1 research outputs found
Low-Voltage Electric Arc Reconstruction From Magnetic Field Measurements
The knowledge of current density distribution gives
important information for the study of the electric arc in lowvoltage
circuit breakers. Available experimental approaches to
investigate the electric arc behavior include electrical measurements,
optical, and magnetic diagnostic techniques. However,
noninvasive experimental methods able to obtain the electric arc
current density cannot be found in the literature. This article
presents a nonintrusive diagnostic technique able to reconstruct
the 3-D electric arc current density from its magnetic field
measurements by solving a magnetic inverse problem. This
inverse problem is known to be ill-posed, and Tikhonov regularization
is used together with the L-curve method. Zero-divergence
condition on the current density and boundary conditions are
incorporated into the formulation of the inverse problem with
the help of Whitney elements. A magnetic field measurement
system is developed based on a Hall-effect magnetic sensor array
and a data acquisition board. The sensor array is composed
of 64 mono-axial analog-bipolar sensors distributed in eight
columns and eight rows. The maximum measurable magnetic
field of the sensor is 9 mT. The data acquisition board consists
of eight analog-to-digital converters with a maximum sampling
rate of 200 kHz and a 16-bits resolution. Experimental tests are
carried out using the proposed method in order to study the arc
dynamics. The reconstructions are compared with those of an
optical diagnostic technique based on a charge-coupled device
(CCD) camera