GDTF Series 800kVA 400kV AC Resonant Test System for GIS
I. General information
GDTF-800/400 is specially designed for AC withstand voltage test for 220kV or below switch, GIS, instrument transformers and neutral point of main transformers. The system includes Variable frequency power supply, exciting transformer, reactor, and capacitive voltage divider.
Advantages in the power system application: 1. Small power of required power supply. The power source of series resonance uses the resonant reactor and test object capacitance to generate high voltage and high current. In the whole system, the power supply only needs to supply the part ofactive loss. Therefore, required test power is the 1 / Q of test capacity. 2. Light weight and small size. In the series resonant power supply, it does not use heavy high-power voltage regulators and traditional high-power power frequency test transformers. The resonant excitation power supply only needs 1/Q of the test capacity, which greatly reduces the weight and volume of the system, generally 1/10-1/30 of traditional test equipment. 3. Good waveform of output voltage. Resonant power source is resonant filter circuit, which improves the distortion of output voltage waveform and obtain good sine wave. It greatly prevents the test object from breakdown of harmonic peak. 4. High short-circuit current will not burn the fault point. In the status of series resonant, when the test object insulation weakness is breakdown, circuit detune immediately, and the loop current rapidly drop to 1 / Q of normal testing current. While tested by parallel resonant or testing transformer, the breakdown current rise dozens of times immediately. Therefore, testing by series resonant can find the insulation weakness effectively and high short-circuit current will not burn fault point. 5. Any recovery overvoltage is not appeared. When the test object breakdown, the resonance will be disappeared and high voltage also disappear immediately, arc extinguish at once, and the time of recovering voltage is long, it will disconnect power supply before reaching the flashover voltage. The voltage recovery process is a kind of energy accumulation of intermittent oscillation, the process is long, and any recovery overvoltage will not appear.
Compliance standard <Electrical equipment installation project electrical equipment handover testing standards>GB50150-2006 <High voltage resonance test device> DL/T849.6-2004 <Reactor> GB10229.88 <Electricity equipment preventive testing regulations>DL/T596-1996 <Coupling capacitors and capacitance voltage divider> IEC358 (1990) < High voltage test techniques> IEC60060
II. Features
1. With the protection function of over-voltage, over-current, zero-start, system detune (flashover). Over-voltage, over-current protection value can be set accordingly to user's need. Flashover protection starts when flashover and the flashover voltage value will be recorded for testing analysis. 2.The unit piece of the device is light, suitable for field use. 3.There are three kinds of working mode for user choosing according to on-site condition. Automatic mode, Manual mode, Automatic tuning manual boosting mode. 4. Data can be stored, and the storeddata No. are figures which is easy for identification and searching. 5. Frequency starting point can be set in the specified scope when the device sweep frequency automatically, sweep frequency direction can be selected upward or downward, meanwhile LCD displays the scanning curve, which is convenient to know if the resonant point found or not intuitively. 6. With DSP technology, which can increase or decrease functions and updated accordingly to the user's need, it also makes the human-machine interface more friendly.
III.TechnicalSpecifications
GDTF - means manufacturer's code. 800kVA means the maximum rated capacity of the equipment, the unit is kVA 400kV means the output voltage of the equipment, the unit is kV.
The rated voltage:
200kV-- meets AC withstand voltage testing of 110kV GIS and power cable. 400kV-meets AC withstand voltage testing of 220kV substation. 2. Output voltage waveform distortion rate: <1.0%. 3. Allowing continuous working time: one-time 30mins at rated value, continuous working 60mins for 35kV power cable. 4. Quality factor of the equipment: Q>50 5. Quality factor of making test for firepower generator: Q>10 (Related with load) 6. Quality factor of making test for power cable: Q>30 (Related with load) 7. Quality factor of making test for main transformers: Q>30 (Related with load) 8. Quality factor of GIS, circuit breakers in full load test: Q > 50 (Related with load) 6. Input power supply: Two phase 380V 7. Frequency adjusting range: 20-300Hz 8. System measurement accuracy: 1.5% 9. Over-voltage, over-current, zero-start protection
IV. Parameters for Individual Parts
1. Variable frequency power supplyGDTF -45kVA(1 set)
Rated output capacity: 45kVA
Working power supply: 380V±10%, 45-65Hz
Output voltage: 0-400V adjustable
Rated output current: 0-112.5A
Voltage resolution: 0.01kV
Voltage measuring accuracy: 1.5%
Frequency adjusting range: 30-300Hz
Frequency adjusting resolution: ≤0.1Hz
Frequency instability: ≤0.02%
2. HV Reactor GDDK-400kVA/200kV (2pcs)
Rated capacity: 400kVA
Rated voltage: 200kV
Rated current: 2A
Rated inductance: 264H (per set)
Continuous working time: 60mins
Temperature rise: <60K
Working frequency: 30-300Hz
3. Exciting Transformer GDJL-45kVA (1 set)
Rated capacity: 45kVA
Input voltage: 0-400V, single phase
Output voltage: 5/10/20kV
5kV can be used for 110kV power cable, 35kV substation test, 10kV can be used for 110kV power cable test, 20kV can be used for 220kV substation test.
Audited Supplier 
){kind=link}