Product Introdution
This AC withstand voltage test device is a versatile solution designed for testing cross-linked cables, hydraulic generators, main transformers, busbars, GIS, and other high-voltage equipment. Featuring a frequency conversion control power supply, excitation transformer, reactor, capacitor voltage divider, and optional compensation capacitor, it provides reliable performance for power utilities, testing departments, and engineering units at local, municipal, and county levels. Its broad application range makes it an essential tool for installation, maintenance, and high-voltage testing in the power industry.
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معلمات المنتج
The work environment
Environment temperature:-100oC-50oC
Relative humidity:≤90%RH
The altitude:≤1000m
Main technical parameters and functions of the device
Rated Capacity: 324kVA
The input power:Three-phase 380V voltage, frequency: 50Hz
Rated Voltage: 54kV
Rated current: 6A
Working frequency:30-300Hz
Device output waveform: Sine wave
Waveform distortion rate: Output voltage waveform distortion rate ≤1%
Working time: Continuous 60min is allowed under rated load; Overvoltage 1.1 times 1 min
Temperature rise: Temperature rise ≤65K after continuous operation under rated load for 60min
The quality factor: Device Q≥30(f=45Hz)
Protection function: Over current, over voltage and flashover protection (see frequency conversion power supply for details)
Accuracy of measurement:Effective value of the system is 1.5
Exciter transformer
Rated Capacity: 9kVA
The input voltage: 0-400V,Single phase
The output voltage: 3kV
structure: dry type
Weight: About 50kg
Variable frequency power supply
Rated output capacity: 18kW
Working power supply: 380±10%V (three-phase), power frequency
The output voltage: 0-400v, single phase
Rated input current :45A
Rated output current: 45A
Voltage resolution:0.01kV
Accuracy of voltage measurement :1.5%
Frequency range: 30-300Hz
Frequency regulation resolution: ≤0.1Hz
Frequency stability: 0.1%
Running time: Continuous 60min at rated capacity
Noise level: ≤50dB
High voltage reactor
Rated Capacity: 54kVA
Rated Voltage:27kV
Rated Voltage: 2A
inductance: 68 H/single section
The quality factor: Q≥30(f=45Hz)
structure: dry type
Weight: About 75kg
Capacitor divider
Rated voltage: 60kV
High piezoelectric capacity:2500pF
Dielectric loss: tgσ≤0.5%
Voltage division ratio: 1000:1
measurement accuracy: Valid value of 1.5
Weight:About 10kg
Product Features & Advantages
1、Comprehensive Protection System
The device features configurable overvoltage, overcurrent, and zero-start protection, with adjustable threshold settings. Its intelligent flashover protection instantly responds to sample breakdowns, ensuring equipment safety.
2、Portable Field Operation
Designed with lightweight construction for enhanced mobility and convenient on-site deployment.
3、Flexible Testing Modes
Offers three operational modes (full-auto, manual, and auto-tuning/manual boost) to adapt to various field conditions and optimize testing efficiency.
4、Smart Data Management
Enables off-site data storage/printing with unique numbering for easy tracking and retrieval.
5、Intelligent Frequency Sweep
Allows customizable sweep range initialization and provides real-time LCD curve display for visual resonance point identification.
6、Upgradable DSP Platform
Incorporates modular DSP technology for customizable function expansion and user-friendly interface upgrades.
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AC resonant systems vs. alternatives
| Feature / Aspect | AC resonant test system (Rui Du type) | Conventional HV test transformer | VLF test set (for cables) |
| Power requirement for long, capacitive loads | Low input power, only covers system and load losses at resonance. | High input power, must supply full reactive current at 50/60 Hz. | Lower because of very low frequency but not suitable for all equipment types. |
| Equipment size and portability | More compact for same test voltage and load, easier to move and install. | Bulky and heavy at higher voltage/capacitance ratings, complex logistics. | Typically compact and portable for cable tests. |
| Typical applications | XLPE cables, GIS, power transformers, generators and other capacitive HV equipment. | General HV withstand tests, especially for smaller loads and lab environments. | Primarily MV/HV cable insulation assessment, not transformers or GIS. |
| Test frequency flexibility | Variable frequency around nominal power frequency to tune resonance and avoid network issues. | Fixed at 50/60 Hz, no frequency tuning capability. | Very low frequencies (e.g. 0.1 Hz) targeted to cable diagnostics. |
| Energy efficiency and stress on supply | High efficiency due to resonance; reduced stress on local power supply. | Lower efficiency for capacitive loads; higher demand on test supply. | Efficient for cables but not applicable to broad range of HV equipment. |
| Suitability for field testing | Well suited for on‑site tests of large equipment thanks to smaller supply rating and modular design. | Less suitable for very large field tests due to transportation and power constraints. | Very suitable for field cable tests but limited equipment coverage. |
Usage scenarios: before and after AC resonant systems
Scenario 1: 110 kV cable commissioning
With AC resonant test system: A suitably rated AC resonant test system enables full‑voltage on‑site tests of the assembled GIS, using variable frequency to optimize resonance and minimize input power, thereby shortening commissioning time while aligning with modern grid code and utility requirements.
FAQ about AC resonant test systems

































