On-line Monitoring System of Metal Oxide Arrester Based on LabVIEW
|Course||High Voltage and Insulation Technology|
|Keywords||Zinc oxide surge arresters Online monitoring LabVIEW|
Zinc oxide arrester (MOA) with its protection features good flow capacity, reliable action and maintaining the advantages of simple, protected AC electrical equipment from lightning over-voltage and operation overvoltage damage equipment. MOA long-term, however, suffer from the weather, temperature, lightning, operating voltage and internal moisture and other factors, the aging, the protection function may lead to serious failure, affect the safe operation of the power system. Therefore, the MOA's run accident prevention, its online monitoring significant insulation condition. In this paper, based on analysis of the status of the MOA line insulation monitoring and line insulation monitoring the general principle of the metal zinc oxide surge arresters (MOA) resistive current online monitoring, the key is the total leakage current from the resistive and capacitive symbiotic isolated weak resistive current characteristics, design a line insulation monitoring system based on virtual instrument technology and LabVIEW software to complete the MOA insulation online monitoring system hardware and monitoring software design, production, and the whole system debugging . Selected on the basis of the principle and the advantages and disadvantages of the analysis comparing several the MOA-line insulation online monitoring methods, monitoring MOA Resistive Leakage current harmonic analysis method, the use of software technology isolated resistive current fundamental component and harmonic components of change in relations between the two to determine the reasons for the decline caused by the MOA performance or moisture, aging of the valve plate to complete and reflect the running condition of the MOA. And analyze the cause of the main error of the harmonic analysis, and proposed solutions. Then, according to the characteristics of the the MOA insulation online monitoring system, designed a system of hardware and software solutions. Sensor selection is completed, the data acquisition card selection based on signal preprocessing circuit design, to build a system of hardware platforms; harmonic obtained fundamental resistive current folding and Access2007 database system data management; then establish a server based in the use of Ⅱ S NET network programming, network monitoring data queries; Finally, based on LabVIEW software platform, system software design. In this paper, the design of online monitoring system after system commissioning and field data show that effective monitoring of MOA Resistive Leakage current with high accuracy and stability.