ABSTRACT
Hybrid current transformers utilize conventional means such as a magnetic core, Rogowski coil, or shunt to convert a high voltage current into a voltage signal and then encode that signal into optical information for transmission to ground via an optical fiber. This chapter presents electronic transformers that work with optically powered converter electronics on high voltage and sensors, where a piezoelectric transducer converts the alternating voltage signal in a periodic piezoelectric deformation, measured with an optical fiber interferometer or a fiber Bragg grating. Further hybrid current sensors include light intensity modulating devices such as micro-machined structures modulated by the current magnetic field.
