Enhanced magnetoelectric voltage in ferrite/PZT/ferrite composite for AC current sensor application

In this paper, we report the fabrication of a rare-earth free current sensor based on a PZT/NiCoZn-ferrite magnetoelectric (ME) trilayer composite disk. To improve the sensitivity of the sensor, the structure uses an in-plane series connection, which increases the ME voltage by two for a fixed volume. Then, we propose a full characterization of the sensor: electrical modeling, low and high frequency limits, sensitivity, linearity, distortion and resolution. The device is also evaluated under sinus, square, and triangle waveform currents, which are excitation signals commonly used in the field of electrical engineering. The current sensor shows high current sensitivity (90 mV/A), good linearity from 0.001 to 30 A and low added impedance (0.01 Omega) in a frequency range of 10 Hz-30 kHz for a very compact structure (4 cm(3)). It also exhibits a high resolution of 1 mA (for a 1 A peak signal) and good stability.