Abstract: A pumped heat storage apparatus has a prime mover, a power take off, first and second fluid working machines functioning as a compressor (8) and as an expander (10), a working fluid circulation pathway with high and low pressure sides, and high and low temperature heat exchangers (18A-B). The heat exchangers operate using direct contact between gaseous working fluid and solid thermal storage media, such as glass beads, which move in opposite directions, typically using an augur (44). The system is reversible between energy storage and energy recovery modes and when it reverses, the direction of movement of the working fluid and the thermal storage media reverses. The apparatus may very rapidly swap between energy storage and energy recovery while having a high capacity and energy throughout.

Abstract: A valve unit for a fluid working machine comprise a valve having a valve member (and optionally a valve seat), a valve actuator coupled to the valve member, and an electronic actuator controller which is integral to the valve unit and configured to actively control the valve actuator to thereby control the valve member.

Abstract: A valve unit for a fluid working machine comprise a valve having a valve member (and optionally a valve seat), a valve actuator coupled to the valve member, and an electronic actuator controller which is integral to the valve unit and configured to actively control the valve actuator to thereby control the valve member.

Abstract: The present invention provides a cooling system such as employed in cooling a heat source and a transmission system having said cooling system integrated therewith. The cooling system further includes a pump for supplying hydraulic fluid under pressure to a motor for driving a fan employed in the cooling process. In operation, a controller initiates operation of the pump such as to supply hydraulic fluid to said motor only when needed, thereby to improve the efficiency and controllability of the cooling system.

Abstract: It is intended to provide a power generating apparatus of renewable energy type which obtains desired torque rapidly in response to changes of the renewable energy as well as a method of operation such an apparatus.

Abstract: In view of the problems above, it is an object of the present invention is to provide a power generating apparatus of renewable energy type which can achieve a desired output of the hydraulic motor and a stable power generation regardless of changes of the renewable energy as well as a method of operation such an apparatus.

Abstract: The invention provides a method of operating an energy extraction device such as a wind turbine comprising a hydraulic pump driven by and applying torque to a rotating shaft, a hydraulic motor driving a load, a high pressure manifold in fluid communication with an outlet of the hydraulic pump and an inlet of the hydraulic motor and being selectively placed in fluid communication with a fluid accumulator, at least one low pressure manifold in fluid communication with an outlet of the hydraulic motor and an inlet of the hydraulic pump, at least one of the hydraulic pump or hydraulic motor is a digital hydraulic machine, characterised by interrupting fluid communication between the fluid accumulator and the high pressure manifold responsive to detection of a fault event.

Abstract: An object of the present invention is to provide a wind turbine generator system and an operation control method thereof, which has a superior operation efficiency and stability at a low wind speed and during the occurrence of a gust and is equipped with Ride Through function at Grid low voltage condition. The wind turbine generator comprises a hydraulic pump of a variable displacement type which is rotated by the main shaft, a hydraulic motor of a variable displacement type which is connected to the generator, and a high pressure oil line and a low pressure oil line which are arranged between the hydraulic pump and the hydraulic motor. An accumulator is connected to the high pressure oil line via an accumulator valve. ACC valve control unit controls opening and closing of the accumulator valve based on at least one of wind speed and the state of the grid.

Abstract: An annular valve (1) has an annular valve member (4) and inner and outer annular valve seats (12, 14). Inner and outer sealing ridges (8, 10) are formed either on the annular valve member or on the valve seats. The inner sealing ridges are more resistant to plastic deformation than the outer sealing ridges. They may be thicker, or made from a harder material. Thus, the annular valve better resists damage arising from greater plastic deformation of the inner sealing ridge than the outer sealing ridge due to greater forces (Fi, Fo) acting on the inner sealing ridge than the outer sealing ridge in use.

Abstract: A power generating apparatus includes a rotating shaft, a hydraulic pump driven by the rotating shaft, a hydraulic motor driven by pressurized oil supplied from the hydraulic pump, and a generator coupled to the hydraulic motor. Each of the hydraulic pump and motor includes working chambers each defined by a cylinder and a piston, a high pressure manifold and a low pressure manifold. Each of the high and low pressure manifolds includes branch channels connected to the working chambers and a merging channel connected to a high or low pressure oil line. The branch channels are equipped with high or low pressures valves, joined together and merged into the merging channel.

Abstract: A renewable energy turbine generator (1), such as a wind turbine generator, comprises a hydraulic pump (20), a hydraulic motor (24) and an oil circuit (26, 28) connecting the hydraulic pump and the hydraulic motor. Oil in the low pressure side (28) of the oil circuit is cooled and supplied to the working chambers (95) of the hydraulic pump. A reduced temperature oil feed provides additionally cooled oil to the bearings of the hydraulic pump and the hydraulic motor. Thus, cooler and more viscous oil is supplied to the bearings (84) of the hydraulic pump and/or hydraulic motor and warmer and less viscous oil is supplied to the working chambers, increasing the efficiency and lifetime of the bearings and of the working portions of the hydraulic pump and motor.

Abstract: An object of the present invention is to provide a wind turbine generator and a tidal current generator equipped with a hydraulic transmission with a combination of a hydraulic pump and a hydraulic motor and which has a superior productivity and maintainability. The wind turbine generator 1 has the hydraulic transmission 10 for transmitting the rotation energy of a main shaft 8 to a generator 20. The hydraulic transmission 10 includes a hydraulic pump 12 of variable displacement type which is driven by the main shaft 8, a hydraulic motor 14 of variable displacement type which is connected to the generator 20, and a high pressure oil line and a low pressure oil line which are arranged between the hydraulic pump 12 and the hydraulic motor 14. The hydraulic transmission 10 is at least partially constituted of a plurality of modules (M1 to M7).

Abstract: An object of the present invention is to provide a wind turbine generator and a tidal current generator equipped with a hydraulic transmission with a combination of a hydraulic pump and a hydraulic motor and which has a superior productivity and maintainability. The wind turbine generator 1 has the hydraulic transmission 10 for transmitting the rotation energy of a main shaft 8 to a generator 20. The hydraulic transmission 10 includes a hydraulic pump 12 of variable displacement type which is driven by the main shaft 8, a hydraulic motor 14 of variable displacement type which is connected to the generator 20, and a high pressure oil line and a low pressure oil line which are arranged between the hydraulic pump 12 and the hydraulic motor 14. The hydraulic transmission 10 is at least partially constituted of a plurality of modules (M1 to M7).

Abstract: An infinitely variable transmission for use with an internal combustion engine is provided. Specifically, a prime mover is provided for driving a first hydraulic machine. The first hydraulic machine is arranged to drive a second hydraulic machine via a fluid line that connects the first and second hydraulic machines. The second hydraulic machine is operatively connected with an output element, such as a wheel to drive a vehicle. Each of the first and second hydraulic machines have electronically controllable valves for varying the speed and/or the torque of the first and second hydraulic machines thereby providing an infinitely variable transmission.

Abstract: A fluid-working machine has a plurality of working chambers, e.g. cylinders (11), of cyclically changing volume, a high-pressure fluid manifold (14) and a low-pressure fluid manifold (16), at least one valve (13, 15) linking each working chamber to each manifold, and electronic sequencing means (20) for operating said valves in timed relationship with the changing volume of each chamber (11), wherein the electronic sequencing means is arranged to operate the valves of each chamber in one of an idling mode, a partial mode in which only part of the usable volume of the chamber is used, and a full mode in which all of the usable volume of the chamber (11) is used, and the electronic sequencing means (20) is arranged to select the mode of each chamber on successive cycles so as to infinitely vary the time averaged effective flow rate of fluid through the machine.

Abstract: A valve assembly (1) operable to allow or prevent the flow of fluid to or from a working chamber of a fluid-operated machine, comprising radially spaced apart inner and outer annular valve seats (8, 15) defining an annular passage therebetween, a valve member comprising a sealing ring (21), and means (3, 7, 26, 25) for moving the valve member axially between a first position in which the sealing ring (21) is in seating engagement with the annular valve seats to close the annular passage to fluid flow therethrough and a second position in which the sealing ring (21) is spaced from the annular valve seats (8, 15) so that the annular passage is open to fluid flow therethrough. The valve assembly further comprises axially spaced apart first and second valve guide means (6) for guiding the valve member during axial movement between its first and second positions.