Detector and method thereof for determining magnetic flux based on electromotive force induced by an excitation current

摘要

A magnetic flux detector has a core member and an armature member. The core member generates a magnetic flux by an exciting coil receiving an excitation current controlled by an excitation current controller. The magnetic flux detector also has a search coil provided in a magnetic path for the magnetic flux, and a magnetic flux calculator, which determines the magnitude of the magnetic flux by measuring an electromotive force induced in the search coil by a change in the magnetic flux. The excitation current controller controls the excitation current to increase from zero to a predetermined value during a first predetermined time period and then to decrease to zero during a second predetermined time period. The magnetic flux calculator determines the magnitude of the magnetic flux based on the integrated electromotive forces during the first and second time periods.