Methods and systems for a heliostat mirror and solar tracker assembly

Abstract

One or more cables are attached to the ring-shaped heliostat tracker assembly to control a position of the heliostat mirror on the ring shaped heliostat tracker assembly by winding the one or more cables with a cable winder spool and a cable unwinder spool. The ring-shaped rail track couples to two or more wheels joined to a structure housing a heliostat mirror. One or more position encoders track the heliostat mirror to indicate a position of the heliostat mirror on the ring-shaped rail track.

1 . An apparatus, comprising:
 a cable-pulley driven ring-shaped heliostat tracker assembly includes at least a ring-shaped rail track, one or more cables, a heliostat mirror, two or more wheels joined to a structure housing the heliostat mirror, a fixed center axis of rotation of the cable-pulley driven ring-shaped heliostat tracker assembly, one or more position encoders to indicate a position of the heliostat mirror on the ring-shaped rail track, and one or more cables attached to any combination of 1) the wheels, 2) the structure or 3) both, as well as attached to a cable winder spool and a cable unwinder spool.   
     
     
         2 . The apparatus of  claim 1 , where the ring-shaped rail track is an elevated ring that is mounted above the ground and a mount also rotates about a horizontal axis of the fixed axis of rotation, normal to the earth's surface, and the elevated ring minimizes ground surface preparation because the posts securing the ring-shaped rail track can be pile driven posts, or concrete caissons, as well environmental disturbance and wildlife disturbance in the ground below the ring-shaped rail track, where the ring-shaped rail track being mounted above the ground on pile-driven posts or concrete caissons, which eliminates a need for leveling the ground underneath the ring-shaped rail track. 
     
     
         3 . The apparatus of  claim 1 , where the multiple wheels physically join with the structure attached to and housing the heliostat mirror, where the multiple wheels couple and attach to the ring-shaped track, and where the structure attaches to the cable and which then gives the structure on the multiple wheels the fixed center axis of rotation. 
     
     
         4 . The apparatus of  claim 1 , where two or more motors, a master winder motor, and a slave unwinder motor drive the one or more cables of the cable-pulley driven ring-shaped heliostat tracker assembly, and movement of a mount by the one or more cables driven by the motors about an azimuth and elevation axes is driven by the cables attached to the mount that rides on the cable pulleys positioned around a circumference of the ring-shaped track and about the structure of the heliostat in the azimuth plane and the cable pulleys in the elevation plane. 
     
     
         5 . The apparatus of  claim 1 , where the heliostat mirror is held in a desired position on the ring-shaped rail track and at a desired rate vector by maintaining equal tension on the one or more cables in both directions around the ring shaped rail track, and is moved about the axis of rotation by winding a first cable onto the cable winder spool from one direction and unwinding the first cable from the cable unwinder spool in the opposite direction. 
     
     
         6 . The apparatus of  claim 1 , where the cable unwinder spool exactly follows the same torque amount required by the cable winder spool, which is also at a same rate by the cable winder spool but maintained equal and opposite in magnitude in order to keep tension in the cables, where the rate and the torque amount maintain a desired position on the ring shaped rail track and a desired shape of the heliostat mirror. 
     
     
         7 . The apparatus of  claim 1 , where the one or more cables attach to a top and a bottom of the heliostat mirror to stabilize both the top and bottom of the heliostat mirror, which makes the entire heliostat tracker assembly more better in withstanding deflection of a position of the heliostat tracker assembly on the ring shaped track due to wind gusts and as well maintain accuracy of the position. 
     
     
         8 . The apparatus of  claim 1 , where the ring shaped rail of the heliostat tracker assembly attaches to posts that anchor the tracker assembly to the ground, and captures a route and a position of the two or more wheel rollers of the heliostat mirror within a known radial track, and the two or more wheels sandwich couple on top and below the ring-shaped rail. 
     
     
         9 . The apparatus of  claim 1 , where the heliostat mirror is constructed with multiple facets with multiple individual optical elements making up a structure of a heliostat mirror, where brackets and fixed shim kits are pre-configured and fabricated to set a canting adjustment for each particular optical element location within the multiple faceted heliostat mirror, and also adapted for each individual heliostat array geographic location and orientation within multiple heliostat array structures within a field of heliostat array structures, and each optical element in the mirrors is canted to accommodate a specific focal length requirement of the multiple faceted heliostat mirror including its focal length based on that multiple faceted heliostat mirror's location in the field of heliostat array structures. 
     
     
         10 . The apparatus of  claim 1 , where the two or wheels sandwich coupling on top and below the ring-shaped rail are convex in shape, the ring-shaped rail is constructed of round tubing, and the wheels' shape conforms to rotationally to match a shape of the ring shaped rail. 
     
     
         11 . The apparatus of  claim 1 , where the ring-shaped rail is constructed of an I-beam, and an outside rail structure of the ring shaped rail houses the two or more wheels, which structurally join to the structure housing the heliostat mirror to create the centered axis of rotation for the ring-shaped rail. 
     
     
         12 . The apparatus of  claim 1 , where each pair of wheels of the two or more wheels is held securely to the ring-shaped rail by a mechanism that draws the pair of wheels against the ring shaped rail, where this mechanism is one or more of 1) a force spring loaded mechanism, 2) an inverse gas shock, and 3) a vacuum piston that provides a containment force between the wheels a tube shaped rail to draw the wheels against the tube shaped rail. 
     
     
         13 . The apparatus of  claim 1 , where the heliostat mirror is constructed with multiple facets with multiple individual optical elements making up a structure of a heliostat mirror, where the multiple individual optical elements are individually moveable mirrors that make up a hyperbola shaped for the heliostat mirror, where each mirror facet optical element couples to a drive mechanism to move to change the shape of the heliostat mirror in near real time to better match an angle of the Sun throughout the day as well as throughout the year due to the angle of the Sun in the sky relative to the heliostat mirror on the ground changing both during the day and during different seasons making up a year. 
     
     
         14 . The apparatus of  claim 1 , where the heliostat mirror is constructed with multiple facets with multiple individual optical elements making up a structure of a heliostat mirror, where the multiple individual optical elements are individually moveable mirrors used to compensate for mount deflection due to wind loading, using feedback from accelerometers and position encoders on the heliostat structure. 
     
     
         15 . The apparatus of  claim 13 , where the driven mechanism for the individual optical elements is a gas filled bladder accumulator in a fluid system, an electric motor, a linear actuator, and any combination of the three. 
     
     
         16 . A method for a heliostat tracker assembly, comprising:
 using one or more cables attached to a ring-shaped heliostat tracker assembly to control a position of a heliostat mirror on the ring shaped heliostat tracker assembly by winding the one or more cables with a cable winder spool and a cable unwinder spool;   coupling a ring-shaped rail track to two or more wheels joined to a structure housing a heliostat mirror; and   tracking the heliostat mirror using one or more position encoders to indicate a position of the heliostat mirror on the ring-shaped rail track.   
     
     
         17 . The method of  claim 16 , where the ring-shaped rail track is an elevated ring that is mounted above the ground, and
 rotating a mount about a horizontal axis of a fixed axis of rotation of the ring shaped rail track, normal to the earth's surface.   
     
     
         18 . The method of  claim 16 , further comprising:
 using two or more motors, a master winder motor, and a slave unwinder motor drive the one or more cables of the cable-pulley driven ring-shaped heliostat tracker assembly, and movement of a mount by the one or more cables driven by the motors about an azimuth and elevation axes is driven by the cables attached to the mount that rides on the cable pulleys positioned around a circumference of the ring-shaped track and about the structure of the heliostat in the azimuth plane and the cable pulleys in the elevation plane.   
     
     
         19 . The method of  claim 16 , further comprising:
 holding the heliostat mirror in a desired position on the ring-shaped rail track and at a desired rate vector by maintaining equal tension on the one or more cables in both directions around the ring shaped rail track, and is moved about the axis of rotation by winding a first cable onto the cable winder spool from one direction and unwinding the first cable from the cable unwinder spool in the opposite direction.   
     
     
         20 . The method of  claim 16 , where the cable unwinder spool exactly follows the same torque amount required by the cable winder spool, which is also at a same rate by the cable winder spool but maintained equal and opposite in magnitude in order to keep tension in the cables, where the rate and the torque amount maintain a desired position on the ring shaped rail track and a desired shape of the heliostat mirror.