ABSTRACT
The gas turbine is a highly responsive, high speed piece of machinery. In an aircraft application, the gas turbine can accelerate from idle to maximum take-off power in less than 60 seconds. In industrial gas turbines, the acceleration rate is limited by the mass moment of inertia of the driven equipment. Controlling the gas turbine in each of these different configurations and applications requires the interaction of several complex functions. Some of the complexity can be simplified by considering the gas turbine as a gas generator and a power-extraction-turbine, where the gas generator consists of the compressor, combustor, and compressor-turbine. The control varies shaft horsepower of the gas generator turbine and power- extraction turbine by varying gas generator speed, which the control accomplishes by varying fuel flow. Controls can be divided into several groups: hydromechanical (pneumatic or hydraulic), electrical (hard wired relay logic), and computer (programmable logic controller or microprocessor).
