公开(公告)号：US20220216803A1

公开(公告)日：2022-07-07

申请号：US17601312

申请日：2020-03-03

Applicant: ABB Schweiz AG

Inventor： Mario Schweizer ,  Tobias Geyer ,  Ioannis Tsuomas

IPC: H02M7/487 ,  H02M1/00

Abstract: An electrical converter (10) comprises a main converter (12) for generating a first output voltage (u1abc) and a converter cell (14a) for converting the first output voltage (u1abc) into a second output voltage (u2abc). A method for operating an electrical converter (10) comprises: receiving a reference voltage (v*abc) for the electrical converter (10); pulse width modulating the reference voltage (v*abc) with a first modulation frequency for generating a first switching signal (s1abc) for the main converter (12); switching the main converter (12) with the first switching signal (s1abc) to generate the first output voltage (u1abc); estimating the first output voltage (v1abc) from the first switching signal (s1abc); determining a voltage error (v*2abc) by subtracting the estimated first output voltage (v1abc) from the reference voltage (v*abc); pulse width modulating the voltage error (v*2abc) with a second modulation frequency, which is higher than the first modulation frequency, for generating a further switching signal (s2abc, s3abc) for the converter cell (14a); and switching the converter cell (14a) with the further switching signal (s2abc, s3abc) to generate the second output voltage (u2abc).