Calculation of frequency-dependent parameters of pipe-type cables:: Comparison of methods

In this paper the results of four analytical methods for the calculation of frequency-dependent parameters of pipe type cables are compared. Method 1 is Ametani's method, which neglects proximity effects among conductors and assumes that the pipe has infinite thickness. Method 2 is a proposed method that takes proximity effects into account and assumes that the pipe has infinite thickness. Method 3 is also a proposed method, but neglects proximity effects among conductors and assumes that the pipe has finite thickness. Method 4 is Kane's method, which takes proximity effects into consideration and assumes that the pipe has finite thickness. With respect to Kane's method, the results obtained from the three first methods yield relative errors as high as 95%, particularly at low frequencies.