Patent US5648731A successfully refreshed from Google Patents.
US5648731A
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US
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Method of checking solar panel characteristics in an operating solar electrical system
Assignee: Northrop Grumman Systems Corp
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Filing: 1996-02-05
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Granted: 1997-07-15
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Expires: 2016-02-05
Abstract
Abstract In a solar electric supply system in which an electrical load is supplied with current produced by a solar array formed of multiple solar panels, each solar panel is individually selected and tested to ensure proper performance by varying the duty cycle of an associated variable transconductance device connected between such solar panel and the electrical load. The method determines the respective solar panel's open circuit voltage, its full-load current and obtains various output voltage and current values responsive to different duty cycles, whereby the maximum power point for the solar panel may be determined.
Inventors
- 👤 Darwin Kent Decker
- 👤 Charles B. Loftis, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 11:49
CPC Classifications
G; G05; G05F; G05F1/00; G05F1/66; G05F1/67; H; H01; H01M; H01M10/00; H01M10/42; H01M10/46; H01M10/465; H02; H02J; H02J4/00; H02J7/00; H02J7/34; H02J7/35; Y; Y02; Y02E; Y02E10/00; Y02E10/50; Y02E10/56; Y02E60/00; Y02E60/10; Y10; Y10S; Y10S136/00; Y10S136/291; Y10S136/293
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
276 words
The method of determining the voltage and current characteristics of a solar panel and variable transconductance device combinations from amongst a plurality of such combinations in and during operation of a solar powered power supply system that produces and supplies electrical power to a load via a bus, said load including a rechargable battery and said bus being clamped to a bus voltage, Vbus, each of such solar panel and variable transconductance device combinations being connected to deliver electrical power to said load, comprising the steps of: selecting one solar panel and variable transconductance device combination for test from amongst said plurality of such solar panel and variable transconductance device combinations; prescribing in sequence each of a plurality of duty cycles from a plurality of test duty cycle values and adjusting said variable transconductance device to each selected duty cycle in said sequence, and at least one of said plurality of duty cycles being equal to zero per cent and at least one other of said plurality of duty cycles being equal to one-hundred per cent; measuring electrical current generated by and the electrical voltage at the output of said solar panel in said solar panel and variable transconductance device under test at each said plurality of duty cycles to produce a series of values of voltage and current in respect of each respective duty cycle; and determining from said series of values each of the solar panel's open circuit voltage, Voc; the solar panels short circuit current, Isc, when clamped to a bus voltage, Vbus; the maximum power point voltage, Vmp; the maximum power point current, Imp; and the ratio of Vmp to Voc, Ratio.
Claim 2
Independent Claim
276 words
The method of determining the voltage and current characteristics of a solar panel and variable transconductance device combinations from amongst a plurality of such combinations in and during operation of a solar powered power supply system that produces and supplies electrical power to a load via a bus, said load including a rechargable battery and said bus being clamped to a bus voltage, Vbus, each of such solar panel and variable transconductance device combinations being connected to deliver electrical power to said load, comprising the steps of: selecting one solar panel and variable transconductance device combination for test from amongst said plurality of such solar panel and variable transconductance device combinations; prescribing in sequence each of a plurality of duty cycles from a plurality of test duty cycle values and adjusting said variable transconductance device to each selected duty cycle in said sequence, and at least one of said plurality of duty cycles being equal to zero per cent and at least one other of said plurality of duty cycles being equal to one-hundred per cent; measuring electrical current generated by and the electrical voltage at the output of said solar panel in said solar panel and variable transconductance device under test at each said plurality of duty cycles to produce a series of values of voltage and current in respect of each respective duty cycle; and determining from said series of values each of the solar panel's open circuit voltage, Voc; the solar panels short circuit current, Isc, when clamped to a bus voltage, Vbus; the maximum power point voltage, Vmp; the maximum power point current, Imp; and the ratio of Vmp to Voc, Ratio.
Claim 3
Dependent Claim
17 words
The method as defined in claim 1 further comprising the additional step of storing said determined values.
Claim 4
Dependent Claim
30 words
The method as defined in claim 1 further comprising the additional steps of defining a curve which fits essentially to the values of voltage produced as plotted against current produced.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-07-14 | 2001-01-13 | 2001-07-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-07-14 | 2005-01-13 | 2005-07-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-07-14 | 2009-01-13 | 2009-07-15 | $7700.00 | Window Closed / Lapsed |