Continuous determination of assets’ dynamic loadability by using thermal inertia and real-time conditions

Electricity grid operators worldwide face challenges in meeting the demand for transport and distribution capacity. Traditional methods use static assumptions for determining nominal loadability, but modern sensing, modelling, and control capabilities offer opportunities for optimization. A framework is proposed for dynamic grid loadability, maximizing loadability by forecasting asset temperatures. For power transformers and underground cables, asset specifications are combined with short-term load and ambient temperature forecasts to determine dynamic loadability. A field test demonstrated this concept realizing transformer loading up to 169% (ONAN mode) or 123% (ONAF mode), and cable loading of 113% of nominal loadability, while temperatures remained far within safe limits. The thermal models showed low MAE of 2.3 and 0.9 °C for transformers and cables respectively. With the right approach and precautions, dynamic loading can increase loadability of the existing grid up to 50%, which can be used to accelerate the energy transition.