High power system with antiparallel protection diode arrangement
A high power system includes a common DC-bus supply with bus connections, a DC link capacitor bridging the two bus connections and at least two inverter modules connected to the DC-bus supply via the bus connections. Each inverter module includes at least one inverter cell with at least one free-wheeling diode (FWD). The inverter cells are connected to the bus connections via inverter cell connections. A protection diode arrangement is provided antiparallel to the DC link capacitor.
1 . A high power system comprising a common DC-bus supply with bus connections, a DC link capacitor bridging the two bus connections and at least two inverter modules connected to the DC-bus supply via the bus connections, each inverter module comprising at least one inverter cell with at least one free-wheeling diode, wherein the inverter cells are connected to the bus connections via inverter cell connections, wherein a protection diode arrangement is provided anti-parallel to the DC link capacitor, and
wherein the impedance to the protection diode arrangement (Z σ,p ) is significantly smaller than the impedance to the inverter cell (Z σ,i ).
2 . The high power system according to claim 1 , wherein the protection diode arrangement comprises one diode or a multitude of diodes connected in series and/or in parallel to each other.
3 . The high power system according to claim 1 , wherein the impedance to the protection diode arrangement (Z σ,p ) is smaller than 50%, preferably smaller than 10%, of the impedance to the inverter cell (Z σ,i ).
4 . The high power system according to claim 1 , wherein the inverter cells are one-phase or multi-phase connected at inverter cell connections.
5 . The high power system according to claim 1 , wherein a rectifier module and/or a bulk capacitor is connected at the bus connections.
6 . The high power system according to claim 1 , wherein the protection diode arrangement is sized so that its peak current and i 2 t capability are higher than those of the free-wheeling diode.
7 . The high power system according to claim 1 , wherein the protection diode arrangement is provided parallel to the free-wheeling diode.
8 . The high power system according to claim 2 , wherein the inverter cells are one-phase or multi-phase connected at inverter cell connections.
9 . The high power system according to claim 3 , wherein the inverter cells are one-phase or multi-phase connected at inverter cell connections.
10 . The high power system according to claim 2 , wherein a rectifier module and/or a bulk capacitor is connected at the bus connections.
11 . The high power system according to claim 3 , wherein a rectifier module and/or a bulk capacitor is connected at the bus connections.
12 . The high power system according to claim 4 , wherein a rectifier module and/or a bulk capacitor is connected at the bus connections.
13 . A high power system comprising a common DC-bus supply with bus connections, a DC link capacitor bridging the two bus connections and at least two inverter modules connected to the DC-bus supply via the bus connections, each inverter module comprising at least one inverter cell with at least one free-wheeling diode, wherein the inverter cells are connected to the bus connections via inverter cell connections, wherein a protection diode arrangement is provided anti-parallel to the DC link capacitor, and
wherein the protection diode arrangement is sized so that its peak current and i 2 t capability are higher than those of the free-wheeling diode.
14 . The high power system according to claim 13 , wherein the protection diode arrangement comprises one diode or a multitude of diodes connected in series and/or in parallel to each other.
15 . The high power system according to claim 13 , wherein an impedance to the protection diode arrangement (Z σ,p ) is smaller than 50%, preferably smaller than 10%, of an impedance to the inverter cell (Z σ,i ).
16 . The high power system according to claim 13 , wherein the inverter cells are one-phase or multi-phase connected at inverter cell connections.
17 . The high power system according to claim 13 , wherein a rectifier module and/or a bulk capacitor is connected at the bus connections.