What Are The Effects of Operating A Transformer at Too High A Temperature?

Transformer operating temperature is too high will bring the following aspects of the adverse effects:

First, the impact of transformer insulation materials

Accelerated aging

Insulating materials at high temperatures will occur thermal aging, reducing its insulating properties. As the temperature rises, the molecular structure of the insulating material will gradually change, resulting in the material becomes hard, brittle, lose elasticity and flexibility.

Long-term high-temperature operation will make the life of the insulating material greatly shortened, increasing the risk of transformer failure.

Reduce insulation strength

High temperature will make the resistivity of the insulating material decreases, thus reducing its insulation strength. When the insulation strength is reduced to a certain extent, the transformer may occur inside the partial discharge, flashover and other phenomena, and in severe cases, it may even cause short circuit failure.

Second, the impact of transformer oil

Oil deterioration

Transformer oil at high temperatures will occur oxidation, cracking and other chemical reactions, resulting in oil degradation. Deterioration of the transformer oil colour darkens, viscosity increases, acid value rises, insulation performance decreases.

Oil deterioration will also produce sediment and sludge, blocking the transformer's heat dissipation channel, affecting the transformer's heat dissipation effect.

Gas production increase

High temperature will make the transformer oil decomposition to produce a variety of gases, such as hydrogen, methane, ethane and so on. The production of these gases will increase the pressure inside the transformer, which may lead to transformer explosion in serious cases.

Third, the impact on other parts of the transformer

Winding deformation

High temperature will make the transformer winding resistance increase, resulting in increased heating of the winding. Long-term high temperature operation will make the winding insulation material aging, shrinkage, thus causing winding deformation.

Winding deformation will affect the electrical performance of the transformer, increase the loss of the transformer, and may even lead to transformer short circuit failure.

Iron core overheating

High temperature will make the magnetic permeability of the transformer core decrease, thus increasing the loss of the iron core. The increase in iron core losses will lead to an increase in iron core temperature, further exacerbating the heat of the transformer.

Iron core overheating will also make the core of the insulation material aging, reduce the insulation performance of the core.

Fourth, the impact on the overall performance of the transformer

Reduce efficiency

High temperature will make the transformer loss increase, thus reducing the efficiency of the transformer. Transformer losses mainly include copper losses and iron losses, high temperature will make the winding resistance increases, the core permeability decreases, thus increasing copper losses and iron losses.

Impact on reliability

Transformer operating temperature is too high will increase the probability of its failure, reducing the reliability of the transformer. High temperature will make the transformer's insulating material aging and deterioration, winding deformation, iron core overheating and so on, all these problems may lead to transformer failure.

Here are some ways to reduce the operating temperature of the transformer:

First, improve the heat dissipation conditions

Optimise ventilation design

Ensure that the transformer is installed in a well-ventilated location with no obstacles around it to block air flow. Consideration can be given to increasing vents, installing fans or ventilation ducts, etc., in order to improve air flow and enhance heat dissipation.

For transformers installed indoors, a forced ventilation system, such as installing exhaust fans or air conditioning equipment, can be used to keep the indoor temperature within a suitable range.

Adoption of high-efficiency radiator

Choose radiators with good heat dissipation performance, such as chip radiators and corrugated radiators. These radiators have a large heat dissipation area and good heat transfer performance, which can effectively reduce the temperature of the transformer.

Regularly check the cleanliness of the radiator and remove the dust and dirt on the surface of the radiator to ensure the heat dissipation effect.

Second, reduce the load

Reasonable distribution of load

According to the capacity and load characteristics of the transformer, reasonably distribute the load to avoid long-term overload operation of the transformer. The load rate of the transformer can be reduced by adjusting the access sequence of the load and optimising the running time of the load.

For seasonal loads or temporary loads, standby transformers or peak shifting transformers can be considered to reduce the burden on the main transformer.

Improve power factor

Improving the power factor of the load reduces the reactive power loss of the transformer and thus reduces the temperature of the transformer. The power factor can be improved by installing reactive power compensation devices such as capacitors and reactors.

Third, strengthen the maintenance management

Regular inspection and maintenance

Regular inspection and maintenance of the transformer, including checking the insulation performance of the transformer, oil quality, winding temperature and so on. Timely detection and treatment of transformer faults and hidden dangers to ensure the normal operation of the transformer.

Regularly clean the transformer, remove dust and dirt on the surface of the transformer, and maintain good heat dissipation of the transformer.

Control ambient temperature

Try to install the transformer in a lower temperature environment, avoid direct sunlight and high temperature environment. You can consider setting up sun-shading facilities or heat-insulating materials around the transformer to reduce the impact of ambient temperature on the transformer.

Fourth, the use of advanced technology

Application of new insulation materials

Adoption of new insulation materials, such as high-temperature-resistant insulation materials, nano insulation materials, etc., can improve the insulation and heat-resistant properties of the transformer and reduce the operating temperature of the transformer.

Adoption of intelligent cooling system

The application of intelligent cooling system, such as temperature sensors, controllers, cooling fans, etc., can be automatically adjusted according to the temperature of the transformer cooling system operation status, to achieve precise cooling, improve cooling efficiency, reduce the operating temperature of the transformer.