Control of Regenerative Gas Turbine Auxiliary Power Units

An analytical derivation is presented of a recuperated engine with two types of speed control. The primary control manipulates fuel to control speed. An auxiliary control used only during large alternator load removals manipulates compressor bleed flow to control speed.

A breadboard control system was designed to accomplish the two types of speed control, and its operation was demonstrated on the AiResearch Model GTPR807 recuperated engine. The results show that satisfactory control design techniques are available for the precise speed regulation of recuperated gas-turbine-driven alternator sets.