考虑分布式发电的配电网CPS可靠性评估

Reliability Assessment on Distribution Cyber Physical System Considering Distributed Generation

未来配电网将集成大量分布式发电(DG)和信息通信体系,但DG出力的不确定性和信息系统的不确定性会对电网安全可靠运行带来负面影响。提出一种考虑DG的配电网信息物理系统(CPS)可靠性评估方法。首先,面向故障后场景研究信息系统的支撑作用及其失效影响;然后,针对微网离网运行的过程,构建考虑信息系统影响的离网失效故障树模型;计及DG的不确定性,采用序贯蒙特卡洛方法模拟系统时序过程,并评估信息系统失效对配电网CPS的影响;最后,针对DG不同渗透率进行对比分析。算例结果验证了所提方法的有效性,可通过增大DG容量能改善系统可靠性。

Large-scale distributed generation （DG） and the corresponding information communication system will be integrated into the distribution grid in the future. However, the volatility of DG output and the uncertainties related to the cyber system will exert a negative impact on the safe and reliable operation of power grid. In this paper, a reliability assessment method for the distribution cyber physical system （CPS） is proposed considering DG. First, the support role of cyber system and the effect of its failure are analyzed in post-fauh scenarios, respectively. Then, a fault tree model is established for off-grid failure considering the influence of cyber system on the operation from the grid-connected mode to the islanded mode. Moreover, considering the volatility of DG output, the time-sequence process of CPS is simulated by means of sequential Monte Carlo method to evaluate the effect of eyber failure on the distribution CPS. Finally, comparative analysis is conducted at different penetration levels of DG. The results of a case study show the effectiveness of the proposed method, and it is suggested that the system reliability can be improved by increasing the DG capacity.