Risk analysis-a new aspect on protection and local control design

This report describes a novel aspect on protection and local control design. The new way to look at protection system design is to use risk analysis, to check how various designs will influence the dependability, security and availability. In the previous monopoly market, the main focus when designing protection and local control systems was on dependability. In a deregulated market, security becomes more important. For example, in Norway, the government will issue a new regulation in the year 2001, where the network companies will be economically penalised for not delivered energy. One of the main results of the risk analysis performed in this report is that a numerical single protection system has the highest security, and the same dependability as a redundant system. The increased availability due to the self-supervision in numerical equipment has a major impact on the result of the risk analysis