DE102019207449A1 - Method for charging a battery of an electrically powered vehicle and electrically powered vehicle - Google Patents

Abstract

The invention relates to a method for charging a battery of an electrically powered vehicle (50), a current collector (1) being arranged on the vehicle (50) and being connected to an external power supply (10) while driving on a charging path (11) , wherein for charging the battery (2) of the vehicle (50) via the pantograph (1) and the external energy supply (10) on the charging path 811) a target speed (20) of the vehicle (50) depending on a target state of charge (21) of the battery (2) is determined by means of a control device (3) and an actual speed of the vehicle (50) is adapted to the determined target speed (20) and / or the determined target speed (20) is output . The invention also relates to an electrically powered vehicle (50).

Description

The invention relates to a method for charging a battery of an electrically powered vehicle and to an electrically powered vehicle.

Electrically powered vehicles usually have an energy store in the form of a battery. In most cases, this battery is charged using an external energy source when the vehicle is stationary. However, there are also systems in which the vehicle's battery can be charged while driving via an external energy source, for example an overhead line or an induction system.

From the EP 1 997 668 A1 a public transport system, an electrically powered vehicle and a charging station for such a system are known. To charge the vehicle, the vehicle can be connected to an overhead line by means of a pantograph.

The invention is based on the object of creating a method for charging a battery of an electrically driven vehicle and an electrically driven vehicle in which the charging of the battery is improved.

According to the invention, the object is achieved by a method having the features of claim 1 and a vehicle having the features of claim 6. Advantageous embodiments of the invention emerge from the subclaims.

In particular, a method for charging a battery of an electrically powered vehicle is provided, wherein a current collector is arranged on the vehicle and is connected to an external power supply while driving on a charging path, wherein for charging the battery of the vehicle via the current collector and the external energy supply on the charging path, a target speed of the vehicle is determined as a function of a target state of charge of the battery by means of a control device and an actual speed of the vehicle is adapted to the specific target speed and / or the specific target speed is output.

Furthermore, an electrically powered vehicle is provided, comprising a current collector for establishing an electrical connection with an external energy supply while driving on a charging path, a battery, and a control device, the control device being designed to charge the battery of the vehicle via the current collector and the external energy supply on the charging path to determine a target speed of the vehicle as a function of a target state of charge of the battery and to adapt an actual speed of the vehicle to the determined target speed and / or to output the determined target speed.

The method and the vehicle make it possible to bring a battery of the vehicle to a target state of charge (also referred to as state of charge, SOC) in a targeted manner. Since an available charging path is usually of finite length, the vehicle's battery cannot be charged for any length of time, because a charging time is limited by the time that the vehicle drives along the charging path. The charging time must therefore be adjusted in order to achieve the target state of charge. For this purpose, a target speed is calculated, which means that the battery of the vehicle reaches the target state of charge at the latest after the charging path has been completely covered. The target speed is in particular an upper limit or a maximum speed that must not be exceeded in order to achieve the target state of charge in any case by the end of the charging path.

The advantage of the invention is that a charging strategy can be provided in which a target charge state is achieved in a targeted manner. In this way, for example, it can be prevented that bottlenecks occur in an energy supply on routes outside the charging routes, that is to say on routes where charging is not possible. The charging strategy can be determined and established, for example, taking into account a current travel route and / or alternative travel routes. In this case, road maps in particular can be taken into account on which charging routes with an associated length are stored. The road maps can be called up, for example, by means of the control device from a navigation device of the vehicle.

The control device can be designed as a combination of hardware and software, for example as program code that is executed on a microcontroller or microprocessor.

The electrically powered vehicle can be a purely electrically powered vehicle or a hybrid vehicle. The vehicle can be a passenger car or a utility vehicle. In addition to the pantograph, the battery and the control device, the vehicle includes other devices, such as a battery control, etc.

In one embodiment it is provided that the target speed is determined on the basis of an actual state of charge, the target state of charge, a length of the charging path of the external energy supply and a charging power of the battery. The actual state of charge refers to the state of charge of the battery at the beginning of the charging path. It can be provided that the actual state of charge is measured and / or estimated by means of the control device on the basis of a current state of charge of the battery, a current power consumption and a time until the start of the charging path. The charging power of the battery is determined in particular on the basis of a power supplied by the external energy supply. An electrical drive power of the vehicle and possibly a power of consumers in a low-voltage network of the vehicle are subtracted from this delivered power. It can be provided that a power delivered by the external energy supply, the drive power and / or a power of further loads are estimated by means of the control device in order to determine the charging power.

In a simple case, the target speed is calculated using the following equation, for example: $$\begin{array}{c}\text{Target speed}=\left(\text{Distance * charging power}\right)/\\ \text{Energy difference between the target and actual state of charge}\end{array}$$

The target speed is specified in km / h, the distance in km, the charging power in W and the energy difference in Wh.

To determine the target speed, it was assumed in this simple example that this is constant over the entire charging distance. However, this does not have to be the case. It can also be provided that the target speed changes over the loading distance. For this purpose, for example, a setpoint speed function is then determined as a function of the distance or time. In this way, for example, different speed specifications and / or gradients on the loading route can be taken into account.

If a charging power changes over the charging section, for example because a larger or smaller number of vehicles are simultaneously tapping power on the charging section, this can also lead to a change in the setpoint speed. It can then be provided that the target speed is determined continuously on the basis of current values for a remaining charging distance, a current or future charging power and a current energy difference between the target and the actual state of charge of the battery.

Properties of the route can be queried for example by means of the control device from a navigation device of the vehicle or can be provided by another service provider, for example online via the Internet.

In one embodiment it is provided that the determination and adaptation or suggestion takes place only in a charging mode of the vehicle. In this case, a distinction is made between a normal mode and a charging mode. In normal mode, no target speed is calculated and the actual speed is not adapted to the specific target speed. Likewise, there is no output of the specified setpoint speed in normal mode. This only takes place if the charging mode is activated. The normal mode and the charging mode can be optionally activated and deactivated, for example, by a driver of the vehicle.

In a further embodiment it is provided that a setpoint drive state is additionally determined in front of and / or on the charging section and a drive of the vehicle is activated accordingly or a drive recommendation is output. This makes it possible to deactivate a drive of the vehicle in advance even before reaching a charging section, so that the vehicle only reaches the beginning of the charging section with the kinetic energy still available. This allows energy stored in the battery to be saved. In particular, this enables the actual speed of the vehicle to be planned in advance. If the target speed determined for loading is lower than an actual If the speed of the vehicle is reached before the charging section is reached, the vehicle can switch off or reduce a drive in advance before the start of the charging section in order to reach the specified target speed at the beginning of the charging section. At the same time, this can save energy.

In a further embodiment it is provided that the external energy supply is designed as an overhead line system or as an induction system. In principle, however, the external power supply can also be designed differently, for example as a busbar system running laterally.

Features for designing the vehicle emerge from the description of the design of the method. The advantages of the vehicle are in each case the same as in the embodiments of the method.

• 1 eine schematische Darstellung einer Ausführungsform des Fahrzeugs;
• 2 ein schematisches Ablaufdiagramm einer Ausführungsform des Verfahrens mit einem Lademodus;
• 3 eine schematische Darstellung einer Funktion zum Bestimmen einer Soll-Geschwindigkeit;
• 4 eine schematische Darstellung zum Bestimmen eines Ladezustands einer Batterie am Ende der Ladestrecke.

The invention is explained in more detail below on the basis of preferred exemplary embodiments with reference to the figures. Here show:

• 1 a schematic representation of an embodiment of the vehicle;
• 2 a schematic flow diagram of an embodiment of the method with a charging mode;
• 3 a schematic representation of a function for determining a target speed;
• 4th a schematic representation for determining a state of charge of a battery at the end of the charging path.

In 1 Figure 3 is a schematic representation of an embodiment of the vehicle 50 shown. The vehicle 50 includes a pantograph 1 for establishing an electrical connection with an external power supply 10 while driving on a charging line 11 , a battery 2 and a control device 3 .

The vehicle 50 is in the example shown is as a commercial vehicle 60 formed, but can in principle also be formed differently, for example as a passenger car. The external energy supply 10 is exemplary as an overhead contact line system 13 formed, but can in principle also be formed differently, for example as an induction system.

The control device 3 is designed to charge the battery 2 of the vehicle 50 via the pantograph 1 and the external energy supply 10 on the charging line 11 a target speed 20th of the vehicle 50 depending on a target charge level 21st the battery 2 to determine.

The target state of charge 21st can be specified manually, for example. Alternatively, the target state of charge 21st depending on a route planning, for example a navigation device (not shown) of the vehicle, which, in addition to navigation, also a charging strategy for the battery 2 of the vehicle 50 coordinated.

The control device 3 determines the target speed 20th based on an actual state of charge 22nd , the target state of charge 21st , one length 12 the charging route 11 the external energy supply 10 and a charging power 23 the battery 2 . The actual state of charge 22nd the battery 2 becomes the control device 3 for example provided by a battery control (not shown) and / or provided by this by means of the control device 3 queried. The length 12 the charging route 11 can the control device 3 for example from a navigation device (not shown) of the vehicle 50 provided and / or queried by this. The navigation device can, for example, the length 12 determine based on a road map. The charging power 23 is for example by means of the control device 3 based on information about the charging route 11 and an estimated power consumption of an electric drive and low-voltage consumers of the vehicle 50 estimated.

It can be provided that the actual speed of the vehicle 50 by means of the control device 3 to the specified target speed 20th is adjusted. To this end, the control device transfers 3 the determined target speed 20th for example a longitudinal control 51 of the vehicle 50 which then sets the actual speed to the specific target speed 20th regulates.

Alternatively or additionally it can also be provided that the control device 3 the determined target speed 20th , for example as a target speed signal 24 , outputs, where the target speed 20th or the target speed signal 24 then on a display device 52 of the vehicle 50 is displayed to a driver of the vehicle 50 thereby a speed recommendation for the charging distance 11 can be given.

It can be provided that the control device 3 additionally a target drive state 25th in front of and / or on the charging line 11 determined and a drive of the vehicle 50 is controlled accordingly or a drive recommendation 26th is issued.

It can be provided that the determination and adaptation or suggestion is only carried out in a charging mode of the vehicle 50 he follows. This is illustrated in a schematic flow chart that is shown in FIG 2 is shown.

Is done in one process step 100 found that an electrical connection with an external power supply has been established, then in a method step 101 checks whether the vehicle is in a normal mode 14th or a charging mode 15th is located.

The vehicle is not in a charging mode 15th , the described method is not carried out, nor is a setpoint speed determined, adjusted or output.

On the other hand, if the vehicle is in the charging mode 15th , so the procedure is in process step 102 executed and a target speed is determined, adjusted and / or output.

In 3 a schematic representation of an exemplary function for determining a setpoint speed of the vehicle in the area of the charging path is shown. The case here is shown that the battery reaches a specified target state of charge of 100% at the end of the charging path.

A charging route with a length of 5 km was assumed here as an example. A charging power of the battery is 24000 W and an energy difference in the example 3000 Wh between 70% state of charge and 100% state of charge of the battery. The target speed (in the example 40 km / h) can then be calculated in the simplest case using the following equation: $$\begin{array}{c}\text{Target speed}\left[\text{km}/\text{H}\right]=\left(\text{Distance}\left[\text{km}\right]\text{* Charging power}\left[\text{W.}\right]\right)/\\ \text{Energy difference between the target and actual state of charge}\left[\text{Wh}\right]\end{array}$$

On the x-axis 30th the 3 is the actual state of charge of the battery at the beginning of the charging path. On the y-axis 31 the target speed is plotted. The representation is read as follows: If a vehicle with an actual state of charge of 70% drives into the charging section, you must drive at a target speed of 40 km / h so that the battery is fully charged at the end of the charging section.

In 4th a schematic representation for determining a state of charge of a battery is shown. On the x-axis 30th the speed at which the vehicle enters the charging section is plotted. On the y-axis 31 the resulting state of charge (SOC) of the battery at the end of the charging path is plotted. There are four turns 32 , 33 , 34 , 35 shown which each belong to a different actual state of charge of the battery at the beginning of the charging route. The actual state of charge shown is 25% (curve 32 ), 50% (curve 33 ), 75% (curve 34 ) and 100% (curve 35 ).

The parameters used in this example are the same as in the example presented in the 3 is shown. The representation is read as follows: If a vehicle with an actual state of charge of 50% drives into the charging path (curve 33 ) and drives through the charging section at a speed of 60 km / h, the state of charge of the battery at the end of the charging section is 70%. At a speed of 40 km / h, however, the state of charge of the battery at the end of the charging route is 80%. In order to fully charge the battery until the end of the charging path, the speed of the vehicle must not exceed 24 km / h.

Based on the 3 and 4th The control device can determine corresponding setpoint speeds.

List of reference symbols

1

Pantograph

2

battery

3

Control device

10

external energy supply

11

Charging line

12

length

13

Catenary system

14th

Normal mode

15th

Charging mode

20th

Target speed

21st

Target state of charge

22nd

Actual state of charge

23

Charging power

24

Target speed signal

25th

Target drive state

26th

Drive recommendation

30th

X axis

31

y-axis

32

Curve (25% SOC)

33

Curve (50% SOC)

34

Curve (75% SOC)

35

Curve (100% SOC)

50

vehicle

51

Longitudinal regulation

52

Display device

60

Commercial vehicle

100-102

Procedural steps

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• EP 1997668 A1 [0003]

Claims (10)

A method for charging a battery of an electrically powered vehicle (50), wherein a current collector (1) is arranged on the vehicle (50) and is connected to an external power supply (10) while driving on a charging path (11), wherein for charging the battery (2) of the vehicle (50) via the pantograph (1) and the external energy supply (10) on the charging path 811) a target speed (20) of the vehicle (50) depending on a target state of charge (21) of the Battery (2) is determined by means of a control device (3) and an actual speed of the vehicle (50) is adapted to the determined target speed (20) and / or the determined target speed (20) is output. Procedure according to Claim 1 , characterized in that the target speed (20) is based on an actual state of charge (22), the target state of charge (21), a length (12) of the charging path (11) of the external energy supply (10) and a charging power ( 23) of the battery (2) is determined. Procedure according to Claim 1 or 2 , characterized in that the determination and adaptation or suggestion takes place only in a charging mode of the vehicle (50). Method according to one of the preceding claims, characterized in that a target drive state (25) is additionally determined in front of and / or on the loading path (11) and a drive of the vehicle (50) is controlled accordingly or a drive recommendation (26) is output . Method according to one of the preceding claims, characterized in that the external energy supply (10) is designed as an overhead line system (13) or as an induction system. An electrically powered vehicle (50) comprising: a current collector (1) for establishing an electrical connection with an external energy supply (10) while driving on a charging path (11), a battery (2), and a control device (3), wherein the control device (3) is designed to charge the battery (2) of the vehicle (50) via the current collector (1) and the external energy supply (10) on the charging path (11) at a target speed (20) of the vehicle (50) as a function of a target state of charge (21) of the battery (2) to be determined and an actual speed of the vehicle (50) to be adapted to the specific target speed (20) and / or the specific target speed (20) to spend. Vehicle (50) after Claim 6 , characterized in that the control device (3) is also designed in such a way that the target speed (20) on the basis of an actual state of charge (22), the desired state of charge (21), a length (12) of the charging path (11) the external energy supply (10) and a charging power (23) of the battery (2). Vehicle (50) after Claim 6 or 7th , characterized in that the control device (3) is further designed to determine the target speed (20) only in a charging mode of the vehicle (50) and to adapt the actual speed or to suggest it. Vehicle (50) according to one of the Claims 6 to 8th , characterized in that the control device (3) is designed to additionally determine a target drive state (25) in front of and / or on the loading path (11) and to control a drive of the vehicle (50) accordingly or a drive recommendation (26) to spend. Vehicle (50) according to one of the Claims 6 to 9 , characterized in that the vehicle (50) is a utility vehicle (60).

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