Non‐invasive measurement of intensive power‐frequency electric field using a LiNbO3‐integrated optical waveguide sensor

Abstract

Abstract A LiNbO3‐integrated optical waveguide sensor with segmented shielding electrode are designed, fabricated and experimentally investigated. The segmented shielding electrode is designed to improve the sensor response at low frequency and simultaneously to have a larger half‐wave electric field. The minimum and maximum detectable power‐frequency electric fields of the sensor with 10 electrode elements in the time domain are 600 V/m and 139.8 kV/m, respectively, which results in a linear dynamic range of 47.3 dB. The minimum detectable electric field of the sensor with four electrode elements is 5.7 kV/m, while the maximum electric field that can be detected is more than 240 kV/m. By applying the 1.2/50 μs lightning electromagnetic pulse, the frequency response of the sensor is calculated from DC to 200 kHz with variations of less than ±2 dB. All these results investigate that such sensor has potential capability to become a portable instrument for the non‐invasive measurement of intensive power‐frequency electric field in high‐voltage power system.

Keywords

• Measurement of basic electric and magnetic variables
• Sensing and detecting devices
• Electrical instruments and techniques
• Optical instruments and techniques
• Optical waveguides and couplers
• Integrated optics