WO2013159821A1

WO2013159821A1 - Charging device

Info

Publication number: WO2013159821A1
Application number: PCT/EP2012/057743
Authority: WO
Inventors: Etienne Fogang Tchonla
Original assignee: Siemens Aktiengesellschaft
Priority date: 2012-04-27
Filing date: 2012-04-27
Publication date: 2013-10-31
Also published as: EP2810351A1

Abstract

The invention relates to a charging device (1) for electrically charging a traction battery (15) of an electric-drive vehicle (13), with a power supply terminal (3) for connecting the charging device (1) to an electrical energy source (7), a first charging terminal (9) and a second charging terminal (19) for connecting in each case one electric-drive vehicle (13, 23). A first converter unit (51) has a first AC terminal (50), a first AC/DC converter (52), a first DC intermediate circuit (54), a first DC/DC converter (56) and a first DC terminal (58). A second converter unit (71) has a second AC terminal (70), a second AC/DC converter (72), a second DC intermediate circuit (74), a second DC/DC converter (76) and a second DC terminal (78).

Description

The invention relates to a charging device for electrically charging a traction battery of an electrically driven vehicle and to a method for operating such a charging device. Electric powered vehicles are expected to play an important role in road traffic in the future. Such electrically driven vehicles have an electric traction battery, which provides electrical energy for the movement of the vehicle available. For charging such traction batteries there will be charging devices that are stationary (eg at a kind of charging station) instal ^¬ lated. Such charging devices can be configured as DC charging devices. These are charging devices that provide a DC charging current for charging the traction battery. Such charging devices can also be designed as AC charging devices. These are charging devices that provide a charging alternating current for charging the traction battery. The invention has for its object to provide a Ladeeinrich ^¬ tion and a method that can be used versatile for charging electrically powered vehicles.

This object is achieved by a charging device and a method according to the independent claims. Advantageous embodiments of the charging device and the method are specified in the dependent claims. The invention relates to a charging device for electrically charging a traction battery of an electrically driven vehicle with a power supply connection for connecting the charging device to an electrical energy source, a first and a second charging connection for connecting in each case an electrically drivable vehicle, a first converter unit which has a first AC connection, a first AC-DC converter, a first DC link, a first DC-DC converter and a first DC connection, and a second converter unit having a second AC terminal, a second AC-DC converter, a second DC link, a second DC-DC converter and a second DC connection.

In this case, it is particularly advantageous that the charging device has the first converter unit and the second converter unit. Thus, two vehicles can be loaded simultaneously. By means of such a converter unit, alternating current applied to the respective AC connection can be converted into direct current, which is output at the DC connection. The inverter unit then operates as a rectifier unit. Alternatively, such a drive unit can also in inverter operation processing ^¬ th, that is resting against the DC connection DC can be converted into alternating current, which is output at the JE weiligen AC connection. The Umrich ^¬ ter unit then operates as an inverter unit. With the first drive unit, a first electrically powered vehicle with electric power can be supplied to those who, while a second electrically powered vehicle can be supplied with electrical energy ^¬ simultaneously with the second converter unit. The charging device may also have further converter units, with which further electrically driven vehicles can be supplied with electrical energy to charge their traction batteries. But it is of course also possible, for. B. with the first inverter unit to charge a first electrically driven vehicle, while the second inverter unit not is used for charging an electrically driven vehicle.

The charging device may be configured so that the charging device has at least one further inverter unit on ^¬ which is similar to the first inverter unit or similar of the second inverter unit configured. In other words, the charging device can thus have two, three, four or more similar rectifier units. As a result, two, three, four or more electrically driven vehicles can be charged with this charging device at the same time.

The charging device may also be configured so that the first alternating-current terminal of the first inverter unit and the second alternating-current terminal of the second inverter A ^¬ uniform are respectively electrically connected to the power supply terminal, the first DC terminal is electrically connected to the first charging terminal and / or the second DC terminal is electrically connected to the second charging terminal.

The charging device can also be designed in such a way that the first converter unit has a first intermediate circuit connection, which is electrically connectable to the first DC intermediate circuit, and the second converter unit has a second intermediate circuit connection, which is electrically connected to the second direct-voltage connection DC link is connectable. By means of such a link connection can be engaged advanta- way legally energy in the DC link, that is, this direct-voltage intermediate circuit can be removed from electrical energy (subjected ent ^¬, rejects them) or it may be electrical energy introduced into the dc voltage intermediate circuit (fed initiates ) become. The charging device may also be configured so that the first intermediate circuit terminal is accessible from outside of the first Umrich ^¬ ter-unit and the second intermediate circuit terminal of the second inverter is outside the unit accessible lent.

The charging device may be configured so that the first drive unit has a first switching means for connecting the first DC voltage intermediate circuit electrically connected to the first intermediate circuit terminal and / or the second inverter unit includes a second switching device on ^¬ to the second DC -Zwischenkreis

verbin electrically connected to the second intermediate circuit terminal ^¬. By means of the switching device can advantageously the electrical connection between the respective

DC intermediate circuit and the respective intermediate circuit ^¬ circuit made or interrupted. With at ^¬ which words can be electrically insulated from the respective intermediate link connection or the respective DC intermediate circuit with the respective intermediate ^¬ link connection are electrically connected together by means of the switching device, the respective dc voltage intermediate circuit. This he ^¬ it enables to connect only at desired time intervals the respective DC intermediate circuit with the respective bus connection electric.

The charging device can also be configured such that the first intermediate circuit connection of the first converter unit and the second intermediate circuit connection of the second converter unit are electrically connected in parallel. As a result, the first DC link with the second

DC link electrically connectable. This electrical parallel connection of the intermediate circuit terminals he ^¬ it enables to connect the first DC voltage intermediate circuit electrically connected to the second direct voltage intermediate circuit (possibly with a corresponding switching position of the switching device or the switching means). This will be the first DC voltage intermediate circuit and the second

DC intermediate circuit brought to the same electric Po ^¬ potential or the first DC voltage intermediate circuit and the second DC voltage intermediate circuit have the same DC voltage occurring in the DC bus.

The charging device can also be configured such that at least one of the converter units has a voltage sensor and / or a current sensor in order to measure the DC voltage occurring in the DC voltage intermediate circuit and / or the DC current occurring in the DC intermediate circuit. With this voltage sensor, the size of the DC voltage occurring in the DC-DC ^{link is} he ^¬ mediates. The current sensor is used to determine the size of the direct current occurring in the respective DC voltage intermediate circuit. By linking the values of direct current and direct current, the electrical power currently transmitted by the intermediate circuit can be determined. The charging device can also be set up to first electrically connect the first DC voltage intermediate circuit to the second DC voltage intermediate circuit by means of the first switching device and / or by means of the second switching device, if the first DC intermediate circuit and the second DC voltage intermediate circuit have an equal DC voltage (DC link DC voltage). This advantageously ensures that no unwanted compensating currents flow when the two DC voltage intermediate circuits are electrically connected. This avoids the occurrence of unwanted power loss.

The charging means may also be constituted so that the charging means is arranged to transmit (as appropriate) electrical energy from the first DC voltage intermediate circuit of the ers ^¬ th inverter unit to the second direct-voltage intermediate circuit of the second inverter unit, or electrical energy from the second DC voltage intermediate circuit of the second converter unit to the first DC intermediate circuit of the first converter unit transmis ^¬ gene. This energy transfer takes place, for example, by DC transmission from the second DC link to the first DC link. Since ^¬ the first inverter unit of the second inverter unit with electrical energy provides comparable by, for example, in case of failure of the first alternating current ^¬-DC converter. As a result, the first converter unit can continue to provide a direct current at the first DC connection in this case as well.

The charging device may also (remote ladeeinrichtungsin- or charging means external) an electrical energy storage comprise (for example a battery or a capacitor, in particular a super capacitor), which at least temporarily to the DC voltage intermediate circuit Minim ^¬ least one of the converter units can be connected (by

transfer electrical energy from the energy store to the DC link (s)). By means of this energy storage device, the function of the charging device can also be maintained at least for a limited time if one Kompo ^¬ component of the charging device or in a temporary power failure by electric energy is transferred from the energy storage to the respective DC bus or DC bus. The charging device can also be designed so that the AC power connection, the DC power connection and / or the DC link connection of at least one (ie one or more or all) of the inverter units are made pluggable. This makes it possible to remove the converter units in a simple manner from the charging device or to insert them into the charging device as required (eg in the case of a defect or during maintenance work). In particular, the charging device can be designed such that at least one of the converter units is designed as a plug-in unit which can be inserted into a housing of the charging device and pulled out of the housing.

The charging device can also be configured such that in the first converter unit, the first AC-DC converter has a smaller maximum converter power than the first DC-DC converter

and / or in the second inverter unit, the second Wech ^¬ selstrom-DC converter having a smaller maximum inverter power than the second DC-DC converter. Namely, it is advantageous that by the possible transmission of electrical power from one of the DC bus to another of the

DC intermediate circuits of the AC-DC converter of a converter unit may be smaller than the corresponding DC-DC converter of this inverter unit. The electrical power that can not be supplied by the AC-DC converter is then transmitted directly from another converter unit to the DC link and fed into it.

The invention further provides a method for operating a charging device for electrically charging a traction battery of an electrically driven vehicle with a power supply terminal for connecting the Ladeein ^¬ direction to an electrical energy source, a first and a second charging port for connecting each of an electrically driven vehicle, a first inverter A unit having a first AC terminal, a first AC-DC inverter, a first DC link, a first DC-DC converter and a first DC terminal, and a second inverter unit, comprising a second alternating current terminal, a second AC-DC converter, a second DC voltage intermediate circuit, a second DC-DC converter and a second DC terminal, in which method at ^¬ least temporarily electrical energy is transferred from the first DC clamping ^¬-voltage intermediate circuit the first converter unit to the two ^¬ th DC voltage intermediate circuit of the second inverter A ^¬ uniform or at least at times, electric power from the second DC-voltage intermediate circuit of the second inverter unit to the first DC Intermediate circuit of the first inverter unit is transmitted.

This method can be designed so that

electrical energy is transmitted from the first DC link to the second DC link when the required at the second DC terminal electrical energy is not provided by the second AC-DC converter or then electrical see energy from the second DC link to the first DC link is transmitted when needed at the first DC connection

electrical energy can not be provided by the first AC-DC converter.

As already mentioned above, the first converter unit and / or the second converter unit (and also given ^¬ if further existing converter units) may each be a rectifier unit.

The method also has the advantages indicated above in connection with the charging device.

The invention will be explained in more detail below with reference to an exemplary embodiment. This is in Figure 1 is a schematic representation of an Ausführungsbei ^¬ game of a charging device with connected vehicles, in Figure 2 is an exemplary illustration of a converter unit and in

Figure 3 shows a schematically illustrated embodiment of a charging device with a housing shown in sectional representation.

In Figure 1, a charging device 1 is shown, which is designed in the embodiment as a DC charging device ^¬ . The charging device 1 has a power supply connection 3 in order to electrically connect the charging device 1 to an electrical energy source 7. The energy source 7 is configured here as an energy supply network 7. The power supply terminal 3 is electrically connected to the power supply network 7 by means of a three-wire connection cable 5.

Furthermore, the charging device 1 has a first charging connection 9, which can be electrically connected to a first electrically drivable vehicle 13 by means of a first charging cable 11. The electrically drivable vehicle 13 has a first drive battery 15 which can be charged by means of the Ladeeinrich ^¬ device 1. Furthermore, the device 1 loading units to a second charging terminal 19, to which by means of a charging cable 21, a second electrically powered driving ^¬ generating connectable 23rd This second electrically drivable ^¬ bare vehicle 23 has a second traction battery 25, which is chargeable by means of the charging device. In addition, the charging device 1 has a third charging connection 29, which is electrically connectable by means of a charging cable 31 to a third electrically driven vehicle 33. This third electrically drivable vehicle 33 has a third drive battery 35. Likewise, the charging device 1 has a fourth charging connection 39, which is electrically connectable by means of a fourth charging ^¬ cable 41 with a fourth electrically driven vehicle 43. By means of this fourth charging connection 39, the fourth drive battery 45 of the fourth electrically drivable vehicle 43 can be charged. The first charging port 9, the second charging port 19 and the third charging port 29 and the fourth charging port 39 are each electrically isolated. Different output voltages and output ^currents can be output at these charging connections.

The power supply connection 3 is electrically connected to a first AC connection 50 of a first converter unit 51 by means of a cable 47 inside the charging device 47 (connection cable 47). Via the first AC terminal 50, AC power provided from the power grid 7 is supplied to the first AC-DC converter 52 which converts (converts) the AC power into DC power. This DC current passes to a first DC link 54, which electrically connects the first AC-DC converter 52 (AC / DC converter) to a first DC-DC converter 56 (DC / DC converter). The first DC-DC converter 56 has a potential separation, which is symbolized by the two parallel diagonal lines. This first DC-DC converter 56 converts the direct current from the intermediate circuit 54 into a DC voltage of a different voltage and / or different current, which is then output at a first DC connection 58 of the first converter unit 51. This first DC connection 58 is electrically connected to the first charging connection 9 of the charging device 1. The first converter unit 51 is therefore designed as a first rectifier unit 51 in the exemplary embodiment. This first inverter unit 1 directs the one to the first AC terminal 50 input AC current and generates a DC output at the first DC port 58. The first DC intermediate circuit 54 is electrically connected to a first DC link control 60. This DC link controller 60 is, inter alia, able to electrically connect the first DC voltage intermediate circuit 54 to a first DC link connection 62 (a so-called DC power link connector). For this purpose, the first intermediate circuit control 60 has a first switching device 63, which is shown in more detail in FIG. By means of the first switching device 63, the energy stored in the first DC voltage intermediate circuit 54 can be output at the first intermediate circuit connection 62.

Furthermore, the charging device 1 has a second converter unit 71. This second converter unit 71 has a second AC connection 70, a second AC / DC converter 72, a second DC intermediate circuit 74, a second DC / DC converter 76, a second DC connection 78, a second intermediate circuit controller 80 and a second DC link connection 82 on. The second DC link controller 80 has a second switching device 81. Furthermore, the La ^¬ signaling device 1 in a similar third inverter unit 91st This third inverter unit 91 has a third alternating-current terminal 90, a third AC-DC converter 92, a third DC-voltage intermediate circuit 94, a third DC-DC converter 96, a third direct current terminal 98, a third intermediate ^¬ circuit controller 99 and a third intermediate circuit terminal 102. The third DC link control 99 has a third switching device 97. In addition, the charging device 1 has a fourth converter unit 101. This fourth converter unit 101 has a fourth AC adapter ^¬ 100, a fourth AC DC Inverter 102, a fourth DC intermediate circuit 104, a fourth DC-DC converter 106, a fourth DC connection 108, a fourth intermediate ^¬ circle controller 110 and a fourth DC link 112 on. The fourth DC link controller 110 also has a fourth switching device 113.

The second direct current terminal 78 is electrically connected to the second charging terminal 19, the third direct current terminal 98 is electrically connected to the third charging terminal 29 and the fourth direct current terminal 108 is electrically connected to the fourth charging terminal 39.

Furthermore, the first alternating current connection 50, the second alternating current connection 70, the third alternating current connection 90 and the fourth alternating current connection 100 are electrically connected by means of the cable 47 to the energy supply connection 3 and thus to the energy supply network 7. Here, in the embodiment, the first AC terminal 50, the second AC power connector 70, the third Wechselstroman ^¬ circuit 90 and the fourth AC power connector 100

electrically connected in parallel.

Furthermore, the first intermediate circuit terminal 62 is electrically ver ^¬ connected to the second intermediate circuit terminal 82, the third intermediate circuit ^¬ terminal 102 and the fourth intermediate circuit terminal 112 by means of an intermediate circuit connecting cable 114th By means of the DC link connections, that is, the DC intermediate circuits inverter-external (ie outside the inverter units) can be electrically connected to each other. By means of the intermediate circuit connecting cable 114, the first intermediate circuit terminal 62, the second interim ^¬ intermediate circuit terminal 82, the third DC terminal 102 and the fourth intermediate circuit terminal 112 are electrically connected in parallel. The first intermediate circuit control 60 of the first converter unit 51 has the first switching device 63 (see FIG. 2), by means of which the first DC intermediate circuit 54 can be electrically connected to the first intermediate circuit connection 62 if required. The first intermediate circuit terminal 62 is outside of the first inverter unit 51 ENTRANCE ^¬ Lich, consequently (with appropriate switching position said first switching means 63, namely at the closed switches of the switching device 63) of the first DC-voltage intermediate circuit 54 of the first inverter unit 51 leads ^¬ out and accessible at the first ^{DC link} 62. Similarly, in the case of the second converter unit 71, the third converter unit 91 and the fourth converter unit 101, the respective DC intermediate circuit is switched out to the respective DC link terminal 82, 102 and 112, respectively.

The respective intermediate circuit terminals 62, 82, 102 and 112 are electrically connected in parallel. As a result (for closed switching position of the first switching device 63 and the respective switching devices of the other inverter units) z. B. the first DC-DC link 54 to the second DC-DC link 74 electrically connected.

Furthermore, an electrical energy store 116 (for example a battery or a high-power capacitor) is electrically connected in parallel with the intermediate circuit terminals 62, 82, 102 and 112. In the exemplary embodiment, the energy store 116 is arranged within the charging device 1, so it is a charging device internal energy storage. In another embodiment, however, this energy storage device 116 may also be arranged outside the charging device 1 and be electrically connected thereto; it is then a charging device external energy storage. The energy storage unit 116 is optional and may be omitted in other Ausführungsbei ^¬ play. It can supply electrical energy from the energy storage 116 via the DC link cable 114 to the first

DC intermediate circuit 54, the second DC voltage intermediate circuit 74, the third DC voltage intermediate circuit 94 and / or to the fourth DC intermediate circuit 104 are transmitted to the electrical energy in this DC intermediate circuit or in this

Feed in DC intermediate circuits. The giespeicher in the energy 116 stored energy can be fed (at ^¬ play, in a failure of an AC-DC inverter or a complete inverter unit) via the intermediate circuit connecting cable 114 into one or more DC voltage intermediate circuit as needed to to continue operating the charging device 1 for a short time.

In Figure 2, the first drive unit is shown in detaillier ^¬ more excellent shape 51st In addition to the first switching device 63 already mentioned, the first converter unit 51 has a first voltage sensor 202 and optionally also a first current sensor 204. The first voltage sensor 202 measures the DC voltage occurring in the DC link 54

DC voltage (DC link DC voltage); the first

Current sensor 204 measures the DC current (DC-DC) occurring in the first DC link 54.

Furthermore, the first converter unit 51 has a first AC-side protection circuit 208 and a first AC-side filter 210. The first wechselstromsei ^¬ term protection circuit 208 serves to protect the first electric drive unit 51 at the AC terminal 50. This protection circuit 208 realizes an overvoltage protection and / or overcurrent protection; For example, it contains a backup. The first AC-side filter 210 filters resulting in the first inverter unit 51 electromagnetic interference and ensures that these electromagnetic interference does not reach the first AC power connection 50. Furthermore, the first converter unit 51 has a first DC-side filter 212 and a first DC-side protective circuit 216. The first DC-side filter 212 filters out electromagnetic interference from that of the first inverter unit 51 are formed in ^¬ nerhalb, and prevents that these disturbances reach the first circuit Gleichstroman- 58th The first DC-side protection ^¬ circuit 216 realizes a DC-connection-side voltage and / or over-current protection. For example, a fuse may be incorporated in the protection circuit 216. Further, this protection circuit 216 may optionally include a power diode (for preventing the flow of

DC in the wrong direction) or this protection circuit 216 may optionally include a reactor (for smoothing the DC current flowing to the DC terminal).

The first AC side protection circuit 208, the first AC-DC converter 52, the first DC link controller 60, the first DC-DC converter 56 and the first DC side protection circuit 216 are connected to a first controller 222 of the inverter unit 51 via communication lines 220, respectively , This Umrichtereinheits-controller 222 has a first Datenan- circuit 224, the forth is executed ^¬ from the first inverter unit 51 and with a higher-level control 320 (see FIG. FIG. 3) is connected to the charging device 1. Among other things, the first controller 222 retrieves information and data from said assemblies of the first inverter unit 51, forwards this information and data to the higher-level controller 320, receives instructions from the higher-level controller 320, and forwards these instructions or instructions. Commands to the modules of the first inverter unit 51 on. The first alternating current connection 50, the first direct current connection 58, the first intermediate circuit connection 62 and the first data connection 224 of the first converter unit 51 are made pluggable. Therefore, these terminals can be quickly and easily electrically disconnected or electrically connected.

In the embodiment, the first inverter unit 51, the second inverter unit 71, the third drive unit 91 and the fourth inverter unit 101 are similarly formed from ^¬ or designed. In particular, all ^these converter units contain a switching device, a voltage sensor and a current sensor similar to the first converter unit 51.

3 shows in a schematic sectional view of the basic mechanical and electrical structure of the Ladeein ^¬ device 1 is shown.

The charging device 1 has a housing 302, which stands on housing feet 304. The power supply terminal 3, the first charging terminal 9, the second charging terminal 19, the third charging terminal 29, the fourth charging port 39 and a Datenan ^¬ circuit 308 are arranged on a rear side 306 of the housing 302 and is accessible from outside of the charging device. 1 The first inverter unit 51, the second order ^¬ judge unit 71, the third drive unit 91 and the fourth inverter unit 101 are each configured as Einschubeinhei- th, and out inserted into the housing 302 of the charging device 1 to the housing 302 are pulled out. For this purpose, 310 openings are provided in a front side, which can be closed with flaps or the like (not shown in the figure). In the first converter unit 51 (and also in the other converter units 71, 91 and 101) is shown schematically that the first data terminal 224, the first AC terminal 50, the first intermediate Circuit 62 and the first DC power jack 58 are designed pluggable. A movable (inverter unit side) part of these terminals is arranged on the first inverter unit, while a stationary (housing-side) part of these terminals is arranged on a mounting wall 314 of the charging device. By means of a handle 316, the first converter unit 51 from the housing 302 of the Ladeein ^¬ direction 1 can be pulled out or inserted into this housing. Similarly, the second, third and fourth converter unit 71, 91 and 101 are configured. The Um ^¬ judge units each represent a module (inverter module); the charging device has a modular construction.

Furthermore, the charging device 1 has a controller 320, which is configured as a higher-level controller for the controller 222 of the first converter unit and for the controllers of the other converter units. This charger control 320 is also designed as a plug-in unit, which can be inserted into the housing 302 or pulled out of the housing. However, the charger controller 320 may also be fixedly mounted in the housing 302.

Furthermore, the charging device 1 has an input circuit 324, an output circuit 328 and a data unit 332. The input circuit 324 (input stage) has a main switch for the entire charging device. The output circuit 328 has output filters of the charger. Monitoring and signaling devices may also be arranged in the input circuit and the output circuit. The data unit 332 is used for buffering data that can be output via the data terminal 308. By solid lines (solid lines) are shown in Figure 3, the cables 47, which are the AC terminals 50, 70, 90 and 100 of the four inverter units and a AC terminal 323 of the controller 320 via the input ^¬ circuit 324 electrically connect to the power supply terminal 3 (AC connection cable 47). With ^¬ means of dashed lines Data cables 336 are shown, which the first data terminal 224 of the first inverter unit 51 with a second data port 340 of the second inverter unit 71, a third data port 342 of the third inverter unit 91, a fourth data port 344 of the fourth inverter Unit 101 and a data terminal 348 of

Connect controller 320 electrically. These data connections are made by means of the data cable 336 with the data unit 332 and with the data connection 308 of the charging device 1

electrically connected. By means of dot-dash lines, the intermediate circuit connecting cables 114 are shown, which electrically connect the intermediate ^circuit terminals 62, 82, 102 and 112 of the four converter units 51, 71, 91 and 101 with each other. By dotted lines DC cables 350 are shown, which the first DC connection 58, the second

DC connection 78, a third DC connection 352 and a fourth DC connection 354 of the converter units via the output circuit 328 electrically connect to the respective associated charging port.

The mode of operation of the charging device 1 will be explained in more detail below with reference to FIG. 1 using the example of the first converter unit 51. In the embodiment the Ladeein ^¬ device operates as a DC charging device, that this charging device converts the information provided by the power supply mains 7 AC power to DC power and transmits electric energy in the form of direct current to the attached ^¬ closed electrically driven vehicles. Accordingly, in the embodiment, the first inverter unit 51 is configured as a first rectifier unit, or operates as such a first rectifier unit. Also, the second, third and fourth inverter units 71, 91 and 101 operate in each case as a second, third and fourth rectifier A ^¬ unit.

First, the first switching device 63 of the first converter unit 51 is opened (the switching state shown in FIG. 2 is therefore present). This is the first one

DC link 54 from the first intermediate circuit terminal 62 and the DC link connecting cable 114 electrically isolated.

In this operating mode, electrical energy in the form of alternating current flows from the power supply network 7 via the connecting cable 5, the power supply connection 3, the cable 47 and the first AC connection 50 (first AC input 50) to the first AC-DC converter 52. The first AC-to-DC converter 52 converts this alternating current into direct current, which is conducted into the first DC intermediate circuit 54. At the dc output of the first AC-to-DC rectifier 52 environmental electric capacitors (so-called interim ^¬ intermediate circuit capacitors) are arranged for storing electrical energy. The electric energy is transmitted to the ers ^¬ th DC-DC converter 56, which converts the derived from the intermediate circuit DC power in DC Ström different voltage and / or other current and to the first DC terminal 58 (first DC ^¬ current output 58 ). Thereupon, this DC current passes as a charging current via the first charging connection 9 and the first charging cable 11 to the first electrically driven vehicle 13 in order to charge its first driving battery 15. In this mode, the first converter unit can indepen ^¬ gig working from the other inverter units and independently supply the first electric automobile 13 with direct current. The occurring current flow or energy flow is shown in FIG. 2 by means of arrows 230. However, it may be the case that an electric power required by the first electrically drivable vehicle 13 at the first charging terminal 9 is so large that it can not be provided by the first AC-DC converter 52 , This is particularly apparent when one considers that can transmit a maximum electrical output of 50 kW in Ausführungsbei ^¬ play the first DC-DC converter 56, while the first AC-DC converter 52 QUIRES ONLY borrowed a maximum electrical output of 25 kW can transmit. So if the vehicle 13 requests a power of 40 kW at the first charging port 9, so the first

DC-DC Inverters 56 transmit this power. However, the first AC-to-DC converter 52 can not transmit this electric power, namely, this can only a maximum of 25 kW in the first performance

Feed in DC intermediate circuit 54. Therefore, in this case, electric power from an intermediate circuit of another inverter unit additionally becomes the first one

DC intermediate circuit 54 is fed.

In the embodiment, the electric power for loading ^¬ riding provide the missing 15 kW power from the second DC voltage intermediate circuit 74 is to transmit to the first direct voltage intermediate circuit 54 and fed into the latter. For this purpose, the direct voltage that occurs in the first DC intermediate ^circuit 54 is first measured by means of the first voltage ^sensor 202 and the measured values are transmitted via the first controller 222 to the higher-level control 320 of the charging device. Such a voltage measurement also takes place in the second DC voltage intermediate circuit. The voltage value measured there also becomes the

Control 320 transmitted. The controller 320 then controls the first AC-DC converter 52 and the first DC-DC converter 56 via the converter-unit-internal controller 222 in such a way that a defined DC voltage (in the DC intermediate circuit 54) example, 600 V) is set. In the same way, the controller 320 ensures that also in the second DC voltage intermediate circuit 74, this DC voltage of 600 V is set. Only when the DC voltage of the first DC intermediate circuit 54 is equal to the DC voltage of the second DC intermediate circuit 74, the first switching device 63 of the first inverter unit 51 and the corresponding switching device of the second converter unit 71 is closed. This will be the first

DC voltage intermediate circuit 54 and the second DC-voltage intermediate circuit chip ^¬ 74 electrically connected in parallel. Through the parallel connection of the DC intermediate circuits ^¬ to the AC-DC converter electrically connected in parallel. By switching only when identical

DC voltages ensures that no unerwünsch ^¬ th high equalizing currents flow and no undesirable power losses when interconnecting the two

DC intermediate circuits occur. Then, DC power is transferred from the second DC link 74 to the first DC link 54 by DC power and thus provided to the first DC-DC converter 56. Then, this DC-DC converter 56 can provide the requested power of 40 kW at the first charging terminal 9 (25 kW power is supplied from the first AC-DC converter 52, the power for providing the missing 15 kW power are provided by the second AC-DC converter 72). The be ^¬ riding Asked electric in the first DC-DC 54 power is thus controlled by the participating AC-DC converters 52 and 72 to feed only the amount of energy in the DC link circuit 54, which is currently needed in the DC intermediate circuit. As a result, the charging device 1 is very energy efficient. The additionally occurring current flow or Energy flow is shown in Figure 2 by means of additional arrows 235.

In this way, of course, electrical energy can also be transmitted from the first DC link 54 to the second DC link 54 when a large electrical power is required at the second charging port 78. A similar sequence can also take place with the involvement of the third converter unit 91 or the fourth converter unit 101.

In the exemplary embodiment, the AC-DC converters 72, 92 and 102 can each transmit a maximum electric power of 25 kW, whereas the DC-DC converters 76, 96 and 106 can transmit a maximum electric power of 50 kW. Because of the potential power output of 50 kW, this charger can be used, for example for CHAdeMO kompa ^¬ tible applications.

The individual converter units 51, 71, 91 and 101 thus each represent independent modules and each have an outwardly guided DC voltage intermediate circuit. In this case, this DC-DC link is guided in each case as a DC link connected controlled to the outside, ie by means of the switching device, the DC-DC link with the DC link electrically connected ^¬ or the DC link can from the

DC link are electrically isolated. By means of the intermediate circuit connections, the DC voltage intermediate circuits of the individual converter units outside the converter units can be electrically connected to one another as required. In a further example, a transfer of energy from the second DC voltage link 74 to the first DC link 54 may also be useful, if only low powers are requested at the first charging connection 9 and the second charging connection 19, for example only 10 kW in each case. Then, the required energy from ^¬ can be finally provided by the second AC-DC Umrich- ter 72; the first AC-DC converter 52 remains switched off (eg in standby mode). As a result, the second AC-DC converter 72 is better utilized at 20 kW power than at 10 kW, so it operates at a favorable operating point and thus energy-efficiently.

It may also be measured by the first current sensor 204

Current values are transmitted via the first controller 222 to the superordinate controller 320 of the charging device. By means of the voltage values and / or current values present at the higher-level controller 320, the voltage values and / or current values present in the higher-level controller 320 can then be determined

DC bus stored energy is detected and monitored. The structure of the charging device 1 from individual converter units has a number of advantages. Only those inverter units that are currently being used need to be switched on. The other inverter units can be switched off (eg put into standby mode). In particular, the AC-DC converters are activated only when existing power requirements and remain otherwise in standby mode (standby mode). Likewise, the DC-DC converters are only activated when the respective associated charging port is actually borrowed used for charging a vehicle. This results in low power dissipation and high efficiency more ^energy-¬ the charging device; a good efficiency of the charging device 1 is achieved. When defects occur, a single inverter unit can be quickly and inexpensively replaced by this designed as a module inverter unit a functioning inverter unit is replaced. This results in a high availability of the charging device. Wei ^¬ terhin it is possible to drive all four units (or any other number of inverter units of the charger) perform similar or even identical. Nevertheless, (in particular by the case-by-case interconnection of the DC intermediate circuits of the individual converter units) a wide variety of outputs can be made available at the charging connections. Therefore, it is only necessary to develop, produce and stock a single type of inverter unit, which is cost-effective.

It has been described a charging device and a method for operating the charging device, which make it possible to aufzula ^¬ in a cost-effective and energy-efficient manner meh ^¬ rere electrically driven vehicles simultaneously. Due to the use of modular converter units results in a versatile charging device that can be realized and operated inexpensively.

Claims

claims

1. Loading device (1) with (15) of an electrically driven vehicle (13) to electrically charge a driving battery - a power supply terminal (3) for connecting the La ^¬ signaling device (1) to an electrical energy source (7),

- a first charging port (9) and a second charging port (19) for connection of an electrically drivable ^¬ cash vehicle (13, 23),

a first converter unit (51) having a first AC connection (50), a first AC-DC converter (52), a first DC intermediate circuit (54), a first DC-DC converter ( 56) and a first DC connection (58), and - a second converter unit (71) having a second AC connection (70), a second AC-DC converter (72), a second DC link (74), a second DC-DC converter (76) and a second DC connection (78) has up.

2. Loading device according to claim 1,

d a d u r c h e c e n c i n e s that

- The charging device has at least one further converter unit (91, 101), which is similar to the first Umrich ^¬ ter unit (51) or the second converter unit (71) designed from ^¬ .

3. charging device according to claim 1 or 2,

d a d u r c h e c e n c i n e s that

- The first AC terminal (50) of the first inverter unit (51) and the second AC terminal (70) of the second inverter unit (71) are each electrically connected to the power supply terminal (3), the first DC terminal (58) electrically connected to the first charging area ^¬ circuit (9) and / or the second Gleichstroman- circuit (78) is electrically connected to the second charging port (19).

4. Charging device according to one of the preceding claims, d a d u r c h e c e n e c i n e that t

- The first converter unit (51) has a first intermediate circuit connection (62) which is electrically connectable to the first DC intermediate circuit (54) and

- The second converter unit (71) has a second intermediate circuit terminal (82) electrically connected to the second

DC intermediate circuit (74) is connectable.

5. Charging device according to one of the preceding claims, characterized in that a

- The first intermediate circuit terminal (62) from outside the first inverter unit (51) is accessible and the second intermediate circuit terminal (82) from outside the second Umrich ^¬ ter unit (71) is accessible.

6. Charging device according to one of the preceding claims, characterized in that a

- The first converter unit (51) has a first Schalteinrich ^¬ device (63) to electrically connect the first DC voltage intermediate circuit (54) with the first intermediate circuit terminal (62) and / or

- The second converter unit (71) has a second Schaltein ^¬ direction (81) to electrically connect the second DC voltage intermediate circuit (74) with the second intermediate circuit terminal (82).

7. Charging device according to one of the preceding claims, characterized in that a

- The first intermediate circuit terminal (62) of the first converter unit (51) and the second intermediate circuit terminal (82) of the second converter unit (71) are electrically connected in parallel.

8. Charging device according to one of the preceding claims, d a d u r c h e c e n e c i n e that t

- At least one of the converter units (51) has a voltage sensor (202) and / or a current sensor (204) to those in the DC intermediate circuit (54) occurring

DC voltage and / or the direct current in the DC intermediate circuit (54) to be measured.

9. Loading device according to one of claims 6 to 8,

d a d u r c h e c e n c i n e s that

- The charging device (1) is set up, only then by means of the first switching device (63) and / or the second

Switching device (81) to electrically connect the first DC link (54) to the second DC link (74) when the first DC link (54) and the second DC link (74) have a DC voltage of equal magnitude.

10. A charging device according to one of the preceding claims, characterized in that a

- the loading device (1) is arranged to transmit or electrical Ener ^¬ energy from the first DC voltage intermediate circuit (54) of the first inverter unit (51) to the second DC link (74) of the second inverter unit (71) electrical energy from the second

DC voltage intermediate circuit (74) of the second inverter ^¬ A unit (71) to be transmitted to the first direct voltage intermediate circuit (54) of the first inverter unit (51).

11. Charging device according to one of the preceding claims, d a d u r c h e c e n e z e c h e n e, that

- An energy store (116) which is at least temporarily electrically connectable to the DC intermediate circuit (54) at least one (51) of the converter units.

12. Loading device according to one of the preceding claims, characterized in that - The AC power connection (50), the DC power connection (58) and / or the intermediate circuit connection (62) of at least one (51) of the converter units are designed pluggable.

13. Charging device according to one of the preceding claims, d a d u r c h e c e n e c i n e that t

- At least one of the inverter units as a drawer ^¬ unit (51) is configured, which in a housing (302) of the charging device (1) can be inserted and pulled out of the housing (302).

14. Charging device according to one of the preceding claims, characterized in that a

in the first converter unit, the first AC / DC converter has a smaller maximum converter power than the first DC / DC converter and / or

- In the second converter unit (71) of the second ^{AC ¬} current-DC converter (72) has a smaller maximum inverter power than the second DC-DC inverter (76).

15. A method for operating a charging device (1) for electrically charging a traction battery (15) of an electrically driven vehicle (13)

- a power supply terminal (3) for connecting the La ^¬ signaling device (1) to an electrical energy source (7),

a first charging connection (9) and a second charging connection (19) for connecting in each case one electrically drivable vehicle (13, 23),

a first converter unit (51) having a first AC terminal (50), a first AC-DC converter (52), a first DC intermediate circuit (54), a first DC-DC converter (56) and a first DC connection (58), and

a second inverter unit (71) having a second AC terminal (70), a second AC terminal DC converter (72), a second DC link (74), a second DC-DC converter (76) and a second DC connection (78) on ^¬ points,

d a d u r c h e c e n c i n e s that

- At least temporarily electrical energy from the first DC voltage intermediate circuit (54) of the first inverter unit ^{¬ unit} (51) to the second DC voltage intermediate circuit (74) of the second inverter unit (71) is transmitted or

- At least temporarily electrical energy from the second

DC voltage intermediate circuit (74) of the second inverter ^¬ A unit (71) to the first direct voltage intermediate circuit (54) of the first inverter unit (51) is transmitted.

16. The method according to claim 15,

d a d u r c h e c e n c i n e s that

- Then electrical energy from the first DC link (54) is transmitted to the second DC link (74) when the required at the second DC power connection (78) electrical energy is not from the second AC-DC converter (72 ) is ready or

- Then electrical energy from the second DC link (74) is transmitted to the first DC intermediate circuit (54) when the at the first DC terminal (58) required electrical energy is not from the first AC-DC converter (52 ) is available.