Evaluation of measurement uncertainties in conducted emissions by adjustable speed electrical power drives systems

The evaluation of the uncertainties involved in the measurement of conducted emissions by adjustable speed drive was dealt with. Besides the measurement uncertainty due to the all components of the measurement chain, the uncertainty contribution due to nonrepeatability and the additional one that may arise from configuration set-up and working conditions were investigated. Following the test arrangements suggested by EMC standards, the effects of the reciprocal position of power and motor cables, of the motor cable length, and of the PWM switching frequency used in the test were analyzed in detail and quantified.