The variable frequency series resonance test device operates on the principle of series resonance. It uses an excitation transformer to stimulate the series resonance circuit and adjusts the output frequency of the frequency converter controller to achieve series resonance between the circuit inductance L and the test object capacitance C. The resonance voltage is then applied to the test object. Variable frequency resonance test devices are widely used in industries such as power, metallurgy, petroleum, and chemical engineering, and are suitable for acceptance and preventive tests of high-capacity, high-voltage capacitive test objects.

 

  The BPXZ series resonance withstand voltage device mainly consists of a frequency converter controller, excitation transformer, high-voltage reactor, and high-voltage divider. Frequency converter controllers are divided into two categories: those with 20KW and above are control desk type, and those below 20KW are portable box type; they consist of a controller and a filter. The main function of the frequency converter controller is to convert a fixed amplitude and frequency 380V or 200V industrial frequency sinusoidal AC power into a sinusoidal wave with adjustable amplitude and frequency. It also provides power for the entire set of equipment. The excitation transformer boosts the output voltage of the frequency conversion power supply to a suitable test voltage. The high-voltage reactor L is an important component of the resonance circuit. When the power supply frequency equals 1/(2π√LCX), it forms a series resonance with the test object CX.