EMI characteristics of power electronics switching circuits

While many aspects, such as screening and gasketing arrangements will immediately be transferable from existing EMC applications, a number of issues are specific to the operation of high current, high voltage semiconductor switching circuits. The paper endeavours to address the problem by establishing firstly, in broad terms the range of frequencies over which RF emissions are significant relative to existing test standard thresholds, secondly the extent to which the operation of power electronic devices gives rise to EM noise over and above that associated with perfect switching behaviour and thirdly the influence of device selection. The paper concludes by highlighting a potential source of measurement error which was identified during the present investigation