Real-time Microscopic Observation Test System of Electric Dendrite Characteristics in Solid Insulation Under DC Voltage

Abstract

The real-time microscopic observation test system for the characteristics of electrical dendrites in solid insulation under DC voltage, including an open container, a support seat is placed in the open container, and the sample to be tested is placed on the support seat. The needle electrode of the sample is connected to the high voltage lead through a high voltage copper column. , the plate electrode of the sample is connected to the low-voltage lead wire through the low-voltage copper rod. The design of the low-voltage copper rod, spring, and low-voltage copper column is helpful for the sample to be taken and placed and the position is fixed. The open container is covered by the container cover. The microscopic observation column inserted in the opening of the container cover can effectively weaken the sloshing of silicone oil in the area above the sample, and the direct observation window on the container cover is used for position observation and adjustment of the microscopic observation column; It can effectively fix the position of the sample, and it is convenient to take and place the sample. It can be applied to test samples of solid insulating electrical branches of different shapes and sizes. It can observe and take pictures of the needle tip area of ​​the sample in real time while applying DC voltage, without disconnecting. Electricity.

Description

technical field [0001] The invention relates to a microscopic observation test system for the characteristics of electric dendrites, in particular to a test system for real-time microscopic observation of the initiation and growth characteristics of electric dendrites in solid insulation under an external DC voltage. Background technique [0002] Due to the advantages of compact structure, convenient installation, easy maintenance, and environmental friendliness, solid insulated power equipment has been widely used in AC and DC transmission and distribution networks, and has replaced oil-paper and gas-insulated structures in many occasions. [0003] The study found that for high-voltage / ultra-high-voltage solid insulation, electrical dendration is the main cause of insulation failure. The research on the characteristics of electrical dendrites of solid insulating materials under AC voltage is extensive, mainly involving the influence of temperature, voltage amplitude, boost ...

AI Technical Summary

Problems solved by technology

[0007] When testing under AC voltage, the system can realize real-time observation and continuous recording of the sample; however, under DC voltage, the electrophoretic effect is extremely significant, silicone oil molecules move along the direction of the electric field and collide with the container wall, resulting in violent shaking of the liquid surface , it is impossible to observe the sample in real time or take a clear picture; in order to solve this problem, the method of applying voltage periodically and intermittently in the DC tree branch test is adopted. After the application time of DC voltage reaches the preset value, the voltage is reduced to zero. Wait until the liquid level of the silicone oil is calm before observing and taking pictures of the sample; this intermittent voltage application method is different from the way that electrical equipment withstands DC voltage during operation, which leads to doubts about the rationality of the obtained electric tree test results; It is necessary to establish a new test and observation system to be able to observe and photograph the electric tree in the sample in real time while continuously applying DC voltage

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