Appeal No. 1998-2460
Application No. 08/654,763
The invention is directed to a battery charger power
regulator that operates from a solar array and uses a Peak
Power Tracker (PPT). Unlike the prior art, which tracked and
determined the peak power point of the solar array, the
invention seeks to maximize the charge current of the battery
and not to operate at a particular point on the power curve of
the solar array. In particular, a PPT control loop is
utilized. This control loop employs an oscillator which, in
combination with other elements, causes an increase in the
duty cycle of a pulse width modulated buck regulator by
incrementally increasing the potential across a capacitor that
has no discharge path. The total output current from the buck
regulator is sensed and a decrease in current causes a
reduction in the duty cycle while the decreased duty cycle, in
turn, results in a sensed increase in total current. Thus,
the circuit will eventually oscillate about a maximum battery
charging current value that corresponds to the peak power
point of the solar array, analogous to the functioning of a
PPT.
-2-
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 Next
Last modified: November 3, 2007