US 12,323,073 B2
Method for operating a power electronic converter device with floating cells
Ioannis Tsoumas, Zürich (CH); Tobias Geyer, Ennetbaden (CH); Mario Schweizer, Rütihof (CH); Eduardo Rohr, Camberwell (AU); Frederick Kieferndorf, Baden (CH); Wim Van-der-Merwe, Ennetbaden (CH); Manuel Vetterli, Basel (CH); and Christian Meier, Ennetbaden (CH)
Assigned to ABB Schweiz AG, Baden (CH)
Appl. No. 17/789,586
Filed by ABB Schweiz AG, Baden (CH)
PCT Filed Dec. 17, 2020, PCT No. PCT/EP2020/086775
§ 371(c)(1), (2) Date Jun. 28, 2022,
PCT Pub. No. WO2021/136677, PCT Pub. Date Jul. 8, 2021.
Claims priority of application No. 19220176 (EP), filed on Dec. 31, 2019.
Prior Publication US 2023/0042964 A1, Feb. 9, 2023
Int. Cl. H02M 7/487 (2007.01); H02M 1/12 (2006.01); H02M 1/15 (2006.01); H02M 7/49 (2007.01); H02M 7/5395 (2006.01); H02M 1/00 (2006.01)
CPC H02M 7/487 (2013.01) [H02M 1/12 (2013.01); H02M 1/15 (2013.01); H02M 7/49 (2013.01); H02M 7/5395 (2013.01); H02M 1/0067 (2021.05); H02M 1/0095 (2021.05)] 13 Claims
OG exemplary drawing
 
13. A power electronic converter device for an electrical power conversion system, the power electronic converter device comprising: a converter circuit including an input side with input terminals, an output side with at least one AC output terminal, a first converter with semiconductor devices connected to the input terminals and at least one second converter connected between an AC output of the first converter and an AC output terminal, the at least one second converter comprising at least one floating cell with a DC intermediate circuit and semiconductor devices; and a control device for driving the semiconductor devices of the at least one floating cell, wherein the control device is configured to:
switch the semiconductor devices of the at least one floating cell at switching instants determined with optimized pulse patterns or carrier-based pulse width modulation;
determine a fundamental voltage component for the at least one floating cell, wherein the fundamental voltage component depends on a difference between an actual voltage VC AF of the DC intermediate circuit of the at least one floating cell and a reference value VC AF* for a voltage of the DC intermediate circuit;
generate the fundamental voltage component in the actual voltage of the DC intermediate circuit of the at least one floating cell by modifying the switching instants, such that the actual voltage VC AF of the DC intermediate circuit is in a given reference voltage range;
switch the semiconductor devices of the first converter at switching instants determined with optimized pulse patterns or carrier-based pulse width modulation; and
generate a fundamental voltage component in a voltage output by the first converter by modifying the switching instants applied to the first converter, wherein the fundamental voltage component in the voltage output by the first converter is determined based on the fundamental voltage component determined for the at least one floating cell,
wherein the fundamental voltage component of the voltage output by the first converter is modified, such that a fundamental component of a voltage at the at least one AC output terminal is kept constant; and/or wherein the fundamental voltage component of the at least one floating cell generated by the at least one floating cell is canceled out by the fundamental voltage component of the voltage output by the first converter.