Basic principle ofseries resonance test device

The series resonance test device usually includes a frequency modulation power supply, a resonant reactor, an excitation transformer, and a voltage divider, among which the series resonance circuit is composed of a capacitor and a resonant reactor. The capacitor voltage divider is connected in parallel with the test object to measure its resonant voltage value, and is also used for overvoltage protection signal; The frequency and voltage regulation power is coupled to the series resonant circuit through an excitation transformer to provide excitation power for it.

Operation method ofseries resonance test device

Before the experiment, the test voltage should be determined based on the test sample, and the capacitance of the test sample should be measured or consulted to determine its capacitance. Then select the appropriate parameters (inductance, rated current, rated voltage) and quantity of resonant reactors for testing and wiring.  

(1) Complete the discharge and grounding operation of the test sample. Ensure that there are no external leads and take various safety protection measures.

(2) Measure the insulation resistance of the test sample properly. Ensure that its resistance meets the requirements.  

(3) Scientifically arrange experimental equipment to ensure stable installation of resonant reactors. Simultaneously, ensure proper grounding of the relevant equipment.  

(4) Connect the circuit according to the drawing, and check the wiring, voltage divider gear, and test power capacity. First, close the test power switch. Next, close the frequency conversion power supply and working power switch. Close the main circuit switch of the variable frequency power supply after the work is stable. The protection voltage is usually between 1.1-1.2 times the test voltage.

(5) Uniformly boost the voltage according to the prescribed boost speed standard. Adjust the voltage adjustment knob so that the output voltage value is between 3% and 5% of the test voltage value, in order to control the system frequency. And observe and record the excitation voltage value and test voltage value. If the condition of minimum excitation voltage and maximum test voltage is met. The frequency at this point is the resonant frequency of the system.

(6) After resonance occurs, adjust the voltage according to the requirements to meet the test voltage requirements. During the period, monitor the high-voltage circuit to ensure that there are no abnormalities in the test sample, and reset the voltage to zero after reaching the specified test time. Cut off the switches of the main circuit, control circuit, and power supply again. Cut off the test power switch, complete the discharge work, and end the test.