Analysis of the topology and response of surge protection devices (SPD) network to dangerous voltage/current waves

The increasing use of complicated and sensitive communication and electronics devices and systems, brought about a marked increase of failures and outages due to dangerous induced voltages. The main reason for these induced voltages are direct and indirect lightning strokes. The suppression of these dangerous voltages or current waves is achieved by so-called surge protection devices (SPDs). There is a rather wide range of SPDs and SPD networks with nonlinear voltage/current characteristics and various response times. The induced voltages are determined by several factors. One of the main factors is the topology of the power system to be protected with all its elements and the incoming and outgoing lines. These lines include communication, data and power feeding lines. The study of the induced voltage waves traveling in the system with their amplitudes and times is the first step in designing an efficient protection system. The next step is to study various combinations of SPDs in order to suppress these dangerous voltages and deal with the existing high energies in the system. This is a complicated problem due to wide varying suppression capabilities of SPDs and the wide range of their response times (from a few psec to msec). The analysis takes into account the mutual influence of SPDs. With a better understanding of the dynamic behavior of the SPD networks, more efficient protection systems can be designed.