US 11,658,585 B2
Arc furnace power supply with resonant circuit
Peter Karl Steimer, Ehrendingen (CH)
Assigned to ABB Schweiz AG, Baden (CH)
Appl. No. 17/622,439
Filed by ABB Schweiz AG, Baden (CH)
PCT Filed May 8, 2020, PCT No. PCT/EP2020/062915
§ 371(c)(1), (2) Date Dec. 23, 2021,
PCT Pub. No. WO2020/259907, PCT Pub. Date Dec. 30, 2020.
Claims priority of application No. 19182898 (EP), filed on Jun. 27, 2019.
Prior Publication US 2022/0352828 A1, Nov. 3, 2022
Int. Cl. H02M 5/257 (2006.01); H05B 7/144 (2006.01); H02M 5/12 (2006.01); H02M 5/06 (2006.01); H05B 7/148 (2006.01)
CPC H02M 5/12 (2013.01) [H02M 5/06 (2013.01); H02M 5/2573 (2013.01); H05B 7/144 (2013.01); H05B 7/148 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A power supply system for an electric arc furnace, the power supply system comprising:
an AC input connectable to an electrical grid and an AC output for supplying at least one power electrode of the arc furnace; and
a resonant circuit interconnected between the AC input and the AC output;
wherein the resonant circuit comprises a controllable bypass switch for connecting and disconnecting a circuit input and a circuit output of the resonant circuit;
wherein the resonant circuit comprises a capacitor and a main inductor connected in parallel with the bypass switch; and
wherein the power supply system comprises a controller for controlling the bypass switch, such that a circular current is formed in the resonant circuit, when the bypass switch is closed, which lowers a current through the power supply system.