US 12,470,153 B2
Method for extending a voltage range of a rectifier, rectifier for carrying out the method, and electrolysis system
Alexander Unru, Baunatal (DE); Andreas Falk, Kassel (DE); Dirk Hermeling, Petershagen (DE); Ralf Juchem, Felsberg (DE); and Marcel Kratochvil, Kassel (DE)
Assigned to SMA Solar Technology AG, Niestetal (DE)
Filed by SMA Solar Technology AG, Niestetal (DE)
Filed on Oct. 28, 2022, as Appl. No. 17/975,945.
Application 17/975,945 is a continuation of application No. PCT/EP2021/059560, filed on Apr. 13, 2021.
Claims priority of application No. 10 2020 111 556.3 (DE), filed on Apr. 28, 2020.
Prior Publication US 2023/0050530 A1, Feb. 16, 2023
Int. Cl. H02M 7/219 (2006.01); C25B 1/04 (2021.01); C25B 9/65 (2021.01); H02M 1/00 (2007.01)
CPC H02M 7/219 (2013.01) [C25B 9/65 (2021.01); H02M 1/0016 (2021.05); C25B 1/04 (2013.01)] 20 Claims
OG exemplary drawing
 
12. An actively-controlled rectifier circuit configured to supply a DC load from an AC grid having an AC voltage, comprising:
an AC rectifier input comprising a plurality of input terminals configured to connect to the AC grid, and a DC rectifier output comprising two output terminals configured to connect to the DC load,
an AC/DC converter comprising an AC-side AC input that is connected to the AC rectifier input, a DC-side DC output that is connected to the DC rectifier output, and a converter circuit arranged between the AC-side AC input and the DC-side DC output, wherein the converter circuit of the AC/DC converter comprises actively controllable semiconductor switches and freewheeling diodes connected in an antiparallel arrangement thereto, and
wherein the AC/DC converter is configured for an exchange of reactive power Q1(t) with the AC grid, and
wherein the actively-controlled rectifier circuit further comprises a control circuit configured to control the semiconductor switches of the AC/DC converter,
wherein the actively-controlled rectifier circuit is configured to:
set a desired DC operating voltage UDC,Soll on the DC-side DC output of the AC/DC converter or on the DC rectifier output, or both, by an actuation of semiconductor switches of the AC/DC converter,
wherein, when the desired DC operating voltage UDC,Soll lies below a value of an amplitude Û4 of the AC voltage on the AC-side AC input of the AC/DC converter, the semiconductor switches of the AC/DC converter are actuated for an exchange of reactive power Q1(t) with the AC grid, which has a voltage-lowering effect upon the amplitude Û4 of the AC voltage at the AC input of the AC/DC converter, such that the amplitude Û4 approaches the desired DC operating voltage UDC,Soll, and
wherein the exchange of the reactive power Q1(t) with the AC grid is executed during or shortly before an electrical connection or an electrical isolation of the DC load to or from the rectifier circuit.