Using coreless hall effect sensor for accurate current measurement in ZigBee based wireless sensor network

Abstract

This study combines coreless Hall effect current transformers (HCTs), ZigBee communication, and a quiescent voltage adjustment to develops a new current measurement method for non-straight conducting wires. The proposed design includes the unique characteristics of low cost, low power consumption, and wireless communication capability that makes it flexible for current measurement at different environments. In addition, the quiescent voltage adjustment enable the adjustment of DC voltage level to eliminate the DC 2.5±0.05 V quiescent voltage requirement in each Hall sensor for an easy signal transformation in back-end monitoring systems. Simulation and measurement results show that HCTs can eliminate the problems of asymmetric magnetic flux density distributions outside the conducting wire which originated from its non-straight structure or its asymmetric cross-section. The accuracy class of the current measurements using HCTs can meet the 0,5 class according to IEC standard and their current waveforms do not suffer the saturation from using traditional CTs.