Comparison of power supply topologies for industrial drives, based on safety and EMC European standards or directives

摘要

European Directives on EMC and safety are discussed to point-out their impact on medium-power low-voltage drive supplies. By merging the different specifications, technical parameters are derived, discussing shortfalls and overpositions. A generic supply system is defined and three different cases are analyzed. Harmonics emission calculations are reported as a function of inductance at nominal operation. Immunity specifications are discussed, pointing-out that voltage impulses, from safety standards, and voltage unbalance, from product family specifications, may take the heaviest impact on drive design. This is shown by calculations on either inductor overrating or power derating, for each considered case.