直流场下基于平板电极的油流带电特性研究（英文）

Research on Oil Flow Electrification under DC Field Using Plane Electrodes

变压器是特高压直流输电系统中的重要设备之一,其运行的稳定性直接影响到整个输电系统的安全运行,而油流带电已经成为危及换流变压器安全稳定运行的普遍性问题。为了研究直流电场下油流带电的产生机理,设计并搭建了基于平板电极模型的油流带电实验系统,并研究了正极性电压和负极性电压对油流带电特性的影响;通过改变油纸层数,研究了正、负极性电压下电极注入电荷对油流带电特性的影响。研究发现:正极性电压下,冲流电流为正值,且随着施加电压幅值的增加而增大;负极性电压下,冲流电流随着施加电压幅值的增加先略有增加,而后下降并反向增长;油纸层数增加时,冲流电流值呈减小趋势,说明直流电压作用下油流带电不仅与偶电层的电荷分离有关,电极电荷注入也成为影响油流带电的因素。

As the key power equipment in the DC power transmission system, the transformer affects the reliability of the entire system.However,flow electrification becomes more and more non-ignorable.In Order to investigate the flow electrification that always happens in transformers, the experimental system with plane electrode is built up.Effects of voltage polarity and paper layers on flow electrification are studied.It is found that ,under positive voltage ,flow current shows positive, and increases with the increase of applied DC voltage.However, under negative voltage ,flow current firstly increased a little bit, and then increased reversely with negative polarity.Meanwhile,with the increase of paper layers,flow current becomes smaller,which clarify that flow electrification not only depends on the charge separation from the electrical double layer, but also depends on the charge injection from the high-voltage electrode.