Abstract: A power supply system for an electric arc furnace includes an AC input connectable to an electrical grid and an AC output for supplying at least one power electrode of the arc furnace; a resonant circuit interconnected between the AC input and the AC output. The resonant circuit includes a controllable bypass switch for connecting and disconnecting a circuit input and a circuit output of the resonant circuit and a capacitor and a main inductor connected in parallel with the bypass switch.

Abstract: A power supply system for an electric arc furnace includes an AC input connectable to an electrical grid and an AC output for supplying at least one power electrode of the arc furnace; a resonant circuit interconnected between the AC input and the AC output. The resonant circuit includes a controllable bypass switch for connecting and disconnecting a circuit input and a circuit output of the resonant circuit and a capacitor and a main inductor connected in parallel with the bypass switch.

Abstract: A power supply system for an electric arc furnace includes an AC input connectable to an electrical grid and an AC output for supplying at least one power electrode of the arc furnace. The power supply system further includes a converter circuit interconnected between the AC input and the AC output. The converter circuit includes at least one converter cell with a capacitor and semiconductor switches for series connecting the capacitor between a circuit input and a circuit output of the converter circuit.

Abstract: A power semiconductor device includes a Si chip providing a Si switch and a wide bandgap material chip providing a wide bandgap material switch, wherein the Si switch and the wide bandgap material switch are electrically connected in parallel. A method for controlling a power semiconductor device includes: during a normal operation mode, controlling at least the wide bandgap material switch for switching a current through the power semiconductor device by applying corresponding gate signals to at least the wide bandgap material switch; sensing a failure in the power semiconductor device; and, in the case of a sensed failure, controlling the Si switch by applying a gate signal, such that a current is generated in the Si chip heating the Si chip to a temperature forming a permanent conducting path through the Si chip.

Abstract: A power semiconductor device includes a base plate; a Si chip including a Si substrate, the Si chip attached to the base plate; a first metal preform pressed with a first press pin against the Si chip; a wide bandgap material chip comprising a wide bandgap substrate and a semiconductor switch provided in the wide bandgap substrate, the wide bandgap material chip attached to the base plate; and a second metal preform pressed with a second press pin against the wide bandgap material chip; the Si chip and the wide bandgap material chip are connected in parallel via the base plate and via the first press pin and the second press pin; the first metal preform is adapted for forming a conducting path through the Si chip, when heated by an overcurrent; and the second metal preform is adapted for forming an temporary conducting path through the wide bandgap material chip or an open circuit, when heated by an overcurrent.

Abstract: A power semiconductor device includes a base plate; a Si chip including a Si substrate, the Si chip attached to the base plate; a first metal preform pressed with a first press pin against the Si chip; a wide bandgap material chip comprising a wide bandgap substrate and a semiconductor switch provided in the wide bandgap substrate, the wide bandgap material chip attached to the base plate; and a second metal preform pressed with a second press pin against the wide bandgap material chip; the Si chip and the wide bandgap material chip are connected in parallel via the base plate and via the first press pin and the second press pin; the first metal preform is adapted for forming a conducting path through the Si chip, when heated by an overcurrent; and the second metal preform is adapted for forming an temporary conducting path through the wide bandgap material chip or an open circuit, when heated by an overcurrent.

Abstract: A power semiconductor device includes a Si chip providing a Si switch and a wide bandgap material chip providing a wide bandgap material switch, wherein the Si switch and the wide bandgap material switch are electrically connected in parallel. A method for controlling a power semiconductor device includes: during a normal operation mode, controlling at least the wide bandgap material switch for switching a current through the power semiconductor device by applying corresponding gate signals to at least the wide bandgap material switch; sensing a failure in the power semiconductor device; and, in the case of a sensed failure, controlling the Si switch by applying a gate signal, such that a current is generated in the Si chip heating the Si chip to a temperature forming a permanent conducting path through the Si chip.