Electric vehicle control method and electric vehicle control system

Abstract

Provided is a method for controlling an electric vehicle in which power is supplied and received between a drive motor and a battery, and the charging / discharging power of the battery is limited when the temperature of the battery reaches a predetermined upper limit temperature or falls below a lower limit temperature lower than the upper limit temperature, a load transition indicating a change in the load of the battery when the vehicle travels on a travel path from the current location to the destination is calculated, and a temperature transition of the battery is calculated on the basis of the load transition and the current temperature of the battery. When it is predicted that the temperature of the battery is lower than a lower limit temperature when the load is changed from a low load state to a high load state, the battery is heated before the load is changed to the high load state, and when it is predicted that the temperature of the battery reaches an upper limit temperature when the load is changed to the high load state, the battery is heated. The battery is cooled before the load becomes a high load state.

Description

Technical Field

[0001] The present invention relates to a control method for an electric vehicle and a control system for an electric vehicle. Background Art

[0002] JP4765298B discloses the following, that is, in the case where it is predicted from the travel route of the vehicle that the temperature of the battery is greater than or equal to the appropriate temperature, reservation cooling control for pre-lowering the temperature is implemented. Summary of the Invention

[0003] However, in the case where the temperature of the battery reaches a specified upper limit temperature, the charge / discharge power of the battery is restricted in order to prevent a failure of the battery. Further, in the case where the temperature of the battery is lower than a specified lower limit temperature, the charge / discharge power of the battery for reducing the charge / discharge capacity of the battery is also restricted. Thus, in the case where a high load is requested of the battery when restricting the charge / discharge power of the battery, a situation may occur in which the driver cannot obtain a desired input / output.

[0004] Therefore, an object of the present invention is to provide a control method for an electric vehicle and a control system for an electric vehicle that reduce insufficient input / output when a high load is requested of the battery.

[0005] According to an aspect of the present invention, a control method for an electric vehicle supplies and receives power between a drive motor and a battery, and restricts the charge / discharge power of the battery in the case where the temperature of the battery reaches a specified upper limit temperature or is lower than a lower limit temperature lower than the upper limit temperature. In this control method, based on the travel route from the current location of the vehicle to the destination, at least a low-load travel route on which the vehicle travels in a state where the load on the battery is a low load and a high-load travel route on which the vehicle travels in a state where the load is a high load greater than the low load are estimated, whereby a load transition representing a change in the load on the battery when the vehicle travels on the travel route is calculated, and a temperature transition of the battery is calculated based on the load transition and the current temperature of the battery. Further, in the case where it is predicted that the temperature of the battery will be lower than the lower limit temperature when the load changes from the low-load state to the high-load state, the battery is heated before the load becomes the high-load state, and in the case where it is predicted that the temperature of the battery will reach the upper limit temperature when the load is the high-load state, the battery is cooled before the load becomes the high-load state. Brief Description of the Drawings

[0006] Figure 1 is a block diagram for explaining the structure of a vehicle of a control system for an electric vehicle to which the present embodiment is applied.

[0007] Figure 2 is a block diagram of a control system for an electric vehicle according to the present embodiment.

[0008] Figure 3 It is a graph showing the relationship between the temperature of the battery and the allowable input / output of the battery.

[0009] Figure 4 It is a graph showing the relationship between the state of charge (SOC) of the battery and the allowable input of the battery.

[0010] Figure 5 It is a graph showing the relationship between the state of charge (SOC) of the battery and the allowable output of the battery.

[0011] Figure 6 It is a flowchart (S101 - S109) when the vehicle enters a high-load output driving path in the control system of the electric vehicle in this embodiment.

[0012] Figure 7 It is a flowchart (S110 - S121) before the vehicle enters a regenerative braking driving path or reaches a charging station in the control system of the electric vehicle in this embodiment.

[0013] Figure 8 It is a timing diagram when it is predicted that the vehicle will enter a high-load output driving path and the battery is pre-heated in the control system of the electric vehicle in this embodiment.

[0014] Figure 9 It is a timing diagram when it is predicted that the temperature of the battery will reach the upper limit temperature during the vehicle's driving on a high-load output driving path and the battery is pre-cooled in the control system of the electric vehicle in this embodiment.

[0015] Figure 10 It is a timing diagram when it is predicted that the vehicle will enter a regenerative braking driving path and the battery is pre-heated in the control system of the electric vehicle in this embodiment.

[0016] Figure 11 It is a timing diagram when it is predicted that the temperature of the battery will reach the upper limit temperature during the vehicle's driving on a regenerative braking driving path and the battery is pre-cooled in the control system of the electric vehicle in this embodiment.

[0017] Figure 12 It is a timing diagram when it is predicted that the vehicle will reach a charging station and the battery will be charged, and the battery is pre-heated in the control system of the electric vehicle in this embodiment.

[0018] Figure 13 It is a timing diagram when it is predicted that the temperature of the battery will reach the set temperature during the charging of the battery and the battery is pre-cooled in the control system of the electric vehicle in this embodiment.

[0019] Figure 14This is a flowchart ( S201 - S215 ) in the case where the battery is charged and then the vehicle is driven in the control system of the electric vehicle according to the present embodiment.

[0020] Figure 15 This is a timing chart when the vehicle travels along the low-load travel route and reaches the destination after charging the battery in the electric vehicle control system of the present embodiment. DETAILED DESCRIPTION

[0021] [Structure of Vehicle 100]

[0022] Figure 1 1 is a block diagram for explaining the structure of a vehicle 100 to which the control system of an electric vehicle of the present embodiment is applied. The vehicle 100 is an electric vehicle. An electric vehicle refers to a vehicle that has a drive motor (hereinafter referred to as motor 4) as a drive source and travels due to the torque generated by the motor 4 at one or more wheels to generate a driving force. Therefore, in addition to the so-called electric vehicle, the electric vehicle also includes a hybrid vehicle that uses the motor 4 and the engine as a drive source. For example, the electric vehicle also includes a hybrid vehicle that uses the motor 4 as a drive source for any one of the front wheels and the rear wheels and uses the engine as a drive source for the other wheel. In addition, a four-wheel drive vehicle refers to a vehicle that uses four wheels as drive wheels 9. In addition to the vehicle that always uses the four wheels as drive wheels 9, the four-wheel drive vehicle includes a vehicle that can switch between two-wheel drive and four-wheel drive, which are so-called front-wheel drive or rear-wheel drive. In addition, the four-wheel drive vehicle can make part of the four wheels linked and controlled as drive wheels 9, and sometimes the four wheels are controlled as drive wheels 9 driven independently. Therefore, in the present embodiment, the electric four-wheel drive vehicle refers to a vehicle 100 that travels by causing a part or all of the four wheels to generate a driving force due to the torque generated by the motor 4 .

[0023] like Figure 1 As shown, the vehicle 100 is an electric four-wheel drive vehicle, but it may also be an electric two-wheel drive vehicle using only the front wheels or an electric two-wheel drive vehicle using only the rear wheels. The vehicle 100 includes a front drive system fds, a rear drive system rds, a battery 1, and a controller 2 (control unit).

[0024] The front drive system fds receives power supply from the battery 1 and drives the front wheels 9f under the control of the controller 2. The front drive system fds includes a front inverter 3f, a front drive motor 4f, a front speed reducer 5f, a front rotation sensor 6f, a front drive shaft 8f, the front wheels 9f, etc. The suffix f indicates the structure on the front side. The front wheels 9f are a pair of wheels that are relatively in the front of the four wheels of the vehicle 100. The front of the vehicle 100 refers to the specified direction formally defined according to the orientation of the driver's seat, etc. The front drive system fds makes the front wheels 9f act as the drive wheels 9 that generate the driving force of the vehicle 100.

[0025] The rear drive system rds receives power supply from the battery 1 and drives the rear wheels 9r under the control of the controller 2. The rear drive system rds symmetrically includes a rear inverter 3r, a rear drive motor 4r, a rear speed reducer 5r, a rear rotation sensor 6r, a rear drive shaft 8r, the rear wheels 9r. The suffix r indicates the structure on the rear side. The rear wheels 9r are a pair of wheels that are relatively in the rear of the four wheels of the vehicle 100. The rear of the vehicle 100 refers to the direction opposite to the front of the vehicle 100. The rear drive system rds makes the rear wheels 9r act as the drive wheels 9 that generate the driving force of the vehicle 100.

[0026] The battery 1 is connected to the motor 4 via the inverter 3 and supplies driving power to the motor 4 by discharging. In addition, the battery 1 can receive the supply of regenerative power from the motor 4 and be charged. In the front drive system fds, the battery 1 is connected to the front drive motor 4f via the front inverter 3f. Similarly, in the rear drive system rds, the battery 1 is connected to the rear drive motor 4r via the rear inverter 3r.

[0027] The controller 2 is a control device of the vehicle 100 and is a computer composed of a central processing unit (CPU), a read-only memory (ROM), a random access memory (RAM), an input / output interface (I / O interface), etc. The controller 2 generates control signals for controlling the front drive motor 4f and the rear drive motor 4r based on the vehicle variables of the vehicle 100. The vehicle variables refer to the information indicating the operating state or control state of the whole vehicle 100 or each part constituting the vehicle 100, and can be obtained through detection, measurement, or calculation, etc. For example, in addition to the accelerator opening APO, longitudinal G and lateral G, vehicle speed V, slope value, steering angle, wheel speed described later, the vehicle variables also include the rotational speeds Nmf, Nmr of the respective motors 4f, 4r, three-phase alternating current, etc. The controller 2 controls the front drive motor 4f and the rear drive motor 4r respectively using the above vehicle variables.

[0028] The front inverter 3f and the rear inverter 3r turn on / off the switching elements according to the drive signals generated by the controller 2, thereby converting the DC current supplied from the battery 1 into an AC current, and respectively adjusting the current supplied to the front drive motor 4f and the rear drive motor 4r. In addition, each of the inverters 3f, 3r inversely converts the AC current generated by the front drive motor 4f and the rear drive motor 4r into a DC current using the regenerative braking force, and adjusts the current supplied to the battery 1.

[0029] The front drive motor 4f and the rear drive motor 4r are, for example, three-phase AC motors, and generate a driving force (torque T) using the AC current supplied from the connected inverter 3. The driving force generated by the front drive motor 4f is transmitted to the front wheel 9f via the front speed reducer 5f and the front drive shaft 8f. Similarly, the driving force generated by the rear drive motor 4r is transmitted to the rear wheel 9r via the rear speed reducer 5r and the rear drive shaft 8r. The front drive motor 4f and the rear drive motor 4r generate a regenerative braking force when rotated by the front wheel 9f and the rear wheel 9r respectively, and recover the kinetic energy of the vehicle 100 as electric energy. The front drive motor 4f constitutes a drive source (front drive source) for driving the front wheel 9f. Similarly, the rear drive motor 4r constitutes a drive source (rear drive source) for driving the rear wheel 9r independently of the front wheel 9f.

[0030] The front speed reducer 5f and the rear speed reducer 5r are composed of, for example, a plurality of gears. Each of the above speed reducers 5f, 5r reduces the rotational speed Nm of the connected motor 4 and transmits it to the drive shaft 8, thereby generating a drive torque or a braking torque proportional to the reduction ratio. The front rotation sensor 6f and the rear rotation sensor 6r detect the rotor phase of the connected motor 4 and output it to the controller 2. Regarding the controller 2, the rotational speed Nmf of the front drive motor 4f is detected based on the output of the front rotation sensor 6f, and the rotational speed Nmr of the rear drive motor 4r is detected based on the output of the rear rotation sensor 6r. The front current sensor 7f and the rear current sensor 7r detect the current flowing through the connected motor 4 and output it to the controller 2. In the present embodiment, the current sensors 7f, 7r detect the three-phase AC currents of the motors 4f, 4r respectively.

[0031] In addition to the aforementioned front rotation sensor 6f, front current sensor 7f, rear rotation sensor 6r, and rear current sensor 7r, the vehicle 100 also has various sensors 15. For example, in addition to the accelerator opening sensor 15a, acceleration sensor 15b, and vehicle speed sensor 15c, the various sensors 15 also include a slope sensor, a steering operation angle sensor, a wheel speed sensor, and the like. The accelerator opening sensor 15a detects the accelerator opening APO as the accelerator operation amount. The acceleration sensor 15b detects the acceleration in the front-rear direction and the lateral direction of the vehicle 100, that is, the front-rear G and the lateral G. The vehicle speed sensor 15c detects the vehicle speed V of the vehicle 100. The vehicle speed V is the moving speed of the entire vehicle body of the vehicle 100, that is, the body speed. The slope sensor detects the slope value as the slope of the traveling road of the vehicle 100. The steering operation angle sensor detects the steering operation angle of the steering wheel. The wheel speed sensor detects the wheel speed of each drive wheel 9. The detection values detected by the various sensors 15 are input to the controller 2.

[0032] In the vehicle 100, the target drive torque T_req, which is the requested torque of the driver, is distributed to the front wheels 9f and the rear wheels 9r. Therefore, if either the front torque distribution value RTf, which is the torque distribution value RT of the front wheels 9f, or the rear torque distribution value RTr, which is the torque distribution value RT of the rear wheels 9r, is determined, the other is also determined. As a result, the torque distribution of the front and rear wheels 9f, 9r is also determined. Therefore, in the vehicle 100, as described later, the rear torque Tr of the rear drive motor 4r is calculated based on the operating state represented by the first parameters such as the front-rear G. Thus, a state in which the rear torque distribution value RTr can be calculated is formed, and the rear torque distribution value RTr is substantially calculated to perform the torque distribution control of the front and rear wheels 9f, 9r.

[0033] [Structure of the control system]

[0034] Figure 2 is a block diagram of the control system of the electric vehicle according to the present embodiment. Figure 3 is a diagram showing the relationship between the temperature of the battery 1 and the input / output characteristics of the battery 1. Figure 4 is a diagram showing the relationship between the state of charge (SOC) of the battery 1 and the input characteristics of the battery 1. Figure 5 is a diagram showing the relationship between the state of charge (SOC) of the battery 1 and the output characteristics of the battery 1.

[0035] The control system of the electric vehicle according to the present embodiment is composed of a navigation device 20, an EV controller 21, a battery controller 22, an air conditioning device 23 (HVAC: Heating Ventilation Air Conditioning), a cooling device (cooler 25, radiator 24), and a heater 26.

[0036] The air conditioner 23 has an air conditioner for conditioning the interior of the vehicle and an air conditioner heat exchange circuit that circulates a refrigerant (e.g., Freon such as HFC134a) for heat exchange. The air conditioner heat exchange circuit includes: a compressor that compresses the refrigerant gas and discharges the compressed refrigerant gas at high temperature and high pressure; a condenser that exchanges heat between the compressed refrigerant gas and outside air, releases the heat of the compressed refrigerant gas to the outside air to cool / condense the compressed refrigerant gas and form a liquid refrigerant; an expansion valve that expands the high-pressure liquid refrigerant to form a low-pressure / low-temperature liquid refrigerant; and an evaporator that exchanges heat between the liquid refrigerant and the interior air of the vehicle, absorbs the heat of the interior air of the vehicle to cool the interior air of the vehicle, and evaporates the liquid refrigerant to form a refrigerant gas.

[0037] A first circulation circuit (not shown) that circulates a refrigerant (water) for cooling the battery 1 in the cooler 25 and a second circulation circuit (not shown) that circulates a refrigerant (water) for cooling the battery 1 in the radiator 24 are connected in parallel to the battery 1.

[0038] The cooler 25 connects, for example, a branch circuit (not shown) branched from the air conditioner heat exchange circuit and the first circulation circuit, and exchanges heat between the refrigerant (Freon) circulating in the branch circuit and the refrigerant (water) circulating in the first circulation circuit. In addition, when the cooler 25 does not cool the battery 1, the drive of the compressor (not shown) of the cooler 25 is stopped.

[0039] In addition, a drive system circulation circuit (not shown) that circulates a refrigerant (water) for cooling the motor 4 and the inverter 3 is installed in the vehicle 100. A radiator 24 is arranged in the drive system circulation circuit, and the radiator 24 exchanges heat between the refrigerant and outside air. In addition, a second circulation circuit branches from the drive system circulation circuit, and the second circulation circuit circulates the refrigerant cooled by the radiator 24 in the battery 1. In addition, when the battery 1 is not cooled by the radiator 24, an on-off valve (not shown) arranged in the second circulation circuit is closed or the drive of the circulation pump that circulates the refrigerant is stopped.

[0040] The heater 26 is, for example, a PTC (Positive Temperature Coefficinet) heater, and is arranged in contact with the battery 1 or a heat capacity body in contact with the battery 1 to heat the battery 1.

[0041] As described above, the battery 1 supplies power to the motor 4, and also supplies power to the compressor (not shown) of the cooler 25, the circulation pump (not shown) and the on-off valve (not shown) of the drive system circulation circuit, and the heater 26.

[0042] The navigation device 20 generates map information including information on the driving route from the current location (or departure location) of the vehicle 100 to the destination (or via point), and outputs it to the EV controller 21. Information on the current location (departure location) of the vehicle 100 is obtained, for example, by GPS (Global Positioning System), and is obtained by matching on the roads in the map information possessed by the navigation device 20. Information on the destination is obtained by determining the destination on the map information through the driver's input operation. Here, the destination is, for example, the final location of the navigation and is the position where the entire vehicle system stops. Information on the driving route is obtained by the navigation device 20 selecting a route connecting the current location (departure location) and the destination in the map information. The map information (information on the driving route) includes information on the distance to the destination, information on the positions of the roads constituting the driving route, information on the gradients of the roads, information on the elevation difference, traffic information, etc. Traffic information includes, for example, information on the attributes of the roads (ordinary roads, highways), information on the predicted vehicle speeds on the roads (statutory speed limits, statistical average vehicle speeds), information on charging stations (locations, charger outputs, attributes (ordinary roads, highways)), etc.

[0043] The battery controller 22 includes the front inverter 3f and the rear inverter 3r, and controls the supply and reception of power between the battery 1 and the motor 4. In addition, if a charger (charging plug) disposed at the charging station is inserted into the insertion port for the charging plug disposed on the vehicle 100, the battery controller 22 detects the charging plug and supplies the output from the charger to the battery 1 to charge the battery 1. Further, the battery controller 22 detects the state of charge (SOC) and temperature of the battery 1, and outputs this information to the EV controller 21.

[0044] The battery controller 22 monitors the temperature of the battery 1. If the temperature of the battery 1 is higher than the specified upper limit temperature (T max : the heat-resistant upper limit temperature of the battery 1) or lower than the lower limit temperature (T min : the temperature at which the input and output of the battery 1 start to decrease), the allowable input and output [kW] of the battery 1 is restricted to protect the battery 1 from deterioration. In addition, regarding the battery controller 22, during charging of the battery 1, if the temperature of the battery 1 is higher than the specified set temperature (T1), the allowable input [kW] of the battery 1 can be restricted. Here, the set temperature (T1) is the same temperature as the upper limit temperature (T max ) or a temperature between the upper limit temperature (T max ) and the first intermediate temperature (T mid1 ) described later.

[0045] In addition, when the vehicle system stops and the outside air is less than or equal to the lower limit temperature (Tmin ) In some cases, the temperature of the battery 1 may be less than or equal to the lower limit temperature (T min ). Additionally, in some cases, a relatively high load is applied to the battery 1 for a long time, causing the temperature of the battery 1 to reach the upper limit temperature.

[0046] In addition, in Figure 3 , the magnitude of the allowable input / output between the upper limit temperature (T max ) and the lower limit temperature (T min ) corresponds to the output of the battery 1 in the high load output driving path and the input of the battery 1 in the regenerative braking driving path, which will be described later. Moreover, in Figure 3 , the input characteristics and output characteristics of the battery 1 are the same, but they can also have different characteristics.

[0047] The battery controller 22 can control the cooling device and the heater 26 in such a way that the temperature of the battery 1 is within an appropriate temperature range, as will be described later.

[0048] As Figure 4 shown, the battery controller 22 monitors the state of charge of the battery 1. If the state of charge (SOC) of the battery 1 is higher than a specified upper limit value (S max : for example, 80 [%]), the allowable input [kW] of the battery 1 is restricted to prevent overcharging of the battery 1.

[0049] As Figure 5 shown, the battery controller 22 monitors the state of charge of the battery 1. If the temperature of the battery 1 is lower than a specified lower limit value (S min : for example, 20 [%]), the allowable output [kW] of the battery 1 is restricted to prevent the state of charge from becoming zero.

[0050] The EV controller 21 includes the controller 2. The EV controller 21 inputs map information including information on the driving path from the current location (or the starting location) to the destination from the navigation device 20, and estimates the low load driving path, the high load driving path (high load output driving path, regenerative braking driving path), and the charging station, and calculates the above information. In addition, the information of the charging station includes location information, charger output information, and attribute information (ordinary road, highway).

[0051] The low load driving path generally refers to a path where the vehicle 100 travels at a low speed on a road with a road gradient (uphill, downhill) lower than a specified inclination angle and is approximately flat (for example, an ordinary road), enabling the vehicle 100 to travel in a state where the load on the battery 1 is a low load.

[0052] The high-load output driving path is equivalent to the following path, that is, when the battery 1 supplies power to the motor 4, for example, on a road (ordinary road, highway) where the road slope is higher than a specified inclination angle and the uphill state continues for a distance greater than or equal to a specified distance (e.g., 1 km), or a road (especially a highway) where the speed limit or average vehicle speed is set to be greater than or equal to a specified speed (e.g., 100 [km / h]) and the length reaches a distance greater than or equal to a specified distance (e.g., 1 km), the vehicle 100 can drive in a state where the load on the battery 1 is high load.

[0053] The regenerative braking driving path is equivalent to the following path, that is, when regenerative power is supplied from the motor 4 to the battery 1, for example, when the vehicle 100 is driving on a road where the downhill state with a road slope higher than a specified inclination angle continues for a distance greater than or equal to a specified distance (e.g., 1 km) or in an area including the boundary between a highway and an ordinary road, relatively large regenerative braking accompanied by regenerative power is performed on the vehicle 100.

[0054] The charging station is a facility for charging the battery 1 of the vehicle 100, and the battery 1 becomes a high-load state during charging.

[0055] The EV controller 21 stores the information of multiple driving paths obtained in the past, and also stores the information of the low-load driving path, the high-load output driving path, the regenerative braking driving path, and the information of the charging station associated with the information of each driving path.

[0056] The EV controller 21 compares the information of the last input driving path with the information of the past driving paths. When there is information of a past driving path that is consistent with the information of the last input driving path, it is also preferable to extract the information of the low-load driving path, the high-load output driving path, the regenerative braking driving path, and the information of the charging station associated with the information of this driving path.

[0057] However, it is known that the driving path of the vehicle 100 from the current location (or the departure location) to the destination is a monotonic terrain, and sometimes it is known that the load (input / output) on the battery 1 is approximately constant. In this case, the EV controller 21 can also estimate the low-load driving path or the high-load output driving path based on the load on the battery 1 at the current location or the average value of the load on the battery 1 from the departure location to the current location. Thereby, the processing burden on the EV controller 21 can be reduced.

[0058] The EV controller 21 calculates a load trend indicating changes in the load on the battery 1 when the vehicle 100 travels along a driving route, based on information about a low-load driving route, a high-load output driving route, a regenerative braking driving route, and charging stations configured along the driving route.

[0059] The EV controller 21 calculates the temperature trend of the battery 1 based on the load trend and the current temperature of the battery 1. More specifically, the EV controller 21 predicts the temperature trend of the battery 1 when the vehicle 100 travels from the current location to a specified monitoring distance (e.g., 10 [km]) based on the current temperature of the battery 1. Of course, the EV controller 21 can predict the temperature trend of the battery 1 when the vehicle 100 travels from the current location to the destination.

[0060] When the EV controller 21 predicts that the temperature of the battery 1 will be lower than the lower limit temperature (T min) when the load changes from a low-load state to a high-load state, it performs control to heat the battery 1 before the load becomes high.

[0061] That is, when the EV controller 21 predicts that the temperature of the battery 1 will be lower than the lower limit temperature (T min ) when the vehicle 100 enters a high-load output driving route as described later, it performs control to heat the battery 1 before the vehicle 100 enters the high-load output driving route, thereby reducing the output shortage of the battery 1 (insufficient driving force of the vehicle 100).

[0062] When the EV controller 21 predicts that the temperature of the battery 1 will reach the upper limit temperature (T max ) when the load is in a high-load state, it performs control to cool the battery 1 before the load becomes high.

[0063] That is, when the EV controller 21 predicts that the temperature of the battery 1 will reach the upper limit temperature (T max ) during the travel of the vehicle 100 on a high-load output driving route, it performs control to cool the battery 1 before the vehicle 100 enters the high-load output driving route, thereby reducing the output shortage of the battery 1 (insufficient driving force of the vehicle 100).

[0064] When the EV controller 21 predicts that the temperature of the battery 1 will reach the upper limit temperature (T max ) during the travel of the vehicle 100 on a regenerative braking driving route as described later, it performs control to cool the battery 1 before the vehicle 100 enters the regenerative braking driving route, thereby reducing the input shortage of the battery 1 (insufficient regenerative braking force) and increasing the charging rate of the battery 1.

[0065] When it is predicted as described later that the charging rate (SOC) of the battery 1 reaches the upper limit value (S max : for example, 80 [%]) during the regenerative braking driving of the vehicle 100, the EV controller 21 performs control to cool the battery 1 before the vehicle 100 enters the regenerative braking driving path, thereby reducing the input shortage (insufficient regenerative braking force) of the battery 1 and reducing the frequency of the temperature of the battery 1 reaching the upper limit temperature (T max ) during the regenerative braking driving of the vehicle 100.

[0066] When it is predicted as described later that the temperature of the battery 1 is lower than the lower limit temperature (T min ) when the vehicle 100 enters the regenerative braking driving path, the EV controller 21 performs control to heat the battery 1 before the vehicle 100 enters the regenerative braking driving path, thereby reducing the input shortage (insufficient regenerative braking force) of the battery 1.

[0067] When it is predicted as described later that the temperature of the battery 1 is lower than the lower limit temperature (T min ) when the vehicle 100 arrives at the charging station, the EV controller 21 performs control to heat the battery 1 before the vehicle 100 arrives at the charging station, thereby reducing the input shortage (charging time of the battery 1).

[0068] When it is predicted as described later that the temperature of the battery 1 reaches the set temperature (T1) during the charging of the battery 1, the EV controller 21 performs control to cool the battery 1 before the vehicle 100 arrives at the charging station, thereby reducing the input shortage of the battery 1 and shortening the charging time of the battery 1.

[0069] The EV controller 21 controls to keep the temperature of the battery 1 within an appropriate temperature range higher than the lower limit temperature (T min ) and lower than the upper limit temperature (T max ). If the temperature of the battery 1 is greater than or equal to the first intermediate temperature (T max ) between the upper limit temperature (T min ) and the lower limit temperature (T mid1 ), the cooling of the battery 1 is started, and then the cooling of the battery 1 that keeps the temperature of the battery 1 less than or equal to the second intermediate temperature (T mid1 ) between the first intermediate temperature (T min ) and the lower limit temperature (T mid2 ) is stopped. In addition, the EV controller 21 can perform the following control, that is, if the temperature of the battery 1 is greater than or equal to the intermediate temperature (T max ) between the upper limit temperature (T min ) and the lower limit temperature (T mid), then the cooling of battery 1 starts, and then if the temperature of battery 1 is lower than the intermediate temperature (T mid ), the cooling of battery 1 stops.

[0070] When the temperature of the outside air is greater than or equal to the specified threshold temperature, the EV controller 21 cools battery 1 using the cooler 25. In this case, the EV controller 21 turns on the compressor of the cooler 25 and closes the on-off valve. In addition, when the temperature of the outside air is lower than the threshold temperature, the EV controller 21 cools battery 1 using the radiator 24. In this case, the EV controller 21 stops the compressor of the cooler 25 and opens the on-off valve (turns on the circulation pump).

[0071] Moreover, the EV controller 21 is set such that the higher the load of battery 1, the lower the threshold temperature, and conversely, the lower the load, the higher the threshold temperature.

[0072] When the EV controller 21 predicts that the vehicle 100 enters a low-load driving path and the end point of this low-load driving path is the destination of the vehicle 100, the cooling of battery 1 stops regardless of the temperature of battery 1. Thereby, when the temperature of the outside air is greater than or equal to the threshold temperature, the control of cooling battery 1 using the cooler 25 is avoided to reduce power consumption.

[0073] In addition, as chargers at charging stations, there are slow chargers and fast chargers. The slow charger has an output voltage of 100 [V] AC, for example, and converts this output voltage to 400 [V] DC via the charger mounted on the vehicle 100 and supplies it to battery 1. In addition, the fast charger has an output voltage of 400 [V] DC and directly supplies the power of this output voltage to battery 1. In the present embodiment, it is assumed that the charging station on the driving path is a fast charger, but a slow charger can also be applied.

[0074] [First Control Flow]

[0075] Figure 6 It is a flowchart (S101 - S109) when the vehicle 100 enters a high-load output driving path in the control system of the electric vehicle in the present embodiment. Figure 7 It is a flowchart (S110 - S121) when the vehicle 100 enters a regenerative braking driving path or before the vehicle 100 reaches a charging station in the control system of the electric vehicle in the present embodiment.

[0076] The first control process is the control process in the case where the vehicle 100 heats or cools the battery 1 during driving on a low-load driving path and before entering a high-load output driving path or a regenerative braking driving path, or in the case where the vehicle 100 heats or cools the battery 1 before reaching a charging station. In addition, for simplicity of description, the road on which the vehicle 100 initially travels is set as a low-load driving path, but in the present invention, the types of driving paths on which the vehicle 100 travels before entering a high-load output driving path and a regenerative braking driving path, and the types of driving paths on which the vehicle 100 travels before reaching a charging station are arbitrary respectively.

[0077] In step S101, the EV controller 21 acquires information on the driving path from the current location (or departure location) of the vehicle 100 to the destination from the navigation device 20.

[0078] In step S102, based on the information on the driving path, the EV controller 21 estimates information on the low-load driving path, information on the high-load output driving path, information on the regenerative braking driving path, and information on the charging station according to the driving path from the current location of the vehicle 100 to a specified monitoring distance (for example, 10 [km]), and calculates a load trend indicating the change in the load of the battery 1 when the vehicle 100 travels on this driving path.

[0079] In step S103, the EV controller 21 estimates the temperature trend of the battery 1 when the vehicle 100 travels the monitoring distance based on the load trend and the current temperature of the battery 1. For example, the temperature trend of the battery 1 is calculated based on the time integral of the load trend and the difference between the heat dissipation amount based on the temperature difference between the battery 1 and the external air.

[0080] In step S104, the EV controller 21 determines whether the charge rate (SOC) of the battery 1 is lower than the lower limit value (S min ). If it is YES, it goes to "Return", and if it is NO, it goes to step S105.

[0081] In step S105, the EV controller 21 calculates whether to enter a high-load output driving path. If it is YES, it goes to step S105, and if it is NO, it goes to step S110.

[0082] In step S106, the EV controller 21 determines whether, if the temperature of the battery 1 is lower than the lower limit temperature (T min ) when the vehicle 100 enters a high-load output driving path, it is predicted that the vehicle 100 is traveling on a low-load driving path. If it is YES, it goes to step S107, and if it is NO, it goes to step S108.

[0083] In step S107, the EV controller 21 heats the battery 1 before the vehicle 100 enters the high-load output driving path. Then, if the temperature of the battery 1 rises to the lower limit temperature (T min ) before the vehicle 100 enters the high-load output driving path, the heating of the battery 1 is stopped and "Return" is entered.

[0084] In step S108, the EV controller 21 determines whether it is predicted that the vehicle 100 is traveling on the low-load driving path if the temperature of the battery 1 reaches the upper limit temperature (T max ) while the vehicle 100 is traveling on the high-load output driving path. If YES, step S109 is entered; if NO, "Return" is entered.

[0085] In step S109, the EV controller 21 cools the battery 1 before the vehicle 100 enters the high-load output driving path. At this time, the timing of starting the cooling of the battery 1 is set in such a way that the vehicle 100 enters the high-load output driving path at the timing when the temperature of the battery 1 drops to the lower limit temperature (T min ). Moreover, the cooling of the battery 1 continues even after the vehicle 100 enters the high-load output driving path.

[0086] In step S110, the EV controller 21 determines whether it enters the regenerative braking driving path. If YES, step S111 is entered; if NO, step S117 is entered.

[0087] In step S111, it is determined whether it is predicted that the vehicle 100 is traveling on the low-load driving path if the temperature of the battery 1 is lower than the lower limit temperature (T min ) when the vehicle 100 enters the regenerative braking driving path. If YES, step S112 is entered; if NO, step S114 is entered.

[0088] In step S112, the EV controller 21 determines whether the total amount of electric power required to heat the temperature of the battery 1 to the lower limit temperature (T min ) (total battery heating power) is higher than the power generated from the time when the temperature of the battery 1 is heated to the lower limit temperature (T min) after which the total amount of regenerative power obtained by the vehicle 100 when traveling on the regenerative braking driving path minus the total amount of regenerative power obtained when the vehicle 100 travels on the regenerative braking driving path without performing heating of the battery 1 before the vehicle 100 enters the regenerative braking driving path (the total amount of regenerative power increase amount), if NO, then proceed to step S113, if YES, then proceed to "return". In addition, when the vehicle 100 travels downhill, the total amount of regenerative power is calculated based on the inclination angle of the downhill, the length (distance) of the downhill, the predicted vehicle speed of the downhill (the predicted torque of the motor 4), and the temperature change of the battery 1 when the vehicle 100 travels downhill.

[0089] In step S113, the EV controller 21 heats the battery 1 before the vehicle 100 enters the regenerative braking travel path. Then, if the temperature of the battery 1 rises to the lower limit temperature (T min ), the heating of battery 1 is stopped and the process enters “return”.

[0090] In step S114, the EV controller 21 determines whether the temperature of the battery 1 reaches the upper limit temperature (T max ) then it is predicted that the vehicle 100 is traveling on a low-load driving route, if it is YES, the process proceeds to step S115, and if it is NO, the process proceeds to "Return".

[0091] In step S115, the EV controller 21 determines whether to cool the temperature of the battery 1 to the lower limit temperature (T min ) is greater than the total amount of power required to cool the battery 1 to the lower limit temperature (T min ) after which the total amount of regenerative electric power obtained by the vehicle 100 when traveling on the regenerative braking driving path minus the total amount of regenerative electric power obtained by the vehicle 100 when traveling on the regenerative braking driving path due to the cooling of the battery 1 before the vehicle 100 enters the regenerative braking driving path (the increase in the total amount of regenerative electric power) is obtained. If the answer is NO, the process proceeds to step S116; if the answer is YES, the process proceeds to "Return".

[0092] In step S116, the EV controller 21 cools the battery 1 before the vehicle 100 enters the regenerative braking driving path. At this time, the temperature of the battery 1 is reduced to the lower limit temperature (T min ) in such a way that the vehicle 100 enters the regenerative braking travel path, the timing of starting cooling of the battery 1 is set. Moreover, even if the vehicle 100 enters the regenerative braking travel path, the cooling of the battery 1 is continued.

[0093] In step S117, the EV controller 21 determines whether there is a charging station at the driving destination of the vehicle based on the information of the driving route, that is, whether the vehicle is heading towards a charging station. If the answer is YES, it proceeds to step S118; if the answer is NO, it proceeds to "Return".

[0094] In step S118, it is determined whether, if the temperature of battery 1 is lower than the lower limit temperature (T min ) when vehicle 100 arrives at the charging station, it is predicted that vehicle 100 is traveling on a low-load driving route. If the answer is YES, it proceeds to step S119; if the answer is NO, it proceeds to step S120.

[0095] In step S119, the EV controller 21 heats battery 1 before vehicle 100 arrives at the charging station. Then, if the temperature of battery 1 rises to the lower limit temperature (T min ) before vehicle 100 arrives at the charging station, the heating of battery 1 is stopped and it proceeds to "Return".

[0096] In step S120, the EV controller 21 refers to the information of the charging station (charger output information) and determines whether, if the temperature of battery 1 reaches the set temperature (T1) during the charging of battery 1, it is predicted that vehicle 100 is traveling on a low-load driving route. If the answer is YES, it proceeds to step S121; if the answer is NO, it proceeds to "Return".

[0097] In step S121, the EV controller 21 cools battery 1 before vehicle 100 arrives at the charging station. Then, the cooling of battery 1 is continued after vehicle 100 arrives at the charging station and after the charging starts.

[0098] [First Timing Diagram]

[0099] Figure 8 This is a timing diagram in the case where it is predicted that vehicle 100 enters a high-load output driving route in the control system of the electric vehicle of the present embodiment and battery 1 is heated in advance. In addition, including the subsequent drawings, the EV controller 21 predicts the vehicle speed, the temperature of battery 1, the input / output of battery 1, and the SOC of battery 1 indicated by the thick dashed line.

[0100] At time t0, vehicle 100 is traveling on a low-load driving route.

[0101] In addition, at t0, the EV controller 21 predicts that vehicle 100 enters a high-load output driving route (e.g., highway) at time t3, but the temperature of battery 1 (dashed line) at this time is lower than the lower limit temperature (T min ).

[0102] Therefore, the EV controller 21 starts heating battery 1 at time t1.

[0103] At time t2, the temperature of battery 1 (solid line) rises to the lower limit temperature (T min ), and thus the EV controller 21 stops heating battery 1.

[0104] At time t3, the vehicle 100 enters a high-load output driving path, and the output of battery 1 (solid line) increases due to the driver's accelerator operation. However, the temperature of battery 1 is higher than the lower limit temperature (T min ), and the output of battery 1 is not restricted, so the output of battery 1 (solid line) and the vehicle speed (solid line) requested by the driver can be obtained.

[0105] On the other hand, in the case where battery 1 is not heated beforehand (before time t3), from time t0 to time t3, the temperature of battery 1 (dashed line) becomes lower than the lower limit temperature (T min ). Moreover, if the vehicle enters a high-load output driving path at time t3, the output of battery 1 increases, and thus the temperature of battery 1 (dashed line) also starts to increase. However, at time t4, according to Figure 3 the allowable output of battery 1 shown (the part lower than T min ), the output of battery 1 is restricted, so the output of battery 1 (dashed line) and the vehicle speed (dashed line) are restricted and are lower than the output of battery 1 (solid line) and the vehicle speed (solid line), respectively.

[0106] At time t5, the temperature of battery 1 (dashed line) becomes the lower limit temperature (T min ), and thus the restriction on the output of battery 1 is released. However, it can be seen that the output of battery 1 is restricted during the period from time t4 to time t5, and the output of battery 1 (dashed line) and the vehicle speed (dashed line) requested by the driver cannot be obtained.

[0107] [Second timing diagram]

[0108] Figure 9 is a timing diagram in the control system of the electric vehicle according to the present embodiment, in the case where it is predicted that the temperature of battery 1 reaches the upper limit temperature (T max ) during the driving of the vehicle 100 on a high-load output driving path and battery 1 is cooled beforehand.

[0109] At time t0, the vehicle 100 is driving on a low-load driving path. In addition, the temperature of battery 1 becomes a temperature between the intermediate temperature (T mid ) and the lower limit temperature (T min ).

[0110] At time t0, the EV controller 21 predicts the temperature change of the battery 1. At time t2, the vehicle 100 enters a high-load output driving route and the output of the battery 1 increases, causing the temperature of the battery 1 (dashed line) to increase. At time t3, the battery 1 is cooled by the cooler 25 (or the radiator 24) (dashed line), causing the temperature of the battery 1 to increase at a higher speed ( Figure 9 The slope of the line representing the temperature of the battery 1) slightly decreases, but the temperature of the battery 1 reaches the upper limit temperature (T max ), therefore according to Figure 3 The allowable output (above T max The output of battery 1 is limited, and it is predicted that the vehicle speed is also limited.

[0111] Therefore, at time t1 , the EV controller 21 starts cooling of the battery 1 by the cooler 25 (or the radiator 24 ) (solid line).

[0112] At time t2, when the temperature of the battery 1 decreases to the lower limit temperature (T min ) at the timing of the vehicle 100 entering the high load output travel route. At this time, the EV controller 21 continues cooling the battery 1 by the cooler 25 (or the radiator 24).

[0113] At time t5, if the temperature of the battery 1 reaches the upper limit temperature (T max ), then according to Figure 3 The allowable output (higher than T max The output of battery 1 and the vehicle speed are limited due to the time t5 that lags behind time t4. Therefore, it can be seen that compared with the case where battery 1 is not cooled in advance (before time t2) (dashed line), the output of battery 1 and the vehicle speed requested by the driver in the high-load output driving route can be maintained for a long time.

[0114] However, in Patent Document 1, the cooling start point (cooling fan operation start timing) is calculated based on the battery temperature and the distance to the point where the charge and discharge amount increases, so the battery temperature is sometimes rising and sometimes falling. When the cooling fan is started when the battery temperature rises sharply, its cooling capacity is consumed in order to suppress the sharp rise in temperature. Therefore, in order to further lower the temperature after suppressing the temperature rise, a higher cooling capacity is requested for the cooling fan. As a result, there is a problem that more power is consumed and the power consumption is deteriorated.

[0115] However, in the present embodiment, the battery 1 is cooled to a required temperature before the temperature of the battery 1 rises suddenly due to a high load applied to the battery 1 , so that power consumption can be reduced compared to the case where the battery 1 is cooled immediately after the temperature rises.

[0116] [3rd Timing Diagram]

[0117] Figure 10 This is a timing diagram in the control system of the electric vehicle according to this embodiment, when it is predicted that the vehicle 100 will enter the regenerative braking driving path and the battery 1 is pre-heated in advance.

[0118] At time t0, the vehicle 100 is driving on the low-load driving path (or high-load output driving path).

[0119] In addition, at t0, the EV controller 21 predicts that the vehicle 100 will enter the regenerative braking driving path at time t3 (the vehicle 100 is driving downhill while applying regenerative braking force), but the temperature of the battery 1 at this time (dashed line) is lower than the lower limit temperature (T min ).

[0120] Therefore, the EV controller 21 starts heating the battery 1 at time t1. In addition, the battery 1 realizes the power for heating the battery 1 (the power of the heater 26).

[0121] At time t2, the EV controller 21 raises the temperature of the battery 1 (solid line) to the lower limit temperature (T min ), so the heating of the battery 1 is stopped.

[0122] During the period from time t1 to time t2, compared with the charging rate of the battery 1 (dashed line) when the battery 1 was not pre-heated (before time t3), the charging rate of the battery 1 (solid line) decreases over time. Moreover, since the heating of the battery 1 is stopped at time t2, the charging rate of the battery 1 (solid line) and the charging rate of the battery 1 (dashed line) decrease while maintaining the same interval.

[0123] At time t3, if the vehicle 100 enters the regenerative braking driving path, the motor 4 starts supplying regenerative power to the battery 1 and increases the charging rate (SOC) of the battery 1. The temperature of the battery 1 (dashed line) is in a state lower than the lower limit temperature (T min ), and the allowable input (the part lower than T Figure 3 ) restricts the input to the battery 1. min ) restricts the input to the battery 1.

[0124] Therefore, the input (regenerative power) to the battery 1 is restricted by the allowable input shown in Figure 3 (the part lower than T min ) at time t4, and the charging rate of the battery 1 (dashed line) is lower than the charging rate of the battery 1 (solid line), and the difference expands over time.

[0125] At time t5, the temperature of the battery 1 (dashed line) rises to the lower limit temperature (T min) and the restriction on the input to the battery 1 is lifted. As a result, the charging rate of the battery 1 (dashed line) increases at the same rate as the charging rate of the battery 1 (solid line) thereafter, but does not exceed the charging rate of the battery 1 (solid line).

[0126] The magnitude of the regenerative braking force is equivalent to the magnitude of the input to the battery 1. During the period from time t4 to time t5, the magnitude of the regenerative braking force (input to the battery 1 (dashed line)) when the battery 1 is not heated in advance (before time t3) is lower than the regenerative braking force (input to the battery 1 (solid line)) when the battery 1 is heated in advance by the heater 26, and therefore, it is necessary to make up for the shortfall by, for example, friction braking force.

[0127] [4th Timing Diagram]

[0128] Figure 11 In the control system of the electric vehicle of the present embodiment, it is predicted that the temperature of the battery 1 will reach the upper limit temperature (T max ) is a timing diagram for a case where the battery 1 is cooled in advance.

[0129] At time t0, the vehicle 100 is traveling on a low-load driving route (or a high-load output driving route). In addition, the temperature of the battery 1 is the intermediate temperature (T mid ) and the lower limit temperature (T min ) between the temperatures.

[0130] At time t0, the EV controller 21 predicts the temperature change of the battery 1 and the input change in the following manner (1)-(3). (1) At time t2, the vehicle 100 enters the regenerative braking driving path and the input to the battery 1 increases, causing the temperature of the battery 1 (dashed line) to increase. (2) At time t3, the battery 1 is cooled by the cooler 25 (or the radiator 24) (dashed line), causing the temperature of the battery 1 to increase (dashed line). Figure 11 The slope of the line representing the temperature of the battery 1) decreases slightly. (3) The temperature of the battery 1 reaches the upper limit temperature (T4) at time t4. max ) and according to Figure 3 The allowable input (above T max The input to the battery 1 is limited, and the regenerative braking force is also limited accordingly.

[0131] Therefore, at time t1 , the EV controller 21 starts cooling of the battery 1 by the cooler 25 (or the radiator 24 ) (solid line).

[0132] At time t2, when the temperature of the battery 1 decreases to the lower limit temperature (T min) The timed vehicle 100 enters the regenerative braking driving path. At this time, the EV controller 21 continuously cools the battery 1 based on the cooler 25 (or radiator 24).

[0133] At time t5, if the temperature of the battery 1 reaches the upper limit temperature (T max ), then according to Figure 3 's allowable input (the part higher than T max ), the input of the battery 1 is restricted. However, since it is restricted after time t5 which is later than time t4, compared with the case where the temperature of the battery 1 was not cooled beforehand (before time t2) (dashed line), the regenerative braking force requested by the vehicle side on the regenerative braking driving path (the input of the battery 1 (solid line)) can be maintained for a longer time.

[0134] In addition, regarding the charging rate of the battery 1 (solid line) in the case where the battery 1 is cooled beforehand, power is supplied to the compressor that circulates the refrigerant in the cooler 25 after time t1, so it is lower than the charging rate of the battery 1 (dashed line) in the case where the battery 1 was not cooled beforehand.

[0135] However, the input of the battery 1 is restricted at time t4 in the case where the battery 1 was not cooled beforehand, so the charging rate (solid line) of the battery 1 is higher than the charging rate (dashed line) of the battery 1 between time t4 and time t5.

[0136] After time t5, the charging rate (solid line) of the battery 1 and the charging rate (dashed line) of the battery 1 change in the same way, but the difference between the charging rate (solid line) of the battery 1 and the charging rate (dashed line) of the battery 1 is maintained.

[0137] However, in the case where the battery 1 realizes the power required for cooling the battery 1, that is, the power of the compressor that supplies the refrigerant to the cooler 25, and if the charging rate of the battery 1 is higher than the specified upper limit value (S max : for example, 80 [%]), the allowable input [kW] of the battery 1 is restricted and the degradation protection of the battery 1 is performed. In the case where it is predicted that the charging rate (SOC) of the battery 1 will reach the upper limit value (S max ) during the driving of the vehicle 100 on the regenerative braking driving path, it is also preferable that the EV controller 21 executes the control to cool the battery 1 before the vehicle 100 enters the regenerative braking driving path.

[0138] In this case, for example, if the charging rate (SOC) of the battery 1 reaches the upper limit value at time t4 of Figure 11 , then as shown by the dashed line of "battery input / output" in Figure 11 , the input of the battery 1 thereafter is restricted.

[0139] However, for example, at time t1, cooling of the battery 1 using the cooler 25 is performed to reduce the state of charge (SOC) of the battery 1 before the vehicle 100 enters the regenerative braking driving path. Thus, for example Figure 11 as shown by the solid line of "battery input / output", the input to the battery 1 is not restricted until time t5.

[0140] Therefore, by pre-reducing the state of charge of the battery 1 before the vehicle 100 enters the regenerative braking driving path, it is possible to reduce the shortage of input to the battery 1 from time t4 to time t5, that is, the shortage of regenerative braking. Also, since the battery 1 is cooled before the vehicle 100 enters the regenerative braking driving path, it is possible to reduce the frequency at which the temperature of the battery 1 reaches the upper limit temperature (T max ) during the travel of the vehicle 100 on the regenerative braking driving path.

[0141] [5th Timing Diagram]

[0142] Figure 12 This is a timing diagram in the control system of the electric vehicle in the present embodiment when it is predicted that the vehicle 100 will reach a charging station and the battery 1 will be charged, and the battery 1 is pre-heated.

[0143] At time t0, the vehicle 100 travels on a low-load driving path (which can be a high-load output driving path or a regenerative braking driving path) at a specified output.

[0144] At time t0, the EV controller 21 predicts that the vehicle 100 will reach the charging station at time t3 and the output will become zero, but the temperature of the battery 1 at this time (dashed line) is lower than the lower limit temperature (T min ).

[0145] Therefore, the EV controller 21 starts heating the battery 1 at time t0.

[0146] At time t1, the temperature of the battery 1 (solid line) rises to the lower limit temperature (T min ), so the EV controller 21 stops heating the battery 1.

[0147] At time t2, the vehicle 100 reaches the charging station and starts charging the battery 1 (fast charging). As a result, the input to the battery 1 (solid line) and the temperature of the battery 1 (solid line) increase. Here, the temperature of the battery 1 is higher than the lower limit temperature (T min ), and the input to the battery 1 is not restricted, so the input to the battery 1 (solid line) requested by the vehicle side can be obtained.

[0148] On the other hand, in the case where the battery 1 is not pre-heated (before time t2), from time t0 to time t2, the temperature of the battery 1 (dashed line) becomes lower than the lower limit temperature (T min) state. Moreover, if the charging of battery 1 starts at time t2, the input to battery 1 increases, thereby causing the temperature of battery 1 (dashed line) to also start increasing. However, at time t3, according to Figure 3 the allowable input of battery 1 shown (the part below T min ), the input to battery 1 is restricted, so the input to battery 1 (dashed line) is restricted and lower than the input to battery 1 (solid line).

[0149] At time t4, the temperature of battery 1 (dashed line) reaches the lower limit temperature (T min ), so the restriction on the input to battery 1 is released. However, during the period from time t3 to time t4, the input to battery 1 is restricted and the input to battery 1 (dashed line) requested by the vehicle side cannot be obtained. Correspondingly, it can be seen that the charging time of battery 1 is extended.

[0150] [Timing Diagram 6]

[0151] Figure 13 is a timing diagram in the case where, in the control system of the electric vehicle of the present embodiment, it is predicted that the temperature of battery 1 will reach the set temperature (T1) during the charging of battery 1 and battery 1 is cooled in advance.

[0152] At time t0, the vehicle 100 travels on a low-load driving path (which can be a high-load output driving path or a regenerative braking driving path). In addition, the temperature of battery 1 becomes a temperature between the intermediate temperature (T mid ) and the lower limit temperature (T min ).

[0153] In addition, at t0, the EV controller 21 predicts the temperature change and input change of battery 1 in the following ways (1)-(3). (1) The charging of battery 1 starts at time t2 and the input to battery 1 increases, causing the temperature of battery 1 (dashed line) to increase. (2) At time t3, the cooling of battery 1 (dashed line) based on the cooler 25 (or radiator 24) starts, causing the rate of increase in the temperature of battery 1 ( Figure 13 the slope of the line representing the temperature of battery 1) to slightly decrease. (3) At time t4, the temperature of battery 1 reaches the set temperature (T1), and according to Figure 3 the allowable input shown (the part above T max (dashed line)), the input to battery 1 is restricted. Correspondingly, it is predicted that the charging of battery 1 will lag.

[0154] Therefore, at time t1, the EV controller 21 starts the cooling of battery 1 (solid line) using the cooler 25 (or radiator 24).

[0155] At time t2, when the temperature of battery 1 decreases to the lower limit temperature (Tmin ) starts charging Battery 1 at a scheduled time. At this time, the EV controller 21 continuously cools Battery 1 based on the cooler 25.

[0156] At time t5, if the temperature of Battery 1 reaches the set temperature (T1), the input to Battery 1 is Figure 3 restricted according to the allowable input (the part above T1 (dashed line)), but is restricted after time t5, which is later than time t4.

[0157] Therefore, the charging rate of Battery 1 (solid line) when Battery 1 is cooled in advance (before time t2) is lower than the charging rate of Battery 1 (dashed line) when Battery 1 is not cooled in advance at time t2.

[0158] However, during the period from time t4 to time t5, the increase in the charging rate of Battery 1 (dashed line) is suppressed compared to the charging rate of Battery 1, and the charging rate of Battery 1 (solid line) is higher than the charging rate of Battery 1 (dashed line halfway through.

[0159] After time t5, the charging rate of Battery 1 (solid line) and the charging rate of Battery 1 (dashed line) increase at the same speed, but the difference between the charging rate of Battery 1 (solid line) and the charging rate of Battery 1 (dashed line) is maintained.

[0160] Therefore, the charging rate of Battery 1 (solid line) when Battery 1 is cooled in advance (before time t2) reaches full charge at time t6, and the charging rate of Battery 1 (dashed line) when Battery 1 is not cooled in advance reaches full charge at time t7, which is later than time t6 (S1). Here, full charge means that the charging rate of Battery 1 reaches a specified charging rate or a specified time has elapsed since the start of charging.

[0161] [Second Control Flow]

[0162] Figure 14 It is a flowchart (S201 - S215) when Battery 1 is charged and then the vehicle travels in the control system of the electric vehicle in this embodiment.

[0163] Here, the temperature of Battery 1 is cooled to be greater than or equal to the first intermediate temperature, and then if the temperature of Battery 1 is less than or equal to the second intermediate temperature (T mid2) Then stop cooling. The battery 1 is cooled by the cooler 25 or the radiator 24. When the temperature of the outside air is lower than the threshold temperature, the battery 1 is cooled by the radiator 24. When the temperature of the outside air is greater than or equal to the threshold temperature, the cooler 25 is used for cooling. Additionally, the threshold temperature is set to be lower when the load of the battery 1 predicted based on the load trend (information on the driving route) is greater, and conversely, higher when the load of the battery 1 predicted based on the load trend (information on the driving route) is smaller. Here, the magnitude of the load is predicted based on, for example, traffic information (load trend) before a specified monitoring distance (e.g., 10 [km]) relative to the vehicle 100 or information on the slope of the road before the monitoring distance (load trend), etc. Moreover, the threshold temperature when the load of the battery 1 is a high load is lower than the second intermediate temperature (T mid2 ) and it is assumed that the threshold temperature when the load of the battery 1 is a low load is higher than the set temperature (T1).

[0164] In step S201, the battery controller 22 detects that the charger (charging plug) at the charging station is inserted into the insertion port for the charging plug configured in the vehicle 100 and starts charging the battery 1.

[0165] In step S202, the EV controller 21 determines whether the temperature of the battery 1 has risen and reached the intermediate temperature (T mid1 ). If YES, it proceeds to step S203. If NO, it proceeds to step S204.

[0166] In step S203, since the threshold temperature is in a state higher than the first intermediate temperature (T mid1 ), the EV controller 21 cools the battery 1 using the cooler 25.

[0167] In step S204, the EV controller 21 determines whether the temperature of the battery 1 has reached the set temperature (T1). If YES, it proceeds to step S205. If NO, it proceeds to step S206.

[0168] In step S205, the EV controller 21 (battery controller 22) restricts the input to the battery 1 so as not to exceed the set temperature (T1) of the battery 1.

[0169] In step S206, the EV controller 21 determines whether the charging of the battery 1 is complete, that is, whether the charging rate of the battery 1 has reached full charge. If YES, it proceeds to step S207. If NO, it remains in step S206.

[0170] In step S207, the EV controller 21 (battery controller 22) stops the input to the battery 1 and executes Figure 6Steps S101, S102, and S103 shown above.

[0171] In step S208, the EV controller 21 determines whether the vehicle 100 enters a low-load driving path after the charging station. If YES, it proceeds to step S209; if NO, it proceeds to step S213.

[0172] In step S209, the EV controller 21 determines whether the end point of the low-load driving path is the destination of the vehicle 100. If YES, it proceeds to step S210; if NO, it proceeds to step S215.

[0173] In step S210, the EV controller 21 changes the load of the battery 1 from a high-load state to a low-load state by making the vehicle 100 enter the low-load driving path, thereby setting the threshold temperature to a temperature corresponding to the low load (for example, a temperature higher than the set temperature (T1)). Moreover, since the threshold temperature is in a state higher than the set temperature (T mid1 ), the EV controller 21 switches the cooling of the battery 1 from being based on the cooler 25 to using the radiator 24 for the cooling of the battery 1.

[0174] In step S211, the EV controller 21 determines whether the temperature of the battery 1 is less than or equal to the second intermediate temperature (T mid2 ). If YES, it proceeds to step S212; if NO, it stays in step S211.

[0175] In step S212, the EV controller 21 stops the cooling of the battery 1 based on the radiator 24. In this case, the second valve is closed to stop the circulation of the refrigerant between the radiator 24 and the battery 1. In addition, the radiator 24 is driven until the entire system of the vehicle 100 stops.

[0176] In step S213, since the threshold temperature is in a state lower than the second intermediate temperature (T mid2 ), the EV controller 21 continuously cools the battery 1 using the cooler 25.

[0177] In step S214, the EV controller 21 determines whether the temperature of the battery 1 is less than or equal to the second intermediate temperature. If YES, it proceeds to step S215; if NO, it proceeds to step S214.

[0178] In step S215, the EV controller 21 stops the cooling of the battery 1 based on the cooler 25. In this case, the compressor of the cooler 25 is stopped.

[0179] In addition, in the above flowchart, the battery 1 is charged in S201 to S206, but the state of the vehicle 100 before step S208 is not particularly limited, and it can also be applied to the control of entering the low-load driving path after driving on the high-load output driving path or the regenerative braking driving path (step S208 - step S215).

[0180] [Seventh timing chart]

[0181] Figure 15 It is a timing chart when, in the control system of the electric vehicle of the present embodiment, after the battery 1 is charged, the vehicle 100 drives on the low-load driving path and reaches the destination.

[0182] Before time t0, the temperature of the battery 1 is, for example, the initial temperature close to the outside air temperature (T0: a temperature lower than the second intermediate temperature (T mid2 ), and the charge rate of the battery 1 is the initial value (a value lower than the charge rate when fully charged), and the vehicle 100 stops at the charging station.

[0183] At time t0, if the EV controller 21 (battery controller 22) starts charging the battery 1, the input to the battery 1, the temperature of the battery 1, and the charge rate (SOC) of the battery 1 increase.

[0184] At time t1, the EV controller 21 sets the threshold temperature to a value lower than the second intermediate temperature (T mid2 ), so if the temperature of the battery 1 reaches the first intermediate temperature (T mid1 ), the cooling of the battery 1 based on the cooler 25 starts.

[0185] At time t2, if the temperature of the battery 1 reaches the set temperature (T1), the EV controller 21 (battery controller 22) restricts the input to the battery 1.

[0186] During the period from time t0 to time t3, the EV controller 21 predicts, based on information such as the driving path, whether the vehicle 100 will drive on the low-load driving path and its end point is the destination after the battery 1 is charged, before time t0 (before charging) and after time t3 until just after the vehicle 100 drives (just after charging).

[0187] At time t3, if the charging rate of battery 1 reaches full charge, the EV controller 21 (battery controller 22) stops the input to battery 1 and completes the charging. At this time, when the vehicle 100 is traveling on a low-load driving path, the threshold temperature is set to a temperature higher than the set temperature (T1), so the cooling of battery 1 based on the cooler 25 is stopped, and the cooling of battery 1 based on the radiator 24 is switched to. And, when the end point of the low-load driving path is the destination, the cooling of battery 1 based on the cooler 25 and the cooling of battery 1 based on the radiator 24 are not performed. In this case, the temperature of battery 1 (solid line) monotonically decreases until the initial temperature (T0) after time t3.

[0188] When the end point of the low-load driving path is not the destination, battery 1 is cooled by the radiator 24, and the temperature of battery 1 (dashed line) decreases at a faster rate than the temperature of battery 1 (solid line).

[0189] If the temperature of battery 1 reaches the second intermediate temperature (T mid2 ) at time t4, the cooling of battery 1 based on the radiator 24 is stopped, and then it monotonically decreases until the initial temperature (T0).

[0190] In addition, after time t3, when the vehicle 100 is traveling on a high-load output driving path, the cooling of battery 1 using the cooler 25 is continuously performed even after time t3, but if the temperature of battery 1 is less than or equal to the second intermediate temperature (T mid2 ), the cooling of battery 1 based on the cooler 25 is stopped.

[0191] Therefore, when the power of the compressor of the cooler 25 is realized for battery 1, during the period from time t3 to time t4, regarding the charging rate of battery 1 (dashed line), corresponding to the power supply to the compressor, the reduction amount is more than the charging rate of battery 1 (dashed line) when the compressor is stopped at time t3.

[0192] The compressor stops at time t4, so the charging rate of battery 1 (dashed line) decreases in the same way as the charging rate of battery 1 (solid line), but the charging rate of battery 1 (dashed line) will not be higher than the charging rate of battery 1 (solid line).

[0193] As described above, when it is predicted that the vehicle after charging battery 1 will travel on a low-load driving path, when the charging of battery 1 is completed, the cooling of battery 1 based on the cooler 25 is stopped, thereby reducing the power consumption of battery 1.

[0194] The above timing chart illustrates the case where the vehicle 100 travels on a low-load driving path after the battery 1 is charged, and the end point of the low-load driving path is the destination of the vehicle 100. However, it can also be applied as the temperature control of the battery 1 when the vehicle 100 enters a low-load driving path (at time t3) after traveling on a high-load output driving path or a regenerative braking driving path, and the end point of the low-load driving path is the destination of the vehicle 100.

[0195] [Effects of the present embodiment]

[0196] According to the control method of the electric vehicle of the present embodiment, power is supplied and received between the drive motor (motor 4) and the battery 1, and when the temperature of the battery 1 reaches a specified upper limit temperature (T max ) or is lower than a lower limit temperature (T max ) lower than the upper limit temperature (T min ), the charge and discharge power of the battery 1 is restricted. Among them, according to the driving path from the current location of the vehicle 100 to the destination, at least a low-load driving path on which the vehicle 100 travels in a state of low load relative to the battery 1 and a high-load driving path on which the vehicle 100 travels in a state of high load greater than the low load are estimated, a load transition indicating the change in the load of the battery 1 when the vehicle 100 travels on the driving path is calculated, the temperature transition of the battery 1 is calculated based on the load transition and the current temperature of the battery 1, and when it is predicted that the temperature of the battery 1 is lower than the lower limit temperature (T min ) when the load changes from the low-load state to the high-load state, the battery 1 is heated before the load becomes the high-load state, and when it is predicted that the temperature of the battery 1 reaches the upper limit temperature when the load is in the high-load state, the battery 1 is cooled before the load becomes the high-load state.

[0197] According to the above method, heating the battery 1 before the load of the battery 1 enters the high-load state can reduce the input / output shortage of the battery 1 when the load of the battery 1 changes from the low-load state to the high-load state in a state where the temperature of the battery 1 is lower than the lower limit temperature (T min ), and cooling the battery 1 before the load of the battery 1 enters the high-load state can reduce the input / output shortage of the battery 1 caused by the temperature of the battery 1 reaching the upper limit temperature (T max ) when the battery 1 is in the high-load state. Therefore, the input / output shortage when a high load is requested from the battery 1 can be reduced.

[0198] In the present embodiment, when it is predicted that the temperature of the battery 1 is lower than the lower limit temperature (T min) and when the load of the battery 1 does not enter a high-load state thereafter, the battery 1 is not heated, and when it is predicted that the temperature of the battery 1 is higher than the lower limit temperature (T min ) and when the load of the battery 1 does not enter a high-load state thereafter, the battery 1 is not cooled.

[0199] According to the above method, even when restricting the input and output of the battery 1 when the load of the battery 1 is in a high-load state, there is no need to heat or cool the battery 1 when the load of the battery 1 is not a high load, so the power consumption can be reduced accordingly.

[0200] In the present embodiment, the past low-load driving path and high-load driving path calculated using the map information representing the driving path from the current location of the vehicle 100 to the destination and the past map information with the same driving path are extracted as the current low-load driving path and high-load driving path.

[0201] According to the above method, the processing burden (of the EV controller 21) can be reduced and the low-load driving path and high-load driving path can be estimated in a simple manner.

[0202] In the present embodiment, the high-load driving path includes a high-load output driving path in which the battery 1 supplies power to the drive motor (motor 4), and the low-load driving path and the high-load output driving path are estimated based on the map information representing the driving path from the current location of the vehicle 100 to the destination.

[0203] According to the above method, when it is known that the road state from the departure location to the destination of the vehicle 100 is monotonous, the low-load driving path and the high-load output driving path can be estimated simply without using the map information.

[0204] In the present embodiment, the map information includes information on the positions of the roads constituting the driving path, information on the slopes of the roads, and information on the predicted vehicle speeds of the roads. In the map information, the parts of the uphill-slope roads with a distance greater than or equal to a specified distance and the parts with a predicted vehicle speed greater than or equal to a specified speed are presumed to be high-load output driving paths.

[0205] According to the above method, the high-load output driving path can be estimated with high accuracy based on the map information.

[0206] In the present embodiment, the high-load driving path includes a high-load output driving path in which the battery 1 supplies power to the drive motor (motor 4), and the low-load driving path and the high-load output driving path are estimated based on the load at the current location or the load from the departure location of the vehicle 100 to the current location.

[0207] According to the above method, when the road conditions from the departure location to the destination of the vehicle 100 are monotonous, it is possible to simply estimate the low-load driving path and the high-load output driving path without using map information.

[0208] In the present embodiment, the high-load driving path includes a regenerative braking driving path in which the drive motor (motor 4) supplies regenerative power to the battery 1 and brakes the vehicle 100. When the temperature of the battery 1 when the vehicle 100 enters the regenerative braking driving path is lower than the lower limit temperature (T min ), the battery 1 is heated before the vehicle 100 enters the regenerative braking driving path. When it is predicted that the temperature of the battery 1 will reach the upper limit temperature (T max ) during the driving of the vehicle 100 on the regenerative braking driving path, the battery 1 is cooled before the vehicle 100 enters the regenerative braking driving path.

[0209] According to the above method, heating the battery 1 before the vehicle 100 enters the regenerative braking driving path can reduce the input shortage of the battery 1 when the vehicle 100 enters the regenerative braking driving path in a state where the temperature of the battery 1 is lower than the lower limit temperature (T min ), and cooling the battery 1 before the vehicle 100 enters the regenerative braking driving path can reduce the input shortage of the battery 1 caused by the temperature of the battery 1 reaching the upper limit temperature (T max ) during the driving of the vehicle 100 on the regenerative braking driving path. Therefore, it is possible to reduce the input shortage when requesting regenerative power input to the battery 1.

[0210] In the present embodiment, the regenerative braking driving path is estimated based on the map information indicating the driving path from the current location of the vehicle 100 to the destination. The map information includes information on the position of the road constituting the driving path, information on the slope of the road, and information on the predicted vehicle speed of the road. In the map information, a portion where the downhill slope road continues for a distance greater than or equal to a specified distance or a portion where the predicted vehicle speed enters a region where it decreases by a speed difference greater than or equal to a specified speed is estimated as the regenerative braking driving path.

[0211] According to the above method, it is possible to accurately estimate the regenerative braking driving path using map information.

[0212] In the present embodiment, when the temperature of the battery 1 before the vehicle 100 enters the regenerative braking driving path is lower than the lower limit temperature (T min ), when it is predicted that the total amount of power (total battery heating power) required to heat the temperature of the battery 1 to the lower limit temperature (T min ) is higher than that from when heating the temperature of the battery 1 to the lower limit temperature (T min)When the difference (total increase in regenerative power) obtained by subtracting the total amount of regenerative power obtained when the vehicle 100 travels on the regenerative braking travel path after that from the total amount of regenerative power obtained when the vehicle 100 travels on the regenerative braking travel path without performing heating of the battery 1 before the vehicle 100 enters the regenerative braking travel path, heating of the battery 1 before the vehicle 100 enters the regenerative braking travel path is not performed. When the temperature of the battery 1 before the vehicle 100 enters the regenerative braking travel path is higher than the lower limit temperature (T min ), when it is predicted that the total amount of power (total battery cooling power) required to cool the temperature of the battery 1 to the lower limit temperature (T min ) is higher than the difference (total increase in regenerative power) obtained by subtracting the total amount of regenerative power obtained when the vehicle 100 travels on the regenerative braking travel path after cooling the temperature of the battery 1 to the lower limit temperature (T min ) from the total amount of regenerative power obtained when the vehicle 100 travels on the regenerative braking travel path without performing cooling of the battery 1 before the vehicle 100 enters the regenerative braking travel path, cooling of the battery before the vehicle enters the regenerative braking travel path is not performed.

[0213] According to the above method, it is possible to avoid a state where the charging rate of the battery 1 after the vehicle 100 passes through the regenerative braking travel path is lower than the charging rate of the battery 1 before the vehicle 100 enters the regenerative braking travel path.

[0214] In the present embodiment, in the case where if the battery 1 achieves the power required for cooling the battery 1 and the charging rate (SOC) of the battery 1 reaches a specified upper limit value (S max ), the charging power (input) of the battery 1 is restricted, when it is predicted that the charging rate (SOC) of the battery 1 reaches the upper limit value (S max ) during the travel of the vehicle 100 on the regenerative braking travel path, the battery 1 is cooled before the vehicle 100 enters the regenerative braking travel path.

[0215] According to the above method, in order to supply power for cooling the battery 1 before the vehicle 100 enters the regenerative braking travel path, the battery 1 is discharged, thereby reducing the shortage of input to the battery 1, that is, the shortage of regenerative braking force. And, since the battery 1 is cooled before the vehicle 100 enters the regenerative braking travel path, it is possible to reduce the frequency at which the temperature of the battery 1 reaches the upper limit temperature (T max ) during the travel of the vehicle 100 on the regenerative braking travel path.

[0216] In the present embodiment, heating and cooling of the battery 1 can be performed when the charging rate of the battery 1 is greater than or equal to a specified lower limit value (S min ), and heating and cooling of the battery 1 cannot be performed when the charging rate is lower than the lower limit value (S min) the heating and cooling of the battery 1 cannot be performed.

[0217] According to the above method, it is possible to prevent the depletion of the battery 1 during the running of the vehicle 100.

[0218] In the present embodiment, it is further presumed that there is a charging station on the driving route where the battery 1 can be charged. When it is predicted that the temperature of the battery 1 is lower than the lower limit temperature (T min ) when the vehicle 100 arrives at the charging station and charges the battery 1, the battery 1 is heated before the vehicle 100 arrives at the charging station. When it is predicted that the temperature of the battery 1 reaches the upper limit temperature (T max , set temperature (T1)) during the charging of the battery 1 at the charging station, the battery 1 is cooled before the vehicle 100 arrives at the charging station.

[0219] According to the above method, heating the battery 1 before the vehicle 100 arrives at the charging station can reduce the input / output shortage of the battery 1 when starting to charge the battery 1 in a state where the temperature of the battery 1 is lower than the lower limit temperature (T min ). Cooling the battery 1 before the vehicle 100 arrives at the charging station can reduce the input / output shortage of the battery 1 caused by the temperature of the battery 1 reaching the upper limit temperature (T max , set temperature (T1)) during the charging of the battery 1. Therefore, it is possible to reduce the input shortage when requesting charging power for the battery 1 and shorten the charging time.

[0220] In the present embodiment, the low-load driving route and the charging station are presumed based on the map information indicating the driving route from the current location of the vehicle 100 to the destination.

[0221] According to the above method, the low-load driving route and the charging station can be reliably extracted based on the map information.

[0222] In the present embodiment, if the temperature of the battery 1 is greater than or equal to the intermediate temperature (T max , set temperature (T1)) between the upper limit temperature (T min ) and the lower limit temperature (T mid , first intermediate temperature (T mid1 ))), the battery 1 is cooled. If the temperature of the battery 1 is lower than the intermediate temperature (T mid , second intermediate temperature (T mid2 ))), the cooling of the battery 1 is stopped. In this case, when it is predicted that the vehicle 100 starts to run on the low-load driving route in a state where the temperature of the battery 1 is higher than the intermediate temperature (T mid , second intermediate temperature (T mid2 )) and the end point of the low-load driving route is the destination, the cooling of the battery 1 is stopped.

[0223] According to the above method, it is determined that there is no sharp temperature rise again, and the cooling of battery 1 is stopped. Therefore, compared with the case where the cooling of battery 1 is stopped when the temperature is lower than the specified intermediate temperature (T mid , the second intermediate temperature (T mid2 ), power consumption can be reduced.

[0224] In the present embodiment, when the cooler 25 and the radiator 24 capable of cooling battery 1 are mounted on the vehicle 100, when the temperature of the outside air is greater than or equal to the specified threshold temperature, battery 1 is cooled by the cooler 25, and when the temperature of the outside air is lower than the threshold temperature, battery 1 is cooled by the radiator 24. It is set that the higher the load predicted according to the load trend, the lower the threshold temperature, and the lower the load predicted according to the load trend, the higher the threshold temperature.

[0225] The power consumption of the compressor (not shown) of the cooler 25 is higher than that of the circulation pump (not shown) that circulates the refrigerant in the radiator 24. Therefore, according to the above method, the radiator 24 can preferentially perform the cooling of battery 1 compared with the cooler 25 when the load is low, so that the power consumption of the entire system can be reduced.

[0226] The control system of the electric vehicle according to the present embodiment includes: a drive motor (motor 4); a battery 1 that supplies and receives power to and from the drive motor (motor 4); and a control unit (EV controller 21) that, when the temperature of the battery 1 reaches the specified upper limit temperature (T max ) or the temperature of the battery 1 is lower than the specified lower limit temperature (T max ) that is lower than the upper limit temperature (T min ), restricts the charge and discharge power of the battery 1. The control unit (EV controller 21) calculates at least the low-load driving path on which the vehicle 100 travels in a state of low load on the battery 1 and the high-load driving path on which the vehicle 100 travels in a state of high load greater than the low load based on the driving path from the current location of the vehicle 100 to the destination, thereby calculating the load trend representing the change in the load of the battery 1 when the vehicle 100 travels on the driving path, calculating the temperature trend of the battery 1 based on the load trend and the current temperature of the battery 1, and predicting that when the load changes from the low-load state to the high-load state, if the temperature of the battery 1 is lower than the lower limit temperature (T min ), heating the battery 1 before the load becomes the high-load state, and predicting that when the load is in the high-load state, if the temperature of the battery 1 reaches the upper limit temperature (T max ), cooling the battery 1 before the load becomes the high-load state.

[0227] According to the above structure, heating the battery 1 before the load of the battery 1 enters the high load state can reduce the input / output shortage of the battery 1 when the load of the battery 1 changes from the low load state to the high load state while the temperature of the battery 1 is lower than the lower limit temperature (T min ). Cooling the battery 1 before the load of the battery 1 enters the high load state can reduce the input / output shortage of the battery 1 caused by the temperature of the battery 1 reaching the upper limit temperature (T max ) when the battery 1 is in the high load state. Therefore, the input / output shortage when a high load is requested for the battery 1 can be reduced.

[0228] The embodiments of the present invention have been described above, but the above embodiments merely represent a part of the application examples of the present invention, and the gist thereof is not to limit the technical scope of the present invention to the specific structures of the above embodiments. In addition, the above embodiments can be combined appropriately.

Claims

1. A control method for an electric vehicle that supplies and receives electric power between a drive motor and a battery, and restricts the charge and discharge power of the battery when the temperature of the battery reaches a specified upper limit temperature or is lower than a lower limit temperature that is lower than the upper limit temperature, wherein, Based on the driving route from the current location of the vehicle to the destination, at least estimate a low-load driving route on which the vehicle travels in a state where the load on the battery is a low load and a high-load driving route on which the vehicle travels in a state where the load is a high load greater than the low load, thereby calculating a load progression that represents the change in the load on the battery when the vehicle travels on the driving route. Calculate the temperature progression of the battery based on the load progression and the current temperature of the battery. When it is predicted that the temperature of the battery will be lower than the lower limit temperature when the load changes from the low-load state to the high-load state, heat the battery before the load becomes the high-load state. When it is predicted that the temperature of the battery will reach the upper limit temperature when the load is in the high-load state, cool the battery before the load becomes the high-load state.

2. The control method for an electric vehicle according to claim 1, wherein, When it is predicted that the temperature of the battery is lower than the lower limit temperature and the load on the battery does not enter the high-load state thereafter, do not heat the battery. When it is predicted that the temperature of the battery is higher than the lower limit temperature and the load on the battery does not enter the high-load state thereafter, do not cool the battery.

3. The control method for an electric vehicle according to claim 1, wherein, As the current low-load driving route and high-load driving route, extract the past low-load driving route and high-load driving route calculated using map information representing the driving route from the current location of the vehicle to the destination and the same past map information as the driving route.

4. The control method for an electric vehicle according to claim 1, wherein, The high-load driving route includes a high-load output driving route in which the battery supplies power to the drive motor. Based on the map information representing the driving route from the current location of the vehicle to the destination, estimate the low-load driving route and the high-load output driving route.

5. The control method for an electric vehicle according to claim 4, wherein, The map information includes information on the positions of the roads constituting the driving route, information on the gradients of the roads, and information on the predicted vehicle speeds on the roads. In the map information, a portion where the road with an uphill gradient continues for a distance greater than or equal to a specified distance and a portion where the predicted vehicle speed is greater than or equal to a specified speed are presumed to be the high-load output driving route.

6. The control method for an electric vehicle according to claim 1, wherein, The high-load driving path includes a high-load output driving path in which the battery supplies power to the drive motor. The low-load driving path and the high-load output driving path are estimated based on the load at the current location or the load from the departure location of the vehicle to the current location.

7. The control method for an electric vehicle according to claim 1, wherein The high-load driving path includes a regenerative braking driving path in which the drive motor supplies regenerative power to the battery and brakes the vehicle. When the temperature of the battery when the vehicle enters the regenerative braking driving path is lower than the lower limit temperature, the battery is heated before the vehicle enters the regenerative braking driving path. When it is predicted that the temperature of the battery will reach the upper limit temperature during the vehicle's travel on the regenerative braking driving path, the battery is cooled before the vehicle enters the regenerative braking driving path.

8. The control method for an electric vehicle according to claim 7, wherein The regenerative braking driving path is estimated based on the map information indicating the driving path from the current location of the vehicle to the destination. The map information includes information on the positions of the roads constituting the driving path, information on the gradients of the roads, and information on the predicted vehicle speeds of the roads. In the map information, a portion of the road with a downhill gradient that continues for a distance greater than or equal to a specified distance or a portion that enters a region with a lower speed from a region with a higher predicted vehicle speed by a speed difference greater than or equal to a specified value is presumed to be the regenerative braking driving path.

9. The control method for an electric vehicle according to claim 7, wherein When the temperature of the battery before the vehicle enters the regenerative braking driving path is lower than the lower limit temperature, if the total amount of power required to heat the battery to the lower limit temperature is higher than the difference obtained by subtracting the total amount of regenerative power obtained when the vehicle travels on the regenerative braking driving path after heating the battery to the lower limit temperature from the total amount of regenerative power obtained when the vehicle travels on the regenerative braking driving path without performing the heating of the battery before the vehicle enters the regenerative braking driving path, the heating of the battery before the vehicle enters the regenerative braking driving path is not performed. When the temperature of the battery before the vehicle enters the regenerative braking driving path is higher than the lower limit temperature, and the total amount of power predicted to cool the battery to the lower limit temperature is higher than the difference obtained by subtracting the total amount of regenerative power obtained when the vehicle travels on the regenerative braking driving path after cooling the battery to the lower limit temperature from the total amount of regenerative power obtained when the vehicle travels on the regenerative braking driving path without performing cooling of the battery before the vehicle enters the regenerative braking driving path, cooling of the battery before the vehicle enters the regenerative braking driving path is not performed.

10. The control method for an electric vehicle according to claim 7, wherein when the power required for the battery to achieve cooling of the battery and the charging rate of the battery reach a specified upper limit value, the charging power of the battery is restricted, when it is predicted that the charging rate of the battery reaches the upper limit value during the vehicle traveling on the regenerative braking driving path, the battery is cooled before the vehicle enters the regenerative braking driving path.

11. The control method for an electric vehicle according to claim 1, wherein when the charging rate of the battery is greater than or equal to a specified lower limit value, heating and cooling of the battery can be performed, when the charging rate is lower than the lower limit value, heating and cooling of the battery cannot be performed.

12. The control method for an electric vehicle according to claim 1, wherein a charging station where the battery can be charged on the driving path is further estimated, when it is predicted that the temperature of the battery is lower than the lower limit temperature when the battery is charged when the vehicle arrives at the charging station, the battery is heated before the vehicle arrives at the charging station, when it is predicted that the temperature of the battery reaches the upper limit temperature during charging of the battery at the charging station, the battery is cooled before the vehicle arrives at the charging station.

13. The control method for an electric vehicle according to claim 12, wherein the charging station is estimated based on map information indicating the driving path from the current location of the vehicle to the destination.

14. The control method for an electric vehicle according to claim 1, wherein when the battery is cooled so that the temperature of the battery is greater than or equal to the intermediate temperature between the upper limit temperature and the lower limit temperature and the cooling of the battery is stopped if the temperature of the battery is lower than the intermediate temperature, when it is predicted that the vehicle starts traveling on the low-load driving path in a state where the temperature of the battery is higher than the intermediate temperature and the end point of the low-load driving path is the destination, the cooling of the battery is stopped.

15. The control method for an electric vehicle according to claim 1, wherein when a cooler and a radiator capable of cooling the battery are mounted on the vehicle, When the temperature of the external air is greater than or equal to a specified threshold temperature, the battery is cooled using the cooler, and when the temperature of the external air is lower than the threshold temperature, the battery is cooled using the radiator. It is set that the higher the load predicted according to the load trend, the lower the threshold temperature, and the lower the load predicted according to the load trend, the higher the threshold temperature.

16. A control system for an electric vehicle, the electric vehicle comprising: A drive motor; A battery that supplies and receives power to and from the drive motor; and A control unit that restricts the charge / discharge power of the battery when the temperature of the battery reaches a specified upper limit temperature or when the temperature of the battery is lower than a specified lower limit temperature that is lower than the upper limit temperature, wherein The control unit calculates a load trend representing a change in the load on the battery when the vehicle travels on the travel path by at least estimating a low-load travel path on which the vehicle travels in a state where the load on the battery is a low load and a high-load travel path on which the vehicle travels in a state where the load is a high load greater than the low load, based on the travel path from the current location of the vehicle to the destination. Based on the load trend and the current temperature of the battery, the temperature trend of the battery is calculated. When it is predicted that the temperature of the battery will be lower than the lower limit temperature when the load changes from the low-load state to the high-load state, the battery is heated before the load becomes the high-load state. When it is predicted that the temperature of the battery will reach the upper limit temperature when the load is in the high-load state, the battery is cooled before the load becomes the high-load state.

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