[2023] All Reasons for Transformer Overheating Explained

Reasons For Transformer Overheating

    Transformers are the most important machine used in electric power system to step-up and step-down the voltage and current level. Overheating is one of the major problem that occurs in transformers. Overheating of the transformer increase power losses in the transformer, damage to the insulation and reduces the lifespan of the transformer.

    Transformer may get over-heated due to various reasons. Some of the major reasons responsible for the overheating of a transformer are listed below.

1) Overload on transformer

    Excessive loading on a transformer means flow of current more than the capacity of a the transformer results overheating in a transformer.

2) Low Transformer Oil Level

    When transformer oil level in transformer is low, it reduces the cooling capacity of the transformer resulting overheating of the transformer. Insulating oil level in transformer must be checked regularly either by visual inspection or using oil monitor device like mog (magnetic oil guage) and must be maintained to prevent the low transformer oil level.

2) Moisture in transformer oil

    Moisture in transformer oil reduces reduces its insulating properties resulting in breakdown of transformer oil. Due to the presence of moisture, bubbles are formed in transformer which disrupt the flow of transformer oil and reduce cooling capacity of the transformer oil resulting increase in overheating of the transformer.

3) Failure of cooling system

    Malfunctioning of the cooling equipment such as blockages in the transformer oil circulation, dust in air vent and failure of the cooling fans results overheating in a transformer.

4) Insulation failure

    Damaged or wore insulation of a transformer lead to arcing and heat up results overheating of the transformer.

5) Current in Neutral 

    Current appeared in the neutral of the transformer due to unbalanced load between the phase resulting overheating of the transformer.

6) Sustained Over-voltage

    Excessive heating for long period of time can overexcite the transformer resulting overheating of the transformer.

7)Unbalanced Load to the transformer

    High difference in load between the phases of a transformer results in overheating of the transformer.

8) Fluctuated loads

    Excessive fluctuation of load on a transformer results overheating of the transformer.

9) Leakage current

    Leakage current through weakened part of the insulation results in overheating of the transformer.

Conclusion

    Hope, you have clearly understand about all the reasons responsible for overheating in transformer in electrical power system. Make sure to leave your opinion and suggestion about this in the comment section below.

References

• electrotechnik.net