直流电弧加热器多电极运行技术试验研究

多电极运行是提高直流电弧加热器大电流运行可靠性的有效途径。通过对双阴极/单阳极和双阴极/双阳极电弧加热器多电极运行调试，探寻了镇定电阻匹配方式、气体流量和电流等参数对多电极中各电极电弧电流分配特性的影响。结果表明，镇定电阻匹配方式是影响多电极稳定运行的关键因素，气体流量和电流等运行参数对电弧电流分配影响较小；对于双阴极/单阳极电弧加热器，只有在内外阴极同时连接镇定电阻，并且满足一定电阻差时，才能将电弧电流稳定分配到各个子电极上；对于双阴极/双阳极电弧加热器运行时，不论内外阳极是否连接镇定电阻，只要内外阴极连接镇定电阻，电弧电流均可稳定分配到各个子电极，并且电流分配比例可根据镇定电阻的匹配方式进行调节；多电极运行时，宜选用电流分配均匀，电能损耗小的电阻匹配方式。

Experimental research of arc heater with multiple electrodes

The safely operation with multiple electrodes is important for arc heater running re-liability with large arc current.The influence of ballast resistor settings,gas flow and arc current were observed for arc heaters with a pair of cathodes matching single anode,and with a dual elec-trodes separately.Results show that the ballast resistor settings is the key factor for division of current between electrodes,and the operation parameters such as gas flow and current are insen-sitive with the arc current distribution.For arc heater with a pair of cathodes and single anode, ballast resistors with the certain difference connected simultaneously to inner and outer cathodes is a necessary for division of current between cathodes.For arc heater with a dual electrodes,the division of current between each electrode could be successfully achieved so far as the ballast re-sistors connected to cathodes.And the different current distribution proportions could be a-chieved by adjustment of the ballast resistor.When arc heater operated in multiple electrodes mode,the ballast resistor settings with lowest power loss and uniform division of current should be selected.