Patent Application
20200333148
Aspects of the disclosure generally relate to long-range navigation planning and charging strategy for electric vehicles.
Electric vehicles are becoming more and more popular. With the increased availability of charging stations, drivers are willing to take their vehicles on longer routes, recharging the vehicle batteries along the route. However, more optimal charging strategies may be appreciated by drivers.
An electrified vehicle may include a vehicle battery, and a processor configured to receive map data and generate a route based on the map data, and in response to a required vehicle energy needed to complete the route exceeding the current vehicle energy, modify the route to include at least one charging stop, wherein the at least one charge stop includes: a first number of shorter charging stops for recharging the battery at a first rate to a first state of charge less than a maximum state of charge, and a second number of longer charging stops for recharging the battery at a second rate to a second state of charge higher than the first state of charge, wherein the first rate is faster than the second rate and the first and second number of charging stops are selected to minimize combined charging time of the at least one charging stop.
A long-range navigation system for an electric vehicle may include a memory, and a processor configured to receive map data and generate a route based on the map data, the route associated with a calculated required energy needed to complete the route, and in response to the required energy exceeding a current vehicle energy, modify the route to include at least one charging stop to allow for recharging of a vehicle battery at a first rate, the first rate including a charge rate up to a threshold battery state of charge where the charge rate begins to decrease.
A method for recharging an electric vehicle along a route may receiving map data and generate a route based on the map data, and modifying, in response to a required energy required for completing the route exceeding a current energy, the route to include at least one charging stop along the route, the charging stop including at least one of a shorter charging stop for recharging of a vehicle battery at a first rate of charge less than a maximum state of charge and a second rate to a second state of charge higher than the first state of charge.
The embodiments of the present disclosure are pointed out with particularity in the appended claims. However, other features of the various embodiments will become more apparent and will be best understood by referring to the following detailed description in conjunction with the accompanying drawings in which:
As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.
Disclosed herein is a long-range navigation system for electric vehicles. Often, during long trips, the required energy needed to complete the trip may exceed the current vehicle energy. This may require an electric vehicle to recharge mid-trip. In some situations, charging time to fully recharge a battery of an electric vehicle may exceed four hours. This time may depend on the type of charger being used, as well as the battery state of charge (SOC), the battery size, speed of charge, etc. In general, the charging rate is faster when the state of charge is low. The charging rate may be slower when the state of charge is high. When charging a battery to full capacity, the battery may charge quickly at first, but the rate of charge may significantly decrease towards the end of charging when the state of charge is at a high percentage (e.g., 80-90%). A large amount of down-time during a trip may be inconvenient to the driver and passengers. Shorter charging times, even if requiring more stops, may be more tolerable and preferable to the driver. In some situations, multiple shorter charging stops may take less overall time out of the trip than a single longer charging stop.
The long-range navigation system disclosed herein may optimize charging stops by determining the fastest charging plan. In some examples, one longer charge stop may be more efficient, but in others, multiple shorter charge stops may save time overall. The navigation system takes into account the charging speeds, detour times required to reach a charging station, required energy for the trip, and current vehicle energy. The navigation system may develop a route plan that optimizes the charging time and overall trip time, while meeting all required energy needs.
The computing platform 104 may include one or more processors 106 configured to perform instructions, commands and other routines in support of the processes described herein. For instance, the computing platform 104 may be configured to execute instructions of vehicle applications to provide features such as navigation, accident reporting, satellite radio decoding, and hands-free calling. Such instructions and other data may be maintained in a non-volatile manner using a variety of types of computer-readable storage medium. The computer-readable medium (also referred to as a processor-readable medium or storage) includes any non-transitory medium (e.g., a tangible medium) that participates in providing instructions or other data that may be read by the processor 106 of the computing platform 104. Computer-executable instructions may be compiled or interpreted from computer programs created using a variety of programming languages and/or technologies, including, without limitation, and either alone or in combination, Java, C, C++, C#, Objective C, Fortran, Pascal, Java Script, Python, Perl, and PL/SQL.
The computing platform 104 may also receive input from human-machine interface (HMI) controls 136 configured to provide for occupant interaction with the vehicle 102. The computing platform 104 may also drive or otherwise communicate with one or more displays 138 configured to provide visual output to vehicle occupants by way of a video controller 140. In some cases, the display 138 may be configured to display state-of-charge (SOC) of the vehicle, including other information related to the stored energy of the vehicle such as trip range, battery range, etc. The display 138 may also be configured to display route information including a destination location, charge points, etc.
The computing platform 104 may be further configured to communicate with other components of the vehicle 102 via one or more in-vehicle networks 142. The in-vehicle networks 142 may include one or more of a vehicle controller area network (CAN), an Ethernet network, and a media oriented system transfer (MOST), as some examples. The in-vehicle networks 142 may allow the computing platform 104 to communicate with other vehicle 102 systems, such as a vehicle modem 144 (which may not be present in some configurations), a global positioning system (GPS) module 146 configured to provide current vehicle 102 location and heading information, and various vehicle ECUs (electronic control units) 148 configured to incorporate with the computing platform 104. As some non-limiting possibilities, the vehicle ECUs 148 may include a powertrain control module configured to provide control of engine operating components (e.g., idle control components, fuel delivery components, emissions control components, etc.) and monitoring of engine operating components (e.g., status of engine diagnostic codes); a body control module configured to manage various power control functions such as exterior lighting, interior lighting, keyless entry, remote start, and point of access status verification (e.g., closure status of the hood, doors and/or trunk of the vehicle 102); a radio transceiver module configured to communicate with key fobs or other local vehicle 102 devices; and a climate control management module configured to provide control and monitoring of heating and cooling system components (e.g., compressor clutch and blower fan control, temperature sensor information, etc.).
The vehicle 102 includes a battery 170. The battery 170 may include at least one high voltage (HV) battery such as a traction battery. The battery 170 may be used to power electric vehicles and provide high voltage direct current output. In addition to providing energy for propulsion, the traction battery may provide energy for other vehicle electrical systems.
The vehicle 102 may also include the long-range navigation system 172. This system may, in conjunction with the GPS module 146 and telematic systems, provide various routes to the vehicle. These routes may be based on a destination address as input by a user via the HMI controls 136. The route may include a start location and the destination location. The long-range navigation system 172 may receive the battery SOC from the battery 170, as well as fuel level from the ECUs 148. The long-range navigation system 172 may then determine whether the current vehicle energy is sufficient to complete the route. The current vehicle energy may include the distance the vehicle may travel on the current fuel energy, for vehicles having an internal combustion engine, and battery energy. In one example, the user may be prompted to select which type of energy to include, such as to only use battery power to determine the charge points or only use fuel energy. If the required energy for the route exceeds the current energy, the system 172 may identify various charge points along the route at which the vehicle battery 170 may be recharged. The location of the chart points and duration spent at each of the charge points may be optimized to achieve the shortest drive time. While the navigation system 172 is illustrated as being separate from the processor 106, the processor 106 may include or execute instructions from the navigation system 172.
Depending on the current battery SOC and fuel level indicating a distance to empty (DTE) of the vehicle, the vehicle 102 may not be able to travel the entire route without needing to recharge or refuel. If this is the case, the long-range navigation system 172 may determine certain charge points 210 where the vehicle 102 may stop along the route 200 to recharge, at least in part, the battery 170. The route 200 may include multiple charge points 210. The charge points 210 may be arranged at various points along the route 200. Although not shown, fuel stops could also be determined.
Each charge point 210 may be associated with a charging station 212. The charging stations 212 may be located within a maximum proximity (either predefined distance and/or time) to the charge point 210. In many instances, the charging stations 212 may be located at fuel stations at highway exits, etc. That is, the charging stations 212 may not be directly on the route 200, but instead, may require a detour from the route 200. The long-range navigation system 172 may determine a detour time associated with driving to the charging station 212. The detour time may depend on distance from the route 200, speed limits, traffic, etc. In the example shown in
charging time=charging segment+2(detour segment)=charging segment+2tx
In some examples, the route 200 may require one complete recharge of the battery 170. However, in the alternative to stopping once for a longer charge, the vehicle 102 may stop twice, but for shorter durations. The long-range navigation system 172 may take into consideration the time at each possible charge station and the charging speed at various states of charge. The charging rate of the two shorter segments may be much faster than the average charging rate of the longer segment.
The route 200 may be modified to include at least one charge stop 210. The charge stop 210 may include a first number of shorter charging stops for recharging the battery at a first rate (i.e., in the fast charging range 405) to a first state of charge less than a maximum state of charge or the threshold state of charge 415. The route 200 may also include a second number of longer charging stops for recharging the battery at a second rate (i.e., in the slow charging range 410) to a second state of charge higher than the first state of charge, wherein the first rate is faster than the second rate and the first and second number of charging stops are selected to minimize combined charging time of the at least one charging stop.
The route plan 502 may also include charging segments 512. The route plan 502 may include charging segments of varying durations. A first charging segment 512a may be considered a “fast charging time” where the vehicle battery 170 charges quickly, but likely does not complete charging of the battery 170. The first charging segment 512a may correspond to a first time ta. A second charging segment 512b may be similar. The second charging segment 512b may be associated with a second time tb. While the first and second charging segments 512a, 512b may differ in duration, each may be considered a “shorter” and “faster” charging segment when compared to a segment that fully charges the battery 170. While the first and second time segments 512a, 512b, may both be considered fast charging segments, the first time and second time may differ.
The long-range navigation system 172 may determine a total charge time for each of the route plans 502, 522. For example, the charging time for the first route plan 502 may include the charging segments 512 and detour segments 510. Thus, for the first route plan 502, the charging time may be t1=ta+tb.
For the second route plan 522, the charging time may be t2=tc. The navigation system 172 may then compare t1 and t2 to determine which of the two route plans have the shortest charging time.
Notably, each charging segment 512 may be associated with an energy. That energy may be the energy gained during the respective charging segments. For example, the first charging segment 512a may be associated with a first energy, the second charging segment 512b may be associated with a second energy, and so on. Each route plan may provide enough energy to complete the route 200. Thus, the energy of the routes may be fixed based on the required energy needed to complete the route. When comparing the routes to one another, the amount of energy acquired during the charging segments may be approximately the same sum total for each route. Thus, while the navigation system 172 may take into consideration the energy associated with each charging segment when selecting between the route plans 502, 522, the selection of the route is based on the charging time.
If t1>t2, and both of the route plans 502, 522 are presumed to acquire enough energy to complete the route, then the second route plan 522 may be selected by the navigation system 172. In this example, one longer charging segment may take less time overall than two shorter charging segments.
The long-range navigation system 172 may determine a total charge time for each of the third and fourth route plans 532, 542. For example, the charging time for the third route plan 532 may include the charging segments 512 and detour segments 510. Thus, for the third route plan 532, the charging time may be t3=td+te+tf. The charging time for the fourth route plan 542 may include the charging segments 512 and detour segments 510. Thus, for the fourth route plan 542, the charging time may be t4=tg+th. The navigation system 172 may then compare t3 and t4 to determine which of the two route plans have the shortest charging time.
For example, if t3<t4, then the third route plan 532 may be selected by the navigation system 172. In this example, three shorter charging segments 512 may take less time than two longer ones.
Generally, the navigation system 172 may optimize the route 200 when the distance to the destination is greater than the current range of the battery 170. In some examples, the distance to empty (DTE) may also be considered in determining whether the distance to the destination is greater than the current DTE. When more than a full charging energy is needed during the trip, two or more short but fast charging stops may require less time than one full charging time period.
The process 700 may begin at block 705 where the processor 106 may receive navigation data. The navigation data may include the vehicle's current location and the destination location. As explained, the current location may be received from the GPS module 146. The destination may be received from user input at the HMI controls 136 via the display 138, or other mechanisms of receiving destination locations.
At block 710, the processor 106 may generate a default route 200 based on the navigation data. This route 200 may be a regular route that does not take into account any energy requirements for completing the route 200. This route 200 may be a route that includes a fastest and/or shortest route based on the navigation preferences of the user.
At block 715, the processor 106 may calculate the required energy needed for the trip. This may take into consideration the power needed to drive along the route 200 and may take into consideration a driver's driving style, expected delays due to traffic or weather, topographical and incline data along the route, predicted cabin climate, etc.
Next, at block 720, the processor 106 may receive a current SOC of the battery 170 for BEVs. The processor 106 may also receive the current fuel level for PHEVs (plug-in hybrid electric vehicles). The current SOC may indicate the current EV range. The fuel level may indicate the current distance to empty (DTE). These may be combined to indicate the current vehicle energy.
At block 725, the processor 106 may determine whether the current vehicle energy is less than the required energy. In the example of a BEV, the current vehicle energy may be the EV range. In a PHEV, the current vehicle energy may also take into consideration the current distance to empty. If the required energy exceeds the current vehicle energy, the process 700 may proceed to block 730. If not, the process 700 may end.
At block 730, the processor 106 may calculate the energy gap between the required energy and current vehicle energy.
Following this, at block 735, the processor 106 may identify one or more charge points 210 along the route 200 as possible locations of recharge of the battery 170. The processor 106 may also search for possible charging stations 212 within a predefined radius (e.g., 5 miles) of the route 200.
At block 740, the processor 106 may generate a primary route plan. The primary route plan may include at least one charge point 210 where the vehicle 102 may recharge the battery 170 to a full capacity. This route plan may be similar to the second route plan 522, or the fourth route plan 542. While the examples show one and two charge points, more than this may be included, especially in the case of longer trips. The route plan may take into consideration the locations of the charge points 210, and the detours required to make it to the respective charging stations 212.
Next, at block 745, the processor 106 may determine whether a subsequent route plan is feasible. That is, could another variation of a route that includes one or more charging points 210 be generated and still achieve the required energy to complete the route. This subsequent route differs from the first route. The processor 106 may determine whether there are additional potential charge points 210 along the route that could offer alternative charging locations. If another subsequent route plan is possible due to additional charge points 210 along the route, the process 700 may proceed to block 750. If not, the process 700 may proceed to 755.
Further, at block 750, the processor 106 may generate a subsequent, or nth, route plan. The subsequent route plan(s) may focus on having charging segments that are considered the faster charging segments rather than just full capacity charging segments. As explained above, full capacity charging segments may include charging that charges the battery quickly, as well as segments that charge the battery slowly once a certain state of charge has been exceeded. For example, the battery may charge quickly from 20-80% SOC but slowly after 80%. In the example shown in
The subsequent route plan, similar to the primary route plan, may take into consideration the location of possible charge points 210, and the detours required to make it to the respective charging stations 212. In this example, the subsequent route plan may differ from the primary route plan. The subsequent route plan may be similar to the first and third route plans 502, 532. The process 700 may proceed to block 745 until no further route plans may be generated.
At block 755, the processor 106 may calculate the charging time for each of the first and subsequent route plans.
Then at block 760, the processor 106 may select the route plan with the shortest charging time. Additionally or alternatively, the user may be provided with the option to select from one or more route plans via the user interface and display 138. The user may have a preference as to which stops or just in general as to the charging strategy and may prefer to select which alternative route to travel.
At block 765, the processor 106 may update the default route 200 to include the one or more charging stations 212 as indicated by the selected route plan as waypoints.
Thus, the selected route plan is used to update the route 200 with various charging locations to allow the vehicle to recharge and optimize the charging time.
Computing devices, such as the processor, controller, remote servers, remote devices, etc., generally include computer-executable instructions, where the instructions may be executable by one or more computing devices such as those listed above. Computer-executable instructions may be compiled or interpreted from computer programs created using a variety of programming languages and/or technologies, including, without limitation, and either alone or in combination, Java™, C, C++, Visual Basic, Java Script, Perl, etc. In general, a processor (e.g., a microprocessor) receives instructions, e.g., from a memory, a computer-readable medium, etc., and executes these instructions, thereby performing one or more processes, including one or more of the processes described herein. Such instructions and other data may be stored and transmitted using a variety of computer-readable media.
While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention. Additionally, the features of various implementing embodiments may be combined to form further embodiments of the invention.
