GB2568877A

GB2568877A - A controller, a system, a vehicle and a method

Info

Publication number: GB2568877A
Application number: GB1719663.5A
Authority: GB
Inventors: mcnally Mark
Original assignee: Jaguar Land Rover Ltd
Current assignee: Jaguar Land Rover Ltd
Priority date: 2017-11-27
Filing date: 2017-11-27
Publication date: 2019-06-05
Anticipated expiration: 2037-11-27
Also published as: GB201719663D0; GB2568877B

Abstract

A controller 107 is used to control positioning of a coil 104 for wirelessly recharging a battery 103 of a vehicle 100 (e.g. EV, HEV, BEV, PHEV) via inductive coupling. The controller has a processor configured to obtain a plurality of first measurements, each measurement being indicative of a charging field at the coil at a respective one of plural locations. The controller determines an optimum location at which the first measurement is largest and provides at least one output signal, indicating that movement of the vehicle is required, if the optimum location is outside a target range. A positioning means 106 may be used to position the coil at each of the plural locations. The output signal may be provided to an automated movement system or to a user output device to indicate to the user: a required distance and/or direction of movement of the vehicle; the magnitude of the charging field at the coil when the user moves the vehicle manually; and/or when to stop the vehicle when it is suitably positioned for charging. The controller may receive an input signal from a user input device indicating that charging is to be performed without further movement of the vehicle, whereupon the coil is moved to the optimum location.

Description

The present disclosure relates to a controller, a system, a vehicle and a method. In particular, but not exclusively it relates to a controller, a system, a vehicle and a method for controlling positioning of a coil for wirelessly charging a battery of a vehicle, such as a road vehicle.

Aspects of the invention relate to a controller, a system, a vehicle and a method.

BACKGROUND

It is known to wirelessly charge batteries of an electric vehicle in which a secondary coil mounted on a vehicle receives electrical energy by electromagnetic induction from a primary coil positioned at about ground level. Mechanisms for alignment of the coils have been proposed. A disadvantage of such mechanisms is their inability to correctly determine when the secondary coil cannot be optimally aligned due to incorrect positioning of the vehicle.

It is an aim of the present invention to address disadvantages of the prior art.

SUMMARY OF THE INVENTION

Aspects and embodiments of the invention provide a controller, a system, a vehicle and a method as claimed in the appended claims.

According to an aspect of the invention there is provided a controller for controlling positioning a coil for wirelessly recharging a battery of a vehicle, the controller comprising processing means configured to: obtain a plurality of first measurements, each said first measurement being indicative of a charging field at the coil at a respective one of a plurality of locations; determine a primary one of the locations at which the first measurement is the largest of the first measurements; and provide at least one output signal indicating that movement of the vehicle is required in dependence on the primary location being outside of a target range for the locations.

This provides the advantage that, when a vehicle has a charging coil for wirelessly charging its battery and the vehicle is not positioned in a way that allows an optimum rate of charging to be achieved, the vehicle user or an automated movement system (such as a self-parking system) may be notified to move the vehicle to enable the optimum rate to be achieved.

In some embodiments the locations each have a coordinate in a first direction along the vehicle; and the at least one output signal is configured to indicate that movement of the vehicle is required in the first direction in dependence on the coordinate of the primary location being larger than a coordinate of the target range. This provides the advantage that the user or an automated movement system may be instructed as to which direction the vehicle should be moved in order to allow optimum rate of charging of the battery.

In some embodiments the locations each have a coordinate in a first direction along the vehicle from a first end one of the locations to a second end one of the locations; and the at least one output signal is configured to indicate that movement of the vehicle is required in the first direction in dependence on the primary location being the second end location.

In some embodiments, the coil is only moveable between a first extreme location and a second extreme location and the second end location is at the second extreme location.

In some embodiments the first end location, the first extreme location and the second extreme location each has a coordinate in the first direction, and the coordinate of the first end location is between the coordinate of the first extreme location and the coordinate of the second extreme location.

In some embodiments the first direction is from the rear to the front of the vehicle.

In some embodiments the first direction is from the front to the rear of the vehicle.

In some embodiments the processing means is arranged to provide the at least one output signal to a user output device configured to provide an output indicating that movement of the vehicle is required in dependence on receiving the output signal. This provides the advantage that a user may be informed that movement of the vehicle is required to enable a rate of charging of the battery to be optimized.

In some embodiments the user output device is configured to provide an output for indicating to the user a distance of movement of the vehicle and/or a direction of movement of the vehicle that is required.

In some embodiments the user output device is configured to indicate to the user the magnitude of the charging field at the coil when the user moves the vehicle manually and/or is configured to indicate to the user when to stop the vehicle when the user output device indicates that the vehicle is suitably positioned to charge the battery.

In some embodiments the controller is configured to: receive an input signal from a user input device indicating that charging is to be performed without further movement of the vehicle; and in dependence on receiving the input signal, cause the coil to be moved to said primary one of the locations to enable charging to be performed without further movement of the vehicle.

In some embodiments the processing means is configured to provide the at least one output signal to an automated movement system for causing automated movement of the vehicle. This provides the advantage that the system for causing automated movement may move the vehicle to enable a rate of charging of the battery to be optimized.

In some embodiments the processing means is configured to: obtain a second measurement indicative of a charging field at the coil at each one of a plurality of locations; determine the location in which the second measurement is the largest of the second measurements; and cause the coil to be moved to the location in which the second measurement is the largest of the second measurements.

In some embodiments the processing means is configured to receive a signal indicating that a distance sensed by parking sensors is within a defined range, and to obtain the plurality of measurements in dependence on receiving said signal. This provides the advantage of a higher probability that the primary location is within or close to the target range.

In some embodiments the processing means comprises an electronic memory device having instructions stored therein and an electronic processor configured to access the electronic memory device and execute the instructions stored therein. The processing means may be processing circuitry.

According to another aspect of the invention there is provided a system for positioning a coil for wirelessly recharging a battery of a vehicle, the system comprising processing means according to any one of the previous paragraphs and a positioning means configured to position the coil at each one of the plurality of locations.

In some embodiments the locations are on an arc having an axis extending laterally across the width of the vehicle. This provides the advantage that higher charging rates may be obtained when the coil is positioned within a range of locations that are at or near to a lowest point along the arc. In addition, it allows the coil to be stowed at a higher location along the arc during movement of the vehicle, so that it is less likely to come into contact with a surface on which the vehicle is travelling or an object on that surface.

In some embodiments the processing means is configured to cause the positioning means to return the coil to a stowed location in dependence on the primary location being outside of the target range. This provides the advantage that the coil is less likely to be damaged by collision with an object on the surface on which the vehicle is to be moved.

In some embodiments the system comprises an automated movement system configured to cause movement of the vehicle in response to the at least one output signal being provided. This provides the advantage that the automated movement system may move the vehicle to enable a rate of charging of the battery to be optimized.

According to a further aspect of the invention there is provided a vehicle comprising the controller of any one of the previous paragraphs or the system of any one of the previous paragraphs.

According to yet another aspect of the invention there is provided a method of controlling positioning a coil for wirelessly recharging a battery of a vehicle, the method comprising: obtaining a plurality of first measurements, each said first measurement being indicative of a charging field at the coil at a respective one of a plurality of locations; determining a primary one of the locations at which the first measurement is the largest of the first measurements; and providing at least one output signal indicating that movement of the vehicle is required in dependence on the primary location being outside of a target range for the locations.

In some embodiments the locations each have a coordinate in a first direction along the vehicle, and the method comprises indicating that movement of the vehicle is required in the first direction in dependence on the coordinate of the primary location being larger than a coordinate of the target range.

In some embodiments the locations each have a coordinate in a first direction along the vehicle from a first end one of the locations to a second end one of the locations; and the method comprises indicating that movement of the vehicle is required in the first direction in dependence on the primary location being the second end one of the locations.

In some embodiments the coil is only moveable between a first extreme location and a second extreme location and the second end location is at the second extreme location.

In some embodiments the first end one of the locations, the first extreme location and the second extreme location each has a coordinate in the first direction, and the coordinate of the first end location is between the coordinate of the first extreme location and the coordinate of the second extreme location.

In some embodiments the method comprises providing the at least one output signal to a device for informing a user that movement of the vehicle is required.

In some embodiments the device for informing a user that movement of the vehicle is required provides an output for indicating to the user a distance of movement of the vehicle and/or a direction of movement of the vehicle that is required.

In some embodiments when the user moves the vehicle manually relative to the primary location, the device for informing a user that movement of the vehicle is required will indicate to the user the magnitude of the charging field at the coil as the user moves the vehicle manually and/or will indicate to the user when to stop the vehicle when the device for informing a user that movement of the vehicle is required indicates that the vehicle is suitably positioned to charge the battery.

In some embodiments the method comprises providing the at least one output signal to a system for causing automated movement of the vehicle.

In some embodiments the locations are on an arc having an axis extending laterally across the width of the vehicle.

In some embodiments the method comprises: obtaining a second measurement indicative of a charging field at the coil at each one of a plurality of locations; determining the location in which the second measurement is the largest of the second measurements; and causing the coil to be moved to the location in which the second measurement is the largest of the second measurements.

According to a further aspect of the invention there is provided a controller for positioning a coil for wirelessly recharging a battery of a vehicle, the controller comprising an electronic memory device having instructions stored therein and an electronic processor configured to access the electronic memory device and execute the instructions stored therein such that the processor is operable to: obtain a plurality of first measurements, each said first measurement being indicative of a charging field at the coil at a respective one of a plurality of locations; determine a primary one of the locations at which the first measurement is the largest of the first measurements; and provide at least one output signal indicating that movement of the vehicle is required in dependence on the primary location being outside of a target range for the locations.

This provides the advantage that, when a vehicle has a charging coil for wirelessly receiving electrical energy by electromagnetic induction from a transmission coil and the vehicle is not positioned in a way that allows an optimum rate of charging to be achieved, the vehicle user or an automated movement system (such as a self-parking system) may be notified to move the vehicle to enable the optimum rate to be achieved.

Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

Fig. 1 shows a road vehicle embodying the present invention;

Fig. 2 shows a vehicle embodying the invention in which positioning means comprises one or more arms to which the charging coil is attached;

Fig. 3 shows the vehicle of Fig. 2 but with the charging coil in a deployed position;

Fig. 4 shows a perspective view of the charging coil supported by the arms from the support structure;

Fig. 5 shows a side view of a portion of the support structure and charging coil with the charging coil in a stowed position;

Figs. 6, 7 and 8 each show a side view of the portion of the support structure and charging coil with the charging coil in various deployed positions;

Fig. 9 shows a schematic diagram of a system of the vehicle for positioning the charging coil; Fig. 10 shows a flowchart illustrating a method of controlling positioning of a coil for wirelessly recharging a battery of a vehicle;

Fig. 11 illustrates locations to which a charging coil may be positioned and which have different position coordinates in a direction along the length of the vehicle;

Fig. 12 illustrates locations to which a charging coil may be positioned and which have different position coordinates in a direction along the length of the vehicle;

Fig. 13 shows the same locations as Fig. 12, but with a more limited target range for the locations;

Fig. 14 illustrates locations in which a charging coil may be positioned and which have 2dimensional coordinates; and

Fig. 15 shows a flowchart illustrating a method embodying the present invention.

DETAILED DESCRIPTION

A road vehicle 100 embodying the present invention is shown in Fig. 1. The vehicle 100 comprises an electric motor 101 for driving the vehicle 100 along a road or other ground surface 102. The electric motor 101 is provided with electrical energy that is stored within a battery 103. In order to obtain electrical energy for storage in the battery 103, the vehicle 100 includes a charging coil 104 (or secondary coil) configured to inductively couple with a transmission coil 105 (or primary coil). During a charging process, the transmission coil 105 is supplied with an alternating current which induces an alternating current in the charging coil 104. The alternating current induced in the charging coil 104 is converted to direct current to enable electric charge to be stored in the battery 103.

In the present embodiment, the transmission coil 105 is positioned just below the ground 102, and the charging coil 104 is located on the underside of the vehicle 100.

During charging of the battery 103 the transmission coil 105 generates a charging field. In order for charging of the battery 103 to be as rapid and efficient as possible, the charging coil 104 is required to be positioned to maximize the charging field appearing at the charging coil 104. To enable approximate alignment of the charging coil 104 with the transmission coil 105, the transmission coil 105 may be located at a standardized location. For example, the transmission coil 105 may be located at a standardized location within a marked parking bay of a car park. Therefore, by correct positioning of the vehicle 100 in the parking bay, the charging coil 104 may be approximately correctly positioned with respect to the transmission coil 105. However, in order to optimize the charging field at the charging coil 104, the vehicle 100 includes a system for positioning the charging coil 104 relative to the vehicle 100 and the transmission coil 105. The system comprises a positioning means 106 for positioning the charging coil 104 relative to the vehicle 100 and a positioning controller 107 configured to control the positioning means 106 to move the charging coil 104 between a plurality of different locations and to an optimum location.

To determine the optimum location, the transmission coil 105 may be caused to transmit a test signal while the positioning controller 107 causes the positioning means 106 to move the charging coil 104 between various different locations. A measurement of the received signal at the charging coil 104 is made at each of the different locations and the measurements compared to determine a primary location at which the signal is the largest. If the primary location is within a target range of locations, then the positioning controller 107 moves the charging coil 104 to the primary location and charging of the battery 103 is then started. Alternatively, if the primary location is outside of the target range, then the positioning controller 107 provides an output signal to indicate that movement to the vehicle 100 is required.

The positioning means 106 may comprise a mechanism that only enables movement of the charging coil 104 in one dimension, or it may comprise a mechanism that enables movement of the charging coil 104 in several dimensions. In one embodiment, in which positioning means 106 enables the charging coil 104 to be moved in one dimension only, the charging coil 104 is caused to slide along slides or rails by the operation of a linear actuator. For example, the rails may be positioned to only enable movement along the length of the vehicle 100.

In an alternative embodiment, in which the charging coil 104 is movable by positioning means 106 in two dimensions, the charging coil 104 is mounted on a first set of rails that extend longitudinally along the vehicle 100 and which are mounted on a second set of rails that extend laterally across the vehicle 100. A first linear actuator is provided to move the charging coil 104 longitudinally along the vehicle 100, and a second linear actuator is provided to move the first set of rails, along with the charging coil 104, laterally across the vehicle 100.

A vehicle 100 embodying the invention in which the positioning means 106 comprises one or more arms 201 to which the charging coil 104 is attached, is shown in Figs. 2 and 3. The arms 201 are pivotally attached to a supporting structure 202, such as a subframe of the vehicle 100, to enable the arms 201 to pivot about an axis with respect to the supporting structure 202 to move the charging coil 104 along an arc between a stowed position, as illustrated in Fig. 2, and a deployed position for charging the battery 103, as illustrated in Fig. 3. The arms 201 pivot about axes extending laterally across the width of the vehicle (i.e. into the page in Figs. 2 and 3) and therefore, in this embodiment, the positioning means 106 is configured to move the coil 104 in a first direction along the length of the vehicle and simultaneously in a second direction, i.e. vertical.

In the stowed position of Fig. 2, the charging coil 104 is positioned behind the motor 101 and is relatively high above the ground 102 when compared to deployed positions, such as that illustrated in Fig. 3. Consequently, in the stowed position, the charging coil 104 is relatively safe from impacts with the ground 102, or objects on the ground. However, the deployed positions are closer to the ground, and therefore closer to the height of the transmission coil 105, which generally enables higher charging fields to be detected at the charging coil 104. Also the deployed positions are forward of the stowed position and beneath the motor 101. This allows alignment of the charging coil 104 with the transmission coil 105 when the standardized position of the transmission coil 105 along a parking bay coincides with the position of the motor 101.

The charging coil 104 supported by the arms 201 from the support structure 202 is shown in a perspective view in Fig. 4. The charging coil 104 is located within a charging pad 401 between a first set of arms comprising the arms 201A and 201B and a second set of the arms comprising the arms 201C and 201D.

A first end 402 of each of the first and second arms 201A and 201B is pivotally attached to a first mounting bracket 403A forming a part of the support structure 202 and a second end 404 of those arms 201A and 201B is pivotally attached to the charging pad 401. Similarly, a first end 402 of each of the third and fourth arms 201C and 201D is pivotally attached to a second mounting bracket 403B forming a part of the support structure 202 and a second end 404 of those arms 201C and 201D is pivotally attached to the charging pad 401.

In the present embodiment, the positioning means 106 comprises an electric motor 405 configured to drive a driveshaft 406 via a gear mechanism 407. The first arm 201A is fixed to the driveshaft 402 so that the first arm 201A rotates with the driveshaft 402 when it is driven by the electric motor 405. Thus, the position of the charging coil 104 may be adjusted by operation of the motor 405.

Stowage and deployment of the charging coil 104 is illustrated in Figs. 5, 6, 7 and 8. Fig. 5 shows a side view of a portion of the support structure 202 and the charging coil 104 in a stowed position and Figs. 6, 7 and 8 provide a similar view but with the charging coil 104 in three different deployed positions.

From the stowed position of Fig. 5, the first arm 201A may be pivoted downwards through a first deployed position shown in Fig. 6 to a second deployed position shown in Fig. 7 and through to a third deployed position shown in Fig. 8. The deployed position of Fig. 7 is such that the charging coil 104 is at its lowest possible position relative to the support structure 201. In deployed positions between those of Figs. 6 and 8, the charging coil 104 is only slightly higher than when it is in the deployed position of Fig. 7. However, as the charging coil 104 is moved further forward from its position in Fig. 8, and the arms 201 rotate further away from vertical, the rate at which the charging coil 104 is lifted per additional forward movement increases. Similarly, as the charging coil 104 is moved further back from its position in Fig. 6, and the arms 201 rotate further away from vertical, the rate at which the charging coil 104 is lifted per additional backward movement increases. Consequently, most efficient coupling between the transmission coil 105 and the charging coil 104 may be obtained when the charging coil 104 is within a range of positions neighbouring that of Fig. 7.

A schematic diagram illustrating a system of the vehicle 100 for positioning the charging coil 104 is shown in Fig. 9. The charging coil 104 is positioned by one or more positioning motors 405. In the embodiment of Figs. 2 to 8 the positioning motor 405 may be operated to move the charging coil 104 between the stowed position (shown in Fig. 5) and deployed positions (such as those of Figs. 6 to 8). Alternatively, in embodiments where the charging coil is mounted on horizontal rails or slides, one or more linear actuators comprising positioning motors 405 may be operated to move the charging coil 104 fore and aft and left and right along the vehicle 100.

The positioning motor(s) 405 operates under the control of the positioning controller 107, which in the present embodiment comprises an electronic control unit dedicated to the positioning of the charging coil 104. The electronic control unit comprises a processing means comprising an electronic processor 901 and an electronic memory device 902 having instructions 903 stored therein; the electronic processor 901 being configured to access the electronic memory device 902 and execute the stored instructions 903.

In alternative embodiments, the positioning controller 107 may comprise a software module of an electronic control unit that has another function, such as a battery management system 904. The battery management system 904, amongst other things, may be arranged to control current supplied to the battery 103 from an AC to DC converter 905, which itself is arranged to receive alternating current from the charging coil 104.

In the present embodiment the positioning controller 107 is configured to receive signals from a position sensor 906, associated with the positioning motor 405, which indicates the position of the charging coil 104. In the present embodiment the position sensor 906 comprises a Hall sensor, and the positioning controller 107 monitors the position of the charging coil 104 by monitoring the signals received from the Hall sensor.

The positioning controller 107 is also arranged to receive a signal from a current meter 907. The current meter 907 is configured to measure current induced in the charging coil 104 by the transmission coil 105 and to provide a signal indicative of the measured current to the positioning controller 107. During positioning of the charging coil 104 by the positioning controller 107, the signals provided by the current meter 907 provide an indication of the charging field obtainable at the charging coil 104 at each of various different locations of the charging coil 104.

Although the current meter 907 is shown separately in Fig. 9, it may be included within the battery management system 904.

The positioning controller 107 is configured to provide an output signal on occasions when it determines that movement of the vehicle 100 is required. The output signal may be provided to an automated movement system 909 configured to cause automated movement of the vehicle and/or to a human machine interface (HMI) 912 within the vehicle 100 comprising a user output device 908.

The user output device 908 may comprise a visual output device comprising one or more LEDs (light emitting diodes), or one or more LCDs (liquid crystal displays), or it may comprise an audio output device configured to provide an alarm and/or instructions to a user of the vehicle 100.

The output signal from the positioning controller 107 may be configured to cause the user output device 908 to merely display to the user of the vehicle 100 a direction (forwards or backwards) in which the vehicle 100 should be moved to improve the rate of charging. Alternatively user output device 908 may also be caused to indicate a distance by which the vehicle 100 should be moved. The user is then able to drive the vehicle 100 in the indicated direction and by the suggested distance (when provided).

The HMI 912 of the vehicle 100 may comprise a user input device 913 to enable the user of the vehicle 100 to provide an input to the positioning controller 107 indicating that charging should be performed with the vehicle 100 in its present position. The user input device 913 and the user output device 908 may be provided as a single device, such as a touch screen, or the user input device 913 may comprise a separate device, such as a switch.

In instances when the positioning controller 107 determines that movement of the vehicle 100 should be performed, and causes the user output device 908 to indicate that the vehicle 100 should be moved, the user is able to provide an override signal by operation of the user input device 913, to indicate that charging is to be performed with the current position of the vehicle 100. In dependence on receiving such an input signal, the positioning controller 107 is arranged to cause the coil 104 to be moved to the primary location at which the signal induced in the coil 104 is the largest, to enable charging to be performed without further movement of the vehicle 100.

The automated movement system 909 may be a self-parking system or, in a case where the vehicle 100 is a driverless vehicle, it may be a system configured to drive the vehicle. In dependence on receiving an output signal from the positioning controller 107, the automated movement system 909 may be configured to determine from the output signal a required direction of movement for the vehicle 100 and cause the motor 101 of the vehicle 100 to operate to move the vehicle in the required direction. The distance moved may be a predefined distance (for example 150mm). Alternatively the output signal from the positioning controller 107 may provide an indication of the distance to be moved and the automated movement system 909 may be configured to cause the vehicle 100 to move by the indicated distance.

Alternatively, the vehicle 100 may be a manually controllable vehicle, such as a conventional electric vehicle or an automated vehicle allowing manual control of the vehicle, which requires or allows a user to manually control the vehicle 100 using conventional driver inputs. For example, the motor 101 could be controlled by an accelerator control and brake pedal (not shown).

For a manually controllable vehicle the user output device 908 may indicate to the user that the vehicle 100 is required to move a determined distance and/or in a determined direction.

Once the user output device 908 has indicated or advised the requirement to move the vehicle 100, the user may then manually move the vehicle 100 in the indicated direction and/or the indicated distance as an alternative to the vehicle 100 moving automatically.

In use, the user could be advised the vehicle 100 is required to move further forwards or backwards and subsequently the user may engage a suitable gear and apply acceleration to the vehicle 100. For example, the user may be advised to move the vehicle 100 forwards a further 150mm and the user would be able to manually select a forward gear and apply acceleration to move the vehicle 100. Optionally, the user output device 908 could be able to count down the distance as the vehicle 100 moves, and to display a visual indicator of remaining distance or give an audible indication of remaining distance, to aid the user to achieve a primary location at which the field induced in the coil 104 is the largest. The user output device 908 could be a Human Machine Interface (HMI) screen visible to the user when the user is driving the vehicle 100.

The user output device 908 may indicate to the user the strength or magnitude of the charging field induced in the coil 104, or indicate a value indicative of a strength or magnitude of the charging field induced in the coil 104, when the user moves the vehicle 100 manually.

The user output device 908 may indicate to the user when to stop the vehicle 100 when the indicated strength or magnitude of the charging field induced in the coil 104, or value indicative of a strength or magnitude of the charging field induced in the coil 104, signifies that the vehicle is suitably positioned to charge the battery 103. That is, the user output device 908 may indicate to the user that the vehicle 100 is in a position where the charging field induced in the coil 104 is strong enough to charge the battery 103. The strength or magnitude of the charging field induced in the coil 104, or value indicative of a strength or magnitude of the charging field induced in the coil 104, where the user will be indicated to stop may depend on a predetermined threshold for the strength or magnitude of the charging field induced in the coil 104.

The positioning controller 107 may be arranged to receive a signal from a parking distance control (PDC) system 910, which comprises parking sensors 911. The PDC system 910 may be configured to provide a signal indicating the distance from the vehicle 100 to a front edge of a parking bay or a signal indicating that said distance is within a defined range. For example, in an embodiment the defined range is 0 mm to 300 mm.

The purpose of the signals provided by the PDC system 910 and the current meter 907 to the positioning controller 107, and the signals provided by the positioning controller 107 to the user output device 908 and/or automated movement system 909, will be further explained below with reference to Figs. 10 to 15.

A method 1000 of controlling positioning of a coil 104 for wirelessly recharging a battery 103 of a vehicle 100 is illustrated by the flowchart of Fig. 10. The method 1000 may be performed by a controlling means such as the positioning controller 107. At block 1001 of the method 1000, a plurality of measurements is obtained, and each of the measurements is indicative of a charging field at the charging coil 104 at a respective location. For example, Fig. 11 illustrates locations to which a charging coil 104 may be positioned and which have different position coordinates in a direction (illustrated by arrow 1101), along the length of the vehicle 100. In the present example, there are 28 different locations with coordinates 1 to 28, but it will be appreciated that more or less than 28 coordinates may be used. In an example, of the process at block 1001, while the transmission coil 105 emits a charging field, the positioning controller 107 controls a positioning means 106 to position the charging coil 104 at each of the locations and obtains a measurement indicative of the charging field at the charging coil 104 from the current meter 907 at each of the locations.

At block 1002 of the method, a primary one of the locations at which the measurement is the largest of the measurements is determined. In the simple example where measurements are made at all of the locations, the process at block 1002 comprises determining which of the locations provided the largest measurement. However, because the measurements generally rise to a maximum and then fall as the charging coil 104 moves in the direction 1101 along the length of the vehicle 100, the processes of blocks 1001 and 1002 may be performed more efficiently by combining them in a search process. For example, the positioning controller 107 may control the positioning means 106 to move the charging coil 104 at sequential locations along the direction 1101, obtain a measurement at each one of the sequential locations and determine the largest of the measurements by detecting when a maximum has occurred. For example, if measurements are made at the locations in the order of their coordinates (1 to 28) and the measurements show increasing charging field from position coordinates 1 to 8 and then a decrease in charging field from position coordinate 8 to position coordinate 9 then it may be determined at block 1002 that the location with coordinate 8 is the primary location without obtaining measurements for the remaining locations.

In alternative examples of the method 1000, the processes at blocks 1001 and 1002 may be further expedited by performing several search processes with decreasing movements in each search process. For example, a first search may be performed in which the charging coil 104 is only moved to locations with even numbered coordinates to determine the even numbered location with the largest measurement, and then a second search may be performed that includes odd numbered locations neighbouring the even numbered location with the largest measurement. Alternatively, the searching process may be a binary search started at a location having a middle coordinate value. For example, with reference to FIG. 11, measurements may be firstly obtained for locations with coordinates 14 and 15 to determine whether the primary location is in the range 15 to 28 or in the range 1 to 14. If, for example it is determined that the primary location is in the range 15 to 28, measurement may then be made at locations 21 and 22 to determine if the primary location is in the range 15 to 21 or in the range 22 to 28, and so on.

After determining the primary location at block 1002, at block 1003 the method 1000 comprises providing at least one output signal indicating that movement of the vehicle 100 is required in dependence on the primary location being outside of a target range for the locations. The target range for the locations are typically predefined for the positioning means 106 of a charging coil 104. For example, in an embodiment where the positioning means 106 comprises rails or slides to enable the charging coil 104 to be moved horizontally backwards and forwards along the vehicle 101, the target range may be all locations except the extreme forward and rearward locations between which the charging coil 104 is moveable. The extreme locations are not included in the target range because, if the primary location is one of the extreme locations, it suggests that the largest charging field detected at the charging coil 104 could have been even larger if the vehicle 100 had been positioned differently. For example, the charging coil 104 may be moveable between all positions between, and including, a first end location with coordinate 1 in Fig. 11, and a second end location with coordinate 28. In this case the target range may be all locations with coordinates 2 to 27 inclusive, and the output signal is only provided at block 1003 when the primary location has a coordinate of 1 or 28. If the primary location is the end location (with coordinate 28 in this example) closest to the front of the vehicle 100, the output signal may indicate that forward movement of the vehicle 100 is required. Similarly if the primary location is an end location (with coordinate 1 in this example) closest to the rear of the vehicle 100, the output signal may indicate that backwards movement of the vehicle 100 is required.

In the example where the positioning means is as described with reference to Figs. 2 to 8, the charging coil 104 may be moved between the stowed position and several different deployed positions. However, the measurements at block 1001 are only performed at the deployed positions. For example, Fig. 12 illustrates locations to which a charging coil 104 may be positioned and which have different position coordinates in a direction (illustrated by arrow 1201), along the length of the vehicle 100 of Fig. 2. In this example, there are 28 different deployment locations with coordinates 1 to 28, but it will be appreciated that more or less than 28 locations may be used. The process to determine the primary location may be as described above and the output signal may be provided at block 1003 only when the primary location is determined at block 1002 to be the first end location, with coordinate 1 or the second end location, with coordinate 28. In this example, the first end location, with coordinate 1, is not an extreme position to which the charging coil 104 may be moved, because the charging coil 104 may be moved backwards past the first end location to the stowed position.

In arrangements such as that of Figs. 2 to 8 where the charging coil 104 moves upwards as it is moved forwards or backwards from central locations to extreme locations, it may be expected that the highest rates of charging of the battery 103 may be obtained when the charging coil 104 is at or close to its lowest position, as shown in Fig. 7. Consequently the target range for the locations of the charging coil 104 may be limited to locations that are relatively close to the lowest position. This situation is illustrated in Fig. 13, which shows the same locations as Fig. 12, but with a more limited target range for the locations. In this example, the charging coil 104 may be deployed to any one of the 28 locations with coordinates 1 to 28, but if the primary location is determined at block 1003 of the method to be outside of the target range 7 to 22, then an output signal is provided indicating that movement of the vehicle is required.

If the primary location has a coordinate that is greater than the coordinates of the target range (i.e. greater than 22 in this example), then the output signal may simply indicate that forward movement of the vehicle 100 is required. Similarly, if the primary location has a coordinate that is less than the coordinates of the target range (i.e. less than 7 in this example), then the output signal may simply indicate that backwards movement of the vehicle 100 is required. However, in an embodiment, a distance to be moved may be determined from the coordinate of the primary location, and the output signal may also indicate the distance to be moved. For example, a first distance to be moved may be indicated by the output signal when the primary location has a coordinate of 28 and a comparatively small second distance to be moved may be indicated when the primary location has a coordinate of 23.

In an embodiment in which the charging coil 104 is moveable laterally across the vehicle 100 as well as forwards and backwards, measurements may be made to determine 2dimensional coordinates of a primary location. For example, Fig. 14 illustrates locations in which a charging coil 104 may be positioned and which have 2-dimensional coordinates identifying the locations in an x-direction (illustrated by arrow 1401), along the length of the vehicle 100 of Fig. 1, and in a y-direction (illustrated by arrow 1402) from right to left of the vehicle. In embodiments where the charging coil 104 is moveable in two dimensions, the method 1000 of Fig. 10 may be applied to just one dimension, such as backwards and forwards. In such an embodiment, the output signal may indicate that a forward or backward movement of the vehicle is required, if the primary location determined at block 1002 has an x-coordinate that is outside of a target range of x-coordinates. However, in the example of Fig. 14 the target range 1403 of locations is 2-dimensional and extreme forward and rear locations as well as extreme left and right locations are outside of the target range. Thus at block 1003 of the method 1000, the output signal may indicate that movement left or right and/or forward or backwards is required.

In order to determine the primary location, measurements may be made while the position of the charging coil 104 is varied in the x-direction, while keeping constant its position in the ydirection. Having determined an x-coordinate corresponding to a largest measurement, the charging coil may be moved to a location having that x-coordinate. Further measurements may then be made while the position of the charging coil 104 is varied in the y-direction, keeping the position in the x-direction constant. The location where the largest of the further measurements is made is then determined to be the primary location.

In each example, the output signal may be provided at block 1003 to an automated movement system 909 and/or a user output device 908 and no further action taken until the vehicle 100 has been moved by the user or by the automated movement system 909. After such movement the processes at blocks 1001 and 1002 may be repeated to obtain second measurements at a plurality of the locations and if the primary location is determined to be in the target range, the charging coil 104 is moved to the primary location and charging of the battery is started.

An embodiment of the method 1000 is illustrated by the flowchart shown in Fig. 15. Optionally, at block 1501, the method 1000 may comprise receiving a signal indicative of a distance sensed by parking sensors, for example from the PDC system 910 of Fig. 9, and enabling the charging process in dependence on receiving a signal indicating that the vehicle 100 is positioned correctly in a parking bay. For example, the PDC system 910 may provide a signal confirming that the front of the vehicle 100 is positioned within a tolerance range of distances from the front of a parking bay. In addition, or alternatively, the parking bay may be provided with a wireless system for detecting the position of the vehicle within the parking bay, for example by triangulation or trilateration, and provide a signal to the vehicle indicating that the vehicle is correctly positioned in the parking bay in dependence on the detected position. For example, the parking bay may include wireless LAN (local area network) based positioning technology (i.e. a Wi-Fi positioning system) configured to detect the position of a transceiver on the vehicle. Alternatively, the presence of the vehicle within the parking bay may be determined by an RFID (radio frequency identification) real time locating system. For example, such a system may comprise ultra-wideband active RFID modules to provide accurate verification of the position of the vehicle in the parking bay.

Following the process at block 1501, processes at blocks 1001 and 1002 are performed as described above in regard to Fig. 10. At block 1502 it is determined whether the primary location is outside of a target range of the locations. If it is determined at block 1502 that the primary location is outside of the target range, then the process at block 1504 is performed. Optionally a process at block 1503 may be performed before the process at block 1504. At block 1503 the charging coil 104 is caused to be moved back to its stowed position. This process may be performed in embodiments such as the one illustrated in Figs. 2 to 8, in which deployed positions of the charging coil 104 are lower than a stowed position. In this way, the charging coil 104 may be protected from accidental collision with an object on the ground in the path of the vehicle.

At block 1504 at least one output signal is provided indicating that movement of the vehicle 100 is required. The one or more output signals may be provided to the user output device 908 or to the automated movement system 909 as described above with regard to Figs. 9 and 10.

At block 1505, it is determined whether the vehicle 100 has been repositioned and if it has not then the process at block 1505 is repeated. If it is determined that the vehicle has been repositioned (either by the user or an automated movement system 909) then the processes at blocks 1001, 1002 and 1502 are repeated in respect of second measurements of the charging field at the charging coil 104. If it is determined again, at block 1502, that the primary location is outside of the target range, then the processes at blocks 1503, 1504 and 1505 may be repeated.

If it is determined at block 1502 that the primary location is not outside of the target range, then the charging coil 104 is moved to the primary location at block 1505 and charging of the battery is enabled. For example, the positioning controller 107 may provide a signal to the battery management system 904 indicating that charging of the battery may be started.

For purposes of this disclosure, it is to be understood that the controller(s) described herein can each comprise a control unit or computational device having one or more electronic processors. A vehicle and/or a system thereof may comprise a single control unit or electronic controller or alternatively different functions of the controller(s) may be embodied in, or hosted in, different control units or controllers. A set of instructions could be provided which, when executed, cause said controller(s) or control unit(s) to implement the control techniques described herein (including the described method(s)). The set of instructions may be embedded in one or more electronic processors, or alternatively, the set of instructions could be provided as software to be executed by one or more electronic processor(s). For example, a first controller may be implemented in software run on one or more electronic processors, and one or more other controllers may also be implemented in software run on or more electronic processors, optionally the same one or more processors as the first controller. It will be appreciated, however, that other arrangements are also useful, and therefore, the present disclosure is not intended to be limited to any particular arrangement. In any event, the set of instructions described above may be embedded in a computerreadable storage medium (e.g., a non-transitory computer-readable storage medium) that may comprise any mechanism for storing information in a form readable by a machine or electronic processors/computational device, including, without limitation: a magnetic storage medium (e.g., floppy diskette); optical storage medium (e.g., CD-ROM); magneto optical storage medium; read only memory (ROM); random access memory (RAM); erasable programmable memory (e.g., EPROM ad EEPROM); flash memory; or electrical or other types of medium for storing such information/instructions.

The blocks illustrated in the Figs. 10 and 15 may represent steps in a method and/or sections of code in the computer program 903. The illustration of a particular order to the blocks does not necessarily imply that there is a required or preferred order for the blocks and the order and arrangement of the block may be varied. Furthermore, it may be possible for some steps to be omitted.

Although embodiments of the present invention have been described in the preceding paragraphs with reference to various examples, it should be appreciated that modifications to the examples given can be made without departing from the scope of the invention as claimed.

Features described in the preceding description may be used in combinations other than the 5 combinations explicitly described.

Although functions have been described with reference to certain features, those functions may be performable by other features whether described or not.

Although features have been described with reference to certain embodiments, those features may also be present in other embodiments whether described or not.

Whilst endeavoring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant 15 claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

1. A controller for controlling positioning a coil for wirelessly recharging a battery of a vehicle, the controller comprising processing means configured to:

obtain a plurality of first measurements, each said first measurement being indicative of a charging field at the coil at a respective one of a plurality of locations;

determine a primary one of the locations at which the first measurement is the largest of the first measurements; and provide at least one output signal indicating that movement of the vehicle is required in dependence on the primary location being outside of a target range for the locations.

2. The controller according to claim 1, wherein: the locations each have a coordinate in a first direction along the vehicle; and the at least one output signal is configured to indicate that movement of the vehicle is required in the first direction in dependence on the coordinate of the primary location being larger than a coordinate of the target range.

3. The controller according to claim 1 or claim 2, wherein: the locations each have a coordinate in a first direction along the vehicle from a first end one of the locations to a second end one of the locations; and the at least one output signal is configured to indicate that movement of the vehicle is required in the first direction in dependence on the primary location being the second end location.

4. The controller according to claim 3, wherein the coil is only moveable between a first extreme location and a second extreme location and the second end location is at the second extreme location.

5. The controller according to claims 3 or claim 4, wherein the first end location, the first extreme location and the second extreme location each has a coordinate in the first direction, and the coordinate of the first end location is between the coordinate of the first extreme location and the coordinate of the second extreme location.

6. The controller according to any one of claims 2 to 5, wherein the first direction is from the rear to the front of the vehicle.

7. The controller according to any one of claims 2 to 5, wherein the first direction is from the front to the rear of the vehicle.

8. The controller according to claims 1 to 7, wherein the processing means is arranged to provide the at least one output signal to a user output device, the user output device being configured to provide an output for indicating to a user that movement of the vehicle is required, in dependence on receiving the output signal.

9. The controller according to claim 8, wherein the user output device is configured to provide an output for indicating to the user a distance of movement of the vehicle and/or a direction of movement of the vehicle that is required.

10. The controller according to claim 9, wherein the user output device is configured to indicate to the user the magnitude of the charging field at the coil when the user moves the vehicle manually and/or is configured to indicate to the user when to stop the vehicle when the user output device indicates that the vehicle is suitably positioned to charge the battery.

11. The controller according to any of claims 8, 9, or 10, wherein the controller is configured to: receive an input signal from a user input device indicating that charging is to be performed without further movement of the vehicle; and in dependence on receiving the input signal, cause the coil to be moved to said primary one of the locations to enable charging to be performed without further movement of the vehicle.

12. The controller according to claims 1 to 11, wherein the processing means is configured to provide the at least one output signal to an automated movement system for causing automated movement of the vehicle.

13. The controller according to claims 1 to 12, wherein the processing means is configured to:

obtain a second measurement indicative of a charging field at the coil at each one of a plurality of locations;

determine the location in which the second measurement is the largest of the second measurements; and cause the coil to be moved to the location in which the second measurement is the largest of the second measurements.

14. The controller according to claims 1 to 13, wherein the processing means is configured to receive a signal indicating that a distance sensed by parking sensors is within a defined range, and to obtain the plurality of measurements in dependence on receiving said signal.

15. The controller according to claims 1 to 14, wherein the processing means comprises an electronic memory device having instructions stored therein and an electronic processor configured to access the electronic memory device and execute the instructions stored therein.

16. A system for positioning a coil for wirelessly recharging a battery of a vehicle, the system comprising processing means according to any one of claim 1 to 13 and a positioning means configured to position the coil at each one of the plurality of locations.

17. A system according to claim 16, wherein the locations are on an arc having an axis extending laterally across the width of the vehicle.

18. A system according to claim 16 or claim 17, wherein the processing means is configured to cause the positioning means to return the coil to a stowed location in dependence on the primary location being outside of the target range.

19. A system according to any one of claims 16 to 18, wherein the system comprises an automated movement system configured to cause movement of the vehicle in response to the at least one output signal being provided.

20. A vehicle comprising the controller of any one of claims 1 to 15 or the system of any one of claims 16 to 19.

21. A method of controlling positioning a coil for wirelessly recharging a battery of a vehicle, the method comprising:

obtaining a plurality of first measurements, each said first measurement being indicative of a charging field at the coil at a respective one of a plurality of locations;

determining a primary one of the locations at which the first measurement is the largest of the first measurements; and providing at least one output signal indicating that movement of the vehicle is required in dependence on the primary location being outside of a target range for the locations.

22. The method according to claim 21, wherein the locations each have a coordinate in a first direction along the vehicle, and the method comprises indicating that movement of the vehicle is required in the first direction in dependence on the coordinate of the primary location being larger than a coordinate of the target range.

23. The method according to claim 21 or claim 22, wherein: the locations each have a coordinate in a first direction along the vehicle from a first end one of the locations to a second end one of the locations; and the method comprises indicating that movement of the vehicle is required in the first direction in dependence on the primary location being the second end one of the locations.

24. The method according to claim 23, wherein the coil is only moveable between a first extreme location and a second extreme location and the second end location is at the second extreme location.

25. The method according to claims 23 or claim 24, wherein the first end one of the locations, the first extreme location and the second extreme location each has a coordinate in the first direction, and the coordinate of the first end location is between the coordinate of the first extreme location and the coordinate of the second extreme location.

26. The method according to any one of claims 22 to 25, wherein the first direction is from the rear to the front of the vehicle.

27. The method according to any one of claims 22 to 25, wherein the first direction is from the front to the rear of the vehicle.

28. The method according to claims 21 to 27, wherein the method comprises providing the at least one output signal to a device for informing a user that movement of the vehicle is required.

29. The method according to claim 28, wherein the device for informing a user that movement of the vehicle is required provides an output for indicating to the user a distance of movement of the vehicle and/or a direction of movement of the vehicle that is required.

30. The method according to claim 29, wherein when the user moves the vehicle manually relative to the primary location, the device for informing a user that movement of the vehicle is required will indicate to the user the magnitude of the charging field at the coil as the user moves the vehicle manually and/or will indicate to the user when to stop the vehicle when the device for informing a user that movement of the vehicle is required indicates that the vehicle is suitably positioned to charge the battery.

31. The method according to claims 21 to 29, wherein the method comprises providing the at least one output signal to a system for causing automated movement of the vehicle.

32. The method according to claims 21 to 31, wherein the locations are on an arc having an axis extending laterally across the width of the vehicle.

33. The method according to claims 21 to 32, wherein the method comprises:

obtaining a second measurement indicative of a charging field at the coil at each one of a plurality of locations;

determining the location in which the second measurement is the largest of the second measurements; and causing the coil to be moved to the location in which the second measurement is the largest of the second measurements.

34. A controller, a system, a vehicle or a method as disclosed herein with reference to the accompanying figures.