Fiber Optic Based Leakage Current Measurement and its Possible Length to Achieve the Safety Limit

This article shows a novel approach to measure the electrical Leakage Current or known also as residual current using Fiber Optic (FO). It differs over common Residual Current Device (RCD) device in assuring electrical safety in power system networks as it uses light as its medium. The main challenge of this technique was posed by the requirement of high magnetic fields in FO-based measurements. Therefore, compromising it by increasing the length of the magnetic fields' exposure is certainly logical with FO. Furthermore, the leakage current limit could be as low as 0.5mA by adhering to the IEC60601 standard. The same principle of Magneto Optical Effect (MOE) with Faraday Effect (also known as Faraday rotation) would be utilized. In this study, a common silica core FO with a low Verdet constant characteristic would be used. The proposed technique would be utilizing FO by coiling it around a current-carrying wire so that light experiences the Faraday Effect for a greater distance. From the simulation, FO based measurements with up to 15 km can still be utilized with a power reduction until 50% due to Attenuation Loss from a laser power source of only 100 mW. This implies that more potential applications are able to contribute to advancements in terms of energy efficiency with the many benefits of FO in comparison to the use of electrical wire with its magnetic induction.