WSN Based On Capacitive Equipment On-line Monitoring Substation Applied Research And Engineering Practice

The safe operation of high voltage electrical equipments plays an important role in guarantee ensuring the safe, stable and economic operation of power system. Generally speaking, the quantity of capacitive high-voltage equipments account for40percent～50percent of the total number of substation equipments, which is such a type of equipments who is prone to accident, in addition, has a heavy workload of preventive tests. The good or bad performance of insulating property plays a key role in affecting the life of capacitive power equipments. According to statistics,80percent of accidents in high voltage power system belonged to insulation breakdown. In order to reducing and even put an end to insulation breakdown, in addition to improving the structure of insulating property, it is also important to require the operation department to improve the standard of line insulation monitoring and fault diagnosing.The monitoring of capacitive equipment insulating property is based on the diagnosing about the dielectric loss tanδ, the leakage current Ⅰ and the capacitance C. Among these, tanδ is an important basis for reflecting the general situation of such type of equipments. So, the insulation monitoring of capacitive equipments is a very significant way to implement the condition-based maintenance effectively. The theory of dielectric loss could be summarized that convey the current signal and the voltage signal of the measured pieces to the test principal machine, compare the phase position of the two signals then, finally, obtain the dielectric loss of the equipments.The existing on-line monitoring of capacitive equipment is mostly through laying of cable to lead the voltage of high voltage equipments from PT to capacitive equipment location, the above mentioned action can achieve the synchronous measurement about leakage current and voltage, and obtain the dielectric loss, or in another way, we can estimate the insulating property good or bad by monitoring the insulation leakage current. The article analyses the wireless communication technology on the basis of the objective reality of an110kV YunNan station. By the means of outputting signals on the base of Zigbee technology, laying wire in station has been avoided and the convenience of flexible increasing or decreasing in node has been provided in the future. The time synchronization mode with GPS is used in setting time to the leakage current and voltage in the whole station, which ensures that measurement accuracy meets the requirement of the station. Aim at the actual situation of the station, equipment research and development successfully completed as well as testing in the laboratory, which ensures that measurement accuracy, communication distance, anti-jamming capability and communication quality can meet the requirement of the station. Based on the technology platform of CyberControl, we build a model of a capacitive equipment on-line monitoring system in this1lOkV station. Solve questions appeared during the actual installation process and complete the installation and commissioning of the whole110kV station distributed capacitive equipment on-line monitoring system.