The series resonance formed by the reactor L and the test object capacitance C has a fixed resonant frequency F=1/(2π√L•C). When the test frequency equals this frequency, the circuit resonates.
Based on this principle, the frequency conversion power supply provides power to the excitation transformer, which transforms it into medium voltage and applies it to L and the test object capacitance C. By changing the output frequency of the frequency conversion power supply, the circuit is brought into a series resonance state, and then the output voltage of the frequency conversion power supply is adjusted so that the voltage on the test object reaches the required value.
