious damage to sensitive load caused by the voltage sag, this paper proposes an improved emergency voltage control method. It installs STATCOM device and sheds load coordinately to compensate voltage to improve the voltage sag probability index. Firstly, based on the Monte Carlo method, fault model is built to calculate voltage sag occurrence probability. Then, the total annual cost function is put forward, which solves the minimum cost to get optimal capacity of the STATCOM. Further, according to different failures causing different failure severity to a node, an emergency load control is introduced. Combining the STATCOM with shedding load, the STATCOM is used to compensate voltage as the first priority. When the STATCOM compensation reaches its limit, it will shed the load to prevent and reduce the voltage sag occurrence probability as far as possible. Finally, an example of Dongguan district in Guangdong province is simulated, the results show that the method mentioned is correct and effective.