Tunable Capacitor Based on Polymer-Dispersed Liquid Crystal for Optimum Micro-Power Harvesting

Author

Chung, S.-Y. ; Chen, Y.-Y. ; Wu, W.J. ; Shih, W.-P. ; Chang, P.-Z.

Author_Institution

Nat. Taiwan Univ., Taipei

fYear

2007

fDate

10-14 June 2007

Firstpage

137

Lastpage

140

Abstract

This paper presents a tunable power harvesting device and explains how a tunable capacitor based on polymer-dispersed liquid crystal (PDLC) can be used to optimize the power harvesting efficiency. For improving the power harvesting efficiency, we have developed a PDLC tunable capacitor to adjust the resonance frequency of the piezoelectric micro-cantilever beam to match the frequency of environmental random vibration in real time. Fabrication process and measurement results of the PDLC tunable capacitor are detailed. Large tuning ratio up to 117.5% of the PDLC tunable capacitor is measured at 75 kHz signal frequency. At 12 V driving voltage, tuning ratio as 55% can be achieved.

Keywords

capacitors; liquid crystals; piezoelectric devices; environmental random vibration; fabrication process; optimum micropower harvesting; piezoelectric microcantilever beam; polymer-dispersed liquid crystal; tunable capacitor; Capacitors; Equivalent circuits; Liquid crystal devices; Liquid crystal polymers; Power engineering and energy; Resonance; Resonant frequency; Tunable circuits and devices; Tuning; Vibrations; Tunable capacitor; polymer-dispersed liquid crystal; power harvesting;

fLanguage

English

Publisher

ieee

Conference_Titel

Solid-State Sensors, Actuators and Microsystems Conference, 2007. TRANSDUCERS 2007. International

Conference_Location

Lyon

Print_ISBN

1-4244-0842-3

Electronic_ISBN

1-4244-0842-3

Type

conf

DOI

10.1109/SENSOR.2007.4300090

Filename

4300090