All-electric (secondary power) airplane

Advances in electric/electronic technologies have allowed designers to develop very large-capacity power generator systems in anticipation of the requirements of next-generation aircraft. Engineers are confident that power electronics technology will meet the sometimes inordinate demands of those future aircraft because of the continuing development of very high-energy, highly efficient, light-weight, low-volume inverters and induction motors. The key to the operational success of any technological breakthrough in aircraft design is reliability, and such is the case with tomorrow's very large-capacity power generating systems. Although triple and quadruple redundancy can be designed into a fly-by-wire system powered by such a system, engineers are investigating the feasibility of using a system which is inherently very simple and highly reliable. Such a system could be a direct engine-driven ac generator system in which 270 Vdc, 28 Vdc, and other special power supplies are developed as required. In addition to its reliability and simplicity, the major advantage of the direct engine-driven generator is its efficiency. In addition, the military services have advocated adoption of a distributed power bus system designed to simplify power distribution to the loads and to restrict the power wires to the areas where the loads are located. This kind of configuration negates the problem of 'bus proliferation' which has become an outgrowth of the conventional radial power systems in current aircraft.