Solar photovoltaic system with maximized ripple voltage on storage capacitor

摘要

We describe a photovoltaic (PV) power generation system comprising at least two PV panels and a power conditioning unit. The dc power outputs of the PV panels are connected in parallel to a dc power input of the power conditioning unit. The power conditioning unit comprises a dc-to-dc converter having an input coupled to the dc power input and an output coupled to a dc link of the unit, a dc-to-ac converter having an input coupled to the dc link and an ac mains power supply output, and an energy storage capacitor coupled to the dc link. The power conditioning unit is configured to perform maximum power point tracking (MPPT) responsive to a level of power flowing into the dc power input, and the level of power flowing into said dc power input is sensed at the dc link. In preferred implementations the energy storage capacitor is a non-electrolytic capacitor.

主权项

1. A method for generating a three phase ac mains power supply from a plurality of photovoltaic panels, the method comprising:
connecting dc power outputs from the plurality of photovoltaic panels in parallel to an input of a power conditioning unit; and converting an input flow of dc power from the dc power outputs into the three phase ac mains power supply using the power conditioning unit, wherein the converting comprises converting the input flow of dc power into an intermediate flow of dc power on a dc link of the power conditioning unit coupled to an energy storage capacitor having a ripple voltage that is proportional to the intermediate flow of dc power on the dc link, and converting the intermediate flow of dc power to the three phase ac mains power supply with a dc to ac converter that is controlled to maximize the ripple voltage on the energy storage capacitor.