Abstract: A power generating system includes a main engine operated over a range of speeds, an electric generator, and a hydrostatic transmission drivably connecting the engine with the generator to drive the generator at a desired speed. The hydrostatic transmission includes one or more variable pumps. A controller monitors the pump pressure and the generator frequency. The pressure set point is used with the monitored pressure to control the pump output. The pressure set point varies with the generator load, and is adjusted based on the deviation of the generator frequency from a predetermined desired electric power frequency. When multiple pumps are used to drive the motor, the pumps are operated sequentially such that all except one pump is either off or at maximum output.

Abstract: A power generating system includes a main engine operated over a range of speeds, an electric generator, and a hydrostatic transmission drivably connecting the engine with the generator to drive the generator at a desired speed. The hydrostatic transmission includes one or more variable pumps. A controller monitors the pump pressure and the generator frequency. The pressure set point is used with the monitored pressure to control the pump output. The pressure set point varies with the generator load, and is adjusted based on the deviation of the generator frequency from a predetermined desired electric power frequency. When multiple pumps are used to drive the motor, the pumps are operated sequentially such that all except one pump is either off or at maximum output.