Method for estimating the autonomy of an electric or hybrid vehicle
A method for estimating a range of an electric or hybrid vehicle over a predetermined trip includes estimating energy available in a traction battery of the vehicle as a function of a temperature of the battery and calculating a value representative of a trend of the temperature of the battery during the trip. The value is used to estimate the energy available.
1. A method for estimating a range of an electric or hybrid vehicle equipped with a navigation system over a trip, the method comprising:
receiving prior to beginning the trip, using circuitry and based on operation of the navigation system, data corresponding to the trip input by a user of the vehicle;
estimating prior to beginning the trip, using the circuitry, energy available in a traction battery of the vehicle as a function of a temperature of said battery for the trip;
calculating prior to beginning the trip, using the circuitry, a value representative of a trend of the temperature of the battery during the trip, said value being used to estimate the energy available;
estimating prior to beginning the trip, using the circuitry, the range of the vehicle based on the estimated energy available; and
controlling output of the estimated range of the vehicle, using the circuitry, to a dashboard of the vehicle prior to beginning the trip,
wherein the calculating the representative value includes:
subdividing the trip into p sections, where p is a strictly positive integer number; and
estimating the temperature of the battery at an end of each of the p sections.
2. The method as claimed in claim 1 , wherein the calculating the representative value further includes:
the representative value being equal to a minimum value out of the p temperature values of the battery at the end of each of the p sections, or
the representative value being equal to an average value of the p temperature values of the battery at the end of each of the p sections.
3. The method as claimed in claim 1 , wherein the subdividing of the trip into p sections includes:
inputting a destination of the trip by the user of the vehicle via an interface of the navigation system, which is connected to the vehicle; and
pre-subdividing of the trip by the navigation system into q sections, where q is a strictly positive integer number less than or equal to p, such that an average speed of the vehicle estimated by the navigation system over each of the q sections varies from one section to the next over the trip.
4. The method as claimed in claim 3 , wherein the subdividing of the trip into p sections further includes, when some sections out of the q sections have an estimated travel time greater than a predetermined threshold, re-subdividing of said sections for which the estimated travel time is greater than the predetermined threshold, such that the travel time of each of the p sections thus obtained is less than or equal to the threshold.
5. The method as claimed in claim 3 , wherein, for i an integer varying from 1 to p, the navigation system supplies:
the average speed over the i th section as a function of traffic conditions over said section; and
an average outdoor temperature predicted over the i th section.
6. The method as claimed in claim 1 , wherein the estimating the temperature of the battery at the end of each of the p sections includes, for i an integer varying from 1 to p:
estimating, as a function of an average speed estimated over the i th section, of an average current passing through the battery during the i th section;
estimating a temperature, at the start of the i th section, of a heat transfer fluid making it possible to heat up or cool down the battery;
collecting an average outdoor temperature predicted over the i th section;
estimating the temperature of the battery at an instant when the vehicle reaches the end of the i th section, from:
the estimated temperature of the battery at the end of the (i−1) th section or the measured temperature of the battery if i=1, and/or;
the estimated average current passing through the battery during the i th section, and/or;
the average outdoor temperature predicted over the i th section, and/or;
the estimated temperature of the heat transfer fluid at the start of the i th section.
7. The method as claimed in claim 6 , wherein the estimating the temperature of the battery at the end of each of the p sections includes estimating, for i an integer varying from 1 to p, the temperature of the battery at the end of the i th section by the equation:
Tpack
(
ti
)
=
[
Tpack
(
ti
-
1
)
-
γ
·
(
Iaverage_i
)
2
+
δ
·
Text_i
+
θ
·
Tcooling_i
δ
+
θ
]
·
e
-
(
δ
+
θ
)
-
ti
+
γ
·
(
Iaverage_i
)
2
+
δ
·
Text_i
+
θ
·
Tcooling_i
δ
+
θ
in which γ, δ and θ are parameters corresponding to thermal characteristics of the battery,
Tpack(ti−1) is the estimated temperature of the battery at the end of the (i−1) th section,
Iaverage_i is the average current passing through the battery during the i th section,
Text_i is the average outdoor temperature predicted over the i th section, and
Tcooling_i is the temperature, at the start of the i th section, of the heat transfer fluid.
8. The method as claimed in claim 1 , wherein the range corresponds to a range margin beyond a destination associated with the trip.
9. The method as claimed in claim 1 , wherein the range corresponds to a total range of the vehicle prior to beginning the trip and/or a total range of the vehicle during the trip.
10. The method as claimed in claim 1 , wherein said calculating the value representative of the trend of the temperature of the battery during the trip is based on a function of temperature of a cooling system over time for the trip.
11. A computer, comprising hardware and software means configured to implement the method as claimed in claim 1 .
12. An electric or hybrid vehicle, comprising:
the computer as claimed in claim 11 ; and
the dashboard on which to display the estimated range.
13. A method for estimating a range of an electric or hybrid vehicle equipped with a navigation system over a trip, the method comprising:
receiving prior to beginning the trip, using circuitry and based on operation of the navigation system, data corresponding to the trip input by a user of the vehicle;
estimating prior to beginning the trip, using the circuitry, energy available in a traction battery of the vehicle as a function of a temperature of said battery for the trip;
calculating prior to beginning the trip, using the circuitry, a value representative of a trend of the temperature of the battery during the trip, said value being used to estimate the energy available;
estimating prior to beginning the trip, using the circuitry, the range of the vehicle based on the estimated energy available; and
controlling output of the estimated range of the vehicle, using the circuitry, to a dashboard of the vehicle prior to beginning the trip,
wherein the range corresponds to a range margin beyond a destination associated with the trip.
14. The method as claimed in claim 13 , wherein said calculating the value representative of the trend of the temperature of the battery during the trip is based on a function of temperature of a cooling system over time for the trip.
15. A computer, comprising hardware and software means configured to implement the method as claimed in claim 13 .
16. An electric or hybrid vehicle, comprising:
the computer as claimed in claim 15 ; and
the dashboard on which to display the estimated range.
17. A method for estimating a range of an electric or hybrid vehicle equipped with a navigation system over a trip, the method comprising:
receiving prior to beginning the trip, using circuitry and based on operation of the navigation system, data corresponding to the trip input by a user of the vehicle;
estimating prior to beginning the trip, using the circuitry, energy available in a traction battery of the vehicle as a function of a temperature of said battery for the trip;
calculating prior to beginning the trip, using the circuitry, a value representative of a trend of the temperature of the battery during the trip, said value being used to estimate the energy available;
estimating prior to beginning the trip, using the circuitry, the range of the vehicle based on the estimated energy available; and
controlling output of the estimated range of the vehicle, using the circuitry, to a dashboard of the vehicle prior to beginning the trip,
wherein the range corresponds to a total range of the vehicle prior to beginning the trip and/or a total range of the vehicle during the trip.
18. The method as claimed in claim 17 , wherein said calculating the value representative of the trend of the temperature of the battery during the trip is based on a function of temperature of a cooling system over time for the trip.
19. A computer, comprising hardware and software means configured to implement the method as claimed in claim 17 .
20. An electric or hybrid vehicle, comprising:
the computer as claimed in claim 19 ; and
the dashboard on which to display the estimated range.