Error analysis of the rough model of the symmetric dual-optical signal detection based MOCT

Abstract Symmetric double signal analysis based magneto optical current transformer(MOCT) is usually based on a rough model to calculate the primary current, but due to the use of approximate calculation, the primary current and output voltage is not as strictly linear relationship, so the rough model introduce some errors which exceed the national standard national electronic current transformer Standards 0.2 or 0.5 class accuracy requirements when the primary current increase outside a certain range, at this time the rough model can not be used to measure the current. As the voltage RMS and current RMS usually are used in the power system measurement, this article will analyze relationship between the actual output voltage RMS and the current RMS and obtain the relationship of the approximate calculation caused error and the increasing current RMS, and obtain the current measurement range that meet the accuracy requirement of the national standard.