110KV series resonant withstand voltage device

110KV series resonant withstand voltage deviceProduct Overview
This device is mainly designed and manufactured for AC withstand voltage testing of 10kV, 35kV cables, generators, 110kV and below power main transformers, bus switches and all other electrical main equipment. The reactor adopts multiple separate designs, which can meet the requirements of high voltage and low current equipment testing conditions, as well as the requirements of low voltage AC withstand voltage testing such as 10kV cables. It has a wide range of applications and is an ideal withstand voltage equipment for high voltage testing departments and power installation and maintenance engineering units at the prefecture, city, and county levels.
The device mainly consists of a variable frequency power supply, an excitation transformer, a reactor, and a capacitive voltage divider.
110KV series resonant withstand voltage deviceAdvantages:
1. The required power capacity is greatly reduced. Series resonant power supply generates high voltage and high current through resonance between resonant reactor and the tested capacitor. In the entire system, the power supply only needs to provide the active consumption part of the system. Therefore, the required power supply for the experiment is only 1/Q of the test capacity.
2. The weight and volume of the equipment have been greatly reduced. In a series resonant power supply, not only is the bulky high-power voltage regulating device and ordinary high-power power frequency test transformer eliminated, but the resonant excitation power supply only requires 1/Q of the test capacity, greatly reducing the system weight and volume, usually 1/10-1/30 of ordinary test devices.
3. Improve the waveform of the output voltage. A resonant power supply is a resonant filtering circuit that can improve the waveform distortion of the output voltage, obtain a good sine waveform, and effectively prevent the accidental breakdown of the test sample by harmonic peaks.
4. Prevent large short-circuit currents from burning the fault point. In the series resonance state, when the weak point of the insulation of the test sample is broken down, the circuit immediately disengages and the loop current rapidly drops to 1/Q of the normal test current. However, when conducting voltage withstand tests in parallel resonance or test transformer mode, the breakdown current immediately increases by several tens of times. Compared with the two, the short-circuit current is hundreds of times different from the breakdown current. So, series resonance can effectively identify insulation weaknesses without the concern of large short-circuit currents burning the fault point.
5. There will be no overvoltage recovery. When the test sample breaks down, due to the loss of resonance conditions, the high voltage immediately disappears, the arc immediately extinguishes, and the process of re establishing the recovery voltage is long. It is easy to disconnect the power supply before reaching the flashover voltage again. This voltage recovery process is an intermittent oscillation process of energy accumulation, which is long and does not result in any recovery overvoltage.
Technical features:
1. The device has protection functions such as overvoltage, overcurrent, zero start, and system detuning (flashover). The overvoltage and overcurrent protection values can be set according to user needs. When the test sample flashes, the flashover protection action can be taken and the flashover voltage value can be recorded for experimental analysis.
2. The entire device is lightweight, with a maximum weight of no more than 40kg, making it easy to use on site.
3. The device has three working modes, which facilitate users to flexibly choose according to the on-site situation and improve the testing speed.
The working modes are: fully automatic mode, manual mode, automatic tuning, and manual boost mode
4. It can store data with numerical numbers, making it convenient for users to identify and search.
5. When the device automatically scans the frequency, the starting point of the frequency can be set arbitrarily within the specified range, and the scanning direction can be selected upwards or downwards. At the same time, the LCD screen displays the scanning curve, making it convenient for users to intuitively understand whether the resonance point has been found.
6. Adopting DSP platform technology, it is convenient to add or remove functions and upgrade according to user needs, making the human-machine exchange interface more user-friendly.
Technical Specifications
technical indicators
1. Rated voltage:
45kV - meets the AC withstand voltage test of 10kV cable;
135kV - meets the AC withstand voltage test of 35kV cables and 35kV systems;
270kV - meets the AC withstand voltage test of 110kV system;
2. Distortion rate of output voltage waveform:<1.0%
3. Allowable continuous working time: Under rated conditions, it can work for 30 minutes at a time. When the 35kV cable is withstand voltage, it can work continuously for 60 minutes
4. Quality factor of the device itself: Q>50
5. Quality factor at full load during thermal power generator testing: Q>10 (load dependent)
6. Quality factor under full load during cable testing: Q>30 (load dependent)
7. Quality factor of main transformer test at full load: Q>30 (load dependent)
8. GIS， Quality factor of switch and other tests at full load: Q>50 (load dependent)
9. Input power supply: single-phase 380V
10. Frequency adjustment range: 20Hz~300Hz
11. System measurement accuracy: 1.5%
12. The device has protection functions such as overvoltage, overcurrent, and zero start
One variable frequency power supply
Rated power: 15kVA;
Input voltage: single-phase 220V or 380V ± 10% 45-65Hz
Output voltage: adjustable from 0 to 400V
Output voltage frequency: 30-300Hz
0.1Hz step adjustable
Frequency instability ≤ 0.02%
Output current: 0~37.5A
High voltage reactor（共6台）： 45kV/1A
Rated working voltage: 45kV
Rated working current: 1A
Rated inductance: 100H
Continuous working time: 60 minutes
Temperature rise: less than 60 degrees
Working frequency: 30-300Hz
Motivate 1 unit
Rated capacity: 15kVA
Input voltage: 200V/400V
Output voltage: 1.5/3/5/15kV, 1.5kV is used for 10kV cable and 10kV substation withstand voltage test; 3kV is used for 35kV cable withstand voltage test; 15kV is used for voltage withstand test of 110kV substation system
One capacitive voltage divider270kV pure capacitive type:
Self capacitance: 500pF
Working frequency: 30-300Hz
Rated voltage: 135kV/1000pF, 270kV/500pF