Application of a non-linear Method of Moments to predict microfluxgates output

An original model to predict microfluxgates output voltage is presented. Firstly, a non-linear fitting of the magnetic cores behaviour is detailed and compared to measurements. Then, it is used in an analytical model to predict the second harmonic of a microfluxgate output. Compared to measurements, this model appears to be inefficient mainly because of a bad estimation of the demagnetizing field. That is why an anhysteretic non-linear numerical model, based on the Method of Moments, is proposed to correctly compute magnetization on each point of the cores and at any moment. Output voltage is finally deduced from magnetization variation. Sensitivity measurements of the second harmonic on a microfluxgate have confirmed this approach.