Series resonant variable frequency test device, also known as variable frequency series resonant AC withstand voltage test device, is a professional instrument specially used for AC withstand voltage tests on capacitive electrical equipment with large capacity and high voltage. It is widely used in electric power, metallurgy, petroleum, chemical and other industries.



⚙️ Working Principle

The core of the device is based on the principle of series resonance. Simply put, it uses a power supply with adjustable frequency to excite a series circuit composed of a high-voltage reactor (inductance L) and the test object (capacitance C).

By adjusting the output frequency of the frequency converter controller, when the inductive reactance and capacitive reactance in the circuit are equal, series resonance occurs in the circuit. At this time, the power supply only needs to provide a small input power to generate a very high test voltage on the test object, thereby meeting the requirements of the withstand voltage test.