Wind Turbine Torque Converter for Constant Speed Output
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Wind turbines face challenges in providing a constant input angular velocity to generators due to varying wind speeds, leading to grid code compliance issues and operational complexities with conventional variable speed magnetic couplings that rely on grid power.
Innovation Solution
A system comprising an electrical machine, torque converter, and electrical converters that convert rotary mechanical power to electrical power and back to mechanical power, maintaining a constant speed mechanical output for the synchronous generator, independent of grid power.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a variable speed magnetic coupling is used to provide constant input angular velocity to the generator, then the generator operation efficiency is improved, but grid code compliance issues arise and operational complexities increase
Solution Approach 1:
The patent applies dynamics by using a variable speed magnetic coupling that can dynamically adjust its operating speed to match the varying wind turbine rotor speed while maintaining constant speed output to the generator. This dynamic adaptation allows the system to handle variable input conditions while ensuring efficient generator operation, resolving the contradiction between productivity improvement and operational complexity.
Solution Approach 2:
The variable speed magnetic coupling acts as an intermediary device between the wind turbine rotor and the generator. It mediates the speed variation by absorbing the speed differences through its variable speed capability, thereby protecting the generator from direct exposure to variable speed conditions while maintaining efficient operation. This intermediary function reduces operational complexities by isolating the generator from grid code compliance issues.
2Speed
If a variable speed magnetic coupling withdraws electrical power directly from the grid, then the constant input angular velocity is maintained, but grid code compliance issues result in complexities and expense
Solution Approach 1:
The variable speed magnetic coupling is designed to be self-sufficient by drawing power from the wind turbine's own mechanical output rather than requiring external grid power. This self-service approach eliminates the need for complex grid code compliance measures and associated expenses, while still maintaining the ability to provide constant input angular velocity to the generator through its internal variable speed control mechanism.
Solution Approach 2:
The patent extracts the power requirement for the variable speed magnetic coupling from the external grid and replaces it with power derived from the wind turbine's own mechanical output. This extraction eliminates the problematic dependency on grid power and the associated compliance complexities, while preserving the speed control functionality needed to maintain constant angular velocity input to the generator.
3Device complexity
If the rotatable shaft directly connects to the generator, then the system simplicity is maintained, but the constant input angular velocity requirement cannot be met due to varying wind speeds
Solution Approach 1:
The patent introduces dynamics into the otherwise simple direct connection system by incorporating a variable speed magnetic coupling that can adapt its speed characteristics. This dynamic component allows the system to maintain simplicity in terms of mechanical connection while achieving the necessary speed regulation to meet generator efficiency requirements, effectively resolving the contradiction between system simplicity and productivity.
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 provides a constant angular velocity to the output shaft of a wind turbine, enabling efficient operation of synchronous generators while avoiding grid code compliance issues and reducing operational expenses.
Implementation Method 1
The electrical machine converts rotary mechanical power received from an input shaft to a machine electrical power
Implementation Method 2
The alternate current power is transmitted to the torque converter that converts the alternate current power to an auxiliary mechanical power
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A system to provide constant speed mechanical output in a wind turbine is provided. The system includes at least one electrical machine (34) configured to convert a rotary mechanical power received from a main gear to a machine electrical power. The system further includes one or more electrical converters (36) electrically coupled to the machine and configured to convert the machine electrical power from a direct current (DC) power to an alternate current (AC) power or from the alternate current (AC) power to the direct current (DC) power, where the converters generate a differential electrical power. A torque converter (42) is electrically coupled to the electrical converters (36) and generates a constant speed mechanical output employing the differential electrical power received from the one or more electrical converters.