Linear Technologies is primarily a technology developer and it is ultimately up to the licensees of the technology to determine output power and sizing appropriate for the market.
The following are points to consider when designing for a particular output power.
The main change to the implementation of the LWG as the power increases is the move away from using a castor angle and cowlings to a solution with no cowlings and axels that are positioned independently by yaw motors.
The output power of the LWG (for a particular wind speed) can be increased by:
- Increasing the length of the blades. Power is increased proportionately i.e. 25% longer blades will give 25% more power. This is easily achieved when extrusion techniques are employed. (Longer blades would require an increase in wall thickness)
- Increasing the number of blades. Power is increased proportionately i.e. 25% more blades will give 25% more power. This requires the cables to be longer and additional blades to be fitted. The pulley ends are spaced appropriately further apart. (Loading on the axel bearings would need to be checked)
The process of converting wind energy to mechanical energy is more efficient when the blade to wind speed ratio is increased. In other words it is better to have fewer blades that travel at higher speed.
OPERATING WIND SPEED
The LWG can operate over a wide wind speed range because the blades can be angled optimally for any wind speed. Also the guy wire support structure will permit higher wind speed operation before the need to spill wind.
Low wind speeds that blow constantly can be accommodated by populating the LWG with many, larger area blades that will allow the machine to operate with high blade solidity. The LWG rotates slower but has higher torque. Although the energy in low wind speeds is small, when accumulated over time, considerable kWH can result.
Medium to high wind speeds are accommodated by populating the LWG with fewer and smaller area blades that will allow the machine to operate with low blade solidity. The LWG rotates faster but with lower torque. Because of the higher blade speed, wind energy is converted more efficiently.
Click the thumbnails for enlarged images.