煤矿供电系统发生故障时,会危及到供电系统安全运行,其中最常见也是最危险的故障就是供电短路,不但烧毁设备、影响正常生产,在井下还有引起瓦斯爆炸及煤尘爆炸的危险。因此,要求保护装置当供电系统发生故障时,能自动、迅速有选择地将故障设备从供电系统中切除,以保证系统中非故障部分正常运行。 Coal mine power supply system failure, it will endanger the safe operation of power supply system, one of the most common and most dangerous fault is the power supply short circuit, not only burn the device, affecting normal production, there is also caused underground gas explosion and coal dust explosion danger. Therefore, the protection device is required to automatically and promptly and selectively remove the faulty equipment from the power supply system when the power supply system fails, so as to ensure normal operation of the non-faulty part of the system.