公开(公告)号：US20200044576A1

公开(公告)日：2020-02-06

申请号：US16598178

申请日：2019-10-10

Applicant: ABB Schweiz AG

Inventor： Thomas Besselmann ,  Jörg Pieder

IPC: H02M5/45 ,  H02P27/06 ,  H02P25/022

Abstract: A thyristor bridge of an electrical converter is connected to at least one DC link and including at least one phase leg for each output phase and each phase leg being composed of two series-connected thyristor arms. The thyristor arms of a thyristor bridge are cyclically switched by: determining an upper bound for a firing angle of a thyristor arm, wherein the upper bound is determined from voltage and current measurements; and determining a firing angle for the thyristor bridge, which firing angle determines a switching time of the thyristor arm, wherein the firing angle is determined, such that it is less or equal to the upper bound.