Series resonance is widely used in electric power, metallurgy, petroleum, chemical and other industries, suitable for large capacity, high voltage capacitive test piece of handover and preventive test. Portable frequency series resonance device is mainly used in the following aspects:
1, 6kV-500kV high-voltage crosslinked cable AC voltage withstand test
2, AC voltage withstand test of generator
3, AC voltage withstand test of GIS and SF6 switch
4, 6kV-500kV transformer frequency withstand voltage test
5, other electric power high-voltage equipment such as busbar, casing, transformer AC voltage withstand test.
Expanded information:
Serial resonance test device is divided into frequency modulation and inductance modulation. Generally it is composed of frequency conversion power supply, excitation transformer, reactor and capacitance divider. The capacitance of the test piece and the reactor constitute a series resonance connection; voltage divider is connected in parallel on the test piece, used to measure the resonance voltage on the test piece, and for over-voltage protection signal.
In the series circuit composed of resistance, inductance and capacitance, when the capacitive reactance XC and inductive reactance XL are equal, that is, XC = XL, the circuit voltage u and current i are in the same phase, the circuit shows resistive, this phenomenon is called series resonance. When the circuit occurs series resonance circuit impedance Z = √R^2 + (XC-XL)^2 = R, the total impedance in the circuit is minimum, the current will reach the maximum value.
Baidu Encyclopedia - Series Resonance