Ice melting method for distribution network lines using zero-sequence current based on adjustable reactors

In recent years, due to significant global climate changes, the frequency of ice disasters has been steadily increasing. The existing AC and DC short-circuit ice melting technologies often cause line outages during the ice melting process, affecting normal production and daily activities. To address the issue of ice melting in distribution network lines, this paper proposes an online ice melting technology based on zero-sequence current regulation. The method involves the use of a grounding transformer and an adjustable reactor to form an integrated zero-sequence reactor device. By connecting the grounding wire with the end of the ice-covered line, a zero-sequence circuit is constructed for heating and ice melting. The grounding transformer extracts the neutral point to ensure that the ice-melting current is a zero-sequence current, while the adjustable reactor regulates the zero-sequence ice-melting current by adjusting the reactance value. Because the phase voltage on the load side can still maintain power supply during the ice melting process, it is possible to achieve online ice melting without power interruption. A case study of a 10KV line is provided to verify the effectiveness of the proposed method.