The Research On Dynamic Characteristics Of Hydraulic Actuator For550kV Super High Voltage Circuit Breaker

In the power system, the circuit breaker is the critical part in controlling the power line and protecting the power system. In various components of the circuit breaker, the hydraulic actuator is the driving part of the switching element. The unreasonable structural design of the hydraulic actuator directly influences the performance and the reliability of the circuit breaker. So the excellent performance and high reliability of the hydraulic actuator have become the focus and the difficulty in current research of the circuit breaker.In this paper, the hydraulic actuator of550kV circuit breaker is the object of the research. Based on the theory of fluid mechanics, hydraulic transmission, modern control and the efficient power bond graph modeling tool, the main components and the system of the hydraulic actuator are simulated by the software20-sim which supports the power bond graph. From the results of the simulation, the impact of the structural parameters of the actuator on the closing process, opening process and cushioning process is analyzed and the structure is optimized in order to improve the performance and the reliability of the hydraulic actuator.The main work of this paper is followed:(1) Refer to the relevant literature and design information of550kV super high voltage circuit breaker, the structural characteristics, the composition and the working principle of the hydraulic actuator are analyzed. Based on power bond graph modeling and simulating software20-sirn, the hydraulic system of the actuator is simulated and calculated. The characteristic curves of various components in the closing and opening process are obtained providing the basis for the research of the hydraulic actuator’s dynamic characteristics.(2) While the hydraulic actuator system has the characteristics of high pressure and large flow, the dynamic characteristics of the system cannot be ignored. Through the analysis of structural parameters, the impact of different parameters on opening and closing velocity is summed up, and based on the simulating results of the analysis, the closing and opening velocity are optimized.(3) Considering the high cushioning pressure has a serious impact on the performance and life of components, the impact of different cushioning structural parameters on the cushioning pressure peak is processed through sensitivity analysis. According to the sensitivity, the cushioning structure is optimized to reduce the cushioning pressure peak providing the reference for the actual cushioning design.