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 characteristics 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.

FAQs

1. Why is it important to test power transformers?

Testing power transformers is important because it helps ensure that the components of transformers are working properly and reduces the risk of failure.

2. What are some common tests performed on power?

Common tests for power transformers include turn ratio resting, insulation resistance testing, power factor testing, and resistance testing.

3. How often should power transformers be tested?

Testing transformer oils and insulating oils regularly is standard industry practice. Utility companies typically perform routine electrical testing on a 3-5 year rotation.

4. Who can perform power transformer testing?

Power transformer testing demands expertise and specialized equipment. It must be performed by a professional electrical engineer or technician with the appropriate expertise and experience.

5. What are the benefits of testing power transformers?

The testing of power transformers has the following advantages:

Regular testing can help ensure the safety of transformers and reduce the risk of fires or explosions.
It saves unexpected repair costs by detecting potential threats earliest.
And helps enhance the performance of the transformer.