How the WindSmart hydraulic drive train system works in a wind turbine: The wind turbine rotor is mounted on a shaft, which drives a fixed displacement hydraulic pump. A hydraulic circuit allows oil to flow from the pump to a variable displacement motor. That motor is directly connected to an asynchronous or synchronous generator. Thus, although the motor’s speed is (approximately) constant, the variation of the swash plate angle controls the oil flow that is returned to the hydraulic pump, and by doing so, it controls the speed of the fixed displacement pump and consequently the speed of the rotor.
