Research And Application Of Substation Circuit Breaker Monitoring System

Circuit breaker is an important power equipment in substation.As the control and protection unit in substation,it is an indispensable power equipment in substation.The safe and stable operation of circuit breaker is very important.With the increase of power consumption in China,the development of substation is gradually like the direction of high voltage and large capacity,which puts forward new requirements for the safety and reliability of circuit breaker.For the circuit breaker,the traditional detection method is regular maintenance.With the development of substation automation and intelligent requirements,regular maintenance has been unable to meet the requirements.Vacuum circuit breaker(VCB)is widely used in substations.The on-line monitoring technology of VCB has been proposed and applied in many substations.Aiming at the on-line monitoring demand of vacuum circuit breaker in a substation in Liaoning Province,this thesis takes the 12kvds-12 / 1250 vacuum circuit breaker of Shanghai Tianling switch Co.,Ltd.as the research object,an on-line monitoring system to realize the on-line monitoring of vacuum circuit breaker in the substation is designed and developed.Firstly,the monitoring theory of circuit breaker is studied,the classification and structure of circuit breaker are analyzed,and the common faults of circuit breaker are given.The mechanical characteristics and on-line monitoring parameters of the circuit breaker are analyzed.According to the monitoring parameters,the feasibility of on-line monitoring system is analyzed.Then the system design scheme is given,including hardware scheme and software scheme.The core processor of monitoring terminal is TMS320F28335,the current of opening and closing coil is obtained by Hall current sensor,and the formation time of moving contact of circuit breaker is monitored by rotary photoelectric encoder.The hardware structure design and sensor selection are given.The power supply unit,core processor unit,signal acquisition unit and data conversion unit are designed in detail.The implementation method and circuit design are given.In software design,the system development environment is given,and the main process and sub process design are introduced in detail.The monitoring terminal transmits the collected data to the background server through wired transmission,and the background server displays the monitoring circuit breaker data through expert software.The staff can know the operation of the circuit breaker through the background to realize the online monitoring function.After the completion of hardware and software design,the system prototype is debugged and the function is eliminated.Finally,the research results are put into operation in a substation in Liaoning Province.The system collects the collected data and makes a comparative analysis with the offline maintenance data.The operation results show that the research results are stable,and can accurately and real-time collect the circuit breaker operation data to meet the needs of on-site monitoring.