Research On Partial Discharge Vehicle Patrol Instrument For Polluted Insulators

Security and stability of power system is very important. To ensure the reliability of insulators is the most important task to ensure system security and stability. Dirtiness has a very big impact on insulator reliability. In a variety of the power system accidents, the loss caused by pollution flashover takes a very large proportion. It is a consensus that pollution flashover causes serious harm to power system.Domestic and foreign scientists have made a thorough study on the methods of how to prevent pollution flashover, expected to reduce pollution flashover accidents by monitoring. Nowadays, the main method at home and abroad is Equivalent salt concentration method and Leakage current method. But these two methods can only be used for targeted monitoring in heavily polluted areas, and can't be widely used.Taking into account the occurrence of partial discharge on polluted insulator will produce high-frequency electromagnetic waves, this paper proposes the method of using ultra-high frequency electromagnetic wave monitoring technology to monitor the polluted insulator flashover, and design Mobile Partial Discharge Detector for Polluted Insulators. The monitoring equipment has a very high accuracy and low cost. It is practical, and can be widely used.This paper preliminary designs hardware and software architecture of the pollution flashover monitor. The hardware part of the instrument mainly makes up by the antenna, high-frequency amplifier, filter circuit, the detector circuit, A / D conversion, the core chips. According to electromagnetic waves generated by partial discharge characteristics on polluted insulator, select the appropriate bands of the antenna to receive electromagnetic signals, and then the signals pass through high-frequency signal amplification, allowing the signals to have sufficient load capacity, and through the filter circuit to remove some of the background interference, then through detector circuit to extract the voltage peak and reduce the A/D converter's input frequency, and finally through the sample and hold circuit and A/D conversion circuit ,input to the microcontroller processor for analysis and processing. The instrument's software part of this paper, complete with the program design of a USB interface, LCD display, power supply control part.This paper theoretically demonstrated the feasibility of the method using ultra-high frequency electromagnetic wave to monitor polluted insulators, and preliminary designs hardware and software architecture of the pollution flashover monitor, also has high practical value.