Aircraft Self-powered Wireless Sensors Based On Multiple Environmental Energy Harvest

The working environment of aircraft is advers and complex. It will seriously threaten the flight safety without test and control of the aircraft working condition. Distributed wireless sensor network using battery is commonly used in the on-line test of structures. But battery can't supply the sensor node for a long time. The problem of power supply has become the main bottleneck of the development of wireless sensor network. And energy supply technology has become one of the core issues of the technology.Firstly, the typical environment of aircraft is investigated to get the distribution and characteristics of the vibration and thermal Energy. Then the thermal and vibration conversion scheme is determined, and its output characteristics is analyzed. Based on the research, the maximum power point tracking scheme for thermoelectric generator is proposed. The scheme uses pulse width modulation controls the Buck-Boost convertor which can provide a virtual impedance of no power consumption. The virtual impedance can help to achieve maximum power tracking. A power measurement scheme is proposed for low power wireless nodes. The output voltage of the piezoelectric material is much lower than thermoelectric material. A step-up scheme based on the method of synchronous charge extraction is proposed. A analog switch is used to reduce power consumption. At the same time, the output power of the piezoelectric material is not affected.A multiple energy storage regulator module is designed to ensure the super capacitor can store energy in all conditions. Then, a start circuit is designed to start the microcontroller. It will be shut down after the efficient channel is on. Finally, a wireless sensor prototype is made and tested. Experiment results show that the scheme proposed in this paper can improve the energy harvesting efficiency and the output electric power greatly. And can realize the stable power supply under laboratory conditions.