electric vehicles

Abstract

This contributes to improving the accuracy of the predicted battery temperature adjustment time required to regulate the battery temperature so that it is within a suitable temperature range for charging upon arrival at the destination. [Solution] Based on the destination set by the navigation system and the current location, the system predicts the battery temperature adjustment time required for the battery temperature to reach a suitable temperature for charging by the air conditioning system when the destination is reached. The difference between the predicted battery temperature adjustment time and the actual time required for temperature adjustment by the air conditioning system is stored as the actual predicted time difference.

Description

Technical Field

[0001] The present disclosure relates to an electric vehicle, and more particularly to an electric vehicle in which a battery can be temperature-controlled by an air conditioner that air-conditions a passenger compartment.

Background Art

[0002] Conventionally, as this type of electric vehicle, when the battery can be charged after moving to the destination, there has been proposed a vehicle that controls the temperature of the battery so as to be within a temperature range suitable for charging (see, for example, Patent Document 1). In this electric vehicle, by setting the temperature of the battery to a temperature range suitable for charging when arriving at the destination, an increase in the charging time is suppressed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the above-described electric vehicle, it is necessary to predict the time required to temperature-control the battery (predicted battery temperature control time) in order to make the temperature of the battery within a temperature range suitable for charging when arriving at the destination. When the predicted battery temperature control time is shorter than the actual time required to actually make the temperature of the battery within a temperature range suitable for charging, it often becomes impossible to make the temperature of the battery within a temperature range suitable for charging. Conversely, when the predicted battery temperature control time is longer than the actual time, although it is possible to make the temperature of the battery within a temperature range suitable for charging, the battery is temperature-controlled using excessive energy. Therefore, it is necessary to improve the accuracy of the predicted battery temperature control time.

[0005] The electric vehicle of this disclosure primarily aims to improve the accuracy of the predicted battery temperature adjustment time required to adjust the battery temperature so that the battery temperature is within a suitable range for charging upon arrival at the destination. [Means for solving the problem]

[0006] The electric vehicle of this disclosure employs the following means to achieve the main objective described above.

[0007] The electric vehicle disclosed herein is An electric motor that inputs and outputs power for propulsion, A battery that exchanges power with the aforementioned electric motor, An air conditioning system that provides air conditioning for the crew compartment and also controls the temperature of the battery, Navigation system and, A temperature control device for controlling the temperature of the aforementioned battery, An electric vehicle equipped with, The temperature control device predicts the battery temperature adjustment time required for the battery temperature to reach a suitable temperature for charging by the air conditioning system when the destination is reached, based on the destination set by the navigation system and the current location, and stores the difference between the predicted battery temperature adjustment time and the actual time required for temperature adjustment by the air conditioning system as the actual predicted time difference. It is characterized by the following:

[0008] In the electric vehicle of this disclosure, the predicted battery temperature adjustment time required for the battery temperature to reach a suitable temperature for charging by the air conditioning system upon arrival at the destination is predicted based on the destination set by the navigation system and the current location. The difference between the predicted battery temperature adjustment time and the actual time required for temperature adjustment by the air conditioning system is then stored as the actual predicted time difference. By making predictions for the battery temperature adjustment time in such a way that the stored actual predicted time difference (the difference between the predicted battery temperature adjustment time and the actual time) is minimized, the accuracy of the predicted battery temperature adjustment time can be improved. In this way, storing the actual predicted time difference (the difference between the predicted battery temperature adjustment time and the actual time) contributes to improving the accuracy of the predicted battery temperature adjustment time.

[0009] In the electric vehicle of this disclosure, the temperature control device may calculate the predicted battery temperature control time each predetermined time elapsed since the start of temperature control by the air conditioning device, calculate the predicted time difference obtained by subtracting the currently calculated predicted battery temperature control time from the previously calculated predicted battery temperature control time and the predetermined time each predetermined time elapsed, and store the maximum value of the predicted time difference calculated each predetermined time elapsed as the actual predicted time difference. In this way, the maximum value of the predicted time difference calculated each predetermined time elapsed during the temperature control of the battery by the air conditioning device can be stored, and this maximum value of the predicted time difference can be used to improve the accuracy of the predicted battery temperature control time.

[0010] In the electric vehicle of this disclosure, the temperature control device may distinguish and store the difference in actual predicted time when the temperature of the battery is controlled by the air conditioning system while the passenger compartment is being air-conditioned by the air conditioning system, and the difference in actual predicted time when the temperature of the battery is controlled by the air conditioning system while the passenger compartment is not being air-conditioned by the air conditioning system. By distinguishing between the state in which the passenger compartment is being air-conditioned and the state in which the passenger compartment is not being air-conditioned, it is possible to improve the accuracy of the predicted battery temperature control time predicted in each state. [Brief explanation of the drawing]

[0011] [Figure 1] This is a schematic diagram showing the configuration of an electric vehicle 20 as one embodiment of the present disclosure. [Figure 2] This flowchart shows an example of the actual predicted difference time storage process performed by the electronic control unit 50. [Modes for carrying out the invention]

[0012] Next, embodiments for implementing this disclosure will be described. Figure 1 is a schematic diagram showing the configuration of an electric vehicle 20 as one embodiment of this disclosure. As shown in the figure, the electric vehicle 20 of the embodiment includes a motor 22, an inverter 24, a battery 30, a bidirectional charging device 32, an air conditioning device 36, a navigation device 80, and an electronic control unit 50.

[0013] The motor 22 is configured, for example, as a three-phase AC motor, and comprises a rotor in which permanent magnets are embedded in a rotor core, and a stator in which three-phase coils are wound around a stator core. The rotor of the motor 22 is connected to a drive shaft 26 which is connected to drive wheels 28a and 28b via a differential gear 27.

[0014] The inverter 24 is used to drive the motor 22. The inverter 24 is connected to the battery 30 via a power line and consists of a well-known inverter circuit having six transistors as switching elements and six diodes connected in parallel to each of the six transistors.

[0015] The battery 30 is configured as a lithium-ion secondary battery or a nickel-metal hydride secondary battery and is connected to the inverter 24 via a power line.

[0016] The bidirectional charging device 32 is connected to the power line between the battery 30 and the inverter 24, and is configured as a circuit that charges the battery 30 with power from an external power source or supplies power from the battery 30 to an external power supply. The bidirectional charging device 32 is equipped with a connector 34 for connecting to an external charging stand or an external power supply stand.

[0017] The air conditioning unit 36 ​​provides air conditioning to the crew compartment and also exchanges heat with the battery 30 by circulating a heat exchange medium through a circulation channel 37 to the battery 30, thereby heating or cooling the battery 30 to regulate its temperature.

[0018] The electronic control unit 50 is configured as a microcomputer having a CPU 51, a ROM 52, a RAM 53, a flash memory 54, input / output ports and communication ports (not shown). Signals from various sensors are input to the electronic control unit 50 via the input ports. Examples of the signals input to the electronic control unit 50 include the rotational position θ from the rotational position detection sensor 23 that detects the rotational position of the rotor of the motor 22, the battery voltage Vb from the voltage sensor 31a attached between the output terminals of the battery 30, the battery current Ib from the current sensor 31b attached to the power line, the battery temperature Tb from the temperature sensor 31c attached to the battery 30, and the like. Further, examples include the ignition signal from the ignition switch 60, the vehicle speed V from the vehicle speed sensor 61, the acceleration α from the acceleration sensor 62, the wheel speeds Vw1 to Vw4 of the respective wheels from the wheel speed sensors 63, and the like. Also, examples include the shift position signal SP from the shift position sensor 65 that detects the position of the shift lever 64, the accelerator opening Acc from the accelerator pedal position sensor 67 that detects the depression amount of the accelerator pedal 66, and the brake pedal position BP from the brake pedal position sensor 69 that detects the depression amount of the brake pedal 68. Furthermore, examples include the outside air temperature Tout from the outside air temperature sensor 73 and the on / off signal from an air conditioning switch (not shown) that instructs the on / off of the air conditioner 36.

[0019] Various control signals are output from the electronic control unit 50 via the output ports. Examples of the control signals output from the electronic control unit 50 include the display control signal to the display device 70, the communication control signal to the communication device 72, the air conditioning control signal and the temperature control signal to the air conditioner 36, and the like. The electronic control unit 50 calculates the state of charge SOC of the battery 30 based on the battery voltage Vb from the voltage sensor 31a and the battery current Ib from the current sensor 31b, and calculates the rotational speed Nm of the motor 22 based on the rotational position θ from the rotational position detection sensor 23.

[0020] The navigation device 80 includes a main body 82 with a built-in control unit, a GPS antenna 84 that receives information on the current location of the vehicle, and a display 86. The control unit of the main body 82 has a storage medium (such as a hard disk or SSD) in which map information and the like are stored, input / output ports, and communication ports. In the map information, service information (such as tourist information and parking lots) and road information for each driving section (such as between traffic lights and between intersections) are stored as a database. The road information includes distance information, width information, number of lanes information, regional information (urban areas and suburbs), type information (ordinary roads and highways), gradient information, legal speed, number of traffic lights, turning radius of each curve, and the like. The display 86 is configured as a touch panel type display that displays various information such as information on the current location of the vehicle and the planned driving route to the destination, and enables the user to input various instructions. When the destination is set by the user's operation on the display 86, the main body 82 of the navigation device 80 sets a planned driving route from the current location of the vehicle to the destination based on the map information stored in the main body 82, the current location of the vehicle from the GPS antenna 84, and the destination, and displays the set planned driving route on the display 86 to provide route guidance.

[0021] Next, the operation of the electric vehicle 20 of the embodiment thus configured, particularly the operation when saving the actual predicted difference time ΔT as the difference time between the predicted battery temperature adjustment time Test required to adjust the temperature of the battery 30 to within the temperature range suitable for charging the battery 30 and the actual time when arriving at the destination, will be described. FIG. 2 is a flowchart showing an example of the actual predicted difference time saving process executed by the electronic control unit 50. This process is executed every time a predetermined time Tset elapses after starting the temperature adjustment of the battery 30 by the air conditioner 36 a time Test of predicted battery temperature adjustment before the predicted arrival time at the destination.

[0022] When the actual predicted time difference saving process is executed, the electronic control unit 50 first confirms that the system is turned on and that the temperature control of the battery 30 by the air conditioning unit 36 ​​is turned on (step S100). Then it waits for a predetermined time Tset to elapse (step S110). Once the predetermined time Tset has elapsed, it calculates the predicted battery temperature control time Test (step S120). The predicted battery temperature control time Test can be obtained, for example, by first determining the relationship between the temperature Tb of the battery 30, the outside temperature Tout, the on / off state of the air conditioning in the passenger compartment, the on / off state of the air conditioning in the passenger compartment, and the predicted battery temperature control time Test based on the temperature Tb of the battery 30, the outside temperature Tout, and the on / off state of the air conditioning in the passenger compartment, through experiments or machine learning, and storing it as a predicted battery temperature control time setting map. When the temperature Tb of the battery 30, the outside temperature Tout, and the on / off state of the air conditioning in the passenger compartment are given, the corresponding predicted battery temperature control time Test can be derived from the map.

[0023] When calculating the predicted battery temperature control time Test, the actual predicted difference time ΔT (ΔT = previous Test - current Test - Tset) is calculated by subtracting the currently calculated predicted battery temperature control time Test and a predetermined time Tset from the previously calculated predicted battery temperature control time Test (step S130), and it is determined whether or not the air conditioning unit 36 ​​is turned on (step S140). If it is determined that the air conditioning of the occupant compartment by the air conditioning unit 36 ​​is turned on, it is determined whether or not the currently calculated actual predicted difference time ΔT is the maximum value of the actual predicted difference time ΔT calculated when it was determined that the air conditioning of the occupant compartment by the air conditioning unit 36 ​​was turned on up to that point (step S150). If it is determined that the currently calculated actual predicted difference time ΔT is the maximum value of the actual predicted difference time ΔT calculated up to that point, the battery temperature Tb, outside temperature Tout, the on / off status of the air conditioning in the occupant compartment, and the actual predicted difference time ΔT are updated as air conditioning ON data ΔTon (step S160). Furthermore, if it is determined that the actual predicted difference time ΔT calculated this time is not the maximum value among the actual predicted difference times ΔT calculated up to that point, the air conditioning ON data ΔTon will not be updated.

[0024] If it is determined in step S140 that the air conditioning in the passenger compartment by the air conditioning unit 36 ​​is turned off, it is determined whether the actual predicted difference time ΔT calculated this time is the maximum value of the actual predicted difference time ΔT calculated when it was determined that the air conditioning in the passenger compartment by the air conditioning unit 36 ​​was turned off up to that point (step S170). If it is determined that the actual predicted difference time ΔT calculated this time is the maximum value of the actual predicted difference time ΔT calculated up to that point, the temperature Tb of the battery 30, the outside temperature Tout, the on / off status of the air conditioning in the passenger compartment, and the actual predicted difference time ΔT are updated as air conditioning off data ΔToff (step S180). If it is determined that the actual predicted difference time ΔT calculated this time is not the maximum value of the actual predicted difference time ΔT calculated up to that point, the air conditioning off data ΔToff is not updated.

[0025] Next, it is determined whether the system has been turned off (step S190). If it is determined that the system has been turned off, the air conditioning ON data ΔTon and air conditioning OFF data ΔToff are saved (step S190), and this process is terminated. The air conditioning ON data ΔTon and air conditioning OFF data ΔToff saved here are the maximum values ​​of the actual predicted difference time ΔT calculated each time a predetermined time Tset elapses until the temperature control of the battery 30 by the air conditioning unit 36 ​​is completed. If it is determined in step S190 that the system has not been turned off, this process is terminated without saving the air conditioning ON data ΔTon and air conditioning OFF data ΔToff.

[0026] In the electric vehicle 20 of the embodiment described above, when the air conditioning in the passenger compartment by the air conditioning unit 36 ​​is turned on or when the air conditioning in the passenger compartment by the air conditioning unit 36 ​​is turned off, the actual predicted difference time ΔT is calculated at predetermined intervals by subtracting the currently calculated predicted battery temperature control time Test and a predetermined time Tset from the previously calculated predicted battery temperature control time Test, and the maximum value of this difference is saved as air conditioning on data ΔTon and air conditioning off data ΔToff, along with the battery temperature Tb, the outside temperature Tout, and the on / off status of the passenger compartment air conditioning. The air conditioning on data ΔTon and air conditioning off data ΔToff obtained in this way can be used to calculate the predicted battery temperature control time Test more appropriately, thereby contributing to an improvement in the accuracy of the predicted battery temperature control time Test.

[0027] In the electric vehicle 20 of this embodiment, the actual predicted difference time ΔT is calculated by subtracting the currently calculated predicted battery temperature control time Test and a predetermined time Tset from the previously calculated predicted battery temperature control time Test at predetermined intervals, and the maximum value of this difference is saved as air conditioning on data ΔTon and air conditioning off data ΔToff, along with the battery temperature Tb, outside temperature Tout, and the on / off state of the air conditioning in the passenger compartment. However, the difference time between the predicted battery temperature control time Test calculated before the start of temperature control of the battery 30 by the air conditioning unit 36 ​​and the actual time actually required for temperature control of the battery 30 by the air conditioning unit 36 ​​may also be saved as air conditioning on data ΔTon and air conditioning off data ΔToff, along with the battery temperature Tb, outside temperature Tout, and the on / off state of the air conditioning in the passenger compartment at the start of temperature control.

[0028] The correspondence between the main elements of the embodiment and the main elements of the invention described in the section on means for solving the problem will be explained. In the embodiment, the motor 22 corresponds to "electric motor", the battery 30 corresponds to "battery", the air conditioning device 36 corresponds to "air conditioning device", the navigation device 90 corresponds to "navigation system", and the electronic control unit 50 corresponds to "temperature control device".

[0029] Furthermore, the correspondence between the main elements of the embodiment and the main elements of the invention described in the section on means for solving the problem is merely an example to specifically explain the form in which the embodiment implements the invention described in the section on means for solving the problem, and does not limit the elements of the invention described in the section on means for solving the problem. In other words, the interpretation of the invention described in the section on means for solving the problem should be based on the description in that section, and the embodiment is merely one specific example of the invention described in the section on means for solving the problem.

[0030] Although embodiments for carrying out the present invention have been described above using examples, the present invention is not limited in any way to these embodiments, and can be carried out in various forms without departing from the spirit of the present invention. [Industrial applicability]

[0031] This invention can be used in industries such as electric vehicle manufacturing. [Explanation of Symbols]

[0032] 20 Electric vehicle, 22 Motor, 24 Inverter, 26 Drive shaft, 27 Differential gear, 28a, 28b Drive wheels, 30 Battery, 31a Voltage sensor, 31b Current sensor, 31c Temperature sensor, 32 Bidirectional charging device, 34 Connector, 36 Air conditioning unit, 37 Circulation path, 50 Electronic control unit, 51 CPU, 52 ROM, 53 RAM, 54 Flash memory, 60 Ignition switch, 61 Vehicle speed sensor, 62 Acceleration sensor, 63 Wheel speed sensor, 64 Shift lever, 65 Shift position sensor, 66 Accelerator pedal, 67 Accelerator pedal position sensor, 68 Brake pedal, 69 Brake pedal position sensor, 70 Display device, 72 Communication device, 73 Outside temperature sensor, 80 Navigation device, 82 Main unit, 84 GPS antenna, 86 Display.

Claims

1. An electric motor that inputs and outputs power for propulsion, A battery that exchanges power with the aforementioned electric motor, An air conditioning system that provides air conditioning for the crew compartment and also controls the temperature of the battery, Navigation system and, A temperature control device for controlling the temperature of the aforementioned battery, An electric vehicle equipped with, The temperature control device predicts the battery temperature adjustment time required for the battery temperature to reach a suitable temperature for charging by the air conditioning system when the destination is reached, based on the destination set by the navigation system and the current location, and stores the difference between the predicted battery temperature adjustment time and the actual time required for temperature adjustment by the air conditioning system as the actual predicted time difference. An electric vehicle characterized by the following features.

2. The electric vehicle according to claim 1, The temperature control device calculates the predicted battery temperature control time each predetermined time elapsed since the start of temperature control by the air conditioning device, calculates the predicted time difference obtained by subtracting the currently calculated predicted battery temperature control time from the previously calculated predicted battery temperature control time and the predetermined time each predetermined time elapsed, and stores the maximum value of the predicted time difference calculated each predetermined time elapsed as the actual predicted time difference. Electric car.

3. The electric vehicle according to claim 2, The temperature control device distinguishes and stores the difference in actual predicted time when the temperature of the battery is controlled by the air conditioning system while the crew compartment is being air-conditioned by the air conditioning system, and the difference in actual predicted time when the temperature of the battery is controlled by the air conditioning system while the crew compartment is not being air-conditioned by the air conditioning system. Electric car.

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