US 12,334,812 B2
Method and a device for compensating a faulty switch in a multi-level flying capacitor converter
Hemant Bishnoi, Aargau (CH); Sami Pettersson, Dietikon (CH); Mario Schweizer, Rütihof (CH); Daniel Christen, Uster (CH); and Gernot Riedel, Baden-Rütihof (CH)
Assigned to ABB Schweiz AG, Baden (CH)
Filed by ABB Schweiz AG, Baden (CH)
Filed on Sep. 13, 2022, as Appl. No. 17/943,693.
Claims priority of application No. 21196669 (EP), filed on Sep. 14, 2021.
Prior Publication US 2023/0083355 A1, Mar. 16, 2023
Int. Cl. H02M 1/32 (2007.01); H02M 1/36 (2007.01); H02M 7/483 (2007.01)
CPC H02M 1/322 (2021.05) [H02M 1/325 (2021.05); H02M 1/36 (2013.01); H02M 7/4837 (2021.05)] 12 Claims
OG exemplary drawing
 
1. A method for compensating a faulty switch in a multi-level flying capacitor converter, wherein each converter level of the multi-level flying capacitor converter comprises:
a converter capacitor arranged in parallel to an input of the multi-level flying capacitor converter;
a first converter switch and a second converter switch, the first converter switch being arranged between a first end of the converter capacitor, and the second converter switch being arranged between a second end of the converter capacitor;
a first bypass switch arranged in parallel to the first converter switch; and
a second bypass switch arranged in parallel to second converter switch;
wherein the method comprises:
detecting a faulty converter level, wherein the faulty converter level comprises at least one of the first converter switch and the second converter switch being faulty;
stopping the multi-level flying capacitor converter;
discharging all capacitors arranged in parallel to the input of the multi-level flying capacitor converter, wherein all capacitors comprise the converter capacitors, an input capacitor, and an output capacitor;
closing the first bypass switch and the second bypass switch of a level containing the first or second converter switch that is faulty;
adapting a modulation of the first and second converter switches of other converter levels by adjusting a phase shift between the other converter levels; and
restarting the multi-level flying capacitor converter.