System and method for increasing voltage in a photovoltaic inverter

摘要

A system and method for controlling the DC voltage provided to a PV inverter is disclosed. A PV system includes a pair of PV array group configured to generate a direct current (DC) output from received solar irradiation and a DC-to-AC power inverter electrically coupled to the pair of PV array groups to receive the DC output therefrom and invert the DC output to an AC output. The PV system also includes a switching element positioned between the pair of PV array groups and the DC-to-AC power inverter, with the switching element being configured to selectively connect the pair of PV array groups to the DC-to-AC power inverter in one of a series arrangement and a parallel arrangement, so as to control a level of DC voltage received by the DC-to-AC power inverter from the pair of PV array groups.

主权项

1. A photovoltaic (PV) system comprising:
a pair of PV array groups configured to generate a direct current (DC) output from received solar irradiation, the pair of PV array groups comprising a first PV array group and a second PV array group; a DC-to-AC power inverter electrically coupled to the pair of PV array groups to receive the DC output therefrom, the DC-to-AC power inverter configured to invert the DC output to an AC output; a switching element positioned between the pair of PV array groups and the DC-to-AC power inverter, the switching element being configured to selectively connect the pair of PV array groups to the DC-to-AC power inverter in one of a series arrangement and a parallel arrangement, so as to control a level of DC voltage received by the DC-to-AC power inverter from the pair of PV array groups; and a controller configured to control switching of the switching element for connecting the pair of PV array groups to the DC-to-AC power inverter in one of the series arrangement and the parallel arrangement; wherein the controller is configured to operate the DC-to-AC power inverter within a pre-determined voltage operating window, between a minimum voltage value and a maximum voltage value; and wherein the controller is configured to:
measure the DC voltage output from the first and second PV array groups;compare the DC voltage output from the first and second PV array groups to the voltage operating window; andcontrol the switching element to connect the first and second PV array groups in one of the series arrangement and the parallel arrangement based on the comparison of the measured DC voltage output of the first and second PV array groups to the voltage operating window.