WO2013104410A1

WO2013104410A1 - Method for operating a charging device for charging a traction battery

Info

Publication number: WO2013104410A1
Application number: PCT/EP2012/050238
Authority: WO
Inventors: Etienne Fogang Tchonla
Original assignee: Siemens Aktiengesellschaft
Priority date: 2012-01-09
Filing date: 2012-01-09
Publication date: 2013-07-18

Abstract

The invention relates to a method for operating a charging device (1) for electrically charging a traction battery (3) in an electrically drivable vehicle (5). Said charging device (1) includes a mains terminal (27) for connecting the charging device to a power supply system (29), at least one charging terminal (43) for connecting an electrically drivable vehicle (5) and a plurality of electric converters (7, 9, 11, 13, 15, 17, 19, 21), the inputs (23) of which are electrically connected to the mains terminal (27) and the outputs (31) of which are electrically connected to an intermediate circuit (33) of the charging device. In said method, the output voltages of at least two of the converters (7, 9) are adjusted to a common desired value.

Description

description

METHOD FOR OPERATING A LOADING DEVICE FOR LOADING

A driving battery The invention relates to a method for operating a La ^¬ signaling device for electrically charging a traction battery of an electrically driven vehicle, and such a loading ^¬ device. Electrically driven vehicles will be used in the future

Road traffic increasingly play an important role. Electrically driven vehicles have an electric traction battery, which provides electrical energy for the Fortbewe ^¬ tion of the vehicle. For charging such traction batteries, there will be charging devices that are stationary

(eg at a kind of charging station, at car rents or parking garages) are installed. Such chargers be Kings ^¬ nen designed as direct current charging devices. These are charging devices that provide a DC charging current for charging the traction battery. Such Ladeeinrich ^¬ lines can also be configured as AC charging devices. These are charging devices that provide a charging alternating current for charging the traction battery.

To charge batteries quickly driving, charging equipment are needed that can provide high electrical power to charge ready ^¬.

The invention has for its object to provide a method and a charging device, which allow efficient charging.

This object is achieved by a method and a charging device according to the independent patent claims ^¬ chen. Advantageous embodiments of the method and the La ^¬ deeinrichtung are specified in the dependent claims. Is given According to the invention a method for operating a charging device for electrically charging a Fahrbatte ^¬ rie of an electrically driven vehicle, the charging ^¬ device dean-circuit a mains connection for connection of the Ladeein ^¬ direction to a power supply network, at least one laser for connecting an electrically powered driving ^¬ zeugs, and a plurality of electrical converters whose inputs are electrically connected to the power supply and whose outputs are electrically connected to a DC link of the charging device ^¬ has. In this case, the line-side converters can each be individually connectable or disconnectable. In the method, the output voltages of at least two of the inverters are set to a common setpoint. It is advantageous that flow due to the identical output voltages between the outputs of these converters no compensation currents. Thus, the emergence of power loss is minimized and the Ladeein ^¬ direction is energy efficient and with a large We ^¬ ciency.

The method may be configured such that the setpoint is transmitted from one of the inverters, which operates as a master, to at least one of the other inverters of the plurality, which operates as a slave. This sicherge ^¬ assumed that the inverters are always informed about the current set point for the output voltages.

The method can proceed in such a way that, after the desired value has been received by the at least one converter operating as a slave, its output voltage is set to the desired value.

The process may also proceed so that the inverter of the plurality during operation of the charging device in depen ^¬ dependence of demand for electrical charging power a respective are ^¬ individually switched on or switched off, wherein before or during the switching on of one of the inverter whose output clamping ^¬ voltage on the Setpoint is set. This makes it possible adapt the charger to a change in demand for electrical ^¬ shear loading performance. In a small required charging electric power only one or a few ^¬ To judge the majority needs to be switched on while other inverters of the plurality added for a large required charging electric power.

The method can proceed so that a control of the charging means divides the working as the master inverter mitge ^¬ is, to which operating as a slave inverter, the setpoint is to be sent.

The method can also be configured such that the are Umri- cher AC-DC converter and the interim ^¬ intermediate circuit a DC intermediate circuit.

Is given according to the invention further comprises a charging means for electrically charging a traction battery of an electrically driven vehicle with a power connector for connecting the charging device to a power supply network, at least one load connection for connecting an electrically antreibba ^¬ ren vehicle, a plurality of electric inverters having their inputs electrically connected to the power supply are connected and whose outputs are electrically connected to an intermediate circuit of the charging device, wherein at least two of the inverters are adapted to set their output voltages to a common setpoint. Thus, all inverters can also be set up to set their output voltages to a common setpoint.

This charging device can be designed so that one of the inverter is set up as a master which transmits set ^¬ worth to the other inverter and the other inverters can be set up as slaves.

The charging device may also be configured so that the inverter of the plurality (depending on the demand for electrical charging power ^¬ example, during operation of the charging device ^¬) are each connected individually switched on or off, and that the inverters are set to adjust their output voltage to the setpoint before or during connection.

The charging device can also have a controller which is set up to inform the converter operating as a master of which converter the slave setpoint is to be sent to.

The charging device can also be designed such that the recorders are AC-DC converters and the DC link is a DC intermediate circuit.

The charging device can also be realized in such a way that a reactive current compensation unit of the converter is set up as master or as slave.

Furthermore, the charging device can have at least one charging connection-side converter whose input is connected to the intermediate circuit and whose output is connected to the charging connection.

In the following the invention on the basis ^of an exemplary ^embodiment is explained in detail. This is in the

Figure is a representation of an embodiment of the

Charging device and the method shown.

In the figure, a charging device 1 for electrically charging a traction battery 3 of an electrically driven vehicle 5 is shown. In the exemplary embodiment, this charging ^¬ device is configured as a DC charging device 1. However, this charger can also be configured as an AC charger that provides the charging area ^¬-circuits a charging AC to charge the traction battery. _r

5

The DC charging device 1 has a first network connection side converter 7, which is formed in the embodiment as an AC-DC converter (AC / DC converter). Furthermore, the charging device 1 has a second power supply side converter 9, a third power supply side converter 11, a fourth netzungsanschlussussi inverter 13, a fifth netzanschlusssei ^¬ term inverter 15, a sixth power supply side inverter 17, a seventh power supply side converter 19 and an eighth power supply side converter 21st on.

An input 23 of the first network-connection-side converter 7 is electrically connected by means of a power-transmitting electrical connec ^¬ tion 25 with a network connection 27 of the charging device 1. The power connector 27 is used for switching circuit of the charging device 1 29 to a power supply network The power supply network 29 may be as example ^¬ be a low-voltage grid (eg with 400V three-phase alternating current).

An output 31 of the first network-connection-side converter 7 is electrically connected via a power-transmitting connection 32 to a DC link 33, which is designed as a DC intermediate link (DC power link 33).

The inputs of the network connection side converter 7, 9, 11, 13, 15, 17, 19 and 21 are also electrically connected via Leistungsübertra ^¬ ing electrical connections to the power connector 27; the outputs of these network connection side inverters are electrically connected to the DC intermediate circuit ^¬ 33. The mains side converter 7, 9, 11, 13, 15, 17, 19 and 21 are electrically parallel switched ^¬ ge. The DC intermediate circuit 33 is electrically connected to a

Input 35 of a first charging terminal-side converter 37 is connected. An output 39 of the first charging terminal-side converter 37 is electrically connected via a power-transmitting connection 41 to a first charging terminal 43 of the charging unit. direction 1 connected. The power-transferring compounds are being ^¬ staltet as lines with high current carrying capacity, and is provided in the figure with lines thicker line thickness ^¬.

The first charging port 43 is formed in the embodiment as an electrical cable, which is provided with an electrical ^¬ charging plug or an electrical charging socket (the charging plug or the charging socket are not shown in the figure). At the first charging port 43, a direct electrical current for charging the driving battery 3 of the electrically driven vehicle 5 can be provided.

Furthermore, in the same way to the DC link 33, a second load terminal-side inverter 45 is connected whose output is electrically connected to a second charging area ^¬ circuit 47th Likewise, the charging device 1 ^¬ a third charging port side converter 49, whose output is connected to a third charging terminal 51

is electrically connected, and a fourth charging ^¬ side inverter 53, whose output is electrically connected to a fourth charging ^¬ connection 55, on. At the second charging port 47, the third charging port 51 and the four ^¬ th charging port 55 each another electrically powered vehicle can be electrically connected.

The DC charging device 1 may for example also be part of a so-called DC satellite charging system, in which the charging ports 43, 47, 51 and 55 are each led to fixed charging stations (the so-called satellite), where then the respective electrically driven Vehicle is connectable.

Via data links 60, a controller 62 of the charging device 1 is connected to the line-side converters and to the load-port-side converters. Via these data connections, the controller 62 (controller 62) can receive messages or signals from the individual converters and transmit messages or signals to the individual inverters. send. The controller 62 represents an in-charger controller 62. The controller 62 may be configured, for example, as a microprocessor. The data connections 60 are, for example, as data lines or a bus system (such as a CAN bus) ausgestal ^¬ tet and thinner in the figure by lines line thickness Darge ^¬ represents. By means of messages or signals, the controller 62 can connect or disconnect each of the power supply-side converters and / or each of the charge-side converters (eg, switch on or off) or send information to these inverters. In other words, the controller can address by means of these messages or signals the netzanschlusssei ^¬ term inverter and the charging terminal side inverter.

The first power supply side converter 7 has a voltage setting unit 70 operating as a master. This voltage setting unit may set to be output at the output 31 of the f ^¬ th grid connection side converter 7 ^¬ output voltage to selectable within wide limits voltage values. The possibilities of output voltage adjustment in a converter (eg by means of pulse width modulation) are known in the art and need not be explained in detail here. The other mains-side converter 9, 11, 13, 15, 17, 19 and 21 each have a slave processing ^¬ tend voltage setting unit includes: a second voltage setting unit 72, a third Spannungseinstel ^¬ averaging unit 74, a fourth voltage setting unit 76, a fifth voltage setting unit 78, a sixth voltage setting unit 80, a seventh voltage ^{setting unit} 82 and an eighth voltage setting unit 84. The voltage setting units are connected to each other via an additional fast data connection 85

connected, for example via a so-called. Hard wiring (point-to-point wiring). The configured as a master voltage setting unit 70 sets the output voltage of the inverter 7 to a Span ^¬ tion value and sends this voltage value as a setpoint (common setpoint) to the working as a slave voltage setting units. These configured as a slave voltage setting units receive the common setpoint value from the designed as a master Spannungseinstel ^¬ averaging unit 7, and provide the output voltages of their order ^¬ judge this target value.

In the embodiment the network terminal is formed as a roller ^¬ selstrom power connector 27 27; the term netzanschlusssei- inverter 7, 9, 11, 13, 15, 17, 19 and 21 are AC ^¬ DC-DC converter and the intermediate circuit 33 is a DC intermediate circuit. The charge-side Umrich ^¬ ter 37, 45, 49 and 53 are DC-DC converters.

The charging device 1 works in principle as shown in the following ^¬ . The electrical energy supply network 29 supplies the charging device 1 via the power connector 27 with electrical energy. This electrical energy is supplied in the form of alternating current to the inputs of the line-side inverters. In the initial state of the charging device be ^¬ all inverters are in the idle state (standby), ie there is no electrical energy flowing through the inverter. If, for example, the first mains-side converter 7 is switched on, then the alternating current is converted by the converter 7 into direct current and this direct current is forwarded via the output 31 to the DC intermediate circuit 33. If one of the network connection side inverters is switched off, this switched off inverter acts like an opened switch; This switched off inverter is not responsible for the supply of the

DC link with electrical energy or electrical power at.

The provided at the direct current intermediate circuit 33 electrical ^¬ specific energy is converted by means of the charging port side converter in a DC voltage on the other and / or other current; this DC current is at the charging terminals Provided 9 and transmitted to the attached Schlos ^¬ Senen to the charging terminals vehicles. By way of example, the first charging connection-side converter 37 transmits electrical energy in the form of direct current via the first charging connection 43 to the vehicle 5 connected to this charging connection.

Of the first charging terminal 43 associated ladeanschlusssei ^¬ term inverter 37 transmits information on the over the charging port 43 to be transmitted electrical power over the data link 60 to the controller 62. In response to this information, the control switches 62 (transmitted by via the data link 60 messages or Signals) the power supply side converters either to (or leave them in their present state). The controller 62 monitors means of the charging terminal side Um ^¬ judge so the on the charging ports 43, 47, 51 and 55 to be transmitted electrical power continuously and switches if necessary continuously the network connection side inverter or off.

The following is an exemplary process sequence is angege ^¬ ben. At the first charging port 43, the first electrically driven vehicle 5 is connected and is charged by the charging ^¬ device 1. For this purpose, only a small electrical charging power is necessary, therefore, only the first power supply side inverter 7 is switched on. A short time later, a second electrically driven vehicle is additionally connected to the second charging port 47 and is to be charged via this second charging port 47. This second vehicle transmits information concerning the Benö ^¬ preferential charging power, via the second charging terminal 47 to the second charging terminal side converter 45, which then sends this information via a message 88 via the data link 60 to the controller 62nd The Steue- tion recognizes that the information provided by the first netzanschlussseiti ^¬ gen inverter 7 electrical power is insufficient to charge the two vehicles and that therefore the second network connection-side inverter must be switched on 9 62nd Then, the controller 62 sends a message / signal 90 via the data connection 60 to the first netzanschlussseiti ^¬ gen inverter 7. With this message, it tells the first network connection side inverter 7 (which works as a master) that now additionally the second network connection side inverter 9 is switched on is to be sent and that the setpoint to the second power supply side inverter 9 should be sent. Then, the first mains side converter 7 sends the value of the output voltage as a desired value by means of a message 92 used by him via the additional fast data connection 85 to the second netzanschlusssei ^¬ term inverter 9. (Alternatively, however, could this message 92 transmitted over data link 60 be.) the message 92 passes through the additional rapid movement of such data ^¬ connection 85 to the second voltage setting unit 72 of the second grid connection side converter 9. Thereafter, the voltage setting unit 72 is known to be output at an output 94 of the second grid connection side converter 9 output voltage (on the received common) set value to be set, that is, the output voltage from ^¬ this desired value is to assume.

Thereafter, the controller 62 sends another message 96 to the second network connection side inverter 9. This message 96 contains the information that the second network connection side inverter 9 is now to be turned on. In response, the voltage setting unit 72, the output voltage of the second power connector side converter 9 to the desired value, and turns off the second power connector ^¬ side converter to 9. The output voltage output at the output 94 of the second network-connection-side converter 9 now has the same voltage level as the output voltage output at the output 31 of the first network-connection-side converter 7. Therefore, via the DC intermediate circuit 33, no compensation currents flow between the first network connection side converter 7 and the second network connection side converter 9. If required, the output voltage of the switched-on mains-side converter 9 is continuously set to the setpoint value, ie adjusted to the setpoint value. As a result, power losses are avoided within the charging device 1 and it is a very energy-efficient operation of Ladeein ^¬ direction allows.

If (eg, by connecting another vehicle to the charging device), the demand for electrical charging power increases, then, for example, the third mains-side converter 11 is switched on. The described process steps are repeated accordingly.

If the first mains side converter 7 or the first voltage setting unit 70 should be covered by this inverter from ^¬, the controller 62 is informed by means of an error ^¬ object and a voltage setting unit of another network-terminal-side inverter takes over the function of the master.

Preferably, power factor correction units which are input side ^¬ belongs to the network-connection-side inverters configured as a master or as a slave and ^¬ take the voltage setting of the output voltage. These reactive current compensation units thus serve as voltage adjustment units. Such reactive current ^compensation units (so-called APFCS = Active Power Factor Correction Stages) can preferably ensure a high network quality. In addition, the charging devices become more efficient because no unnecessary reactive power is generated.

In the method described and the charging device described advantageously buck converters (Buck Converter) between the outputs of the mains terminal inverters and the DC link are required. With such, the network-connection-side converters nachge ^¬ off down converters could be the output voltage of each inverter to each other even adjust, but would occur in these buck converters additional power losses.

A charging device and a method for operating this charging device has been described in which a voltage adjustment unit operating as a master is arranged in one of the network connection side converters and a voltage adjustment unit operating as a slave is arranged in each of the remaining network connection side converters. These voltage setting units are used to set the output voltage of the inverters to a common setpoint. This ensures that no equalizing current flows between the outputs of the individual converters. This reduces the power loss and thus increases the efficiency of the charging ^{¬ device} .

Claims

claims

A method for operating a charging device (1) for electrically charging a traction battery (3) of an electrically driven vehicle (5), wherein the charging device (1) has a mains connection (27) for connecting the charging device to a power supply network (29), at least one Charging terminal (43) for connecting an electrically driven vehicle (5), and a plurality of electrical converters (7, 9, 11, 13, 15, 17, 19, 21) whose inputs (23)

are electrically connected to the mains connection (27) and whose outputs (31) are electrically connected to an intermediate circuit (33) of the charging device comprises,

wherein in the method

- The output voltages of at least two of the inverter (7, 9) are set to a common setpoint.

2. The method according to claim 1,

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

- the setpoint of one of the inverters (7) operating as a master is sent (92) to at least one of the other inverters (9) of the plurality operating as a slave.

3. The method according to claim 1 or 2,

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

- After receiving the desired value of the at least one operating as a slave inverter (9) whose output voltage is set to the desired value.

4. Method according to one of the preceding claims, characterized in that

- The inverter (7, 9, 11, 13, 15, 17, 19, 21) of the plurality during operation of the charging device (1) depending on the need for electrical charging power individually switched on or off, wherein before or at the connection one of the inverters (9) whose output voltage is set to the desired value.

5. The method according to any one of the preceding claims,

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

- Is communicated by a controller (62) of the charging device (1) working as a master inverter (7) (90) to which operating as a slave inverter (9) to send the setpoint.

6. The method according to any one of the preceding claims,

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

- The Umricher (7, 9, 11, 13, 15, 17, 19, 21) AC-DC converter and the intermediate circuit (33) is a DC link.

7. charging device (1) for electrically charging a Fahrbat- terie (3) of an electrically driven vehicle (5)

a mains connection (27) for connecting the charging device (1) to a power supply network (29),

at least one charging connection (43) for connecting an electrically driven vehicle (5),

a plurality of electrical converters (7, 9, 11, 13,

15, 17, 19, 21) whose inputs (23) are electrically connected to the mains connection (27) and whose outputs (31)

electrically connected to a DC link (33) of the charging device (1), wherein

- At least two of the inverter (7, 9) are arranged to set their output voltages to a common setpoint ^¬ .

8. Loading device according to claim 7,

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

- One of the inverters (7) is set up as a master, which sends the set value to the other inverters (9, 11, 13, 15, 17, 19, 21), and

- the other inverters (9, 11, 13, 15, 17, 19, 21) as

Slaves are set up.

9. Loading device according to claim 7 or 8,

characterized in that - The converters (7, 9, 11, 13, 15, 17, 19, 21) of the plurality each individually switched on or off, and that the inverter (7, 9, 11, 13, 15, 17, 19, 21) are set to adjust their output voltage to the setpoint before or during connection.

10. Loading device according to one of claims 7 to 9,

marked by

- A controller (62) which is arranged to communicate to the working as a master inverter (7), to which as

Slave operating inverter (9) to send the setpoint.

11. The charging device according to claim 7, wherein:

12. Charging device according to one of claims 7 to 11, e e c e e n e c e s e d e r c h

- At least one charging terminal side inverter (37, 45, 49, 53), the input (35) to the intermediate circuit (33) and the output (39) to the charging port (43) is connected.