Understanding DGA of Transformer oil (Topic: Hydrogen)
Hydrogen typically forms as a byproduct of the thermal or electrical degradation of the oil and the transformer insulation system.
Significance of Hydrogen in Transformer Oil:-
1. Degradation Indicator: The presence of hydrogen in transformer oil indicates that the oil or the insulation system is undergoing thermal or electrical degradation. This can be due to overheating or electrical discharges within the transformer.
2. Oil Quality: Elevated levels of hydrogen can suggest that the oil is deteriorating, which may compromise its insulating properties and overall performance.
3. Transformer Health: High levels of hydrogen can be a sign of potential problems within the transformer, such as excessive heating or partial discharge, which could affect the transformer’s reliability and longevity.
Interpretation According to IEC and IEEE Standards
IEC 60567
IEC 60567 provides guidelines for the measurement of dissolved gases, including hydrogen, in transformer oil. The standard outlines the methods for detecting and quantifying hydrogen levels.
– Normal Levels: For typical operation, hydrogen levels in transformer oil should be low, ideally less than 1 mg/kg (ppm). Low levels suggest that the transformer is operating normally without significant degradation.
– Elevated Levels: Hydrogen levels between 1 and 5 mg/kg (ppm) can indicate early signs of degradation or partial discharge. These levels warrant closer monitoring and further investigation.
– High Levels: Levels exceeding 5 mg/kg (ppm) are considered high and suggest significant thermal or electrical issues within the transformer. Immediate action is required, including detailed inspection and possibly corrective measures.
IEEE C57.104
IEEE C57.104 provides general guidelines for interpreting dissolved gases in transformer oil, including hydrogen. It emphasizes the need to evaluate hydrogen levels in conjunction with other diagnostic data.
– Normal Range: Generally, hydrogen levels below 1 mg/kg (ppm) are considered normal.
– Elevated Levels: Levels between 1 and 5 mg/kg (ppm) suggest potential degradation or partial discharge and should prompt further investigation.
– High Levels: Levels above 5 mg/kg (ppm) indicate significant issues, such as severe overheating or electrical faults, requiring immediate inspection and corrective actions.