[Show abstract][Hide abstract] ABSTRACT: High voltage circuit breakers are the most important protection and control apparatus in power system. As a core part of circuit
breakers, the operating mechanisms have a trend to be hydraulic-style in high voltage power grid. Compared with other hydraulic
systems, the hydraulic operating mechanisms have the characteristics of high hydraulic pressure, high speed, high power and
long-term waiting etc., and it is because of the characteristics that the hydraulic operating mechanisms become difficult
to be developed and have been arousing significant study interest from more and more researchers as well as their promising
applications. Therefore, it is significant to summarize the hydraulic operating mechanisms on their development, characteristics,
and key technologies etc. In this review, the evolution process and recent studies of hydraulic operating mechanisms at home
and abroad are viewed. The review then focuses on the characteristics and key technologies of hydraulic operating mechanisms,
especially on time and velocity characteristics, high-speed cylinder cushioning, fast response and great flow rate control
valve, temperature compensation, system monitoring and fault diagnosis, intelligent operation, energy storage module, etc.
In the end, the future trends of this field are presented.
Keywordshydraulic operating mechanism–high voltage circuit breaker–control valve–opening and closing motion–cushioning
[Show abstract][Hide abstract] ABSTRACT: Because of great harmfulness for greenhouse effect, SF6 gas has to be limited. It is necessary to develop high voltage vacuum circuit breaker to replace SF6 circuit breaker. Insulating structure and arc characteristics of vacuum interrupter are the key. For 72.5 kV vacuum interrupter, impulse voltage test is carried to find out factor of effecting on its insulating performance and insulating structure is improved. As a result, a design of 126 kV vacuum interrupter is presented and electric field distribution is calculated. Based on statistical property of breakdown in high voltage vacuum interrupter, its voltage withstand capability is analyzed. The relation between arc voltage and arc current, the influence of gap distance on arc noise is measured on 72.5 kV vacuum interrupter and the experimental results are analyzed.