US20100165494A1

US20100165494A1 - System for asynchronous remote steering of reflectors

Info

Publication number: US20100165494A1
Application number: US12/318,579
Authority: US
Inventors: Jihad Hassan Al-Sadah
Original assignee: King Fahd University of Petroleum and Minerals
Current assignee: King Fahd University of Petroleum and Minerals
Priority date: 2008-12-31
Filing date: 2008-12-31
Publication date: 2010-07-01
Also published as: US8256911B2; US20110211269A1

Abstract

The system for asynchronous remote steering of reflectors has parallel asynchronous remote steering mechanisms operably connected to reflectors. A powerless (mechanical) focal beam brake is also provided. In addition to the powerless focal beam brake, a plurality of safety mechanisms are employed. Remote angle checking is provided to adapt the system for solar thermal power plants, solar furnaces, or the like.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention
The present invention relates to solar reflectors, and more particularly to a system for asynchronous remote steering of solar reflectors.
2. Description of the Related Art
Solar radiation is conceived as a renewable source of energy that is free, abundant and spatially distributed. Since solar radiation is not sufficiently concentrated, many optical methods of concentrating solar energy have been proposed. Some of the large scale concentration methods (e.g. solar thermal power plants) rely on flat surfaces that track the sun's position to reflect the direct component toward a designated target. The cost of this technology is proportional to the number of reflectors, as each reflector requires two rotating motors and two tilt sensors.
The solar reflectors should be arranged in rows and should be steered so that the reflected light from all the reflectors results in a focal point, concentrating the solar energy in a small area to do thermal/electric work.
While it seems logical to have a dedicated couple of motors per reflectors, the economic sense is against it. One way is to enlarge the reflecting area per the rotation mechanism. However, there is a limit, and often the area of a reflector should be small to simulate a concave reflector in some applications. This entails having two motors and two sensors per reflector, as there are two steered rotations required.
Thus, a system for asynchronous remote steering of reflectors solving the aforementioned problems is desired.

SUMMARY OF THE INVENTION

The system for asynchronous remote steering of reflectors has parallel asynchronous remote steering mechanisms operably connected to reflectors. A powerless (mechanical) focal beam brake is also provided. In addition to the powerless focal beam brake, a plurality of safety mechanisms are employed. Remote angle checking is provided to adapt the system for solar thermal power plants, solar furnaces, or the like.
These and other features of the present invention will become readily apparent upon further review of the following specification and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic view of a system for asynchronous remote steering of reflectors according to the present invention.

FIG. 2 is a diagrammatic view showing the central box wheels of a system for asynchronous remote steering of reflectors according to the present invention.

Similar reference characters denote corresponding features consistently throughout the attached drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention includes parallel asynchronous remote steering mechanisms operably connected to reflectors. A powerless (mechanical) focal beam brake is also provided. In addition to the powerless focal beam brake, a plurality of safety mechanisms are employed. Remote angle checking is provided to adapt the system for solar thermal power plants, solar furnaces, or the like.
As shown in FIGS. 1 and 2, the system connects each mirror (reflector) 15 by cables, belts or strings 25 and pulley wheels 20 to a central electromechanical box comprising brake/unbrake motor 30, rotator motor 45 and mirror selection motor 40. As shown in FIG. 2, each mirror (reflector) 15 has a pair of driven wheels 20 that are connected to drive wheels 210 and 200, respectively, within the central box by the cables or strings 25. Each mirror is rotated by pulling a string in a desired direction within the central box, then actuating a powerless motion brake. The rotator motor 45 subsequently moves to the rest of the mirrors 15 sequentially, i.e., asynchronously, updating the direction of each mirror 15 in the array of mirrors 15.
The direction and magnitude of string motion corresponds to a computed exact tilt change and is logged within a computer that controls the system. The mechanical connection may not be perfect. Hence, calibration of the system may be accomplished by remote laser orientation measurement. Each mirror rotation mechanism is represented by a wheel 20 in a bank of wheels that are locked by a mechanical brake, e.g., a powerless (mechanical) spring-biased braking system.
The rotator motor 45 passes by each wheel 20, releases the brake motor 30, rotates the wheel 20, and then reapplies the brake motor 30. Braking motor 30, rotator motor 45, and selection motor 40 are interoperably connected to move the steering assembly along the bank of wheels to perform a reflector steering task. As most clearly shown in FIG. 2, a tension keeping spring 205 is disposed along the connection of central box drive wheel 200 (connected to braking motor 30) to driven wheel 20 on the mirror 15. Drive wheel 210 (connected to rotator motor 45) in the central box completes the connection via connection string/cable 25 to driven wheel 20.
It should be understood that each mirror 15 does not have a dedicated motor, but has a mechanical connection through strings 25 to a central rotation motor 45, thus amounting to cost savings and reduced maintenance.
One safety mechanism system ensures the breaking up of the focus in case of emergency. This is done by making each mirror's resting position (minimum energy position by, say, springs) different from the rest. In case of safety activation, a rod stops the work of all the brakes of individual mirrors, and each one goes to a predetermined non-focusing rotational position. This is sufficient to kill the concentration of the mirrors and avoid accidents, if needed.
It is to be understood that the present invention is not limited to the embodiment described above, but encompasses any and all embodiments within the scope of the following claims.

Claims

1. A system for asynchronous remote steering of reflectors, comprising:

a plurality of reflectors, each of the reflectors having a first driven wheel connected thereto operable to adjust and angle of rotation of the reflector and a second driven wheel connected thereto to brake adjustment of the angle of rotation;

a plurality of rotator drive wheels mechanically connected to the first driven wheels of the reflectors;

a plurality of brake drive wheels mechanically connected to the second driven wheels of the reflectors;

a braking motor;

a rotator motor; and

means for sequentially engaging the rotator motor and the braking motor to the rotator and brake drive wheels for one of the reflectors after is another.

2. The system for asynchronous remote steering of reflectors according to claim 1, wherein said sequentially engaging means comprises a reflector selection motor interoperably connected to the rotator motor and the braking motor.

3. The system for asynchronous remote steering of reflectors according to claim 1, further comprising a bias spring mechanically connected between each of the brake drive wheels and the brake driven wheels.

4. The system for asynchronous remote steering of reflectors according to claim 1, wherein said sequentially engaging means further comprises a computer controlling said rotator and braking motors to control adjustment of the tilt angle of each of said reflectors.

5. The system for asynchronous remote steering of reflectors according to claim 1, further comprising a system calibrator.

6. The system for asynchronous remote steering of reflectors according to claim 5, wherein the system calibrator comprises a remote laser orientation measuring system.

7. The system for asynchronous remote steering of reflectors according to claim 1, wherein a resting position of each individual reflector is unique with respect to the remaining reflectors.

8. The system for asynchronous remote steering of reflectors according to claim 7, further comprising means for stopping work of all the brakes of the individual reflectors, wherein each reflector goes to a pre-determined non focusing rotational position.