What are the components of the complete set of frequency conversion series resonance test equipment?

The variable frequency series resonance test device is composed of a variable frequency power supply, an excitation transformer, a high-voltage reactor and a capacitance voltage divider.

1.Variable frequency power supply: the power supply of 220V, 380V, 50Hz is changed to adjustable frequency and continuously adjustable voltage, and at the same time, it integrates operation, protection, control and monitoring functions.

2.Excitation transformer: Voltage boost the output voltage of the variable frequency power supply, and isolate the high voltage and low voltage at the same time.

3.High-voltage reactor: series resonance with capacitive specimen.

4.Voltage divider: Measure the high voltage value and low voltage on the regulator.

The series resonant withstand voltage test device has five major structural components:

Variable frequency voltage regulation power supply: it can not only change the frequency of the output, but also change the voltage of its output;

Excitation transformer: plays the role of coupling signal and voltage conversion, and increases the voltage according to its own transformation ratio;

Reactor: It is connected in series with the test product to form an LC loop;

Voltage divider: used to measure the voltage on the test product, and at the same time as a sampling signal feedback to the instrument;

Compensation capacitor: used to adjust the frequency of the test product;

1. Main components.

The complete set of variable frequency series resonance test device is composed of variable frequency power supply, excitation transformer, reactor and capacitor voltage divider, as shown in the following figure

2. Resonance accessories.

Reactor equalizing ball, voltage divider equalizing ball, insulating base, air duct, power inlet, high-voltage short wiring, excitation variable incoming line, discharge rod and other accessories, as shown in the following figure:

Power cords and electrical equipment are well insulated. The live parts of lamp heads, sockets, and switches shall not be exposed to prevent electric shock.

It is strictly forbidden to randomly connect the wires to avoid electric shock or **.

Do not stand on wet ground and move live objects to prevent electric shock.

The choice of fuse should be fair. It is strictly forbidden to replace it with copper wire, aluminum wire or iron wire to prevent fire.

Household appliances such as refrigerators, refrigerators, washing machines, etc. It should be equipped with a socket with a grounding wire that meets the requirements of the product.

Check or replace the lamp head. Even if the switch is off, do not touch it directly with your hands to avoid electric shock.

In the event of a fire in an electrical appliance, the power supply should be blocked first, and it is strictly forbidden to use water directly to prevent electric shock. 8. In case of electric shock, the power supply should be disconnected first (such as electric shock from a height, and measures should be taken to prevent the electric shock from falling), and then first aid should be carried out.

The complete set of variable frequency series resonance test device is composed of variable frequency power supply, excitation transformer, high-voltage reactor and capacitance voltage divider; The complete set of frequency conversion series resonance test device adopts the method of adjusting the frequency of the power supply, so that the reactor and the tested capacitor can achieve resonance, and obtain high voltage and high current on the tested product. The capacitance and reactor of the sample are connected in series resonance, the voltage divider is connected in parallel with the sample, and the resonant voltage is measured by the complete set of frequency conversion series resonance test device, and the overvoltage protection signal is issued; The excitation transformer couples the FM power output to a series resonant circuit to provide the excitation power of the series resonant.

The complete set of frequency conversion series resonance test device has a high degree of automation, small size and light weight. The weight of each unit of the complete set of equipment does not exceed 40kg, which is suitable for on-site handling. The reactor adopts dry epoxy casting, which is reliable in operation and easy to handle, and the on-site test does not need to be hoisted, and the installation test can be carried out manually.

Inverter series resonance test equipment is widely used in electric power, metallurgy, petroleum, chemical and other industries.

Functional characteristics of the complete set of frequency conversion series resonance test device:

1. High stability and reliability, the system adopts imported power components as the core of power conversion.

2. The automatic tuning function is powerful, and the frequency sweep curve is displayed between 30 Hz and 300 Hz when the frequency conversion series resonance test system is automatically tuned.

3. Support a variety of test modes, the system supports the test modes of "automatic tuning manual voltage regulation", "automatic tuning automatic voltage regulation" and "manual tuning manual voltage regulation".

4. The system has a friendly human-machine interface, test parameter setting, test control, and equivalent screen display of test results, which is intuitive and clear, and has the functions of automatic timing and operation prompts.

5. The protection function is perfect, and the complete set of frequency conversion series resonance test device has the functions of zero protection, overcurrent protection, overvoltage protection, flashover protection, etc., which ensures the reliability of the system.

Variable frequency series resonance test complete set of device is an indispensable test method for the daily debugging of electrical equipment, and the circuit of the complete set of frequency conversion series resonance test is well used in the withstand voltage test of electrical equipment such as transformers and power cables. This paper mainly introduces the physical application of the circuit of the complete set of variable frequency series resonance test.

1) AC withstand voltage test of power cable, at present, there are more and more XLPE-XLPE insulated power cables at home and abroad to replace the original oil-filled paper insulated power cables. However, there are many problems in the DC withstand voltage test of traditional XLPE cables; Because the cross-linked cable is a large capacitance test, the use of series resonance test method is simple and convenient, and good AC voltage frequency and waveform can be obtained, which has become an ideal test method in the AC withstand voltage test of cross-linked cable.

2) AC withstand voltage test of power transformer, reactor and transformer, the world clearly stipulates that the AC withstand voltage test of power transformer, reactor and transformer can be used to use power frequency voltage test or induced voltage test method, and the test voltage waveform should be as close to sinusoidal as possible. According to this standard, the circuit of the complete set of variable frequency series resonance test device can be tested under any conditions. The device has a wide frequency and voltage range, is highly adaptable to the test object, and can be used with a wide range of voltage levels of test objects.

3) AC withstand voltage test of SF6 closed combiner, AC withstand voltage test is an important method to check the GIS main insulation when SF6 is closed. In most cases, a series resonant test setup is used.

4) AC withstand voltage test of other equipment, for circuit breakers, bushings and other equipment, it is generally required that the withstand voltage test is a power frequency voltage test. If the power frequency test device cannot meet the on-site requirements, the resonant withstand voltage test method can also be used instead. When the resonance withstand voltage test is adopted, the test frequency is higher due to the small capacitance of the device, but the series resonance test device can also use appropriate compensation capacitance to reduce the test frequency, so that the instrument can reach the test frequency close to the power frequency.

Respondent: Huatian Power.