Adaptive solar powered system

• US 8,563,845 B2
• Filed: 04/06/2006
• Issued: 10/22/2013
• Est. Priority Date: 04/06/2006
• Status: Active Grant

• Current Assignee: Carmanah Technologies Corporation
• Original Assignee: Carmanah Technologies Corporation
• Inventors: Work, Jason N., Wyper, Neil D., Lightbody, Simon H.
• Primary Examiner(s): Mowla, Golam
• Application Number:
  US11/278,916
• Publication Number:
  US 20070235071A1
• Time in Patent Office: 2,756 Days
• Field of Search: 136/244, 136/291
• US Class Current: 136/244
• CPC Class Codes: H02J 7/35 with light sensitive cells
• CPC Class Codes: H02M 3/1588 comprising at least one synchronous rectifier element H02M3/1582, H02M3/1584 take precedence
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

An apparatus for powering a load from solar energy comprises a DC/DC converter, battery terminals coupled to an output of the DC/DC converter and coupleable to an energy storage device, and solar panel terminals coupled to an input of the DC/DC converter and coupleable to a solar panel. Logic is coupled to the converter to control its conversion rate. A detector is coupled to the converter and detects its power output. The logic is operable to adjust the conversion rate until the solar panel operates at the smaller of a maximum power point of the solar panel and a power point of the solar panel that results in a maximum desired power.

Claims

1. A method of determining a time to deliver an amount of energy to a load in a solar powered system having a solar panel, comprising differentiating artificial light from natural daylight by:

(a) providing an energy storage device for receiving energy from said solar panel;

(b) providing a processor; and

(c) providing a circuit for sensing photovoltaic output of said solar panel and for signaling said output to said processor to differentiates the artificial light from the natural daylight by;

(i) periodically measuring a value selected from the group comprising the short circuit current of said solar panel and the open circuit voltage of said solar panel;

(ii) measuring a rate of change of said value; and

(iii) determining the onset of day when both of the following conditions are met;

1. said value is above a predetermined threshold associated with daylight; and

2. said rate of change is larger than a rate of change for true dawn.

2. The method of claim 1 further comprising the step of adjusting said threshold.