Linear drive apparatus and method of controlling and using same for solar energy tracking

A linear drive apparatus, comprising:

• an outer tube;
• a sealing end cap provided at the end of the outer tube;
• a screw provided in the outer tube, one end of the screw connected to a drive mechanism;
• a drive nut provided on the screw in a threaded fit therewith;
• an extension rod provided between the outer tube and the screw, one end of the extension rod connected to the drive nut and the other end thereof passing through the sealing end cap;
• a sealing assembly provided between the extension rod and the sealing end cap;
• and
• a waterproof and oil-proof ventilation stopper is provided on the outer tube.

The linear drive apparatus of claim 1, further comprising:

• a single-row tapered roller bearing provided correspondingly in the outer tube and at connection ends between the screw and the drive mechanism;
• an outer ring of said single-row tapered roller bearing connected to an inner wall of the outer tube;
• an inner ring closely fitted with the screw;
• and
• a sliding bearing provided between the extension rod and the sealing end cap.

A method for controlling solar tracking with a linear drive apparatus, comprising the following steps:

• a) determining solar tracking orientation through a controller of a solar tracker firstly, and then determining the current solar angles P1 in different periods through the solar tracking orientation;
• b) comparing the current solar angle PI with the initial angle P0 of the solar tracker to judge whether the current linear drive apparatus is needed to act, wherein the initial angle of the solar tracker is determined by structure design;
• c) calculating the number M of pulses tracked this time by a processor according to the current solar angle P1 and the initial angle P0 of the solar tracker, and controlling a motor in the linear drive apparatus to rotate according to the number M of the pulses, if the linear drive apparatus is needed to act;
• and
• d) sending to a driver a signal tracked and rotated this time by the processor, driving the motor in the linear drive apparatus to act by the driver after the driver receives a control signal, and determining whether the linear drive apparatus extends or shortens based on the positive-negative voltage of the motor input by the driver.