Self-powered wireless sensing system with cylindrical high voltage side electric field energy harvesting by discharge circuit

To warn of overcurrent heating, temperature wireless sensor node (WSN) need to be deployed on the overhead lines of the power grid. The sustainable power supply of WSN is difficult. Using the electric field energy around the transmission line to power the sensor has the advantages of stability, reliability and sustainability, but the electric field energy harvesting (EFEH) power need to be improved. This paper studies the principle of energy harvesting by displacement current and discharge method, and analyzes the influencing factors of the output power of the EFEH unit. The power improvement method of the EFEH unit is proposed by improving the coupling capacitor and the energy storage capacity discharge voltage. The relationship between the structural parameters of energy cylinder and induced potential and coupling capacitance is explored by COMSOL simulation software. A low-cost, self-driven and adjustable high voltage undervoltage lock (UVLO) circuit is proposed. A 10 kV high voltage generation platform is built in the laboratory, and the wireless temperature and humidity sensor is self-powered by the EFEH with power of 2.04 mW. This research has important theoretical and application value for the high voltage side EFEH powered WSN.