EN
GDTL-600kVA/50kV High-Capacity Power Frequency Resonant Test System
GDTL-600kVA/50kV Digital Intelligent Power Frequency Inductance-Tuned Resonant Withstand Voltage Test System (600kVA, 0-50kV AC) with 10H-45H Continuously Adjustable Dry-Type Reactor, Pure 50Hz±0.5% Output, ≤0.5% Waveform Distortion, Electric Automatic Tuning, 7-inch Touch Screen, Comprehensive Protection, for 200MW Generator, Large Transformer, 35kV GIS, Long XLPE Cable AC Withstand Voltage Test.
- Description
- Specifications
- Applications
- Advantages
- FAQ
- Recommended Products
Description
The GDTL-600kVA/50kV is a high-capacity, general-purpose power frequency inductance-tuned resonant test system designed for AC withstand voltage tests of large capacitive electrical equipment. It fully complies with GB 50150-2016《Standard for Acceptance Test of Electrical Installation Engineering》 and DL/T 849.6-2016 standards, adopting the series resonance principle to generate high voltage and large current with only a small input power, while maintaining a pure 50Hz sine wave output identical to the grid frequency.
Unlike variable frequency resonant systems, this device adjusts reactor inductance to achieve resonance at fixed 50Hz, completely eliminating frequency-dependent insulation stress differences that can cause misjudgment in generator and transformer tests. The system consists of a digital intelligent control box, excitation transformer (5kV/6kV dual tap), 10H-45H continuously adjustable dry-type epoxy-cast reactor, optional compensating capacitor, and a 0.5 grade standard capacitor voltage divider (1000:1 ratio). Equipped with an electric servo tuning system and advanced automatic resonance finding algorithm, it can automatically adjust the reactor inductance to match test sample capacitances (0.1μF-0.5μF) and achieve resonance within 60 seconds. With 30-minute continuous full-load operation capability and comprehensive safety protection, it ensures accurate and reliable insulation tests in both power plants and substations.
Specifications
| Parameter | Specification |
|---|---|
| Input Power | 3-phase 380V±10%, 50Hz |
| Rated Output Capacity | 600kVA |
| Rated Output Voltage | 0–50kV AC (RMS) |
| Rated Output Current | 12A |
| Output Frequency | Fixed 50Hz±0.5% (pure power frequency) |
| Output Waveform Distortion (THD) | ≤0.5% |
| Reactor Type | Dry-type epoxy-cast adjustable reactor (precision air gap) |
| Inductance Adjustment Range | 10H–45H (continuous stepless) |
| Adjustment Method | Electric servo motor drive |
| Matching Test Sample Capacitance | 0.1μF–0.5μF |
| System Quality Factor (Q) | ≥30 (typical 30–45) |
| Voltage Measurement Accuracy | ≤±1.5% F.S |
| Current Measurement Accuracy | ≤±1.5% F.S |
| Test Modes | Automatic test, Manual test, Timed withstand, Step boost |
| Timing Range | 0–9999s adjustable |
| Display | 7-inch color touch screen |
| Data Storage | 1000 groups (with time stamp) |
| Data Export | USB flash drive, PDF report generation |
| Remote Control | Optional 100m wireless remote control |
| Protection Functions | Zero-start, Over-voltage, Over-current, Flashover, Emergency stop, Ground detection, Over-temperature, Interlock |
| Continuous Operation Time | 30 minutes at full load |
| Operating Temperature | -10℃ ~ +40℃ |
| Operating Humidity | ≤85%RH (non-condensing) |
| Altitude | ≤3000m |
| Compliance | GB 50150-2016, DL/T 849.6-2016, GB/T 16927.1-2011, IEC 60060-1, IEC 61010-1 CAT III 1000V |
Applications
Core Test Objects
- Generator stator windings: 35kV/10kV synchronous generators (up to 200MW) AC withstand voltage test
- Power transformers: 35kV/110kV large-capacity power transformers and autotransformers
- GIS & gas-insulated switchgear: 35kV large-scale GIS, circuit breakers, disconnectors, busbars
- XLPE power cables: 35kV/300mm² cables ≤2km, 10kV/300mm² cables ≤6km
- Capacitor Voltage Transformers (CVT): 35kV/110kV CVT calibration and withstand test
- Bushings & insulators: 35kV/110kV transformer bushings, post insulators, suspension insulators
Typical Usage Scenarios
- Power plant commissioning: new generator and transformer acceptance tests according to GB 50150-2016
- Substation commissioning: 35kV/110kV substation equipment acceptance tests
- Preventive maintenance: periodic insulation strength tests of power equipment
- Generator overhaul: post-overhaul insulation verification
- Third-party inspection: compliance testing and certification
- Factory type tests: manufacturer factory acceptance tests (FAT)
Advantages
Pure 50Hz Power Frequency Output
Identical to grid frequency, no frequency-dependent insulation stress → fully complies with GB 50150-2016 requirements for all electrical equipment
≤0.5% Ultra-Low Waveform Distortion
Excellent waveform quality ensures accurate test results → eliminates harmonic-induced misjudgment of insulation condition
30-Minute Continuous Full-Load Operation
Meets the long-duration test requirements of generators and transformers → ensures complete insulation assessment
Safe Breakdown Protection
Short-circuit current after breakdown is only 1/Q of test current → prevents expensive equipment damage during test
Electric Automatic Tuning
One-click auto tuning finds resonance point within 60 seconds → eliminates manual tuning, improves test efficiency
Wide Inductance Adjustment Range
10H-45H continuous adjustment matches a wide range of test sample capacitances → one system covers generators, transformers, GIS, and cables
97% Energy Saving vs Traditional Test Transformers
Series resonance principle reduces input power to only 1/Q of output power → small input power, light weight, easy to transport
FAQ
Q: What is the difference between GDTL-600kVA/50kV and GDTL-120kVA/40kV?
A:
- GDTL-600kVA/50kV: 50kV peak output, 600kVA capacity, 12A rated current, 10H-45H inductance range, tests up to 200MW generators and 2km 35kV cables, suitable for large power plants and substations
- GDTL-120kVA/40kV: 40kV peak output, 120kVA capacity, 3A rated current, 15H-60H inductance range, tests up to 100MW generators and 1.5km 35kV cables, suitable for medium-sized power plants Both use pure power frequency inductance-tuned resonance technology.
Q: Why is pure 50Hz output important for generator and transformer tests?
A: Generator and transformer insulation is designed for 50Hz power frequency operation. Variable frequency tests change the dielectric loss and electric field distribution in the insulation, leading to inaccurate test results and potential misjudgment. GB 50150-2016 explicitly requires AC withstand voltage tests for generators and transformers to be performed at power frequency (50Hz).
Q: What is the maximum length of 35kV XLPE cable that can be tested?
A: With 12A rated current at 50kV, it can test up to 2km of 35kV/300mm² XLPE power cable or 6km of 10kV/300mm² XLPE power cable.
Q: How long does it take to find the resonance point?
A: The electric automatic tuning system can find the precise resonance point at 50Hz within 60 seconds for any test sample in the matching range.
Q: What happens if the test sample breaks down during the test?
A: When breakdown occurs, the system immediately loses resonance, and the short-circuit current is only 1/Q of the test current (typically <0.4A), which effectively prevents further damage to the test sample.
