System and method for managing the power output of a photovoltaic cell

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 an individual solar cell, an array of solar cells configured as a panel, or a group of solar panels. 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. Compared to conventional solar cells, these accelerated electron-hole pairs travel a shorter distance from creation (by incident optical radiation) and spend less time within the solar cell material, therefore the electron-hole pairs have a lower likelihood of recombining within the cells' semiconductor's material. This reduction in the electron-hole recombination rate results in an overall increase in the solar cells' efficiency and greater power output.

What is claimed is: 
     
         1 . A system for increasing photovoltaic device efficiency, comprising:
 a voltage source circuit; and   a switching circuit having a first port for coupling with said voltage source circuit and a second port for coupling with a photovoltaic device and being configured to alternate between a first mode for applying a voltage pulse with a positive magnitude to generate an electric field for increasing an output current or an output power produced by the photovoltaic device and a second mode for providing the increased output current or the increased output power to a load.   
     
     
         2 . The system of  claim 1 , wherein said voltage source circuit supplies a voltage signal to said switching circuit, and wherein said switching circuit applies the supplied voltage signal as the voltage pulse to generate the electric field. 
     
     
         3 . The system of  claim 2 , wherein the voltage signal comprises a direct current voltage signal, an alternating current voltage signal, a pulsed voltage signal, a periodic voltage signal or a combination thereof. 
     
     
         4 . The system of  claim 2 , wherein the voltage signal has an amplitude within an amplitude range between 100 Volts and 500 Volts, a frequency within a frequency range between 20 KHz and 200 KHz, a period within a period range between 5 microseconds and 50 microseconds, a nominal duty cycle in a duty cycle range between 0.1% and 10% or a combination thereof. 
     
     
         5 . The system of  claim 1 , wherein said switching circuit comprises at least one mechanical switch, at least one solid state switch, at least one switching transistor or a combination thereof. 
     
     
         6 . The system of  claim 1 , wherein said switching circuit is at least partially integrated with said voltage source circuit. 
     
     
         7 . The system of  claim 1 , wherein said switching circuit applies a plurality of voltage pulses to generate the electric field. 
     
     
         8 . The system of  claim 7 , wherein the voltage pulses have a uniform magnitude. 
     
     
         9 . The system of  claim 7 , wherein the voltage pulses comprise a plurality of sets of one or more voltage pulses. 
     
     
         10 . The system of  claim 9 , wherein said switching circuit applies a first set of one or more voltage pulses to generate a first electric field for increasing the output current or the output power produced by the photovoltaic device and subsequently applies a second set of one or more voltage pulses to generate a second electric field for increasing the output current or the output power produced by the photovoltaic device. 
     
     
         11 . The system of  claim 10 , wherein said switching circuit operates in the second mode between application of the first set of one or more voltage pulses and application of the second set of one or more voltage pulses. 
     
     
         12 . The system of  claim 7 , wherein said switching circuit operates in the second mode between application of adjacent sets of one or more voltage pulses. 
     
     
         13 . The system of  claim 1 , further comprising a control circuit for adjusting a frequency of the voltage pulse, a magnitude of the voltage pulse, a period of the voltage pulse, a repetition rate of the voltage pulse, a duty cycle of the voltage pulse, a duration of the voltage pulse or a combination thereof. 
     
     
         14 . The system of  claim 13 , wherein said control circuit adjusts the frequency of the voltage pulse to be within a frequency range between 20 KHz and 200 KHz, the magnitude of the voltage pulse to be within an amplitude range between 100 Volts and 500 Volts, the period of the voltage pulse to be within a period range between 5 microseconds and 50 microseconds, the duty cycle of the voltage pulse to be within a duty cycle range between 0.1% and 10%, the duration of the voltage pulse to be in a duration range between 10 nanoseconds and 2000 nanoseconds or a combination thereof. 
     
     
         15 . The system of  claim 13 , wherein said control circuit adjusts the frequency, the magnitude, the period, the repetition rate, the duty cycle, the duration or the combination thereof based at least in part on the output current of the photovoltaic device, an output voltage of the photovoltaic device or both. 
     
     
         16 . The system of  claim 13 , further comprising a measuring circuit for measuring the output current of the photovoltaic device, an output voltage of the photovoltaic device or both, wherein said control circuit adjusts the frequency, the magnitude, the period, the repetition rate, the duty cycle, the duration or the combination thereof based at least in part upon the measured output current, the measured output voltage or both. 
     
     
         17 . The system of  claim 16 , wherein said measuring circuit is at least partially integrated with said control circuit. 
     
     
         18 . The system of  claim 16 , wherein said measuring circuit includes a current sensor coupled in series between the photovoltaic device and the load for measuring the output current of the photovoltaic device, a voltage probe coupled across the photovoltaic device for measuring the output voltage of the photovoltaic device or a combination thereof. 
     
     
         19 . The system of  claim 13 , wherein said control circuit controls the electric field, the output current, the output power or a combination thereof by adjusting the voltage pulse. 
     
     
         20 . The system of  claim 19 , wherein said control circuit maximizes the output current of the photovoltaic device, the output power of the photovoltaic device or a combination thereof. 
     
     
         21 . The system of  claim 13 , wherein said control circuit is at least partially integrated with said voltage source circuit, said switching circuit or both. 
     
     
         22 . The system of  claim 1 , further comprising a control circuit for adjusting a switching frequency between the first mode and the second mode, a first duration of the first mode, a second duration of the second mode, a duty cycle of the first mode and the second mode, a first repetition rate of the first mode, a second repetition rate of the second mode or a combination thereof. 
     
     
         23 . The system of  claim 22 , wherein said control circuit adjusts the switching frequency to be within a frequency range between 20 KHz and 200 KHz, the first duration to be in a first duration range between 10 nanoseconds and 2000 nanoseconds, the second duration to be in a second duration range between 10 nanoseconds and 2000 nanoseconds, the duty cycle of the voltage pulse to be within a duty cycle range between 0.1% and 10% or a combination thereof. 
     
     
         24 . The system of  claim 22 , wherein said control circuit is at least partially integrated with said voltage source circuit, said switching circuit or both. 
     
     
         25 . The system of  claim 1 , wherein the second port of said switching circuit is coupled with a plurality of photovoltaic devices, said switching circuit being configured to alternate between the first mode for applying the voltage pulse with the positive magnitude to generate the electric field for increasing an output current or an output power produced by the plurality of photovoltaic devices and the second mode for providing the increased output current or the increased output power produced by the plurality of photovoltaic devices to the load. 
     
     
         26 . The system of  claim 25 , wherein the plurality of photovoltaic devices is disposed in a series device configuration, a parallel device configuration or a combination thereof. 
     
     
         27 . The system of  claim 1 , further comprising:
 a second voltage source circuit; and   a second switching circuit having a first port for coupling with said second voltage source circuit and a second port for coupling with a second photovoltaic device and being configured to alternate between a first mode for applying a voltage pulse with a positive magnitude to generate a second electric field for increasing an output current or an output power produced by the second photovoltaic device and a second mode for providing the increased output current or the increased output power produced by the second photovoltaic device to a second load.   
     
     
         28 . The system of  claim 27 , wherein the first mode of the second switching circuit is synchronized with the first mode of said switching circuit. 
     
     
         29 . The system of  claim 27 , wherein the second load is at least partially integrated with the load. 
     
     
         30 . The system of  claim 27 , wherein said second voltage source circuit is at least partially integrated with said voltage source circuit. 
     
     
         31 . The system of  claim 1 , further comprising an energy storage device for mitigating voltage drop-out at the load in the first mode of said switching circuit. 
     
     
         32 . The system of  claim 31 , wherein said energy storage device comprises a capacitor, an inductor, a battery or a combination thereof. 
     
     
         33 . The system of  claim 31 , wherein said energy storage device stores the output current or the output power produced by the photovoltaic device in the second mode of said switching circuit. 
     
     
         34 . The system of  claim 33 , wherein said energy storage device drives the load via the stored output power or the stored output current in the first mode of the switching circuit. 
     
     
         35 . The system of  claim 34 , further comprising a choke circuit for electrically isolating the load from the photovoltaic device in the radio frequency domain as said energy storage device drives the load. 
     
     
         36 . The system of  claim 35 , wherein said choke circuit comprises a capacitor, an inductor, a battery or a combination thereof. 
     
     
         37 . The system of  claim 1 , wherein said switching circuit operates in the second mode between adjacent first modes. 
     
     
         38 . The system of  claim 37 , wherein said switching circuit operates in the second mode for a predetermined time interval between the adjacent first modes. 
     
     
         39 . The system of  claim 38 , wherein said switching circuit operates to supply no voltage signal from said voltage source circuit during the predetermined time interval. 
     
     
         40 . The system of  claim 1 , wherein said switching circuit provides a current path between the photovoltaic device and the load in the second mode. 
     
     
         41 . The system of  claim 40 , wherein the photovoltaic device drives the load via the current path in the second mode. 
     
     
         42 . The system of  claim 1 , wherein said switching circuit provides a current path between said voltage source circuit and the photovoltaic device in the first mode. 
     
     
         43 . The system of  claim 42 , wherein the second port of said switching circuit is coupled with one or more existing electrodes of the photovoltaic device. 
     
     
         44 . The system of  claim 42 , wherein said switching circuit applies a voltage signal supplied by said voltage source circuit to the photovoltaic device via the current path in the first mode. 
     
     
         45 . The system of  claim 44 , wherein said switching circuit applies the voltage signal to the photovoltaic device without structural modification of the photovoltaic device. 
     
     
         46 . The system of  claim 42 , wherein said switching circuit breaks the current path between said voltage source circuit and the photovoltaic device in the second mode. 
     
     
         47 . The system of  claim 1 , wherein said switching circuit applies the voltage signal to generate the electric field across the photovoltaic device. 
     
     
         48 . The system of  claim 1 , wherein the load converts the output current or the output power produced by the photovoltaic device into alternating current power or current. 
     
     
         49 . The system of  claim 48 , wherein the load comprises an inverter. 
     
     
         50 . The system of  claim 48 , wherein the load is electrically isolated from the photovoltaic device in the radio frequency domain. 
     
     
         51 . The system of  claim 50 , wherein the load is electrically isolated from the photovoltaic device via a capacitor, an inductor, a battery or a combination thereof. 
     
     
         52 . The system of  claim 1 , wherein generation of the electric field increases the output current or the output power produced by the photovoltaic device by up to fifty percent under low light conditions. 
     
     
         53 . The system of  claim 1 , wherein generation of the electric field increases the output current or the output power produced by the photovoltaic device by more than fifty percent under low light conditions. 
     
     
         54 . The system of  claim 1 , wherein generation of the electric field increases the output current or the output power produced by the photovoltaic device by up to twenty percent under high intensity light conditions. 
     
     
         55 . The system of  claim 1 , wherein generation of the electric field increases the output current or the output power produced by the photovoltaic device between twenty percent and fifty percent. 
     
     
         56 . The system of  claim 1 , wherein generation of the electric field increases the output current or the output power produced by the photovoltaic device by more than fifty percent. 
     
     
         57 . The system of  claim 1 , wherein the increase in the output current or the output power produced by the photovoltaic device is based upon an intensity of light incident on the photovoltaic device, a thickness of the photovoltaic device, a pulse width of the voltage pulse, a frequency of the voltage pulse. 
     
     
         58 . The system of  claim 1 , wherein said switching circuit has a third port for coupling with the load and for providing the increased output current or the increased output power to the load in the second mode. 
     
     
         59 . The system of  claim 1 , wherein the second port of said switching circuit is configured for coupling with the load and for providing the increased output current or the increased output power to the load in both the first mode and the second mode. 
     
     
         60 . A method for increasing photovoltaic device efficiency, comprising:
 providing a voltage source circuit; and   coupling a first port of a switching circuit with the voltage source circuit, the switching circuit having a second port for coupling with a photovoltaic device and being configured to alternate between a first mode for applying a voltage pulse with a positive magnitude to generate an electric field for increasing an output current or an output power produced by the photovoltaic device and a second mode for providing the increased output current or the increased output power to a load.   
     
     
         61 . The method of  claim 60 , wherein the switching circuit has a third port for coupling with the load and for providing the increased output current or the increased output power to the load in the second mode. 
     
     
         62 . The method of  claim 60 , wherein the second port of the switching circuit is configured for coupling with the load and for providing the increased output current or the increased output power to the load in the first mode and in the second mode. 
     
     
         63 . A method for increasing photovoltaic device efficiency, comprising:
 coupling a first port of a switching circuit with a photovoltaic device, the switching circuit having a second port for coupling with a voltage source circuit and being configured to alternate between a first mode for applying a voltage pulse with a positive magnitude to generate an electric field for increasing an output current or an output power produced by the photovoltaic device and a second mode for providing the increased output current or the increased output power to a load.   
     
     
         64 . The method of  claim 63 , further comprising coupling a third port of the switching circuit with the load, the switching circuit being configured for providing the increased output current or the increased output power to the load via the third port in the second mode. 
     
     
         65 . The method of  claim 63 , further comprising coupling the first port with the load, the switching circuit being configured for providing the increased output current or the increased output power to the load via the first port in the first mode and in the second mode.