Parallel operation of aircraft A-C generators

THE ELECTRIC POWER requirements for aircraft have shown an increased demand for a-c power. Repeatedly, weight studies made by airframe manufacturers have shown a saving through the generation and distribution of a-c power directly rather than the generation of d-c power and the ultimate conversion to meet the a-c power requirements. In addition, the over-all efficiency of the a-c system is higher than that of a d-c system with conversion to a-c power. For the most part, the a-c power requirements have been met through the use of single-generator systems or combinations of single-generator systems using split bus arrangements. However, the need for higher reliability systems having greater reserve capacity and making better utilization of generator capacity through the diversification of load equipment leads to the conclusion that parallel systems should be used in future aircraft. Reliable parallel operation of a-c machines requires the proper integration of many components.