Series Variable Frequency Resonant Test System

The Series Variable Frequency Resonant Test System (also commonly known as Variable Frequency Series Resonant AC Withstand Voltage Test System) is a high-voltage test equipment widely used in the power system. It is mainly used for handover and preventive withstand voltage tests on large-capacity, high-voltage capacitive test objects.

The following is a detailed introduction to the core principles, composition, characteristics, and applications of the device:

⚡️ Working Principle

The device is based on the LC series resonance principle. By adjusting the output frequency of the variable frequency controller, the inductance (L) of the high-voltage reactor in the circuit and the capacitance (C) of the test object undergo series resonance.

When the circuit frequency satisfies the formula f = 1 / (2π√LC), resonance occurs in the circuit. At this time, the voltage obtained on the test object is Q times the output voltage at the high-voltage end of the excitation transformer (Q is the system quality factor, usually reaching dozens to hundreds of times). This means that with a relatively small power input, an extremely high test voltage can be generated on the test object.