Techniques for adjusting solar array tracking
AssigneeSuncore Photovoltaics, Inc.
InventorJames Sherman
Life of this patent
Estimating the term…
Abstract
An automated method to monitor performance and adjust the programmed motion of a terrestrial solar cell array tracking the sun. The solar cell system includes two motor drives that adjust a position of the array along different respective axes with respect to the sun. A software algorithm predicts the position of the sun during the course of the day, and a kinematic model with adjustable encoding parameters controls the motor drives. Sampled data taken periodically may be used to update and modify the encoding parameters of the kinematic model in order to improve accuracy of the position of the array as it moves during the course of the day due to changes in mechanical or foundational positions supporting the array that may occur over the course of time.
Claims20
An automated method of causing a photovoltaic solar cell array of a terrestrial solar cell system to track the sun, the system comprising two motor drives each of which is operable to adjust a position of the array along a different respective axis with respect to the sun, the method comprising:
- (a) using a sun position predictor to predict a position of the sun in the sky at a time after sunrise based, at least in part, on the latitude, longitude and elevation of the array;
- (b) using a computer kinematic model to determine respective actuations for the motor drives corresponding to the solar cell array being substantially aligned with the sun during the course of the day, the kinematic model including encoding parameters;
- (c) using the sun position predictor and the kinematic model to position the array so that the array is aligned to follow a predetermined track corresponding to the predicted position of the sun during the course of the day;
- (d) periodically sampling the output of the array during the course of the day at sun position pi (where i=1 through n), and resetting the position of the array to a new sun position pi′ (where i=1 through n) that results in an increase in the output of the array at that position;
- (e) storing the sequence of new sun positions pi′ (where i=1 through n) corresponding to the track of the array during the course of a day in a memory;
- (f) adjusting the parameters of the kinematic model to form a list of test kinematic models over the range of sun positions;
- (g) evaluating each of the test kinematic models against a predetermined evaluation criteria as they simulate a progression through the range of sun positions during the course of the day;
- (h) selecting one of the test kinematic models that best meets the evaluation criteria;
- and
- (i) modifying the operational kinematic model of the array to conform to the parameters of the selected test kinematic model, so that subsequently the motion of the array at predetermined times during the course of the day tracks the set of reset positions with maximum output.
Dependencies are inferred from the claim text.