Aiming at the problem of heavy flux error in current transformer’s transient characteristics testing caused by sensor zero drift and noise interference

a multi-stage measuring method based on Kalman filtering data fusion means is proposed.Through analysis on the effect of the sensor’s error on measuring result

the sensor’s measuring error is identified.According to the ferromagnet’s electro-magnetic relationship and the characteristics of all sensors

using Kalman filtering’s good correction ability

effect of error on high-precision measurement is eliminated.The experimental result shows that after the process of Kalman filtering’s treatment

not only is the error accumulation caused by zero drift eliminated

but also the test curve is accurate and smooth.