Research On Interface Circuit For Piezoelectric Vibration Energy Harvesting Based On Double Synchronized Switch Technique

With the development of the wireless sensing systems and low power electronic devices, theenergy harvesting technology has developed rapidly in recent years, and it has proved to be one of thekey technologies of wireless network sensor. This thesis is focused on the study of cantileverpiezoelectric vibration energy harvesting structures. A new optimized nonlinear energy harvestingtechnique was proposed. Using a self-powered scheme, this technique was turned into an efficient,independent and stable energy harvesting system.Firstly, the fundamental principle of piezoelectric material and the theoretical model of cantileverpiezoelectric power generator were described. Then the working principle of standard circuits, singlesynchronized switch harvesting inductor (SSHI) and double synchronized switch harvesting (DSSH)interface circuits were introduced. Based on the advantages of DSSH technique, an optimized schemefor the DC-DC converter of this circuit was proposed. This scheme overcame the difficulty of energyself-supply of DSSH technique. By the theoretical analysis in chapter three, the extracted power ofthis new technique can increase by300%compared with the maximal harvested power of the standardcircuit. The extracted power is also independent of the load resistance, which means that the extractedpower is a constant value in a wide range of load resistance.Secondly, this three circuits were simulated with the LTspice. The simulated results consistedwith the theoretical analysis results. The optimized DSSH technique was proved to be effective. Themodular hardware design was made for this optimized scheme, and it realizes functions of nonlinearenergy extraction, analog switch control and energy self-supply. Finally, the energy harvestingexperimental platform was set up. This three circuits were connected with piezoelectric materialsrespectively. The output power was tested under different load resistance. The experimental resultsalso consisted with the theoretical results.