White Light Sensing Systems for High Voltage Measuring Using Electro-Optical Modulators as Sensor and Recovery Interferometers

There are several known issues related to the use of electro-optical sensors as measuring devices. In applications intended for use in measuring currents and potentials in high voltage electric power systems, optical sensor systems must attend severe specifications, such as: large withstand voltage of the primary sensor, high accuracy (better than 0,5%, in case of revenue metering), long term stability of scale factor, large dynamic range (>50 dB, in some applications for protection purpose) and relatively wide frequency response range (of several kHz, in case that harmonics content evaluation is needed). However, the potential advantages arising from the use of optical fiber sensors as instrument transformers (ITs) in substitution to conventional electromagnetic transformers, may explain the intensive efforts that have been done during the last 30 years to develop optical ITs.