Towards Precise Interpretation of Oil Transformers via Novel Combined Techniques Based on DGA and Partial Discharge Sensors

Area of Science:

• Electrical Engineering
• Power Systems Analysis
• Asset Management

Background:

• Power transformers are critical and costly components in electrical grids.
• Transformer failures lead to significant economic losses and operational disruptions.
• Effective diagnostic techniques are essential for ensuring continuous power supply.

Purpose of the Study:

• To integrate Dissolved Gas Analysis (DGA) techniques for improved power transformer fault diagnosis.
• To analyze Partial Discharge (PD) measurements in a case study transformer.
• To enhance the reliability and cost-effectiveness of power transformer condition monitoring.

Main Methods:

• Integration and classification of four recognized DGA techniques.
• Analysis of dissolved gas concentration in oil samples.
• Experimental setup and measurement of PD in a 66/11.86 kV-40 MVA power transformer.
• Validation using 532 samples from the Egyptian Electricity Transmission Company (EETC).

Main Results:

• Integration of DGA techniques significantly improves oil fault condition monitoring.
• The combined approach overcomes the limitations of individual diagnostic methods.
• PD measurements were successfully conducted and analyzed for the case study transformer.
• Precise interpretation of transformer condition is achievable through combined techniques.

Conclusions:

• Integrated DGA and PD testing provide a robust solution for power transformer diagnostics.
• This approach enhances operational reliability and reduces economic losses for utilities.
• The study validates the effectiveness of combined diagnostic techniques using real-world data.