Suspension Insulator String Parameters: Analytical Calculations Based on the Potential Distribution

This paper addresses a research gap: the inverse problem of determining the distribution of voltage across the suspension insulator string, i.e., computing string parameters such as disk self-capacitances and stray capacitances from a given complex potential distribution. Specifically, we derived explicit formulae for computing the insulator string parameters from a system of non-homogeneous recurrence relations that describe the insulator string lumped-parameter model. Consequently, given the disk self-admittances, we obtained closed formulae for calculating the stray capacitances to the grounded tower and the line conductor for a known complex potential distribution. We also derived the formula for computing the disk self-admittances for a specified complex potential distribution, provided the disk stray capacitances are known. Using the formulae, we gave two examples for computing the insulator string parameters due to certain voltage distributions considered in other papers. Finally, we applied the formulae in designing an insulator string.