Thermal Energy Harvesting Wireless Sensor Node in Aluminum Core PCB Technology

This paper reports the design of a self-powered telemetric wireless sensor node for temperature measurement. The device is realized with a conventional off-the-shelf thermoelectric generator as a power source. It is sandwiched between two aluminum core printed circuit boards (PCBs). One board is exposed to the heat source and has the role of a heat collector, whereas another one with the mounted low profile heatsink acts as a heat spreader. Electronic components of the node are placed on the inner surfaces of the boards. Implemented step-up circuitry is accommodated to achieve stabile cold boot of the node at a low temperature difference between its hot side and ambient (less than 15 degrees C), even when it is in thermally inefficient position. Operational autonomy of the node in the absence of the heat source is extended by 30% comparing with the common step-up circuitry implementation. The aluminum core PCBs provide node simplicity and compactness, with small overall dimensions.