Simulation Study on Electrical Life Breaking Capacity of 550kV SF6 Circuit Breaker

The electrical life test of circuit breakers belongs to the type test of circuit breakers, which generally refers to the experimental evaluation of the arc extinguishing chamber and operating mechanism of the circuit breaker when developing a new type of circuit breaker, and the evaluation of its breaking capacity after multiple, continuous, and repetitive tests under standard conditions. However, circuit breaker products have complex structures and numerous components, making it time-consuming and labor-intensive to process and assemble a complete circuit breaker. Once the test fails, it is necessary to redesign the arc extinguishing chamber structure. Therefore, it is particularly important to effectively evaluate the breaking capacity of the circuit breaker before the test. The main consideration for the circuit breaker breaking process is the arc breaking. During the entire process, the plasma undergoes drastic changes. In order to better simulate and simulate this process, a simulation model was established in the software, and the airflow field simulation environment parameters were set. Before and after the electrical life test, the most intuitive change on the circuit breaker body is severe erosion at the nozzle, with significant changes in size before and after. Therefore, we considered the impact of erosion and established two simulation models of throat diameters to evaluate the electrical life breaking ability of the circuit breaker, providing effective guidance for completing the electrical life test of the circuit breaker. The successful application of this method indicates that when developing other types of circuit breaker products in the future, this method can also be applied to guide circuit breaker testing, in order to save costs and shorten the development cycle.