Apparatus and method for controlling a multi-turbine installation

The invention is practiced by providing a plurality of turbine-driven systems each producing an output proportional to a respective control signal, means for generating a respective first output signal for each of the turbine-driven systems proportional to a respective first system-output indicating parameter, means for generating a respective error signal for each of the turbine-driven systems proportional to any deviation of a respective second system-output indicating parameter from a respective complementary portion of the combined second system-output parameters of the systems, and means for generating the respective control signal of each of said turbine-driven systems and proportional to any deviations of respective ones of the first output signal and the error signal from a respective predetermined reference value of said first parameter, whereby a predetermined relationship of the individual outputs of the turbine-driven systems is maintained. The invention further comprises a logic controlled switching means effective for determining the number of the turbine-driven systems within the plurality included for sharing combined outputs, electrically connecting each included turbine-driven system to the control apparatus, and electrically isolating each of those turbine-driven systems to be excluded therefrom.