Calculation of Alternating Current Losses in Steel Pipes Containing Power Cables

A new method for calculating eddy current losses in steel pipes of pipe-type power cables is described. The method, based on the fundamentals of electromagnetic theory, incorporates information obtained from the steel magnetization curve which is used to establish the effective permeability. The resulting procedure has no adjustable parameters. A good agreement is obtained between the results of calculations and measurements of a.c. to d.c. resistance ratios, for several cable systems.