全数字化保护系统的主要问题及解决方案

分析了全数字化保护系统在可靠性方面存在的问题,提出利用元件重要度分析方法指导保护系统设计;分析了全网络化的保护系统在信息安全方面存在的隐患,提出在保证保护系统实时性和兼容性的前提下,基于IEC62351安全标准建设系统,并进行系统化的安全性评测;分析了全网同步、站内同步以及无同步对不同保护原理的影响,提出了不同原理的保护在失去同步后保护系统应采取的措施;比较了简单网络时间协议(SNTP)及IEEE1588 2种时间同步标准,提出应基于IEEE1588实现过程层的时间同步;分析了影响全数字化保护系统实时性的主要因素,提出利用光学互感器,利用GOOSE消息代替保护出口继电器以及利用交换式以太网技术等措施提高系统的实时性。

Main issues of all-digital protection system and solutions

The reliability issues of all-digital protection system are analyzed and the component importance analysis is introduced to guide protection system design.The information security issues of protection system on network are analyzed and it is suggested to set up protection system based on IEC 62351,with the precondition of ensured system speediness and compatibility,and systematically evaluate its security.The impacts of inter-substation synch,intra-substation synch and synch loss on different protection principles are analyzed respectively.Measures which should be taken during synch loss are proposed for protections based on different principles.Two synchronization standards of SNTP(Simple Network Time Protocol) and IEEE 1588 are compared and it is suggested to apply IEEE 1588 at process level.The main factors that affect the speediness of all-digital protection system are illustrated.It is suggested to adopt the optical transducer,the GOOSE message instead of output relay and the switching Ethernet technology to improve system speediness.