Method for evaluating high temperature aging degree of DC cable insulation material based on compound field

Abstract

The invention discloses a method for evaluating high temperature aging degree of a DC cable insulation material based on a compound field. A cumulative damage method is adopted to effectively evaluatethe insulation state of an insulation material for a DC cable. The method comprises the following main steps: first, preparing a polypropylene sample based on a pin-plate electrode; then, carrying out the experiment by using an electric branch experiment system device under a high temperature environment; secondly, observing the aging situation of the electric branch of the sample; finally, calculating by using the Matlab language. The pin-plate electrode system simulates the inevitable defects inside the DC cable and effectively simulates the working conditions of the DC cable in the actualoperation.

Description

technical field [0001] The invention belongs to the field of high-voltage equipment, and particularly relates to a method for evaluating the high temperature aging degree of a DC cable insulating material based on a composite field. Background technique [0002] In HVDC cables, the temperature of the cable insulation is related to the cable load. At full capacity, the current flowing through the cable conductors produces temperatures as high as 90°C. This temperature is already much higher than room temperature. However, it can reach as high as 150 °C in a short time during the fault, which seriously affects the safe operation of the power cable. For the operation process of the high-voltage DC cable, it is under a certain amplitude of DC voltage, but the pulse voltage introduced due to lightning strike, commutation failure, operating overvoltage and other reasons will have an adverse impact on the working environment and easily cause cable insulation. The aging and break...

AI Technical Summary

Problems solved by technology

However, it can be as high as 150°C in a short period of time when a fault occurs, which seriously affects the safe operation of power cables.

For the operation process of high-voltage DC cables, they are under a certain amplitude of DC voltage, but the pulse voltage introduced due to lightning strikes, commutation failures, operating overvoltages, etc. will have an adverse impact on the working environment and easily cause cable insulation. The aging and breakdown of electrical branches seriously threaten the safety and service life of cable insulation

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