Variable Speed Constant Frequency (VSCF) Aircraft Electrical Power 771002
This paper describes the operation, design, performance, and application of high reliability, variable speed constant frequency (VSCF) aircraft electric power generating systems. A high frequency, multi-phase, brushless generator supplies power to a frequency converter which conditions the variable frequency generator output into precision 3-phase, 115/200V, 400 Hz aircraft power, using the cycloconverter principle. Systems have been built with ratings from 20 to 150 kva. For a 75 kva system, the weight to rating ratio is about 1.6 lbs/kva and rated load efficiency is 80%. Predicted MTBF for current systems is in the 2000 to 6000 hour range.