真空中电流转移开断策略及其调控机理研究

Abstract: In recent years, vacuum circuit breakers are increasingly demanded in medium voltage occasions of power system, like generator protection, ship, subway, etc. Lots of researches have been done to achieve the AC/DC fault interruption. AC operating in parallel (synchronous transfer) and DC forcing the zero-crossing switching (asynchronous transfer) are two typical current transfer methods. As the interruption in vacuum is different from the gas arc, the current thansfer in vacuum has its own characteristics. The breaking moment of the first phase in synchronous transfer will affect the transfer time, and the zero-crossing interruption of the later phase. In asynchronous transfer, the investing time and the slope of transfer current, as well as the features of the actuator, have a great influence on the rate of breaking success. This program is intended to analyze the corresponding dynamic factors in the current commutation. Furthermore, a mathematic model is made to correct the parameters of the transfer process. The dielectric recovery in the gap is detected and images are measured by High Speed Photography, in order to find out the regulation mechanism and analyze the impact of dynamic factors. Combined with phasing-control switching, the flexibility and the success rate will be enhanced, which provides guidance for application of current tranfer in vacuum.

摘要：近年来电力系统中发电机保护、舰船、地铁等中压用电场合对真空断路器的要求越来越高，真空中采用电流转移原理来实现交、直流故障开断得到了较多的研究。交流并联运行（同步转移）和直流强迫过零开断（异步转移）是两种典型的电流转移方式，由于和气体电弧的特性不同，真空中电流转移的开断特点也不相同。同步转移中首开相的真空电弧，会导致转移时间跟随开断时刻发生变化，对后开相的过零开断有着较大影响。异步转移中，转移电流的投入时刻、投入斜率、操动机构的开断特性等对开断的成功率也有较大的影响。本方案拟对影响真空中电流转移开断的动态因素进行分析，对转移过程进行数学建模和参数校正。采用高速摄影仪对电弧图像进行采集，转移开断后测试弧隙中介质恢复情况，来分析影响电流转移开断的动态因素，并找出其调控机理。结合选相开断策略，增强其分断灵活性和成功率。为真空中电流转移开断的实用化设备的研制提出指导意义。

近年来电力系统中发电机保护、舰船、地铁等中压用电场合对真空断路器的要求越来越高，真空中采用电流转移原理来实现交、直流故障开断得到了较多的研究。交流并联运行（同步转移）和直流强迫过零开断（异步转移）是两种典型的电流转移方式，由于和气体电弧的特性不同，真空中电流转移的开断特点也不相同。同步转移中首开相的真空电弧，会导致转移时间跟随开断时刻发生变化，对后开相的过零开断有着较大影响。异步转移中，转移电流的投入时刻、投入斜率、操动机构的开断特性等对开断的成功率也有较大的影响。本方案拟对影响真空中电流转移开断的动态因素进行分析，对转移过程进行数学建模和参数校正。采用高速摄影仪对电弧图像进行采集，转移开断后测试弧隙中介质恢复情况，来分析影响电流转移开断的动态因素，并找出其调控机理。结合选相开断方式，增强其分断灵活性和成功率。为真空中电流转移开断的实用化设备的研制提出指导意义。