Analysis on principle of operation of arc-suppression coil based on thyristor controlled reactor

In distribution systems the following grounding ways, i.e. non grounding, arc-suppression coil grounding and arc suppression coil via small resistance grounding, are often applied. Because each grounding way has its own features, therefore, it is necessary to carry out technical economical comparison before select ion for the particular case. In 6 kV coalmine power system, the transmission lines mostly are cables, the grounding current is almost capacitive current, so arc-suppression coil grounding is widely used in coalmine power system. This paper presents a new type of arc-suppression coil, then focus on study of the compensatory principle of arc-suppression coil with three phases and five columns. The structure of this arc-suppression coil is different from the traditional mode, and it is the integration of the traditional grounding transformer and arc-suppression coil. The arc-suppression coil with three phases and five columns can realize automatic trace and compensation for grounded fault capacitive current of power system by the method of regulate the thyristor triggering angle to control the inductive current of second winding. The wave shape of the arc-suppression coil with three phases and five columns is also analyzed and calculated in this paper.