PSNet - fyi
Low-Frequency Transients and Impedance in the Power Mains Considering Line
Loading
by Forti, Millanta and Carobbi
IEEE Transactions on Electromagnetic Compatibility, Vol 38, No 3, Aug 1996
Abstract - Protection against the transients originated by the connection or
disconnection of loads in the power mains is of fundamental importance for the
electric energy quality. The knowledge of the parameters of the disturbances
and of the characteristics of the mains lines is essential for the mitigation of
the unwanted phenomena and for the design of protection measures. This paper
offers a lumped-constant analysis of the influence of the network loads on the
transient waveshapes, and on the impedance seen when looking into the mains.
The complex problem involving two loads and two line sections is reduced to a
simplified model permitting analytical treatment with the consequent possibility
of prediction and of extraction of the important features. The simplifying
assumptions are 1) the line losses are low, and 2) the distance between the
loads involved in the transient is short with respect to the total line length.
The approximation limits are pointed out and the experimental validation
demonstrates excellent agreement. Only the more significant case involving
capacitive loading of the line is worked out in detail. Other cases of interest
also involving resistive-inductive loading have been treated and are here
delineated in summary.
:>) submitted by Pete Perkins
[email protected]
