Method for inductively charging a motor vehicle battery and motor vehicle

Abstract

A method for inductively charging a battery (5) of a motor vehicle (1), comprising a secondary-side energy transfer unit (4) arranged on the underbody, characterized in that a charging device (2) which is movable and / or slideable on a road surface (11) of the motor vehicle (1) and has a primary-side energy transfer unit (7) is guided under the underbody (3) of the motor vehicle (1) and electrical energy is transferred from the primary-side energy transfer unit (7) to the secondary-side energy transfer unit (4), wherein a request message requesting and / or planning the charging of the battery (5) by means of the charging device (2) is transmitted to a communication counterpart (16) by means of at least one communication device (15).wherein the request message includes planning information describing at least one predictive position and / or at least one predictive state of charge of the battery (5) of the motor vehicle (1), wherein the planning information is determined on the basis of a route determined by a navigation system (18) of the motor vehicle (1).

Description

[0001] The invention relates to a method for inductively charging a battery of a motor vehicle and motor vehicle, comprising a secondary-side energy transfer unit arranged on the underbody.

[0002] Inductive charging of the battery of a partially or fully electric vehicle is the subject of intensive development efforts by the automotive industry to avoid complex wired power transfer between a charging station and the vehicle. For this purpose, the vehicle has a secondary-side power transfer unit into which a voltage used for charging the battery can be induced from a primary-side power transfer unit. Since stationary primary-side power transfer units are typically integrated into the vehicle's underbody, the secondary-side power transfer unit is preferably located in the vehicle's underbody.

[0003] DE 10 2014 018 129 A1 discloses a method for charging an energy storage device in a motor vehicle by means of inductive energy transfer between a primary-side energy transfer unit, which is part of an inductive charging device, and a secondary-side energy transfer unit, which is part of the motor vehicle, wherein the primary-side energy transfer unit is moved linearly in a direction transverse to a direction of movement of the motor vehicle relative to a drivable surface.

[0004] DE 10 2013 106 436 A1 discloses a supply method for at least one electrically powered vehicle, in which at least one mobile generator is used to supply the at least one electrically powered vehicle with electrical energy at a location where the at least one electrically powered vehicle is located, and in which the supply of the at least one electrically powered vehicle is dependent on a state of the at least one electrically powered vehicle detected by means of a diagnostic interface.

[0005] DE 10 2011 112 610 A1 discloses a method for wirelessly inductively transmitting electrical energy to a motor vehicle, wherein a mobile station with devices for transmitting electrical energy to a vehicle has an automatically controlled robot arm which carries a primary part of a charging transmitter which is adapted to a corresponding secondary part on the vehicle and can transmit inductive electrical energy to it.

[0006] The invention is based on the objective of providing a more user-friendly method for inductively charging a motor vehicle.

[0007] To solve this problem, according to the invention, a method of the type mentioned at the outset provides that a charging device which can be driven and / or pushed on a road surface of the motor vehicle, with a primary-side energy transfer unit, is guided under the underbody of the motor vehicle and electrical energy is transferred from the primary-side energy transfer unit to the secondary-side energy transfer unit.

[0008] The invention is based on the idea of ​​enabling the charging of a motor vehicle's battery by means of a mobile charging device comprising a primary-side energy transfer unit, by designing this device to be movable and / or slideable so that it can be positioned under the motor vehicle, particularly when stationary. In other words, it is proposed to move the primary-side energy transfer unit into a space between the underbody of the motor vehicle and the road surface by moving and / or sliding the charging device, thereby charging the motor vehicle's battery. In this way, a motor vehicle designed for inductive charging by means of a stationary energy transfer unit integrated into the road surface can be charged particularly user-friendly by an operator of the charging device, especially when parked.This is particularly relevant in situations where no stationary energy transfer unit is available near the vehicle, thus enabling mobile battery charging.

[0009] A charging device can be used that includes a carrier to which the primary-side power transfer unit is attached. The carrier may also be equipped with several wheels and / or rollers for moving the charging device and / or means for reducing friction between the carrier and the vehicle surface to facilitate movement of the charging device. The carrier may also include a handle for the operator to move and / or control the charging device. The handle may, for example, comprise a grip, preferably positioned at a working height for the operator while standing or walking. The primary-side and secondary-side power transfer units typically each include a coil for generating a magnetic field. Additionally, the secondary-side power transfer unit may include a rectifier for rectifying an induced voltage.

[0010] Advantageously, the electrical energy is supplied by an electrical energy storage device of the charging unit. The charging unit can therefore be operated independently, allowing it to be moved to any location within the vehicle. Advantageously, the electrical energy storage device is also arranged on or attached to the aforementioned support. To generate an alternating voltage that supplies the coil of the primary energy transfer unit, the energy storage device can be connected to an oscillator. Alternatively or additionally, the electrical energy can be supplied via a connection on the charging unit from an external electrical power source. This connection can be made to the power source by means of a cable.The energy source could be, for example, another electrical energy storage device carried on the operator's service vehicle and connected to the charging device to provide electrical energy. An electromechanical generator or a public power grid are also conceivable energy sources. In this case, the primary-side energy transmission unit preferably includes a frequency converter.

[0011] According to a particularly preferred embodiment of the method according to the invention, a request message requesting and / or scheduling the charging of the battery by means of the charging device is transmitted to a communication counterpart by means of at least one communication device. This counterpart can then initiate the charging of the vehicle's battery by means of the charging device. The driver of the vehicle can initiate the transmission of the request message to request charging of the battery at the current location of the vehicle or at a predicted future location, for example, if the vehicle is parked for an extended period of time in a parking space without inductive charging capability.In a specific application of the method according to the invention, the communication counterpart can offer the provision of the charging device as a premium service to the driver of the motor vehicle, thus enabling the charging of the fully or partially depleted energy storage system of the motor vehicle even in remote locations without permanently installed primary energy transfer units. Typically, the communication line establishes an internet connection to the communication counterpart. Both a vehicle-integrated communication device and a portable communication device, for example, the driver's mobile phone with an application installed on it, can be used to transmit the request message.

[0012] Advantageously, the request message includes charge state information describing the current state of the battery and / or position information describing the current location of the vehicle. By evaluating the charge state information and / or the position information, the communication partner can then initiate the provision of a suitable charging device with sufficient energy to charge the battery.

[0013] In the case of a request message scheduling battery charging via the charging device, it is preferred that the request message includes planning information describing at least one predictive position and / or at least one predictive state of charge of the vehicle's battery, wherein the planning information is determined based on a route calculated by the vehicle's navigation system. Thus, from the route, optionally taking into account an energy consumption forecast for the vehicle, a need for charging via the charging device can be determined at the vehicle's predictive position or positions. Based on the predictive position and / or the predictive state of charge, the communication partner can then schedule the use of the charging device or devices, optionally from a spatially distributed network of available charging devices.

[0014] The underlying charging device is an inductive charging device for inductively charging a motor vehicle battery, comprising a secondary-side inductive energy transfer unit arranged on the underbody. The charging device is characterized by being drivable and / or slidable on the road surface of the motor vehicle and having a primary-side energy transfer unit for transferring electrical energy to the secondary-side energy transfer unit. The charging device can be configured to carry out the method according to the invention.

[0015] The charging device is preferably equipped with an electrical energy storage device and / or a connection to an external electrical energy source, whereby the electrical energy can be provided by the energy storage device and / or the energy source via the connection.

[0016] The problem underlying the invention is further solved by a motor vehicle comprising a battery and a secondary-side inductive energy transfer unit arranged on the underbody for charging the battery. The motor vehicle according to the invention is characterized in that a control unit, by means of which a request message requesting and / or planning charging of the battery by a charging device can be determined, and a communication device, by means of which the request message can be transmitted to a communication counterpart, are provided. The motor vehicle according to the invention can be configured to carry out the method according to the invention.

[0017] In the motor vehicle according to the invention, it is preferred if the request message includes charge state information describing the current state of charge of the battery and / or position information describing the current position of the motor vehicle.

[0018] Alternatively or additionally, a navigation system may be provided by means of which a route of the motor vehicle can be determined, wherein the request message includes planning information describing at least one predictive position and / or at least one predictive state of charge of the motor vehicle's battery, which can be determined by the control unit on the basis of the route.

[0019] All descriptions of the inventive method can be applied analogously to the charging device and the motor vehicle according to the invention, so that the aforementioned advantages can also be achieved with these.

[0020] Further advantages and details of the invention will become apparent from the exemplary embodiments described below and from the drawings. These are schematic representations and show: Fig. 1 a schematic diagram of an arrangement consisting of a motor vehicle according to the invention and an inductive charging device; and Fig. 2 a block diagram of the energy transmission units of the motor vehicle and the charging device.

[0021] Fig. Figure 1 shows a schematic diagram of an arrangement consisting of a motor vehicle 1 and an inductive charging device 2. The motor vehicle 1 has a secondary-side energy transfer unit 4 integrated into its underbody 3 for inductively charging a battery 5, by means of which a drive device 6 can be supplied for partial or complete electric propulsion of the motor vehicle 1.

[0022] The inductive charging device 2 comprises a primary-side energy transfer unit 7, which is mounted on a carrier 8 and can be supplied with energy by means of an electrical energy storage device 9, also mounted on the carrier 8. Several wheels 10 are also arranged on the carrier 8, by means of which the inductive charging device 2 can be moved along a common road surface 11 with the motor vehicle 1. Alternatively or additionally, the charging device 2 has means (not shown) for reducing friction between the carrier 8 and the road surface 11, so that the charging device 2 can be moved manually. To facilitate moving and / or shifting the charging device 2 by an operator, a handle 12 with a grip 13 is also arranged on the carrier 8.In order to inductively transfer electrical energy from the primary-side energy transfer unit 7 to the secondary-side energy transfer unit 4 for charging the battery 6, the charging device 2 is placed under the underbody 3 of the motor vehicle 1 and an energy flow from the electrical energy storage unit 9 to the primary-side energy transfer unit 7 is activated.

[0023] The motor vehicle 1 also has a communication device 15 for establishing a wireless internet connection with a communication counterpart 16. This is part of a distribution network for charging devices such as those in Fig. 1. Charging device shown. 2. Using the communication device 15, a driver of the motor vehicle 1 can transmit a request message to the communication counterpart 16, requesting that the battery 5 be charged using the charging device 2. A control unit 17 is provided on the vehicle side to determine the request message. The provision of such a service for charging the battery 5 at a location where, for example, no permanently installed primary-side energy transfer unit is available, can be booked by the driver as a special premium service.

[0024] According to one embodiment, the request message includes charge state information describing the current state of charge of battery 5 and position information describing the current position of the vehicle, which the control unit 17 retrieves from a navigation system 18 of the vehicle 1. Upon receiving the request message, the communication unit 16 can arrange for the charging device 2 to be moved to the position of the vehicle 1 and guided there by service personnel under the underbody 3 of the vehicle 1 to charge the battery 5. The communication unit 16 can then use the charge state information to check whether the energy stored in the electrical energy storage device 9 is sufficient to inductively charge the battery 5 of the vehicle 1.

[0025] In a further development of the previously described embodiment, the request message alternatively or additionally includes planning information describing several predictive positions and predictive charge states at these positions. This information is determined by the control unit 17 based on a route of the vehicle as determined by the navigation system 18 and describes at which predictive positions along the route recharging of the vehicle's battery 5 is expected to be necessary. The control unit 17 uses an energy consumption forecast to determine the predictive positions and predictive charge states. As a result of the transmission of this request message, the communication counterpart 16 can now plan several deployment locations for the respective charging unit 2 and initiate charging of the battery 5 at these deployment locations.

[0026] Alternatively or in addition to the vehicle-side communication device 15, the request message can be transmitted to the communication counterpart 16 by means of a portable communication device, for example an internet-enabled mobile phone with an installed application.

[0027] Fig.Figure 2 shows a block diagram of the energy transfer units 4 and 7. The primary-side energy transfer unit 7, connected to the energy storage device 9 of the charging device 2, has an oscillator 19 for converting the DC voltage provided by the energy storage device 9 into an AC voltage of a suitable frequency. This AC voltage is supplied to a primary-side coil 20, which generates the magnetic field for inductive energy transfer. An AC voltage is thus induced in a secondary-side coil 21 of the secondary-side energy transfer unit 4, which is rectified by means of a rectifier 22 and used to charge the energy storage device 5.

[0028] Alternatively or additionally to using the energy storage device 9, the charging device 2 has a connection for an external electrical energy source. This energy source can, for example, be a battery not carried on the mobile charging device, which is connected to the primary-side energy transfer unit 7 via a cable at this connection. It is also conceivable that the primary-side energy transfer unit 7 is connected via a cable to a mobile generator or the public power grid as an energy source. In this case, a suitable frequency converter must be provided instead of the oscillator 19.

Claims

[1] Method for inductively charging a battery (5) of a motor vehicle (1), comprising a secondary-side energy transfer unit (4) arranged on the underbody, characterized by, that a charging device (2) which is movable and / or movable on a road surface (11) of the motor vehicle (1) and has a primary-side energy transfer unit (7) guided under the underbody (3) of the motor vehicle (1) and electrical energy is transferred from the primary-side energy transfer unit (7) to the secondary-side energy transfer unit (4), wherein a request message requesting and / or planning the charging of the battery (5) by means of the charging device (2) is transmitted to a communication counterpart (16) by means of at least one communication device (15), wherein the request message includes at least one predictive position and / or at least one predictive state of charge of the battery (5) of the motor vehicle (1), wherein the planning information is determined on the basis of a route determined by a navigation system (18) of the motor vehicle (1). [2] Method according to claim 1, characterized by , that the electrical energy is supplied by an electrical energy storage device (9) of the charging device (2) and / or via a connection of the charging device (2) from an external electrical energy source. [3] Method according to claim 1 or 2, characterized by that a motor vehicle-mounted and / or a portable communication device (15) is or will be used to transmit the request message. [4] Method according to any of the preceding claims, characterized by , that the request message includes charge state information describing the current state of charge of the battery (5) and / or position information describing the current position of the motor vehicle (1). [5] Motor vehicle comprising a battery (5) and an underbody-mounted secondary-side inductive energy transfer unit (4) for charging the battery (5), characterized by, that a control device (17) by means of which a requesting and / or planning request message for charging the battery by a charging device (2) which is movable and / or slidable on a road surface (11) of the motor vehicle (1) and has a primary-side energy transfer unit (7) for transferring electrical energy to the secondary-side energy transfer unit (4) can be determined, and a communication device (15) by means of which the request message can be transmitted to a communication counterpart (16) are provided, wherein a navigation system (18) is provided by means of which a route of the motor vehicle (1) can be determined, wherein the request message includes at least one predictive position and / or at least one predictive state of charge of the battery (5) of the motor vehicle (1), which can be determined by the control device (17) on the basis of the route. [6] Motor vehicle according to claim 5, characterized by , that the charging device (2) includes an electrical energy storage device (9) and / or a connection to an external electrical energy source, wherein the electrical energy can be supplied by the energy storage device (9) and / or by the energy source via the connection. [7] Motor vehicle according to claim 5 or 6, characterized by , that the request message includes charge state information describing the current state of charge of the battery (5) and / or position information describing the current position of the motor vehicle (1).

Images