180kVA/60kV Series Resonance Withstand Voltage Test Device Overview:
Variable frequency series resonance is suitable for AC withstand voltage tests of various large power transformers, power cables, steam and hydro generators, and other capacitive equipment, which must be strictly conducted periodically according to test regulations. Under power frequency conditions, due to the large capacitance of the test object or the high test voltage requirements, the power capacity of the test device is correspondingly high. Traditional power frequency withstand voltage devices often have large single-piece volume, heavy weight, are inconvenient for on-site handling, and are not easy to combine arbitrarily, resulting in poor flexibility.
JY-180kVA/60kV Series Resonance Withstand Voltage Test Device Technical Solution
1. Basic Principle of Variable Frequency Series Resonance:
The variable frequency series resonance withstand voltage test uses the inductance of the reactor and the capacitance of the test object to form an LC series circuit. By adjusting the output voltage frequency of the variable frequency power supply, series and parallel resonance is achieved, obtaining high voltage on the test object. This is a new method for high voltage testing, highly praised by experts, and has been widely used domestically and internationally.
2. Characteristics of the Variable Frequency Series Resonance Test Device:
The variable frequency series resonance test device has large output capacity, high output voltage, and can arbitrarily combine reactors for AC withstand voltage tests on different test objects.
The variable frequency series resonance test device is small in size and light in weight, with each piece weighing no more than 50kg, making it especially convenient for field tests.
The variable frequency series resonance test device has good protection functions, including overvoltage protection, overcurrent protection, time protection, flashover protection, overtemperature protection, and module protection.
The variable frequency series resonance test device is extremely simple to operate and has both manual and automatic modes.
The variable frequency series resonance test device uses a large screen, making test data clear at a glance, and can print test results.
The variable frequency series resonance test device has no risk of overvoltage after test object breakdown, causing minimal damage to the test object.
The power capacity required for the variable frequency series resonance test device is small, only a fraction of that required for power frequency transformer tests, solving the problem of difficulty in finding a power source on site.
3. Scope of Application:
Suitable for AC withstand voltage tests of 400mm2/35kV cross-linked cables with a length of 2000m.
4. Operating Environmental Conditions:
1 Ambient temperature: -10℃ to 40℃
2 Relative humidity: not more than 90%
3 Altitude: below 2500 meters
5. Standards Referenced and Implemented for Equipment Manufacturing
1 DL/T849.6—2004 High voltage resonant test devices;
2 GB 6450—1986 Dry-type power transformers;
3 DL/T848.2—2004 Test transformers;
4 GB/10229—1988 Reactors;
5 GB/T11920—1989 General technical conditions for control devices;
6 GB/T16927.1—1997 High voltage test techniques;
7 IEC358—1990 Coupling capacitors and capacitor dividers.
6. Equipment Configuration List
Name
|
Specification/Model
|
Unit
|
Quantity
|
Dimensions (mm)
|
Weight (kg)
|
Variable Frequency Power Supply
|
15kVA
|
Unit
|
1
|
420×280×380
|
22
|
Excitation Transformer
|
15kVA/2.5kV×2
|
Unit
|
1
|
450×300×650
|
75
|
High Voltage Reactor
|
25kV/3A//40H
|
Unit
|
4
|
φ330×470
|
(each)65
|
Capacitive Voltage Divider
|
50kV/0.001uF
|
Unit
|
1
|
φ150×750
|
8
|
Compensation Capacitor
|
50kV/0.0125uF
|
Unit
|
1
|
φ250×750
|
18
|
Accessories
|
|
Set
|
1
|
|
|
7. Main Functions and Parameters:
7.1 System Parameters of the Variable Frequency Resonance Test Device:
7.1.1. Instrument input voltage: 220V±10% 50Hz;
Power input voltage: 380V±10% 50Hz;
7.1.2. Rated output voltage adjustment range: 0 ~ 50kV;
7.1.3. Maximum test capacity: 300kVA;
7.1.4. Resonant voltage waveform: sine wave, distortion rate: ≤0.5%;
7.1.5. Output voltage instability: ≤0.5%;
7.1.6. Output frequency range: 25～320Hz;
7.1.7. Frequency adjustment resolution: 0.01Hz;
7.1.8. Quality factor Q value: not less than 50 under rated load;
7.1.9. Insulation level: withstand voltage of 1.2 times rated voltage for 1 minute;
7.1.10. Continuous operation time at rated current not less than 30 minutes;
7.1.11. Voltage measurement accuracy: Class 1;
7.1.12. Noise: ≤45dB;
7.1.13. The device is equipped with the following protection functions:
The equipment has manual test, automatic tuning, and automatic test;
Overvoltage protection, overcurrent protection, discharge protection, power-off protection, and zero-start protection.
Test data displayed on a large screen, Chinese menu, printable output, and the printer is embedded.
7.2 Variable Frequency Power Supply:
7.2.1. Rated output capacity: 15kVA;
7.2.2. Instrument power: 220V±10% 50Hz;
Power supply: 380V±10% 50Hz;
7.2.3. Rated input current: 39.5A;
7.2.4. Rated output voltage: 0-340V adjustable, single-phase, output voltage instability 0.05%;
7.2.5. Rated output current: 44A;
7.2.6. Frequency adjustment range: 25～320Hz;
7.2.7. Temperature rise under continuous operation at rated capacity within specified working time ≤60K;
7.2.8. Display the following parameters:
a. Frequency, voltage, and current after variable frequency output;
b. Overvoltage protection voltage value, which can be arbitrarily set. When the output voltage of the complete device reaches the protection setting, the complete device can be automatically cut off;
c. Overcurrent protection: When the output current of the variable frequency power supply reaches the protection setting value, the complete device can be automatically cut off;
d. Breakdown protection: When a ground flashover occurs on the high-voltage side, the complete device can be automatically cut off. The device is equipped with an isolation device to ensure that equipment and personnel are not harmed;
e. Has full voltage output protection. During voltage regulation, if voltage regulation loses control, the variable frequency power supply immediately locks;
7.2.9. The following operations can be performed:
a. Frequency adjustment, with coarse and fine adjustment for rising and falling frequency, and automatic search for the test resonance point to ensure that the resonance frequency does not drift during the entire test process;
b. Equipped with setting voltage and setting time. The voltage automatically rises to the set value and stops, and timing starts automatically;
c. Equipped with setting buttons for various protection functions, allowing various protection values to be set on the panel;
d. Equipped with manual test function and automatic test function;
e. Equipped with test data printing function.
7.3 Excitation Transformer
7.3.1. Structure type: dry-type;
7.3.2. Input voltage: 340V;
7.3.3. Output voltage: 2.5kV/5kV;
7.3.4. Rated capacity: 15kVA;
7.3.5. Rated output current: 6A/3A;
7.3.6. Operating frequency: 30～300Hz;
7.3.7. Under continuous operation at rated capacity within specified working time, the temperature rise of the coil to air is not greater than 60K;
7.4 High Voltage Reactor 25kV/3A
7.4.1. Structure type: dry-type, epoxy casting;
7.4.2. Rated capacity: 75kVA;
7.4.3. Rated voltage: 25kV;
7.4.4. Rated current: 3A;
7.4.5. Rated inductance: 40H;
7.4.6. Operating frequency: 30～300Hz;
7.4.7. Under continuous operation at rated capacity within specified working time, the temperature rise of the reactor to air is not greater than 60K;
7.4.8. Performance and characteristics: The reactor is designed as dry-type, epoxy casting, and can be freely and conveniently stacked. The epoxy resin insulating cylinder shell has sufficient electrical and mechanical strength, necessary heat dissipation capability, and margin for oil thermal expansion and contraction. The upper and lower cover plates of the shell are orange-red.
7.5 Capacitive Voltage Divider
7.5.1. Structure type: capacitive;
7.5.2. Rated voltage: 50kV;
7.5.3. Rated capacitance: 1000pF;
7.5.4. Operating frequency: 30～300Hz;
7.5.5. Measurement accuracy: ≤1.0%;
7.5.6. Performance and characteristics:
a. Can operate continuously for 2 hours at rated voltage.
b. Within the range of 30～300Hz, its accuracy and stability remain unchanged.
c. At a temperature of 20℃, the dielectric loss value of the capacitive voltage divider is ≤0.0025
d. Voltage measurement is carried out through a dedicated test lead to the variable frequency power supply.
7.5 Compensation Capacitor
7.5.1. Structure type: capacitive;
7.5.2. Rated voltage: 50kV;
7.5.3. Rated capacitance: 12500pF;
7.5.4. Operating frequency: 30～300Hz;
7.5.6. Working time: can operate continuously for 2 hours at rated voltage.
