Research On High Voltage Electroscope Safety Alarm System Of High Voltage Transmission Line

With the continuous development of power industry,high voltage transmission technology has developed rapidly,and high voltage transmission lines have become an important part of power network in China.It is very important to ensure the normal operation of a large number of power equipment.At the same time,it is increasingly prominent to ensure the personal safety of operation and maintenance personnel.Therefore,higher requirements are put forward for the high-voltage electroscope as a tool of power safety.This project analyzes and summarizes the current research status of high-voltage electroscope.On the basis of the research on the high-voltage HVDC transmission electroscope of the project of China southern power grid,a non-contact high-voltage transmission line electroscope and safety alarm system are studied.First of all,the high voltage electroscope method based on electric field measurement is verified by simulation study of electric field distribution under high voltage transmission line.Compared with the electrical equipment in the station,the density of high-voltage transmission lines is not high,so the non-contact electroscope method based on electric field measurement has advantages for the line electroscope.A high voltage electroscope method based on vibration capacitance sensing technology is studied.The principle of measuring electric field by vibration capacitance sensor is explained through theoretical research.The simulation model is established by Maxwell finite element simulation software and the electric field calculation is carried out.The simulation results show that the electric field of charged body can be detected by the vibration capacitance plate when the vibration capacitance measuring module is placed in the high voltage electric field environment.Therefore,the method can be used in high voltage electric field measurement.Secondly,according to the research requirements of the project,a set of high-voltage transmission line electroscope and safety alarm system is designed and the system is composed of host computer,slave computer and upper computer.The host computer and slave computer are operated by two staff members separately during the electroscope.When the host computer determines that the object under test is live,the combined alarm of the host computer and slave computer is adopted to ensure the safety of the electroscope operation.The functions of the system are modular design,in which the sensor module is designed based on the principle of vibration capacitance,and the wireless communicationbetween host computer,slave computer and host computer is realized by ZigBee and GPRS technology,which constitutes a security alarm system.Finally,a high-voltage experimental platform was built to simulate the electromagnetic environment of high-voltage transmission lines.Functional experiments were carried out on the electroscope and safety alarm system to verify the feasibility of the method used in high-voltage electroscope.According to the requirement of HVDC(±160kV)transmission line electroscope,the parameters of electroscope and safety alarm system are set up,and the field test is carried out in the actual environment converter station.The results show that the developed system can detect the live state of transmission lines under high voltage electromagnetic environment.The method is stable,sensitive and can be applied both AC and DC.The alarm signals can be sent out in time.