Hydrokinetic Turbine Torque Control Without Gearboxes or Towers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current hydrokinetic turbine systems are costly, inefficient, and require frequent maintenance due to high energy density limitations, mechanical wear, and the need for heavy gearboxes and fixed towers, which restrict their operational flexibility and cost-effectiveness.
Innovation Solution
The implementation of a hydrokinetic turbine-generator system that uses electronic torque control to balance residual torque, eliminates the need for high-speed generators, and positions direct-drive, variable-speed DC power generation components outside the turbine body, allowing for single-point mooring and dynamic positioning of turbines to optimize energy capture across varying water flow conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If a gearbox and high-speed generator are used to transmit power efficiently, then the generator can operate at optimal speed, but the system weight increases and requires a fixed tower for support
Solution Approach 1:
The patent removes the gearbox and high-speed generator from the system, replacing them with a direct-drive, variable-speed DC generator. This extraction of the mechanical transmission components eliminates the need for a fixed tower while maintaining power generation capability through electronic torque control
Solution Approach 2:
The patent replaces the mechanical gearbox-transmission system with an electronic control system that dynamically adjusts torque on the generator. This substitution eliminates mechanical wear and reduces system weight while achieving the same power transmission function through electronic means
2Force
If a fixed tower with swivel connection is used to support the turbine, then the tower can offset reaction torque and support the heavy generator, but the system cost and complexity increase
Solution Approach 1:
The patent removes the fixed tower and swivel connection from the system. Instead of mechanically supporting and orienting the turbine, the system uses electronic torque control to dynamically balance reaction torque, allowing the turbine to be suspended from a single point mooring
Solution Approach 2:
The patent replaces the mechanical tower-support system with an electronic control system that actively manages torque. The swivel connection's orientation function is replaced by electronic adjustment of generator torque to align the turbine with water flow direction
3Ease of manufacture
If a single-point mooring is used to reduce cost, then the system becomes less expensive, but the system cannot offset reaction torque
Solution Approach 1:
The patent replaces the mechanical torque-offsetting mechanism with an electronic control system. The single-point mooring is retained for cost savings, while electronic torque control dynamically balances reaction torque, eliminating the need for mechanical counterbalancing structures
4Adaptability or versatility
If long blades on a small body are used to capture low-velocity water flow, then the turbine can operate in low-energy density flows, but the rotational speed is too low for efficient power generation
Solution Approach 1:
The patent eliminates the mechanical gearbox that was needed to convert low rotational speed to high generator speed. Instead, the direct-drive variable-speed DC generator with electronic torque control can efficiently generate power across a wide range of rotational speeds, including the lower speeds produced by long blades in low-velocity flow
5Ease of operation
If mechanical components like gearboxes and swivels are used, then the system can transmit power and allow turbine alignment, but frequent maintenance is required due to mechanical wear
Solution Approach 1:
The patent replaces mechanical alignment mechanisms with electronic torque control. The generator's electromagnetic torque can be dynamically adjusted to align the turbine with the water flow direction, eliminating mechanical wear from swivels and gearboxes while maintaining alignment capability
Solution Approach 2:
The patent removes mechanical transmission components like gearboxes and their associated lubrication and maintenance systems. The direct-drive generator eliminates the need for mechanical power transmission, reducing maintenance requirements
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution reduces the weight and cost of the system, enhances operational efficiency, and enables flexible deployment and maintenance by eliminating the need for steering vanes and gearbox transmissions, while maintaining high efficiency across different water flow velocities and directions.
Implementation Method 1
A plurality of turbine blades (17, 3) are positioned about and attached to rotors (15, 2) to rotate the rotors in response to water flow (4)
Implementation Method 2
Direct-drive, variable-speed direct-current (DC) power-generation components outside of the turbine-generator body
Data Source
AI summary
In a hydrokinetic turbine-generator system having more than one turbine-generators aligned into a water stream for conversion of hydrokinetic energy to electrical energy, the improvement wherein the more than one turbine-generators are direct-drive electrical generators configured to control generator current such that residual torque on the system is balanced using electronic torque control.