NAGXZ automatic power frequency resonance high voltage complete pressure testing device

NAGXZ automatic power frequency resonance high voltage complete pressure testing device

Also called name

Frequency conversion resonance withstand voltage test device, variable frequency series resonance test device, variable frequency resonance test device, series resonance withstand voltage test device, variable frequency resonant high voltage test device, power frequency resonance test device, DC withstand voltage test, reactor Q value, DC resistance Pressure test standard, series resonance device, series resonance withstand voltage test, high frequency pulse oscillation test, withstand voltage test reactor, series resonance withstand voltage tester, excitation transformer repair

Application range

Power frequency resonance device is mainly used for AC withstand voltage test of 6kV-500kV high voltage cross-linked cable, 6kV-500kV transformer, generator, GIS and SF6 switch, and other high voltage equipment (such as busbar, bushing, transformer). A device that uses a tuning inductor and a load capacitor to generate a power frequency series resonance to obtain a power frequency test voltage. Series resonance test equipment is widely used in electric power, metallurgy, petroleum, chemical and other industries, and is suitable for the handover and preventive tests of large-capacity, high-voltage capacitive samples.

The power frequency resonance has two modes: series resonance and parallel resonance. The compensation effect of the power supply capacity of these two methods is basically the same. After the full compensation, the input capacity can be reduced to less than 1/Q of the test output capacity.

The power frequency resonance test device produced by Nan'ao Electric has been widely used in electric power, metallurgy, petroleum, chemical and other industries, and is suitable for large-capacity, high-voltage capacitive test products, such as generators, transformers, GIS, high-voltage cross-linked cables, Handover test and preventive test of transformers, bushings, etc.

Working principle

The series resonance composed of the reactor L and the capacitor C of the test piece has a fixed resonance frequency F = 1 / (2π √ L · C). When the test frequency is equal to this frequency, the circuit resonates.

Through this principle, the power supply from the FM power supply is sent to the excitation transformer, and the transformer is transformed into a medium voltage plus L and the capacitor C to be tested. By changing the output frequency of the FM power supply, the loop is in series resonance state, and then adjusting the output voltage of the FM power supply to make the voltage on the sample reach the required voltage value.

Mian features

The power frequency resonance test device uses the principle of series resonance. By adjusting the output frequency of the variable frequency controller, the inductance L of the reactor in the loop and the sample capacitor C are series resonant, and the resonant voltage is the voltage applied to the sample.

Our company's self-developed frequency modulation and voltage regulation software technology in the high-voltage test of power frequency resonance test equipment is ahead of the domestic high-voltage test industry. It uses 16-bit fine frequency modulation, 10KHz carrier frequency, SPWM and imported original IPM module. The designed and manufactured power frequency resonance test device fully complies with the national regulations and requirements for high voltage test.

Power Frequency Resonance Characteristics of Nan'ao Electric Production

1. The large screen displays test data, test status and real-time operation step indication function. The test voltage, frequency modulation range and pressurization time can be flexibly set. The test results can calculate the capacitance value of the test object and can be printed.

2. Small size, light weight and convenient operation. Due to the full compensation of resonance and reactive power, the power of the power supply and equipment is only 1/10 or less of the required capacity of the test object (1/Q>10); the volume of the same capacity is small, the weight is light, and the output capacity of the device is large. The power supply capacity is small, the price is low, and the operation is convenient and safe.

3. The series resonance is actually a current filter circuit, so that the current passing through the test object is basically the fundamental current, and the waveform distortion rate (THD) of the output voltage is extremely small, which is superior to all existing AC voltage-resistant devices. The short-circuit current after flashover or breakdown of the sample is only 1/10 or less of the test current before the short-circuit (1/Q), which can effectively prevent damage to the fault point after breakdown; automatically extinguish the arc immediately after flashover, The process of recovering the resonant state voltage after the arc is longer (seconds) is a steady state establishment process, with no voltage overshoot and no danger of recovering overvoltage in the microsecond millisecond transient process.

4, L - the inductance of the adjustable reactor, CX - the capacitance of the test product, r - the active parallel loss of the adjustable reactor and the equivalent parallel resistance of the total loop total loss of the tested device. When L is adjusted to the resonance point inductance L0, XL=XC, IL=IC realizes complete parallel resonance at this time. When parallel resonance, the voltage UX? supplied by the power supply is the same as the test voltage. Since the reactive current is completely compensated and offset, the power supply only needs to provide the integrated active loss of the IX=Ir compensation resonant circuit of COSΦ=1 to excite and maintain stable resonance. . Parallel resonance has the same reactive power compensation as series resonance and its corresponding advantages, but it cannot fully have the other three characteristics of series resonance. In general, series resonant AC withstand voltage is used.

5, high resolution, frequency resolution of 0.01Hz, voltage resolution of 0.01V; high security and reliability, the system has over voltage, over current and discharge protection, to ensure personal and equipment safety.

Main parameters

1, the ambient temperature: -10 ~ 45 ° C

2. Working humidity: ≤90%

3. Altitude: ≤2000M

4, power input: 220V ±10% single-phase output 0 ~ 220V (≤ 10KW)

                    380V±10% three-phase, 50Hz output 0~400V

5, rated test capacity: 0 ~ 8000KVA (can be customized)

6, resonant voltage: 0 ~ 1000kV (can be customized)

7, frequency adjustment range: 0.1 ~ 300Hz

8, system measurement accuracy: 0.5

9, frequency adjustment resolution: 0.01Hz

10. Unstableness: ≤0.05%

11, the output waveform: sine wave

12, waveform distortion rate: ≤ 0.5%

13, the integrated noise value: 60dB

14, reactor Q: 30 ~ 200

NAGXZ series power frequency resonance packing list

Reactor: Connected in series with the test object to form an LC series resonant circuit.

Compensation Capacitor: Compensate the small capacitance test sample to adjust the frequency of the test object.

FM power supply: both change its output frequency and change its output voltage.

Excitation transformer: It acts as a coupling signal and voltage conversion, and increases the voltage according to its own change.

Capacitor voltage divider: measures the voltage on the test object and feeds it back to the FM power supply as a sampling signal.