An MVA power transformer is a high-capacity transformer rated in megavolt-amperes, typically used in transmission and sub-transmission grids. Ratings from 10 to 1,000 MVA are common for generation step-up units, autotransformers, and large substation transformers. The MVA metric captures thermal load capability and reflects both voltage and current handling. Such transformers are designed for high insulation strength, robust cooling systems (ONAN/ONAF/ODAF), on-load tap changers, and strict short-circuit withstand requirements.