Power conversion device with controller auxiliary power

A system comprising:

• a first photovoltaic (PV) power source and a second PV power source;
• a power device configured to convert a first input power from the first PV power source and a second input power from the second PV power source to a combined output power at a power device output, wherein the power device includes:
• a first power stage including a first pair of input terminals electrically connected to the first PV power source, a first pair of output terminals, and a first power converter electrically connected between the first pair of input terminals and the first pair of output terminals;
• and
• a second power stage including a second pair of input terminals electrically connected to the second PV power source, a second pair of output terminals, and a second power converter electrically connected between the second pair of input terminals and the second pair of output terminals, wherein the first pair of output terminals and the second pair of output terminals are connected in parallel to the power device output;
• at least one controller configured to use auxiliary power derived from the first and the second PV power sources, with at least one of the first and the second PV power sources being above a threshold operating voltage, and use the auxiliary power to:
• perform a PV operating point search of the first PV power source to detect a peak PV operating point below the threshold operating voltage of the at least one controller, and
• control, after the PV operating point search, the first power stage to convert the first input power, at the peak PV operating point below the threshold operating voltage, to part of the combined output power.

A method comprising:

• converting, by a first power stage, a first input power received from a first photovoltaic (PV) power source via a first pair of input terminals of the first power stage;
• converting, by a second power stage, a second input power received from a second PV power source via a second pair of input terminals of the second power stage, wherein a first pair of output terminals of the first power stage and a second pair of output terminals of the second power stage are connected in parallel to a power device output;
• generating, at the power device output, a combined output power by combining the converted first input power and the converted second input power;
• performing, by at least one controller using auxiliary power derived from the first or the second PV power sources, a PV operating point search of the first PV power source in a range below a threshold operating voltage of the at least one controller, wherein the second PV power sources is above the threshold operating voltage during the PV operating point search;
• and
• controlling, by the at least one controller using the auxiliary power and after the PV operating point search, the first power stage to convert the first input power at the PV operating point below the threshold operating voltage to the converted first input power that is combined into the combined output power.