Tower 70 meter Hub Height with Simple-Two Section Tower
The N1000 obtains a 70m hub height using only two tower sections. Advanced analytical techniques are used to dynamically tune the tower/nacelle/blade system during the engineering design process in order to optimize the system weight and reliability. Smaller foundations, fewer trucks onsite and at least one less crane pick per turbine combine to provide installed costs which are comparatively favorable for the N1000.
Gearbox / Drivetrain
A key component of turbine reliability is gearbox survivability. N1000’s have never had a gearbox problem. Furthermore, N1000 gearboxes show exceptionally low wear, even after many years of operation. Multiple factors in the overall design reduce gearbox loading:
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Two blades are lighter. |
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The blade teeter-hub dissipates loads before they reach the gearbox. |
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Integration of the main drive shaft bearings into the gearbox design |
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A robust, single cylindrical housing (torque tube) locks the gearbox, drive shaft and generator into one load-absorbing unit. |
Torque Tube and Unibody Drivetrain
Nordic utilizes a torque tube mounting structure between the gearbox and generator . The torque tube is a light-weight, yet robust cylindrical structure that holds the gearbox and generator in alignment. The torque tube is very efficient structurally and maintains alignment to very tight tolerances. This arrangement contributes significantly to the exceptional reliability experienced to date on the gearbox and bearing. In comparison, most utility-scale turbines employ a heavy, cast baseplate on which the hub, gearbox and generator drivetrain elements are mounted separately.
Dissipative Drivetrain Mounts
The connection between the drivetrain and the bed is achieved through flexible, load dampening mounts rather than hard mounts. These flexible, dampening mounts are possible because the drive train is held in close alignment by the torque tube. The dampening mounts lessen the vibration loads transferred to the bed, tower and foundation thereby reducing fatigue loads and noise.
Simple and Proven Generator Technology
The Nordic turbine’s electrical system incorporates an induction generator with soft start and power factor correction. This system is proven to be highly reliable, simple and cost effective, particularly when compared with complex electrical converters and other new generator technologies used on utility-scale wind turbines today.