Resonant AC Test Systems| Detailed introduction of technical principles

The core testing principle of the resonant test system is series resonance.

The system forms a series resonant circuit through an adjustable reactor and the capacitance of the test object itself. During testing, the power supply output frequency or the reactor inductance is adjusted to bring the circuit to resonance at or near the power frequency. At this point, the total impedance of the circuit is at its minimum, exhibiting pure resistance, and the current is at its maximum.

At the resonant point, the voltage across the reactor is equal in magnitude but opposite in phase to the voltage across the test object's capacitance. The two voltages are superimposed on the test object, generating the required high voltage. The power supply only needs to provide a small amount of active power to compensate for the losses in the circuit resistance, thus maintaining resonance. Therefore, this principle enables highly efficient power frequency withstand voltage testing of large-capacity test objects (such as cables, GIS, and generators) using a small-capacity power supply. Resonant AC Testing System, AC Resonant Test System, Variable Frequency AC Resonant Test System 75kVA 75kV 30-300Hz

This resonant test system is designed and manufactured primarily for AC withstand voltage tests of 10kV and 35kV cables, 10kV and 35kV main transformers, and 35kV switches.

It has a wide range of applications and is an ideal withstand voltage testing device for municipal, county, and prefecture-level high-voltage testing departments, as well as power installation and maintenance engineering units.

The system mainly consists of a variable frequency power supply, excitation transformer, reactor, capacitive voltage divider, and compensation capacitors.

1. 1.5km of 10kV/300mm² cable, capacitance ≤0.563uF, test frequency 30-300Hz, test voltage 22kV, test time 5min

2. 35kV main transformer AC withstand voltage, capacitance ≤0.02uF, test frequency 45-65Hz, test voltage 68kV, test time 1min

1. Features overvoltage, overcurrent, zero-position start, and system detuning (flashover) protection functions.

2. Equipment weight and volume are 1/10-1/30 of ordinary testing equipment. The power required for testing is only 1 Ω of the test capacity.

3. The device has three operating modes: fully automatic mode, manual mode, and automatic tuning and manual voltage boost mode.

4. Data storage and printing; stored data is numbered for easy user identification and retrieval.

5. The frequency starting point can be arbitrarily set within the specified range during automatic frequency sweep.

6. DSP platform technology: Functions can be added, removed, and upgraded according to user needs; the human-machine interface is more user-friendly.

7. Improved output voltage waveform.

8. Prevents large short-circuit currents from burning out fault points.

9. No recovery overvoltage will occur.

MSXB-F-75kVA 75kV Resonant AC Test System, AC Resonance Test System, Variable Frequency AC Resonance Test System