JP2019050351A - Solar cell array having detoured sola cell - Google Patents

Abstract

To provide means for dealing with problems of operation of a solar cell array, or means for suppressing output voltage drop.SOLUTION: A solar cell array consists of one or more than one solar cells 14 attached to a board. The board includes one or more than one electrical connections with the solar cells. The board also includes one or more than one detour switches 54b for detouring one or more than one electrical connections with one or more than one solar cells. When closed, the switch connects the front contact points and the back contact points of the one or more than one solar cells, so that the current detours the one or more than one solar cells. A string length switch 54a for adding one or more than one solar cells to the solar cell string or removing therefrom is also provided, and the length of string is changed for changing the voltage generated by the string.SELECTED DRAWING: Figure 15

Description

  The present disclosure relates generally to solar cell panels, and more particularly to solar cell arrays having diverted solar cells.

  A typical space flightable solar cell panel assembly involves constructing a solar cell array consisting of a long string of solar cells connected in series. These strings can vary in length, i.e. the number of solar cells, and can be very long.

  Conventional solar cell arrays are built with a fixed number of solar cells to generate the required output voltage. For example, a string of 50 solar cells connected in series produces an output voltage of 100V. Failure of one or more of the solar cells in the string can significantly compromise the power provided by all 50 solar cells.

  This brings about a broad effort in the testing, verification and qualification of materials and processes to guarantee the maximum life and success of the solar cell array. However, such efforts increase costs and reduce innovation. Furthermore, the risk of some missions is too high and is completely avoided.

  Therefore, what is needed is a means to address the failure of operation of the solar cell array or that the expected output voltage is not supplied during its lifetime.

  In order to overcome the limitations of the prior art and overcome other limitations that will become apparent upon reading and understanding the present specification, the present disclosure includes one or more solar cells attached to the substrate, the substrate comprising: Solar, comprising one or more electrical connections to the solar cell, wherein the substrate comprises one or more switches for diverting one or more of the electrical connections to one or more of the solar cells Cell arrays, methods and devices are described.

  When at least one of the solar cells having one or more clipped corners is attached to the substrate, the area of the substrate remains exposed and the area of the substrate that remains exposed is at least one of the switches. Contains one. At least one of the solar cells is attached to the substrate such that the corner area defined by the trimmed corners of at least one of the solar cells is aligned, thereby exposing the area of the substrate . At least one of the switches is located within a corner area defined by the trimmed corner adjacent to at least one of the solar cells.

  The solar cell, one or more bypass diodes, and the switch are electrically connected in parallel. Furthermore, the switch is controlled by one or more control signals.

  The switch diverts current away from one or more of the solar cells. In particular, when the switch is closed, it connects one or more front and back contacts of the solar cell, and the current bypasses one or more of the solar cells.

  There is also a switch to add or remove one or more of the solar cells from the strings of solar cells, the length of the strings being changed to change the voltage generated by the strings Ru.

  Reference is now made to the drawings, wherein like reference numerals represent corresponding parts throughout the drawings.

Figure 1 shows the conventional structure of a solar cell panel. Figure 1 shows the conventional structure of a solar cell panel. A and B show the improved structure of the solar cell panel according to one example. A and B show alternative structures of solar cell panels according to one example. FIG. 3C shows the front of an exemplary solar cell that may be used with the improved solar cell panels of FIGS. Fig. 6 shows the back of the exemplary solar cell of Fig. 5; FIG. 7 illustrates cells arranged in a two-dimensional (2D) grid of an array, according to one example. Fig. 6 shows an example of an array in which one or more bypass diodes are added to the exposed area of the substrate in the corner area. Figure 7 illustrates an example where a bypass diode is attached to the back of the cell and an interconnect or contact for the bypass diode extends in the corner area between the front and back contacts. FIG. 10 shows a front view of the example of FIG. 9 with the interconnectors or contacts for the diverting diodes extending in the corner area between the front and back contacts. The cell of FIGS. 9 and 10 arranged in an array of 2D grids and attached to a substrate, wherein a bypass diode is attached to the back of the cell and a contact for the bypass diode extends into the corner area of the cell 10 show the cells of FIG. 9 and FIG. Fig. 6 shows an upward / downward series connection between cells of an array according to one embodiment. Fig. 6 illustrates a left / right series connection between cells of an array according to one embodiment. Fig. 3 shows a schematic diagram of a string consisting of two solar cells with a plurality of switches and connection paths shown. The bypassing of the solar cell shows how to include a single bypass switch connecting the front and back contacts of the solar cell. Shown is a set of three solar cells in a vertical row. 1 shows a single integrated device combining switch function with a bypass diode. The combined switch is shown adjacent to the bypass diode. A method of manufacturing a solar cell, a solar cell panel and / or a satellite according to one example is described. Fig. 6 shows the resulting satellite having a solar cell panel consisting of solar cells according to one example. FIG. 5 is a diagram of a solar cell panel in the form of a functional block diagram, according to one example. A to H show experimental results where a solar cell array using a flex circuit board was built to show the reconstruction of the string length of the array based on the corner conductor design.

  In the following description, reference is made to the accompanying drawings that form a part of the present application, and these attached drawings are illustrated for the purpose of illustrating specific examples in which the present disclosure may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present disclosure.

  A new approach to the design of solar cell arrays, for example for use in space power applications, is based on the electrical connections between solar cells in the array.

  These new approaches re-arrange the components of the solar cells and the array of solar cells in the array. Instead of connecting the solar cells into long linear strings and then assembling them on the substrate, the solar cells are individually attached to the substrate so that the corner areas of adjacent cells are aligned on the substrate, Expose a certain area. Electrical connections between the cells are made by corner conductors formed on or in the substrate and in these corner areas. As a result, this approach presents a solar cell array design based on individual cells.

  Thus, a single laydown process and layout can be used to fabricate a solar cell array. The flow of current between the solar cells will be assisted by conductors embedded in the substrate. These electrical connections define the specific characteristics of the solar cell array, such as its dimensions, the stayout area, and the termination of the circuit. This approach simplifies manufacturing, enables automation, reduces costs, and reduces delivery times.

  FIGS. 1 and 2 show a conventional structure of a solar cell panel 10, including a substrate 12, a plurality of solar cells 14 arranged in an array, and an electrical connector 16 between the solar cells 14. FIG. A half size solar cell 14 is shown in FIG. 1 and a full size solar cell 14 is shown in FIG. The space solar cell 14 is obtained from a round germanium (Ge) substrate starting material and is later processed into a semi-rectangular shape to enhance the high density packing on the solar cell panel 10. The wafer is often diced into one or two solar cells 14, which are described herein as half or full size solar cells 14. Electrical connectors 16 that provide electrical connection between the solar cells 14 are made along the long parallel edges between the solar cells 14. Since the strings that the solar cells 14 can connect to are constructed to have any number of solar cell 14 lengths, these series connections (cell to cell) are not attached to the substrate Complete with. The completed string of solar cells 14 is then applied to the substrate 12 and attached.

  In FIG. 2, wires 18 are attached to the ends of the strings of solar cells 14, which may be used to electrically connect the strings to other strings, or to terminate the wires into circuits to form solar cells. This is to break the current of the 14 arrays here. The connections between the strings and the connections of the circuit terminations are usually made on the substrate 12 and are usually made using the wiring 18. However, some solar cell panels 10 use printed circuit board (PCB) type materials embedded with conductors.

  Adjacent strings of connected solar cells 14 can extend parallel or anti-parallel. In addition, the strings made of connected solar cells 14 may or may not be aligned. There are many competing influences on the layout of the solar cell 14, so that there are parallel or anti-parallel, aligned or unaligned areas of the solar cell 14 Do.

  FIGS. 3A and 3B show an improved apparatus and structure of a solar cell panel 10a according to one embodiment, and FIG. 3B is an enlarged detail view within the dashed circle of FIG. 3A. In Figures 5 to 13 the various components of the solar cell panel 10a are shown and described in more detail.

  The solar cell panel 10a includes a substrate 12 for a solar cell 14 having one or more corner conductors 20 thereon. In one embodiment, substrate 12 is a multi-layer substrate 12 consisting of one or more Kapton® (polyimide) layers separating one or more patterned metal layers. The substrate 12 may be mounted to a large rigid substrate 10a similar to a conventional assembly. Alternatively, the substrate 12 can be mounted to a lighter or thinner frame or panel 10a for mounting or deployment.

  A plurality of solar cells 14 are attached to the substrate 12 in a two dimensional (2-D) grid of the array 22. In this embodiment, the array 22 is comprised of 96 solar cells 14 arranged in 4 rows × 24 rows, although in different embodiments any number of solar cells 14 may be used ,It recognized.

  The solar cell 14 has a trimmed corner 24 that defines a corner area 26, as indicated by the dashed circle. A plurality of solar cells 14 are attached to the substrate 12 and corner areas 26 of adjacent ones of the solar cells 14 are aligned, thereby exposing the area 28 of the substrate 12. The exposed area 28 of the substrate 12 includes one or more corner conductors 20, and between the solar cells 14 and the corner conductors 20 in a corner area 26 created by the trimmed corner portions 24 of the solar cells 14. One or more electrical connections are made.

  In this embodiment, the corner conductor 20 is attached to the substrate 12, printed on the substrate 12, embedded in the substrate 12, and / or embedded in the substrate 12 before and / or after the solar cell 14 is attached to the substrate 12. The conductive paths deposited thereon facilitate the connection between adjacent solar cells 14. The connection between the solar cell 14 and the corner conductor 20 is made after the solar cell 14 is attached to the substrate 12.

  In one embodiment, four adjacent solar cells 14 are aligned on substrate 12, and a total of four clipped corner portions 24, one from each solar cell 14, are gathered together at corner region 26. There is. The solar cells 14 are then individually attached to the substrate 12 and mounted on the corner conductors 20 to form an electrical connection between the solar cells 14 and the corner conductors 20.

  The solar cell 14 may be attached to the substrate 12 as a CIC (cell, interconnect, cover glass) unit. Instead, assemble the uncoated solar cells 14 on the substrate 12 and then attach the interconnects to the solar cells 14 followed by the cover glass for single cell solar cells 14, the cover glass for multi cell solar cells 14, multi cell Polymer cover sheet, or a spray-type encapsulant. This assembly protects the solar cell 14 from damage that would limit performance.

  4A and 4B show an alternative structure of the solar cell panel 10a according to one example, and FIG. 4B is a detail enlargement in the dashed circle of FIG. 4A. In this embodiment, only a few corner conductors 20 are printed on or integrated into the substrate 12. Instead, most of the corner conductors 20 are contained within a power routing module (PRM) 30 attached to the substrate 12.

  FIG. 5 shows the front of an exemplary solar cell 14 that may be used with the improved solar cell panel 10a of FIGS. 3A-B and 4A-B. The solar cell 14 is a CIC unit, and is a half-sized solar cell 14. (A full size solar cell 14 could also be used.)

  As shown by the dashed circle, the solar cell 14 is manufactured to have at least one clipped corner 24 that defines a corner region 26, and in the corner region 26 made by the clipped corner 24. Includes at least one contact 32, 34 in electrical connection with the solar cell 14. In the embodiment shown in FIG. 5, the solar cell 14 has two clipped corners 24, each having a front contact 32 on the front of the solar cell 14 and a back contact 34 on the back of the solar cell 14. And the contacts 32 and 34 extend into the corner area 26. (A full size solar cell 14 will have four clipped corners 24, each of which will have a front contact 32 and a back contact 34.)

  The trimmed corners 24 increase the utilization of round wafer starting material for the solar cell 14. In the conventional panel 10, these clipped corners 24 will provide unused space above the panel 10 after the solar cell 14 is attached to the substrate 12. However, the unused space is used in the new approach described in the present disclosure. Specifically, a metal foil interconnect comprising corner conductor 20, front contact 32 and back contact 34 is moved to corner region 26. In contrast, existing CICs have interconnects attached to the front of the solar cell 14 and are connected to the back (where connections occur) during string fabrication.

  The current generated by the solar cell 14 is collected at the front of the solar cell 14 by the narrow metal fingers 38 and the wider grid of metal bus bars 40 connected to either front contact 32. A balance exists while adding metal to grid 36, reducing the light incident on solar cell 14 and its output power, and reducing the resistance of having more metal. The bus bar 40 is a low resistance conductor that carries high current, and also provides redundancy if the front contact 32 is disconnected. Optimization generally requires short bus bars 40 passing directly between the front contacts 32. By having the front contacts 32 at the cut corners 24, the bus bars 40 move away from the periphery of the solar cell 14. This is accomplished while simultaneously minimizing bus bar 40 length and light ambiguity. In addition, this also makes the fingers 38 shorter. This reduces the parasitic resistance of the grid 36, as the fingers 38 are shorter and the total current carried is less. This gives rise to a design preference to move the front contacts 32 and the connecting busbars 40 in order to provide shorter, narrow fingers 38.

  FIG. 6 shows the back of the exemplary solar cell 14 of FIG. The back of the solar cell 14 has a metal back layer 42 that is bonded to both of the back contacts 34.

  FIG. 7 shows solar cells 14 arranged in a 2D grid of array 22 according to one embodiment. Array 22 includes a plurality of solar cells 14 attached to substrate 12 such that corner regions 26 of adjacent ones of solar cells 14 are aligned, thereby exposing regions 28 of substrate 12. The electrical connections (not shown) between the solar cells 14 are the front contacts 32 and the back contacts 34 of the solar cells 14 and the corner conductors 20 formed on or in the exposed areas 28 of the substrate 12 (see FIG. (Not shown) is done in the exposed area 28 of the substrate 12.

  During assembly, the solar cells 14 are individually attached to the substrate 12. This assembly can be done directly on the support surface or substrate 12 which may be either rigid or flexible. Alternatively, the solar cells 14 could be assembled in a 2D grid of the array 22 on a temporary support surface and then transferred to the final support surface, ie the substrate 12.

  FIG. 8 illustrates one embodiment of the array 22 with one or more bypass diodes 44 added for use in one or more electrical connections in the exposed area 28 in the corner area 26 of the substrate 12 . The bypass diode 44 protects the solar cell 14 when the solar cell 14 can not generate current, but it is partly because the solar cell 14 can not generate current. However, in that case, the solar cell 14 is reverse biased. In one embodiment, the bypass diode 44 is attached to the substrate 12 in the corner area 26 independently of the solar cell 14.

  In FIG. 9, a bypass diode 44 is attached to the back of the solar cell 14, and an interconnector or contact 46 for the bypass diode 44 is connected to the back layer 42, and a corner between the front contact 32 and the back contact 34. One embodiment is shown extending into region 26.

  FIG. 10 is a front view of the embodiment of FIG. 9 in which an interconnector or contact 46 for bypass diode 44 (not shown) extends into corner area 26 between front contact 32 and back contact 34. Indicates

  FIG. 11 shows the solar cells 14 of FIGS. 9 and 10 arranged in a 2D grid of the array 22 and attached to the substrate 12, but here the back-to-back diodes 44 (not shown) The contacts 46 for the diverting diode 44 extend into the corner area 26 of the solar cell 14.

  One advantage of this approach is that the layout shown in FIGS. 7, 8 and 11 is a generalized layout. In particular, these layouts can be repeated over any dimensions desired by the customer of panel 10a. This greatly simplifies the process of assembly, rework, testing and inspection.

  The arrangement of the solar cell 14 and the bypass diode 44 is general. The series connection of the solar cells 14 and the electrical connection to the string terminations are important customizations for the end customer and are made independent of the layout. The front contact 32 and the back contact 34 in the corner area 26 of the solar cell 14 must be connected. This can be done in many combinations to route the current through the desired path.

  A connection is made between the solar cell 14 and the corner conductor 20. A front contact 32 and a back contact 34 of the solar cell 14 are present in each corner area 26 for attachment to the corner conductor 20. The interconnects for the front contacts 32 and the back contacts 34 of each solar cell 14 are welded, soldered or otherwise attached to the corner conductor 20 to provide conductive paths 20, 32, 34 for routing current outside the solar cell 14. Bonded in the manner of

  The corner conductor 20 can be used to make any customization in the electrical connection. Adjacent solar cells 14 can be electrically connected to conduct current in the vertical or horizontal direction as desired by the particular design. Also, if desired, current flow can be routed around stay-out zones. The length and width of the solar cell array 22 can be set as desired. Also, the width of the array 22 may vary depending on its length.

  In one embodiment, the electrical connection is a series connection that determines the flow of current through the plurality of solar cells 14. This can be achieved by the connection scheme shown in FIGS. 12 and 13, but FIG. 12 shows an upward / downward series connection 48 between the solar cells 14 of the array 22 and FIG. The left / right series connection 50 between the solar cells 14 of FIG. In both FIG. 12 and FIG. 13, these series connections 48, 50 are electrical connections between the front contact 32 and back contact 34 of the solar cell 14 and the bypass diode 44, and these series connections are This is done using corner conductors 20 formed on or in the exposed area 28 of the substrate 12. These series connections 48, 50, as indicated by the arrows 52, determine the flow of current (power) through the solar cell 14.

  The corner conductors 20 between the solar cells 14 can take many forms. The corner conductor 20 could be completed using a wire having electrical connections made at both ends in a manner that can be soldering, welding, conductive adhesives, or other treatments. In addition to wires, metal foil connectors similar to interconnects could also be applied. Metal conductor paths or traces (not shown) can also be incorporated into the substrate 12.

  In essence, this new approach allows the solar cells 14 to be individually substrate 12 such that corner regions 26 of two, three or four adjacent solar cells 14 are aligned on the substrate 12. It is attached to The solar cells 14 may be positioned such that the trimmed corners 24 are aligned and the corner areas 26 are adjacent, thereby exposing the area 28 of the substrate 12. The electrical connections between the solar cells 14 are in these corner areas 26 on the front contacts 32 and back contacts 32 of the solar cells 14, the bypass diodes 44 and the corners on or in the exposed areas 28 of the substrate 12. Although made between conductors 20, these conductive paths are used to create a string of solar cells 14 in series connection 48, 50 containing circuitry.

Solar cell array with diverted solar cells A space based solar cell array 22 can not generally be serviced. Thus, failure is a major concern and not only avoids some missions but leads to an extensive quality program.

  The solar cell array 22 joins together the many solar cells 14 to generate power to generate an output voltage. In one example, a string of 50 solar cells 14 in series produces an output voltage of 100V. The failure of one or more solar cell arrays 14 in a string can significantly compromise the power provided by all 50 solar cells 14.

  The present disclosure provides a mechanism for bypassing the solar cell 14 and thus does not compromise the string. Also, the length of the string can be changed by adding or removing solar cells 14. All in all, these capabilities allow the solar cell array 22 to continue to generate power upon failure of the solar cell 14.

  Solar cells 14 are generally connected in series in a string. A single triple junction solar cell 14 in a string produces about 2V. The photocurrent exits from the back side (i.e., p side) of the solar cell 14, but the back side of the first solar cell 14 is connected in series to the front side (i.e., n side) of the second solar cell 14. . The photocurrent exits from the back of the second solar cell 14 again. The current is constant through the solar cells 14 connected in series, but gets 2V from each additional solar cell 14.

  An important design specification is the voltage required to operate the system. This is often 100 V but fluctuates significantly.

  Damage to the solar cell 14, the bypass diode 44, or their electrical connections can significantly reduce the power provided by the string. Due to the nature of series connection of strings, failure of one or more solar cells 14 can reduce power by more than 50%.

  The present disclosure describes diverting the solar cell 14 and its bypass diode 44 away from the string such that the solar cell 14 is consequently removed from the string, causing a voltage drop in the string. The string should also change by adding solar cells 14 to the string after removing the solar cells 14 from the string to maintain output voltage and peak power generation. Typically, the length of the string will be maintained or increased to provide an output of 100 V without degradation due to the diverted solar cell 14.

  FIG. 14 shows a schematic diagram of a string of two solar cells 14 attached to a substrate 12, which includes one or more electrical connections to the solar cells 14, each solar cell 14 bypassing A diode 44 is provided. Each solar cell 14 also has a set of one or more string length switches 54a for changing the length of the strings and a bypass switch 54b for diverting the solar cells 14, whereby the solar cells Change the electrical connection to 14.

  Solar cell 14 includes a current source, a shunt resistor, and a diode, which is a general circuit representation. This simplifies the consideration of how the solar cell array 22 may change. Shadowing or destruction of the solar cell 14 will reduce the current source. Damage to the solar cell 14 can reduce shunt resistance.

  The interconnects 56 are also shown, each of these interconnects 56 comprising two flange elements with parallel planes joined by a web element, thus resembling the letter H whose side is inclined looks like. The interconnect 56 is a piece of metal foil used to connect the device (solar cell 14, bypass diode 44, switch 54) to the conductor 20.

  The connections 58 between the interconnects 56, the devices 14, 44, 54 and the conductors 20 are shown as small squares. These connections 58 may be soldered or welded connections 58.

  The conductor 20 could possibly be a wire, but the complex network of electrical connections between the solar cells 14 is forbidden and would require extensive effort and occupation of the panel 10a area. However, the use of corner conductors 20 in the solar cell array 22 enables this approach. This layout of the solar cell 14 places all the required conductors 20 in close proximity (in the corner area 26) and also allows the devices 14, 44, 54 to be present in the corner area 26.

  Next, the solar cell 14 can be assembled on a substrate 12, such as a flex circuit substrate 12, which is readily available in a space licensed construction method. The flex circuit board 12 has metal traces that can form the wiring pattern of the electrical connections shown in the figure. These electrical connections would be virtually impossible with conventional solar cell arrays, but would be simplified in the corner connection layout of the present disclosure.

  FIG. 14 shows a string having a length of two solar cells 14. This is not very useful in practice, but serves to demonstrate the functionality of the present disclosure. The polarity is such that, when illuminated, photocurrent flows upward in each solar cell 14 as indicated by the upward pointing current source. The resulting voltage will also be higher at the top (VX + connection) rather than at the bottom of the figure. The two right string length switches 54a can control the output. The illustrated outputs include the positive and negative polarity of the two outputs V1 and V2. As the starting point of the solar cell array 22, V1- is fixed. After the bottom solar cell 14, a set of string length switches 54a can control the output to terminate at V1 +. In this case, the upper solar cell 14 will be connected to V2-. And, the output of the top solar cell 14 will then be switched to V2 + by a pair of string length switches 54a. In this configuration, there will be two outputs with one solar cell 14 power at each output.

  The string length switch 54a could also be set so that current follows the upper solar cell 14 despite passing through the two string length switches 54a after the lower solar cell 14. The current then passes through the upper solar cell 14 where the voltage rises. The output is then directed to V1 +. V1 + has the same current as before, but now the voltage is doubled. Circuit lines V2- and V2 + can be connected together to avoid any floating unconnected conductors.

  If the solar cell 14 or the bypass diode 44 is not operating properly, the left bypass switch 54b can be closed to divert the solar cell 14 and the bypass diode 44 out of the string. When closed, the switch 54b will form a low resistance path that bypasses the solar cell 14, resulting in the solar cell 14 having approximately zero volts and little or no current flow across it.

  This operation will remove the solar cells 14 from the string, resulting in a voltage drop in the string. In order to maintain the output voltage and peak power generation, the string must also change, which requires another set of switches 54a to add functional solar cells 14 to the string. Typically, the string length will be maintained or increased so that the string provides a 100 V output without degradation due to the solar cell 14 which is then bypassed.

  Typical building blocks for the space based solar cell array 22 are the solar cell 14 and the bypass diode 44. In the present disclosure, the building blocks are now the solar cell 14, the bypass diode 44, the string length switch 54a, and the bypass switch 54b. This highly functional building block, in combination with the corner connection layout, can be used to build a solar cell array 22 with surprising functionality.

  The resulting configuration will allow bypassing of any single solar cell 14 or group of solar cells 14. Current will then be routed around the solar cell 14 through the bypass switch 54b. The length of the string could then be extended as needed to reach the required output voltage. FIG. 14 illustrates switch control and bypass control at the level of the individual solar cells 14. It is easy to modify the connection so that groups of solar cells 14 can be diverted as s groups. This is similar to switching the solar cells 14 as a group.

  The bypass diode 44 plays a role similar to that of the bypass switch 54b. The bypass switch 54b is controlled through an external system that senses operation, determines the switch configuration, and transmits information to the switch. These operations are internal to the bypass diode 44 and are automatic. If the forward bias applied to the bypass diode 44 is greater than 0.7 V, current will automatically flow through the low resistance bypass diode 44. With an appropriate sensing and control system, the bypass switch 54b could eliminate the need for the bypass diode 44.

  FIG. 15 illustrates how solar cell 14 is bypassed by a single bypass switch 54b connecting front contact 32 and back contact 34 of solar cell 14 in a corner connection layout. Additionally, a set of string length switches 54a is used to adjust the string length.

  The corner connection layout is used in this example for a solar cell array 22 consisting of four solar cells 14 each having at least one clipped corner 24. The solar cell 14 comprises a substrate 12, ie, a flex circuit substrate 12, such that corner regions 26 of adjacent ones of the solar cell cells 14 resulting from the pruned corner 24 are aligned, thereby exposing the area 28 of the substrate 12. Attached to The front contacts 32 and the back contacts 34 of the solar cell 14 extend within the exposed area 28 of the substrate 12. The exposed area 28 of the substrate 12 also provides one or more electrical connections between the front contact 32 and the back contact 34 of the solar cell 14, as well as the bypass diode 44, the string length switch 54a and the bypass switch 54. Also includes the corner conductor 20 of FIG.

  The exposed area 28 of the substrate 12 also includes one or more bypass switches 54b for bypassing the electrical connection to one or more of the solar cells 14, and when the switch 54b is closed, the solar cells 14's One or more of the front contact 32 and the back contact 34 of the solar cell 14 are coupled to bypass the electrical connection to one or more of them. The corner connection layout simplifies the use of the bypass switch 54b since the front contact 32 and the back contact 34 are physically adjacent to one another. Further, the front contacts 32 and the back contacts 34 can access the traces on the flex circuit board 12.

  The corner connection layout also provides another important capability for solar cell 14 bypass. Specifically, flex circuit board 12 may include traces under solar cells 14 that are electrically isolated from solar cells 14.

  Further, the exposed area 28 of the substrate 12 is to modify the strings of the solar cells 14 by adding one or more of the solar cells 14 to and / or removing the electrical connections of the string. It also includes one or more sets of switches 54a. The string is modified to change the voltage generated by the string.

  FIG. 16 shows a set of three solar cells in a vertical row. The bus bars 40 are low resistance metal conductors on the surface of the solar cell 14 that carry current from the individual narrow metal fingers 38 of the grid 36 (not shown) to the front contacts 32 of the solar cell 14. Each end of the bus bar 40 is connected to a front contact 32 that can be connected to a trace on the flex sheet substrate 12. The back contact 34 is connected to the back of the solar cell 14.

  The dashed lines are the traces 60, 62 in or on the flexsheet substrate 12 below the solar cell 14 electrically isolated from the solar cell 14. These traces 60, 62 provide parallel current paths for the front 32 and back 34 contacts of the solar cell 14 between each corner. These traces 60, 62 also provide a current path for bypassing the solar cell 14 and allow current to flow under the solar cell 14 when the solar cell 14 is bypassed. This is similar to the discussion of stayout zones found in some of the cross-referenced applications above.

  The corner area 26 may also include bypass diodes 44 and corner conductors 20 that support the series connection of these solar cells 14. Current will flow from top to bottom through these three solar cells 14.

  The bypass switch 54 b is also shown in the corner area 26. Although only a single bypass switch 54b is required for each corner area 26, the second bypass switch 54b in corner area 26 provides additional protection from failure.

  Referring again to FIG. 15, switch 54 is illustrated as a single pole single throw (SPST) switch 54. Such a switch 54 may be based on a semiconductor such as, for example, a silicon (Si) MOSFET (metal oxide semiconductor field effect transistor) or a gallium nitride (GaN) or silicon carbide (SiC) FET (field effect transistor). Can be obtained from multiple vendors for space applications.

  However, to simplify assembly, the functions of switch 54 and bypass diode 44 could be combined into a single integrated device. The semiconductor or MEMS (micro-electro-mechanical system) switch 54 could be fully integrated with the bypass diode 44 on a common semiconductor wafer or via various integration techniques.

  A single integrated device 64 combining the function of the switch 54 and the bypass diode 44 is shown in FIG. The thick dark line represents the conductive path 66 through the integrated device 64 in the corner area 26. The short parallel lines labeled AF in integrated device 64 represent switch 54, which can change the resistance in that region from a very low value to a very high value. The diode symbol between switch E and C / D 54 represents the bypass diode 44. The operation of these switches 54 controls the operation of the series pair circuit termination and the bypass operation of the solar cell 14 performed by the integrated device 64.

  Device 64 of FIG. 17 has one more switch 54 than the layout of FIGS. This extra switch 54 allows termination of any solar cell 14 connected to the device 64. Another way to understand this is that each solar cell 14 in the configuration can be terminated at any corner.

  Not shown is the control of the integrated device 64 and its switch 54. This could be achieved with different communication strategies. A common method would be to continuously transmit information including the addresses for identifying the integrated device 64 and the switches 54 (A-F), and transmit the open / close status of each switch 54. This continuous communication is generally performed by a clock signal and an information signal with a power and ground line. These communication lines can be integrated into the flex circuit board 12. Because they do not carry much power or current, the size of the conductors can be much smaller than the other traces and can be easily integrated into the flex circuit board 12. There are many other ways of communicating information, such as via wireless communication, which may be electromagnetic or optical.

  It may be desirable to make switch 54 from one semiconductor material and bypass diode 44 from another semiconductor material. For example, gallium nitride (GaN) is preferred for the combined switch 54, while Si for the bypass diode 44 is preferred. These functions can be separated into separate devices as shown in FIG. 18, and the bypass diode 44 is shown adjacent and connected to the combined switch 54.

Fabrication Embodiments of the present disclosure are described in the context of solar cell 14, solar cell panel 10a, and / or satellite fabrication method 68 including the steps 70-82 shown in FIG. An artificial satellite 84 having a solar cell panel 10a consisting of cells 14 is shown in FIG.

  As shown in FIG. 19, in the pre-manufacturing stage, the exemplary method 68 may include the specification and design 70 of the solar cell 14, the solar cell panel 10a, and / or the satellite 84, and the procurement 72 of these materials. In the production stage, the production 74 of the components and subassemblies of the solar cell 14, the solar cell panel 10a, and / or the artificial satellite 84, and the system integration 76 are performed, which include the solar cell 14, the solar cell panel 10a, and And / or include the production of satellites 84. Thereafter, the solar cell 14, the solar cell panel 10a, and / or the artificial satellite 84 may go through licensing and delivery 78 to be provided for operation 80. The solar cell 14, the solar cell panel 10a, and / or the artificial satellite 84 may also be scheduled for maintenance and maintenance 82 (including remodeling, reconstruction, remodeling, etc.) prior to launch.

  Each step of method 68 may be performed or carried out by a system integrator, a third party, and / or an operator (e.g., a customer). For the purposes of this specification, a system integrator may include, but is not limited to, any number of manufacturers and major subcontractors of solar cells, solar cell panels, satellites or spacecraft, and third parties. The parties may include, but are not limited to, any number of vendors, subcontractors and suppliers, and the operators may be satellite carriers, military organizations, service agencies, etc.

  As shown in FIG. 20, the artificial satellite 84 manufactured by the exemplary method 68 may include a system 86, a body 88, a solar cell panel 10a consisting of solar cells 14, and one or more antennas 90. Examples of systems 86 included in satellite 84 include, but are not limited to, one or more of propulsion system 92, electrical system 94, communication system 96, and power system 98. Also, any number of other systems 86 may be included.

  FIG. 22 is a diagram of a solar cell panel 10a in the form of a functional block diagram, according to one example. The solar cell panel 10 a comprises a solar cell array 22 consisting of one or more of the solar cells 14 individually attached to the substrate 12. Each of the solar cells 14 absorbs light 100 from the light source 102 and in response generates an electrical output 104.

  At least one of the solar cells 14 has at least one clipped corner portion 24 defining a corner area 26, whereby the area 28 of the substrate 12 has the solar cells 14 attached to the substrate 12 Sometimes it remains exposed. When the plurality of solar cells 14 are attached to the substrate 12, the corner areas 26 of adjacent ones of the solar cells 14 are aligned, thereby exposing the area 28 of the substrate 12.

  The as-exposed area 28 of the substrate 12 includes one or more corner conductors 20 attached to the substrate 12, printed on the substrate 12, or incorporated into the substrate 12, and the solar cell 14 and One or more electrical connections between the corner conductor 20 are made in a corner area 26 made by at least one clipped corner 24 of the solar cell 14.

  The corner area 26 obtained from the clipped corner 24 is at least one contact, for example a front contact 32 on the front side of the solar cell 14 and for making an electrical connection between the corner conductor 20 and the solar cell 14 and And / or include a back contact 34 on the back side of the solar cell 14. The electrical connection includes an up / down or left / right series connection to determine the flow of power through the solar cell 14 and may include one or more bypass diodes 44.

  The exposed area 28 of the substrate 12 is a corner area 26 defined by the trimmed corner 24 adjacent to the solar cell 14 for changing the current flow path between the solar cell 14 and the electrical connection. And at least one switch 54 located within. Substrate 12 includes one or more traces connected to switch 54 to make electrical connections between solar cells 14.

  The switch 54a reconfigures the string length for electrical connection between the solar cell 14 and the switch 54b so as to divert the solar cell 14 in response to the control signal. The switch 54a also reconfigures the connections between strings, allowing for serial connection between strings and reconfigurability of outputs. Switch 54 may be a single-pole single-throw (SPST) switch, or a dual-pole single-throw (DPST) switch, or the function of bypass diode 44 It may be an integrated device that can be packaged to include functions other than such switching functions.

Experimental Results To demonstrate the reconstruction of the array string length, a solar cell array using a flex circuit board was built based on the corner conductor design.

  FIG. 22A is an image of a demonstration solar cell array consisting of 12 solar cells arranged in three stages, with four solar cells in each stage. Electrical connections are made in the corner area to provide either series connection or string termination. The current flow or conductive path was selected by welding metal foil jumpers in place. Instead of metal jumpers, pairs of wires extending beyond the perimeter of the solar cell array were added in some places.

  FIG. 22B is an image showing an enlarged view of one of the corner areas showing the electrical connections between the front contact, the back contact, the bypass diode, and the solar cell.

  FIG. 22C is a version of FIG. 22B with electrical connections between the top left solar cell and the bottom left solar cell indicated by the dark lines drawn on the conductive paths. One conductive path connects the back contact of the upper left solar cell to the front contact of the lower left solar cell so that current flows downward. Another conductive path connects the back contact of the lower left solar cell through the bypass diode.

  The electrical connection between the upper right solar cell and the lower right solar cell is 180 degrees rotated as compared to the electrical connection between the upper left solar cell and the lower left solar cell, so that Current flows from the lower right solar cell to the upper right solar cell.

  The jumpers are arranged for series connection. By changing the position of the jumper, current flow can be terminated in the buried trace.

  FIG. 22D is an image of another corner area with wires added instead of jumpers. The multiple wires could be shorted together to function like a jumper, or the wires could be separated to function without a jumper.

  In this demonstration, using jumpers or wires, the configuration of a solar cell array with 12 solar cells from two strings with six solar cells, three strings with four solar cells Can be changed to

  FIG. 22E is a graph of the photocurrent-voltage (LIV) measurement of a solar cell array under AM0 (air mass coefficient to zero atmosphere) illumination, with two strings of six solar cells, and four Made in a three string configuration with a solar cell. A change in voltage confirms a change in string length.

  FIG. 22F is an image of the demonstration solar cell array of FIG. 22A, with the central four solar cells being covered to prevent their operation.

  FIG. 22G is a graph of LIV measurement of a solar cell array under AM0 illumination, with measurements of the configuration shown in FIG. 22F taken with the four central solar cells covered to prevent their operation The Covering a solar cell is an experimental way to simulate damage to a solar cell where the solar cell has reduced current or voltage output.

  In this example, the solar cell array is configured to have three strings, each having four solar cells. Data for strings 1, 2 and 3 are shown for both covered and uncovered cases. When uncovered, the three strings have similar outputs with voltages close to 11V. When covered, two strings lose solar cells and one string loses two solar cells. The loss of this solar cell is reflected in the loss of voltage. The vertical line of Vload represents the load voltage at which current is collected by the power system. With this selection of load voltage, the load current will drop to almost zero.

  FIG. 22H is a graph of LIV measurements of solar cell arrays under AM0 illumination, with measurements of the configuration shown in FIG. 22F taken with the four central solar cells covered to prevent their operation. The

  In this example, the solar cell array is configured to have two strings, each having six solar cells, wherein the six solar cells increase the power output of the strings. With the four central solar cells covered to prevent their operation, there are four solar cells in operation and two cells not operating in each string. The current needs to flow through the bypass diodes of the non-operating solar cell, so the voltage output of the string is the four solar cells in operation minus the two bypass diodes.

  The data in FIG. 22H shows the data of the original string before the four central solar cells were covered. Then, when the middle four solar cells are covered, the voltage drops to the level indicated by the damaged string.

  Reconfiguring to string lengths of six solar cells increases the voltage and power output of resilient strings 1 and 2. Similar to FIG. 22G, the vertical line of Vload represents the load voltage. In the case of resilient strings 1 and 2, the load current is now about the same as the original string.

  The power from the four central solar cells covered is of course still lost. However, with conventional solar cell arrays, damage to four of the twelve solar cells will substantially eliminate the current at the load supplied to the power system. In this example, by reconfiguring the solar cell array, power from each solar cell can be supplied to the power system with near optimal collection. Specifically, the original string supplies 2.2 watts per solar cell at the load voltage, but when the central four solar cells are covered, the damaged string drops to 0.1 watts per solar cell Do. After reconfiguration, elastic strings 1 and 2 can provide 2.1 watts per working solar cell.

  The power output could be improved by adding another switch connecting the front and back contacts of the solar cells in the array. By doing this, the current will cause non-functional solar cells in the array to bypass through the switch without power loss. However, the solar cell array in this demonstration does not provide this function, so there is a power loss into the bypass diode.

Furthermore, the present disclosure includes embodiments according to the following clauses.
Clause 1. The substrate includes one or more solar cells attached to a substrate, the substrate including one or more electrical connections to the solar cells, the substrate being one of the electrical connections to one or more of the solar cells A solar cell array comprising one or more switches for diverting one or more.
Clause 2. When at least one of the solar cells having one or more clipped corners is attached to the substrate, the area of the substrate remains exposed and the area of the substrate that remains exposed is at least one of the switches. Solar cell array according to clause 1 including one.
Clause 3. At least one of the solar cells is attached to the substrate such that the corner area defined by the pruned corners of at least one of the solar cells is aligned, thereby exposing the area of the substrate The solar cell array according to clause 2.
Clause 4. The solar cell array according to clause 3, wherein at least one of the switches is located in a corner area defined by clipped corners adjacent to at least one of the solar cells.
Clause 5. The solar cell array of any one of clauses 1 to 4, wherein the switch diverts current away from one or more of the solar cells.
Clause 6. The solar cell array according to any one of clauses 1 to 5, wherein the solar cell, one or more bypass diodes, and the switch are electrically in parallel.
Clause 7. 6. A solar cell array according to any of the preceding clauses, wherein the switch is controlled by one or more control signals.
Clause 8. The switch, when closed, connects one or more front and back contacts of the solar cell, and the current bypasses one or more of the solar cells, any one of clauses 1 to 7 Solar cell array described in.
Clause 9. The solar cell array of any of clauses 1 to 8, further comprising one or more switches for adding or removing one or more of the solar cells from the string of solar cells.
Clause 10. 11. The solar cell array of clause 9, wherein the length of the string is varied to change the voltage generated by the string.
Clause 11. 11. A solar cell array according to any of the preceding clauses, wherein the electrical connection comprises one or more conductors on or in the substrate.
Clause 12. 12. A solar cell array according to any of the clauses 1 to 11, wherein the substrate comprises one or more traces connected to a bypass switch for making an electrical connection between the solar cells.
Clause 13. Including attaching one or more solar cells to the substrate, the substrate including one or more electrical connections to the solar cells, the substrate being one of the electrical connections to one or more of the solar cells A method for manufacturing a solar cell array, comprising one or more switches for diverting one or more.
Clause 14. When at least one of the solar cells having one or more clipped corners is attached to the substrate, the area of the substrate remains exposed and the area of the substrate that remains exposed is at least one of the switches The method of clause 13 including one.
Clause 15. At least one of the solar cells is attached to the substrate such that the corner area defined by the pruned corners of at least one of the solar cells is aligned, thereby exposing the area of the substrate Method according to clause 14.
Clause 16. The method according to clause 15, wherein at least one of the switches is located in a corner area defined by clipped corners adjacent to at least one of the solar cells.
Clause 17. The method according to any one of clauses 13 to 16, wherein the switch causes the current to bypass the one or more of the solar cells.
Clause 18. 22. The method according to any one of clauses 13 to 17, wherein the solar cell, one or more bypass diodes, and the switch are electrically in parallel.
Clause 19. 22. A method according to any one of clauses 13 to 18, wherein the switch is controlled by one or more control signals.
Clause 20. The switch, when closed, connects one or more front and back contacts of the solar cell, and the current bypasses one or more of the solar cells, any one of clauses 13 to 19. The method described in.
Clause 21. In any one of clauses 13 to 20, further comprising adding one or more of the solar cells to the string of solar cells or removing them from the string of solar cells using one or more switches Method described.
Clause 22. 22. The method of clause 21 wherein the length of the string is changed to change the voltage generated by the string.
Clause 23. The method according to any one of clauses 13 to 22, wherein the electrical connection comprises one or more conductors on or in the substrate.
Clause 24. 14. The method according to any one of clauses 13-23, wherein the substrate comprises one or more traces connected to a bypass switch to make an electrical connection between solar cells.
Clause 25. Controlling one or more switches in one or more electrical connections to one or more solar cells to divert one or more of the electrical connections to one or more of the solar cells How to operate a solar cell array, including:

Conclusion The descriptions of the above embodiments have been presented for purposes of illustration and description, and are not intended to be exhaustive or to limit the embodiments described. Many alternatives, modifications, and variations may be used instead of the specific elements described above.

Claims (25)

Comprising one or more solar cells (14) attached to a substrate (12),
The substrate includes one or more electrical connections to the solar cell;
A solar cell array, wherein the substrate comprises one or more switches (54) for diverting one or more of the electrical connections to one or more of the solar cells. When at least one of the solar cells (14) having one or more clipped corners (24) is attached to the substrate, the area (28) of the substrate (12) remains exposed.
The solar cell array of claim 1, wherein the area of the substrate that remains exposed comprises at least one of the switches (54a) (54b).   The corner area (26) defined by the clipped corner (24) of the at least one of the solar cells (14) is aligned, whereby the area (28) of the substrate (12) is aligned. The solar cell array of claim 2, wherein the at least one of the solar cells (14) is attached to the substrate (12) so as to expose.   Said at least one of said switches (54) being located within said corner area (26) defined by said clipped corner (24) adjacent to said at least one of said solar cells The solar cell array according to Item 3.   The solar cell array of any of the preceding claims, wherein the switch (54) diverts current away from one or more of the solar cells.   Solar cell array according to any one of the preceding claims, wherein the solar cell, one or more bypass diodes (44) and the switch are electrically in parallel.   The solar cell array according to any one of the preceding claims, wherein the switch (54) is controlled by one or more control signals.   The switch (54), when closed, connects the one or more front contacts (32) and back contacts (34) of the solar cell (14), and a current flows through the one of the solar cells The solar cell array according to any one of claims 1 to 7, wherein a plurality of solar cells are avoided.   9. One or more switches (54) for adding or removing one or more of the solar cells to or from the string of solar cells. Solar cell array described in.   The solar cell array of claim 9, wherein the length of the string is varied to change the voltage generated by the string.   A solar cell array according to any of the preceding claims, wherein the electrical connection comprises one or more conductors (20) on or in the substrate (12).   12. A substrate according to any one of the preceding claims, wherein the substrate (12) comprises one or more traces connected to a bypass switch (54b) for making the electrical connection between the solar cells (14). Solar cell array described in. A method of operating a solar cell array, comprising
One or more of the one or more electrical connections to one or more solar cells (14) for diverting one or more of the electrical connections to one or more of the solar cells Controlling the switch (54). A method for manufacturing a solar cell array, comprising
Including attaching one or more solar cells (14) to the substrate (12),
The substrate includes one or more electrical connections to the solar cell;
A method, wherein the substrate comprises one or more switches (54) for diverting one or more of the electrical connections to one or more of the solar cells. When at least one of the solar cells (14) having one or more clipped corners (24) is attached to the substrate, the area (28) of the substrate (12) remains exposed.
The method of claim 14, wherein the area of the substrate that remains exposed comprises at least one of the switches (54).   The corner area (26) defined by the clipped corner (24) of the at least one of the solar cells (14) is aligned, thereby exposing the area (28) of the substrate The method according to claim 15, wherein the at least one of the solar cells (14) is attached to the substrate (12).   The at least one of the switches (54) is located in the corner area (26) defined by the clipped corner (24) adjacent to the at least one of the solar cells (14) The method according to claim 16, wherein   The method according to any one of claims 14 to 17, wherein the switch (54) diverts current away from one or more of the solar cells (14).   The method according to any one of claims 14 to 18, wherein the solar cell (14), one or more bypass diodes (44), and the switch (54) are electrically in parallel.   20. A method according to any one of claims 14 to 19, wherein the switch (54) is controlled by one or more control signals.   The switch (54), when closed, connects the one or more front and back contacts of the solar cell (14), and a current bypasses the one or more of the solar cells 21. A method according to any one of claims 14 to 20.   Claiming further comprising adding one or more of the solar cells (14) to the string of solar cells or removing them from the string of solar cells using one or more switches (54) A method according to any one of items 14 to 21.   23. The method of claim 22, wherein the length of the string is varied to change the voltage generated by the string.   24. A method according to any one of claims 14 to 23, wherein the electrical connection comprises one or more conductors (20) on or in the substrate (12). 25. A substrate according to any one of claims 14 to 24, wherein the substrate (12) comprises one or more traces connected to a bypass switch (54b) for making the electrical connection between the solar cells (14). The method described in.