Passive MEMS DC Electric Current Sensors

Abstract

In this chapter, DC current sensors applicable to two-wire appliances are presented. Firstly, background information of current sensors is presented showing the properties of different current measurement applications. Working principles of passive and actuating cantilever-based current sensors are then demonstrated theoretically, and the expressions of magnetic force and piezoelectric outputs are derived. Specifically, the design of partitioning piezoelectric thin film from one plate to n plates in series is discussed. Following are structural design and prototype fabrication process. With the achieved prototypes, two types of current measurements are carried respectively for verification and demonstration of the working principles. Finally, a conclusion is drawn and perspective of cantileverbased current sensors is given.