CONDUCTED AND RADIATED EMISSIONS IN DISTRIBUTED AUTOMOTIVE DUAL VOLTAGE VEHICLE ELECTRICAL SYSTEMS

In this paper a study on conducted and radiated emissions in new dual voltage (14V/42V) automotive electrical systems is presented. The experimental investigations reported in this paper have the objective of finding out the main characteristics of the involved electromagnetic phenomena taking into account the final application of the drive in the automotive environment. The investigation is particularly focused on an electrical drive loading distributed electrical architecture, where diffused DC/DC power conversion is needed. The DC electrical drive, designed and realized in a prototypical form, is devoted to fuel pumping and it is formed by a 14V DC motor and a DC/DC power converter from 42V to 14V. Suitable experimental measurement systems have been set up to measure electromagnetic conducted disturbances on 42V vehicle power net and radiated emissions. A theoretic and experimental study on different solutions using different switching frequencies of DC/DC converter has been made in order to define the best compromise between the mitigation of electromagnetic emissions and the resulting reduction of filters size. On the basis of the obtained results suitable modelling, designing criteria and useful information for developing dedicated technical standards for the new dual voltage vehicle distributed electrical architecture are proposed.