Medium Recovery Characteristics Of High-voltage SF₆ Circuit Breaker And Its Influencing Factors

With the development of electric power technology,the continuous upgrading of the national economy has promoted the development of the power industry to large units,long-distance,ultra/UHV and AC/DC applications.In order to ensure the safe and reliable operation of the power system,higher requirements for the electrical life of the high voltage electrical apparatus are put forward.Based on the study of dielectric recovery characteristics of high voltage SF₆ circuit breaker,the operation control strategy of circuit breaker is presented in order to meet the operation requirements of circuit breaker with high electrical life.The main research content of this paper is as follows:establish a description in the process of circuit breaker tripping over physical coupling field calculation model of arc to at the beginning of the arcing chamber load open circuit process of compressed air and air flow characteristic,modeling and simulation calculation.Setting up speed in the process of circuit breaker in the open circuit characteristic and the coupling mathematical model for calculating air characteristics,for different open circuit speeds,SF₆ circuit breaker arcing indoor SF₆ gas density,temperature,velocity,the change of macro parameters such as pressure characteristic simulation.At different pressures,the variation characteristics of the gas density,temperature,speed,pressure and other macroscopic parameters of SF₆ are simulated.The change of medium recovery characteristics of high voltage circuit breaker in different physical processes is analyzed.Analyze the above simulation results,get a different physical process of high voltage SF₆ circuit breaker the influence degree of the dielectric recovery characteristics,design and control of high voltage SF₆ circuit breaker has a guiding significance.