大电流开关电器并联支路中的电流分配

Current Distribution in Large Current Switch Apparatus Parallel Branch

大电流开关电器的并联支路中存在电流分配不均匀性。直流电流时,其不均匀程度取决于各并联支路中电阻的差异;交流电流时,则主要取决于并联支路中电抗的差异,支路附近导体中电流产生的互感,也即邻近效应使并联支路构成的回路中生成环流,是致使电流分配不均匀的主要原因。对电流分配不均匀性和一些测试数据进行了分析,并提出在设计和使用具有并联支路的大电流开关电器时,为使电流分配更趋均匀应注意的问题。

There exists current distribution unevenness in large current switch apparatus parallel branch. In DC current, its unevenness degree depends on the differences of resistance in each parallel branch; in AC current, it depends on the differences of reactance, the inductance mutual produced in branch circuit neighboring current that is to say neighboring effect enabling the loop current generated in the circuit confiqurated by parallel branch, which is the main cause to result in current distribution unevenness. Analysis was carried out for current distribution unevenness and some data tested, and some questions are raised in order to make current distribution to be evener in design and use of large current switch appliance in parallel branch.