Abstract:
The control means of each converter unit produces an output voltage based on reference signals (u* d , u* q ) that are generated from the active and reactive components (P, Q) of each converters output power. A first reference signal for a reactive component of the output voltage (u* q ) is set to zero, thus regulating the reactive component of the output voltage to zero. Therefore, only the active component is contributing to the actual output voltage. The reference signal for the active component of the output voltage (u* d ) is produced based on the active power component (P) with an active power vs. active voltage droop. To synchronize the frequencies of all converter units a reactive power vs. frequency droop is introduced for each converter unit, regulating the frequency based on changes in the reactive power component (Q) of each converter unit. Since the control means of each converter unit produces its reference signals based on the converter units own reactive and active power output, no communication is necessary between the various converter units operating in parallel. Converter units can therefore be placed anywhere without communication.
Abstract:
A semiconductor module (10) comprises a semiconductor chip (12) comprising a Si base layer (14) and a SiC epitaxy layer (16) on the Si base layer (14), the SiC epitaxy layer (16) comprising a semiconductor element (17); an electrical conducting top layer (Mo) (24) for providing an electrical contact of the semiconductor module (10) on a side of the SiC epitaxy layer (16); an electrical conducting bottom layer (Mo) (22) for providing an electrical contact of the semiconductor module (10) on a side of the Si base layer (14); and a failure mode layer (26, 26a, 26b) in contact with a top and/or bottom surface (18, 20) of the semiconductor chip (12) and arranged between the top layer (24) and the bottom layer (22), the failure mode layer (26, 26a, 26b) comprising a metal material (Al, Cu, Ag, Au) (27) adapted for forming a conducting path with the Si base layer (14), for example for forming a eutectic alloy with the Si base layer (14), to short-circuit the semiconductor module (10). The failure mode layer (26, 26b) at the bottom surface (20) of the semiconductor chip (12) may be coated to a core (30) of the bottom layer (22).
Abstract:
A converter comprises a first inverter for converting a first multi-phase AC voltage into a DC voltage and a second inverter for converting the DC voltage into a second multi-phase AC voltage. A method for controlling the electrical converter comprises: switching the first inverter such that a first common mode voltage is generated in the first multi-phase AC voltage; switching the second inverter such that a second common mode voltage is generated in the second multi-phase AC voltage, wherein the first common mode voltage and the second common mode voltage are synchronized such that the first common mode voltage and the second common mode voltage cancel each other at least partially.
Abstract:
A rectifier circuit for at least one phase (R, S, T) is disclosed, which includes a first vector group system (1), provided for each phase (R, S, T), comprising a first main vector group (4), formed by a power semiconductor switch and a capacitor (3), connected to the power semiconductor switch (2) and with at least one intermediate group (7), formed by two serially-connected controlled power semiconductor switches (5) and a capacitor (6), said intermediate group(s) (7) being connected to the first main vector group (4). The first vector group system further comprises a second main vector group (9), formed by a power semiconductor switch (8), whereby the or an intermediate group (7) is connected to the second main vector group (9). According to the invention, the rectifier circuit may be simplified and the incidence of faults reduced, whereby the power semiconductor switch (2), the first main vector group (4) and the power semiconductor switch (8) in the second main vector group (9) are each formed from a passive uncontrolled electronic component (11) with unidirectional current flow. To improve the storage of electrical energy with several phases (R, S, T), the first vector group systems (1) of the phases (R, S, T) are connected to each other in parallel.
Abstract:
A converter comprises a first inverter for converting a first multi-phase AC voltage into a DC voltage and a second inverter for converting the DC voltage into a second multi-phase AC voltage. A method for controlling the electrical converter comprises: switching the first inverter such that a first common mode voltage is generated in the first multi-phase AC voltage; switching the second inverter such that a second common mode voltage is generated in the second multi-phase AC voltage, wherein the first common mode voltage and the second common mode voltage are synchronized such that the first common mode voltage and the second common mode voltage cancel each other at least partially.
Abstract:
A modular multi-level converter (10) for converting a DC voltage into an AC voltage comprises a first row (14) and a second row (18) of converter cells (16, 20), each converter cell (16, 20) comprising a cell capacitor (Ccell, Ccell') and semiconductor switches (34, 36, 34', 36') adapted for connecting the cell capacitor to an output of the converter cell (16, 20) and for bypassing the cell capacitor. The first row (14) of converter cells (16) interconnects a positive DC link connection point (22a) and a negative DC link connection point (22c), wherein the first row (14) of converter cells (16) comprises an upper pair and a lower pair of series-connected strings (24a, 24b, 24c, 24d) of series-connected converter cells (16), wherein the upper pair of strings (24a, 24b) connects the positive DC link connection point (22a) with a neutral DC link connection point (22b) and provides an upper intermediate connection point (26a) between the strings (24a, 24b) and the lower pair of strings (24c, 24d) connects the negative DC link connection point (22c) with the neutral DC link connection point (22b) and provides a lower intermediate connection point (26b) between the strings (24c, 24d). The second row (18) of converter cells (20) comprises a pair of strings (28a, 28b) of series-connected converter cells (20) interconnecting the upper intermediate connection point (26a) and the lower intermediate connection point (26b) and provides an AC connection point between the strings (28a, 28b). The converter cells (16) of the first row (14) have a first cell capacity (Ccell') and the converter cells (20) of the second row (18) have a second cell capacity (Ccell) higher than the first cell capacity (Ccell'). The converter cells (16) of the first row (14) have a capacitor switch (36'), which interconnects the cell capacitor (Ccell') with the outputs (38) and which has a lower current rating than a main switch (34') of the converter cells (16) of the first row (14) connected in parallel to the cell capacitor (Ccell'). The converter cells (20) of the second row (18) have a capacitor switch (36) and the current rating of the capacitor switch (36') of a converter cell (16) of the first row (14) is smaller than a current rating of the capacitor switch (36) of a converter cell (20) of the second row (18).
Abstract:
The invention specifies a fuel/electric drive system having an internal combustion engine (1), having a generator (2) which is driven by the internal combustion engine (1) and has a first stator winding set (A), having a first rectifier (3) which is connected to the first stator winding set (A) at the AC voltage end and to a first DC voltage circuit (4) at the DC voltage end, and having a first inverter (5) which is connected to the first DC voltage circuit (4) at the DC voltage end and to a drive motor (6) at the AC voltage end. In order to increase the robustness and availability of the fuel/electric drive system, the generator (2) has a second stator winding set (B), with a second rectifier (7) being connected to the second stator winding set (B) at the AC voltage end and to a second DC voltage circuit (8) at the DC voltage end, and a second inverter (9) being connected to the second DC voltage circuit (8) at the DC voltage end and to the drive motor (6) at the AC voltage end.