Converter enhanced variable frequency power bus architecture

Abstract

An electric power generation and distribution system having a basic variable frequency distribution bus to which wide frequency variation tolerant utilization equipment is coupled and an enhanced frequency distribution bus to which wide frequency variation intolerant utilization equipment is coupled, comprises a variable speed generator driven by an external variable speed prime mover such as an aircraft engine. This generator produces output electric power having a frequency which varies with the speed at which the generator is driven. The system further comprises a converter which is electrically coupled to the generator and produces output electric power having a controlled frequency. A switching network operates to couple the generator to and decouple the converter from this enhanced bus when the frequency of the electric power produced by the generator is within a predetermined acceptable range to allow the generator to supply power thereto. The switching network also operates to decouple the generator from and couple the converter to the enhanced bus when the frequency of the electric power produced by the generator is outside this predetermined acceptable range. The converter then supplies the electric power requirements of the enhanced bus, ensuring that the utilization equipment coupled thereto is not exposed to electric power having a frequency outside an acceptable range. The converter may be operated to match the generator output waveform prior to transfer to allow a no break power transfer between the two sources.