Equivalent capacitor of polyvinylidene fluoride sensor and its influence on impact load measurement

As one of the main components of the polyvinylidene fluoride (PVDF) piezoelectric sensor, the equivalent capacitor of PVDF will influence the electrical signal output when subjected to the impact load, thus influencing the accuracy of its measurement. However, in previous research, the equivalent capacitor of PVDF and its possible influence on measurement results have usually been ignored. In this paper, by changing the external resistance, the influence of the equivalent capacitor of PVDF on its electrical signal output characteristics when subjected to impact load is studied. The results show that at this time, the charge generated by the PVDF will be partially concentrated on the equivalent capacitor, and the amount of concentration is determined by the impact load characteristics, external resistance and equivalent capacitance. Therefore, in some cases, it is unreasonable to ignore the equivalent capacitor in previous research, and this may lead to some errors and even get completely wrong results. Considering the charge concentrated on the equivalent capacitor can effectively avoid the problems of conventional methods, and reflect the applied impact load more accurately. In addition, to improve the accuracy of the measurement, on the basis of quantitative evaluation of the influence of the equivalent capacitor on electrical signal output, this paper puts forward a design method of the test circuit; that is, for different types of impact load and measurement accuracy requirements, PVDF with appropriate capacitance and reasonable external resistance should be selected. The research in this paper is helpful for the impact load measurement of PVDF and will improve the accuracy of the measurement to a certain extent.

Automated summary

This study investigates the influence of the equivalent capacitor of PVDF on its electrical signal output characteristics under impact load, emphasizing the importance of considering the equivalent capacitor to avoid errors in measurement results. The research findings highlight that the concentration of charge on the equivalent capacitor can accurately reflect the applied impact load.