A method for extracting parameters of a piezoelectric multi-wafer equivalent circuit model

Abstract

A method for extracting parameters of a piezoelectric multi-wafer equivalent circuit model includes such steps as fixing one end of a piezoelectric multi-wafer on a vibration source, making the otherend free, keeping constant sinusoidal vibration acceleration amplitude a, and obtaining the relation curve between output voltage and vibration frequency of the piezoelectric multi-wafer under different load resistances RL through frequency sweeping. The short-circuit resonance frequency fsc, open-circuit resonance frequency foc, static capacitance Cmc, mechanical quality factor Qoc, maximum powervalue Popt and short-circuit resonance 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 multi-wafer and the load, the ambient vibration frequency and the acceleration, and the electric measuring instrument required for the measurement is low in cost.

Description

technical field [0001] The invention relates to the field of vibration environment energy collection technology and circuit design, and more specifically relates to a method for extracting parameters of a piezoelectric multi-chip equivalent circuit model. Background technique [0002] Vibration energy harvesting devices can convert the vibration energy widely present in the environment into electrical energy. The energy conversion methods are divided into three types: electrostatic, electromagnetic and piezoelectric according to the different electromechanical conversion principles. 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. Ele...

AI Technical Summary

Problems solved by technology

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

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