Distributed power harvesting systems using DC power sources

摘要

A system and method for combining power from DC power sources. Each power source is coupled to a converter. Each converter converts input power to output power by monitoring and maintaining the input power at a maximum power point. Substantially all input power is converted to the output power, and the controlling is performed by allowing output voltage of the converter to vary. The converters are coupled in series. An inverter is connected in parallel with the series connection of the converters and inverts a DC input to the inverter from the converters into an AC output. The inverter maintains the voltage at the inverter input at a desirable voltage by varying the amount of the series current drawn from the converters. The series current and the output power of the converters, determine the output voltage at each converter.

主权项

1. A system comprising:
a plurality of direct current (DC) power sources; a plurality of DC/DC power converters, each comprising: output terminals,
input terminals coupled to a respective DC power source of the plurality of DC power sources,a controller configured to set an input voltage and an input current at the input terminals to maximize power of the respective one of the DC power sources, anda power conversion circuit configured to convert an input power received at the input terminals to an output power at the output terminals, the output terminals of all the DC/DC power converters coupled in series to form a series string; and a power inverter comprising DC terminals and alternating current (AC) terminals, wherein the DC terminals of the power inverter are coupled to the series string, wherein the power inverter is configured to convert DC power received from the series string to AC power at the AC terminals, and wherein the power inverter includes circuitry with an inverter control loop configured to take a measurement of an inverter input voltage at the DC terminals and maintain the inverter input voltage at a regulated level based on the measurement.