| With the continuous improvement of domestic capacity and voltage degree of the electric transmission line in power system, the reliability requirements of operation power grid is essential. As the important control and protection device in the electrical power system, effective coordinates both the hydraulic operating mechanism and arc extinction noumenon, which decides the operating performance of the circuit breaker. The hydraulic operating mechanism is considered as the core component, and theoretical and experimental analysis of the operation performance is crucial to study the interrupting property.In this thesis, actual structure of the circuit breaker is studied, based on the structure, the working principle and its hydraulic operation mechanism are analyzed. By means of the application of the mechanical dynamics, fluid mechanics, hydraulic transmission, electro-magnetics and computer science, based on the law of conservation of energy, the first law of thermodynamics, state equation of gas and the equations for fluid flow, the load reaction model and factor of linkage transmission ratio is introduced, and the model of the combination of the arc-quenching chamber and hydraulic operating mechanism is deduced.The characteristics of the opening stroke versus time and velocity versus time for the1100kV ultra high voltage (UHV) SF6circuit breaker under no-load are obtained by the theoretical simulation and experimental analysis, and the influences of hydraulic operating mechanism structural parameters on the characteristics of velocity and stroke has been analyzed. Moreover the comparison of the simulation and test has been analyzed. And the pressure characteristic under the load and no-load condition has been performed. Based on the simulation and analysis of the hydraulic operating mechanism for the550kV circuit breaker, the comparison of the simulation and test of the velocity, accuracy and the feasibility has been obtained.In addition, the cylinder diameter, piston diameter, cylinder wall thickness, system pressure, piston stroke and the pressure of the arc quenching chamber has been calculated and analyzed. Moreover, the action time and delay of the control valve system has been discussed.By simulation the operating mechanism and arc-quenching chamber in the process, the operating characteristics analysis is realized. By the comparison between experimental and numerical simulation, the numerical analysis reference for researching and developing the SF6UHV circuit breaker has been provided. |
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