Transient overvoltages at motor terminals and highfrequency common-mode currents in PWM drive systems have been extensively investigated in the last fifteen years. Nevertheless, some issues concerning such quantities still remain unclear. That is the case of the converter-to-motor cabling influence on the intensity of these high-frequency voltages and currents. Filters of different types have been traditionally used to mitigate these undesired phenomena. However, due to their cost, volume and losses, they can't be considered the ultimate solution of the problem. In this paper, typical industrial cable arrangements will be characterized in terms of the generated transient overvoltages and common-mode currents. It will be shown that variations in the range of 10 to 40 % in the peak values of these quantitites can take place due to different cable disposition. Thus, it can be concluded that special care in the cable installation can lead to significant reduction in these undesired phenom-ena, which in turn downsizes the required filter.

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We report a simple method to accurately determine the threshold and the exponent ν of the Bak-Sneppen model and also investigate the BS universality class. For the random-neighbor version of the BS model, we find the threshold x * = 0.33332(3), in agreement with the exact result x * = 1/3 given by mean-field theory. For the one-dimensional original model, we find x * = 0.6672(2) in good agreement with the results reported in the literature; for the anisotropic BS model we obtain x * = 0.7240(1). We study the finite size effect x * (L) − x * (L → ∞) ∝ L −ν , observed in a system with L sites, and find ν = 1.00(1) for the random-neighbor version, ν = 1.40(1) for the original model, and ν = 1.58(1) for the anisotropic case. Finally, we discuss the effect of defining the extremal site as the one which minimizes a general function f (x), instead of simply f (x) = x as in the original updating rule. We emphasize that models with extremal dynamics have singular stationary probability distributions p(x). Our simulations indicate the existence of two symmetry-based universality classes.