Dynaload will characterise the long-term mechanical endurance of transformer insulation under heavy dynamic loading conditions through testing and modelling.
Benefits
Dynaload will benefit a number of areas associated with the energy system transition.
A reliable electric power infrastructure is vital for the energy system transition - and technology-driven endeavour to reduce greenhouse gas emissions through electrification and increased ratio of renewables in the energy mix. Ultimately, a better understanding of risks from rapid dynamic loading of power transformers will strengthen the existing and future energy infrastructure: To ensure access to affordable, reliable, sustainable and modern energy for all. Resilient and dependable power transformers are prerequisites for high-powered charging facilities for heavy duty electrically powered zero-emission transportation. It will bring better maintenance procedures, less risk of failures and improved security of supply.
There are also clear environmental and sustainability benefits. Reliable physical models for winding insulation under dynamic loading, supported by real-life sensor data from an in-service transformer, will facilitate the development of hybrid modelling / digital twins for condition-based maintenance, and allow more precise estimates of transformer life expectancy.
Learnings
Outcomes
Key outcomes are summarised below. Where quantitative benefit estimates are not available (research based project), outcomes are stated in terms of new learning, capability demonstrated and readiness advanced.
- Online monitoring feasibility demonstrated: multi-year in-service clamping pressure and temperature monitoring delivered a unique dataset for understanding clamping behaviour under real operating conditions.
- New learning on pressboard behaviour: moisture and surface preparation/sizing were identified as the most significant factors influencing plastic deformation and clamping pressure evolution; oil impregnation had limited direct effect on clamping pressure behaviour in the tested conditions.
- Validated predictive capability: a thermo-mechanical model was developed and validated against field measurements, supporting future use in digital-twin / condition-based maintenance workflows.
- Operational insights: clamping pressure was shown to vary with winding temperature, ambient conditions and energisation effects, highlighting the importance of accounting for cooling and no-load losses during operational events.
- Standards/guidance contribution: project findings were shared with international working groups (including CIGRE) to inform future guidance on winding insulation materials under dynamic loading.
The project was registered to progress from TRL3 (Proof of Concept) to TRL5 (Pilot Scale). The in-service monitoring demonstration and validated modelling are consistent with achieving pilot-scale validation, with further replication across additional transformer types recommended for wider roll-out.
Lessons Learnt
- Moisture control and measurement are critical; moisture absorption/drying cycles materially affect swelling/shrinkage and therefore clamping pressure retention.
- Sample preparation (sizing, surface preparation/milling, drying under pressure) significantly influences results and must be standardised to enable meaningful comparisons.
- In-service sensor data is essential to validate models and reveal combined effects of loading, energisation, ambient temperature and cooling system dynamics.
- Monitoring projects should plan for calibration, timestamp alignment, data gaps and long-term sensor reliability from the outset.
- Model development benefits from early access to representative operational data and clear definition of boundary conditions (e.g., tie-plate/core temperature estimation).
