Recently, the State Grid Corporation major science and technology project "UHV engineering with high electrical life switch capacitor switchgear research and engineering applications" passed the company's acceptance. This project is led by China Electric Power Research Institute. The project succeeded in developing a capacitor bank circuit breaker with a power life of 3000 times, which provided strong support for the selection of UHV engineering equipment.
As the main means of system reactive power and voltage control, the switch of the UHV system capacitor bank requires over 3000 electrical lifetimes, and the maximum life of the existing products is only 1200 times. Therefore, it is urgent to carry out the key technologies of the switch of high electrical life Capacitor Banks Research and prototype development. For the first time, this project proposed the electrical life test scheme of capacitor bank switch, the arc contact closure erosion mathematical model and the opening and closing characteristic simulation and measurement method. A 145 kV capacitor bank current opening and closing test circuit was built and a 126 kV high Electrical life of the capacitor bank circuit breaker (without phase selection of electricity life of 1200 times, phase selection of electricity life 3000 times), to fill the gaps in the world to reach the advanced world level.
The project achievements can meet the construction needs of UHV projects and can greatly solve the similar problems of EHV systems of 750 kV and below, significantly improve the opening and closing performance and reliability of the switch of capacitor banks, and ensure the safe and reliable operation of the power grid.
