一种电能表磁保持继电器拉闸方式的软件消弧设计

磁保持继电器在电能表中起着自动接通和切断作用,在电力行业起到重要的作用。但大电流拉闸可能导致磁保持继电器触点的损伤,多次损伤后导致继电器触点烧蚀粘连无法正常断开,严重时会酿成火灾。结合电能表的运行原理和负载的实际状况采用软件消弧设计实现电流过零拉闸,达到在大电流拉闸时保护磁保持继电器的目的。经对比试验验证,该拉闸方式对磁保持继电器触点有着更好的保护,将损伤降到一个相对较低的水平。

A soft design of the trip mode about electronic watt-hourmeter with magnetic latching relay to achieve arc suppression

Magnetic latching relay which has switch function in the electronic Watt-hour meter plays an important role in the power filed.But the trip under the condition of the large current can cause the injury of the magnetic latching relay contactor.Contactor can’t be open normally after multiple injury, and even cause fire.Combined with the actu-al load situation and the operating principle of the energy meter, this paper presents a soft arc suppression design means to achieve the zero current crossing trip and to protect the magnetic latching relay from injury caused by large current.Through comparative experiments, the zero crossing trip has the advantage of protecting magnetic latching re-lay in a better way and reduces the damage to the lower level.