The Software Research And Realization On Subway DC-Fed Cable’ On-Line Monitoring System

In DC power supply system of subway, the DC-fed cable is a relatively weak link. Carrying out the real-tine and on-line monitoring research of the DC-fed cable, through on-line monitoring the change of cables’partial discharge (PD), can acquire the cable’insulation state and forecast its decaying trend.This paper gives an introduction of the background knowledge about the PD on-line monitoring technology, and has a discussion with the principle of partial discharge and PD model. Making use of the technology of partial discharge, achieves the function of on-line monitoring of the DC-fed cable.This article focuses on the software design and realization of DC-fed cable on-line monitoring system. The acquired PD signal from Data Acquisition unit, after the pre-processed by the Expert System, is extracted by Expert System for various parameters. The parameters extracted by Expert System are used to build the feather map to access the state of the cable insulation. Based on the .NET platform, with the object-oriented design mode, mainly using the programming language C#, the software system has realized functions of PD data collection, data storage, data processing with MATLAB algorithms in .NET platform, etc.