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A photovoltaic (PV) energy system includes a pulsed bus defined by a non-zero average value voltage that is proportional to a rectified utility grid AC supply voltage. The PV energy system also includes a plurality of PV modules, each PV module including a bucking circuit configured to convert a cor

A photovoltaic (PV) energy system includes a pulsed bus defined by a non-zero average value voltage that is proportional to a rectified utility grid AC supply voltage. The PV energy system also includes a plurality of PV modules, each PV module including a bucking circuit configured to convert a corresponding PV voltage into a pulsing current, wherein the pulsating bus is configured to sum the pulsing currents produced via the plurality of PV modules such that a resultant pulsing current is injected into the pulsating bus in phase with the non-zero average value voltage. A current unfolding circuit is configured to control the amount of AC current injected into the utility grid in response to the resultant pulsing current.

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1. A photovoltaic (PV) energy system, the PV energy system comprising: a pulsating bus defined by a non-zero average value voltage that is proportional to a rectified utility grid AC supply voltage;a plurality of PV modules, each PV module comprising a stiffening capacitor and a PV generator with a

1. A photovoltaic (PV) energy system, the PV energy system comprising: a pulsating bus defined by a non-zero average value voltage that is proportional to a rectified utility grid AC supply voltage;a plurality of PV modules, each PV module comprising a stiffening capacitor and a PV generator with a corresponding voltage to current converter configured together to convert a PV voltage into a pulsing current that is injected into the pulsating bus, wherein each PV module is directly connected to the pulsating bus, and further wherein each voltage to current converter consists solely of a buck converter, or solely of a boost converter, or solely of an isolated converter, or solely of a boost converter with flyback capability, and further wherein each PV module is coupled to a corresponding voltage to current converter via a corresponding stiffening capacitor; anda current unfolding circuit configured to control the polarity of AC current injected into the utility grid in response to the injected pulsing currents such that power generated by the plurality of PV modules is transferred to the utility grid, wherein the current unfolding circuit is directly connected to the pulsating bus, and further wherein the current unfolding circuit is coupled to each PV module stiffening capacitor via the corresponding PV module voltage to current converters. 2. The PV energy system according to claim 1, wherein the pulsing current is defined by a haver-sine waveform that is proportional to an absolute value of a utility grid AC voltage in response to an AC utility grid voltage that is not purely sinusoidal and whose amplitude is defined by the available power from at least one PV generator and the amplitude of AC voltage. 3. The PV energy system according to claim 1, wherein the pulsing current is proportional to an absolute of a utility grid AC voltage in response to a utility grid voltage that is non-sinusoidal and whose amplitude is defined by the available power from at least one PV generator and the amplitude of AC voltage. 4. The PV energy system according to claim 1, wherein the pulsing current is proportional to the pulsating bus voltage in response to a non-sinusoidal utility grid voltage and whose amplitude is defined by the available power from at least one PV generator and the amplitude of AC voltage. 5. The PV energy system according to claim 1, wherein the pulsing current is proportional to a filtered version of the pulsating bus voltage in response to a non-sinusoidal utility grid voltage and whose amplitude is defined by the available power from at least one PV generator and the amplitude of AC voltage. 6. The PV energy system according to claim 1, wherein the pulsing current comprises a fundamental component that is proportional to a fundamental component of the utility grid voltage waveform and whose amplitude is defined by the available power from at least one PV generator and the amplitude of AC voltage. 7. The PV energy system according to claim 1, wherein the pulsing current is proportional to an absolute value of a filtered version of the utility grid voltage in response to a non-sinusoidal utility grid voltage and whose amplitude is defined by the available power from at least one PV generator and the amplitude of the utility voltage. 8. The PV energy system according to claim 7, wherein the non-sinusoidal utility grid voltage comprises a representation of the utility grid voltage based on the pulsating bus voltage. 9. The PV energy system according to claim 1, wherein each converter is configured to be controlled via a simple and readily available off the shelf power factor regulator IC. 10. The PV energy system according to claim 1, wherein at least one PV module is operationally connected to the pulsating voltage bus. 11. The PV energy system according to claim 1, wherein each converter can be sub divided for each PV cell of the corresponding PV generator or clusters of cells of the corresponding PV generator. 12. The PV energy system according to claim 11, wherein each converter comprises a bucking or boosting circuit including a buck or anti-parallel diode configured to also function as a bypass diode configured to protect at least one PV cell or PV cell cluster to which it is connected from exposure to excessive voltage during shading from the remaining PV cells in the generator. 13. The PV energy system according to claim 12, wherein the bypass diode is further configured to ensure its corresponding PV module remains operational during a bucking or boosting circuit switch failure caused by a short, open or partial switch failure. 14. The PV energy system according to claim 1, wherein each PV module is configured to operate only when the current unfolding circuit is connected to its corresponding converter. 15. The PV energy system according to claim 1, wherein the current unfolding circuit is further configured to generate the non-zero average value voltage in response to the main utility grid supply voltage. 16. The PV energy system according to claim 1, wherein each converter comprises a voltage boosting circuit configured to allow the PV energy system to operate at its maximum power point, regardless of whether the corresponding PV module is subjected to shading or other factors that can limit the voltage. 17. The PV energy system according to claim 1, wherein each PV module cannot produce an output voltage or an output current until the current unfolding circuit presents a voltage to the pulsating bus. 18. The PV energy system according to claim 1, wherein each PV module and the current unfolding circuit together are configured to provide compatibility with traditional PV inverters if the pulsating bus becomes DC. 19. The PV energy system according to claim 1, wherein the plurality of PV modules is configured to provide constant power suitable for use with three-phase PV energy systems. 20. The PV energy system according to claim 1, wherein at least one PV module is configured with a different power rating than at least one other PV module while retaining interchangeability of PV modules in the absence of PV energy system modifications to accommodate the interchangeability of the PV modules such that the PV energy system maximizes available roof space used to attach the PV energy system. 21. The PV energy system according to claim 1, wherein the plurality of PV modules are configured to provide a plurality of PV arrays having dissimilar directional orientations such that the PV energy system provides increased sun tracking capability and energy harvesting capability beyond that achievable with a conventional PV energy system having all PV modules oriented in the same direction.