EN
GDTL-120kVA/40kV Generator Special Power Frequency Resonant Test System
GDTL-120kVA/40kV Digital Intelligent Power Frequency Inductance-Tuned Resonant Withstand Voltage Test System for Generators (120kVA, 0-40kV AC) with 15H-60H Continuously Adjustable Dry-Type Reactor, Pure 50Hz±0.5% Output, ≤0.5% Waveform Distortion, Electric Automatic Tuning, 7-inch Touch Screen, Comprehensive Protection, for 10kV/35kV Generator Stator Winding AC Withstand Voltage Test.
- Description
- Specifications
- Applications
- Advantages
- FAQ
- Recommended Products
Description
The GDTL-120kVA/40kV is a professional, field-optimized power frequency inductance-tuned resonant test systemexclusively designed for AC withstand voltage tests of 10kV and 35kV generator stator windings. 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 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 the frequency-dependent insulation stress differences that can cause misjudgment in generator tests. The system consists of a digital intelligent control box, excitation transformer, 15H-60H continuously adjustable dry-type epoxy-cast reactor, and a 0.5 grade standard capacitor voltage divider. Equipped with an electric servo tuning system and advanced automatic resonance finding algorithm, it can automatically adjust the reactor inductance to match the generator stator capacitance (0.1μF-0.5μF) and achieve resonance within 60 seconds. With comprehensive safety protection and 30-minute continuous operation capability, it ensures accurate and safe generator insulation tests in both power plants and field environments.
Specifications
| Parameter | Specification |
|---|---|
| Input Power | 3-phase 380V±10%, 50Hz |
| Rated Output Capacity | 120kVA |
| Rated Output Voltage | 0–40kV AC (RMS) |
| Rated Output Current | 3A |
| Output Frequency | Fixed 50Hz±0.5% (pure power frequency) |
| Output Waveform Distortion (THD) | ≤0.5% |
| Reactor Type | Dry-type epoxy-cast adjustable reactor (air gap) |
| Inductance Adjustment Range | 15H–60H (continuous stepless) |
| Adjustment Method | Electric servo motor drive |
| Matching Generator Stator Capacitance | 0.1μF–0.5μF |
| System Quality Factor (Q) | ≥30 (typical 30–40) |
| Voltage Measurement Accuracy | ≤±1.5% F.S |
| Current Measurement Accuracy | ≤±1.5% F.S |
| Test Modes | Automatic generator test, Manual test, Timed withstand |
| Timing Range | 0–9999s adjustable |
| Display | 7-inch color touch screen |
| Data Storage | 1000 groups (with time stamp) |
| Data Export | USB flash drive |
| Protection Functions | Zero-start, Over-voltage, Over-current, Flashover, Emergency stop, Ground detection, Over-temperature |
| Continuous Operation Time | 30 minutes at full load |
| Operating Temperature | -10℃ ~ +40℃ |
| Operating Humidity | ≤85%RH (non-condensing) |
| 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 (10kV/35kV Generators)
- Generator stator windings: 10kV/35kV synchronous generators (below 100MW) AC withstand voltage test
- Generator excitation windings: rotor winding insulation test
- Power transformers: 35kV and below power transformers insulation test
- XLPE power cables: 35kV and below medium-voltage power cables test
- Switchgear & GIS: 35kV and below medium-voltage switchgear insulation test
- Bushings & insulators: 35kV and below high-voltage insulators and bushings test
Typical Usage Scenarios
- Power plant commissioning: new generator acceptance tests according to GB 50150-2016
- Preventive maintenance: periodic generator stator winding insulation test
- Generator overhaul: post-overhaul insulation verification
- Third-party inspection: compliance testing and certification
- Construction site testing: on-site test of newly installed generators
Advantages
Pure 50Hz Power Frequency Output
Identical to grid frequency, no frequency-dependent insulation stress → fully complies with GB 50150-2016 generator test requirements
≤0.5% Ultra-Low Waveform Distortion
Excellent waveform quality ensures accurate test results → eliminates harmonic-induced misjudgment of generator insulation
30-Minute Continuous Operation
Meets the long-duration test requirements of generator stator windings → ensures complete insulation assessment
Safe Breakdown Protection
Short-circuit current after breakdown is only 1/Q of test current → prevents expensive generator 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
15H-60H continuous adjustment matches all 10kV/35kV generators below 100MW → one system covers most generator models
FAQ
Q: Why can't variable frequency resonant systems be used for generator stator tests?
A: Generator stator insulation is designed for 50Hz power frequency operation. Variable frequency tests (30-300Hz) change the dielectric loss and electric field distribution in the insulation, leading to inaccurate test results and potential misjudgment. GB 50150-2016 explicitly requires generator AC withstand voltage tests to be performed at power frequency (50Hz).
Q: What is the difference between GDTL-120kVA/40kV (generator) and GDTF-162/54 (cable)?
A:
- GDTL-120kVA/40kV (generator): Pure 50Hz output, ≤0.5% THD, 30-minute continuous operation, optimized for generator stator winding tests
- GDTF-162/54 (cable): Variable frequency output (30-300Hz), ≤1% THD, 60-minute continuous operation, optimized for long cable tests Both use the series resonance principle but are designed for different test objects.
Q: What generator models can this system test?
A: It can test all 10kV and 35kV synchronous generators below 100MW with stator capacitance between 0.1μF and 0.5μF, which covers more than 90% of small and medium-sized generators in operation worldwide.
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 generator in the matching range.
Q: What happens if the generator insulation 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 <0.1A), which effectively prevents further damage to the generator stator winding.
