Condition of Transition in Airflow-Induced Acoustic Vibration Piezoelectric Generator Boundary Layer Inlet

摘要

The piezoelectric generator gets concerned in self-driven, self-powered, micro-electromechanical systems for its environmentally friendly feature, and easiness to get miniaturization. Power Quality is one of the necessary conditions for the normal operation of the generator system, while the output voltage and frequency are the main indicators to measure electrical energy. The piezoelectric vibration generator is single-phase AC generator, which was capacitive, whose core component are the exciting mechanism and piezoelectric transducers, the vibration source is excited by airflow, the piezoelectric transducer is an energy harvesting device by forced vibration, and the maximum convert power can be get when the frequency is equal to the natural frequency of the system. The fixed frequency of the common cantilever piezoelectric transducer structure is only a few dozens to a few hundred hertz. When the piezoelectric element was forced directly by the airflow, the impulse of aerodynamic force is irregular at rather low frequency. Also influence seriously the output power of the generator.