A method for determining circuit model parameters of piezoelectric generator with low measurement cost

Abstract

The invention discloses a method for determining circuit model parameters of a piezoelectric generator with low measurement cost. One end of the piezoelectric generator is fixed on a vibration source,the other end is free, the constant sinusoidal vibration acceleration amplitude a is maintained, and the relationship curve between the output voltage of the piezoelectric generator and the vibrationfrequency under different load resistances RL is obtained by sweeping frequency. The short-circuit resonant frequency fsc, open-circuit resonant frequency foc, static capacitance Cmc, mechanical quality factor Qoc, mechanical quality factor QML, maximum power value Popt, and short-circuit resonant voltage VML (omega sc) are determined. The equivalent inductance Lm, the equivalent capacitance Cm,the equivalent resistance Rm, the equivalent input stress VF, the piezoelectric coupling coefficient A and the static capacitance Cmc are obtained. The invention can accurately describe the relationship between the output voltage characteristic of the piezoelectric generator and the load, the ambient vibration frequency and the acceleration, and the electric measuring instrument required for measuring is low in cost.

Description

technical field [0001] The invention relates to the fields of vibration environment energy collection technology and circuit design, and more specifically relates to a method for determining circuit model parameters of a piezoelectric generator with low measurement cost. Background technique [0002] Vibration generators can convert the vibration energy that exists widely in the environment into electrical energy. The energy conversion methods are divided into three types: electrostatic, electromagnetic and piezoelectric according to the principle of electromechanical conversion. The electrostatic type is realized by the capacity change of the variable capacitor due to vibration. The most attractive feature of this method is that it has IC compatibility, and it can be manufactured by silicon micro-processing technology and mass-produced. But in order to realize voltage constraint or charge constraint across the capacitor, independent power supply support is required. Electr...

AI Technical Summary

Problems solved by technology

Some existing circuit parameter extraction methods rely on measuring the vibration state of the piezoelectric generator to calculate and determine the parameters, and the required measuring instruments such as Doppler laser vibrometers are expensive

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