Measurement of Distorted Power-Frequency Electric Field With Integrated Optical Sensor

The measurement of the distorted power-frequency electric field needs to meet some special requirements such as appropriate insulation, quick response, passive measurement, and small size. In this paper, based on the Pockels effect, an integrated optical sensor is designed and used for measuring distorted power-frequency electric field for the first time. The input-output characteristic, frequency response, and temperature characteristic of the sensor are studied. The data show that the sensor has a linear measurable range from 100 V/m to 27 kV/m, a 3-dB bandwidth from 20 Hz to 10 MHz, with good temperature stability. The developed sensor is used to measure the distorted electric field and is compared with the Narda-NBM-550 sensor. The relative errors between the measured values of these two sensors and the simulation values obtained by the finite-element method are calculated. It is noted that the relative errors of the integrated optical sensor in different positions are within 12%. However, the Narda-NBM-550 sensor performs poorly at the edges of the barrier with an error of 22%. In conclusion, the findings demonstrate that the integrated optical sensor developed in this paper is more suitable for measuring distorted power-frequency electric field than the Narda-NBM-550 sensor. Further research needs to focus on the measurement of the 3-D distorted power-frequency electric field.