Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10409437 | Sensors and Actuators A: Physical | 2005 | 6 Pages |
Abstract
In this paper we study the potential use of a photovoltaic source as direct drive of electrostatic actuators, mainly for two reasons: first, because the I-V characteristic of a PV array has the shape of a current source limited in voltage and, second, because direct drive with galvanic isolation can be implemented at high voltages without using any dc/dc converter. We have used a standard PSpice model for a PV series array and a PSpice model of an electrostatic actuator. For sake of generality, the model for the PV array is the same one would like to use for the output circuit of a number of opto-couplers connected in series. Main parameters are: irradiance, I-V curve, and voltage, current and movement of the actuator (deflection) as a function of time. The number and surface of individual solar cells can be tailored to drive specific MEMS switches of high pull-in voltage value. As an example, a 14 cells-PV array, with a short circuit density current Isc = 1.2 nA, and open circuit voltage Voc = 8.7 V, would drive an electrostatic actuator having a pull-in voltage of 8.3 V, with three orders of magnitude lower kinetic energy than the equivalent voltage-drive. Both, this reduction in the kinetic energy at the impact, as well as the low hold-on voltage in the photovoltaic actuation reduce the electric field across the dielectric, which may lead to better reliability performance.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Sandra Bermejo, Luis Castañer,