Ultra Low-Power Photovoltaic MPPT Technique for Indoor and Outdoor Wireless Sensor Nodes

Date Added: Dec 2010
Format: PDF

PhotoVoltaic (PV) energy harvesting is commonly used to power wireless sensor nodes. To optimise harvesting efficiency, Maximum Power Point Tracking (MPPT) techniques are often used. Recently-reported techniques focus solely on outdoor applications, being too power-hungry for use under indoor lighting. Additionally, some techniques have required light sensors (or pilot cells) to control their operating point. This paper describes an ultra low-power MPPT technique which is based on a novel system design and sample-and-hold arrangement, which enables MPPT across the range of light intensities found indoors and outdoors and is capable of cold-starting.