Measurement Of Compensation Capacitor In High-Speed Railway Communication System

With the rapid development of China’s high-speed railway,the ZPW-2000A rail communication system independently developed by China has been popularized on a large scale.However,the failure of the ZPW-2000A rail signal communication system often leads to serious high-speed rail operation accidents.Practice has proved that the biggest hidden trouble of ZPW-2000A communication system failure lies in the value decrease or even failure of the capacitance value parameter of the compensation capacitor in the middle of the railway.At present,most researches on this problem tend to use "software" methods,such as intelligent algorithms and artificial intelligence,to diagnose faults and troubleshoot damaged compensation capacitors;but this paper innovative proposes the combination of non-contact measurement technology and Internet of Things technology compensation capacitor The "hardware" solution of the detection to realize the collection of compensation capacitance data in one system.The main work includes:(1)Based on the analysis of the compensation capacitor circuit,an experimental scheme is constructed.The solution revolves around the three-layer IoT design architecture of sensor layer,transmission layer,and service layer,and realizes online real-time automatic measurement of compensation capacitance.(2)The Hall sensor based on the Hall effect realizes the non-contact measurement of the compensation capacitor circuit,and uses PSOC to digitize and local calculate the collected information of the sensor to realize the sensing layer.In order to realize remote online measurement,the LoRa series of IoT gateways and industrial 2G network GSM modules are used to implement the IoT transmission layer.For ease of use and visualization,a service environment based on Apache server,PHP server-side script and MySQL database is adopted to realize the service layer of the Internet of Things.At the transport layer and service layer,some information security considerations were made.(3)The solution can measure the current value passing through the capacitor non-contact when the simulated high-speed rail communication circuit works normally,and compare the empirical data of the technical reference manual,the error accuracy is within5%.The engineering experiment results show that the system detection scheme proposed in this paper is correct,which solves the problem of multi-node online measurement of current,and proves the feasibility and effectiveness of the scheme,which meets the engineering design requirements for detecting the capacitance value of compensation capacitors.