초록 ▼

A method is described of controlling a tethered, underwater, water current-driven turbine, power-generating device. A predetermined maximum depth and a predetermined minimum depth are set. In response to sensing depth of the device, an ascend protocol or a descend protocol are selectively invoked. T

A method is described of controlling a tethered, underwater, water current-driven turbine, power-generating device. A predetermined maximum depth and a predetermined minimum depth are set. In response to sensing depth of the device, an ascend protocol or a descend protocol are selectively invoked. These protocols maintain an operating depth of the device that is midway between the predetermined maximum depth and the predetermined minimum depth. The turbine includes variable-pitch rotor blades. A maximum allowable drag force load on the turbine rotors is selected. The pitch of the variable-pitch rotor blades on the turbine is adjusted such that the drag force loading of the device does not exceed a maximum design level.

대표청구항 ▼

[ What is claimed is:] [7.] A method of controlling a tethered underwater device having a lift-producing hydrofoil, an adjustable pitch rotor blade-driven turbine, ballast tanks, and a lift-adjusting mechanism, comprising:A. sensing electrical energy output that is proportional to velocity of water

[ What is claimed is:] [7.] A method of controlling a tethered underwater device having a lift-producing hydrofoil, an adjustable pitch rotor blade-driven turbine, ballast tanks, and a lift-adjusting mechanism, comprising:A. sensing electrical energy output that is proportional to velocity of water current flowing past said device;B. sensing depth of said device;C. providing an initial net ballast to said device resulting in an initial positive buoyancy sufficient to remain above a maximum predetermined depth of said ballast tanks;D. balancing forces on said device by adjusting at least one of the parameters of:i. lift of said hydrofoil with a lift-adjusting mechanism,ii. buoyancy force of said ballast tanks by adjusting the amount of ballast held within said tanks, and,iii. drag force loading on said rotors by adjusting the pitch of said rotor blades, such that said device passively seeks an initial equilibrium velocity of water current, located within a chosen predetermined depth range and wherein the forces on said device are balanced, which when flowing past said device is sufficient to keep said device within said depth range; and,E. upon a condition that said initial equilibrium velocity changes to a new velocity that tends to urge said device out of said depth range, repeating step D to cause said device to operate at a new equilibrium velocity that is within said depth range.