Problems in the Detection of Quasi-rectangular Magnetic Flux Density Waveforms

The paper focuses on the distortions introduced by low frequency magnetic field meters in the measurement of pulsed or periodic quasi-rectangular waveforms, such as those experienced near welding devices or Magnetic Resonance Imaging (MRI) machines. Starting from the meter frequency response, evaluated by generating reference sinusoidal magnetic fields up to a hundred of hertz, a circuital model is worked out, which reproduces the distortions of the measured signal due to the meter input high pass filter. By making use of the modelled filter, a time domain reconstruction procedure is implemented that allows the reproduction of the actual magnetic field shape starting from the measured behaviour.