Power transformers are an essential part of our power grid.
A transformer failure is a costly incident that require time consuming and expensive replacement work and may result in fires and explosions causing significant collateral damage, in addition to threatening the security of supply of electricity.
The grid is currently exposed to new dynamic loads from renewable energy sources, high-powered charging for electric transportation, and frequent start/stops of hydropower due to the market demand.
The resulting grid operation patterns will accelerate thermal ageing and mechanical degradation of the transformer insulation materials and changes the clamping forces that ensure the transformers structural integrity.
This reduces the transformerʼs lifetime. Their insulation degrades faster, and the clamping forces inside them shift. Left unchecked, this could mean more frequent power outages and a threat to the security of our electricity supply.
While thermal ageing of winding insulation is widely studied, the evolution of clamping forces over time during operation is not well understood.
It is uncertain how resilient transformers are to short-circuit faults, what the margins of safe operation are, and how this is affected by increasingly dynamic loads. Improved knowledge on the clamping system of a transformer is vital to increase electrification while maintaining security of supply of electricity.
ClampIT will find the main factors which determine development of clamping force loss through laboratory studies of long-term ageing and degradation of insulation materials, and measurement and modelling of clamping forces in transformers under both normal operation and dynamic loads.
This will lay the foundation for improved transformer designs, better utilisation of available capacity, safe operation and condition-based maintenance.
Project goals:
ClampIT will find the main factors which determine loss of clamping force during long-term and dynamic loading.
Laboratory studies of insulation ageing, combined with online measurement and modelling of clamping forces, will point the way to better and safer transformer designs.
The project will:
- Examine how mechanical stress, temperature, moisture and aging affect the mechanical properties of transformer insulation materials under both rapid and transient long-term dynamic stress.
- Monitor transformer clamping forces, identify degradation patterns and evaluate which operational events accelerate that degradation. Use sensor data and condition assessment methods to improve asset management.
- Develop and validate a numerical model that predicts the long-term evolution of clamping forces in transformers under relevant service conditions.
- Disseminate and exploit project results among industry, academia, and the wider public to contribute to future standards and further innovation.