Single service

power transformers

Test of Power Transformers

Power Transformer Testing

HV / EHV TRANSFORMERS

On-site Diagnostic Testing of HV / EHV class of Transformers:

Our experience spans across power transformers of all voltage class upto 1200 kV and rating upto 500 MVA.

  • Voltage Ratio and Vector group confirmation test,
  • Frequency Response Analysis (FRA),
  • No-load excitation current measurement
  • Capacitance and dissipation factor measurement of the inner insulation
  • Capacitance and dissipation factor measurement of high-voltage bushings
  • Impedance measurements (short-circuit impedance, zero sequence impedance, FRSL method)
  • Analysis of winding damages with the FRA method
  • Moisture analysis of paper insulation by dielectric method (PDC+ FDS).
  • OLTC operation and dynamic contact resistance measurement
  • Winding Resistance Measurement
  • Thermography , Noise , Vibration Measurement
  • Routine Oil test, DGA, Furan
  • DP test of paper insulation.
  • On line & Off line Partial discharge measurements of  transformers

CURRENT TRANSFORMERS

On-site Testing of the HV/EHV class of Current Transformers

It is intended to perform automatic testing by CT Analyser on-site for utilities with very less testing time or by Primary injection test. The following tests can be performed:

 

  • Burden & CT winding resistance measurement
  • CT excitation characteristic according to IEC 60044-1, IEC 60044-6 (TPS, TPX, TPY) and IEEE C57.13. for knee-point voltages (up to 15 kV).
  • CT ratio & phase angle error measurement 
  • CT phase and polarity measurement
  • Determination of accuracy limiting factor, instrument security factor,
  • Test of CTs for knee-point voltages (up to 15 kV).
  • Capacitance and dissipation factor measurement of the inner insulation
  • Capacitance and dissipation factor measurement of high-voltage bushings
  • Moisture analysis of paper insulation dielectric method (PDC+ FDS) 
  • DGA test of oil.
  • On line & Off line Partial discharge measurements of CT.

CVT & PT

On-site Testing of the HV/EHV class of Potential Transformers and CVTs

  • Capacitance and dissipation factor measurement
  • Primary injection & Ratio test.
  • Moisture analysis of paper insulation by dielectric method (PDC+ FDS).
  • IR value with Polarization Index (PI) & Absorption Index (AI),
  • DC Resistance measurement
  • On line & Off line Partial discharge measurements.