Deployable solar array for small spacecraft

Patent metadata

Field	Value
Publication number	US-9919815-B2
Application number	US-201514921238-A
Country	US
Kind code	B2
Filing date	Oct 23, 2015
Priority date	Oct 24, 2014
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

The present disclosure provides, among other things, a deployable solar array comprising: an array of electromagnetic transducer devices such as photovoltaic devices; and a flexible, elongated, rectangular sheet for supporting the array of electromagnetic transducer devices composed of a composite laminate having a predetermined pattern of graphite fiber plies which impart a predefined tension in the planar surface of the sheet so that it curls into a planar sheet with a uniform radius of curvature along its major axis.

First claim

What is claimed is:

1. A deployable solar array comprising:
an array of solar cells, each of which has a backside surface mounted to a polyimide carrier, and
a flexible, elongated, rectangular sheet supporting the array of solar cells, wherein the sheet has a surface that faces the backside surfaces of all the solar cells in the array, the surface of the sheet having an area that is greater than a combined area of the backside surfaces of all the solar cells in the array, the sheet composed of a composite laminate to which the polyimide carrier is bonded, the composite laminate including graphite fiber plies that impart a tension in the surface of the sheet so that the sheet is operable to curl into a curvilinear sheet having a uniform radius of curvature along a major axis of the sheet,
wherein the sheet is operable to be circumferentially wound to form a spool configuration in a stowed configuration and is operable to form into a planar sheet having a uniform cross-sectional curvature as the sheet unwinds from the spool configuration upon deployment to a deployed configuration.

2. The deployable solar array of claim 1 wherein the sheet is present in regions extending from each solar cell in the array to one or more adjacent solar cells in the array.

3. The deployable solar array of claim 1 wherein the sheet has a width of less than 100 mm and a thickness of between 0.1 mm and 0.3 mm.

4. The deployable solar array of claim 1 wherein the graphite fiber plies give the sheet a strength of up to 0.28 g, a capability of handling stress when deployed at a vibration frequency of up to 0.9 Hz, and a stability of up to 1 milli-g under deployed flight loading.

5. A deployable solar array comprising:
an array of coverglass-interconnected (CICs) solar cells, each of which has a backside surface mounted directly on a polyimide carrier by a pressure sensitive adhesive; and
a flexible, elongated, rectangular sheet having a width of less than 100 mm and a thickness of between 0.1 mm and 0.3 mm for supporting the array of solar cells, wherein the sheet has a surface that faces the backside surfaces of all the solar cells in the array, the surface of the sheet having an area that is greater than a combined area of the backside surfaces of all the solar cells in the array, the sheet composed of a composite laminate to which the polyimide carrier is bonded, the composite laminate having a predetermined pattern of graphite fiber plies which impart a predefined tension in the surface of the sheet so that the sheet can curl into a curvilinear sheet having a uniform radius of curvature along a major axis of the sheet, wherein the pattern of graphite fiber plies includes intermediate modulus 7 (IM7) plies oriented at least 30° apart from each other, and
wherein the sheet is operable to be circumferentially wound to form a spool configuration in a stowed configuration and is operable to form into a planar sheet having a uniform cross-sectional curvature as the sheet unwinds from the spool configuration upon deployment to a deployed configuration.

6. A deployable solar array as defined in claim 5 , wherein the array of solar cells includes a first module having a first side dimension, and a second module having a second side dimension different from the first side dimension, each module including a plurality of discrete solar cells connected in a serial or parallel configuration.

7. A deployable solar array as defined in claim 5 , wherein the graphite fiber plies give the sheet a strength of up to 0.28 g, a capability of handling stress when deployed at a vibration frequency of up to 0.9 Hz, and a stability of up to 1 milli-g under deployed flight loading.

8. The deployable solar array of claim 5 wherein the sheet is present in regions extending from each solar cell in the array to one or more adjacent solar cells in the array.

9. A deployable solar array comprising:
an array of solar cells, each of which has a backside surface mounted directly on a polyimide carrier by a pressure sensitive adhesive, wherein the array of solar cells includes an array of coverglass-interconnected (CICs) solar cells; and
a flexible, elongated, rectangular sheet having a width of less than 100 mm and a thickness of between 0.1 mm and 0.3 mm for supporting the array of solar cells, wherein the sheet has a surface that faces the backside surfaces of all the solar cells in the array, the surface of the sheet having an area that is greater than a combined area of the backside surfaces of all the solar cells in the array, the sheet composed of a composite laminate to which the polyimide carrier is bonded, the composite laminate having a predetermined pattern of graphite fiber plies which impart a predefined tension in the surface of the sheet so that the sheet can curl into a curvilinear sheet having a uniform radius of curvature along a major axis of the sheet,
wherein the sheet is operable to be circumferentially wound to form a spool configuration in a stowed configuration and is operable to form into a planar sheet having a uniform cross-sectional curvature as the sheet unwinds from the spool configuration upon deployment to a deployed configuration, and
wherein the pattern of graphite fiber plies gives the sheet a strength of up to 0.28 g, a capability of handling stress when deployed at a vibration frequency of up to 0.9 Hz, and a stability of up to 1 milli-g under deployed flight loading.

10. The deployable solar array of claim 9 wherein the pattern of graphite fiber plies includes intermediate modulus 7 (IM7) plies.

11. A small spacecraft with deployable solar array for providing less than 50 watts of power comprising:
first and second deployable solar arrays, each of the deployable solar arrays including:
an array of solar cells, each of which has a backside surface mounted directly on a polyimide carrier by a pressure sensitive adhesive, wherein the array of solar cells comprises a string of solar cell assemblies connected in at least one of a serial or parallel electrical configuration; and
a flexible, elongated, rectangular sheet for supporting the array of solar cells, wherein the sheet has a surface that faces the backside surfaces of all the solar cells in the array, the surface of the sheet having an area that is greater than a combined area of the backside surfaces of all the solar cells in the array, the sheet composed of a composite laminate to which the polyimide carrier is bonded, the composite laminate having a predetermined pattern of graphite fiber plies which impart a predefined tension in the surface of the sheet so that the sheet can curl into a curvilinear sheet having a uniform radius of curvature along a major axis of the sheet, wherein the pattern of graphite fiber plies includes intermediate modulus 7 (IM7) plies oriented at least 30° apart from each other, and wherein the sheet is operable to be circumferentially wound to form a spool configuration in a stowed configuration and is operable to form into a planar sheet having a uniform cross-sectional curvature as the sheet unwinds from the spool configuration upon deployment to a deployed configuration;

a mandrel in the spacecraft configured for supporting the rectangular sheet of each deployable solar array in a stowed configuration in the spacecraft in which the sheets are coiled under compressive force; and
a deployment aperture on the spacecraft for enabling the automatic unwinding of the sheets from the mandrel during a deployment operation so that the sheet of the first deployable solar array is deployed in a first direction from the spacecraft and the sheet of the second deployable solar array is deployed in the same plane as the sheet of the first deploya

Assignees

• Solaero Tech Corp

Inventors

• Steele Kenneth Loyd
• Stern Theodore Garry

Classifications

• Y02E10/52

  PV systems with concentrators · CPC title

• H02S30/20 Primary

  Collapsible or foldable PV modules · CPC title

• B64G1/222

  for deploying structures between a stowed and deployed state · CPC title

• B64G1/443 Primary

  Photovoltaic cell arrays · CPC title

• H02S40/42

  Cooling means · CPC title