基于信息可达性的智能变电站继电保护系统风险评估方法

Risk Assessment for Protection System in Smart Substation Considering Information Reachability

借助于有效的状态监测和故障诊断技术,智能变电站继电保护系统的各类故障可观,然而对于故障的风险尚缺乏有效的定量评估手段。构建智能变电站继电保护系统的网络拓扑,从信息在网络拓扑中传输的角度,用改进简化的可达矩阵算法分析信息在源宿之间的可达性。通过构建继电保护系统失效树,定性分析故障引起的不可达信息,判别其风险类型。最后综合考虑一次间隔重要度和继电保护故障严重度评估故障的风险。算例结果表明所提方法能有效分析继电保护故障带来的风险影响,并能合理区分不同故障的风险影响大小,验证了所提方法的有效性和必要性。

With high-speed information sharing and state monitoring technologies, faults of protection system in smart substation can be totally observed. However, there are limited effective methods that can be implemented to evaluate the risk of protection system faults. This paper illustrates the network topology model of protection system in smart substation, where the information transmits between devices. An optimized simple information reachability analysis algorithm is proposed to analyze whether information can reach its destination from source. Furthermore, a failure analysis tree of protection system is built to deduce risk types caused by the unreachable information. Lastly, a risk assessment method is proposed, taking importance of power equipment and risk type of secondary faults into consideration. Case study shows that the proposed algorithm and method can efficiently distinguish different faults and evaluate their risks. Therefore effectiveness and necessity of the proposed algorithm and method is verified.