By hvhipot 
The research on frequency conversion series resonance (also known as series resonance) structure test and detection device can mainly focus on the design and manufacturing of withstand voltage test systems for 35kV, 10kV cables, 10.5kV thermal generators, and 110kV main transformer neutral points. It has a wide range and is an ideal voltage resistant equipment for city, county, and high-voltage testing electrical installation, maintenance, and testing engineering units. Widely used in industries such as power, metallurgy, petroleum, and chemical in China, it can not only handle various specifications of XLPE and other power system cables GIS、 Circuit breakers and bushings can undergo information exchange withstand voltage tests, and can also be used to detect a large generator through HV Hipot Electric Co., Ltd. certain frequency limitations.
The series resonance control device applies the working principle of knowledge series resonance to generate resonant voltage signals that affect the test sample in the circuit. Series resonance devices are mainly divided into two categories: variable frequency and inductive. They adjust the output frequency of the variable frequency series resonance or adjust the inductance of the adjustable reactor to make the inductance L in the circuit resonate in series with the test sample C.
The series resonance test detection device can be divided into system frequency modulation and induction modulation. It is generally composed of a variable frequency control power supply, excitation transformer, reactor, and capacitive voltage divider. The capacitor and reactor of the sample form a series resonant connection, and the voltage divider is connected in parallel with the sample to measure the resonant voltage on the sample and generate an overvoltage protection signal.
In a series circuit composed of resistors, inductors, and capacitors, when the capacitive reactance XC is equal to the inductive reactance XL, i.e. XC=XL, the phase of the voltage u and current i in the circuit are the same, and the circuit design presents a resistive behavior. This social phenomenon is called series system resonance. When a series resonance occurs in the circuit structure, the impedance of the circuit Z=√ R ^ 2+(XC-XL) ^ 2=R, the total impedance in the circuit is small, and the current will reach a large value.