Design And Study Of On-line Monitoring Software Based On UHF Method

As the society develops, the reliability of the electric equipment is requiredhigher and higher. Many serious electricity blackout accidents have taken placebecause of the insulation problem of the equipment. By using the partialdischarging monitoring technique, the insulation deterioration can be detected atthe early stage, thereby prompt maintenance can be carried out and avoid theaccidents. Therefore, we developed a software for the online monitoring system ofthe ultra-high-frequency partial discharging of the gas insulated switchgear(GIS).This paper first introduces the importance of the development of the onlinemonitoring technique for the partial discharging of the GIS, and then introduces itsdomestic and foreign research status. The mechanism of this technique is alsointroduced. There are more and more online monitoring equipment being developedfor the partial discharging of the GIS. These equipment can be divided into severalkinds and the software is developed according to the specific equipment. To meetthe users’ real needs and alleviate the analysts’ workload, we systematicallyintegrate the relevant functions into the software and use the software developmentmode of the large enterprises to develop a monitoring software.According to the idea above, we design the framework of the onlinemonitoring software and select the VC++as the development tool. According to therequirements of the online monitoring, the communication interfaces of RS–485,Ethernet, PCI and CAN are designed and the relative software modules aredeveloped. Because the Matlab has powerful functions in the engineering, acommunication interface is reserved for it during the software development,according to the features of the VC++and MATLAB. This interface facilitates thesubsequent analyses of the partial discharging monitoring data and the malfunctiondiagnosis.The statics based method is adopted to recognize the partial discharging mode.The collected partial discharging data is analyzed through the graphics, such as theflame figure, which shows the phase–discharging capacity–maximum dischargingcapacity(φ-q-qmax) and the phase–discharging capacity–discharging times(φ-q-n),and the discharging trend figure which shows the time–discharging times(t-n).Additionally, the three–dimensional visualization method is used to show thephase–discharging capacity–discharging number(φ-q-n).Finally, according to the software testing principal, the software is strictly tested, including the interface test and the dynamic test. The static test of the codesis carried out by using the professional C++testing software. Additionally, asystematic testing environment is set up to simulate the peripheral equipment totest the reception, transmission and display of the data. The testing results showedthat this software can be used to monitor the partial discharging of the high-voltageGIS online. In addition, this software can has good versatility and it can beupgraded to monitor the partial discharging of other electric equipment, such as thetransformer and the high-voltage cables.