基于MCMC方法的二次系统风险评估研究

Research on secondary system risk assessment based on MCMC methods

据统计,电力系统的大面积停电事故中,有70%以上都与二次系统有着直接或间接的关系,因此一个高可靠二次系统对建立坚强、健康的电网有着至关重要的作用。从二次系统的风险程度对电力系统可靠性的影响入手,应用MCMC方法进行研究,提出了系统的四个可靠性指标作为二次系统风险大小的衡量标准。MCMC方法继承了传统MC方法的优点,且有着收敛速度快、计算结果精确、指标稳定的特点,并实现动态模拟。通过IEEE-RTS 24节点的算例仿真,说明了MCMC方法的有效性和稳定性。最后以贵州地区某电网为算例,研究该地区四种典型运行方式下的可靠性指标,结果表明在冬大的运行方式下二次系统的风险程度更大,这对于建立更加可靠安全的电力系统来说有一定的参考价值。

According to the statistics,there are more than 70% of the accidents are linked to the secondary system directly or indirectly among large area blackouts in power system. So the high reliability of the secondary system is vital to the establishment of a strong and health grid. Considering the risk of secondary system affects the reliability of the power system,this paper makes a research with application of the MCMC method and puts forward 4 reliability indices of the grid as the measurement standard of the secondary system risk. The MCMC method inherits the advantages of traditional MC method,which has a fast convergence speed,accurate calculation and stable index,as well as realizes dynamic simulation. Through the simulation of IEEE-RTS 24 nodes,this paper illustrates the validity and stability of the MCMC method. Finally,taking a Guizhou local grid as an example,this paper calculates 4 reliability indices under 4 typical operation modes. The results show that the secondary system risk is larger in winter operation mode,which has great reference value for establishing a more reliable and security power system.