AC-to-DC converter system
A converter system for converting a three-phase or a single-phase AC voltage into a DC voltage, wherein the converter system includes three converter branches, each converter branch including a first input and a second input to be supplied with a single-phase AC voltage and a first output and a second output providing a DC voltage; wherein each converter branch includes an AC-to-DC stage and a DC-to-DC stage, which are connected between the first and second input and the first and second output; wherein the converter system is configured for interconnecting the first input of each converter branch with a phase of a three-phase grid and for interconnecting the first inputs of the converter branches with a phase of a single-phase grid; wherein the converter system is configured for interconnecting the second inputs, which are interconnected with each other, of the converter branches with a neutral point of the three-phase grid or the single-phase grid; and wherein the converter system includes one or more controllers adapted for controlling the converter branches independently from each other.
1. A converter system for converting a three-phase or a single-phase AC voltage into a DC voltage;
wherein the converter system comprises three converter branches, each converter branch comprising a first input and a second input to be supplied with a single-phase AC voltage and a first output and a second output providing a DC voltage;
wherein each converter branch comprises an AC-to-DC stage and a DC-to-DC stage, which are connected between the first and second input and the first and second output;
wherein each AC-to-DC stage comprises a power factor corrector with a boost converter, which comprises at least two corrector branches each of which comprises an inductivity and a diode connected in series between an input and an output of the power factor corrector and a semiconductor switch connected between the inductivity and the diode on one side and to another input and output of the power factor corrector on another side;
wherein the converter system is configured for interconnecting the first input of each converter branch with a phase of a three-phase grid and for interconnecting the first input of the converter branches with a phase of a single-phase grid; and
wherein the converter system is configured for interconnecting the second inputs, which are interconnected with each other, of the converter branches with a neutral point of the three-phase grid or the single-phase grid;
wherein the converter system comprises one or more controllers adapted for controlling the converter branches independently from each other.
2. The converter system of claim 1 ,
wherein the one or more controllers are adapted for controlling the AC-to-DC stage and the DC-to-DC stage of a converter branch independently from the AC-to-DC stage and the DC-to-DC stage of another converter branch.
3. The converter system of claim 1 ,
wherein each AC-to-DC stage comprises a passive rectifier or active rectifier.
4. The converter system of claim 1 ,
wherein each AC-to-DC stage comprises an electrical filter connected to the first and second input.
5. The converter system according to according to claim 1 ,
wherein each AC-to-DC stage comprises an inrush current protector.
6. The converter system according to claim 1 ,
wherein each converter branch comprises a DC link, which is connected between the AC-to-DC stage and the DC-to-DC stage.
7. The converter system according to claim 1 ,
wherein the DC-to-DC converter comprises an isolated DC-to-DC converter.
8. The converter system according to claim 1 ,
wherein the DC-to-DC stage comprises an inverter, a transformer and a rectifier, which are cascade-connected.
9. The converter system according to claim 1 ,
wherein the DC-to-DC stages are connected in parallel at their outputs.
10. The converter system according to claim 1 ,
wherein the DC-to-DC converters are connected in series at their outputs.
11. The converter system according to claim 1 ,
wherein the one or more controllers are adapted for controlling the AC-to-DC stages independently from each other and/or the DC-to-DC stages; and/or
wherein the one or more controllers are adapted for controlling the DC-to-DC stages independently from each other and/or the AC-to-AC stages.
12. A battery charger for charging batteries comprising a converter system according to claim 1 .
13. The converter system of claim 2 , wherein each AC-to-DC stage comprises a passive rectifier or active rectifier.
14. The converter system of claim 2 , wherein each AC-to-DC stage comprises an electrical filter connected to the first and second input.
15. The converter system of claim 3 , wherein each AC-to-DC stage comprises an electrical filter connected to the first and second input.
16. The converter system according to according to claim 2 , wherein each AC-to-DC stage comprises an inrush current protector.
17. The converter system according to according to claim 3 , wherein each AC-to-DC stage comprises an inrush current protector.
18. The converter system according to according to claim 4 , wherein each AC-to-DC stage comprises an inrush current protector.