METHOD AND APPARATUS FOR EXTRACTING ENERGY FROM A FLUCTUATING ENERGY FLOW FROM A RENEWABLE ENERGY SOURCE

摘要

An energy extraction device and method for extracting energy from a fluctuating energy flow from a renewable energy source. A hydraulic pump is driven by a rotating shaft, driven in turn by a renewable energy source. A hydraulic motor drives a load and a high pressure manifold communicates between the pump, motor and an elastically deformable fluid retaining body. The hydraulic pump and hydraulic motor comprise working chambers displacing a volume of working fluid selectable on each cycle of working chamber volume by the control of electronic valves. The pressure in the high pressure manifold is measured and the net rate of displacement of working fluid by the hydraulic pump is selected responsive thereto to regulate the torgue applied to the said rotating shaft. The net rate of displacement of working fluid by the hydraulic motor is selected to smooth the energy flow to the load. The net rate of displacement of working fluid by the hydraulic motor is selected to cause the pressure within the high pressure manifold to tend towards an optimum. The optimum is variable and can be selected to optimise the efficiency of power transmission from the rotating shaft to the load or to increase the longevity of the energy extraction device.