Electric vehicle and method of recharging such an electric vehicle

Abstract

TITLE: Electric Vehicle and Method for Charging Such an Electric Vehicle The electric vehicle (1) includes an on-board detection system (5), configured to secure a static charging system (2) upon detection of an object within a predetermined area. The on-board detection system (5) comprises a primary pattern generator, a light beam emitter (9) dependent on a primary pattern, a light beam detector (11), a pattern analyzer configured to extract a secondary pattern from the light beam, a pattern comparator, and an on-board control unit (13). This on-board control unit (13) is configured to disconnect the grounding and control the activation of the static charging system (2) if and only if the primary pattern is time-varying and the primary and secondary patterns are equal for a predetermined minimum duration. Figure for the abstract: Figure 1

Description

Title of the invention: Electric vehicle and method for recharging such an electric vehicle

[0001] The present invention relates to an electric vehicle and a method of recharging such an electric vehicle.

[0002] It is known to use a static charging system to recharge an electric vehicle, particularly a bus, while stationary. Charging takes place when the vehicle is stopped, either on the route or at the depot, by covering a buried portion of the static charging system. In the case of a bus or other wheeled vehicle, the ground clearance is approximately 30 centimeters. Therefore, there is a risk of accidental contact by a person with live parts when the bus is positioned near the static charging system, and thus of electrocution, particularly on the road side, where the negative and positive terminals of the buried portion of the static charging system are generally located, with the grounding terminal positioned on the sidewalk or platform side.Currently, mechanical systems are used, establishing a temporary physical barrier on the ground between the static charging system and the outside, thus preventing accidental contact with it and therefore electrocution.

[0003] Patent application DE102011109532A also discloses the possibility of setting up a virtual barrier, delimiting a danger zone, in which the intrusion of an external object triggers the interruption of the load.

[0004] Solutions involving mechanical ground barriers require cumbersome and costly infrastructure. As for virtual barrier solutions, their reliability and robustness depend on their technical implementation, which is not detailed in the prior art and can be complex. However, the reliability and robustness of the detection system are of great importance to meet the specific safety requirements of the described use case.

[0005] The aim of the invention is therefore to propose an electric vehicle that provides protection against the risk of electrocution by detecting the approach of an object, which is both sufficiently reliable and robust to meet the specific safety requirements of the use case and less costly and intrusive on the roadway than existing mechanical barriers.

[0006] To this end, the invention relates to an electric vehicle configured to be recharged by means of a static charging system and including an on-board detection system, the detection system being configured to control the interruption of the electrical current supply and the grounding of the system static recharging in case of detection of an object in a predetermined area, characterized in that the on-board detection system comprises:

[0007] - a time-varying primary pattern generator,

[0008] - an emitter of a light beam dependent on a primary pattern, generated by the primary pattern generator,

[0009] - a light beam detector,

[0010] - a pattern analyzer, configured to extract a secondary pattern from the beam light detected by the light beam detector,

[0011] - a pattern comparator, configured to compare the primary pattern and the pattern secondary and to verify that the primary pattern is variable as a function of time,

[0012] - an on-board control unit, configured to suppress grounding and The static charging system will be powered on if and only if the pattern comparator detects that:

[0013] a) the primary motif is variable over time, and

[0014] |3) the primary and secondary motives are equal for a minimum duration predetermined.

[0015] Thanks to the invention, the arrival of an object in a danger zone surrounding the buried part of the static charging system can be detected without additional installation on the roadway. Indeed, the presence of an object in the path of the light beam alters the image of the light beam on the ground, and therefore the secondary pattern relative to the primary pattern. This is detected by the comparator and can be used to interrupt the power supply to a buried part of the static charging system, thus eliminating any risk of electrocution. The use of a predetermined detection zone, including the charging system, as well as the time-varying nature of the primary pattern, ensures the reliability and robustness of the protection system.

[0016] According to other advantageous aspects of the invention, the electric vehicle comprises one or more of the following features, taken individually or in all technically possible combinations:

[0017] - the primary pattern generator, the pattern analyzer and the pattern comparator belong to the same electronic control system, including the same electronic board or the same programmable electronic controller;

[0018] - the emitter is a light beam projector and the beam detector luminous is a camera;

[0019] - a minimum distance between the charging system and a design formed on the ground by the light beam is greater than the product between, on the one hand, a deactivation time of the static charging system and, on the other hand, a predetermined speed of movement;

[0020] - the primary pattern varies with a frequency of variation between 1Hz and 20Hz, preferably in the range of 10Hz;

[0021] - the predetermined minimum duration is between 85% and 95% of a period of variation of the pattern, preferably equal to about 90% of the period of variation of the pattern.

[0022] The invention also relates to a method of recharging an electric vehicle on a static charging system according to the foregoing, the method comprising at least the following steps, consisting of:

[0023] a) activate the primary pattern generator;

[0024] b) transmit the primary pattern to the pattern comparator;

[0025] c) emit, by means of the emitter, the light beam depending on the primary pattern generated by the pattern generator;

[0026] d) acquire an image of a drawing formed by the light beam, by means of the light beam detector;

[0027] e) extract a secondary pattern from a signal representative of the image acquired in step d), using the pattern analyzer;

[0028] f) transmit the secondary pattern to the pattern comparator;

[0029] g) compare the primary and secondary patterns and verify that the primary pattern is variable over time using the pattern comparator;

[0030] h) disconnect the grounding and switch on the static charging system, using the on-board control unit, if and only if step g) reveals that:

[0031] a) the primary motif is variable over time, and

[0032] |3) the primary and secondary motives are equal for a minimum duration predetermined.

[0033] According to other advantageous aspects of the invention, the method comprises one or more of the following features, taken individually or in all technically possible combinations: - during step c), the light beam is projected onto the ground, along the electric vehicle, between an area accessible to the public and the static charging system; - the primary pattern and the secondary pattern are each a numerical code that varies according to time.

[0034] The invention will become clearer upon reading the following description, given solely by way of non-limiting example, and made with reference to the drawings in which: - [Fig.1] [Fig.1] is a perspective view of an electric vehicle according to the invention; - [Fig.2] [Fig.2] is a functional diagram of a detection device belonging to the electric vehicle of [Fig.1].

[0035] The electric bus 1 shown in [Fig. 1] transports passengers from one stop to another along a bus route and is stored at the end of its service in a depot. A charging station for the electric bus 1 is defined as one of the stops on the route or the depot.

[0036] The invention is not limited to the bus but relates to any electric vehicle, preferably a land vehicle for public transport such as a bus, train, tram or metro.

[0037] The electric bus 1 is electrically recharged at each charging station by means of a static charging system 2, comprising, among other things, an underground part which includes fixed terminals 3, as well as mobile on-board terminals, arranged under the electric bus 1. The fixed terminals 3 include a negative terminal 31, a positive terminal 33 and an earth terminal 35. A circuit 21, belonging to the underground part of the static charging system 2, makes it possible to apply a voltage between the negative terminals 31 and positive terminals 33. The circuit 21 includes a voltage source 23, a power-on switch 25, the negative terminals 31 and positive terminals 33, the earth terminal 35, an earthing electrode 29 electrically connected to the earth terminal 35 and two earthing switches 28 making it possible to connect or disconnect the negative terminals 31 and positive terminals 33 to earth.A control unit 27 controls the opening and closing of the power-on switch 25 and the grounding switches 28.

[0038] The electric bus 1 is of the type operating in continental Europe, on the right-hand side of the roadway, in a lane V preferably dedicated to public transport. In [Fig. 1], the arrow D represents the direction of travel of the electric bus 1 forward in lane V. A sidewalk T is located to the right of the electric bus 1, while a road R runs alongside lane V, to its left in the direction of travel of the electric bus 1.

[0039] Within the buried section, the negative terminal 31 is furthest from the sidewalk T, the grounding terminal 35 is closest to the sidewalk T, and the positive terminal 33 is located at a distance from the sidewalk T intermediate between the distances of the negative and grounding terminals from that sidewalk. The grounding terminal 35 is therefore closest to an area where passersby or pedestrians usually stand, thus limiting the risk of a person coming into contact with one of the positive and negative terminals, which are further from the sidewalk T.

[0040] Let G be the ground clearance of the electric bus 1, which is approximately 30 cm. On the left side, at the front or at the rear of the electric bus 1, access to a space located between the floor of the electric bus 1 and the track V is possible over the entire height of The ground clearance G. On the side of the curb T, i.e. on the right side of the electric bus 1, the apparent ground clearance is reduced due to the height of the curb T. The risk of a child, animal or electrically conductive object entering the aforementioned volume is therefore maximum on the front, rear or left side and minimum on the right side of the electric bus 1.

[0041] Therefore, a detection device 5 is mounted on the electrical bus 1 to detect any intrusion into the volume located below the electrical bus 1, preferably from its left side. Alternatively, the detection device 5 can be installed on the front of the electrical bus 1.

[0042] The detection device 5, shown in more detail in [Fig. 2], comprises an electronic control unit 7, a transmitter 9, a light beam detector 11, and an onboard control element 13. The transmitter 9 is preferably a light beam projector, for example, in a wavelength range of the visible or infrared spectrum. The light beam detector 11 is preferably a camera. The onboard control element 13 is configured to communicate with the control element 27 of the circuit 21.

[0043] The electronic control assembly 7 itself comprises a primary pattern generator 15, communicating with the emitter 9, a pattern analyzer 17, communicating with the light beam detector 11, and a pattern comparator 19, communicating with the primary pattern generator 15, the pattern analyzer 17 and the control unit 13.

[0044] The three parts 15, 17 and 19 of the electronic control assembly 7 can be distinct physical entities, distinct components mounted on the same electronic board or software building blocks integrated into a programmable electronic controller.

[0045] The generator 15 is configured to generate a time-varying numeric code, which constitutes a primary pattern M15. The code can, for example, be a succession of 0s and 1s.

[0046] Advantageously, the primary pattern M15 varies periodically with time, and its frequency is denoted fl5 and its period T15. Advantageously, the frequency fl5 is between 1 Hz and 20 Hz, preferably on the order of 10 Hz. Alternatively, depending on the technology used to generate the primary pattern, the frequency range of fl5 may be different.

[0047] The primary pattern M15 generated by the primary pattern generator 15 is supplied as input to the emitter 9, which emits a light beam F9 towards the ground and along the left side of the electric vehicle 1. The light beam F9 depends on the primary pattern M15 and varies with time like this primary pattern. By default, the light beam F9 forms a pattern DI5 on a ground detection area. which is an image of the primary pattern M15. In particular, the design D15 is variable over time, just like the primary pattern M15.

[0048] The detector 11 is oriented towards the area where the design D15 is formed when the transmitter 9 is in operation. Advantageously, the viewing axis Vil of the camera constituting the detector 11 is directed towards this area. Thus, the camera makes it possible to detect the design D15 and to generate a video signal S11 comprising information relating to the design D15 and transmitted by the detector 11 to the pattern analyzer 17. In particular, the video signal S11 includes information relating to a variable secondary pattern M'15 integrated into the design D15 detected by the camera.

[0049] In principle, in the absence of a malfunction of the detection device 5, the variable secondary pattern M' 15 corresponds to the image of the variable secondary pattern M15 formed on the ground in drawing D15 as detected by the camera 11 in said drawing. More precisely, in the absence of disturbances in the detection zone, the variable secondary pattern M' 15 is identical to the variable secondary pattern M15.

[0050] The pattern analyzer 17 is configured to extract the secondary pattern M' 15 from the video signal SI 1, using an image processing technique.

[0051] The generator 15 continuously supplies the comparator 19 with the variable primary pattern M15 that it generates. On the other hand, the analyzer 17 continuously supplies the comparator 19 with the variable secondary pattern M'15 that it extracts from the video signal SU.

[0052] Thus, comparator 19 can compare the primary variable pattern M15 and the secondary variable pattern M'15 at any time. Furthermore, comparator 19 is configured to verify that the primary pattern M15 it receives is indeed time-varying, in particular that it is not fixed.

[0053] The comparator 19 can also be described as a "safety voter" because it ensures the equality of the primary motive M15 and secondary motive M'15, which corresponds to a safe operation of the electric vehicle 1, as can be seen from the explanations that follow.

[0054] The comparator 19 is configured to send to the on-board control unit 13 an S19 signal to activate or deactivate the power supply of the static charging device.

[0055] We denote dl the minimum distance measured between, on the one hand, the drawing D15 formed on the road R and, on the other hand, the nearest fixed marker to this drawing, in the example the negative fixed marker 31.

[0056] The implementation of a recharging method for the electric bus 1 is described below.

[0057] When stopped at a charging station, the electric bus 1 covers the buried part of the static charging system 2 and can be charged. In [Fig. 1], the part buried is shown at the front of electric bus 1 for explanatory purposes but, in reality, the mobile terminals on board electric bus 1 are above the fixed terminals 3 when stopped at the charging station.

[0058] The primary pattern generator 15 is activated to generate the time-varying primary pattern M15, preferably in the form of a digital code. The primary pattern M15 is then transmitted to the comparator 19 and to the emitter 9, which then emits the light beam F9 including the primary pattern M15. Since the primary pattern M15 is time-varying, the light beam F9 is animated over time, as is the pattern D15. The light beam F9 forms the pattern D15 on the projection surface, which is preferably a strip on the ground parallel to the vehicle on the road side R, or alternatively at the front of the vehicle, and which delimits a detection zone containing the fixed terminals 3 and the mobile on-board terminals of the static charging system.

[0059] An image of the drawing D15 is acquired by means of the detector 11, this image being variable over time, like the primary pattern M15. This image is then transmitted to the pattern analyzer 17 within the video signal SU. In other words, the video signal SI1 is representative of the drawing D15 acquired by the camera forming the detector 11. The pattern analyzer 17 extracts a secondary pattern M'15 from this video signal SI1, using image processing techniques, and then transmits this pattern to the comparator 19.

[0060] Comparator 19 satisfies two conditions, namely:

[0061] a) Is the primary motif M15 variable over time?

[0062] |3) Are the primary motif M15 and secondary motif M'15 identical?

[0063] To take into account a possible time lag between the transmission of the primary pattern M15 by the generator 15 to the comparator 19 and the transmission of the secondary pattern M'15 by the analyzer 17 to the comparator 19 after image processing, it is provided that condition |3) is deemed to be satisfied if the primary pattern M15 and secondary pattern M'15 are identical over a predetermined minimum duration, preferably between 85% and 95% of the period T15, preferably equal to 90% of the period T15.

[0064] Alternatively, a possible time lag between the transmissions of the primary motif M15 and secondary motif M'15 is taken into account by using another approach.

[0065] Alternatively, the predetermined minimum duration is equal to 100% of the period T15 or does not depend on this period. It can, for example, be set at 1 second.

[0066] If and only if both conditions a) and |3) are met, the signal S19 authorizes, via the on-board component 13, the closure of the control component 27, allowing the power-on switch 25 to remain in the closed position and the maintenance in open position of the grounding switches 28 and thus energize the fixed negative terminals 31 and positive terminals 33 of the static charging system, allowing the charging of the electric bus 1 after contacting the fixed terminals 3 and the mobile terminals of the static charging system.

[0067] The charge can continue as long as these two conditions a) and |3) are met.

[0068] In the event that the primary pattern M15 ceases to vary over time, for example due to a fault in the transmitter 15, condition a) is no longer met. In this case, the signal S19 activates the on-board control unit 13 so that it drives the control unit 27 to open the power-on switch 25 and ground the fixed negative terminals 31 and positive terminals 33 by closing the grounding switches 28 and thus cut off the power supply to the fixed negative terminals 31 and positive terminals 33 of the static charging system 2, which are thereby de-energized and at ground potential for safety.

[0069] In the event that an obstacle, for example a person or an electrically conductive object, enters or is introduced under the electrical bus 1 from the side visible in [Fig. 1], thus entering the predetermined area including the live terminals, this obstacle interrupts the path of the light beam F9. The drawing D15 is then modified, and the secondary pattern M' 15 extracted from this drawing D15 is different from the primary pattern M15 that was transmitted to the comparator 19. Since the primary and secondary patterns are different, condition |3) is not satisfied.In this case, the S19 signal activates the on-board control unit 13, which in turn controls the control unit 27 to open the power-on switch 25 and ground the negative fixed terminals 31 and positive fixed terminals 33 by closing the grounding switches 28. This cuts off the power supply to the negative fixed terminals 31 and positive fixed terminals 33 of the static charging system, which are thus de-energized and at ground potential. The risk of electrocution from or via the obstacle is therefore eliminated.

[0070] At21 is noted as the longest processing time, including degraded modes between a loss of signal S19 and the grounding of the negative fixed terminals 31 and positive fixed terminals 33.

[0071] Vo denotes a maximum speed of movement of an obstacle or a human limb towards the predetermined zone mentioned above. This speed Vo can be normalized and, for example, equal to 2 m / s according to ISO 13855.

[0072] Advantageously, the distance dl is chosen to be strictly greater than the distance traveled by an obstacle moving at maximum speed Vo during the time interval At21. We have the following relationship:

[0073] dl > Vo x At21 (equation 1)

[0074] The invention is not limited to the case of a vehicle travelling on the right side of the road in continental Europe and equipped with the detection device on its left side. It also relates to the case of a vehicle travelling on the left side of the road and equipped with a detection device as described above on its right side.

[0075] The invention also relates to a vehicle traveling on either side of the roadway equipped with a detection device as described above on its side adjacent to a curb when the vehicle is stopped on the line. The invention also relates to a vehicle equipped with a detection device as described above on its front and / or rear.

[0076] Alternatively, the SI 1 signal can also be a signal other than video, for example a laser beam deflected to describe a pattern representative of the Ml5 code.

[0077] The embodiment and variants mentioned above can be combined with each other, insofar as this is technically possible.

Claims

Demands

1. Electric vehicle (1), configured to be recharged by means of a static charging system (2) and including an on-board detection system (5), the detection system (5) being configured to control the interruption of the electrical power supply and the grounding of the static charging system (2) in the event of detection of an object in a predetermined area, characterized in that the on-board detection system (5) comprises: - a time-varying primary pattern generator (15), - a light beam emitter (9) dependent on a primary pattern, generated by the primary pattern generator, - a light beam detector (11), - a pattern analyzer (17), configured to extract a secondary pattern (M'15) from the light beam detected by the light beam detector, - a pattern comparator (19),configured to compare the primary pattern (M15) and the secondary pattern (M'15) and to verify that the primary pattern is time-varying, - an on-board control unit (13), configured to remove the grounding and control the power-up of the static charging system (2), if and only if the pattern comparator (19) detects that: a) the primary pattern (M15) is time-varying, and |3) the primary (M15) and secondary (M'15) patterns are equal for a predetermined minimum duration.

2. Electric vehicle according to claim 1, wherein the primary pattern generator (15), pattern analyzer (17) and pattern comparator (19) belong to the same electronic control set (7), in particular the same electronic board or the same programmable electronic controller.

3. Electric vehicle according to any one of the preceding claims, wherein the emitter (9) is a light beam projector and the light beam detector (11) is a camera.

4. Electric vehicle according to any one of the preceding claims, wherein a minimum distance (dl) between the charging system (2) and a design (D15) formed on the ground by the light beam (F9) is greater than the product between, on the one hand, a deactivation time (At21) of the static charging system and, on the other hand, a predetermined speed of movement (Vo).

5. Electric vehicle according to any one of the preceding claims, wherein the primary motif (Ml5) varies with a variation frequency (fl5) between 1Hz and 20Hz, preferably on the order of 10Hz.

6. Electric vehicle according to any one of the preceding claims, wherein the predetermined minimum duration is between 85% and 95% of a pattern variation period, preferably equal to about 90% of the pattern variation period.

7. A method of recharging an electric vehicle (1) on a static charging system (2) according to any one of the preceding claims, characterized in that it comprises at least the following steps, consisting of: a. activate the primary pattern generator (15) (M15); b. transmit the primary pattern (Ml5) to the pattern comparator (19); c. emit, by means of the emitter (9), the light beam (F9) depending on the primary pattern (Ml5) generated by the pattern generator (15); d. acquire an image of a drawing (DI5) formed by the light beam (F9), by means of the light beam detector (11); e. extract a secondary pattern (M' 15) from a signal (SI 1) representative of the image acquired in step d), using the pattern analyzer (17); f. transmit the secondary pattern (M' 15) to the pattern comparator (19); g. compare the primary (M15) and secondary (M'15) patterns and verify that the primary pattern is variable over time using the pattern comparator (19); h. Disconnect the grounding and energize the static charging system (2), using the device of embedded control (13), if and only if step g) reveals that: a) the primary pattern (M15) is time-varying, and |3) the primary (M15) and secondary (M'15) patterns are equal for a predetermined minimum duration.

8. Method according to the preceding claim, wherein, in step c), the light beam (F9) is projected onto the ground, along the electric vehicle (1), between a publicly accessible area (R) and the static charging system (2).

9. Method according to any one of claims 7 or 8, wherein the primary pattern (M15) and the secondary pattern (M'15) are each a time-varying numeric code.

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