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ZXGXZ Resonant AC Withstand Voltage TestSystem forGenerators: TechnicalOverview
The ZXGXZ Resonant Test System is a specialized solution designed for conducting AC withstand voltage tests on generators. According to national standards, power frequency withstand voltage tests should be performed within 45Hz–65Hz. However, field testing of generators often requires stricter frequency control at 50Hz ± 2Hz. Given the large capacitance of generator stator windings, conventional resonant transformers are often used but are bulky and inconvenient for on-site applications. The ZXGXZ system employs a frequency-modulated series resonant design to overcome these limitations, offering a portable, efficient, and safe alternative for field testing.
System Features
1.High Efficiency & Compact Design
The system utilizes full reactive power compensation, meaning the input power supply capacity is less than 1/10 of the test load. This results in a significantly smaller and lighter system compared to conventional test sets of the same capacity.
2.Low Distortion Output
The series resonant circuit acts as a harmonic filter, ensuring that the output voltage waveform is nearly sinusoidal with total harmonic distortion (THD) below 1%, providing higher accuracy and reliability in testing.
3.Inherent Safety During Breakdown
In the event of a flashover or breakdown, the fault current is limited to less than 1/10 of the pre-fault test current (depending on the system’s quality factor, Q). This prevents extensive damage to the test object and enhances operational safety.
4.Automatic Arc Suppression & Voltage Recovery
The system is designed to automatically extinguish arcs after a flashover and allows for stable and gradual recovery of the resonant voltage, ensuring safe and controlled test conditions.
Technical Specifications
Parameter | Specification |
Rated Output Voltage | 0–60 kV AC (RMS) |
Output Frequency | 50 Hz |
Voltage Waveform | Sine wave, THD ≤ 1% |
Operating Mode | Continuous at full power for 1 minute |
Quality Factor (Q) | 10–40 |
Maximum Test Capacity | ≤ 3000 kVA |
Power Supply Input | 380 V ± 15%, 50 Hz |
Product Series & Applications
The ZXGXZ system is modular and can be configured based on the test object’s capacitance and voltage requirements.
Model | Control Cabinet | Reactor Configuration | Excitation Transformer | Divider | Application Range |
ZXGXZ-100/50 | 10 kW / 220 V | 50 kV / 1 A × 2 sets | 10 kW / 5 kV | 50 kV / 500 pF | Generator: 0.07–0.13 µF, 10 kV cable ≤ 1.0 km |
ZXGXZ-150/50 | 15 kW / 380 V | 50 kV / 1.5 A × 2 sets | 15 kW / 5 kV | – | Generator: 0.13–2 µF, 10 kV cable ≤ 1.5 km |
ZXGXZ-225/50 | 25 kW / 380 V | 50 kV / 1.5 A × 3 sets | 25 kW / 5 kV | – | Generator: 0.2–0.27 µF, 10 kV cable ≤ 2.5 km |
ZXGXZ-350/50 | 30 kW / 380 V | 60 kV / 2 A × 3 sets | 30 kW / 5 kV | – | Generator: 0.27–0.33 µF |
Note: System configuration should be customized based on the actual capacitance of the equipment under test.
Reference: Typical Generator Capacitance Values
The following table lists typical phase capacitance values for various generators, which is essential for selecting the appropriate test system configuration.
Category | Generator Model | Rated Capacity (MW) | Rated Voltage (kV) | Phase Capacitance (µF) |
Thermal Power | TQN-50-2 | 50 | 10.5 | 0.209 |
QFSN-300-2 | 300 | 18 | 0.18–0.20 | |
QFSN-600-2 | 600 | 20 | 0.234 | |
TBB-800-2 | 800 | 24 | 0.25 | |
ABB 50WT23E-138 | 600 | 22 | 0.253 | |
Synchronous Condenser | TT-30-6 | 30 | 10.5 | 0.20 |
Conclusion
The ZXGXZ Resonant Test System offers a technically advanced, safe, and field-practical solution for AC withstand voltage testing of generators. Its modular design, high efficiency, and excellent safety features make it suitable for a wide range of generator types and ratings. Engineers are advised to verify the specific capacitance of the generator under test and select the appropriate system configuration to ensure accurate and reliable test results.
GDZX is a manufacturer of power detection equipment, offering a diverse range of products with comprehensive models and providing professional technical support. Contact us at +86-27-6552607 or +86-17396104357.Website: http://en.gdzxdl.com/
