Optimised energy management for energy harvesting powered wireless sensors

Energy harvesting provides a promising opportunity as the power source for wireless sensors for the Internet of Things (IoT) related applications (e.g. smart buildings, autonomous cars). However there are issues encountered when using energy harvesters as the sole power source which include limited efficiency as well as the low-power and low-voltage nature of the energy harvesters. The main reason for the limited efficiency is due to the low-power, low-voltage nature of suitable energy harvesters for the wireless sensors required for automation and IoT based applications. This thesis aims to increase the efficiency of energy harvesting powered sensors therefore furthering the suitability of energy harvesters as a power source. A new optimised switched supercapacitor energy management circuit is proposed, which overcomes many of the issues encountered by existing circuits. In particular the circuit increases the system efficiency as well as delivering suitable pulses of power to wireless sensors. The circuit performance is demonstrated for a range of typical energy harvesting powered systems with particular focus on indoor solar harvesting, however the concept can be applied to range of sources and sensors