JP6321513B2 - Vehicle control device and vehicle - Google Patents

Description

  The present invention relates to a vehicle control device and a vehicle. In particular, a vehicle that can switch between a first travel mode that travels by the driving force of the drive motor while the power generation device is stopped and a second travel mode that travels by the driving force of the drive motor while generating power by the power generation device. The present invention relates to a control device and a vehicle.

  2. Description of the Related Art In recent years, an electric vehicle including a drive motor that outputs a driving force of a vehicle and an engine that is used as power for a power generation device, and a secondary battery that can be charged by an on-vehicle power generation device and an external charging device Are known. In one aspect of such an electric vehicle, the engine is used as a range extender (cruising range extension device), and when the remaining capacity (SOC: State of Charge) of the secondary battery becomes equal to or lower than a predetermined threshold while the vehicle is running. To start. The electric power generated by the engine power is supplied to the drive motor or the secondary battery is charged.

  The basic concept of such a vehicle (hereinafter also referred to as “range extender vehicle”) is to run with electric power charged in the secondary battery without activating the in-vehicle power generation device. Accordingly, the range extender vehicle travels only with the electric power stored in the secondary battery, for example, during the period from when the secondary battery is fully charged to when the remaining capacity becomes extremely small (hereinafter, this travel mode is referred to as “first mode”). Also referred to as “1 driving mode”). That is, during this period, power generation by the power generation device is not performed. On the other hand, the range extender vehicle starts power generation when the remaining capacity of the secondary battery becomes extremely small, and travels using the generated power and the power of the secondary battery (hereinafter, this travel mode is also referred to as “second travel mode”). Say.).

  Here, the secondary battery has a property that deterioration easily proceeds when used in a state where the remaining capacity is reduced at a low temperature. Patent Document 1 discloses a technique for changing a threshold value for determining whether to start power generation by an in-vehicle power generation device according to the temperature of a secondary battery. Specifically, Patent Document 1 discloses an electric vehicle in which charging of a power storage device (secondary battery) by an on-vehicle power generation mechanism is started when the estimated SOC value reaches a control lower limit value while the vehicle is traveling. ing. In such an electric vehicle, the control lower limit value is increased more than usual when the temperature of the power storage device is low and / or when the power storage device is deteriorated.

JP 2011-240863 A

  Secondary batteries have the property of self-heating due to repeated charge and discharge, and the temperature rises. Therefore, during the traveling of the range extender vehicle, it is effective to raise the control lower limit value according to the temperature of the secondary battery by the control described in Patent Document 1 regardless of the outside air temperature.

  On the other hand, at the time of starting the range extender vehicle, since the secondary battery does not self-heat, the temperature of the secondary battery is greatly influenced by the outside air temperature. For this reason, if the range extender vehicle is started in the environment where the outside air temperature is low, such as in winter or in a cold region, the remaining capacity of the secondary battery is reduced, and the vehicle continues to run using only the power of the secondary battery. There is a risk that the secondary battery will deteriorate significantly. Therefore, when the outside air temperature is low at the start of the range extender vehicle, it is desirable to shift to the second traveling mode at an early stage in order to suppress the deterioration of the secondary battery.

  However, if the judgment condition is only that the outside air temperature is low, the power generation device will always operate in winter or in cold regions, etc., and take advantage of the benefits of electric vehicles that are advantageous for fuel economy and exhaust gas. Can not be.

  The present invention has been made in view of the above problems, and an object of the present invention is to promote the deterioration of the secondary battery in the cold zone without significantly reducing the travel distance by only the power of the secondary battery. It is an object of the present invention to provide a vehicle control device and a vehicle capable of reducing the above.

  In order to solve the above-described problem, according to an aspect of the present invention, a first travel mode in which the power generation device is stopped and the drive motor is driven by the driving force of the drive motor, and the drive motor is configured to generate power by the power generation device. In a vehicle control device capable of switching between a second travel mode that travels by driving force, a remaining capacity detection unit that detects a remaining capacity of a secondary battery that supplies power to the drive motor, and the remaining capacity is predetermined A mode switching unit that switches the travel mode from the first travel mode to the second travel mode when the vehicle is less than the determination threshold, and a determination threshold for start time that is used for determination of the vehicle by the mode switching unit There is provided a vehicle control device comprising: a start time determination threshold value setting unit that sets the value based on the outside air temperature.

  The start-time determination threshold value setting unit may set the start-time determination threshold value based on an average temperature at the start of the most recent predetermined period.

  The start-time determination threshold value setting unit may set the start-time determination threshold value based on a difference between a measured value of the outside air temperature measured when the vehicle is started and the average temperature.

  Further, the start time determination threshold value setting unit is at least one of a total travel distance, a total travel time, a charge / discharge integration time from the start of use of the secondary battery, or an elapsed number of days after the secondary battery is manufactured. The determination threshold for starting time may be corrected based on the information.

  The mode switching unit may make a determination using a determination threshold for travel after the vehicle is started.

  The mode switching unit may switch the travel mode from the second travel mode to the first travel mode only when the secondary battery is charged by an external charging device.

  In order to solve the above problem, according to another aspect of the present invention, any one of the above-described control devices, a drive motor that drives a vehicle, a secondary battery that supplies power to the drive motor, There is provided a vehicle including a power generation device that generates electric power to be supplied to at least one of the drive motor and the secondary battery.

  In order to solve the above-mentioned problem, according to still another aspect of the present invention, a first traveling mode in which the traveling power is driven by a driving force of a driving motor while the auxiliary power generation device is stopped, and the auxiliary power generation device is provided. In a vehicle control device capable of switching between a second travel mode that travels by the driving force of the vehicle, a remaining capacity detection unit that detects a remaining capacity of a secondary battery that supplies power to the drive motor, and the remaining capacity is A mode switching unit that switches the travel mode from the first travel mode to the second travel mode when the threshold is less than a predetermined determination threshold, and a determination for start time that is used for determination at the start of the vehicle by the mode switching unit There is provided a vehicle control device including a start-time determination threshold value setting unit that sets a threshold value based on an outside air temperature.

  In order to solve the above problem, according to still another aspect of the present invention, a control device, a drive motor that drives a vehicle, a secondary battery that supplies electric power to the drive motor, and the drive motor, Separately, a vehicle is provided that includes an auxiliary power generation device that generates a driving force of the vehicle.

  According to the vehicle control device and the vehicle according to the present invention, it is possible to reduce the progress of deterioration of the secondary battery in the cold zone without significantly reducing the travel distance only by the power of the secondary battery.

FIG. 1 is a schematic diagram showing a schematic configuration of an entire vehicle system according to an embodiment of the present invention. FIG. 2 is a block diagram illustrating a configuration example of the travel control device. FIGS. 3A to 3C are examples of maps used for the calculation of the determination threshold for starting time. FIG. 4 is a flowchart showing the RE mode switching determination process. FIG. 5 is a flowchart showing the calculation process of the determination threshold value for starting. FIG. 6 is a flowchart showing EV mode return determination processing. FIG. 7 is a time chart when the RE mode switching determination process using only the determination threshold for traveling is performed. FIG. 8 is a time chart when the RE mode switching determination process according to the present embodiment is performed. FIG. 9 is a schematic diagram illustrating a configuration example of a system of a fuel cell hybrid vehicle. FIG. 10 is a schematic diagram illustrating a configuration example of a system of a compressed air hybrid vehicle.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

<< 1. Example of overall system configuration >>
First, an example of the overall configuration of an electric vehicle system according to an embodiment of the present invention will be described. FIG. 1 is a schematic diagram illustrating a configuration example of an electric vehicle system 1 according to the present embodiment. In FIG. 1, a solid line indicates power, a dotted line indicates power, and a broken line indicates an electrical signal.

  The system 1 includes a drive system that generates a drive force applied to the drive shaft 50 of the vehicle by the drive motor 30, a power generation system that generates power to be supplied to the drive motor 30 and the secondary battery 40 by the power generation device 14, and a drive. And an electronic control system that controls the power generation system. The power generation system also corresponds to an auxiliary power generation device. The system 1 is configured as a so-called range extender vehicle, but may be referred to as a series hybrid vehicle capable of charging the secondary battery 40 with an external charging device.

  The drive system is mainly composed of a secondary battery 40, an inverter 20, and a drive motor 30. The power generation system is mainly composed of the engine 12, the power generation device 14 and the inverter 16. The electronic control system is mainly composed of a travel control device (indicated as “ECU” in FIG. 1) 100 and an engine control device (indicated as “engine ECU” in FIG. 1) 60.

  In such a system 1, basically, only the electric power charged in the secondary battery 40 is used to generate a driving force by the driving motor 30 to perform vehicle driving control (hereinafter, the driving mode is referred to as “EV”). Mode "or" first running mode "). Further, in such a system 1, when the remaining capacity SOC of the secondary battery 40 becomes less than the predetermined threshold value SOC_thre, the driving power is generated by the driving motor 30 while the power generation device 14 generates power, and the vehicle travels. Control is performed. (Hereinafter, this travel mode is referred to as “RE (Range Extend) mode” or “second travel mode”).

<1-1. Structure of drive system>
The drive motor 30 constituting the drive system is connected to the secondary battery 40 via the inverter 20 that converts DC power into AC power. The drive motor 30 generates a drive force applied to the drive shaft 50 by an electromagnetic force generated by the current supplied from the inverter 20 and a magnetic force of a magnet provided in the drive motor 30. Further, the drive motor 30 may have a regeneration function of charging the secondary battery 40 by converting deceleration energy that is discarded as heat energy during deceleration into electric power.

  The drive motor 30 is configured as a three-phase AC motor. In such a motor, a three-phase alternating current is supplied to the three-phase winding of the stator coil to generate a rotating magnetic field in the motor, and a permanent magnet provided on the rotor is generated by the rotating magnetic field to generate torque. The torque generated at this time is proportional to the magnitude of the current supplied to the motor. The frequency of the alternating current supplied to the motor is set according to the output torque and the rotational speed of the motor.

  The secondary battery 40 is comprised by secondary batteries, such as a storage battery which can be charged / discharged, for example. In the system 1 according to the present embodiment, a high voltage secondary battery 40 having a voltage of 200 V is used. The inverter 20 supplies a current to the motor winding of the drive motor 30 by applying the voltage of the secondary battery 40 to the drive motor 30. Inverter 20 may be an inverter with a boost converter.

<1-2. Configuration of power generation system>
The power generation device 14 constituting the power generation system is configured as a device that generates power using the driving force of the engine 12. Similar to the drive motor 30, the power generator 14 is configured as a three-phase AC motor. The power generator 14 is connected to an inverter 20 and a secondary battery 40 that constitute a drive system via an inverter 16 that converts AC power into DC power. The generated power is supplied to the drive motor 30 via the inverters 16 and 20 and the secondary battery 40 is charged. Inverter 16 may be configured as an inverter with a boost converter.

  The engine 12 generates power for power generation by the power generation device 14. The engine 12 can be, for example, a gasoline engine or a diesel engine, but is not limited thereto. The power generation device 14 may be configured to function as a starter using the electric power from the secondary battery 40 when the engine 12 is started.

<1-3. Configuration of electronic control system>
The electronic control system of the system 1 according to the present embodiment includes a travel control device 100 and an engine control device 60. The electronic control system may be configured by a single control device in which the travel control device and the engine control device are integrated, or the travel control device may be further divided into a plurality of control devices.

  For example, the engine control device 60 is configured around a known microcomputer, and performs drive control of the engine 12 in a state where the travel mode is set to the RE mode (second travel mode). For example, the engine control device 60 performs fuel injection control, intake control, and the like of the engine 12. In the present embodiment, since the engine 12 is used to generate power for the power generation device 14, the engine speed and the output torque may be fixed or may be switched in a plurality of stages.

  The travel control device 100 is, for example, a control unit configured around a known microcomputer. The travel control device 100 calculates the required torque of the drive motor 30 based on the amount of operation of the accelerator pedal by the driver. The traveling control device 100 controls the drive system inverter 20 based on the calculated required torque, and generates a desired driving force by the drive motor 30.

  Moreover, the traveling control device 100 switches the traveling mode of the vehicle to the EV mode (first traveling mode) or the RE mode (second traveling mode). In the EV mode, the travel control device 100 executes the output control of the drive motor 30 described above. In the RE travel mode, the travel control device 100 gives a command to the engine control device 60 and controls the inverter 16 of the power generation system in addition to the output control of the drive motor 30 described above, and controls the driving force of the engine 12. The power generation control used is executed.

  FIG. 2 is a block diagram functionally showing a part related to the switching of the driving mode in the configuration of the driving control device 100 constituting the electronic control system. The travel control device 100 includes an outside air temperature detection unit 110, an SOC detection unit 120, a startup determination threshold setting unit 130, an external charge detection unit 140, a mode switching unit 160, and a storage unit 150. Among these, the outside air temperature detection unit 110, the SOC detection unit 120, the start time determination threshold value setting unit 130, the external charge detection unit 140, and the mode switching unit 160 are specifically functions realized by executing a program by a microcomputer. It may be.

  The storage unit 150 includes, for example, a volatile RAM (Random Access Memory). In addition, the traveling control apparatus 100 may include a ROM (Read Only Memory) (not shown) that stores a control program and the like. The travel control device 100 receives a signal related to the remaining capacity SOC of the secondary battery 40, a signal indicating on / off of an ignition switch of the vehicle, a detection signal of a temperature sensor, and the like.

  The outside air temperature detection unit 110 reads the detection signal of the temperature sensor, obtains the outside air temperature Ta based on the detection signal, and stores it in the storage unit 150. The temperature sensor can be, for example, a temperature sensor that detects the temperature of engine cooling water, but is not limited thereto. Detection signals of various temperature sensors provided in the vehicle may be used, or individual temperature sensors may be provided. In the present embodiment, the outside air temperature detection unit 110 detects the outside air temperature Ta when the ignition switch of the vehicle is turned on, and stores the detected outside air temperature Ta in the storage unit 150. As a result, the temperature change factor other than the outside air temperature Ta in the running state of the vehicle is minimized as much as possible, and the outside air temperature Ta is easily detected accurately.

  The SOC detection unit 120 reads a signal related to the remaining capacity SOC of the secondary battery 40 and obtains the remaining capacity SOC of the secondary battery 40. In the present embodiment, the remaining capacity SOC indicates the current charge amount (%) with respect to the maximum value of the charge capacity of the secondary battery 40. The signal related to the remaining capacity SOC can be, for example, a sensor signal of a voltage sensor or a current sensor provided in the secondary battery 40. Since the maximum value of the charging capacity changes according to the temperature Tb of the secondary battery 40, the SOC detection unit 120 may consider the temperature Tb of the secondary battery 40 when obtaining the remaining capacity SOC.

  The external charging detection unit 140 detects a state in which the secondary battery 40 is charged by the external charging device, not the in-vehicle power generation device 14. For example, it can be determined that charging by the external charging device is performed when the charging gun of the external charging device is inserted into the connector for charging the secondary battery 40. Alternatively, in the case of a non-contact external charging device, it can be determined that charging by the external charging device is performed by wireless communication with the external charging device or a weak current for confirming the start of charging.

  The mode switching unit 160 compares the remaining capacity SOC (%) of the secondary battery 40 detected by the SOC detection unit 120 with a predetermined determination threshold SOC_thre (%). Then, mode switching unit 160 shifts the traveling mode from the EV mode to the RE mode when the remaining capacity SOC becomes less than determination threshold SOC_thre. Thus, during the period from when the secondary battery 40 is fully charged until the remaining capacity SOC decreases, the vehicle basically travels using only the electric power charged in the secondary battery 40. Therefore, as much as possible, the vehicle travels in an EV mode that does not consume fuel supplied to the engine 12 and does not release exhaust gas.

  On the other hand, when the remaining capacity SOC of the secondary battery 40 decreases, the vehicle travels in the RE mode using the power generated by the power generation device 14. Thus, the vehicle can be driven by the in-vehicle power generation device 14 until the secondary battery 40 is charged by the external charging device. In the present embodiment, the mode switching unit 160 uses the travel time determination threshold SOC_0 and the start time determination threshold SOC_st as the predetermined determination threshold SOC_thre.

  The running time determination threshold value SOC_0 is used in most periods except when the ignition switch of the vehicle is changed from OFF to ON, and is compared with the remaining capacity SOC. That is, after the vehicle starts to travel and the temperature Tb of the secondary battery 40 starts to increase due to self-heating, the determination threshold value SOC_0 for traveling is used. Since the temperature of the secondary battery 40 is less likely to be affected by the outside air temperature Ta after the vehicle starts running, the running determination threshold value SOC_thre is equal to the reference for the starting determination threshold value SOC_st regardless of the surrounding environment. The value can be the same as the lower limit value of the value SOC_X. The determination threshold value SOC_thre for travel time is set to 2 to 6.5%, for example.

  On the other hand, the determination threshold value SOC_st for starting is used only when the ignition switch of the vehicle is changed from OFF to ON, and is compared with the remaining capacity SOC. That is, in the state where the vehicle is stopped and the temperature Tb of the secondary battery 40 is greatly influenced by the outside air temperature Ta, the starting determination threshold value SOC_st is used. When the vehicle is started in an environment where the outside air temperature Ta is low, such as in winter or in a cold region, the judgment for starting is performed for the purpose of preventing the deterioration of the secondary battery 40 by switching to the RE mode at an early stage. A threshold SOC_st is used.

  The mode switching unit 160 transmits a control command for the engine 12 to the engine control device 60 when the travel mode is switched to the RE mode. In addition, when the travel mode is switched to the RE mode, the travel control device 100 controls the power generation system inverter 16 to perform power generation control. In the RE mode, for example, the power generation system is controlled such that the remaining capacity SOC of the secondary battery 40 is in a range that is greater than or equal to the travel time determination threshold SOC_0 and less than or equal to a predetermined upper limit threshold.

  In the present embodiment, the mode switching unit 160 returns the travel mode from the RE mode to the EV mode only when the vehicle is connected to the external charging device and the secondary battery 40 is charged by the external charging device. Let Therefore, after the secondary battery 40 is charged by the external charging device, the vehicle basically travels in the EV mode, and after the remaining capacity SOC of the secondary battery 40 decreases, the RE mode is maintained until the secondary battery 40 is connected to the external charging device. It is possible to run in an environment-friendly manner.

  The start time determination threshold value setting unit 130 sets a start time determination threshold value SOC_st based on the outside air temperature Ta when the ignition switch of the vehicle is turned on. The start-time determination threshold value SOC_st is a threshold value used for determination in the mode switching unit 160 for switching the travel mode from the EV mode to the RE mode, and is a determination threshold value used only when the vehicle is started.

  In the present embodiment, the start-time determination threshold value setting unit 130 sets the start-time determination threshold value SOC_st (%) according to the average temperature Ta_ave obtained from the information of the plurality of outside air temperatures Ta stored in the storage unit 150. . By using the average temperature Ta_ave instead of the detected outside air temperature Ta itself, the start time determination threshold value SOC_st can be prevented from changing every day or every hour.

  Specifically, after determining the average temperature Ta_ave, the start time determination threshold setting unit 130 refers to the first map illustrated in FIG. 3A and determines the start time determination threshold corresponding to the average temperature Ta_ave. Determine SOC_st. The starting determination threshold value SOC_st determined by the first map is a value equal to or greater than the traveling determination threshold value SOC_thre used after the start of traveling. Further, the start time determination threshold value SOC_st increases as the average temperature Ta_ave decreases.

  Therefore, when the vehicle starts in an area where the average temperature Ta_ave is low or in season, the RE mode accompanied by the power generation by the power generation device 14 is likely to be performed. Accordingly, it is possible to suppress the deterioration of the secondary battery 40 from being started in the EV mode when the remaining capacity SOC of the secondary battery 40 is low at a low temperature. Further, the determination threshold value SOC_st for start-up becomes larger as the average temperature Ta_ave becomes lower, and therefore, it becomes easier to shift to the RE mode according to the degree of the low average temperature Ta_ave. As a result, the travel distance in the EV mode without power generation by the power generation device 14 is not significantly reduced.

  For example, the average temperature Ta_ave is detected by the outside air temperature detecting unit 110 when the ignition switch of the vehicle is turned on, and is stored at a plurality of recent times (for example, 5 to 10 times) of the outside air temperature Ta. It can be an average value. Or average temperature Ta_ave can be made into the average value of the value memorize | stored in the predetermined period immediately before (for example, 2 weeks to 3 months). Alternatively, for example, the average temperature Ta_ave may be obtained once a day by using a value obtained by measuring and storing the outside air temperature Ta in a predetermined time zone. Furthermore, the current position of the vehicle may be grasped by a navigation system or the like, and the average temperature closest to the current position may be acquired via a communication network.

  Further, in the present embodiment, the start-time determination threshold value setting unit 130 is based on the difference ΔTa between the above average temperature Ta_ave and the outside air temperature Ta detected when the current ignition switch is turned on. The determination threshold value SOC_st for use is corrected. Specifically, the start-time determination threshold value setting unit 130 subtracts the average temperature Ta_ave from the currently detected outside air temperature Ta to obtain the difference ΔTa, and then refers to the second map illustrated in FIG. Then, a correction value SOC_Y (%) corresponding to the difference ΔTa is obtained. Then, start-time determination threshold value setting unit 130 determines start-time determination threshold value SOC_st by adding calculated correction value SOC_Y to already-started determination threshold value SOC_st (SOC_X).

  The correction value SOC_Y determined by the second map is larger as the difference ΔTa is larger, that is, as the outside air temperature Ta detected this time is lower than the average air temperature Ta_ave. Therefore, even if the outside air temperature Ta at the start of the current vehicle is lower than the average air temperature Ta_ave, it is easy to shift to the RE mode according to the degree of the low outside air temperature Ta at the start of the vehicle. Yes. Further, when the outside air temperature Ta at the start of the current vehicle is higher than the average air temperature Ta_ave, such as when the vehicle is placed in the garage, the correction value SOC_Y is set so as to decrease the start time determination threshold SOC_st. Thus, it is possible to prevent the determination threshold value SOC_st for starting from becoming larger than necessary.

  Further, the start time determination threshold setting unit 130 may correct the start time determination threshold SOC_st based on the degree of aging deterioration of the secondary battery 40. The parameters representing the aging of the secondary battery 40 include, for example, the total travel distance from the start of use of the secondary battery 40, the total travel time, the charge / discharge integrated time, and the number of days elapsed after the secondary battery 40 is manufactured. At least one piece of information can be used. The secondary battery 40 is deteriorated every time it is used or left alone, and only about 70 to 80% of the initial performance is maintained at the end of its useful life. It has been known. Therefore, the deterioration of the secondary battery 40 can be prevented from becoming more severe by facilitating the transition to the RE mode as the deterioration of the secondary battery 40 progresses over time.

  For example, the start-time determination threshold value setting unit 130 refers to the third map illustrated in FIG. 3C, and corrects according to the total travel distance and total travel time from the start of use of the secondary battery 40. The coefficient α is obtained. In the example of the third map, the correction coefficient α increases as the total travel distance or the total travel time increases, that is, as the deterioration of the secondary battery 40 with time progresses. Then, the start time determination threshold value setting unit 130 corrects the start time determination threshold value SOC_st by multiplying the obtained correction coefficient α by the start time determination threshold value SOC_st. Thereby, in a state where the secondary battery 40 is deteriorated, it is possible to shift to the RE mode at an early stage and to drive the vehicle using the electric power generated by the power generation device 14.

<< 2. Example of control method >>
Next, a travel mode switching control method by the travel control apparatus 100 according to the present embodiment will be described. 4-6 is a flowchart which shows the driving mode switching process concerning this embodiment. 4 to 5 are processes for switching from the EV mode (first travel mode) to the RE mode (second travel mode) while the ignition switch is turned on. It is a flowchart which shows the process performed in FIG. FIG. 6 is a process for returning from the RE mode (second travel mode) to the EV mode (first travel mode), which is performed while the ignition switch is off. It is a flowchart to show.

<2-1. RE mode switching determination process>
First, a determination process for switching the travel mode from the EV mode to the RE mode will be described with reference to FIGS. First, when the ignition switch is turned on, in step S10, the mode switching unit 160 determines whether or not the current travel mode is the EV mode. If the current travel mode is the RE mode (S10: No), the travel mode is maintained in the RE mode while the ignition switch is on, so the RE mode switching determination process ends.

  On the other hand, when the current travel mode is the EV mode (S10: Yes), in step S12, the mode switching unit 160 determines whether or not it is immediately after the ignition switch is turned on from off. If it is not immediately after the ignition switch is turned on from off (S12: No), in step S18, the mode switching unit 160 sets the determination threshold SOC_thre to the travel determination threshold SOC_0. The running time determination threshold SOC_0 is a value set in advance. On the other hand, if it is immediately after the ignition switch is turned on from off (S12: Yes), in step S14, the start time determination threshold setting unit 130 calculates the start time determination threshold SOC_st.

  FIG. 5 is a flowchart showing a calculation process of the start time determination threshold value SOC_st. First, in step S30, the start time determination threshold setting unit 130 calculates an average temperature Ta_ave. Specifically, the start-time determination threshold value setting unit 130 reads the outside air temperature Ta stored in the storage unit 150, and calculates the average temperature Ta_ave in the latest multiple times, a predetermined period, or the like.

  Next, in step S <b> 32, the start time determination threshold value setting unit 130 refers to the first map illustrated in FIG. 3A and obtains the start time determination threshold value SOC_X corresponding to the average temperature Ta_ave. Next, in step S34, the start-time determination threshold value setting unit 130 subtracts the average air temperature Ta_ave from the outside air temperature Ta detected when the ignition switch is turned on this time, and calculates a difference ΔTa.

  Next, in step S36, the start-time determination threshold value setting unit 130 refers to the second map illustrated in FIG. 3B and obtains a correction value SOC_Y corresponding to the difference ΔTa. Furthermore, in step S38, the start time determination threshold value setting unit 130 refers to the third map illustrated in FIG. 3C, for example, the total travel distance and the total travel time from the start of use of the secondary battery 40. The correction coefficient α corresponding to the deterioration information is obtained.

  In step S40, the start-time determination threshold value setting unit 130 adds the correction value SOC_Y obtained in step S36 to the start-time determination threshold value SOC_X obtained in step S32, and the correction coefficient α obtained in step S38. Multiply the values to obtain the starting determination threshold value SOC_st. Note that step S34 to step S40 may be omitted, and start-time determination threshold value SOC_X may be used as start-time determination threshold value SOC_st, or step S38 may be omitted and correction value SOC_Y is added to start-time determination threshold value SOC_X. The determined value may be used as the starting determination threshold value SOC_st.

  Returning to FIG. 4, after the start time determination threshold value SOC_st is obtained in step S <b> 14, in step S <b> 16, the mode switching unit 160 sets the determination threshold value SOC_thre to the start time determination threshold value SOC_st.

  When the determination threshold SOC_thre is set in step S16 or step S18, in step S20, the mode switching unit 160 reads the current remaining capacity SOC of the secondary battery 40, and whether or not the remaining capacity SOC is less than the determination threshold SOC_thre. Is determined. When the remaining capacity SOC is equal to or greater than the determination threshold SOC_thre (S20: No), the process returns to step S10 while maintaining the traveling mode in the EV mode.

  On the other hand, when the remaining capacity SOC is less than the determination threshold SOC_thre (S20: Yes), the mode switching unit 160 switches the travel mode from the EV mode to the RE mode, and ends the RE mode switching determination process. Thus, the traveling in the EV mode is continued until the remaining capacity SOC of the secondary battery 40 becomes less than the determination threshold SOC_thre, and the mode is switched to the RE mode when the remaining capacity SOC becomes less than the determination threshold SOC_thre. Thereafter, travel control by the drive motor 30 is executed while using the power generated by the power generation device 14.

  In the present embodiment, immediately after the ignition switch is turned on from OFF, it is determined whether or not to shift the travel mode to the RE mode using the start determination threshold value SOC_st set based on the average temperature Ta_ave. Is done. For this reason, when the remaining capacity SOC is low in a low temperature environment such as a winter season or a cold region, it is possible to suppress the deterioration of the secondary battery 40 due to the start of traveling in the EV mode. The starting determination threshold value SOC_st is set to a larger value as the average temperature Ta_ave or the current outside air temperature Ta is lower, so that the travel distance in the EV mode is not significantly reduced. Furthermore, if the determination threshold value SOC_st for start-up is corrected according to the degree of deterioration of the secondary battery 40 over time, when the deterioration of the secondary battery 40 is progressing, it becomes easier to shift to the RE mode.

<2-2. EV mode return determination processing>
Next, a determination process for switching the travel mode from the RE mode to the EV mode will be described with reference to FIG. First, in step S50, the mode switching unit 160 determines whether or not the ignition switch is off. When the ignition switch is on (S50: No), the travel mode is not switched from the RE mode to the EV mode, so the EV mode switching determination process is terminated as it is.

  When the ignition switch is off (S50: Yes), in step S52, the mode switching unit 160 determines whether or not it is connected to the external charging device. For example, when the charging gun of the external charging device is inserted into the charging connector, it can be determined that the external charging device is connected. Alternatively, in the case of a non-contact external charging device, it can be determined that the external charging device is connected by wireless communication with the external charging device or a weak current for confirming the start of charging.

  When the connection to the external charging device is not detected (S52: No), the process returns to step S50, and the determination of the connection to the external charging device is repeated while the ignition switch is off. On the other hand, when the connection to the external charging device is detected (S52: Yes), in step S54, the mode switching unit 160 returns the traveling mode from the RE mode to the EV mode. As a result, the travel mode returns to the EV mode only when the secondary battery 40 is charged by the external charging device.

<2-3. Time chart>
Next, the transition time of the travel mode and the transition of the remaining capacity SOC of the secondary battery 40 when the RE mode switching determination process is executed by the travel control device 100 according to the present embodiment will be described based on the time chart. FIG. 7 is a time chart showing a case where the determination threshold value SOC_0 for travel is used over the entire period including when the vehicle is started. FIG. 8 is a time chart when the RE mode switching determination process is executed by the travel control device 100 according to the present embodiment.

  As shown in FIG. 7, in the case where the RE mode switching determination process is performed using the travel time determination threshold SOC_0 over the entire period, the EV mode continues from the time t0 when the secondary battery 40 is in the fully charged state. During this time, even if the ignition switch of the vehicle is repeatedly turned on / off, that is, even if the use of the vehicle is interrupted, as long as the remaining capacity SOC of the secondary battery 40 does not become less than the travel time determination threshold SOC_0, the vehicle travels in the EV mode. Control continues. The time point t1 and the time point t2 in FIG. 7 represent the time points when the vehicle is started. However, since the remaining capacity SOC is greater than or equal to the travel time determination threshold value SOC_0 at both the time points t1 and t2, EV The mode is continuing.

  Then, at the time point t3 when the remaining capacity SOC of the secondary battery 40 becomes less than the travel time determination threshold SOC_0, the travel mode is switched from the EV mode to the RE mode. Thereafter, the RE mode is continued until it is connected to the external charging device while the power generation by the on-vehicle power generation device 14 and the power generation stop are repeated. In the example of FIG. 7, the remaining capacity SOC is compared with the running determination threshold value SOC_0 regardless of the outside air temperature Ta. For example, when the vehicle is started in a low temperature environment during a period from time t2 to time t3, traveling control is performed using electric power charged in the secondary battery 40 at a low temperature and a low remaining capacity SOC. Therefore, the deterioration of the secondary battery 40 becomes severe.

  On the other hand, as shown in FIG. 8, when the travel control device 100 according to the present embodiment performs the RE mode switching determination process using the determination threshold value SOC_st for start time and the determination threshold value SOC_0 for travel time, the secondary battery 40 The EV mode continues from time t10 when the battery is fully charged. At times t10, t11, and t12 when the ignition switch of the vehicle is turned on from off, the start-time determination threshold value SOC_st that is set based on the average temperature Ta_ave or the outside air temperature Ta is larger than the travel-time determination threshold value SOC_0. It is a value. However, at time points t10 and t11, since the remaining capacity SOC is equal to or greater than the starting determination threshold value SOC_st, the traveling mode is maintained in the EV mode.

  On the other hand, at the time t12 when the ignition switch of the vehicle is turned on next time, the remaining capacity SOC is lower than the starting determination threshold value SOC_st. Therefore, at this time t12, the traveling mode is switched to the RE mode. Thereafter, for example, at the time t13 when the temperature of the secondary battery 40 starts to increase due to self-heating, the determination threshold SOC_thre is returned to the determination threshold SOC_0 for running. When the remaining capacity SOC exceeds the start time determination threshold value SOC_st by 2 to 5%, the determination threshold value SOC_thr may be returned to the travel time determination threshold value SOC_0. Thereafter, the RE mode is continued until it is connected to the external charging device while the power generation by the on-vehicle power generation device 14 and the power generation stop are repeated. Thereafter, unless the secondary battery 40 is charged by the external charging device, the travel control is started in the RE mode from the start of the vehicle.

  As described above, according to the present embodiment, the determination threshold value SOC_0 for travel is used after the start of travel of the vehicle, while the start that is set based on the average temperature Ta_ave or the outside air temperature Ta at the start of the vehicle. Switching to the RE mode is determined using the time determination threshold SOC_st. Therefore, at the time of starting the vehicle in which the temperature Tb of the secondary battery 40 is greatly influenced by the outside air temperature Ta, the traveling mode is easily shifted to the RE mode in a low temperature environment and when the remaining capacity SOC is low. . This suppresses the deterioration of the secondary battery 40 due to the start of traveling in the EV mode while the temperature Tb of the secondary battery 40 is low and the remaining capacity SOC is low.

  In the present embodiment, since the average temperature SOC_ave is used when setting the starting determination threshold value SOC_st, the starting determination threshold value SOC_st does not vary from day to day or from time to time. Further, in this embodiment, the start time determination threshold value SOC_st is set in consideration of the outside air temperature Ta detected at the time of the current start, and therefore, the start time determination threshold value is also reflected in the surrounding environment of the vehicle. SOC_st is set. Furthermore, in the present embodiment, the starting determination threshold value SOC_st is set in consideration of the degree of aging of the secondary battery 40. Therefore, when the deterioration of the secondary battery 40 is progressing, it becomes easier to shift to the RE mode.

  The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention pertains can make various modifications or application examples within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

  For example, in the above embodiment, the power generation system that generates power by the motor as the power generation device 14 using the power of the engine 12 is used, but the present invention is not limited to such an example. As shown in FIG. 9, a fuel cell vehicle (FCV) 3 that includes a hydrogen tank 72 and a fuel cell 74 and uses a power generation system that causes hydrogen and oxygen to react in the fuel cell 74 may be used.

  Alternatively, as shown in FIG. 10, an air tank 82, an air pump 84, and a hydraulic motor 86 are provided, and driving force is transmitted to the drive shaft 50 via a gear 88 by driving the hydraulic motor 86 with compressed air. The compressed air hybrid system 5 using a power generator may be used. In this case, after shifting to the RE mode, the drive shaft 50 is driven only by the driving force of the auxiliary power generation device, and the secondary battery 40 is not charged. Therefore, the secondary battery 40 is always charged by the external charging device.

DESCRIPTION OF SYMBOLS 1 Vehicle system 12 Engine 14 Electric power generation apparatus 16 Electric power generation system inverter 20 Drive system inverter 30 Drive motor 40 Secondary battery 50 Drive shaft 60 Engine control apparatus (engine ECU)
72 Hydrogen tank 74 Fuel cell 82 Air tank 84 Air pump 86 Hydraulic motor 88 Gear 100 Travel controller (ECU)
110 Outside air temperature detection unit 120 SOC detection unit 130 Start-up determination threshold setting unit 140 External charge detection unit 150 Storage unit 160 Mode switching unit

Claims (9)

A vehicle capable of switching between a first traveling mode in which the power generation device is stopped and traveling by the driving force of the drive motor and a second traveling mode in which the power generation device generates power and the driving motor is driven by the driving force. In the control device of
A remaining capacity detector for detecting a remaining capacity of a secondary battery that supplies power to the drive motor;
A mode switching unit that switches the travel mode from the first travel mode to the second travel mode when the remaining capacity is less than a predetermined determination threshold;
A start-time determination threshold value setting unit that sets a start-time determination threshold value used for determination at the time of start of the vehicle by the mode switching unit; and
A vehicle control device comprising:   2. The vehicle control device according to claim 1, wherein the start-time determination threshold value setting unit sets the start-time determination threshold value based on an average temperature at the time of start-up for a predetermined period.   3. The vehicle determination threshold value according to claim 2, wherein the start-time determination threshold value setting unit sets the start-time determination threshold value based on a difference between a measured value of an outside air temperature measured when the vehicle is started and the average temperature. Control device.   The start time determination threshold setting unit includes at least one information of a total travel distance, a total travel time, a charge / discharge integrated time from the start of use of the secondary battery, or an elapsed number of days after the secondary battery is manufactured. The vehicle control device according to claim 1, wherein the start-time determination threshold value is corrected based on the vehicle start-time determination threshold value.   The vehicle control device according to any one of claims 1 to 4, wherein the mode switching unit performs determination using a determination threshold for traveling after the vehicle is started.   The said mode switching part switches the driving mode from the said 2nd driving mode to the said 1st driving mode only when the said secondary battery is charged by the external charging device. The vehicle control device described in 1. A control device according to any one of claims 1 to 6;
A drive motor for driving the vehicle;
A secondary battery for supplying power to the drive motor;
A power generator for generating electric power to be supplied to at least one of the drive motor and the secondary battery;
A vehicle comprising: A vehicle control device capable of switching between a first travel mode for traveling by the driving force of the drive motor while the auxiliary power generating device is stopped and a second travel mode for traveling by the driving force of the auxiliary power generating device. In
A remaining capacity detector for detecting a remaining capacity of a secondary battery that supplies power to the drive motor;
A mode switching unit that switches the travel mode from the first travel mode to the second travel mode when the remaining capacity is less than a predetermined determination threshold;
A start-time determination threshold value setting unit that sets a start-time determination threshold value used for determination at the time of start of the vehicle by the mode switching unit; and
A vehicle control device comprising: A control device according to claim 8;
A drive motor for driving the vehicle;
A secondary battery for supplying power to the drive motor;
Auxiliary power generator for generating the driving force of the vehicle separately from the drive motor;
A vehicle comprising:

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