Test of Power Transformers

High Voltage 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.