JP2018075990A - Device for controlling electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate inhibiting a failure to thoroughly recover regenerative electric power due to rise of temperature in executing down SOC control in a power storage device, in an electric vehicle configured so as to be capable of executing down SOC control.SOLUTION: A vehicle includes: a power storage device; a second MG (motor generator) driven with electrical power from the power storage device; a cooling fan for cooling the power storage device; and HV-ECU configured so as to be capable of executing down SOC control. The HV-ECU enhances performance of the cooling fan to cool the power storage device, compared with that when down SOC control is not executed.SELECTED DRAWING: Figure 6

Description

  The present disclosure relates to a control device for an electric vehicle including a traveling motor driven by electric power of a power storage device.

  Conventionally, development of a control for supporting energy saving operation of an electric vehicle by a user has been advanced. As one of them, for example, Japanese Patent Laying-Open No. 2011-6047 (Patent Document 1) discloses an electric vehicle configured to be able to execute “down SOC control” (SOC: State Of Charge). The “downhill SOC control” is an electric vehicle equipped with a traveling motor driven by electric power of the power storage device, and when there is a target downlink section that satisfies the downlink extraction condition on the planned travel route of the electric vehicle, In this control, the SOC of the power storage device is reduced in advance by consuming a larger amount of power from the power storage device than before entering normal time (when the downward SOC control is not executed).

  While traveling in the target downward section, the SOC increases due to the regenerative power of the motor, but since the SOC is reduced in advance before entering the target downstream section by the downward SOC control, the regenerative power during traveling in the target downstream section The amount of recovery can be increased.

JP 2011-6047 A JP 2006-306231 A

  When the above-described downward SOC control is executed, due to the temperature rise of the power storage device, regenerative power is lost during traveling or after passing the target downward section (a part of the kinetic energy of the vehicle is transferred to the power storage device as regenerative power). There is a concern that a situation may occur in which it is not recovered but is converted into heat by the operation of a friction brake and discarded.

  Specifically, as described above, the downlink SOC control is a control that increases the amount of recovered regenerative power in the target downlink section by consuming a large amount of power from the power storage device before entering the target downlink section. is there. Therefore, when the downward SOC control is executed, the continuous charging time in the target downward section becomes longer than normal time (when the downward SOC control is not executed), and the temperature of the power storage device may be higher than normal time. There is sex. In general, when the temperature of the power storage device exceeds the limit threshold, the acceptable power (unit: watts) of the power storage device is greater than the normal value (value when the temperature of the power storage device is less than the limit threshold). However, when the temperature of the power storage device exceeds the limit threshold during traveling or after passing through the target down section due to execution of the downward SOC control, the receivable power of the power storage device is smaller than the normal value. There is a concern that regenerative power may be overlooked.

  The present disclosure has been made in order to solve the above-described problem, and the object thereof is caused by an increase in the temperature of the power storage device due to the execution of the downward SOC control in the electric vehicle configured to be able to execute the downward SOC control. This is to make it easy to suppress the loss of regenerative power.

  A control device according to the present disclosure is a control device for an electric vehicle including a traveling motor that is driven by electric power of a power storage device. This control device reduces in advance the amount of power stored in the power storage device before entering the target down section when there is a target down section on the planned traveling route of the electric vehicle and the cooling unit configured to cool the power storage device And a control unit configured to be able to execute downlink SOC control. The control unit increases the operation amount of the cooling unit when the downward SOC control is being executed, compared to the case where the downward SOC control is not being executed.

  According to the above configuration, when the downward SOC control is executed, the operation amount of the cooling unit is increased. Thereby, since the cooling capability of the power storage device by the cooling unit is strengthened, it is possible to further suppress the temperature rise of the power storage device. Therefore, it is difficult to limit the power that can be received by the power storage device during traveling or after passing through the target downhill section. As a result, it is possible to easily suppress the loss of regenerative power due to the temperature rise of the power storage device due to the execution of the downward SOC control.

1 is an overall configuration diagram of a vehicle. It is a block diagram which shows the detailed structure of HV-ECU, various sensors, and a navigation apparatus. It is a flowchart which shows an example of the process sequence of traveling control. It is the figure which showed an example of the calculation method of charging / discharging request | requirement power Pb. It is a figure for demonstrating downlink SOC control. It is a flowchart which shows an example of the process sequence of downlink SOC control.

  Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

  FIG. 1 is an overall configuration diagram of a vehicle 1 according to the present embodiment. The vehicle 1 includes an engine 10, a first motor generator (hereinafter referred to as “first MG”) 20, a second motor generator (hereinafter referred to as “second MG”) 30, a power split device 40, and a PCU ( Power Control Unit) 50, power storage device 60, and drive wheel 80.

  The vehicle 1 is a hybrid vehicle that travels by at least one of the power of the engine 10 and the power of the second MG 30. Note that, in the present disclosure, the case where the vehicle 1 is a hybrid vehicle will be representatively described. However, a vehicle to which the present disclosure can be applied may be an electric vehicle including a motor generator for traveling. It is not limited.

  The engine 10 is an internal combustion engine that outputs power by converting combustion energy generated when an air-fuel mixture is burned into kinetic energy of a moving element such as a piston or a rotor. Power split device 40 includes, for example, a planetary gear mechanism having three rotation shafts of a sun gear, a carrier, and a ring gear. Power split device 40 splits the power output from engine 10 into power for driving first MG 20 and power for driving drive wheels 80.

  First MG 20 and second MG 30 are AC rotating electric machines, for example, three-phase AC synchronous motors in which a permanent magnet is embedded in a rotor. The first MG 20 is mainly used as a generator driven by the engine 10 via the power split device 40. The electric power generated by first MG 20 is supplied to second MG 30 or power storage device 60 via PCU 50.

  Second MG 30 mainly operates as an electric motor and drives drive wheels 80. Second MG 30 is driven by receiving at least one of the electric power from power storage device 60 and the generated electric power of first MG 20, and the driving force of second MG 30 is transmitted to driving wheels 80. On the other hand, the second MG 30 operates as a generator to perform regenerative power generation when braking the vehicle 1 or reducing acceleration on a downhill. The electric power generated by second MG 30 is collected by power storage device 60 via PCU 50.

  PCU 50 converts the DC power received from power storage device 60 into AC power for driving first MG 20 and second MG 30. PCU 50 converts AC power generated by first MG 20 and second MG 30 into DC power for charging power storage device 60. PCU 50 includes, for example, two inverters provided corresponding to first MG 20 and second MG 30, and a converter that boosts a DC voltage supplied to each inverter to a voltage higher than that of power storage device 60.

  Power storage device 60 is a rechargeable DC power source, and includes a secondary battery such as a lithium ion battery or a nickel metal hydride battery. Power storage device 60 is charged by receiving power generated by at least one of first MG 20 and second MG 30. Then, power storage device 60 supplies the stored power to PCU 50. An electric double layer capacitor or the like can also be used as the power storage device 60.

  The power storage device 60 is provided with a monitoring unit 61. Monitoring unit 61 includes a voltage sensor, a current sensor, and a temperature sensor (none of which are shown) for detecting the voltage, input / output current, and temperature of power storage device 60, respectively. Monitoring unit 61 outputs detection values (voltage, input / output current and temperature of power storage device 60) of each sensor to BAT-ECU 110.

  The power storage device 60 is provided with a cooling fan 62. Cooling fan 62 operates in response to a control signal from HV-ECU 100 and supplies cooling air to power storage device 60. The operating amount of the cooling fan 62 (the cooling capacity of the power storage device 60 by the cooling fan 62) is adjusted by the HV-ECU 100.

  The vehicle 1 further includes an HV-ECU (Electronic Control Unit) 100, a BAT-ECU 110, various sensors 120, a navigation device 130, and an HMI (Human Machine Interface) device 140.

  FIG. 2 is a block diagram showing a detailed configuration of HV-ECU 100, various sensors 120, and navigation device 130 shown in FIG. The HV-ECU 100, the BAT-ECU 110, the navigation device 130, and the HMI device 140 are configured to be able to communicate with each other through a CAN (Controller Area Network) 150.

  The various sensors 120 include, for example, an accelerator pedal sensor 122, a vehicle speed sensor 124, and a brake pedal sensor 126. The accelerator pedal sensor 122 detects an accelerator pedal operation amount (hereinafter also referred to as “accelerator opening”) ACC by the user. The vehicle speed sensor 124 detects the vehicle speed VS of the vehicle 1. The brake pedal sensor 126 detects a brake pedal operation amount BP by the user. Each of these sensors outputs a detection result to HV-ECU 100.

  The HV-ECU 100 includes a CPU (Central Processing Unit), a ROM (Read Only Memory) that stores processing programs, a RAM (Random Access Memory) that temporarily stores data, and an input / output port for inputting and outputting various signals. (Not shown) and the like, and predetermined arithmetic processing is executed based on information stored in a memory (ROM and RAM), information from various sensors 120, and information from the BAT-ECU 110. And HV-ECU100 controls each apparatus, such as the engine 10, PCU50, the HMI apparatus 140, and the cooling fan 62, based on the result of a calculation process.

  The BAT-ECU 110 also includes a CPU, a ROM, a RAM, an input / output port, and the like (all not shown), and the power storage device 60 is based on the input / output current and / or voltage detection values of the power storage device 60 from the monitoring unit 61. The SOC is calculated. The SOC is expressed, for example, as a percentage of the current storage amount with respect to the full charge capacity of the storage device 60. Then, BAT-ECU 110 outputs the calculated SOC to HV-ECU 100. Note that the HV-ECU 100 may calculate the SOC.

  Further, BAT-ECU 110 outputs the detected value of temperature of power storage device 60 by monitoring unit 61 to HV-ECU 100.

  HV-ECU 100 sets acceptable power WIN (unit: watts) of power storage device 60 based on the SOC and temperature of power storage device 60 received from BAT-ECU 110. For example, HV-ECU 100 sets acceptable power WIN to a smaller value as the SOC increases. Further, when the temperature of power storage device 60 exceeds the limit threshold value, HV-ECU 100 sets the acceptable power WIN of power storage device 60 to a normal value (when the temperature of power storage device 60 is lower than the limit threshold value). Value). HV-ECU 100 controls the power generated by first MG 20 and second MG 30 so that the power input to power storage device 60 does not exceed acceptable power WIN.

  When the temperature of power storage device 60 received from BAT-ECU 110 exceeds a predetermined temperature, HV-ECU 100 cools power storage device 60 by operating cooling fan 62 and supplying cooling air to power storage device 60. When operating the cooling fan 62, the HV-ECU 100 can adjust the cooling capacity of the power storage device 60 by the cooling fan 62 by controlling the operation amount (typically the rotation speed) of the cooling fan 62. .

  HV-ECU 100 sets outputable power WOUT of power storage device 60 based on the SOC and temperature of power storage device 60 received from BAT-ECU 110. HV-ECU 100 controls the power consumed by first MG 20 and second MG 30 so that the power output from power storage device 60 does not exceed outputable power WOUT.

  The navigation device 130 includes a navigation ECU 132, a map information database (DB) 134, a GPS (Global Positioning System) receiving unit 136, and a traffic information receiving unit 138.

  The map information DB 134 is configured by a hard disk drive (HDD) or the like, and stores map information. The map information includes data on “nodes” such as intersections and dead ends, “links” connecting the nodes, and “facility” (buildings, parking lots, etc.) along the links. Map information includes location information for each node, distance information for each link, road type information included in each link (such as tunnels, bridges, elevated roads, roads along the sea, mountains, etc.), gradient information for each link, etc. including.

  The GPS receiving unit 136 acquires the current position of the vehicle 1 based on a signal (radio wave) from a GPS satellite (not shown), and outputs a signal indicating the current position of the vehicle 1 to the navigation ECU 132.

  The traffic information receiving unit 138 receives road traffic information (for example, VICS (registered trademark) information) provided by FM multiplex broadcasting or the like. This road traffic information includes at least traffic jam information, and may also include other road regulation information and parking lot information. This road traffic information is updated every 5 minutes, for example.

  The navigation ECU 132 includes a CPU, a ROM, a RAM, an input / output port (not shown), and the like. Based on various information and signals received from the map information DB 134, the GPS receiving unit 136, and the traffic information receiving unit 138, the navigation ECU 132 The position, surrounding map information, traffic jam information, and the like are output to the HMI device 140 and the HV-ECU 100.

  In addition, when the destination of the vehicle 1 is input by the user in the HMI device 140, the navigation ECU 132 searches for a route (scheduled travel route) from the current position of the vehicle 1 to the destination based on the map information DB 134. This scheduled travel route is configured by a set of nodes and links from the current position of the vehicle 1 to the destination. Then, navigation ECU 132 outputs a search result (a set of nodes and links) from the current position of vehicle 1 to the destination to HMI device 140.

  Further, in response to a request from the HV-ECU 100, the navigation ECU 132 also includes map information and road traffic information (hereinafter also referred to as “prefetching information”) from the current position to a point within a predetermined distance (for example, about 10 km) in the planned travel route. .) To the HV-ECU 100. This prefetch information is used for the downward SOC control in the HV-ECU 100 (described later).

  The HMI device 140 is a device that provides a user with information for supporting driving of the vehicle 1. The HMI device 140 is typically a display (visual information display device) provided in the vehicle 1 and includes a speaker (auditory information output device) and the like. The HMI device 140 provides various information to the user by outputting visual information (graphic information, character information), auditory information (voice information, sound information), and the like.

  The HMI device 140 functions as a display for the navigation device 130. That is, the HMI device 140 receives the current position of the vehicle 1 and its surrounding map information and traffic jam information from the navigation device 130 through the CAN 150, and displays the current position of the vehicle 1 together with the map information and traffic jam information of the surrounding area. .

  The HMI device 140 also operates as a touch panel that can be operated by the user. The user touches the touch panel to change the scale of the displayed map or input the destination of the vehicle 1, for example. can do. When the destination is input in the HMI device 140, information on the destination is transmitted to the navigation device 130 through the CAN 150.

  As described above, the navigation ECU 132 sends the above-described prefetch information (map information and road traffic information from the current position on the planned travel route to a point within a predetermined distance) to the HV-ECU 100 in response to a request from the HV-ECU 100. Output.

  When the HV-ECU 100 receives the prefetch information from the navigation ECU 132, the HV-ECU 100 determines whether or not there is a target downlink section (control target section) that satisfies a predetermined downlink extraction condition on the planned travel route using the received prefetch information. If there is a downward section, “downward SOC control” is executed to reduce the SOC of the power storage device 60 in advance before entering the section. The downward SOC control is one of the controls for supporting the energy saving operation of the vehicle 1. Details of the downlink SOC control will be described in detail later.

<Running control>
Prior to detailed description of the down SOC control, first, the traveling control of the vehicle 1 executed by the HV-ECU 100 will be described.

  FIG. 3 is a flowchart illustrating an example of a processing procedure of travel control executed by the HV-ECU 100. A series of processing shown in this flowchart is repeatedly executed at predetermined time intervals when the system switch of the vehicle 1 is turned on, for example.

  The HV-ECU 100 acquires the detected values of the accelerator opening degree ACC and the vehicle speed VS from the accelerator pedal sensor 122 and the vehicle speed sensor 124, respectively, and acquires the SOC of the power storage device 60 from the BAT-ECU 110 (step S10).

  Next, the HV-ECU 100 calculates a required torque Tr for the vehicle 1 based on the acquired detected values of the accelerator opening ACC and the vehicle speed VS (step S15). For example, a map indicating the relationship between the accelerator opening ACC, the vehicle speed VS, and the required torque Tr is prepared in advance and stored as a map in the ROM of the HV-ECU 100, and the accelerator opening ACC is used using the map. The required torque Tr can be calculated based on the detected value of the vehicle speed VS. Then, the HV-ECU 100 calculates the traveling power Pd (required value) for the vehicle 1 by multiplying the calculated required torque Tr by the vehicle speed VS (step S20).

  Subsequently, HV-ECU 100 calculates charge / discharge required power Pb for power storage device 60 (step S25). This charge / discharge required power Pb is calculated based on the difference ΔSOC between the SOC (actual value) of power storage device 60 and its target. When charge / discharge required power Pb is a positive value, It indicates that charging is required, and when the charge / discharge required power Pb is a negative value, it indicates that the power storage device 60 is required to be discharged.

  FIG. 4 is a diagram showing an example of a method for calculating charge / discharge required power Pb for power storage device 60. When the difference ΔSOC between the SOC (actual value) of power storage device 60 and the target SOC indicating the SOC control target is a positive value (SOC> target SOC), charge / discharge request power Pb becomes a negative value (discharge request). ), The larger the absolute value of ΔSOC, the larger the absolute value of the charge / discharge required power Pb. On the other hand, when ΔSOC is a negative value (SOC <target SOC), charge / discharge required power Pb becomes a positive value (charge request), and the absolute value of charge / discharge required power Pb increases as the absolute value of ΔSOC increases. . In this example, when the absolute value of ΔSOC is small, a dead zone in which the charge / discharge required power Pb is 0 is provided.

  Returning to FIG. 3, the HV-ECU 100, as shown in the following equation (1), the traveling power Pd calculated in step S 20, the charge / discharge required power Pb calculated in step S 25, and the system loss Ploss, Is calculated from the required engine power Pe required for the engine 10 (step S30).

Pe = Pd + Pb + Ploss (1)
Next, the HV-ECU 100 determines whether or not the calculated engine required power Pe is larger than a predetermined engine start threshold value Peth (step S35). The threshold value Peth is set to a value at which the engine 10 can be operated with an operation efficiency higher than a predetermined operation efficiency.

  If it is determined in step S35 that engine required power Pe is greater than threshold value Peth (YES in step S35), HV-ECU 100 controls engine 10 to start engine 10 (step S40). If the engine 10 is already in operation, this step is skipped. Then, HV-ECU 100 controls engine 10 and PCU 50 so that vehicle 1 travels using outputs from both engine 10 and second MG 30. That is, vehicle 1 performs hybrid travel (HV travel) using the outputs of engine 10 and second MG 30 (step S45).

  On the other hand, when it is determined in step S35 that engine required power Pe is equal to or less than threshold value Peth (NO in step S35), HV-ECU 100 controls engine 10 to stop engine 10 (step S50). . If the engine 10 is already stopped, this step is skipped. Then, HV-ECU 100 controls PCU 50 so that vehicle 1 travels using only the output of second MG 30. That is, vehicle 1 performs electric motor travel (EV travel) using only the output of second MG 30 (step S55).

  In the above, when the actual SOC is higher than the target SOC (ΔSOC> 0), the charge / discharge required power Pb becomes a negative value, so that the engine is compared with the case where the SOC is controlled to the target SOC. It will be understood that the engine 10 becomes difficult to start when the required power Pe decreases. As a result, the discharge of power storage device 60 is promoted, and the SOC tends to decrease.

  On the other hand, when the actual SOC is lower than the target SOC (ΔSOC <0), the charge / discharge required power Pb is a positive value, so that the engine required power Pe is compared to when the SOC is controlled to the target SOC. It will be understood that the engine 10 is likely to be started by increasing. As a result, charging of the power storage device 60 is promoted, and the SOC tends to increase.

<Details of Downlink SOC Control>
Next, details of the downward SOC control executed by the HV-ECU 100 will be described.

  As described above, the HV-ECU 100 executes “downward SOC control” as control for supporting the energy saving operation of the vehicle 1. In the present embodiment, the down SOC control is based on prefetch information (such as gradient information of map information) from the navigation device 130 as to whether or not there is a target down section that satisfies a predetermined down extraction condition on the planned travel route of the vehicle 1. If there is a target down section, the SOC of the power storage device 60 is reduced in advance before entering the section.

  When the vehicle 1 travels in the target downward section, the SOC of the power storage device 60 increases due to the increase in the regenerative power of the second MG 30. However, since the SOC of the power storage device 60 is reduced in advance before entering the target down section by the down SOC control, the SOC reaches the upper limit value SU (see FIG. 5) during traveling in the target down section (SOC Overflow) is suppressed, and fuel consumption reduction due to discarding recoverable energy and deterioration due to overcharging of power storage device 60 are suppressed (see FIG. 5 described later).

  FIG. 5 is a diagram for explaining the downlink SOC control. In FIG. 5, the horizontal axis indicates each point on the planned travel route of the vehicle 1. In the example shown in FIG. 5, sections (links) 1 to 8 included in the planned travel route are shown. The vertical axis indicates the altitude of the road on the planned travel route of the vehicle 1 and the SOC of the power storage device 60. In the figure, line L21 indicates the target SOC of power storage device 60. A line L22 indicates the transition of the SOC when the downward SOC control is executed, and the dotted line L23 indicates a transition of the SOC when the downward SOC control is not executed as a comparative example.

  The HV-ECU 100 acquires the current position of the vehicle 1, the planned travel route and map information thereof from the navigation device 130, and sets the downward extraction condition within a predetermined distance (for example, 10 km) from the current position of the vehicle 1 on the planned travel route. A “control target search process” is performed to determine whether or not there is a target downlink section that is satisfied (hereinafter also simply referred to as “target downlink section B”).

  In the present embodiment, the downward extraction condition is a section from a start point of a downhill with a large downward slope to a point immediately before the next flatness of a certain distance or more, and an altitude difference and distance of a certain value or more. It is set as a condition that is a certain section. A section satisfying the downlink extraction condition is extracted as the target downlink section B.

  FIG. 5 illustrates a case where the search for the target downlink section B is performed at the point P20 and the sections 4 to 6 are identified as the target downlink section B. HV-ECU 100 sets the target SOC of power storage device 60 to value Sn during normal travel (for example, section 1). If the vehicle 1 enters the downhill section (section 4 to section 6) while the SOC of the power storage apparatus 60 is controlled to the value Sn, the regenerative power generation is performed by the second MG 30 in the downhill section, whereby the power storage apparatus 60 is Since the battery is charged, the SOC increases from the value Sn (dotted line L23). When the SOC reaches the upper limit value SU during traveling in the downhill section (point P25a), the electric power regenerated by the second MG 30 can be stored in the power storage device 60 even though the SOC is traveling downhill. (Overflow occurs), recoverable energy is discarded, and deterioration of the power storage device 60 can be promoted.

  Therefore, in the vehicle 1 according to the present embodiment, the target downlink section B (section 4 to section 6) that satisfies the downlink extraction condition is specified, and the vehicle 1 is located at a point P21a that is a predetermined distance before the start point P23 of the target downlink section B. HV-ECU 100 changes the target SOC to a value Sd lower than value Sn (line L21). Then, the SOC becomes higher than the target SOC (ΔSOC> 0), and as described above, the discharge of power storage device 60 is promoted, and the SOC decreases (line L22).

  In FIG. 5, the SOC has decreased to the value Sd before the vehicle 1 reaches the start point P23 of the target downward section B. This suppresses the SOC from reaching the upper limit value SU during traveling in the target descending section B (section 4 to section 6), resulting in a decrease in fuel consumption due to discarding recoverable energy and deterioration due to overcharging of the power storage device 60. It is suppressed.

  When the vehicle 1 reaches the end point P26 of the target downward section B, the HV-ECU 100 ends the downward SOC control and returns the target SOC to the value Sn.

  Hereinafter, the section from the point P21a (starting point of the downward SOC control) where the target SOC is changed from the value Sn to the value Sd to the starting point P23 of the target downward section B is also referred to as “pre-downstream section A”. Further, a section (a section in which the target SOC is changed from the value Sn to the value Sd), which is a combination of the section A before downlink and the target downlink section B, is also referred to as a “down SOC control section”.

  Thus, by performing the downward SOC control, the target SOC is changed to a value Sd lower than the value Sn before entering the target downward section B. Thereby, the discharge of power storage device 60 is promoted, and a large amount of power of power storage device 60 is consumed. As a result, it is possible to increase the amount of recovered regenerative power during traveling in the target downlink section B.

<Suppression of regenerative power loss due to temperature rise of power storage device>
When the above-described downward SOC control is executed, due to the temperature rise of the power storage device 60, the regenerative electric power is lost during traveling or passing through the target downward section B (a part of the kinetic energy of the vehicle 1 is used as the regenerative electric power). There is a concern that the power storage device 60 may not be recovered and may be discarded after being converted into heat or the like by operating a friction brake (not shown).

  Specifically, in the downward SOC control, as described above, a large amount of electric power of the power storage device 60 is consumed before entering the target downward section B, thereby collecting the regenerative power during traveling in the target downward section B. Control to increase the amount. Therefore, when the downward SOC control is executed, the continuous charging time of the power storage device 60 in the target downward section B becomes longer than normal time (when the downward SOC control is not executed), and the temperature of the power storage device 60 is higher than normal time. May also rise.

  In the present embodiment, as described above, when the temperature of power storage device 60 exceeds the limit threshold value, acceptable power WIN of power storage device 60 is the normal value (the temperature of power storage device 60 is the limit threshold value). It is narrowed down to a value smaller than the value in the case of less than. Therefore, if the temperature of power storage device 60 exceeds the limit threshold during traveling or passing through target downward section B due to the execution of the downward SOC control, acceptable power WIN of power storage device 60 becomes a value smaller than the normal value. There is concern that the power will be squeezed out and the regenerative power will be lost.

  Therefore, the HV-ECU 100 according to the present embodiment sets the operation amount of the cooling fan 62 to a value larger than the normal value when the downward SOC control is being executed, compared to the case where the downward SOC control is not being executed. . As a result, the cooling capacity of power storage device 60 by cooling fan 62 is enhanced, so that the temperature increase of power storage device 60 can be further suppressed. Therefore, it is difficult to limit the acceptable power WIN of the power storage device 60 during traveling or after passing through the target downward section B. As a result, it is possible to easily suppress a loss of regenerative power due to the temperature increase of the power storage device 60 due to the execution of the downward SOC control during traveling or after passing through the target downward section B.

<Processing Flow of Downlink SOC Control>
FIG. 6 is a flowchart showing a processing procedure of the downward SOC control executed by the HV-ECU 100. The series of processing shown in this flowchart is repeatedly executed at predetermined time intervals when the system switch of the vehicle 1 is turned on, for example.

  The HV-ECU 100 determines whether it is the update timing of the prefetch information (step S110). As described above, the prefetch information is map information and road traffic information from the current position to a point within a predetermined distance (for example, about 10 km) on the planned travel route. For example, when the travel route of the vehicle 1 is changed (when the vehicle 1 leaves the planned travel route) or when the road traffic information is updated, the read-ahead information is updated at a predetermined time (for example, 1 minute). When the vehicle travels a predetermined distance, or when the vehicle 1 passes through the target descending section B.

  If it is determined in step S110 that it is not the prefetch information update timing (NO in step S110), HV-ECU 100 proceeds to step S120 without executing step S115.

  If it is determined in step S110 that it is the update timing of the prefetch information (YES in step S110), the HV-ECU 100, based on the information on the planned travel route acquired from the navigation device 130, the target downlink section that is the control target. B search processing is executed (step S115).

  When the search process for the target downlink section B is completed, the HV-ECU 100 determines whether or not the target downlink section B exists on the planned travel route (step S120). If it is determined in step S120 that there is no target downward section B on the planned travel route (NO in step S120), HV-ECU 100 proceeds to a return without executing a series of subsequent processes.

  If it is determined in step S120 that the target down section B is on the planned travel route (YES in step S120), HV-ECU 100 starts from the current position of vehicle 1 to the start point of target down section B based on the prefetch information. Distance dtag is calculated (step S125).

  Next, the HV-ECU 100 determines whether or not the distance dtag calculated in step S125 is shorter than the predetermined distance Dsoc (step S130).

  If distance dtag is equal to or greater than distance Dsoc (NO in step S130), HV-ECU 100 shifts the process to return without performing the subsequent processes.

  If it is determined in step S130 that distance dtag is shorter than distance Dsoc (YES in step S130), HV-ECU 100 starts the downward SOC control (step S135). Specifically, as described with reference to FIG. 5, HV-ECU 100 changes target SOC of power storage device 60 from value Sn to value Sd lower than value Sn.

  Next, the HV-ECU 100 determines whether or not the distance dtag calculated in step S125 is shorter than the predetermined distance Dbfan (step S136). This determination is a process for determining whether or not to increase the cooling capacity of the cooling fan 62. The predetermined distance Dbfan can be set to the same value as the predetermined distance Dsoc or a value smaller than the predetermined distance Dsoc. When the predetermined distance Dbfan is set to the same value as the predetermined distance Dsoc, the cooling capacity of the cooling fan 62 is strengthened simultaneously with the start of the downward SOC control.

  If distance dtag is equal to or greater than predetermined distance Dbfan (NO in step S136), HV-ECU 100 sets the operating amount of cooling fan 62 to a normal value (step S137). Note that the “normal value” of the operation amount of the cooling fan 62 can be a variable value corresponding to the temperature of the power storage device 60, for example. Thereby, the cooling capacity of power storage device 60 by cooling fan 62 becomes a normal value.

  On the other hand, when it is determined in step S136 that distance dtag is shorter than predetermined distance Dbfan (YES in step S136), HV-ECU 100 sets the operation amount of cooling fan 62 to a value larger than the normal value (step). S138). The “value greater than the normal value” of the operation amount of the cooling fan 62 may be a variable value corresponding to the temperature of the power storage device 60 as in the normal value, or may be the maximum output of the cooling fan 62. In any case, by setting the operation amount of the cooling fan 62 to a value larger than the normal value during execution of the downward SOC control, the cooling capacity of the power storage device 60 by the cooling fan 62 is higher than the normal value. Larger value.

  Next, the HV-ECU 100 determines whether or not the vehicle 1 has passed the end point of the target descending section B (step S140). When the vehicle 1 has not passed the end point of the target descending section B (NO in step S140), the HV-ECU 100 shifts the process to return.

  If it is determined in step S140 that vehicle 1 has passed the end point of target downward section B (YES in step S140), HV-ECU 100 ends the downward SOC control (step S145). Specifically, HV-ECU 100 returns target SOC of power storage device 60 from value Sd to value Sn.

  As described above, the HV-ECU 100 according to the present embodiment causes the operating amount of the cooling fan 62 to be larger than the normal value when the downward SOC control is being executed, compared with the case where the downward SOC control is not being executed. By setting the value, the cooling capacity of the power storage device 60 by the cooling fan 62 is strengthened. As a result, the temperature rise of power storage device 60 can be further suppressed, so that the acceptable power WIN of power storage device 60 is less likely to be limited during traveling or after passing through target downward section B. As a result, it is possible to easily suppress the loss of regenerative power during traveling or after passing through the target descending section B.

[Modification]
The above-described embodiment can be modified as follows, for example.

  (1) In the flowchart shown in FIG. 6 described above, an example in which the HV-ECU 100 increases the cooling capacity of the cooling fan 62 when the distance dtag is shorter than the predetermined distance Dbfan during execution of the downward SOC control (step S136). Indicated.

  However, the conditions for increasing the cooling capacity of the cooling fan 62 are not limited to this. For example, the cooling capacity of the cooling fan 62 is increased when the distance dtag is shorter than the predetermined distance Dbfan and the temperature of the power storage device 60 is equal to or higher than a predetermined value during execution of the downward SOC control. Also good.

  Further, for example, during the execution of the downward SOC control, the cooling capacity of the cooling fan 62 is increased regardless of whether the distance dtag is shorter than the predetermined distance Dbfan (that is, the determination process of step S138 is performed without performing the determination process of step S136). Processing).

  (2) In the above-described embodiment, the example in which the air-cooled cooling fan 62 is used as the cooling device for the power storage device 60 has been described.

  However, the cooling device of power storage device 60 is not limited to air cooling. For example, a water-cooled cooling device may be provided instead of or in addition to the cooling fan 62 described above. When providing a water-cooled cooling device, the HV-ECU 100 may increase the cooling capacity of the water-cooled cooling device by adjusting the flow rate and temperature of the coolant in the water-cooled cooling device.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present disclosure is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  1 Vehicle, 10 Engine, 20 1st MG, 30 2nd MG, 40 Power split device, 50 PCU, 60 Power storage device, 61 Monitoring unit, 62 Cooling fan, 80 Drive wheel, 100 HV-ECU, 110 BAT-ECU, 120 Various Sensor, 122 Accelerator pedal sensor, 124 Vehicle speed sensor, 126 Brake pedal sensor, 130 Navigation device, 132 Navigation ECU, 134 Map information DB, 136 GPS receiving unit, 138 Traffic information receiving unit, 140 HMI device, 150 CAN.

Claims (1)

A control device for an electric vehicle including a running motor driven by electric power of a power storage device,
A cooling unit configured to cool the power storage device;
A control unit configured to be able to execute a downward SOC control that reduces in advance the amount of power stored in the power storage device before entering the target downward section when there is a target downward section on the planned travel route of the electric vehicle,
The said control part is a control apparatus of the electric vehicle which enlarges the operating quantity of the said cooling part when the said downward SOC control is performed compared with the case where the said downward SOC control is not performed.

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