Impulse Voltage Test Laboratory consists of an indoor laboratory and an outdoor laboratory test bay. Indoor laboratory is a high voltage test hall of dimensions 50 m x 40 m x 35 m housing a 3MV, 150kJ impulse voltage generator which has 15 stages and is generally used for carrying out lighting impulse voltage and switching impulse voltage tests on high voltage equipment of rating upto 500 kV. The generator is also suitably configured with series and parallel combinations of capacitors, resistors and an additional inductor to generate the impulse currents necessary to be passed through the surge arrester for measuring the residual voltage. Apart from this, the division has a rain making equipment and indoor power frequency testing transformers of ratings a) 100kV, 50mA and b) 600kV, 2000kVA.
The outdoor test bay consists of a 1800kV, 2000kVA cascade transformer comprising of three 600kV, 2000kVA transformer units. The AC test voltage up to 1000 kV from the outdoor bay can be taken into the high voltage test hall by means of a wall bushing. This setup is used for conducting power frequency voltage tests (Dry & Wet) and RIV & corona tests up to and including 500kV.
Suitable infrastructure is available to mount all types of insulator strings upto 500 kV class for testing including material handling facility consisting of a 24 Ton (boom end max), 1 Ton (with boom in telescopic mode) mobile crane and 5 & 3 Ton fork lifts. This setup is used for conducting power frequency voltage tests (Dry & Wet) and RIV & corona tests up to and including 500kV.
With the equipment installed at present, it is possible to undertake tests on all major electrical equipment like power transformers, current transformers, potential transformers, air break switches, isolators, cables, bushings, insulators power line accessories etc. up to and including 550 kV system.
Shri. Prabhakar C
Joint Director and Head of the Division
Central Power Research Institute, Bengaluru
Email: prabhakar@cpri.in
Phone: 080-2207 2377
Mobile: 9845152154
Major Product/Equipment tested with applicable standards:
- High voltage Insulator Strings as per IEC 60383, IEC 61109, IEC 60437
- Solid Core Post Insulators as per IEC 60168, Composite station post insulators as per IEC 62231-1
- Transformers and reactors as per IS 2026 and IEC 60076
- Instrument Transformers as per IEC 61869, IS 16227
- High voltage switchgear and control gear as per IEC 62271-1, IEC 62271-100, IEC 62271-102, IEC 62271-200 and IEC 62271-203
Major tests Carried Out:
Lightning impulse voltage test, Switching impulse voltage test, Power-frequency voltage test, Radio interference voltage test, Corona test on high-voltage equipment up to 500 kV rating
Range of the test ratings possible:
This Laboratory can undertake the following tests as per National & International Standards:
- Lightning impulse voltage tests upto 2,400 kV (Peak) level.
- Switching Impulse Voltage Dry & Wet Tests up to 1.5 MV peak level.
- Steep front impulse voltage test on polymer insulators of length upto 500 mm and porcelain insulators up to and including 33 kV insulators.
- Corona Inception and Extinction Voltage Test and RIV measurements upto & including 500 kV system
- Power frequency voltage Dry & Wet withstand tests upto 1,000 kV (rms) level
- Porosity test on porcelain insulator fragments.
- Mechanical performance/Electro-Mechanical test upto 40 tonnes on porcelain insulators.
- Mechanical performance/mechanical test upto 40 tonnes on polymeric insulators.
- Thermal mechanical load cycle tests.
- Under oil puncture test for porcelain insulators up to and inclusive of 33kV rating.
- Temperature cycle test on insulators up to & including 220kV rating.
- Ferro Resonance tests on CVT at rated voltage upto 220 kV.
- Surge withstand test.
- Voltage distribution tests on insulator strings
- DC withstand & flashover tests under dry condition upto 280 kV.
- Performance check on high voltage dividers as per IEC 60060-2.
- Performance check of digitizers used for impulse measurements as per IEC 61083-1.