A newly disclosedseries resonant voltage withstand device (also known as series resonant). The capacitors and reactors of the test object are connected in series resonant connection, the high-voltage discharge device is connected in parallel with the test object, and the output of the variable frequency power supply is coupled to the series resonant circuit through a driving transformer. The lower output voltage of the variable frequency power supply can generate a higher test voltage on the test object through circuit resonance.
technicalfield
This utility model relates to an electric power testing device, particularly to a testing unit that uses the principle of circuit resonance to obtain the required high voltage test.
Background technology
At present, due to the large capacitance of general test specimens or high expectations for test voltage, there are higher requirements for the power supply capacity of test specimens. For traditional industrial grade withstand voltage devices, the single piece volume is often large, and heavy objects are not easy to move on site or combine, resulting in poor operability; The existing improved series resonance testing devices generally achieve system resonance by adjusting the capacitance in the regulator or inductor, but it is not easy to change the capacitance to continuously tune it, and it is not easy to change the inductance to generate voltage waveforms.
content
The present utility model provides a series resonant pressure tester to overcome the shortcomings of the single piece volume of existing industrial frequency withstand voltage devices, which are difficult to combine in any situation and have poor operability. The series resonant pressure tester uses a variable ratio frequency converter power supply to generate a series resonant loop, thereby obtaining a high voltage testing equipment close to the frequency.
The technical solution adopted to solve the technical problem of the present utility model is: the isolation filter type power supply of the series resonant pressure tester is connected to the variable frequency power supply with square wave output, the variable output terminal frequency power supply is connected to the input terminal of the driving transformer, the output terminal of the driving transformer is connected to the input terminal of the high-voltage reactor, and the output terminal and input terminal of the high-voltage reactor are connected to each other. The high-voltage capacitor is composed of a high-voltage arm and a low-voltage arm connected in series, and the low-voltage arm of the high-voltage arm is grounded. The high-voltage arm is isolated from the sampled high-voltage discharge device through a conductor line between the optical fiber and the low-voltage arm, and is connected to each other. The high-voltage discharge device is connected to each other through the variable frequency power supply.
One preferred solution for this scheme is that the high-voltage reactor is composed of multiple reactors connected in series.
During the testing process, the tested product is connected in parallel with a high-voltage capacitor. By adjusting the output frequency of the variable frequency power supply to create a series resonance loop, the output voltage of the variable frequency power supply is adjusted under the condition of loop resonance to test the product voltage again. Due to the resonance in the loop, the output voltage of the variable frequency power supply is small, which can generate a higher test voltage on the tested product.
The beneficial effect of this utility model is that due to the resonance in the loop, the output voltage of the variable frequency power supply can be exactly at a higher test product trial voltage. The interference caused by using an isolated filter type power supply helps to mitigate the impact of external motors or other high-power power sources during the power boosting process; The variable frequency power supply outputs square waves, which is also the main theme of the power supply with high output power; The high-voltage discharge device adopts fiber optic isolation sampling, which can effectively protect the variable frequency power supply when the test product fails.
