Abstract: An injection molding system, water jet cutting machine or other industrial system has a synthetically controlled variable displacement fluid working machine which outputs hydraulic fluid to one or more fluid consumers, such as rams or hydraulic motors, through hydraulically stiff fluid retaining volumes and receives hydraulic fluid back from one or more fluid consumers through the same or other said hydraulically stiff fluid retaining volumes. Individual piston cylinder assemblies can be allocated to different outputs. There may be no valve between the machine and the consumers. A working chamber of the machine can be caused to undergo a motoring cycle to enable the machine to output more power than is received from a motor driving the machine. An accumulator can be used to provide a source of hydraulic compliance. The machine can be controlled using pressure control, flow control, feed forward control or variable power/variable power limit control.

Abstract: An injection moulding system, water jet cutting machine or other industrial system has a synthetically controlled variable displacement fluid working machine which outputs hydraulic fluid to one or more fluid consumers, such as rams or hydraulic motors, through hydraulically stiff fluid retaining volumes and receives hydraulic fluid back from one or more fluid consumers through the same or other said hydraulically stiff fluid retaining volumes. Individual piston cylinder assemblies can be allocated to different outputs. There may be no valve between the machine and the consumers. A working chamber of the machine can be caused to undergo a motoring cycle to enable the machine to output more power than is received from a motor driving the machine. An accumulator can be used to provide a source of hydraulic compliance. The machine can be controlled using pressure control, flow control, feed forward control or variable power/variable power limit control.

Abstract: A fluid-working machine for a renewable energy generation device, the fluid-working machine comprising a ring cam and a plurality of working chambers, the ring cam having an annular working surface extending around an axis of rotation of the ring cam, the annular working surface defining a plurality of waves, each working chamber having a piston, each piston in operative engagement with the ring cam working surface, the ring cam and working chambers being mounted to rotate relative to each other, cycles of working chamber volume being thereby coupled to rotation of the ring cam relative to the working chambers, characterized in that the individual waves of the ring cam working surface have an asymmetric profile.

Abstract: A fluid-working machine for a renewable energy generation device, the fluid-working machine comprising a ring cam and a plurality of working chambers, the ring cam having an annular working surface extending around an axis of rotation of the ring cam, the annular working surface defining a plurality of waves, each working chamber having a piston, each piston in operative engagement with the ring cam working surface, the ring cam and working chambers being mounted to rotate relative to each other, cycles of working chamber volume being thereby coupled to rotation of the ring cam relative to the working chambers, characterised in that the individual waves of the ring cam working surface have an asymmetric profile.

Abstract: A fluid-working machine for a renewable energy generation device, the fluid-working machine comprising a ring cam and a plurality of working chambers, the ring cam having an annular working surface extending around an axis of rotation of the ring cam, the annular working surface defining a plurality of waves, each working chamber having a piston, each piston in operative engagement with the ring cam working surface, the ring cam and working chambers being mounted to rotate relative to each other, cycles of working chamber volume being thereby coupled to rotation of the ring cam relative to the working chambers, characterised in that the individual waves of the ring cam working surface have an asymmetric profile.

Abstract: A fluid working machine, operable to carry out a motoring cycle under at least some circumstances, comprises a controller (12) and a working chamber (2) of cyclically varying volume. The working chamber has a high pressure valve (18) associated therewith to control the connection of the working chamber to a high pressure manifold (20), and an electronically controllable primary low pressure valve (14) to control the connection of the working chamber to a low pressure manifold. The controller is operable to actively control at least the primary low pressure valve, in phased relationship to cycles of working chamber volume, to determine the net displacement of fluid by the working chamber on a cycle by cycle basis. The fluid working machine is adapted to release pressurised fluid from the working chamber prior to the opening of the primary low-pressure valve, during a motoring cycle. This facilitates the opening of the primary low pressure valve.