The high voltage switch operating voltage test (commonly known as «low voltage test») is a basic preventive electrical test to ensure the safe operation of the high voltage circuit breaker of the power system. At present, the power sector basically uses the following two methods to test:

1. Use the DC system of the field control cabinet as the test power supply, and test the voltage by the sliding line varistor. The biggest drawback of this method is that if the field test wiring is short-circuited or DC direct grounding, it will directly affect the entire DC system. If it is light, the high-voltage equipment on the site will be lost, and the DC system will collapse.

2. Using on-site AC power, using a voltage regulator for simple silicon rectification and direct output DC, the disadvantages of this method are:

①The regulator is heavy, inconvenient to use, and the output DC ripple is large.

②The input and output are not isolated, and the casing may be charged, endangering personal safety.

In view of the above situation, our company has developed a new generation of high-voltage switch closing power supply, providing test power supply for on-site high-voltage switch and opening and closing operation test, avoiding direct use of DC system in the field control box, effectively preventing possible on-site The hazards created by the DC system provide conditions for the safe operation of field devices.