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Development of High Voltage Vacuum Circuit Breakers in China
2006 International Symposium on Discharges and Electrical Insulation in Vacuum, 2006This paper introduces research work on the development of high-voltage (HV) vacuum circuit breakers (VCBs) in China from its starting point in 1989 to 2006. In this period, a 126-kV two-breaks VCB prototype and a 126-kV single-break VCB prototype were developed. A latest 252-kV single-break interrupter prototype is introduced. Five HV VCBs technologies
Zhiyuan Liu +7 more
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The ins and outs of vacuum circuit breakers
Electronics and Power, 1975It has been known for some 40 years that one of the most effective ways of interrupting an a.c. circuit is to do so by means of contacts in vacuum. Unlike all other interrupters there is no gas in the arc, only metal vapour which condenses very rapidly as the current falls to zero, giving a most predictable performance and a very fast rise of electric ...
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Robust optimisation of the spring actuator in a vacuum circuit breaker
Mathematical Structures in Computer Science, 2014We present a concept of robust optimisation design for the spring actuator in a 10 kV/12.5 kA vacuum circuit breaker. We assume the breaking and closing velocity characteristics, which are derived form the technical data of the interrupter, as the specifications for the problem, and take the lengths of the connecting rods of the actuator and the ...
Gang Chen +3 more
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Maintenance-free vacuum circuit-breaker
Second International Conference on the Reliability of Transmission and Distribution Equipment, 1995The introduction of vacuum switchgear represented the first step in the direction of a maintenance-free medium-voltage circuit-breaker. Switching in a vacuum was the first quenching principle to assure constant electrical and dielectric properties throughout the device's entire service life of more than 20 years, involving for example more than 100 ...
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Diagnostics of the Vacuum Condition in Medium Voltage Vacuum Circuit Breakers
Conference Record of the 2008 IEEE International Symposium on Electrical Insulation, 2008In this paper some results of the field emission current measurements before and immediately after arc polishing of contacts as published in the literature are presented to show how single factors like contact geometry, contact surface, gas composition and pressure influence the results.
M. Koochack-Zadeh, V. Hinrichsen
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The role of vacuum in circuit breaker technology
2012 25th International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV), 2012Based on first installations of electrical energy systems at the second half of the 19th century, apparatus were needed to close and open electrical circuits under load and short-circuit conditions. Looking back to the origin of the development of these apparatus very different media have been used in order to switch electrical currents with the focus ...
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Vacuum interrupter for a generator circuit breaker
2013 2nd International Conference on Electric Power Equipment - Switching Technology (ICEPE-ST), 2013Improvements in vacuum interrupters (VI) have led to their increased use in generator circuit breaker (GCB). However, for power applications ≥ 100 MVA, increasing the thermal and short-circuit current rating of a VI is important. This paper discusses the VI design issues on improving the efficiency of its components.
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Simulation of reignition processes of vacuum circuit breaker in series
Proceedings of 17th International Symposium on Discharges and Electrical Insulation in Vacuum, 1997The present theoretical study is based on experimental investigations and shows the transient behavior of vacuum tubes in series, in the case of reignition. Neglecting the real physical arc and replacing it by a programmable switch (time controlled), it can be demonstrated, in a preliminary study, that the theoretical studies do confirm the ...
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Vacuum Technology as Basis for Production of Vacuum Circuit Breakers
2006 International Conference on Actual Problems of Electron Devices Engineering, 2006State-of-the art technologies which have been worked out for manufacture of vacuum tubes, mainly high-power microwave devices, proved to be a decisive feature shaping technical standard of vacuum circuit breakers ...
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