Non-iterative algorithm for computation of the prospective permissible touch voltage according to EN 50522

摘要

The prospective permissible touch voltage computation algorithm can be found in the international standards and technical specifications. By combining values of the total human body impedance and values of the permissible body current, extracted from tables and figures, the relevant permissible touch voltage as a function of the fault duration is obtained using an iterative process. In this paper, a simple and robust non-iterative algorithm for computation of the prospective permissible touch voltage according to EN 50522 for chosen fault duration is presented. In proposed algorithm, computation of the prospective permissible touch voltage is reduced to linear combination of permissible touch voltage for a current path hand to hand and permissible body current.For chosen fault duration, permissible touch voltage for a current path hand to hand and permissible body current are computed using piecewise cubic Hermite interpolation and given sampled values of these functions and sampled values of their derivatives with respect to fault duration.