Piezoelectric transducers, which convert airflow induced vibrational energy into electrical energy, can be applied to self-powered supply and auxiliary power supply for various aircraft electronic systems. Micro-ringtone airflow piezoelectric generator, designed by the principle of airflow induced acoustic, is one kind among them. The vibrating piezoelectric generator, is usually mounted on the aircraft during the flight. The incoming airflow produces hydrodynamic acoustic source, which is the vibration source of the piezoelectric generator, actively vibrates the piezoelectric plate to convert energy. According to the vibration theory, a one-dimensional vibration model of piezoelectric generator with fixed peripheral pressure, under hydrodynamic excitation is established. The vibration and frequency characteristics of the piezoelectric transducers are analyzed by measuring the sound pressure and the piezoelectric generator voltage. Theoretical analysis and experimental results show that the frequency of hydrodynamic acoustic source is slightly lower than that of piezoelectric generator's natural frequency. Maximum output power is obtained when the inflow speed is in the range of 128 m/s-148 m/s, the corresponding hydrodynamic acoustic source frequency is 6.9 %-8.7 % lower than the natural frequency of the piezoelectric generator. Excitation force and the displacements of piezoelectric plate are in same frequency. But is ahead of phase angle than the displacement of piezoelectric plate.

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Abstract-The Wind Turbines is excited by natural wind in working environment. The piezoelectric generator gets concern 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. At rated voltage and power, stable frequency is the guarantee for system working accuracy. According to frequency pump principle, it is effective for piezoelectric transducer to increase gathering power through the adjustment of oscillator parameter and amplification of vibration frequency. The designed Airflow-induced Acoustic -vibration Piezoelectric Generator makes the frequency get close to the natural frequency of the piezoelectric transducer. The result shows that: the frequency of the sound pressure is stable, the vibration source frequency is amplified.