Vehicle-side charging device
Various embodiments of the teachings herein include a vehicle-side charging apparatus comprising: an AC voltage connection; a rectifier connected to the AC voltage connection; a first DC/DC converter and a second DC/DC converter; and a DC voltage connection. Each DC/DC converter includes a intermediate circuit capacitor and a switch unit. The rectifier is connected to the DC voltage connection via the DC/DC converters. There is a switch connecting the DC/DC converters in a switchable manner. In a first switching state the respective intermediate circuit capacitors and the respective switch units of the DC/DC converters are connected in parallel with one another and in a second switching state in series with one another. There is a third DC/DC converter connecting the rectifier to the DC voltage connection.
1. A vehicle-side charging apparatus comprising:
an AC voltage connection; a rectifier connected to the AC voltage connection;
a first DC/DC converter and a second DC/DC converter, each Dc/DC converter including a respective intermediate circuit capacitor and a respective switch unit;
a DC voltage connection; wherein the rectifier is connected to the DC voltage connection via the DC/DC converters;
a switch connecting the first DC/DC converter to the second DC/DC converter in a switchable manner, wherein the switch in a first switching state connects the respective intermediate circuit capacitors and the respective switch units of the first DC/DC converter and the second DC/DC converter in parallel with one another and in a second switching state connects the respective intermediate circuit capacitors and the respective switch units in series with one another; and a third DC/DC converter connecting the rectifier to the DC voltage connection.
2. The vehicle-side charging apparatus as claimed in claim 1 , wherein the first DC/DC converter, the second DC/DC converter, and the third DC/DC converter each have connections connected to the DC voltage connection and in parallel with one another.
3. The vehicle-side charging apparatus as claimed in claim 1 , wherein at least one of the first DC/DC converter and the second DC/DC converter comprises a DC-isolating DC/DC converter.
4. The vehicle-side charging apparatus as claimed in claim 1 , wherein the first DC/DC converter and the second DC/DC converter each comprise a buck-boost converter and the third DC/DC converter is designed either as a buck converter or a boost converter.
5. The vehicle-side charging apparatus as claimed in claim 1 , wherein the first DC/DC converter and the second DC/DC converters have essentially equal rated power.
6. The vehicle-side charging apparatus as claimed in claim 5 , wherein a rated power the third DC/DC converter is twice the rated power of the first DC/DC converter.
7. The vehicle-side charging apparatus as claimed in claim 1 , wherein the rectifier includes a boost function.
8. The vehicle-side charging apparatus as claimed in claim 1 , wherein the rectifier comprises an active power factor correction filter.
9. The vehicle-side charging apparatus as claimed in claim 1 , wherein the rectifier is programmed to rectify selectively in a three-phase or in a single-phase state.
10. The vehicle-side charging circuit as claimed in claim 1 , further comprising a controller with a low-power state or a low-voltage state to selectively activate only the first DC/DC converter, only the second DC/DC converter, both the first DC/DC converter and the second DC/DC converter, or only the third DC/DC converter, and a high-power state or a high-voltage voltage state to activate all of the first DC/DC converter, the second DC/DC converter, and the third DC/DC converter.
11. The vehicle-side charging circuit as claimed in claim 1 , wherein the third DC/DC converter comprises a switch unit; and
wherein the respective intermediate circuit capacitors of the first DC/DC converter and the second DC/DC converter are connected in parallel with the switch unit of the third DC/DC converter.