Model for coil-less fluxgate

Orthogonal Fluxgates

“…In (Butta & Ripka, 2009b) a model for the working mechanism of the coil-less fluxgate is proposed, based on the effect of helical anisotropy on the magnetization of the magnetic wire, during the saturation process determined by the excitation current. Fig.…”

Influence of the wire length on the of coil-less fluxgate properties of amorphous (Co0.94Fe0.06)72.5Si12.5B15 wire

“…In parallel sensors, the magnetic field produced by the excitation current is parallel to the external field component to be measured, while with orthogonal geometries the directions of these fields are perpendicular to each other [1][2][3][4][5][6][7][8][9]. In this sense, a coil-less fluxgate (CF) sensor can be considered as a new type of orthogonal fluxgate sensor [10][11][12][13]. As its name implies, a CF is a magnetic-field sensor without a coil but with a magnetic wire core.…”

“…As its name implies, a CF is a magnetic-field sensor without a coil but with a magnetic wire core. It has been observed that when a composite or amorphous wire with a helical magnetization component is driven with current pulses that are high enough to saturate the magnetic wire in the circumferential direction, the second harmonic of the output voltage from the wire ends, U wire , varies linearly with the applied external dc magnetic field (H z ) [10][11][12][13]. This makes a CF sensor a good candidate for use as a magnetic-field sensor.…”

“…The CF effect was first reported in Ref. [10] and measurement methods and models were also presented in further studies [11][12][13]. A model based on simultaneous domainwall motion and rotation of the magnetization was used to explain the working principle of the sensor [11].…”

Linearity of Pulse Excited Coil-Less Fluxgate

“…They are similar to "nonlinear giant magneto-impedance (GMI)" sensors [2], [3], but they work at lower frequencies (typically 10 kHz) and they use phase-sensitive detector to obtain linear characteristics. Moreover, they differ on the working principle [4]. First, coil-less fluxgates were excited by a sinewave current flowing into the microwire, which creates a circumferential excitation field .…”