Lightweight high-efficiency energy-storage transformers

A study undertaken to determine the potential improvement in efficiency of energy-storage transfers is described. Energy stores of 5 MJ and 1 MA were sized and studied. The performance of transformers made from conductor-grade aluminium was compared with that of transformers made from hyperconductor. It was found that the hyperconductor results in considerable improvement in performance. It is believed that hyperconducting aluminium can be used to build energy storage inductors and transformers that store at least 15 kJ/kg. This specific energy is a great improvement over present technology. More importantly, the increased specific energy comes with improved efficiency, further reducing power system mass. The limit of 15 kJ/kg is due to strain limit in the high-purity aluminium filaments. The specific energy can be increased to 50 to 100 kJ/kg by using a stiff external structure. The structure will not be simple, but it is suggested that the benefit of decreased power system mass and volume is worth the initial technical complexity