Device and method for testing external insulation delay coefficient under VFTO and atmospheric overvoltage

Abstract

The embodiment of the invention discloses a device and method for testing an external insulation delay coefficient under the VFTO and atmospheric overvoltage. A signal input end of a pulse generatingunit of a double-pulse generating device is electrically connected with a triggering control module of a signal generating controller, and the signal output end of the pulse generating unit is electrically connected with the first ends of a first high-voltage pulse cable and a second high-voltage pulse cable. The second ends of the first high-voltage pulse cable and the second high-voltage pulse cable are connected with an external insulation testing device. An insulation information collection and processing device is connected with the external insulation testing device. The signal generating controller controls the double-pulse generating device to generate the VFTO and the atmospheric overvoltage signals, and applies the generated VFTO and the atmospheric overvoltage signals to an external insulation sample in the external insulation testing device. The n insulation information collection and processing device collects an external insulation delay coefficient after action, and obtains the influence of the external insulation sample on the external insulation strength under the VFTO and atmospheric overvoltage.

Description

technical field [0001] The present application relates to the technical field of electrical system external insulation testing, in particular to a test device and method for external insulation delay coefficient under VFTO and atmospheric overvoltage. Background technique [0002] Due to its good insulation performance, low line loss and large transmission capacity, high-voltage inflatable lines are widely used in various UHV power transmission projects such as "West-to-East Power Transmission" in my country, and are an important part of the power system . During the operation of the high-voltage inflatable line, it is seriously affected by the phenomenon of lightning discharge in the external environment, and the external insulation of various high-voltage equipment connected to it has been subjected to atmospheric overvoltage for a long time. Atmospheric overvoltage refers to the sudden addition of direct lightning or lightning induction to the power system, causing the el...

AI Technical Summary

Problems solved by technology

During the opening and closing process of the isolating switch in the high-voltage inflatable line and the ground fault process, the external insulation of the high-voltage equipment is also very vulnerable to the impact of VFTO (Very Fast Transient Overvoltage), resulting in serious damage to the external insulation performance of the high-voltage equipment

[0004] However, in actual engineering, only the power frequency withstand voltage test is performed on the external insulation of electrical equipment before it is put into operation, and it is impossible to test the performance of the external insulation of high-voltage equipment under VFTO and atmospheric overvoltage. In addition, due to VFTO and atmospheric overvoltage Occurrence is accidental, the duration is short, and it is difficult to capture. Therefore, it is impossible to accurately know the impact of the above effects on external insulation when VFTO and atmospheric overvoltage are combined.

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