Operating Conditions
The equipment is designed for reliable operation under the following environmental conditions:
- Ambient temperature: -15°C to +40°C
- Relative humidity: ≤90% RH (non-condensing)
- Installation altitude: up to 3500 m above sea level
Application Range
This AC resonant test system is suitable for insulation withstand voltage testing of various high-voltage electrical assets.
Power Cable Testing
- Suitable for 10kV, 300mm² power cables up to 3 km in length, with capacitance not exceeding 1.11μF. Test frequency range: 30–300Hz. Maximum test voltage: 22kV.
- Suitable for 35kV, 300mm² power cables up to 1 km in length, with capacitance not exceeding 0.1945μF. Test frequency range: 30–300Hz. Maximum test voltage: 52kV.
- Suitable for 110kV, 300mm² power cables up to 200 m in length, with capacitance not exceeding 0.0294μF. Test frequency range: 30–300Hz. Maximum test voltage: 128kV.
Transformer Testing
- Applicable to transformers rated up to 120MVA / 110kV with capacitance below 0.02μF. Test frequency range: 45–65Hz. Maximum test voltage: 160kV.
GIS and Substation Equipment Testing
- Suitable for AC withstand voltage testing of 110kV GIS systems, busbars, and switchyard equipment. Test frequency range: 30–300Hz. Maximum test voltage: 265kV.
System Technical Specifications
| Item | Specification |
|---|---|
| Rated Output Voltage | 0–270kV |
| Voltage Waveform | Pure sine wave |
| Waveform Distortion | <1.0% |
| Maximum Test Current | 1A |
| Rated Capacity | 270kVA |
| Output Frequency | 30–300Hz |
| Continuous Operating Time | 60 minutes at rated output |
| Quality Factor (Q) | 30–90 |
| Input Power Supply | Single-phase 220V or three-phase 380V ±5%, 50Hz |
| Operating Temperature | -15°C to +40°C |
| Relative Humidity | <90% RH |
| Altitude | <3500m |
| Noise Level | ≤50dB |
Key System Features
The complete test system is independently developed and manufactured, including the variable frequency power supply, excitation transformer, cast-resin resonant reactors, and high-precision capacitive voltage divider.
The control system supports both manual and automatic testing modes, featuring a large-screen display, parameter setting functions, automatic timing, and operation guidance.
Comprehensive protection mechanisms are integrated, including:
- Overvoltage protection
- Overcurrent protection
- Flashover and discharge protection
- Resonance detuning protection
- Zero-start interlock protection
- Power interruption protection
These functions ensure safe operation and reliable testing performance.
System Capacity Design
The system is optimized for AC withstand voltage testing of 110kV power cables up to 200m in length.
Design parameters:
- Test voltage: 128kV
- Test frequency: 75Hz
- Cable capacitance: 0.0294μF
- Calculated test current: approximately 1.8A
- Required inductance: approximately 150H
The system utilizes six resonant reactors arranged as two parallel groups, each containing three reactors connected in series.
Single reactor parameters:
- Rated voltage: 45kV
- Rated current: 1A
- Rated capacity: 45kVA
- Inductance: 100H
Total system capacity:
270kVA / 270kV
Test Configuration Guide
| Test Object | Configuration |
|---|---|
| 10kV Cable (<500m) | 1 reactor |
| 10kV Cable (500–1000m) | 2 reactors in parallel |
| 10kV Cable (1000–1500m) | 3 reactors in parallel |
| 10kV Cable (1500–2000m) | 4 reactors in parallel |
| 10kV Cable (2000–2500m) | 5 reactors in parallel |
| 10kV Cable (2500–3000m) | 6 reactors in parallel |
| 35kV Cable (<330m) | 2 reactors in series |
| 35kV Cable (330–660m) | Two groups of 2 reactors in series connected in parallel |
| 35kV Cable (660–1000m) | Three groups of 2 reactors in series connected in parallel |
| 110kV Cable (200m) | Two groups of 3 reactors in series connected in parallel |
| Transformer ≤120MVA/110kV | 4 reactors in series |
| 110kV GIS / Substation Equipment | 6 reactors in series |
