Mass inerter for solar trackers
A solar tracking system includes a pier, a torque tube rotatably supported on the pier, a solar module coupled to the torque tube, wherein rotation of the torque tube effectuates a corresponding rotation of the solar module, and an inerter, the inerter including a drive gear couplable to the torque tube, wherein rotation of the torque tube effectuates movement of the drive gear, a drive gear operably coupled to the drive gear, wherein movement of the drive gear effectuates movement of the driven gear, and a flywheel operably coupled to the driven gear, wherein movement of the driven gear effectuates rotation of the flywheel, wherein a wind loading on the solar module effectuates rotation of the torque tube and a corresponding rotation of the flywheel, where rotation of the flywheel stores kinetic energy to mitigate excitation of the solar tracker.
1 . A solar tracking system, comprising:
a pier;
a torque tube rotatably supported on the pier;
a solar module coupled to the torque tube, wherein rotation of the torque tube effectuates a corresponding rotation of the solar module; and
an inerter, the inerter including:
a drive mechanism operatively coupled to the torque tube, wherein rotation of the torque tube effectuates movement of the drive mechanism;
a driven mechanism operably coupled to the drive mechanism, wherein movement of the drive mechanism effectuates movement of the driven mechanism; and
a flywheel operably coupled to the driven mechanism and configured to store and release kinetic energy, wherein movement of the driven mechanism effectuates rotation of the flywheel, wherein a ratio of the drive mechanism to the driven mechanism is greater than 1:1 such that the drive mechanism is configured to cause the driven mechanism and the flywheel to move faster than the movement of the drive mechanism, wherein the inerter is configured such that, when the torque tube is rotated in a first direction, the driven mechanism causes the flywheel to rotate and store kinetic energy, and wherein the inerter is configured such that, when a wind loading on the solar module effectuates rotation of the torque tube in a second, opposite direction, the flywheel is configured with a moment of inertia and stored kinetic energy to resist rotation of the torque tube in the second direction to mitigate excitation of the solar tracking system.
2 . The solar tracking system according to claim 1 , wherein the drive mechanism is a drive gear and the driven mechanism is a driven gear.
3 . The solar tracking system according to claim 2 , wherein the ratio is a gear ratio, and wherein the gear ratio of the drive gear to the driven gear is greater than 1:1.
4 . The solar tracking system according to claim 2 , wherein the drive gear defines a sector profile having an arcuate side surface, the arcuate side surface defining a plurality of teeth engageable with the driven gear.
5 . The solar tracking system according to claim 2 , wherein the drive gear is a gear rack, wherein linear motion of the gear rack effectuates movement of the driven gear via a gear train.
6 . The solar tracking system according to claim 2 , wherein the drive gear is a ball screw and the flywheel is a ball screw nut, wherein linear motion of the ball screw effectuates rotation of the ball screw nut.
7 . The solar tracking system according to claim 1 , further comprising a plurality of gears, the plurality of gears in mechanical communication with the drive mechanism and the flywheel, such that rotational speed of the flywheel is greater than a rotational speed of the drive mechanism.
8 . The solar tracking system according to claim 2 , wherein the driven gear is supported on the pier.
9 . The solar tracking system according to claim 1 , wherein the flywheel is rotatably supported on the pier.