Application of DC High Voltage Generator in High Voltage Testing

DC high voltage generator is a lightweight, reliable, and high-precision DC high voltage generating device used in power system high voltage testing. It is mainly used for DC withstand voltage and leakage current testing of power cables, transformers, lightning arresters, insulators, and other equipment. It is a key equipment for judging the insulation condition of electrical equipment.

1、 Application in Preventive Testing of Power Cables

The most typical application of DC high-voltage generators is to conduct DC withstand voltage tests and leakage current measurements on medium and high voltage cross-linked polyethylene cables and oil paper insulated cables. By applying a negative polarity DC high voltage, defects such as bubbles, cracks, impurities, and mechanical damage in the main insulation of the cable can be effectively detected, and hidden dangers such as moisture, aging, and local breakdown can be detected in a timely manner. This provides a direct basis for cable operation, maintenance, and condition assessment, ensuring the safe operation of the line.

2、 Application in Zinc Oxide Surge Arrester Test

Zinc oxide lightning arrester has no gap and strong non-linear volt ampere characteristics. DC reference voltage testing and leakage current testing at 0.75 times DC reference voltage must be completed using a DC high-voltage generator. By accurately applying high DC voltage, it is possible to determine whether the valve plate of the lightning arrester is damp, aged, deteriorated, or if the internal components are damaged, avoiding the explosion and breakdown of the lightning arrester during system overvoltage and ensuring its normal overvoltage protection function.

3、 Application in Insulation Testing of High Voltage Transformers and Transformers

Conducting DC withstand voltage and insulation leakage tests on power transformers and voltage/current transformers can verify the overall performance of the main insulation and longitudinal insulation. The DC high-voltage generator can effectively expose defects such as insulation moisture, oil degradation, winding deformation, interlayer short circuit, etc. without damaging good insulation. It complements the AC withstand voltage test and comprehensively evaluates the insulation strength and operational reliability of the main equipment.

4、 Application in high-voltage switch and insulator detection

Used for DC insulation testing of high-voltage circuit breakers, isolating switches, post insulators, bushings, and other equipment. By measuring changes in leakage current, it is possible to determine whether there is contamination, cracks, or damage in the outer insulation, as well as whether there is moisture or air gap discharge in the inner insulation. This is particularly suitable for rapid on-site testing and provides data support for the maintenance of switchgear, busbars, and insulation components.

5、 Application in on-site high-voltage testing and handover acceptance

DC high-voltage generators have the characteristics of small size, light weight, stable output, and easy operation, and are widely used for on-site handover and preventive testing in substations, power lines, power plants, and other places. In the acceptance of new construction projects, testing after major repairs, and troubleshooting, insulation performance judgment can be quickly completed. It has the advantages of short testing time, high safety, and minimal damage to equipment, and is an indispensable standard equipment for high-voltage testing sites.