Low-impedance lightning protection system of high-voltage circuit

The invention relates to a low-impedance lightning protection system of a high-voltage circuit, belonging to the technical field of lightning protection grounding of the high-voltage circuit and aiming to solve the technical problem that a transient potential of a high-voltage power transmission system is risen sharply to cause tripping because the ground potential is risen, lightning current cannot be released timely and the lightning current intrudes into a station along the power transmission circuit when the circuit encounters lighting stroke and the lightning current enters the ground through the down lead since lightning arresters of three phases A, B and C of an overhead power transmission circuit in the prior art share a down lead. The low-impedance lightning protection system comprises the lighting arresters and the down lead and also comprises a low-impedance absorption-type grounding device, wherein the absorption-type grounding device is arranged under the ground, the lightning arrester on each ci