CLNR Trial Analysis: RTTR for Secondary Transformers
Overview
Power system components are limited in their current carrying capacity by the conditions which surround them, in the case of Power transformers, the levels of ambient temperature, solar gain and wind speed (in particular for pole mounted transformers) all affect the ability to transfer power.
Higher ambient temperatures result in a reduced ability to transfer heat away from transformer components leading to reduced loading capability. Typically power system components such as transformers are rated based on a series of worst case conditions, to ensure secure power transfer capability under all possible scenarios. This however leads to high levels of redundant capacity, which, under the present rating systems are unable to be ‘unlocked’. This is primarily due to a lack of ‘real-time’ monitoring at the component sites as opposed to a lack of accurate modelling techniques.
Real Time Thermal Ratings (RTTR) aims to bridge this gap by using the real-time ambient conditions and necessary modelling parameters to provide increased visibility with regards to asset capability. Within the scope of the CLNR project, only ground-mounted transformers have been considered.
