Methods, systems, and devices are disclosed for wave power generation. In one aspect, a wave power generator device includes a stator assembly and a rotor assembly encased within a tube frame. The stator assembly includes an array of inductor coils in a fixed position within a cavity of the tube frame and a plurality of bearings coupled to the tube frame. The rotor assembly includes a turbine rotor having a central hub and peripheral blades coupled to a high inertia annular flywheel that is moveably engaged with the bearings of the stator assembly, and an array of magnets arranged to be evenly spaced and of alternating axial polarity from one another extending from the annular flywheel into the cavity between the array of inductor coils, such that electric currents are produced based on magnetic field interaction of the magnets with the inductor coils during the rotation of the annular flywheel.

The invention concerns a method for coupling a hydroelectric power plant in a turbine mode to a grid, in order to generate power for a grid, said hydroelectric power plant comprising at least a first hydroelectric unit (10) and a second hydroelectric unit (100), each provided with a runner (6) mechanically coupled to a shaft line (8) and to a generator, a distributor (4) comprising guide vanes to control a flow of water to said runner, said hydroelectric power plant further comprising a variable frequency drive (20), the method comprising: a) starting the rotation of at least said first hydroelectric unit (10) and said second hydroelectric unit (100); b) connecting the variable frequency drive (20) to the generator of the first hydroelectric unit (10) and to the grid and stabilizing the speed of the first hydroelectric unit c) connecting the first hydroelectric unit (10) to the grid and disconnecting the generator of the first hydroelectric unit from the variable frequency drive (20); d) connecting said variable frequency drive (20) to the generator of the second hydroelectric unit (100) and to the grid and stabilizing the speed of the second. hydroelectric unit; e) connecting the second hydroelectric unit (100) to the grid and disconnecting the generator of the second hydroelectric unit from said variable frequency drive (20).

The invention relates to a method and a system for adjusting the torque of a mass and spinning wheel rotator in a wave power plant. The torque of a rotator rotating around a vertical shaft is compensated partially or completely with a compensating moment which is produced by an electric machine. Acceleration components (.sup.ACCx and .sup.ACCy) are measured for a given point of the wave power plant's floating body (1) in directions perpendicular to each other. A vector (V.sub.xy) with a magnitude formula (A) and a direction (a.sub.Acc) is established for said acceleration components, the direction or angular position (a) of a rotator (2) is monitored and its lag (α.sub.LAG) from the acceleration vector's direction (α.sub.Acc) is determined. The compensating moment is adjusted as dependent on a compensation factor (B) whose sub-factors are the magnitude of the body's acceleration vector (V.sub.xy) and the sine of the angle of lag (sin α.sub.LAG). This is supplemented with a compensation factor based on spinning wheel forces in a manner otherwise similar except that the acceleration must be replaced with a rotation speed (AV.sub.x-y) of the body's inclination, which is obtained from an inertial sensor 821). and the mass must be replaced with a gyro force which is dependent on the inertia and rotating speed of a spinning wheel.

The invention relates to a method and a system for adjusting the torque of a mass and spinning wheel rotator in a wave power plant. The torque of a rotator rotating around a vertical shaft is compensated partially or completely with a compensating moment which is produced by an electric machine. Acceleration components (.sup.ACCx and .sup.ACCy) are measured for a given point of the wave power plant's floating body (1) in directions perpendicular to each other. A vector (V.sub.xy) with a magnitude formula (A) and a direction (a.sub.Acc) is established for said acceleration components, the direction or angular position (a) of a rotator (2) is monitored and its lag (α.sub.LAG) from the acceleration vector's direction (α.sub.Acc) is determined. The compensating moment is adjusted as dependent on a compensation factor (B) whose sub-factors are the magnitude of the body's acceleration vector (V.sub.xy) and the sine of the angle of lag (sin α.sub.LAG). This is supplemented with a compensation factor based on spinning wheel forces in a manner otherwise similar except that the acceleration must be replaced with a rotation speed (AV.sub.x-y) of the body's inclination, which is obtained from an inertial sensor 821). and the mass must be replaced with a gyro force which is dependent on the inertia and rotating speed of a spinning wheel.

A startup method of a Francis turbine according to an embodiment includes: a first rotation-speed increasing step in which a rotation speed of the runner is increased by opening the guide vane at a first opening; a second rotation-speed increasing step in which the increase in the rotation speed of the runner is accelerated by opening the guide vane at a second opening that is larger than the first opening after the first rotation-speed increasing step; and a rotation-speed regulating step in which the rotation speed of the runner is regulated to a rated rotation speed by opening the guide vane at a no-load opening after the second rotation-speed increasing step. The first opening is an opening that is half or less than the no-load opening.

Systems and methods for a WEC controller that uses a self-tuning proportional-integral control law prescribing motor torques to maximize electrical power generation and automatically tune the controller to maximize power absorption. In an embodiment, the controller may be part of any resonant WEC system. The control law relies upon an identified model of device intrinsic impedance to generate a frequency-domain estimate of the wave-induced excitation force and measurements of device velocities. The control law was tested in irregular sea-states that evolved over hours (a rapid, but realistic time-scale) and that changed instantly (an unrealistic scenario to evaluate controller response).

Systems and methods for a WEC controller that uses a self-tuning proportional-integral control law prescribing motor torques to maximize electrical power generation and automatically tune the controller to maximize power absorption. In an embodiment, the controller may be part of any resonant WEC system. The control law relies upon an identified model of device intrinsic impedance to generate a frequency-domain estimate of the wave-induced excitation force and measurements of device velocities. The control law was tested in irregular sea-states that evolved over hours (a rapid, but realistic time-scale) and that changed instantly (an unrealistic scenario to evaluate controller response).

A wave energy capture system deployed in water converts mechanical motion induced by waves in the water to electrical energy. A controller of the wave energy capture system receives input regarding real-time wave conditions in a vicinity of the wave energy capture system. The controller applies a control model to the received input to select a value of a control parameter for the wave energy capture system, where the control model includes a model that has been trained using machine learning to take wave condition data as input and to output control parameter values selected based on the wave condition data in order to increase an amount of energy captured by the wave energy capture system. The controller implements the selected value of the control parameter on the wave energy capture system.

A wave energy capture system deployed in water converts mechanical motion induced by waves in the water to electrical energy. A controller of the wave energy capture system receives input regarding real-time wave conditions in a vicinity of the wave energy capture system. The controller applies a control model to the received input to select a value of a control parameter for the wave energy capture system, where the control model includes a model that has been trained using machine learning to take wave condition data as input and to output control parameter values selected based on the wave condition data in order to increase an amount of energy captured by the wave energy capture system. The controller implements the selected value of the control parameter on the wave energy capture system.

An aquifer storage and recovery system can include a pump, an electric motor coupled to the pump, a drive unit configured to control operation of the electric motor, and a controller. The controller can be configured to flow water into a well bore from a source reservoir through the pump such that the pump rotates in a reverse direction and drives the electric motor coupled to the pump in the reverse direction to operate as a generator, determine a power output of the electric motor, determine a difference between the power output of the electric motor and a power output set point, and operate the drive unit to control a rotational speed of the electric motor based at least in part on the difference between the power output of the electric motor and the power output set point.