Array of rectilinear solenoids for rail current measurement

In this work, an array of rectilinear solenoids connected in series and “embracing” the rail is proposed as a sensor for monitoring the spectral characteristics of noise currents flowing in each rail of a railway line, in the bandwidth covering track circuit functioning and conducted electromagnetic emission. Results here reported are the outcome of a preliminary numerical study (based on the boundary element method) and show feasibility of the proposed idea. Particularly, a formulation based on the magnetic vector potential and the boundary element method reveals to be fast and accurate in solving the electromagnetic problem, and results in a two dimensional formulation. Sensor sensitivity appears to be high enough for the specific application of interest. The outcomes of the proposed analysis have been assessed versus numerical computations based on a commercial finite element software.