A fluid apparatus includes a hydraulic machine, a rotary electric machine connected to the hydraulic machine, and a power conversion controller that converts power from the rotary electric machine. A non-normal operation is performed in a warning state that differs from a normal state in which a normal operation is continued and an anomalous state in which operation is stopped to continue a stopped condition.

A fluid apparatus includes a hydraulic machine, a rotary electric machine connected to the hydraulic machine, and a power conversion controller that converts power from the rotary electric machine. A non-normal operation is performed in a warning state that differs from a normal state in which a normal operation is continued and an anomalous state in which operation is stopped to continue a stopped condition.

An apparatus energized by a flowing fluid includes at least one turbine blade having a trailing edge angle and an elastic deformation member connected to the at least one turbine blade. The deformation of the elastic deformation member changes an orientation of a trailing edge angle of the at least one turbine blade.

A hydraulic lock apparatus includes a hydraulic actuator, a pressure storage device connected to the hydraulic actuator, and a control valve configured to actuate to a first position and a second position. The control valve fluidly isolates the pressure storage device from the hydraulic actuator when the control valve is in the first position. The control valve fluidly connects the pressure storage device to the hydraulic actuator when the control valve is in the second position.

A hydraulic lock apparatus includes a hydraulic actuator, a pressure storage device connected to the hydraulic actuator, and a control valve configured to actuate to a first position and a second position. The control valve fluidly isolates the pressure storage device from the hydraulic actuator when the control valve is in the first position. The control valve fluidly connects the pressure storage device to the hydraulic actuator when the control valve is in the second position.

A turbine (1) for a conduit comprising a turbine unit (13) including a rotor (3), characterized in that the turbine (1) comprises a speed limiting device for said turbine unit (13), which device comprises at least one flexible element (4) connected to the turbine unit (13), so as to limit the flow rate of the fluid passing through the rotor (3) in order to limit the rotational speed of the rotor (3) of the turbine unit (13).

A turbine (1) for a conduit comprising a turbine unit (13) including a rotor (3), characterized in that the turbine (1) comprises a speed limiting device for said turbine unit (13), which device comprises at least one flexible element (4) connected to the turbine unit (13), so as to limit the flow rate of the fluid passing through the rotor (3) in order to limit the rotational speed of the rotor (3) of the turbine unit (13).

The invention provides a system for the extraction of energy from an underwaterflow stream in a body of water. The system comprises a support frame which comprises a plurality of receptacles for mounting functional modules on the support frame. The plurality of receptacles are arranged to form a horizontally-distributed two-dimensional array on the support frame. The plurality of vertical axis turbine units is configured to be interchangeably mounted in the receptacles.

The invention provides a system for the extraction of energy from an underwaterflow stream in a body of water. The system comprises a support frame which comprises a plurality of receptacles for mounting functional modules on the support frame. The plurality of receptacles are arranged to form a horizontally-distributed two-dimensional array on the support frame. The plurality of vertical axis turbine units is configured to be interchangeably mounted in the receptacles.

A method, system and apparatus for operating a hydraulic turbine. A speed adjustment quantity for the hydraulic turbine and a corresponding change in flow quantity are obtained. A rotation speed of the hydraulic turbine is adjusted based on the speed adjustment quantity. A change ratio of the flow quantity with regard to the speed adjustment quantity is determined based on the speed adjustment quantity and the corresponding change in flow quantity. An adjustment manner in which the rotation speed is further adjusted is determined based on the determined based on the determined change ratio of flow quantity. An adjustment manner in which the rotation speed is further adjusted is determined based on the determined change ratio of flow quantity. It enables the hydraulic turbine to track a maximum efficiency operation point under a given power order and water head in real time at a low cost.