Global solar tracking system

Abstract

A system may include determination of whether solar tracking of a first period of time is to be performed in a first region of sky or in a second region of sky, determination of a target tracker position in a first coordinate system if the solar tracking of the first period of time is to be performed in the first region of sky, and determination of the target tracker position in a second coordinate system if the solar tracking of the first period of time is to be performed in the second region of sky. In some aspects, determination of the target tracker position in the second coordinate system includes subtracting 360° from an azimuth angle in the first coordinate system if the azimuth angle in the first coordinate system is between +180° and +360°, wherein the azimuth angle in the second coordinate system is determined to be equal to the azimuth angle in the first coordinate system if the azimuth angle in the first coordinate system is between 0 and +180°.

1 . A method comprising:
 determining whether solar tracking during a first period of time is to be performed in a first region of sky or in a second region of sky;   determining a target tracker position in a first coordinate system if the solar tracking during the first period of time is to be performed in the first region of sky; and   determining the target tracker position in a second coordinate system if the solar tracking during the first period of time is to be performed in the second region of sky.   
     
     
         2 . A method according to  claim 1 , wherein the determined target tracker position comprises an azimuth angle, the method further comprising:
 controlling a solar tracker to move to the determined target tracker position during the first period of time.   
     
     
         3 . A method according to  claim 2 , wherein the first region of sky is primarily a northern portion of sky with respect to the solar tracker, and
 wherein the second region of sky is primarily a southern portion of sky with respect to the solar tracker.   
     
     
         4 . A method according to  claim 2 , further comprising:
 determining a second target tracker position in the first coordinate system if the solar tracking during the first period of time is to be performed in the first region of sky;   determining the second target tracker position in the second coordinate system if the solar tracking during the first period of time is to be performed in the second region of sky; and   controlling the solar tracker to move to the determined second target tracker position during the first period of time.   
     
     
         5 . A method according to  claim 4 , further comprising:
 determining whether solar tracking during a second period of time is to be performed in the first region of sky or in the second region of sky;   determining a third target tracker position in the first coordinate system if the solar tracking during the second period of time is to be performed in the first region of sky;   determining the third target tracker position in the second coordinate system if the solar tracking during the second period of time is to be performed in the second region of sky; and   controlling the solar tracker to move to the determined third target tracker position during the second period of time.   
     
     
         6 . A method according to  claim 1 , wherein determining the target tracker position in the second coordinate system comprises:
 determining an azimuth angle in the first coordinate system; and   determining an azimuth angle in the second coordinate system based on the azimuth angle in the first coordinate system.   
     
     
         7 . A method according to  claim 6 , wherein the first coordinate system comprises azimuth angles between 0° and +360°, and wherein the second coordinate system comprises azimuth angles between −180° and +180°. 
     
     
         8 . A method according to  claim 7 , wherein determining the target tracker position in the second coordinate system comprises:
 subtracting 360° from the azimuth angle in the first coordinate system if the azimuth angle in the first coordinate system is between +180° and +360°,   wherein the azimuth angle in the second coordinate system is determined to be equal to the azimuth angle in the first coordinate system if the azimuth angle in the first coordinate system is between 0° and +180°.   
     
     
         9 . A method according to  claim 1 , wherein determining whether solar tracking during the first period of time is to be performed in the first region of sky or in the second region of sky comprises:
 determining an azimuth angle of the sun corresponding to noon of the first period of time;   determining that solar tracking during the first period of time is to be performed in the first region of sky if the azimuth angle of the sun corresponding to noon of the first day is within the first region of sky; and   determining that solar tracking during the first period of time is to be performed in the second region of sky if the azimuth angle of the sun corresponding to noon of the first period of time is within the second region of sky.   
     
     
         10 . A method according to  claim 1 , wherein the determination of whether solar tracking during the first period of time is to be performed in the first region of sky or in the second region of sky is performed before dawn and after 12:01 a.m. of the first period of time. 
     
     
         11 . A method according to  claim 1 , wherein determining whether solar tracking during the first period of time is to be performed in the first region of sky or in the second region of sky comprises:
 determining a date on which a solar position changes between the first region of sky and the second region of sky.   
     
     
         12 . A system comprising:
 a solar tracker; and   a control unit coupled to the solar tracker and to:
 determine whether solar tracking during a first period of time is to be performed in a first region of sky or in a second region of sky; 
 determine a target tracker position in a first coordinate system if the solar tracking during the first period of time is to be performed in the first region of sky; and 
 determine the target tracker position in a second coordinate system if the solar tracking during the first period of time is to be performed in the second region of sky. 
   
     
     
         13 . A system according to  claim 12 , wherein the determined target tracker position comprises an azimuth angle, the control unit further to:
 control the solar tracker to move to the determined target tracker position during the first period of time.   
     
     
         14 . A system according to  claim 13 , wherein the first region of sky is primarily a northern portion of sky with respect to the solar tracker, and
 wherein the second region of sky is primarily a southern portion of sky with respect to the solar tracker.   
     
     
         15 . A system according to  claim 13 , the control unit further to:
 determine a second target tracker position in the first coordinate system if the solar tracking of the first period of time is to be performed in the first region of sky;   determine the second target tracker position in the second coordinate system if the solar tracking of the first period of time is to be performed in the second region of sky; and   control the solar tracker to move to the determined second target tracker position during the first period of time.   
     
     
         16 . A system according to  claim 15 , the control unit further to:
 determine whether solar tracking of a second period of time is to be performed in the first region of sky or in the second region of sky;   determine a third target tracker position in the first coordinate system if the solar tracking of the second period of time is to be performed in the first region of sky;   determine the third target tracker position in the second coordinate system if the solar tracking of the second period of time is to be performed in the second region of sky; and   control the solar tracker to move to the determined third target tracker position during the second period of time.   
     
     
         17 . A system according to  claim 12 , wherein determining the target tracker position in the second coordinate system comprises:
 determining an azimuth angle in the first coordinate system; and   determining an azimuth angle in the second coordinate system based on the azimuth angle in the first coordinate system.   
     
     
         18 . A system according to  claim 17 , wherein the first coordinate system comprises azimuth angles between 0° and +360°, and
 wherein the second coordinate system comprises azimuth angles between −180° and +180°.   
     
     
         19 . A system according to  claim 18 , wherein determining the target tracker position in the second coordinate system comprises:
 subtracting  3600  from the azimuth angle in the first coordinate system if the azimuth angle in the first coordinate system is between +180°and +360°,   wherein the azimuth angle in the second coordinate system is determined to be equal to the azimuth angle in the first coordinate system if the azimuth angle in the first coordinate system is between 0° and +180°.   
     
     
         20 . A system according to  claim 12 , wherein the determination of whether solar tracking during the first period of time is to be performed in the first region of sky or in the second region of sky comprises:
 determining an azimuth angle of the sun corresponding to noon of the first period of time;   determining that solar tracking during the first period of time is to be performed in the first region of sky if the azimuth angle of the sun corresponding to noon of the first period of time is within the first region of sky; and   determining that solar tracking during the first period of time is to be performed in the second region of sky if the azimuth angle of the sun corresponding to noon of the first period of time is within the second region of sky.   
     
     
         21 . A system according to  claim 12 , wherein the determination of whether solar tracking during the first period of time is to be performed in the first region of sky or in the second region of sky is performed before dawn and after 12:01 a.m. of the first period of time. 
     
     
         22 . A method according to  claim 12 , wherein the determination of whether solar tracking during the first period of time is to be performed in the first region of sky or in the second region of sky comprises:
 determining a date on which a solar position changes between the first region of sky and the second region of sky.