Abstract:
A solar cell management system for increasing the efficiency and power output of a solar cell and methods for making and using the same. The management system provides an electric field across one or more solar cells. The imposed electric field exerts a force on both the electrons and holes created by light incident on the solar cell and accelerates the electron-hole pairs towards the electrodes of the solar cell. The solar cell management system considers variations in configuration of solar cells to maximize the power output of the solar cells. The accelerated electron-hole pairs have a lower likelihood of recombining within the cells&#39; semiconductor&#39;s material. This reduction in the electron-hole recombination rate results in an overall increase in the solar cells&#39; efficiency and greater power output.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a divisional application of co-pending U.S. patent application Ser. No. 14/637,353, filed on Mar. 3, 2015, which is a continuation-in-part of and claims the benefit of U.S. patent application Ser. No. 14/628,079, filed Feb. 20, 2015, which claims the benefit of U.S. Provisional Application No. 61/943,127, filed Feb. 21, 2014; U.S. Provisional Application No. 61/943,134, filed Feb. 21, 2014; U.S. Provisional Application No. 61/947,326, filed Mar. 3, 2014; and U.S. Provisional Application No. 62/022,087, filed Jul. 8, 2014, the disclosures of which are hereby incorporated by reference in their entireties and for all purposes. 
     
    
     FIELD 
       [0002]    The present disclosure relates generally to photovoltaic devices and more specifically, but not exclusively, to systems and methods for maximizing the power or energy generated and the overall efficiency of one or more solar cells, for example, by applying and adjusting an external electric field across the solar cells. 
       BACKGROUND 
       [0003]    A solar cell (also called a photovoltaic cell) is an electrical device that converts the energy of light directly into electricity by a process known as “the photovoltaic effect.” When exposed to light, the solar cell can generate and support an electric current without being attached to any external voltage source. 
         [0004]    The most common solar cell consists of a p-n junction  110  fabricated from semiconductor materials (e.g., silicon), such as in a solar cell  100  shown in  FIG. 1 . For example, the p-n junction  110  includes a thin wafer consisting of an ultra-thin layer of n-type silicon on top of a thicker layer of p-type silicon. Where these two layers are in contact, an electrical field (not shown) is created near the top surface of the solar cell  100 , and a diffusion of electrons occurs from the region of high electron concentration (the n-type side of the p-n junction  110 ) into the region of low electron concentration (the p-type side of the p-n junction  110 ). 
         [0005]    The p-n junction  110  is encapsulated between two conductive electrodes  101   a ,  101   b . The top electrode  101   a  is either transparent to incident (solar) radiation or does not entirely cover the top of the solar cell  100 . The electrodes  101   a ,  101   b  can serve as ohmic metal-semiconductor contacts that are connected to an external load  30  that is coupled in series. Although shown as resistive only, the load  30  can also include both resistive and reactive components. 
         [0006]    When a photon hits the solar cell  100 , the photon either: passes straight through the solar cell material—which generally happens for lower energy photons; reflects off the surface of the solar cell; or preferably is absorbed by the solar cell material—if the photon energy is higher than the silicon band gap—generating an electron-hole pair. 
         [0007]    If the photon is absorbed, its energy is given to an electron in the solar cell material. Usually this electron is in the valence band and is tightly bound in covalent bonds between neighboring atoms, and hence unable to move far. The energy given to the electron by the photon “excites” the electron into the conduction band, where it is free to move around within the solar cell  100 . The covalent bond that the electron was previously a part of now has one fewer electron—this is known as a hole. The presence of a missing covalent bond allows the bonded electrons of neighboring atoms to move into the hole, leaving another hole behind. In this way, a hole also can move effectively through the solar cell  100 . Thus, photons absorbed in the solar cell  100  create mobile electron-hole pairs. 
         [0008]    The mobile electron—hole pair diffuses or drifts toward the electrodes  101   a ,  101   b . Typically, the electron diffuses/drifts towards the negative electrode, and the hole diffuses/drifts towards the positive electrode. Diffusion of carriers (e.g., electrons) is due to random thermal motion until the carrier is captured by electrical fields. Drifting of carriers is driven by electric fields established across an active field of the solar cell  100 . In thin film solar cells, the dominant mode of charge carrier separation is drifting, driven by the electrostatic field of the p-n junction  110  extending throughout the thickness of the thin film solar cell. However, for thicker solar cells having virtually no electric field in the active region, the dominant mode of charge carrier separation is diffusion. The diffusion length of minor carriers (i.e., the length that photo-generated carriers can travel before they recombine) must be large in thicker solar cells. 
         [0009]    Ultimately, electrons that are created on the n-type side of the p-n junction  110 , “collected” by the p-n junction  110 , and swept onto the n-type side can provide power to the external load  30  (via the electrode  101   a ) and return to the p-type side (via the electrode  101   b ) of the solar cell  100 . Once returning to the p-type side, the electron can recombine with a hole that was either created as an electron-hole pair on the p-type side or swept across the p-n junction  110  from the n-type side. 
         [0010]    As shown in  FIG. 1 , the electron-hole pair travels a circuitous route from the point the electron-hole pair is created to the point where the electron-hole pair is collected at the electrodes  101   a ,  101   b . Since the path traveled by the electron-hole pair is long, ample opportunity exists for the electron or hole to recombine with another hole or electron, which recombination results in a loss of current to any external load  30 . Stated in another way, when an electron-hole pair is created, one of the carriers may reach the p-n junction  110  (a collected carrier) and contribute to the current produced by the solar cell  100 . Alternatively, the carrier can recombine with no net contribution to cell current. Charge recombination causes a drop in quantum efficiency (i.e., the percentage of photons that are converted to electric current when the solar cell  100 ), and, therefore, the overall efficiency of the solar cell  100 . 
         [0011]    Recent attempts to reduce the cost and increase the efficiency of solar cells include testing various materials and different fabrication techniques used for the solar cells. Another approach attempts to enhance the depletion region formed around the p-n junction  110  for enhancing the movement of charge carriers through the solar cell  100 . For example, see U.S. Pat. No. 5,215,599, to Hingorani, et al. (“Hingorani”), filed on May 3, 1991, and U.S. Pat. No. 8,466,582, to Fornage (“Fornage”), filed on Dec. 2, 2011, claiming priority to a Dec. 3, 2010 filing date, the disclosures of which are hereby incorporated by reference in their entireties and for all purposes. 
         [0012]    However, these conventional approaches for enhancing the movement of charge carriers through the solar cell  100  require a modification of the fundamental structure of the solar cell  100 . Hingorani and Fornage, for example, disclose applying an external electric field to the solar cell using a modified solar cell structure. The application of the external electric field requires a voltage to be applied between electrodes inducing the electric field (described in further detail with reference to equation 2, below). Without modifying the fundamental structure of the solar cell  100 , applying the voltage to the existing electrodes  101   a ,  101   b  of the solar cell  100  shorts the applied voltage through the external load  30 . Stated in another way, applying voltage to the electrodes  101   a ,  101   b  of the solar  100  is ineffective for creating an external electric field and enhancing the movement of charge carriers. Accordingly, conventional approaches—such as disclosed in Hingoriani and Fornage—necessarily modify the fundamental structure of the solar cell  100 , such as by inserting an external (and electrically isolated) set of electrodes on the base of the solar cell  100 . There are several disadvantages with this approach. 
         [0013]    For example, the external electrodes must be placed on the solar cell  100  during the fabrication process—it is virtually impossible to retrofit the external electrodes to an existing solar cell or panel. This modification to the fabrication process significantly increases the cost of manufacturing and decreases the manufacturing yield. Additionally, placement of the external electrodes over the front, or incident side, of the solar cell  100  reduces the optical energy which reaches the solar cell  100 , thereby yielding a lower power output. 
         [0014]    As a further disadvantage, to yield significant improvements in power output of the solar cell  100 , sizeable voltages must be applied to the external electrodes of the solar cell  100 . For example, Fornage discloses that voltages on the order of “1,000′s” of volts must be placed on the external electrodes for the applied electric field to be effective and increase the power output of the solar cell  100 . The magnitude of this voltage requires special training for servicing as well as additional high voltage equipment and wiring that does not presently exist in existing or new solar panel deployments. As an example, an insulation layer between the external electrodes and the solar cell  100  must be sufficient to withstand the high applied voltage. In the event of a failure of the insulation layer, there is a significant risk of damage to not only the solar cell  100 , but also all solar cells  100  connected in series or parallel to the failed solar cell as well as the external load  30 . 
         [0015]    As a further disadvantage, typical installation of the solar cell  100  can introduce additional factors—such as additional wiring, external hardware, and so on—that can affect the power output of the solar cell  100 . For example, multiple solar cells  100  can be coupled (in series and/or parallel) together to form a solar panel  10  (shown in  FIGS. 2A-D ). Each solar panel  10  can then be coupled using any suitable means described herein, including in parallel, series, or a combination thereof. With reference to  FIGS. 2A-D , typical installation configurations using at least one solar panel  10  are shown. 
         [0016]    The solar panels  10  can be connected in either parallel ( FIG. 2A ), series ( FIG. 2B ), or a combination thereof ( FIG. 2C ). In each of  FIGS. 2A-C , the solar panels  10  can drive a load, such as an inverter  31 .  FIG. 2A  shows a series coupling of the solar panels  10 . Turning to  FIG. 2B , the solar panels  10  are shown connected in series and drives the inverter  31 .  FIG. 2C  shows an alternative installation of the solar panels  10  connected both in parallel and in series. In yet another embodiment,  FIG. 2D  shows an installation—typically found in many residential installations—where each of the solar panels  10  are connected to its own inverter  31 . 
         [0017]    Each method of connecting the solar cells  100  and the solar panels  10  requires different wiring and installation methods that change the electrical characteristics/behavior, and the corresponding power output, of the connected solar panels  10 . Conventional efforts to increase the efficiency of solar cells rarely account for installation obstacles, such as the various methods for connecting multiple solar cells  100  and/or multiple solar panels  10 . 
         [0018]    In view of the foregoing, a need exists for an improved solar cell system and method for increased efficiency and power output, such as with increased mobility of electron-hole pairs, in an effort to overcome the aforementioned obstacles and deficiencies of conventional solar cell systems. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]      FIG. 1  is an exemplary top-level cross-sectional diagram illustrating an embodiment of a solar cell of the prior art. 
           [0020]      FIG. 2A  is an exemplary top-level block diagram illustrating one embodiment of a solar panel array of the prior art using the solar cells of  FIG. 1 . 
           [0021]      FIG. 2B  is an exemplary block diagram illustrating an alternative embodiment of a solar panel array of the prior art using the solar cells of  FIG. 1 , wherein each solar panel is coupled in series. 
           [0022]      FIG. 2C  is an exemplary block diagram illustrating an alternative embodiment of a solar panel array of the prior art using the solar cells of  FIG. 1 , wherein each solar panel is coupled both in series and in parallel. 
           [0023]      FIG. 2D  is an exemplary block diagram illustrating an alternative embodiment of a solar panel array of the prior art using the solar cells of  FIG. 1 , wherein each solar panel is directly coupled to a load. 
           [0024]      FIG. 3  is an exemplary top-level block diagram illustrating an embodiment of a solar cell management system. 
           [0025]      FIG. 4  is an exemplary block diagram illustrating an embodiment of the solar cell management system of  FIG. 3 , wherein a solar panel array is wired in parallel according to the arrangement shown in  FIG. 2A  and coupled to a voltage source through a switch. 
           [0026]      FIG. 5  is an exemplary block diagram illustrating an alternative embodiment of the solar cell management system of  FIG. 3 , wherein a solar panel array is wired in parallel according to the arrangement shown in  FIG. 2A  and coupled to a voltage pulser circuit. 
           [0027]      FIG. 6  is an exemplary block diagram illustrating an alternative embodiment of the solar cell management system of  FIG. 4 , wherein the solar panel array is coupled in series according to the arrangement shown in  FIG. 2B . 
           [0028]      FIG. 7  is a graph illustrating an applied voltage V APP  relative to the voltage across each solar panel of the solar cell management system of  FIG. 6 . 
           [0029]      FIG. 8  is an exemplary block diagram illustrating an alternative embodiment of the solar cell management system of  FIG. 6 , wherein one or more of the solar panel arrays are coupled to a voltage source through one or more switches. 
           [0030]      FIG. 9  is an exemplary block diagram illustrating another alternative embodiment of the solar cell management system of  FIG. 4 , wherein one or more of the solar panel arrays are coupled to the voltage source through one or more switches. 
           [0031]      FIG. 10  is an exemplary block diagram illustrating another alternative embodiment of the solar cell management system of  FIG. 4 , wherein one or more of the solar panel arrays are wired both in series and parallel according to the arrangement shown in  FIG. 2D  and are coupled to the voltage source through a switch. 
           [0032]      FIG. 11  is an exemplary block diagram illustrating another alternative embodiment of the solar cell management system of  FIG. 10 , wherein one or more of the solar panel arrays are coupled to the voltage source through one or more switches. 
           [0033]      FIG. 12A-B  are exemplary block diagrams illustrating alternative embodiments of the solar cell management system of  FIG. 4  cooperating with the solar panel array of  FIG. 2E . 
           [0034]      FIG. 13  is an exemplary block diagram illustrating an alternative embodiment of the solar cell management system of  FIG. 5 , wherein the solar panel array is wired in series according to the solar panel array of  FIG. 2B . 
           [0035]      FIG. 14  is a graph illustrating an applied voltage V APP  relative to the voltage across each solar panel of the solar cell management system of  FIG. 13 . 
           [0036]      FIGS. 15A-B  are exemplary block diagrams illustrating alternative embodiments of the solar cell management system of  FIG. 13 , wherein one or more of the solar panel arrays are coupled to one or more voltage pulsers. 
           [0037]      FIG. 16  is an exemplary block diagram illustrating an alternative embodiment of the solar cell management system of  FIG. 5 , wherein the solar panel array is wired according to the arrangement shown in  FIG. 2C . 
           [0038]      FIGS. 17A-B  are exemplary block diagrams illustrating alternative embodiments of the solar cell management system of  FIG. 5 , wherein the solar panel array is wired according to the arrangement shown in  FIG. 2D . 
           [0039]      FIG. 18  is an exemplary circuit diagram illustrating an embodiment of a pulse uplift circuit for use with the solar cell management system of  FIG. 5 . 
       
    
    
       [0040]    It should be noted that the figures are not drawn to scale and that elements of similar structures or functions are generally represented by like reference numerals for illustrative purposes throughout the figures. It also should be noted that the figures are only intended to facilitate the description of the preferred embodiments. The figures do not illustrate every aspect of the described embodiments and do not limit the scope of the present disclosure. 
       DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0041]    Since currently-available solar cell systems fail to maximize the power output of a photovoltaic cell, a solar cell system that increases the mobility of electron-hole pairs and reduces the recombination current in a semiconductor material can prove desirable and provide a basis for a wide range of solar cell systems, such as to increase the efficiency and power output of solar cells configured as a solar panel. This result can be achieved, according to one embodiment disclosed herein, by a solar cell management system  300  as illustrated in  FIG. 3 . 
         [0042]    Turning to  FIG. 3 , the solar cell management system  300  is suitable for use with a wide range of photovoltaic devices. In one embodiment, the solar cell management system  300  can be suitable for use with the solar cell  100  shown in  FIG. 1 . For example, the solar cell  100  can represent any suitable generation of solar cells such as wafer-based cells of crystalline silicon (first generation), thin film solar cells including amorphous silicon cells (second generation), and/or third generation cells. The solar cell management system  300  advantageously can be used with any generation of solar cell  100  without structural modification—and the associated drawbacks. 
         [0043]    In another embodiment, the solar cell management system  300  can be suitable for use with multiple solar cells  100 , such as the solar panels  10  shown in  FIGS. 2A-D . As previously discussed, multiple solar cells  100  can be coupled (in series and/or parallel) together to form a solar panel  10 . The solar panels  10  can be mounted on a supporting structure (not shown) via ground mounting, roof mounting, solar tracking systems, fixed racks, and so on and can be utilized for both terrestrial and space borne applications. Similarly, the solar cell management system  300  advantageously can be used with any generation of solar panel  10  without structural modification—and the associated drawbacks—of the solar panel  10 . 
         [0044]    As shown in  FIG. 3 , the photovoltaic device  200  cooperates with an electric field  250 . In some embodiments, the polarity of the electric field  250  can be applied in either the same direction or the reverse direction as the polarity of the electrodes  101   a ,  101   b  (shown in  FIG. 1 ) in the photovoltaic device  200 . For example, if applying the electric field  250  in the same direction as the polarity of the electrodes  101   a ,  101   b  in the photovoltaic device  200 , the electric field  250  acts on the electron-hole pairs in the photovoltaic device  200  to impose a force—e − E or h + E on the electron or hole, respectively—thereby accelerating the mobility of the electron and hole towards respective electrodes. Alternatively, if the polarity of the electric field  250  is reversed, the mobility of the electron-hole pairs in the photovoltaic device  200  decreases, thereby increasing the recombination current within the photovoltaic device  200 . Accordingly, the efficiency of the photovoltaic device  200  can be diminished as desired, such as for managing the power output of the photovoltaic device  200 . 
         [0045]    Furthermore, the electric field  250  applied to the photovoltaic device  200  can be static or time varying as desired. In the case where the electric field  250  is time varying, the electric field  250  has a time averaged magnitude that is non-zero. Stated in another way, the net force on the electrons and holes is non-zero to provide increased mobility in the electron-hole pairs of the photovoltaic device  200 . 
         [0046]    The solar cell management system  300  can apply the external voltage V App  to the photovoltaic device  200  using any suitable means described herein, including using a switch  55  as shown in  FIG. 4 . Turning to  FIG. 4 , the photovoltaic device  200  can represent any number of photovoltaic devices such as the solar cell  100  and/or the solar panels  10  as illustrated. The solar panels  10  are shown to be wired in parallel (also shown in  FIG. 2A ) and are connected to the switch  55 , such as a single pole, double throw (or three-way) switch. However, as will be discussed with reference to  FIGS. 6 and 8-12 , the solar panels  10  also can be wired in series, a combination of series and parallel, and independently from one another. In one embodiment, the switch  55  is also coupled to a voltage source  50  and an external load R L  (e.g., shown as the inverter  31 ). The inverter  31  can include both resistive and reactive components. In some embodiments, the inverter  31  can convert a DC voltage and current into an AC voltage and current, which is typically compatible in voltage and frequency with conventional AC power grids. The output frequency of the inverter  31  and the amplitude of the AC current/voltage can be based upon country, location, and local grid requirements. 
         [0047]    The voltage source  50  can include any suitable means for maintaining a constant voltage, including ideal voltage sources, controlled voltage sources, and so on. However, in some embodiments, the voltage source  50  can have a variable, adjustable output (e.g., time varying voltage). A switch control (or controller)  45  is coupled to the switch  55  to control the duration of connection and/or the frequency of switching, such as between the voltage source  50  and the inverter  31  to the solar panels  10 . The switch controller  45  can be preset to operate at a fixed switching duration D and switching frequency f. In some embodiments, the magnitude of the voltage V App  applied by voltage source  50 , the duration D of connection, and/or the frequency f of switching can be preset and/or vary based on load conditions. 
         [0048]    For example, the switch  55  connects the solar panels  10  with the voltage source  50  in a first position (as shown with the arrow in the switch  55  of  FIG. 4 ). When connected in the first position, the voltage source  50  applies the voltage V APP  across the electrodes  101   a ,  101   b  (shown in  FIG. 1 ) of the solar panels  10  and induces the electric field  250  (shown in  FIG. 3 ) across each solar panel  10 . Once the electric field  250  has been established across the solar panels  10 , the switch  55  switches to connect the solar panels  10  to the inverter  31  (i.e., the load R L ) in a second position. Accordingly, the voltage source  50  can provide the electric field  250  without being connected to the solar panels  10  and the inverter  31  at the same time. Therefore, applying the external voltage V APP  does not allow the load R L  (e.g., the inverter  31 ) to draw current directly from the voltage source  50 . 
         [0049]    Application of the electric field  250  to the solar panels  10  can increase the current and power output of the solar panels  10  by a predetermined amount when the solar panels  10  subsequently are connected to the inverter  31  in the second position. The predetermined amount is dependent upon an intensity of light incident on the solar panels  10 , the voltage applied V APP  to the solar panels  10  by the voltage source  50 , the thickness of the solar panels  10 , the frequency f that the voltage source  50  is connected to the solar panels  10 , and the duty cycle of the switching process between the first position and the second position—with the duty cycle being defined as the amount of time that the solar panels  10  are connected to the voltage source  50  divided by 1/f the switching time (i.e., multiplied by the frequency f or divided by the total period of the signal). It should be noted that the switch duration time D, the switching frequency f, and the duty cycle are all interrelated quantities such that quantifying any two of the quantities allows for determination of the third quantity. For example, specifying the switching frequency and the duty cycle allows for determination of the switch duration time D. For example, under high intensity light conditions, the improvement in power output can be on the order of 20%; under low light conditions, 50+%. 
         [0050]    The embodiment shown in  FIG. 4  advantageously provides the electric field  250  to the photovoltaic device  200  without the need to modify the solar panels  10  and/or solar cells  100  to include additional, external electrodes. 
         [0051]    In some embodiments, an energy storage device—such as a capacitor  41 , an inductor  42 , and/or a battery  43 —can be placed before the inverter  31  to mitigate any voltage drop-out being seen by the inverter  31  while the switch  55  is in the first position. Accordingly, while the inverter  31  (i.e., load) is disconnected from the solar panels  10  when the switch  55  is in the first position and the electric field  250  is being established across the solar panels  10 , the energy storage device supplies energy to the inverter  31  to keep current flowing during this switched period. Stated in another way, the energy storage device can discharge while the solar panels  10  are disconnected from the inverter  31 . 
         [0052]    Therefore, a constant voltage from the voltage source  50 —which in turn creates the electric field  250 —need not be applied continuously to see an improvement in the power output of the solar panels  10 . For example, with duration switching times D of nominally 10-2000 ns, V App ′s of nominally 100-500+ Volts, and a switching frequency f of 20 μ seconds, the duty cycle of nominally 0.1-10% can be used. The inductor  42 , the capacitor  41 , and/or the battery  43  are chosen to be of sufficient size to provide enough discharge while the solar panels  10  are disconnected while the electric field  250  is being placed across the solar panels  10  so as not to cause a drop out on the output of the inverter  31 . 
         [0053]      FIG. 5  illustrates an alternative embodiment of the solar cell management system  300  of  FIG. 3 . Turning to  FIG. 5 , the photovoltaic device  200  can represent any number of photovoltaic devices such as the solar cell  100  and/or the solar panels  10  as illustrated. As shown, the solar panels  10  are wired in parallel (also shown in  FIG. 2A ), but can also be wired in series and any combination thereof as will be discussed with reference to  FIGS. 13 and 15-17 . 
         [0054]    A voltage pulser  60 , such as a high voltage pulse generator, can apply a time varying voltage pulse across one or more of the solar panels  10 . In one embodiment, a duration D P  of the voltage pulse can be short—nominally 10-2000 ns—and a magnitude can be high—nominally 100-500+ Volts. In the embodiment shown in  FIG. 5 , the voltages applied, the pulse width, and the pulse repetition rate are fixed at a predetermined level to provide optimum performance under selected operating conditions. For example, the voltage pulse can have the duration D P  of about 1000 ns, which voltage pulse is repeated with a period of 1/f The duration D P  of the voltage pulse and the frequency f of the voltage pulse are chosen such that the reactance of inductors in the voltage inverter  31  present a high impedance to the voltage pulser  60 , which high impedance allows a high voltage to be developed across the electrodes  101   a ,  101   b  (shown in  FIG. 1 ) of the solar panels  10  and not be shorted out by the inverter  31 . 
         [0055]    Additionally, series inductors (not shown) can be placed at the input of the inverter  31 , which series inductors are capable of handling the current input to the inverter  31  and act as an RF choke such that the voltage pulses are not attenuated (or effectively shorted) by the resistive component of the inverter  31 . The duty cycle (time the pulse is on/time the pulse is off) can be nominally 0.1-10%. 
         [0056]    The strength of the electric field  250  imposed on the photovoltaic device  200  is a function of the construction of the photovoltaic device  200 , such as the thickness of the photovoltaic device  200 , the material and dielectric constant of the photovoltaic device  200 , the maximum breakdown voltage of the photovoltaic device  200 , and so on. 
         [0057]    As previously discussed, the photovoltaic device  200  can include any number of solar cells  100  and/or solar panels  10 , each solar cell  100  and solar panel  10 , for example, being coupled in parallel, series, and/or a combination thereof In some embodiments, imposing the electric field  250  on a selected photovoltaic device  200  can account for the variations in configuration of the photovoltaic device  200 . 
         [0058]    For each installation option discussed with reference to  FIGS. 2A-D , the solar cell management system  300  can apply the external voltage V App  to the photovoltaic device  200 . For example, using the switch  55  of  FIG. 4 , the solar cell management system  300  also can apply the external voltage V App  to the solar panels  10  that are connected in series (shown in  FIG. 2B ) and both series and parallel (shown in  FIG. 2C ). Turning to  FIG. 6 , the solar panels  10  are wired in series and connected to the switch  55 , such as the single pole, double throw (or three-way) switch of  FIG. 4 . In one embodiment, the switch  55  is also coupled to the voltage source  50  and the external load R L  (e.g., shown as the inverter  31 ). 
         [0059]    In  FIG. 6 , the electric field  250  (shown in  FIG. 3 ) applied across each solar panel  10  must be greater than a predetermined minimum electric field E min . Accordingly, the applied external voltage V App  applied to each solar panel  10  must be greater than a predetermined minimum applied voltage V min . In some embodiments, the external voltage V App  applied to each solar panel  10  must also be less than a maximum applied voltage V max  to avoid a voltage breakdown and damage to the solar panel  10  or, at least, damage to one or more solar cells  100  of the solar panels  10 . Stated in another way, Equation 1 represents the upper and lower bounds of the applied external voltage V App . 
         [0000]        V   max   &gt;V   APP   &gt;V   min   &gt;kV   P ,   (Equation 1)
 
         [0060]    In Equation 1, V P  is the voltage output of the solar panel  10 , and k is the kth panel in the configuration. As long the relationship among the applied external voltage V App  and the minimum/maximum applied voltages of Equation 1 holds true, the switch  55  can the effectively apply the electric field  250  across each solar panel  10 . 
         [0061]      FIG. 7  illustrates the external voltage V App  relative to the voltage measured across each successive solar panel  10  (e.g., from node A across nodes B, C . . . N) shown in  FIG. 6  while the switch  55  is in the second position. As shown in  FIG. 7 , the voltage across each solar panel  10  increases by the voltage output of the solar panel  10 . For example, each solar panel  10  generates a voltage of approximately twenty-four volts and that a voltage measured between the node A and any measurement node is approximately k×24 Volts, where k is the number of the solar panels  10  across which the voltage is being measured. If the inequality of the Equation 1 cannot be satisfied, the embodiment shown in  FIG. 6  can be modified to include additional switches  55 . For example, in one embodiment, a second switch  55  (switch  55   b ) can be coupled into the series of the solar panels  10  as shown in  FIG. 8 . However, more than one switch  55  (i.e., switch  55   a ,  55   b  . . .  55   n ) can be coupled to the solar panels  10  as desired. 
         [0062]    Turning to  FIG. 8 , a toggle switch  72  can be added between the voltage source  50  and each group of k solar panels  10 . To simplify the figures and for illustration purposes only, interconnections between different points in  FIG. 8  are designated by the bordered capital letters A and B, where A couples to A and B couples to B. The toggle switch  72  can represent a single-pole, single throw (two-way) switch. Specifically, the toggle switch  72  can include N input ports and 1 output port. The toggle switch  72  further defines an ON state and an OFF state. In the ON state, all of the N input ports are simultaneously connected to the single output port. In the OFF state, none of the input ports are connected to the single output port. The toggle switch  72  can be activated by the switch controller  45 , which also controls the switches  55   a ,  55   b , and so on. As shown in  FIG. 8 , the toggle switch  72  provides a return electrical path for the voltage source  50  when the switches  55   a ,  55   b  are in the first position (as discussed with reference to  FIG. 4 ). The toggle switch  72  is activated (the ON state) when the switches  55   a ,  55  are connected to the voltage source  50  and the electric field  250  (shown in  FIG. 3 ) is applied to the solar panels  10 . The toggle switch  72  deactivates (the OFF state) while the solar panels  10  are providing power to the inverter  31 . 
         [0063]    In a preferred embodiment, the switch control  45  can be synchronized such that switches  55   a ,  55   b  are placed in a first position simultaneously and connected to the voltage source  50 , while the toggle switch  72  is concurrently activated in the ON state. Likewise, the switch controller  45  simultaneously places the switches  55   a ,  55   b  in the second position and also deactivates the toggle switch  72  (the OFF state). In some embodiments, an energy storage device—such as the capacitor  41 , the inductor  42 , and/or the battery  43 —can be placed before the inverter  31  to mitigate any voltage drop-out being seen by the inverter  31  while the switches  55   a ,  55   b  are in the first position. 
         [0064]    As discussed with reference to  FIG. 4 , the solar cell management system  300  also can apply the external voltage V App  to the solar panels  10  that are connected in parallel. Turning to  FIG. 9 , more than one switch  55  can be controlled by the switch controller  45 . In a preferred embodiment, each of the switches  55   a ,  55   b  can be synchronized by the switch controller  45  and are connected and disconnected simultaneously. As before an energy storage device—such as the capacitor  41 , the inductor  42 , and/or the battery  43 —can be placed before the inverter  31  to mitigate any voltage drop-out being seen by the inverter  31  while the switches  55   a ,  55   b  are in the first position. 
         [0065]    Using the switch  55  of  FIG. 4 , the solar cell management system  300  also can apply the external voltage V App  to the solar panels  10  that are connected in both series and parallel (shown in  FIG. 2C ). Turning to  FIG. 10 , two or more of the solar panels  10  are shown to be wired in series. The series wired solar panels  10  are then interconnected in parallel. The number of the solar panels  10  that are wired in series and in parallel can be preselected as desired. 
         [0066]    As shown in  FIG. 10 , one or more switches  55  can be used to apply the electric field  250  (shown in  FIG. 3 ) across the solar panels  10 . If more than one switch  55  is used, the solar panels  10  can be wired as shown in  FIG. 11 . Turning to  FIG. 11 , the series wired solar panels  10  are wired in parallel and then interconnected to the switches  55   a ,  55   b . In a preferred embodiment, the switch controller  45  synchronizes the switches  55   a ,  55   b  to be disconnected from the inverter  31  simultaneously. Similarly, the switch controller  45  connects both the switches  55   a ,  55   b  to the voltage source  50  at the same time. In some embodiments, an energy storage device—such as the capacitor  41 , the inductor  42 , and/or the battery  43 —can be placed before the inverter  31  to mitigate any voltage drop-out being seen by the inverter  31  while the switches  55   a ,  55   b  are in the first position. 
         [0067]    In yet another embodiment, the solar cell management system  300  can cooperate with the solar panels typically found in many residential installations—where each of the solar panels  10  are connected to its own inverter  31  (shown in  FIG. 2D ). Turning to  FIGS. 12A-B , the switch  55  can cooperate with each solar panel  10  in a number of ways. In one embodiment,  FIG. 12A  illustrates the switch  55 , the voltage source  50 , and the switch controller  45  integrated into the inverter  31 . Because the inverter  31  is typically connected to a power source, the capacitor  41  can be placed within the inverter  31 . Alternatively, as shown in  FIG. 2D , multiple solar panels  10  are typically used in combination and each are coupled to its own inverter  31  such that the capacitor  41  is not used. In some embodiments, each inverter  31  operates independently of all other inverters  31  such that the switch  55  is not synchronized between inverters  31 . Accordingly, a momentary drop out of power on a selected solar panel does not appreciably affect the quality of power from the plurality of solar panels  10  and inverters  31 . 
         [0068]    The embodiment shown in  FIG. 12A  advantageously can be targeted at any new solar panel deployment. In an alternative embodiment with reference to  FIG. 12B , each solar panel  10  and inverter  31  pair can include its own switch  55   a - 55   n . Each switch  55  is connected to a central switch  46 , which is controlled by a switch controller  72 , and the voltage source  50 . 
         [0069]    The central switch  46  can provide two concurrent outputs to each solar panel  10 , each switch  55 , and each inverter  31 . The first output from the central switch  46  includes A 1 , B 1  . . . N 1  and activates each switch  55  into the first position as discussed with reference to  FIG. 4 . The external voltage V APP  is applied from the voltage source  50  through the second output of the central switch  46 , which includes A 2 , B 2  . . . N 2 . 
         [0070]    The switch controller  72  activates a selected switch  55 , one at a time, through the central switch  46  and applies the external voltage V APP  from the voltage source  50  to each of the solar panel  10  and inverter  31  pairs, serially. Since the duty cycle of each individual switch  55  is low—typically less than 2%—the switch controller  72  controls and drives a large number of switches  55 , solar panels  10 , and inverters  31 . 
         [0071]    There is no limitation on this embodiment that would preclude the switch controller  72  from switching and connecting the voltage source  50  to multiple solar panels  10  as long as the voltage applied to each panel is greater than the V min . In an alternative embodiment, more than one switch controller  72  can be added, with each switch controller  72  being responsible for a predetermined number of the solar panels  10 . Each of the switch controllers  72  can behave independently. 
         [0072]    As discussed above with reference to  FIG. 5 , the solar cell management system  300  can also apply the external voltage V App  to the photovoltaic device  200  using the voltage pulser  60  for a number of configurations of the solar panels  10 . Turning to  FIG. 13 , the voltage pulser circuit  60  is connected to the solar panels  10  wired in series. As was discussed above, as long as the inequality in Equation 1 is satisfied, the voltage pulser  60  behaves as shown in  FIG. 14 .  FIG. 14  illustrates the external voltage V App  relative to the voltage across each successive solar panel  10  (measured across the node A to each of the solar panels  10  at the nodes B, C . . . N) in the series. As shown in  FIG. 14 , the voltage at each solar panel  10  increases by the voltage output of the solar panel  10 . For example, each solar panel  10  generates a voltage of approximately twenty-four volts and that a voltage measured across any solar panel  10  (from the node A to the node B, C . . . N) is approximately k×24 Volts, where k is the number of solar panels  10  across which the voltage is being measured. If the inequality of the Equation 1 cannot be satisfied, the embodiment shown in  FIG. 13  can be modified to include additional voltage pulsers  60 . 
         [0073]    With reference to  FIG. 5 , to maximize the strength of the electric field  250  across the set of solar cells  100  or the solar panels  10 , the solar management system  300  considers the DC voltage being generated by each of the solar cells  100  or the solar panels  10  themselves. In one embodiment, a high voltage uplift circuit, such as an Uplift Injector Circuit  90  (shown in FIG.  18 ), can be used with the voltage pulser  60  to superimpose a voltage pulse on top of the DC voltage of the solar panels  10  themselves. This superposition of the voltage pulse from the voltage pulser  60  on top of the DC voltage generated by solar panels  10  can be done by creating a negative reference for the injected high voltage pulse signal that is equal to the positive DC voltage delivered by solar panels  10 . 
         [0074]    Turning to  FIG. 18 , the Uplift Injector Circuit  90  includes a capacitor  91 , working in concert with an inductor  92 , allows the capacitor  91  to hold a charge equal to the voltage delivered by the solar panels  10 . The capacitor  91  and the inductor  92  creates an uplifted negative reference for the injected high voltage pulse signal which is connected to the voltage pulser  60  through capacitors  94  and  95 . The positive reference from the voltage pulser  60  is connected through a diode  93 , which provides reverse bias protection to the positive voltage line connected to the interface that connects to the solar panels  10  and the interface which is connected to the inverter  31 . To provide RF isolation so that voltage pulses from the voltage pulser  60  are not shorted out by the inverter  31  and to additionally provide RF isolation between the other solar panels  10  connected between the Uplift Injector Circuit  90   90  and the inverter  31 , inductors  96  and  97  can be placed in series between the inverter  31  and the voltage pulser  60  to provide a RF choke for any high voltage pulses. The inductors  96  and  97  attenuate any voltage pulse from the voltage pulser  60  passing across them and isolate the voltage pulser  60  from the remainder of the circuit towards the inverter  31 . 
         [0075]    As shown in  FIG. 18 , the inductor  92  provides high reactance protection to the injected high voltage pulse signal, keeping the signal from feeding back into the capacitor  91 . The result is the injected high voltage pulse signal sitting on top of the DC voltage delivered by the solar panels  10  and rising and falling with the DC voltage, thereby maximizing the voltage pulse. 
         [0076]    In a preferred embodiment, the Uplift Injector Circuit  90  can be incorporated as part of an interface between each voltage pulser  60  and a number of solar panels  10 . 
         [0077]    In some embodiments, more than one voltage pulser  60  can be used for a predetermined number of solar panels  10  as shown in  FIG. 15A . Turning to  FIG. 15A , the solar panels  10  are arranged in both in series and in parallel and interconnected with the voltage pulsers  60 . Each voltage pulser  60  is responsible for k panels and interconnected to the inverter  31 . In some embodiments, similar to the switching system previously described in  FIGS. 6 and 8-11 , the use of more than one voltage pulser  60  can be synchronized. However, in the embodiment shown in  FIG. 15A , the use of more than one voltage pulser  60  advantageously does not require synchronization between different voltage pulsers  60 . Because the voltage pulse from each voltage pulser  60  is local to a set of the solar panels  10  that are interconnected, the application of the voltage pulse does not affect the output of the inverter  31 . 
         [0078]    Another embodiment of implementing multiple voltage pulsers for the solar panels  10  wired in series is shown in  FIG. 15B . Turning to  FIG. 15B , the voltage pulser  60  is connected to each solar panel  10  via a serial switch  70 . The serial switch  70  can include N output ports for coupling k solar panels  10  as shown in  FIG. 15B . In the embodiment shown in  FIG. 15B , to simplify the figures and for illustration purposes only, interconnections between different points in the circuit are designated by the capital letters A 1  and B 1  with A 1  connecting to A 1  and B 1  connecting to B 1  and so on. 
         [0079]    The serial switch  70  includes one input port connected to the voltage pulser  60 . The N output ports of the serial switch  70  connect the voltage pulser  60  across k panels  10  at a time. In one example, the serial switch  70  connects the voltage pulser  60  to the output ports A 1  and A 2 . The voltage pulser  60  applies the external voltage V App  across the solar panels  1  through k. The serial switch  70  disconnects the voltage pulser  60  from the outputs A 1  and A 2  and connects the voltage pulser  60  to outputs B 1  and B 2 . When activated, the voltage pulser  60  applies the voltage pulse V App  across the k panels in that leg of the solar panels  10  wired in series. In a similar manner, the serial switch  70  cycles through all ports applying the voltage pulse V App  to k panels at a time. After all of the n solar panels  10  in series have had a voltage pulse V App  applied, the serial switch  70  reconnects to leads A 1  and A 2  and the process repeats. In this manner, a single voltage pulser  60  can be utilized to apply voltage pulses V App  to a large number of solar panels  10 . Because the duty cycle of the voltage pulse is low—typically less than 2%—a single voltage pulser  60  can control multiple solar panels  10 . 
         [0080]    Turning to  FIG. 16 , the voltage pulser  60  cooperates with the solar panels  10  wired in both series and parallel in the manner discussed above with reference to  FIG. 2C . The voltage pulser  60  is connected across the  2   k  solar panels  10  and the inverter  31 . For most situations, the magnitude of the series and shunt resistances (&gt;&gt;1 MΩ) found in most solar panels  10  allow the voltage pulser  60  to cooperate with a large number of solar panels  10 . 
         [0081]      FIGS. 17A and 17B  illustrates the voltage pulser  60  cooperating with the typical, residential installations of a solar panel  10 . In one embodiment, turning to  FIG. 17A , the voltage pulser  60  is integrated into the inverter  31  connected across solar panel  10 . 
         [0082]      FIG. 17B  illustrates an alternate embodiment for cooperating with the typical, residential installations of a solar panel  10  and includes each solar panel  10  and the inverter  31  connected via the serial switch  70  to a central voltage pulser  60 . The central voltage pulser  60  applies the voltage pulse V App  through the serial switch  70  and serially to each of the solar panels  10 . The serial switch  70  in  FIG. 17 b    is shown as an Nx 1  switch. The serial switch  70  has one input port, which is connected to the voltage pulser  60 , and N output ports, which are connected across each individual solar panel  10  as shown in  FIG. 17 b   . The serial switch  70  connects voltage pulser  60  across each panel  10  one at a time. 
         [0083]    In one example, the serial switch  70  connects the voltage pulser  60  to the output ports A 1  and A 2 . When activated, the voltage pulser  60  applies the voltage pulse V App  across a selected solar panel  10  coupled to the serial switch  70 . The serial switch  70  then disconnects the voltage pulser  60  from the output ports A 1  and A 2  and connects the voltage pulser  60  to the output ports B 1  and B 2 . Again, when activated, the voltage pulser  60  applies the voltage pulse V App  across another selected solar panel  10  coupled to the serial switch  70 . In a like manner, the serial switch  70  cycles through all active ports applying a voltage pulse V App  to a selected solar panel  10  at a time. After all of the n solar panels  10  have had a voltage pulse V App  applied, the serial switch  70  reconnects to the output ports Al and A 2 , and the process repeats. In this manner, a single voltage pulser  60  can be utilized to apply voltage pulses V App  to a large number of solar panels  10 . Since the duty cycle of the voltage pulses is very low, typically less than 2%, a single voltage pulser  60  can control a large number of the solar panels  10  and inverters  31 . 
         [0084]    There is no limitation on this embodiment that would preclude the central high voltage pulse generator from switching a voltage pulse to multiple solar panels concurrently as long as the voltage applied to each panel is greater than V min . While the option exists to apply a high voltage pulse switch to multiple solar panels  10  concurrently, the preferred embodiment includes a single voltage pulser  60  for switching between the solar panels  10 , such as in serial. In the event that the number of the solar panels  10  becomes large, additional voltage pulsers  60  and serial switches  70  can be added, with each voltage pulser  60  responsible for a number of solar panels  10 . 
         [0085]    The described embodiments are susceptible to various modifications and alternative forms, and specific examples thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the described embodiments are not to be limited to the particular forms or methods disclosed, but to the contrary, the present disclosure is to cover all modifications, equivalents, and alternatives.