FR2953625A3 - Navigation system for electric motor vehicle with traction battery, has monitoring system to check whether vehicle with remaining autonomy reaches two load points in calculated routes in continuous manner - Google Patents

Abstract

The system has a navigation module (200) whose calculation units (201) calculate routes from a current position of a vehicle towards a destination. An autonomy calculation module determines remaining autonomy of the vehicle in the calculated routes from a load state of the battery and calculated routes. The navigation module has a monitoring system (204) to check whether the vehicle with remaining autonomy reaches two load points in the calculated routes in a continuous manner. An independent claim is also included for a method for navigation of an electric motor vehicle.

Description

APPLICATION FOR PATENT B09 / 1716 / ODE / AR PJ-09-0046 YK / ST

Société par Actions Simplifiée known as: RENAULT s.a.s. Method and system for navigation of a vehicle including a warning of the user during the passage of the vehicle near the last reachable point of load. Invention of: BRAJON Thierry Method and system for navigation of a vehicle including a warning of the user during the passage of the vehicle near the last reachable point of load.

The present invention relates generally to the guidance of a motor vehicle and applies in particular to the guidance of any vehicle with limited autonomy.

The thermal vehicles use a tank type gauge to inform the user of the remaining battery life. The navigation systems installed in this type of vehicle offer a relevant route depending on the destination, whose travel time is minimum.

These solutions are not applicable to traction battery electric vehicles. As their autonomy is much less important, the navigation system must, on the one hand, integrate the notion of reachability, that is to say the possibility of reaching the destination and the charging points and, on the other hand, enable information to be obtained. uncertainties about the assessment of autonomy. Known in the state of the art, solutions for providing a user with information relating to the possibility of reaching a point of a path. The patent application FR 2915164 describes in this regard a warning device for the proximity of a toll zone. However this solution is limited to the warning and if necessary to a speed regulation. In any case, it is not a question of controlling the accessibility of charging points. In view of the foregoing, the object of the invention is to propose a navigation system which makes it possible to inform the user as to the possibility of reaching load points, while allowing an effective warning of the proximity of these charging points.

According to a first aspect, there is provided a navigation system for an electric motor vehicle equipped with a traction battery, comprising: a navigation module comprising means for calculating routes to a destination from the current position of the vehicle , storage means of the road network and charging points of the battery, - a battery calculation module able to determine from the state of charge of the battery and calculated routes, the remaining battery life of the vehicle in calculated routes. According to a general characteristic of this system, the navigation module further comprises a monitoring system configured to continuously check that the vehicle with its remaining range can reach at least two load points in the calculated routes. Thus, the user is notified as soon as only one point of load is reachable. In this sense, this warning corresponds to an indication of reachability of the destination. The warning is effective since it links the state of charge of the battery and the reachability of the last point of charge. The warning is also useful for the user since at the moment when it intervenes the battery is discharged, while the point of charge is near, and that point of charge is the last reachable. The navigation system, combining the continuous monitoring of the state of charge of the battery and reaching the last point of charge "without risk", allows a quieter user journey. According to one embodiment, the route calculation means comprise means for classifying the remaining route to be traveled according to accessibility levels. Estimating the consumption of a trip to a destination involves uncertainties. It is proposed autonomy information clear and simple to understand. This information is easily transposable on a map showing the route followed.

According to another embodiment, the autonomy calculation module comprises means for acquiring a raw autonomy information and a filter such that the filtered autonomy information is increasing as a function of time.

Thus the user is not likely to be surprised, a reassessment of autonomy systematically resulting in an increase in autonomy previously evaluated. According to a further embodiment, the route calculation means comprise means for evaluating the consumption and the duration of the routes to a destination, for classifying the itineraries according to their consumption and duration and means for proposing a first route, of which the journey time is minimum and a second economical route, whose consumption is minimum.

The user will be offered a more economical route with a lower impact on the environment. According to yet another embodiment, the means for proposing the first and second routes offer the second route if its travel time does not exceed a predetermined portion of the travel time of the first route. According to a second aspect, there is provided a method of navigation of an electric motor vehicle equipped with a battery, comprising: - a calculation of routes to a destination - a determination from the state of charge of the battery and routes, vehicle autonomy in the calculated routes According to a general characteristic of this process, it is implemented it is continuously monitored that the vehicle can with its remaining autonomy reach at least two load points in the routes calculated. According to one embodiment, the method further comprises a classification of the remaining route to be traveled according to accessibility levels.

According to a further embodiment, the method furthermore comprises: an acquisition of raw autonomy information; a filtering of this raw autonomy information so that the filtered raw autonomy is increasing as a function of time. According to another embodiment, the route calculation step includes an evaluation of the consumption and the duration of the itineraries towards a destination, a classification of these itineraries according to their consumption and their duration and a step of proposing a route. a first route, whose travel time is minimum and a second economical route, whose consumption is minimum. Subsequently, the user can select the route whose travel time is minimum or the route whose consumption is minimum. According to yet another embodiment, during the proposal step of the first and second routes, the second route is proposed if its travel time does not exceed a predetermined portion of the travel time of the first route. Other advantages and characteristics of the invention will become apparent upon studying the detailed description of embodiments and embodiments, taken by way of nonlimiting examples and illustrated by the appended drawings in which: FIG. 1 illustrates an embodiment of a navigation system; FIG. 2 illustrates an embodiment of the navigation element of the navigation system; - Figure 3 illustrates the different areas of accessibility; FIG. 4 illustrates the temporal evolution of the calculation of the autonomy as a function of the type of data considered. In Figure 1 are schematically illustrated the main elements of the navigation system and their exchanges. The navigation system includes a battery calculation module, a navigation module and a communication module with the outside. The autonomy calculation module is connected to the navigation module and to a power source, for example a battery. It can receive information on consumption on a journey to be traveled and the remaining energy translated into kilometers. This remaining energy corresponding to the remaining autonomy translated into kilometers is calculated according to the mode which is illustrated below in particular in Figure 4. To perform this calculation, it is taken into account to determine the remaining energy of multiple parameters among which: type of driving, consumption of auxiliaries (eg air conditioning). The communication module with the outside is connected to the navigation module and is linked to the outside. It can receive from the outside, availability information of the charging points.

I1 is then able from current vehicle position information to determine the availability of nearby charging points. It is also able to issue reservations at the request of the vehicle user on one of the neighboring charging points.

The navigation module is located at the interface of the two modules described above. It is able to inform the autonomy calculation module of the typology of the road and the traffic on the route, in return it receives from it a remaining energy translated into kilometers. Similarly, it is able to inform the communication module with the outside of the current position of the vehicle, which in turn informs him about the availability of nearby charging points. FIG. 2 illustrates in more detail the operation of the navigation module 200. This comprises means for determining the current position of the vehicle 202, the road network storage means and the load points 205 and a human interface. machine 203. The means for determining the current position of the vehicle can for example be made by a receiver type GPS (Global Positioning System). Road network storage facilities and charging points store road network mapping, roads and their characteristics, points of interest, towns and villages, and also charging points. These means can be realized by memories of the hard disk or flash type.

All the information stored for example in the storage means can be updated by updating means 206. These means may comprise communication means or means for reading a data medium. The navigation module 200 furthermore comprises means for calculating routes on the road network 201. Thus, starting from the current position of the vehicle, the cartography of the road network and the destination, the navigation module 200 is capable of determine a route from the point of departure to the point of destination. The destination point may be a destination entered by the user but also a point of charge. As an exemplary embodiment, the navigation module is able to determine the current relative position of the vehicle on the route followed. The route is communicated to the user of the vehicle by the man-machine interface 203. The man-machine interface is able in cooperation with the others of the route calculation module to display the route, the position of the vehicle on this one the positions of the point of departure and destination and the points of charge bordering the route. This interface can be realized by a display system. The human machine interface is also able to receive from the user a destination point. The human machine interface may, for example, include a keyboard on which the user enters the coordinates or address of the destination. The destination can be selected from a list previously stored in the human machine interface by the user. The human machine interface can also allow the user to make a reservation request for a charging point. This reservation request will be processed by the communication module with the outside. The navigation module is therefore able to guide the user of the vehicle from its current position to a destination point or a point of load. It has remaining energy information expressed in kilometers to a destination or charging points and information about the availability of nearby charging points. A guide mode capable of guiding the user through the man-machine interface can be activated for example in the case where the destination has been filled. The navigation module is also informed of nearby charging points and their availability. In the case where the guidance is activated, the route calculation means receive from the battery calculation module a remaining energy of the battery translated into kilometers. This information can be superimposed on the route as is illustrated in Figure 3 The navigation module further comprises a monitoring system 204. Thus, the navigation system can through the man machine interface, warn or alert the user. In the case where the guidance is active, the navigation system constantly checks that the user from his position on the route can go to the penultimate point of load attainable without risk. All that is required is for the monitoring system to be able to verify that around the chosen route there are two charging points in the distance corresponding to the remaining energy in kilometers from the current position. In this respect, the monitoring system cooperates with the route calculation means, the storage means for the charging points, the means for determining the current position and the autonomy calculation module. Also, when the penultimate point is no longer accessible, the user is notified by the man-machine interface of the navigation module: "there remains only one point of load reachable without risk". The navigation module can then offer to go there. If the user accepts, the navigation module guides it to the last reachable point of load and stores the final destination in memory to prevent the user from re-entering it. Otherwise, the current guidance continues. In the case where the navigation module finds no point of charge, it alerts the user: "there is no known charge point". In the case where the guidance is not active, the monitoring system checks at all times that there are at least two load points reachable according to the remaining energy. For this, the monitoring system can, for example, test the accessibility of each of the charging points among the closest. This research is established in cooperation with the storage means of the charging points, the means for determining the current position and the autonomy calculation module. The user is then notified or alerted according to the result of this search. If there is only one charging point left, the navigation module, via the HMI, warns the user of the vehicle that "there is only one point of load that can be reached safely". After the search, the navigation module can propose to the user to go to the point of load attainable without risk. If the user accepts, the navigation module guides it to the last point of load attainable.

If the monitoring system does not find a charging point, the navigation module alerts the user that "there is no known charging point". In other words, the monitoring system constantly monitors that at least two load points are reachable by the vehicle during its route if it is known, otherwise it monitors that two charging points are achievable. In Figure 3 is illustrated a representation of the remaining energy of the energy source as a function of the route on the route. In this representation, the chosen route is delimited into several zones. A first zone corresponds to an area of the route that can be reached safely with regard to autonomy. This zone is bounded by the minimum distance attainable. To determine this, an estimate of real-time consumption (shown below) is used. This area of the course is illustrated in Figure 3. This is the first on the left. It may, for example, be shown in green if necessary on the screen of the navigation system of the man-machine interface.

A second area indicating a portion of the route that is not reachable. It is bounded on the left by the maximum attainable distance. This zone corresponds to the zone on the right illustrated in FIG. 3. It may for example be shown in red if necessary on the screen of the navigation system.

Finally, a third, called intermediate, is inserted between the reachable area and the unreachable area. It is bounded by the minimum and maximum distances of route attainable on the route. It corresponds to an area of the route that is probably reachable by the vehicle. It is illustrated in Figure 3 in the middle of the two previous zones. For example, it may appear in orange on the navigation system screen of the man-machine interface. These three zones are represented proportionally to the kilometric distance they represent. They are determined according to the autonomy whose calculation is described below and illustrated in Figure 4. They are updated during the course of the route as well as in the case of a recharge to a point of charge, a change of destination, or a change of route. In other words, the computing means comprise means for classifying the remaining route according to accessibility levels. These indications can then be communicated by the human machine interface when the user enters a destination. Thus the user is informed of the possibility of reaching this destination. These indications can also be constantly superimposed by the route calculation means on the displayed route. The invention thus proposes with the introduction of an intermediate zone to overcome the uncertainty of the estimation of the remaining autonomy by a clear and precise information.

The charging points are stored in the road network storage means and load points of the navigation module. At a point of load many associated information can be stored among these: - its location (coordinates): coordinates for example GPS (according to an acronym Anglo-Saxon well known to those skilled in the art) are stored and associated with charging point - its availability in real time (via the communication module with the outside). This information is stored and updated regularly. It concerns the availability of different outlets of the charging point. The update of the availability can be done at the request of the user via the means of updating. This service requires a communication link with the outside in real time. This can be achieved by means of communication. In this respect, it is necessary to collect information on the availability of charging points in real time. This information is then aggregated by a service operator who broadcasts it (eg broadcasting by radio waves) or makes it available (eg request with a telephone network).

In Figure 4 are illustrated three curves and a line. The three curves represent the evolution of the estimation of autonomy. All three of them have as their asymptote the right which represents the real value of autonomy. The first curve, the information of gross autonomy, presents marked oscillations and a convergence towards the real value of the autonomy. Indeed, after a start of the vehicle, the autonomy information varies due to the lack of knowledge of certain parameters (mass of the vehicle, type of driver, ...). This information is refined after a certain number of kilometers.

The second curve, the filtered autonomy information (moderate filter) is in fact the result of a filtering of the gross autonomy curve. The first and second curves can not be used to calculate the remaining energy. Indeed, based on these curves, an unreachable load point could be evaluated as reachable to the user. The third curve has no oscillation, it is increasing and has as asymptote the real autonomy of the electric vehicle. This curve corresponds to the filtering of the raw autonomy information (strong filter). Using this curve, autonomy is underestimated but this is not detrimental. The user is not likely to be surprised, a reassessment of autonomy systematically resulting in an increase in autonomy previously evaluated. In other words, using the curve representing the filtered autonomy information (strong filter) of FIG. 4, the autonomy calculation module determines a minimum distance that can be reached on the route and / or to a point charge. The route calculation means on the road network are then able to determine a maximum attainable distance. For example, they multiply the minimum distance by a coefficient greater than 1 (and preferentially less than 1.25). The means for calculating at least one route can then superimpose on the route this reachable distance information. This information is then displayed as illustrated in Figure 3 by the man-machine interface. In the case of a conventional navigation, for example for a thermal vehicle, the criteria for choosing the route displayed to the user is, in general, the fastest. After entering the destination, the calculation means are able to determine several routes to get there from the current position of the vehicle. The different routes are then classified and the fastest is offered to the user of the vehicle. The classification can be carried out on the basis of an approximation of the journey time based on the data of the storage means of the road network (type of road, traffic, etc.). In the case of a navigation of another type, for example for an electric vehicle, the means for calculating routes on the road network can also provide a route whose consumption is minimum. For this, after choosing the fastest route to display to the user, all routes are classified according to the energy consumed. The classification can be made in the calculation means, based on an approximation according to the type of roads and the traffic stored in the storage means, an important accuracy is not necessary. The least-consuming route may be offered only if the total time of the least-consuming route does not exceed a predetermined portion of the time of the fastest route. Advantageously, this portion can be set at 40%. In this case, the user can then choose one of the two itineraries at his convenience, the default route being the fastest. In the case where there is only one route to a destination, this route is proposed for example as the fastest route. Similarly, if the fastest route is also the most economical then it will be proposed for example as the fastest route. Finally, to facilitate the choice of the user, the estimation of time and consumption for each of the two proposals will be displayed by the man-machine interface. Information such as the energy gain of the least-efficient versus faster route can also be displayed to the user. In conclusion, the proposed solution allows for reliable monitoring and effective warning, clear and accurate display of achievable areas. Thus, the course of the user is quieter, he does not have to worry about the problems of autonomy: "a guardian angel" watches constantly.

Claims (10)

REVENDICATIONS1. A navigation system for an electric motor vehicle with a traction battery, comprising: - a navigation module (200) comprising means for calculating routes (201) to a destination from the current position of the vehicle, means storage (205) of the road network and battery charging points, - a battery calculation module (100) capable of determining from the state of charge of the battery and calculated routes, the autonomy remaining vehicle in the calculated routes, characterized in that the navigation module (200) further comprises a monitoring system (204) configured to continuously check that the vehicle can with its remaining autonomy reach at least two load points in calculated routes. 2. Navigation system according to claim 1, wherein the route calculation means (201) comprises means for classifying the remaining route to be traveled according to accessibility levels. 3. System according to one of claims 1 and 2 wherein the autonomy calculation module (100) comprises a means for acquiring a raw autonomy information and a filter such as raw autonomy information. filtered is increasing with time. 4. System according to any one of the preceding claims, wherein the route calculation means (201) comprise means for evaluating the consumption and the duration of the routes to a destination, to classify the routes according to their consumption and their duration. and means for proposing a first route, whose travel time is minimum and a second economical route, whose consumption is minimum. 5. System according to claim 4, wherein the means for proposing the first and second routes offer the second route if its travel time does not exceed a predetermined portion of the travel time of the first route. 6. A method of navigation of an electric motor vehicle with a battery, comprising: - a calculation of routes to a destination - a determination from the state of charge of the battery and routes, the autonomy of the vehicle in the calculated routes characterized in that it is continuously monitored that the vehicle can with its remaining autonomy reach at least two load points in the calculated routes. 7. Navigation method according to claim 6, further comprising a classification of the remaining route to be traveled according to levels of accessibility. 8. Method according to one of claims 6 and 7 comprising: - an acquisition of raw autonomy information - a filtering of this raw autonomy information so that the filtered raw autonomy is increasing as a function of time . 9. Method according to one of the claims, the step of calculating itineraries comprises a consumption and the duration of the itineraries towards consumption and their itinerary duration, including the economical travel time, of which the 7 and 8, in which evaluation of the destination, a ranking of these routes according to them and a proposition of a first course is minimum and a second consumption is minimum. 10. The method of claim 9 wherein, during the proposal step of the first and second routes, the second route is proposed if its travel time does not exceed a predetermined portion of the travel time of the first route.