Research And Design Of The Condition Maintenance System Of Relay Protection Equipment

With the rapid transformation of our country’s power gird scale and power system planning and the digital and intelligent degree of electrical equipment’s gradual increasing,the secondary system’s situation restrain the safe and stable operation of the power system.Relay protection,which can guarantee the power system’s safety and stability has long been regarded as the most effective approach.Keep the relay protection in a good state is every power practitioner’s most important work.At present,still using traditional maintenance method can no longer guarantee the fault free operation of the device.The old method is no longer applicable at all.Changing the maintenance method right now is the most necessary job.Put forward the concept of “condition based maintenance” and apply its technology to the actual relay protection,we may “find the new land”.Based on the actual production,this paper studies and designs the condition maintenance system of the relay protection equipment,which can help the power enterprise managers make more scientific and effective maintenance plans and improve the operation reliability of the power system.The main research work of this paper is as follows:⑴ Compare the functionality,economy,and practicability of the traditional maintenance method and the condition maintenance method by consulting the literature and combining with the historical fault cause analysis in the actual production.The results show that state overhaul method meet the reliability requirements of today’s relay protection equipment better.The necessity of implementing condition based maintenance on relay protection is affirmed,and the basic idea of condition based maintenance is determined.⑵ Predict the optimal maintenance period of the relay protection equipment.The process of achieving this system’s function is as follows.First,establish the distribution model according to the data of the maintenance period,after analyzing,the Weibull distribution module is most suitable.Second,combine the least square method with the genetic algorithm and optimize the mixed method so as to estimate the parameters.Next,verify the hypotheses by using K-S test method and determine the failure rate function of the equipment through MATLAB simulation.Then,calculate the maintenance period meeting the requirements of reliability and minimum cost respectively,predict the optimal maintenance period by the fuzzy decision method.Finally,verify the feasibility of the algorithm by an example.⑶ Design and develop the system.After the comprehensive analysis of the varieties of requirements of the system,the system architecture can be designed according to the method of the B/S structure.In order to achieve the main functions,the system is divided into eight core modules: data acquisition,data processing,monitoring and early warning,condition diagnosis,condition evaluation,maintenance period prediction,risk assessment and maintenance decision-making.At the same time,the data management of the system is designed to determine the data source,establish the database,specify the data storage format of each data in the database and clarify the data interaction mode.Next,the system can be developed,the development environment and application environment can be determined.Lab VIEW is used as the development environment while Dreamweaver is used as the page design tool,both the login interface and the human-computer interaction interface of each major functional module are designed by DW.Finally,a numerical example is used to verify the practicability of the maintenance period prediction method in this system.