New Quality of Current Measurement in Power Switchgear with the Use of PCB Sensors

Abstract

In the paper separable and non-separable current transducers using printed circuit board technology have been presented. The transducers are characterized by a measurement range from a fraction of an ampere to 100 kA, perfect linearity and measurement bandwidth from 10 Hz to 20 kHz. The PCB technology makes it possible to obtain very high repeatability of transducer electrical parameters. The spread in the value of the most important parameter – the sensitivity, in a typical production lot is less than 0.5%. The same transducer can work simultaneously with protection device and power meter. The wide bandwidth of the transducer made in PCB technology enables its use in power quality analyzers. The additional advantage of PCB technology is the possibility to integrate the transducer with signal processing circuits. The construction of separable current transducer using PCB technology makes it possible to install it over the wire with measured current without disconnecting primary circuits. Transducers made in PCB technology have very symmetric secondary winding which is a crucial factor in ensuring that the measurement results are largely independent of the external magnetic fields not associated with the measured current.