上海科技大学知识管理系统

In piezoelectric energy harvesting (PEH), utilizing the synchronized switch interface circuit can significantly enhance the energy harvesting capability. Vibration sensing is necessary for carrying out the synchronized switch actions. The peak detection was usually implemented with an external displacement sensor in the early designs, which was not compatible with self-contained and integrated applications. This article proposes a compact self-sensing synchronized switch interface for PEH by using a modified buck-boost topology and implementing a time-sharing control on it. The interface circuit works in strong discontinuous conduction mode. The sensing function is realized by extracting a tiny amount of charge from the piezoelectric transducer, which introduces little influence to the piezoelectric source. While the energy harvesting function is realized by extracting charge at a higher intensity. The two functions cooperate in a time-sharing way. The sensed full-cycle information is used to identify the voltage peaks, at which the switch actions are synchronously carried out. The self-sensing mechanism is studied theoretically and experimentally. In the experiments, the self-sensed information of the piezoelectric voltage matches the measured result. The peak detection is well performed. The newly proposed self-sensing mechanism offers a more informative and flexible solution for the designs of synchronized switch interface circuits. © 1982-2012 IEEE.