Research On Condiction-based Maintenance And State Evaluation Of Relay Protection

As the electrical power system develops, the power net is getting more and more complex, as well as the work load and cost of the maintenance. For a long time, the maintain strategy of our power system equipments is cycled recondition, but as the relay protection getting used more widely than ever, the cycled recondition shows its drawbacks. With the relay protection’s self-checking abilities getting more and more advanced, the normal cycled recondition is not enough for the current situation, we have to take the relay protection’s realtime running status into consideration. This paper focus on the following points:Firstly, this paper introduced the current recondition status of relay protection, put forward some existing problems, analyzed the reasons of relay protection malfunction.Secondly, this paper had a further discussion about the use of online monitoring and fault diagnosis technology in the state maintenance of relay protection. Based on the research of reliability technology of power equipments, those equipments of higher chance of malfunction should be applied with online monitoring technology. This paper also concluded the current existing problem of using online monitoring technology, and put forward the way of using online monitoring technology in relay protection, discussed about the fault diagnosis expert system, which is of the most importance in state maintenance of relay protection.Thirdly, based on the principle of relay protection and its realtime running status, the paper analyzed the relay protection status evaluation parameters and indicators, established the relay protection status evaluation index system and evaluation model, introduced using the analytic hierarchy process to calculate the model’s various state parameters weight and thus showed the influence level to relay protection’s status.Then, this paper emphasized on the daily use status of PMS system, put forward a way to evaluate the relay protection status by using the realtime and accurate basic data of PMS system.Lastly, in order to provide the state maintenance of relay protection with a comprehensive guide, the author himself combined with the current requirements of Zhejiang state grid company, introduced how to make the maintenance strategy, the test projects and relay protection first seizure type approval.