Driving and Position Sensing Algorithm for an Electrostatic Actuator Using Pulse-width Modulation

펄스폭 변조를 이용한 정전형 액추에이터의 구동 및 위치 검출 알고리즘

  • 민동기 (삼성종합기술원 Semiconductor Device Lab.) ;
  • 전종업 (울산대학교 기계자동차공학부)
  • Published : 2008.06.15

Abstract

Capacitive position sensing with modulation technique is widely used in electrostatic actuator applications. To maximize the electrostatic force and the position-sensing gain, capacitors for driving and capacitors for sensing are shared, i.e, after applying the driving voltage with high-frequency modulating signals using op amps, the position is demodulated from the modulated signal. In high-voltage applications, however, low bandwidth of a high-voltage op amp hinders adding the high-frequency modulating signal to the driving voltage. In this paper, new and very simple driving and sensing method is proposed, in which the pulse-width modulated driving voltage eliminates the need of the high-frequency modulating signal for position sensing. This new algorithm is proved by the simulation results using Matlab/SIMULINK.

Keywords

References

  1. Fan, L. S., Hirano, T., Hong, J., Webb, P. R., Juan, W. H., Lee, W. Y., Chan, S., Semba, T., Imaino, W., Pan, T. S., Pattanaik, S., Lee, F. C., McFadyen, I., Arya, S., and Wood, R., 1999, "Electrostatic Microactuator and Design Considerations for HDD Applications," IEEE Trans. on Magnetics, Vol. 35, No. 2, pp. 1000-1005 https://doi.org/10.1109/20.753823
  2. Jono, K., Hashimoto, M., and Esashi, M., 1994, "Electrostatic Servo System for Multi-axis Accelerometers," Proc. IEEE Workshop on Micro Electro Mechanical Systems, Oiso, pp. 251-256
  3. Lotters, J. C., Olthuis, W., Veltink, P. H., and Bergveld, P., 1999, "A Sensitive Differential Capacitance to Voltage Converter for Sensor Applications," IEEE Trans. on Instrumentation and Measurement, Vol. 48, No. 1, pp. 89-96 https://doi.org/10.1109/19.755066
  4. The MathWorks, Inc., viewed 5 May 2008,