Test method, test circuit and design method of withstand characteristic of lightning protection insulator

Abstract

The disclosure relates to a test method, a test circuit and a design method for the withstand characteristic of a lightning protection insulator. The test method includes acquiring the impact energy absorbed by the entire lightning protection insulator under the first impulse current wave; acquiring the impact energy under the second impulse current wave current and corresponding thermal stress; respectively obtain the power frequency reference voltage and leakage current corresponding to the first and second surge current waves; adjust the surge current applied to the entire lightning protection insulator according to the change rate of the power frequency reference voltage and the comparison result of leakage current ; Perform the above steps in a loop until the power frequency reference voltage change rate is less than or equal to the set rate of change, and the leakage current is less than or equal to the set leakage current. subject to the maximum value. Through the technical proposal of the present disclosure, the response characteristics of the entire lightning protection insulator when it is directly struck by a large current are truly simulated.

Description

technical field [0001] The embodiments of the present disclosure relate to the technical field of electrical equipment testing, and in particular, to a testing method, testing circuit and design method of a lightning protection insulator's withstand characteristic. Background technique [0002] With the development of the economy, the speed of my country's power grid construction has gradually accelerated in recent years. Due to the long transmission distance and wide spanning range, transmission lines often have to pass through some high-altitude mountainous areas with complex terrain, resulting in serious problems of lightning damage in summer and icing in winter. Accidents such as trips, power outages, and equipment damages caused by icing flashovers also occur from time to time. In order to improve the ability of transmission lines to resist lightning strikes and icing disasters, lightning protection insulators can be used to protect against lightning strikes and icing di...

AI Technical Summary

Problems solved by technology

However, theoretical analysis and on-site operation results show that: during the impulse current test of a single-chip zinc oxide resistor, the resistor is directly exposed to the air environment, and when the entire lightning protection device is formed, multiple resistors in series have been sealed and packaged. The energy and pressure generated by the high-current impact cannot be released quickly, resulting in a smaller surge current withstand capacity of the entire lightning protection device than a single-chip resistor. Therefore, the single-chip zinc oxide resistor and the ratio The surge current withstand characteristics of the unit cannot simulate the actual situation of the entire lightning protection insulator being directly struck by lightning current under the operating conditions

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