A photovoltaic panel with multiple photovoltaic sub-strings including serially-connected photovoltaic cells and having
direct current (DC) outputs adapted for
interconnection in parallel into a parallel-connected DC power source. A
direct current (DC) power converter including input terminals and output terminals is adapted for
coupling to the parallel-connected DC power source and for converting an input power received at the input terminals to an output power at the output terminals. The
direct current (DC) power converter optionally has a control loop configured to set the input power received at the input terminals according to a previously determined criterion. The control loop may be adapted to receive a feedback
signal from the input terminals for maximizing the input power. A bypass
diode is typically connected in shunt across the input terminals of the converter. The bypass
diode functions by passing current during a failure of any of the sub-strings and / or a partial shading of the sub-strings. The bypass
diode may be a single bypass diode connected across the parallel-connected DC power source. The DC power converter may convert the input power at
high current to the output power at a lower current. The output terminals may be connectible with wire cables to a load, and the DC power converter is configured to reduce
energy loss through the wire cables to the load.