Temperature control of electric vehicle components while parking

Abstract

The present disclosure provides temperature control of electric vehicle components while parked. An electrically powered vehicle includes a power source, such as a battery or a DC power converter, that may require cooling during the time when the vehicle is parked. A heat transfer unit is coupled to the power source. A covering sensor configured to detect a covering provided on the electric vehicle that obstructs the heat transfer unit when parked; and a controller. When the covering is detected, the controller is configured to (A) determine a power supply temperature of the power supply, (B) compare the determined power supply temperature to a predetermined temperature threshold to detect an adverse condition, and (C) transmit a suggestion signal to a user that the covering should be removed when the adverse condition is detected.

Description

[0001] Cross - reference to related applications

[0002] Not applicable.

[0003] Statement regarding federally sponsored research

[0004] Not applicable. Technical field

[0005] The present invention generally relates to electrified vehicles and, more particularly, to a cooling / ventilation system that can be operated during vehicle parking to cool a battery and / or power supply electronics. Background art

[0006] Electrified vehicles or EVs (e.g., battery - electric vehicles and hybrid - electric vehicles) typically include a high - voltage battery pack that supplies power to one or more traction motors. Even when parked, the battery or battery pack may experience high temperatures, which may accumulate during driving or may occur due to power consumption by auxiliary systems that become active during parking. When recharging the battery pack, heat may also accumulate due to current flow.

[0007] An EV may also include a power converter or inverter that converts the high DC voltage (e.g., 800V) of the battery pack to a lower DC or AC voltage (e.g., 12V DC or 120V AC) for use when the vehicle is driven or parked. The power converter or inverter can also be used to generate an auxiliary power output for powering electrical accessories during the parked state of the vehicle, which may also result in heat generation within the power source (e.g., battery, converter, or inverter). Thus, cooling may be required when the EV is parked.

[0008] To cool the power source, an EV may utilize a fan, radiator, thermoelectric device, or other equipment to maintain the temperature within a desired range. The heat removed from the battery or electronics must be dissipated to the outside of the vehicle. Therefore, an air flow between the vehicle and the external environment must generally be maintained.

[0009] When the external temperature has risen (e.g., due to bright sunlight), the need for cooling may be greatest. Under these conditions, the likelihood that a user may wish to place a cover over the vehicle to protect it from bright sunlight and isolate the EV from the warm external environment may also increase. The protective cover may also be set on the vehicle for long periods of time and under variable weather conditions. Such a cover can be waterproof and breathable (i.e., capable of releasing water vapor). However, the application of such a cover may interfere with the air flow required to cool the EV when parked, especially since the cover may block the ends of the air flow channels or ducts through which air leaves the vehicle body. Summary of the invention

[0010] In one aspect of the present invention, an electric vehicle includes: a power source; a heat transfer unit coupled to the power source; a cover sensor configured to detect, when parked, a cover disposed on the electric vehicle that obstructs the heat transfer unit; and a controller. When the cover is detected, the controller is configured to (A) determine a power source temperature of the power source, (B) compare the determined power source temperature with a predetermined temperature threshold to detect an adverse condition, and (C) when the adverse condition is detected, transmit a recommendation signal to the user that the cover should be removed. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 is a perspective view of a vehicle cover.

[0012] Figure 2 is a perspective view of the vehicle.

[0013] Figure 3 is a perspective view of a vehicle cover disposed on the vehicle to reduce solar exposure.

[0014] Figure 4 is a partial cross-sectional view at a front grille of the vehicle where the cover obstructs the airflow of the heat transfer unit.

[0015] Figure 5 is a side view of an electrified vehicle having a cooling system for cooling a battery pack and a DC-DC converter.

[0016] Figure 6 is Figure 5 a schematic diagram of a part of the cooling system of

[0017] Figure 7 is a graph showing the motor current of a blower motor changing under a varying load due to obstructed airflow.

[0018] Figure 8 is a block diagram showing a vehicle according to an embodiment of the present invention.

[0019] Figure 9 is a flowchart showing an embodiment of the method of the present invention. DETAILED DESCRIPTION

[0020] Electrified vehicles typically utilize a blower fan, a radiator, and other heat transfer (e.g., cooling) mechanisms to maintain an optimal battery temperature and an optimal power converter temperature when the vehicle is turned off and parked. This can include the time for charging the battery pack and / or the time for the power converter or inverter to operate to support the assemblers at a job site.

[0021] Vehicle users sometimes desire to place covers on their vehicles to protect the vehicles from the elements, e.g., for sun protection during off - roading and camping. Such placement of the cover may impede battery cooling due to insufficient airflow, resulting in an undesired increase in the temperature of the power source. To avoid these high temperatures, the present invention can use various sensors (e.g., fan sensors that may already exist for performing diagnostics including fan current or fan speed) to determine if the airflow openings (e.g., radiator openings, duct openings, or grille openings) are unobstructed before activating the associated cooling components, if the external conditions and / or the power source temperature require such an action.

[0022] In some embodiments, when the vehicle is turned off with the key (i.e., the engine is off), a determination can be made as to whether the currently measured power source (battery or power converter / inverter) temperature or current or the predicted (future) ambient temperature or sunlight exposure is likely to cause the power source temperature to exceed a calibration threshold in the case where an automotive cover is to be used. For example, this determination can be based on a model using empirical data on how battery temperature changes with key - off under certain environmental conditions (e.g., based on geographical location and weather forecast).

[0023] The vehicle can also map out in advance the locations where a cover is most likely to be installed based on expected sunlight exposure and / or ambient temperature. If the current vehicle location corresponds to one of these locations (as determined by a location service such as GPS), the user can be advised not to install the automotive cover (or at least not to use a cover that does not provide a certain level of breathability or that does not avoid covering certain areas of the vehicle).

[0024] An external sensor suite that may include external or internal cameras can be used to detect the presence of a cover placed on the vehicle. For example, when all cameras show a continuous monochromatic area outside the vehicle and when all internal cameras show that all windows are blocked, it is likely that an automotive cover is installed. Alternatively, user input (e.g., a spoken command or a button press) can be used to determine if the automotive cover is installed. When necessary, the user can be notified via the infotainment unit or other human - machine interface via an audible tone or announcement and / or a text message. The user can be notified using wireless communication, such as a message sent from the vehicle to a mobile smartphone or other device running a vehicle management app (e.g., Ford app).

[0025] When the vehicle cover is installed but there is no response to the suggestion to remove it, the present invention may further include taking mitigation actions. The mitigation actions may include seeking help from nearby people via an audible request, performing preventive cooling of the EV battery pack, running the blower fan in reverse to attempt to blow away an obstacle, or autonomously moving the vehicle to a more favorable location (e.g., a shaded area). The mitigation actions may include changing the operation of the power supply to reduce heat generation. For example, the DC power converter may be switched to a lower output or completely deactivated (e.g., after notifying the user).

[0026] Figure 1 A vehicle cover 10 is shown, which may include a synthetic or natural fabric. The cover 10 may be waterproof and adapted to reflect solar heat and radiation. The fabric may be "breathable" to allow evaporation of moisture beneath the cover 10. However, such known fabrics tend to limit the airflow through the cover 10 to less than that required for the normal operation of the battery cooling system, especially at high ambient temperatures.

[0027] Figure 2 An electrified vehicle (EV) 11 is shown. Figure 3 A cover 10 disposed on the vehicle 11 is shown, which is used to provide a barrier between the outer surface of the vehicle 11 and the external environment, thereby protecting the vehicle 11 from precipitation and / or sunlight. However, the presence of the cover 10 may impede the airflow involved in the thermal management (e.g., cooling) of electrical components that may be required even when the vehicle is parked. As Figure 4 shown, an air flow outlet 12 communicated via the front grille of the vehicle 11 may be effectively blocked by the cover 10, which may extend downward to fully accommodate the grille area.

[0028] Figure 5 The vehicle 11 is shown in more detail. The air flow outlet 12 is connected to a heat transfer (e.g., cooling) unit 13 via a duct 14. The cooling unit 13 is arranged to cool the battery pack 15 and the DC-DC converter 16. Any type of heat transfer unit or HVAC component suitable for use in a vehicle may be utilized, such as an evaporative air cooler (eAC), a heat pump, a heat exchanger, and a coolant-based unit.

[0029] In Figure 6An embodiment of the cooling unit 13 is shown in more detail and includes a blower fan 20 for driving air flow through the duct 14. The blower fan 20 is rotated by an electric motor 21 under the control of a motor drive circuit 22. A radiator 23 is disposed in the duct 14 between the outlet 12 and the inlet 17. The compressor / evaporator 24 is in thermal communication with a power source (e.g., a battery or a power converter) to transfer heat from the power source to a refrigerant, and the refrigerant carries the heat to the radiator 23 via the duct 25. The air flow driven by the blower fan 20 then transfers the heat to the external environment. When the air flow in the duct 14 is blocked by a cover that obstructs the outlet 12 or the inlet 17, the load on the electric motor 21 increases. As Figure 7 shown, when the load increases, the current drawn by the motor 21 also increases along the curve 27. By comparing the instantaneous current along the curve 27 with a motor current threshold 28, the presence of the cover can be inferred when the air flow blockage becomes sufficient to increase the motor load to a point where the motor current is higher than the threshold 28.

[0030] Figure 8 The vehicle 11 is shown in more detail. The controller 30 may include one or more programmable general electronic modules, such as a body control module (BCM). The controller 30 is coupled to a battery monitor 31 and a climate monitor 32 for collecting information used in the present invention. For example, the battery monitor 31 may provide the controller 30 with an instantaneous measured temperature of the battery pack. The climate monitor 32 may include sensors for determining the external ambient temperature and / or the sunlight conditions. The controller 30 is further coupled to the DC–DC converter 16 in order to obtain instantaneous temperature information detected at the converter 16. The controller 30 is further coupled to a sensor suite 33, which may include external and / or internal cameras and other sensors that can be configured to detect the presence of a cover disposed on the vehicle 11.

[0031] The controller 30 is coupled to a GPS receiver 34 having an antenna 35 to obtain geographical coordinates, which are used in combination with determining weather forecasts or other climate-related information to predict, for example, the future temperature of the power source. The controller 30 is further coupled to a wireless link 36 having an antenna 37 in order to collect external data, including weather forecasts, future temperatures, or expected sunlight based on the geographical coordinates obtained from the GPS 34.

[0032] The controller 30 is further coupled to the fan circuit 22 to receive a measured motor current from a motor current sensor in the fan circuit 22. The controller 30 compares the measured motor current to a motor current threshold to detect when the airflow resistance encountered by the blower fan is at a level indicating that the airflow is blocked by a covering. The controller 30 may include data of a model 38 that utilizes various remotely and locally determined variables to predict the future temperature of the power source and identify adverse temperature conditions that may be caused by the presence of a vehicle covering.

[0033] The controller 30 is coupled to a human-machine interface HMI 40, which may be configured to obtain an input from a user indicating the application of a covering (e.g., via a button press or a spoken command received). The HMI 40 may further include a display screen and a speaker for emitting a recommendation signal to the user when a covering should be removed and / or a covering should not be installed due to detected existing or anticipated adverse conditions of the power source temperature.

[0034] The DC–DC converter 16 and the battery system may respond to the controller 30 to change their operations to reduce heat generation, as another mitigation action. The controller 30 may further include an autonomous powertrain controller function for removing the vehicle 11, as a mitigation action. Additionally, the circuit 22 may respond to the controller 34 to operate the fan in a manner that relocates the covering or otherwise clears an obstacle to the airflow (e.g., by temporarily reversing the fan operation direction).

[0035] Figure 9 An example method of the present invention is shown, where in step 41, the current and / or predicted future temperature of the power system is determined. In step 42, an inspection is performed to determine whether the measured / predicted temperature is within a temperature range indicating adverse conditions (e.g., when the temperature exceeds a threshold thereby indicating a need for cooling). If so, then in step 43, the user is advised not to use the covering by emitting a recommendation signal. After the advice or when the power source temperature is determined not to exceed the temperature threshold, then in step 44, an inspection is performed to determine whether the covering has actually been placed. If not, the method may end at step 45.

[0036] In some embodiments, step 44 may be performed periodically to detect a later application of the covering. Whenever step 44 determines that the covering has been set on the vehicle, an inspection is performed in step 46 to determine whether an excessive temperature has occurred in the power source (i.e., an adverse condition). If not, step 46 may be repeated periodically to recheck the power source temperature. If the power source temperature exceeds a predetermined threshold in step 46, a recommendation message may be emitted to the user in step 47, where the recommendation message may advise that the covering should be removed or notify the user that the operation of the power source may be reduced to limit the amount of heat generated.

[0037] In step 48, a check is performed to determine whether the covering has been removed within a predetermined amount of time in accordance with the advisement message. If not, the method is completed at step 49. Otherwise, a mitigation action may be activated at step 50. As described above, the mitigation action may include repositioning the vehicle, initiating a local distress call via an audible signal to seek a nearby person to remove the covering, operating the fan in reverse, or cooling the power supply by changing its operation or finding an alternative cooling means.

[0038] In one aspect of the present invention, the step of detecting the presence of the covering includes capturing an image from at least one camera in response to the placement of the covering on the electric vehicle.

[0039] In one aspect of the present invention, the step of detecting the presence of the covering includes receiving a manual indication of the installation of the covering from the user via a user input element.

[0040] In one aspect of the present invention, the advisement signal includes at least one of a wireless message delivered to the user's mobile device and an audible communication emitted by the electric vehicle.

[0041] In one aspect of the present invention, the method includes the steps of: detecting a lack of response from the user to the advisement signal; and initiating a mitigation action to reduce the adverse condition, where the mitigation action is one of the following: (i) changing the operation of the power supply to reduce heat generation, (ii) autonomously moving the electric vehicle to a location less likely to experience the adverse condition, or (iii) operating a fan within the heat transfer unit in a manner to reposition the covering.

[0042] In one aspect of the present invention, the power supply temperature is the predicted future temperature of the power supply during the current parking event of the electric vehicle.

Claims

1. An electric vehicle, comprising: A power source; A heat transfer unit coupled to the power source; A cover sensor configured to detect, when parked, a cover disposed on the electric vehicle that obstructs the heat transfer unit; And A controller, wherein when the cover is detected, the controller is configured to (A) determine a power source temperature of the power source, (B) compare the determined power source temperature with a predetermined temperature threshold to detect an adverse condition, and (C) when the adverse condition is detected, transmit a recommendation signal to the user that the cover should be removed.

2. The electric vehicle according to claim 1, wherein the heat transfer unit includes a blower coupled to an air duct that directs an air flow outward from an outer surface of the electric vehicle covered by the cover.

3. The electric vehicle according to claim 2, wherein the blower includes a fan, a motor coupled to the fan, and a motor drive circuit coupled to the motor, wherein the cover sensor includes a motor current sensor, and wherein the cover is detected when a current measured by the motor current sensor is greater than a predetermined current threshold.

4. The electric vehicle according to claim 2, wherein the heat transfer unit further includes a heat exchanger for actively changing a temperature of the air flow, and wherein the heat transfer unit includes at least one of an evaporative air cooler, a heat pump, or a coolant flow-based unit.

5. The electric vehicle according to claim 1, wherein the cover sensor includes at least one camera responsive to placement of the cover on the electric vehicle.

6. The electric vehicle according to claim 1, wherein the cover sensor includes a user input element configured for a manual indication by the user of installation of the cover.

7. The electric vehicle according to claim 1, wherein the recommendation signal includes a wireless message delivered to the user's mobile device.

8. The electric vehicle according to claim 1, wherein the recommendation signal includes an audible communication emitted by the electric vehicle.

9. The electric vehicle according to claim 1, wherein the controller is further configured to (D) detect a lack of response from the user to the recommendation signal, and (E) initiate a mitigation action to reduce the adverse condition.

10. The electric vehicle according to claim 9, wherein the mitigation action is at least one of the following: (i) changing an operation of the power source to reduce heat generation, (ii) autonomously moving the electric vehicle to a location less likely to experience the adverse condition, or (iii) operating a fan within the heat transfer unit in a manner to reposition the cover.

11. The electric vehicle according to claim 1, wherein the power source temperature determined by the controller is an instantaneous temperature of the power source.

12. The electric vehicle according to claim 1, wherein the power source temperature determined by the controller is a predicted future temperature of the power source during a current parking event of the electric vehicle.

13. The electric vehicle according to claim 1, wherein the power supply includes at least one of a battery pack, a voltage converter, and a voltage inverter.

14. A method for controlling the temperature of a power supply in an electric vehicle during parking: wherein the electric vehicle includes a heat transfer unit coupled to the power supply; and a cover sensor configured to detect a cover disposed on the electric vehicle that obstructs the heat transfer unit, the method comprising the steps of: Determining the power supply temperature of the power supply; Comparing the determined power supply temperature with a predetermined temperature threshold to detect an adverse condition; Detecting the presence of the cover that obstructs the heat transfer unit; And When the adverse condition is detected, transmitting a recommended signal to the user that the cover should be removed.

15. The method according to claim 14, wherein the heat transfer unit includes A fan; a motor coupled to the fan; and a motor drive circuit coupled to the motor, wherein the cover sensor includes a motor current sensor, and wherein the step of detecting the presence of the cover includes detecting when the current measured by the motor current sensor is greater than a predetermined current threshold.

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