Abstract:
A method is provided for setting up an on-board charger in an electrically driven vehicle with the following features: a proxy resistor of a charging socket of the vehicle is queried ( 44, 68 ); if the proxy resistor is present ( 46 ), a master configuration ( 48, 50, 52 ) of the on-board charger is carried out; and if the proxy resistor is not present ( 70 ), a slave configuration ( 72, 74, 76 ) of the on-board charger is carried out.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority under 35 USC 119 to German Patent Appl. No. 10 2015 103 193.0 filed on Mar. 5, 2015, the entire disclosure of which is incorporated herein by reference. 
       BACKGROUND 
       [0002]    1. Field of the Invention. The invention relates to a method for setting up an on-board charger in an electrically driven vehicle. The invention also relates to a corresponding apparatus, a computer program and a storage medium. 
         [0003]    2. Description of the Related Art. A plug-in vehicle is known in automotive technology as an electrically driven hybrid or electric vehicle with a traction battery that can be charged by an electrical connection to a stationary power supply system. A plurality of on-board chargers (OBC) may be arranged in such a vehicle for particularly rapid charging. In such a case, only one on-board charger is connected electrically to the charging socket of the vehicle and is connected logically as the “master,” while the other (optional) on-board chargers are connected logically as “slaves” and are connected to the “master” only via a communication line. 
         [0004]    EP 2 618 451 A2 discloses a charger network set up by a method that includes switching-on a charger that carries out a self-test. The charger communicates with the network via a communication means, sets itself as master and delivers energy to a battery pack. 
         [0005]    DE 10 2012 200 489 A1 discloses a charging system for use in a vehicle for charging a vehicle battery with a first charging apparatus and a second charging apparatus. The charging apparatuses are connected to a vehicle bus. Each charging apparatus has a master display digital input and decodes the input to determine its role as the master charging apparatus or the slave charging apparatus. The master charging apparatus configures its connection to the vehicle bus so that a master node message record is used. The slave charging apparatus configures its connection to the vehicle bus so that a slave node message record is used. 
         [0006]    DE 10 2011 017 567 A1 describes a twin charger system for charging a battery with current that is controlled by two chargers connected to the battery in a parallel. One of the chargers is operated in accordance with a voltage control mode and the other charger is operated in accordance with a current control mode. 
       SUMMARY 
       [0007]    The invention provides a method for setting up an on-board charger in an electrically driven vehicle, a corresponding apparatus, a corresponding computer program and a corresponding storage medium. 
         [0008]    This approach is based on the fundamental idea of providing standard software for each on-board charger (that is to say for both the “master” and the “slave” at the same time). The software is adapted automatically the first time the vehicle is connected to the stationary power supply system. In this case, the on-board charger electrically connected to the charging socket of the vehicle is configured as the “master.” Possibly additional on-board chargers that are not connected electrically to the charging socket are configured as “slaves” for communication with the “master”, whereby the system is configured automatically for the corresponding charging power (for example 11 kW or 22 kW) depending on the number of on-board chargers in the vehicle. 
         [0009]    This has the advantage that the software for the “master” and for the “slave” can be maintained uniformly, serviced and tested. Additionally, software must be installed only once during production of the vehicle. 
         [0010]    Automatic configuration of the master or slave is provided by querying the proxy resistor of the charging socket. This proxy resistor usually is used to detect when a charging plug is plugged into the charging socket. The charging plug has a temporary resistor that is connected electrically in parallel with the proxy resistor and is evaluated using a logic unit in the on-board charger. A voltage can be detected using the logic unit in the on-board charger even if the charging plug has not been inserted, and that voltage can be used to detect the charging socket. 
         [0011]    Provision also is made for the range of functions of the programmable logic controller (PLC) present as standard in an on-board charger to be activated only when the on-board charger is connected as the master. There is a saving in the quiescent current by deactivating the PLC functionality in on-board chargers connected as the slave. 
         [0012]    One exemplary embodiment of the invention is illustrated in the drawings and is described in more detail below. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  shows the situation on which a method according to the invention is based. 
           [0014]      FIG. 2  is a simplified program flowchart of the method. 
       
    
    
     DETAILED DESCRIPTION 
       [0015]      FIG. 1  illustrates a vehicle with a master on-board charger  10  that connects to the entire charging socket peripherals  18  via a charging socket connection  16  and detects and deals with the entire insertion procedure. In contrast, a slave on-board charger  12  is only responsible for providing the additional power. The concept is offered to charge the traction battery  14  more quickly on public infrastructure. All relevant data for controlling the charging process are interchanged between the master  10  and the slave  12  via a communication path (controller area network, CAN). The master on-board charger  10  is always connected to the charging socket  18 , whereas the slave  12  is connected only to the alternating current distribution  20 , direct current distribution  22  and communication line between the master  10 . 
         [0016]      FIG. 2  illustrates, by way of example, the sequence of a method  30  according to the invention in the situation according to  FIG. 1 . 
         [0017]    The starting point of the method  30  is formed by the installation (step  32 ) of the on-board chargers  10 ,  12  in the vehicle. The first on-board charger  10  is connected (step  34 ) to the charging socket  18 , alternating current distribution  20 , direct current distribution  22  and communication. The second on-board charger  12  is installed (step  36  only at the alternating current distribution  20 , direct current distribution  22  and communication. The on-board charger  10  is connected (step  38 ) to the charging socket  18 , whereas the on-board charger  12  is not connected (step  40  to the charging socket  18 . 
         [0018]    The steps illustrated in hatched form in  FIG. 2  can be assigned to the learning phase of the underlying algorithm. 
         [0019]    In the case of the on-board charger  10 , a proxy resistor of the charging socket  18  initially is queried (step  44 ). Since the proxy resistor is present (step  46 ), the on-board charger  10  is coded (step  48 ) as the master by virtue of its relevant programmable logic controller being activated. During this master configuration (steps  48 ,  50 ,  52 ), the on-board charger  10 , on the one hand, configures (step  50 ) a CAN matrix stored in the on-board charger  10  as master and therefore activates the instruction set for controlling the charging of the subsequent slave on-board charger  12 . On the other hand, the on-board charger  10  configures (step  52 ) its history memory as master, thus defining, inter alia, the conditions for a charging request of 22 kW by the on-board charger  10 . 
         [0020]    After the described master configuration  48 ,  50 ,  52 , the on-board charger  10  transmits (step  54 ) a signal (flag) on the CAN and waits for the relevant confirmation by the further on-board charger  12  provided as the slave for a predefined period (timeout  58 ), preferably in seconds. If the acknowledgement by the on-board charger  12  were absent (step  60 ) over this period, the on-board charger  10  would configure itself (step  62 ) for individual operation (standalone) with a total charging power of 11 kW and would make a corresponding diagnosis (step  64 ). 
         [0021]    However, even the on-board charger  12  which is not connected ( 66 ) to the charging socket  18  queries its proxy resistor (step  68 ). Since the proxy resistor is not present here (step  70 ), the on-board charger  12  is configured as a slave (step  72 ) by virtue of the programmable logic controller reserved only for the master  10  being deactivated. 
         [0022]    During the slave configuration (steps  72 ,  74 ,  76 ), the on-board charger  12  also configures the CAN matrix (step  74 ) stored therein as slave and therefore activates the instruction set for controlling the charging by the master  10 ; it also configures ( 76 ) its history memory as slave, thus defining the conditions for a charging request of 22 kW by the on-board charger  12 . 
         [0023]    After this slave configuration  72 ,  74 ,  76 , the on-board charger  12  gets ready to receive the signal on the CAN (step  78 ). During the period predefined for this purpose (step  80 ), the on-board charger  12  in the present scenario actually receives the signal (step  82 ), configures itself (step  84 ) for paired operation with a total charging power of 22 kW and transmits the relevant confirmation (step  84 ), via the CAN, to the master  10  which in turn receives the confirmation (step  86 ). 
         [0024]    In view of the acknowledgement given, the on-board charger  10  now configures the 22 kW charging system (step  88 ) in the vehicle, adjusts the charging power calculation to 22 kW (step  90 ), adaptively parameterizes the system automatically to 22 kW (step  92 ), starts communication in the vehicle (step  94 ) and stores all settings in the master  10  and in the slave on-board charger  12 .