基于改进混合法的电网运行可靠性评估方法研究

针对电网运行可靠性评估中难以计及系统的高阶故障状态影响、使用传统可靠性评估方法已经不能满足运行可靠性指标的计算时间要求等问题,提出一种解析法与蒙特卡洛法相结合的改进混合法,其基本思想是利用解析法处理系统的N-1阶故障,计算初始可靠性指标;对于系统的高阶故障以预想事故链替代,采用蒙特卡洛法抽样出连锁故障的初始环节,再进行中间环节的判断识别,并计算中间可靠性指标,累计计算系统的可靠性指标,实现系统的运行可靠性评估.通过对RTS-79算例和贵州某地区电网为例分析,并与传统的蒙特卡洛法对比系统是否考虑连锁故障的可靠性指标计算效果,验证了文中所提方法的正确性与有效性.

Research on Reliability Assessment Method of Power Grid Operation Based on Improved Hybrid Method

In view of the problem that the high-order fault state of the system is difficult to be considered in the reliability assessment of the grid operation, and the traditional reliability assessment method can not meet the calculation time requirements of the operational reliability index, an analytical method combined with the Monte Carlo method is proposed. The basic idea of the improved hybrid method is: firstly, the N-1 fault of the system is processed by the analytical method, and the initial reliability index is calculated; then, the high-order fault of the system is replaced by the expected accident chain, and the Monte Carlo method is used to sample the cascading fault. In the initial step, the intermediate link is judged and identified, and the intermediate reliability index is calculated. Finally, the reliability index of the system is calculated and the system operation reliability evaluation is realized. Through the analysis of RTS-79 system and a power grid in Guizhou Province, and comparing with the traditional Monte Carlo method, the correctness and validity of the proposed method are verified.