Lightning arrester grounding overvoltage protection device and using method thereof

Abstract

The present invention provides a lightning arrester grounding overvoltage protection device and a using method thereof. A push rod motor is arranged on the lower side of the lightning arrester, and when a grounding fault occurs in a system, a controller controls the contraction motion of the push rod motor, and a non-fault phase (a voltage rising phase) is connected in series with the divider resistor, so that the voltage borne by the lightning arrester is reduced to protect the lightning arrester from being broken down; in a normal state, the push rod motor is controlled to extend out to isolate the divider resistor, so that the loss of the lightning arrester in an overvoltage state is effectively avoided.

Description

technical field [0001] The present disclosure relates to the technical field of surge arrester overvoltage protection, in particular to a surge arrester grounding overvoltage protection device and a use method thereof. Background technique [0002] The statements in this section merely provide background information related to the present disclosure and do not necessarily constitute prior art. [0003] Surge arrester is a system overvoltage protection device commonly used in power grid operation. It is responsible for limiting various overvoltages in the system caused by lightning strikes, harmonics and operations, etc., and plays a vital role. In real life, zinc oxide arresters are widely used. The inventor found that the operation safety of the arrester itself is easily ignored. As the arrester continues to withstand the impact of overvoltage, its performance will gradually deteriorate, mainly manifested in the increase of leakage current. The process is relatively slow a...

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Problems solved by technology

In real life, zinc oxide arresters are widely used. The inventor found that the operation safety of the arrester itself is easily ignored. As the arrester continues to withstand the impact of overvoltage, its performance will gradually deteriorate, mainly manifested in the increase of leakage current. The process is relatively slow and has a certain degree of concealment. If it is not discovered in time, breakdown faults are very likely to occur. Although the value of the arrester body is not high, once an explosion accident occurs, the system will be blacked out, and production will be interrupted, resulting in the immeasurable indirect loss of

[0004] During the operation of the power system, the single-phase ground fault is the most common fault. After a single-phase ground fault occurs on the 10kV distribution line, the PT (potential transformer) on the 10kV bus of the substation detects the zero-sequence current, which is generated on the open triangle. Zero-sequence voltage, PT iron core saturation, excitation current increases, such as long-term operation, will burn the PT; single-phase ground fault may also cause resonant overvoltage; resonant overvoltage several times the normal voltage, endangering the insulation of substation equipment , In severe cases, the insulation breakdown of the substation equipment is caused; the inventor found that when a single-phase ground fault occurs, intermittent arcing grounding will occur, resulting in a resonant overvoltage, which will generate an overvoltage several times the normal voltage, causing the breakdown of the line insulator , causing serious short-circuit accidents, and at the same time, there is a risk of burning some defective distribution transformers, causing breakdown or burning of arresters on the line, affecting the normal operation of the power system

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