Source: EDN article
by Bertram Schott & Adrian Michael.
Wirewound power resistors are usually rated with respect to continuous power, which can be insufficient for e-mobility applications. A typical application is the pre- and discharge of large capacitors, often referred to as “soft start.” In this case the pulse-handling capability of the resistor is also very important. This capability can be determined over a large range of pulse durations by combining theoretical basics with finite element simulations of the respective thermal performance. The results can be generalized so that changing customer specifications can quickly be evaluated and suitable resistors suggested. (more…)