HMCXZ AC Resonant Test System

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AC Resonant test system is mainly used for conducting the on-site AC dielectric test for electric equipment with large capacity, including medium-low voltage, high voltage and ultra-high voltage XLPE, GIS, motor stator, large-sized transformer and electric capacitor.
The series variable frequency resonant system is to change the system inductance and test frequency to make circuit in resonant condition. Its electric circuit is shown in Fig.1. The adoption of variable frequency resonant technology reduces the capacity of power source and the weight of equipment, which facilitates on-site test.
 

Features

1. The required power supply capacity is greatly reduced. The series resonant power supply uses the resonant reactor and the capacitor resonance to generate high voltage and large current. In the whole system, the power supply only needs to provide the part of the system that consumes power. Therefore, the power required for the test is only 1/Q of the test capacity.
2. The weight and volume of the equipment is greatly reduced. In the series resonant power supply, not only the bulky high-power voltage regulating device and the ordinary high-power power frequency test transformer are omitted, but also the resonant excitation power supply only needs to test the capacity of 1/Q, so that the weight and volume of the system are greatly reduced, generally 1/10-1/30 of the common test device.
3. Improve the waveform of the output voltage. The resonant power supply is a resonant filter circuit, which can improve the waveform distortion of the output voltage and obtain a good sinusoidal waveform, effectively preventing the harmonic breakdown of the testing sample from being accidentally broken.
4. Prevent large short-circuit currents from burning the point of failure. In the series resonance state, when the insulation weak point of the sample is broken, the circuit is immediately detuned, and the loop current rapidly drops to 1/Q of the normal test current. When the parallel resonance or test transformer method is used for the withstand voltage test, the breakdown current immediately rises several tens of times. Compared with the two, the short-circuit current and the breakdown current are hundreds of times different. Therefore, series resonance can effectively find the insulation weakness, and there is no big short-circuit current burn failure point.
5. No recovery over voltage will occur. When the testing sample breaks down, the high voltage also disappears immediately due to the loss of the resonance condition, the arc is extinguished immediately, and the recovery voltage is re-established for a long time. It is easy to disconnect the power supply before reaching the flash voltage again. This voltage recovery  is an intermittent oscillation process of energy accumulation,  and the process is long,  no recovery over voltage occurs.

Parameter

1. Rated Capacity:20-20000 kVA; 
2. Output Voltage: 0-1000 kV; 
3. Output frequency: 30-300Hz; 
4. Input Power: 220V/380V ± 10 % single phase, 50Hz;
5. Waveform distortion rate: output voltage distortion ≤1 %
6. Working time: 30mins under rated load; 
7. Cable testing: continuous 60 minutes under rated load
8. Temperature rise: <65Kunder rated load
9. Working Temperature: -15℃~+45℃; 
10. Accuracy: RMS 1.5

It can be customized according to testing requirements .
 

Pictures