Optical Current Transducers and Error Sources in Them: A Review

Abstract

Optical current transducers are developed vastly in recent decades. For an accurate transducer achievement, different factors should be considered. This paper reviews the most important sources of errors in these devices. First, the main types of transducers are introduced. Afterwards, the effects of temperature and vibration on their operational performance are discussed. Then, the birefringence is addressed which is the main error source in the transducers. In each part, the proposed solutions in the papers are reviewed. Finally, the effect of nonideal optical parts on the measurement accuracy is discussed. The paper serves as a brief introduction to common errors in optical current transducers.Index Terms-Birefringence, Error decrement, Optical current transducers, Review.1530-437X (c)

Fiber Optic Sensors Based on the Faraday Effect

“…Birefringence also complicates temperature dependence [ 33 ]. The general conclusion is that birefringent materials should be avoided if possible for sensing purposes, or that birefringence should be compensated for [ 34 , 35 , 36 , 37 , 38 , 39 , 40 ]. Unfortunately, birefringence is inevitable in the coiled optical fiber (OF), and stress or the Pockels effect can induce birefringence in crystals.…”

An Optical Current Sensor Based on Radial Grating-Polarizer Detection

“…In this paper the rated current of OCS is 300 A (root mean square, RMS) the measurement range is 200% of the rated current and the maximum Faraday rotation angle is 45°, so the length of air gap can be calculated as 4 …”

“…Optical current sensors (OCSs) compared with conventional sensors, have the advantages of light weight, small size, anti-electromagnetic interference, outstanding electrical isolation, possibility for both alternate current (AC) and direct current (DC) measurement, no magnetic saturation, lower power consumption, wide bandwidth and safety [1]- [3]. Therefore, the OCSs are extremely attractive for high voltage applications and have developed vastly in recent years [3] [4].…”

Research on dichotomous optical current sensing technology

“…[5][6][7][8][9] Although OCTs have many advantages, they still have some disadvantages that restrict their application in power grids. For example, the luminous intensity output decreases after long-term operation, which leads to a low reliability, 10,11 and the measurement accuracy needs to be improved. The operational reliability is related to various factors such as the sensor head structure.…”

“…Vivaldi antenna with an exponential tapered geometry is widely used in many applications due to its characteristic of ultra-wideband performance. [10][11][12] Besides, the configuration of rectifier also has different types, such as single-diode rectifier, 13 voltage doubler rectifier 14 and fullwave Greinacher rectifier. 15 To realize the impedance matching between antenna and rectifying circuit, a matching network is of great importance which can also improve the…”