Abstract

For battery powered outdoor equipment, such as video doorbell, to increase the battery working time and easy to install anywhere, sometimes the photovoltaic (PV) panel is used as an auxiliary power supply to charge the battery. Photovoltaic cells are one of the most important parts in PV panel, the output power and output voltage of PV cells varies with sunlight intensity, so a MPPT (maximum power point tracking) method is used to maximize the output energy of PV cells.

To achieve MPPT, it means that the power converter needs to automatically operate within a specific supply voltage range, which is often different from converter default startup and shutdown voltage, so it is hard to find an usual power converter that can be used to different types of PV panel.

This application note introduces a simple hysteresis control method which can provide a flexible design to achieve MPPT with generic DC/DC converter, regardless of the different maximum power point. Take TI's Boost converter TPS61023 as an example, the detailed operation scheme and test results are also given in this documentation.