Numerical interpolation methods applied in electromagnetic interference problems

In the paper are evaluated the induced potential in pipeline based on the subdivision of the zone of influence AC Power Lines / electric traction line / gas pipeline, in a relatively great number of sections in order to be able to determine voltages at many positions along the gas pipeline. Is presented a practical case from Cluj, of subdivision of the zone of influence in sections (a circuit model) and is created a special interpolation algorithm for the precise calculation of the induced voltages values in different points on the pipeline taking into account the measured data. Because there are only a set of available reactance measurements, for a continuous function between the magnetic permeability and electrical induced currents, it is necessary to apply numerical interpolation methods and/or nonlinear curve fitting procedures.