Patent ID: 8227683

Claim:
A photovoltaic system, comprising: a photovoltaic source of electrical energy, the photovoltaic source comprising power-generating characteristics defined by a family of source voltage-current curves comprising points of maximum electrical power over a respective range of at least one of the following for the photovoltaic source: distinct illumination intensities and distinct temperatures; a resistive divider network for sensing voltage from the photovoltaic source; a gain amplifier for receiving the sensed voltage from the resistive divider network and amplifying the sensed voltage from the resistive divider network; a switching converter coupled to the photovoltaic source and comprising an input voltage-current curve having a predefined functional relationship between an input voltage and an input current configured to provide a cubic fit approximation with respect to at least some of the points of maximum electrical power for the photovoltaic source, the switching converter further comprising at least one switch and a pulse width modulator for receiving the amplified sensed voltage from the gain amplifier to establish a directly proportional relationship between a duty cycle of the switching converter and the voltage from the photovoltaic source and for supplying gating signals to the at least one switch for operating the switching converter in a discontinuous conduction mode to establish a relationship between the input current of the switching converter, the input voltage of the switching converter, and a square of the duty cycle of the switching converter that is the cubic fit approximation of at least some of the points of maximum electrical power on the source voltage-current curves without having to perform current and voltage calculations corresponding to a maximum power from the photovoltaic source.