JP5454796B2 - Vehicle control device - Google Patents

Description

  The present invention relates to a vehicle control device.

  2. Description of the Related Art Conventionally, development and practical use of hybrid vehicles in which a driving force of a vehicle is obtained by combining an internal combustion engine (engine) and a motor have been progressing. The hybrid vehicle has an EV mode in which driving wheels are driven using only the motor as a power source, a series mode in which the motor is used as a power source and the engine is used as a power supply source of the motor, or both the engine and the motor are used as the power source. Some parallel modes are switched according to driving conditions.

  When driving a drive wheel using such a motor as a power source, in order to initially drive the motor, it is necessary to supply power from a rechargeable battery (battery) mounted on the vehicle. However, when power is supplied from the battery mounted on the vehicle, if the battery is in a low temperature state, the power that can be output from the rechargeable battery is reduced, which may cause start-up failure and controllability deterioration. .

  For this reason, for example, there is known a battery control device that performs temperature rise by internal heat generation of the battery by controlling charging and discharging of the battery repeatedly at a low temperature (see, for example, Patent Document 1).

JP 2007-28702 A

  However, in the battery control device described above, when the temperature is increased by internal heat generation of the battery by controlling the charge / discharge of the battery, the battery is consumed by the discharge current without checking the state of the battery. It is also conceivable that the desired output cannot be obtained due to insufficient power. Further, in a vehicle having a large battery capacity, a traveling pattern in the EV mode is always used, and the engine may not operate for a long period of time, leading to an engine malfunction.

  Accordingly, an object of the present invention is to solve the above-described problems of the prior art, and provide a vehicle control device that can raise the temperature of a battery in a cold state in accordance with the state of the battery, as well as a long-term engine. The purpose is to prevent malfunctions caused by malfunctions.

Control apparatus for a vehicle of the present invention is mounted on a vehicle, the electric power is discharged and battery internal heat generation, a generator which rotates synchronously with the internal combustion engine, and a battery temperature detection means for detecting a temperature of said battery, said A vehicle speed sensor for detecting the speed of the vehicle, a battery discharge power amount calculating means for calculating a maximum discharge power amount of the battery based on the speed of the vehicle, and a required power required for the vehicle based on the speed of the vehicle A required power amount calculating means for calculating an amount; and when the internal combustion engine is stopped, the temperature of the battery is equal to or lower than a predetermined value, and the required power amount is equal to or lower than a maximum discharge power amount of the battery. And a control means for driving the generator by the discharge power of the battery to rotate the internal combustion engine.

  In the present invention, in view of the state of the battery, discharge current is discharged from the battery, and by operating the generator as a motor by the discharged electric power, the battery is heated by internal heat generation, whereby the battery Depending on the state of the battery, it is possible to raise the temperature of the battery when the battery is cold. In addition, since the internal combustion engine is rotated by driving the generator with the discharge power of the battery, it is possible to prevent the internal combustion engine from malfunctioning for a long time.

  Charge state detecting means for detecting the remaining capacity of the battery is further provided, and the control means drives the generator with the discharged power of the battery to drive the internal combustion engine when the remaining capacity is greater than a predetermined threshold. It is preferable to rotate. Thus, since the battery is discharged when the remaining capacity of the battery is greater than or equal to a predetermined amount, it is possible to avoid excessively reducing the state of charge of the battery.

  Preferably, the control means drives the generator with an electric energy that is a difference between the maximum discharge electric energy and the required electric energy to rotate the internal combustion engine. Thus, since the generator is driven by the amount of power that is the difference between the maximum amount of discharged power and the required amount of power, the battery can be discharged with the maximum amount of power, so that the temperature of the battery can be raised efficiently.

  According to the vehicle control apparatus of the present invention, the battery can be heated at a low temperature according to the state of the battery by controlling the generator as a motor and performing discharge control in view of the battery state. In addition, it is possible to avoid malfunctions caused by long-term malfunction of the internal combustion engine.

1 is a schematic diagram of a hybrid vehicle according to a first embodiment. FIG. 2 is a block diagram illustrating a control device according to the first embodiment. It is a figure for demonstrating the discharge control calculation of Embodiment 1. FIG. It is a figure for demonstrating the map used for the discharge control calculation of Embodiment 1. FIG. It is a figure for demonstrating the map used for the discharge control calculation of Embodiment 1. FIG. 3 is a control flowchart of a discharge control unit according to the first embodiment. 3 is a control flowchart of a temperature determination unit according to the first embodiment. 3 is a control flowchart of a discharge determination unit according to the first embodiment. 3 is a control flowchart of the SOC determination unit of the first embodiment. 3 is a timing chart according to the discharge control of the first embodiment. It is a figure for demonstrating the discharge control calculation of Embodiment 2. FIG. 6 is a timing chart according to the discharge control of the second embodiment. FIG. 5 is a partial schematic diagram of a hybrid vehicle according to a third embodiment. It is a graph which shows the relationship between the rotation speed of a generator, and output torque. It is a graph which shows the relationship between the rotation speed of an engine, and load. It is a figure for demonstrating the map used for the discharge control calculation of Embodiment 4. FIG. 6 is a timing chart according to the discharge control of the fourth embodiment.

(Embodiment 1)
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic diagram showing a powertrain configuration of a hybrid vehicle according to an embodiment of the present invention, and FIG. 2 is a block diagram showing a configuration of a control device for the hybrid vehicle.

  As shown in FIG. 1, a hybrid vehicle (hereinafter also simply referred to as “vehicle”) 10 according to the present embodiment includes a front motor 11 and an engine 13 as a driving source for traveling. The driving force of the front motor 11 is transmitted to the front wheels 15 via the front drive transmission mechanism 14. A battery 20, which is a high voltage battery, is connected to the front motor 11 via a front motor inverter 18. Electric power corresponding to the passenger's pedal operation is supplied from the battery 20 to the front motor 11 via the inverter 18. The battery 20 is configured to be able to be charged from an external commercial power source.

  The engine 13 is driven by burning the fuel supplied from the fuel tank 21. A generator 23 is connected to the engine 13 via an output system 22. The generator 23 is driven as the generator 23, and the output system 22 is connected to the generator 23, and is connected to the front drive transmission mechanism 14 via the clutch 24. The generator 23 is connected to the battery 20 via the inverter 18.

  When the engine 13 is driven according to the traveling state of the hybrid vehicle, the driving force of the engine 13 is first transmitted to the generator 23 via the output system 22. That is, the generator 23 is operated by the driving force of the engine 13, and the electric power generated by the generator 23 is appropriately supplied to the front motor 11 and the battery 20. Further, the generator 23 operates as a motor when the battery 20 is discharged in the present embodiment, and the generator 13 consumes a discharge current to operate the engine 13.

  When the clutch 24 is connected in accordance with the traveling state of the vehicle while the engine 13 is driven, the driving force of the engine 13 is transmitted to the front wheels 15 via the front drive transmission mechanism 14.

  That is, the vehicle 10 according to the present embodiment is a so-called hybrid vehicle, and the driving mode is appropriately switched according to the driving situation of the vehicle. As an operation mode, EV mode, series mode, and parallel mode are mentioned, for example.

  In the EV mode, the vehicle is run using only the front motor 11 as a drive source without stopping the supply of fuel to the engine 13 and driving the engine. In the series mode, the front motor 11 is used as a drive source and the engine 13 is used as a power supply source for the front motor 11. That is, the clutch 24 is disengaged and power is not transmitted between the output system and the front drive transmission mechanism, and the driving force of the engine 13 is transmitted only to the generator 23. In the parallel mode, the vehicle is driven using both the front motor 11 and the engine 13 as drive sources. For example, the clutch 24 is connected and the driving force of the engine 13 is transmitted to the front drive transmission mechanism 14 when a necessary driving output cannot be obtained with the driving force of the front motor 11 during high-speed traveling or the like. That is, in the parallel mode, the driving force of the engine 13 is added to the driving force of the front motor 11 (or the driving force of the engine 13 alone) to drive the vehicle.

  Next, the configuration of the control device mounted on such a hybrid vehicle 10 will be described.

  As shown in FIG. 2, the hybrid vehicle 10 includes a control unit 30. The control means 30 includes a temperature determination unit 31, a charge determination unit 32, an SOC determination unit 33, and a charge control unit 34. The SOC determination unit 33 includes a charge state detection unit 33 '. The charging control unit 34 includes a required power amount calculating unit 34a and a maximum power amount calculating unit 34b.

  For example, when the battery 20 is in a cold state and can be discharged, the discharge control unit 34 performs control so that a discharge current is sent from the battery 20 at the start. In the present embodiment, the discharge current flows through the battery 20 due to the discharge of the battery 20 to warm up (heat up) the battery 20 and the temperature of the battery 20 rises. As a result, the battery 20 obtains a desired output. be able to.

  The discharge control unit 34 determines whether or not the battery 20 is in a cold state, that is, whether or not the battery 20 is at a low temperature, based on whether or not the flag indicating that the temperature determination unit 31 is at a low temperature is on. In addition, the discharge control unit 34 turns on a flag indicating whether the battery 20 is in a dischargeable state, the discharge determination unit 32 being in a chargeable state when the load applied to the vehicle is equal to or less than a predetermined amount. Further, the SOC determination unit 33 determines whether the flag indicating that the SOC (State of Charge, state of charge) of the battery 20 is high is set. When these flags are set, the discharge control unit 34 calculates a required power amount (normal power) required for the vehicle based on the running state of the vehicle, and the normal power is charged / discharged of the battery 20. If it is less than the maximum possible power amount (dischargeable power), a flag indicating that is set. When all these flags are set, the discharge control unit 34 determines that the battery 20 is at a low temperature and is in a state where the battery 20 can be discharged, and a discharge current is sent from the battery 20. The generator 23 is controlled so as to be discharged (discharged from the battery 20).

  Each determination unit will be described in detail below.

  The temperature determination unit 31 acquires the temperature of the battery 20 from a temperature sensor 41 provided in the battery 20. The temperature determination unit 31 compares the acquired temperature of the battery 20 with the temperature threshold T1, and when the acquired temperature of the battery 20 is equal to or lower than the temperature threshold T1, the temperature determination flag indicating that the temperature is equal to or lower than the threshold is turned on. Set. If it is greater than the temperature threshold T1, the temperature determination flag is set to OFF. The temperature threshold T1 is a temperature at which the battery 20 is not able to obtain desired output characteristics.

  The discharge determination unit 32 determines whether or not the load applied to the battery 20 is equal to or greater than the load threshold in order to determine whether or not the battery 20 is in a dischargeable state. For example, the discharge determination unit 32 acquires the load information of the battery 20 from the control state of the electric load system of the integrated control unit that performs integrated control of the entire vehicle in the control unit 30, and detects the load state. And the discharge determination part 32 sets the discharge determination flag which shows that it is more than the load threshold value L1 to ON, when this load L of the battery 20 is more than the load threshold value L1. This is because, for example, when the load is small, such as when the vehicle is decelerating and decelerating while the vehicle is decelerating, the battery 20 has an effect of increasing the temperature by the charging current due to the regenerative power.

  The SOC determination unit 33 determines whether the SOC of the battery 20 is larger or smaller than a predetermined threshold value in order to determine whether the battery 20 is in a dischargeable state. That is, since the SOC determination unit 33 cannot discharge when the SOC is low, the SOC determination unit 33 determines whether the SOC is equal to or greater than a threshold value. The state-of-charge detection means 33 ′ provided in the SOC determination unit 33 is based on the voltage information detected by the voltage sensor 42 provided in the battery 20 and the current information detected by the current sensor 43. 20 SOCs are calculated. When the calculated SOC is equal to or greater than the first threshold C1, the SOC determination unit 33 sets the SOC determination flag indicating that the calculated SOC is equal to or greater than the first threshold C1 to ON. The SOC determination unit 33 sets the SOC determination flag to OFF when the SOC is equal to or less than the second threshold C2 (C2 <C1).

  When the control is started, the discharge control unit 34 determines whether the flag is turned on by the temperature determination unit 31, the discharge determination unit 32, and the SOC determination unit 33, and all the flags are set to on. For example, the required power amount calculation means 34a calculates the required power amount (normal power) required for the vehicle based on the running state of the vehicle, and the maximum power amount calculation means 34b calculates the maximum power amount (dischargeable) of the battery 20. When the normal power is smaller than the dischargeable power, the discharge control for the battery 20 is started.

  The discharge control for the battery 20 will be described with reference to FIG. FIG. 3 is a diagram for explaining the calculation contents performed by the discharge control unit 34 (see FIG. 2) in the discharge control. The discharge control unit 34 normally sets the discharge power set according to the vehicle speed and the state of the battery 20. The target discharge power is set by adding to the power, and the output torque of the generator 23 is set so that the target discharge power can be sent from the battery 20 (see FIG. 2). That is, the output torque of the generator 23 here is an output torque when the generator 23 operates as a motor.

  Specifically, the discharge controller 34 uses the map shown in FIG. 4 to determine the current vehicle speed from the vehicle speed detected from the vehicle speed sensor 44 (see FIG. 2) provided in the engine 13 as shown in FIG. The maximum discharge power is derived. As shown in FIG. 4, the maximum discharge power increases stepwise according to the vehicle speed. That is, when the vehicle speed is high, the load becomes large and more discharge power is required. Therefore, the maximum discharge power, which is the maximum value of the power discharged to maintain the vehicle speed, becomes high. By using such a map, it is possible to easily set the maximum discharge power that does not hinder hybrid travel from the current vehicle speed.

  Further, as shown in FIG. 3, the discharge control unit 34 can discharge electric power based on the performance of the battery 20 from the upper limit current value of the battery 20, the current value flowing through the battery 20, and the voltage value applied to the battery 20 ( The dischargeable power is derived. That is, the maximum discharge power that can be discharged from the battery 20 is derived with reference to the performance of the battery 20 and the current state of the battery 20, and by defining the dischargeable power based on the performance of the battery 20 in this way. The discharge current exceeding the dischargeable amount from the battery 20 can be prevented from being sent out.

  The discharge controller 34 selects the smaller value of the derived maximum discharge power and dischargeable power. That is, the smaller one of the values of the maximum discharge power and the dischargeable power is selected so that the maximum discharge power does not exceed the dischargeable power. Then, when this control is not performed, that is, when the selected discharge power is not performed, that is, by adding to the normal power that is the charge / discharge power of the battery 20 set based on the request of the vehicle driver, a desired output is obtained. A target discharge power that can be obtained is derived.

  The discharge control unit 34 derives a target rotational speed when the motor of the generator 23 (see FIG. 2) is operated from the target discharge power at which the desired output can be obtained, using the map shown in FIG. As shown in FIG. 5, the greater the discharge power, the greater the rotational speed of the generator 23 when the motor is operating.

  In the discharge control shown in FIG. 3, the discharge control unit 34 is configured so that the generator 23 can function as a motor at the target rotational speed derived from the map shown in FIG. 5 to form a desired discharge current from the battery 20. The output torque of the generator 23 is derived from the target rotational speed of the generator 23 and the actual rotational speed of the generator 23 obtained by the rotational speed sensor 45 (see FIG. 1) provided in the generator 23.

  The discharge controller 34 outputs a signal to the generator 23 so that the output torque of the generator 23 derived in this way is obtained. As a result, the generator 23 is driven as a motor with a desired output torque, and a discharge current as a desired discharge power is sent from the battery 20. The generator is driven by the discharge current, and the engine is driven. As a result of the discharge current being sent, the temperature of the battery 20 is raised, and the charge / discharge current can be supplied to the front motor 11 (see FIG. 1) with a desired output.

  In the present embodiment, not only the battery 20 is discharged as described above to raise the temperature of the battery 20, but also the deterioration of the engine 13 can be suppressed. That is, when the generator 23 is driven as a motor in discharging the battery 20, the synchronized engine 13 is driven as the generator 23 is driven. By this driving, the engine oil can be circulated in the engine 13, so that deterioration of the engine can be suppressed. Normally, in a hybrid vehicle, if the EV mode continues to travel, the engine is driven less and the engine oil is less likely to circulate in the engine, so the engine may be easily deteriorated. However, in the hybrid vehicle of the present embodiment, the engine 13 is driven by operating the generator 23 during the discharge control, so that the engine 13 is placed on the sliding portion of the engine 13 even if traveling in the EV mode continues. Oil supply can be maintained. As a result, deterioration of the engine 13 can be suppressed.

  Hereinafter, the operation of the control means 30 of the present embodiment will be described based on a control flowchart.

  As shown in FIG. 6, when the control is started, first, in step S1, the discharge control unit 34 sets the temperature determination flag to ON in the temperature determination unit 31, that is, the temperature of the battery 20 is equal to or lower than the temperature threshold T1. It is determined whether or not it is indicated. Note that this control is performed every predetermined time immediately after the vehicle is started and traveling in the EV mode, but is not executed after the temperature determination flag is set to OFF. When the temperature determination flag is set to ON in the temperature determination unit 31 (YES), the process proceeds to step S2. If the temperature determination flag is not set to ON in the temperature determination unit 31 (NO), the process ends.

  The setting of the temperature determination flag in step S1 will be described in detail with reference to FIG. As shown in FIG. 7, first, in step S11, the temperature determination unit 31 compares the temperature information T acquired from the temperature sensor 41 provided in the battery 20 with the temperature threshold value T1. When the acquired temperature of the battery 20 is equal to or lower than the temperature threshold T1 (YES), the process proceeds to step S12, and the temperature determination unit 31 sets the temperature determination flag to ON. When it is larger than the temperature threshold T1 (NO), the process proceeds to step S13, and the temperature determination unit 31 sets the temperature determination flag to OFF. The discharge control unit 34 determines whether or not the temperature determination unit 31 has turned on the temperature determination flag in step S1.

  Returning to FIG. 6, in step S <b> 2, the discharge control unit 34 determines whether or not the discharge determination flag is set to ON in the discharge determination unit 32. When the discharge determination flag is set to ON (YES), the process proceeds to step S3. If the discharge determination flag is set to OFF (NO), the process ends.

  The setting of the discharge determination flag in step S2 will be described in detail with reference to FIG. First, in step S21, the discharge determination unit 32 acquires the load L of the battery 20, and compares the load L of the battery 20 with the load threshold L1. If the load L of the battery 20 is equal to or greater than the load threshold L1 (YES), the discharge determination flag is set to ON. When the load L of the battery 20 is smaller than the load threshold L1, the discharge determination flag is set off. In step S2, the discharge control unit 34 determines whether or not the discharge determination unit 32 has the discharge determination flag set to ON.

  Returning to FIG. 6, in step S <b> 3, the discharge control unit 34 determines whether the SOC determination flag is on in the SOC determination unit 33. When the SOC determination flag is on (YES), the process proceeds to step S4. If the SOC determination flag is off (NO), the process ends.

  The setting of the SOC determination flag in step S3 will be described in detail with reference to FIG. First, in step S31, the SOC determination unit 33 determines whether or not the SOC determination flag is already set off. If the SOC determination flag is set to OFF, the process proceeds to step S32. If the SOC determination flag is set to ON, the process proceeds to step S33.

  In step S32, it is determined whether or not the current SOC of the battery 20 derived from the map is greater than or equal to the first threshold C1. When the SOC is greater than or equal to the first threshold C1 (YES), the process proceeds to step S34. If the SOC is smaller than the first threshold C1 (NO), the process ends. That is, in this state, the SOC determination flag is kept off.

  In step S33, it is determined whether or not the current SOC of the battery 20 derived from the map is equal to or less than the second threshold value C2. When the SOC is equal to or less than the second threshold C2 (YES), the process proceeds to step S35. If the SOC is greater than the second threshold C2 (NO), the process ends. In this state, the SOC determination flag is kept on.

  In step S34, since the SOC is equal to or greater than the first threshold C1, the SOC determination flag is set to ON, and the process ends. In step S35, since the SOC is equal to or smaller than the second threshold value C2, the SOC determination flag is set to OFF, and the process ends. The discharge controller 34 determines whether or not this SOC determination flag is set to ON in step S3.

  Returning to FIG. 6, in step S4, since all the flags are set to ON, that is, the battery 20 is in a cold state and the battery 20 is in a dischargeable state, the discharge control unit 34 The required power amount calculating means 34a calculates the required power amount (normal power) required for the vehicle based on the running state of the vehicle, and the maximum power amount calculating means 34b calculates the maximum power amount (dischargeable power) of the battery 20. Is calculated. If the normal power is smaller than the dischargeable power (YES), the process proceeds to step S5. If the normal power is greater than the dischargeable power, the process ends. In step S5, the output torque of the generator 23 is derived so that a desired discharge current can be delivered from the battery 20. The process is thus completed, and the generator 23 is driven as a motor with the desired output torque derived, and a desired discharge current is sent from the battery 20. Thereby, the battery 20 is heated.

  The discharge current when controlled in this way will be described with reference to the timing chart shown in FIG. In FIG. 10, the charging / discharging current to the battery 20 when the main control is performed is indicated by a solid line, and the charging / discharging current (normal current) to the battery 20 when the main control is not performed as a comparison is indicated by a dotted line. Yes.

  Since the battery 20 is in the cold state and can be discharged to raise the temperature of the battery 20 between the times t1 and t2 when starting, the temperature determination flag, the discharge determination flag, and the SOC determination flag are set. All are on. At this time, a larger amount of discharge current is always sent by the amount of discharge power (+ α) than the normal current when the main control by the discharge control unit 34 is not performed.

  Next, between times t2 and t3, the discharge determination flag is off, the discharge control is not performed, and the battery 20 is charged and discharged with the same charge / discharge current as the normal current.

  Between times t3 and t4, the battery 20 is still in a cold state and can be discharged to raise the temperature of the battery 20, so that the temperature determination flag, the discharge determination flag, and the SOC determination flag are all on. It has become. At this time, a larger amount of discharge current always flows than the normal current when the main control by the discharge control unit 34 is not performed, by the amount of discharge power (+ α).

  Next, between time t4 and t5, the SOC determination flag is turned off first, and then the discharge determination flag is turned off. Therefore, the discharge control is not performed, and the battery 20 has the same charge / discharge current as the normal current. Is flowing. Specifically, since the discharge control continued until time t4, the SOC becomes equal to or lower than the second threshold C2 at time t4, the SOC determination flag is turned off, and the charge / discharge current follows the normal current. Thereafter, at time t4a, the high voltage load is reduced, the discharge determination flag is turned off, and the normal current starts charging. The charge / discharge current follows the normal current. Next, at time t4b, as the charging continues, the SOC becomes equal to or higher than the first threshold C1 and the SOC determination flag is turned on. However, since the discharge determination flag is still off, the charge / discharge current follows the normal current. . Thereafter, at time t5, the high voltage load becomes large and the discharge determination flag is turned on, whereby all the flags are turned on.

  Next, during the times t5 to t6, the temperature determination flag, the discharge determination flag, and the SOC determination flag are all on. At this time, a larger amount of discharge current always flows than the normal current when the main control by the discharge control unit 34 is not performed, by the amount of discharge power (+ α).

  Thereafter, after time t6, the temperature determination flag is turned off, and thus this control is terminated. As described above, in this embodiment, the battery 20 is discharged so as not to affect the state of charge of the battery 20 when the predetermined requirement is satisfied without repeating charging and discharging in order to raise the temperature of the battery 20. The battery 20 can be heated. Thereby, the electric power of the battery 20 is not consumed due to the temperature rise of the battery 20 and becomes insufficient.

  In the timing chart shown in FIG. 10, the maximum discharge power is always constant because the vehicle speed is substantially constant. However, depending on the vehicle speed, the maximum discharge power varies as described above. There is a possibility that the discharge current value (+ α), which was constant in the present embodiment, varies.

  Thus, in this embodiment, if the temperature of the battery 20 is lower than the threshold value, it is determined whether or not the battery 20 is in a dischargeable state and discharge control is performed to raise the temperature of the battery 20. . As a result, the generator 23 can be driven in accordance with the state of charge of the battery 20 to perform discharge control, so that the temperature can be raised immediately and a desired output can be achieved without impeding the travel of the hybrid vehicle 10. It is possible to obtain

(Embodiment 2)
Another embodiment of the present invention will be described. In the present embodiment, unlike the first embodiment, as shown in FIG. 11, the discharge control unit 34 (see FIG. 2) does not acquire the vehicle speed from the vehicle speed sensor and does not derive the maximum discharge power. Further, the difference from Embodiment 1 is that the difference between the dischargeable power and the normal power is set as the target discharge power. In other words, the discharge control unit 34 controls the discharge current so that a discharge current corresponding to the chargeable power of the battery 20 always flows during the discharge control. By controlling in this way, unlike the first embodiment, the discharge control unit 34 increases the temperature of the battery 20 earlier than the first embodiment because a discharge current corresponding to the chargeable power always flows regardless of the vehicle speed. It is possible.

  Specifically, the discharge control unit 34 acquires the dischargeable power from the upper limit current value of the battery 20, the battery current value flowing through the current battery, and the battery voltage value applied to the current battery 20. The difference between the dischargeable power and the normal power is set as the target discharge power. Then, the generator output torque is derived from this target discharge power in the same manner as in the first embodiment.

  In this case, the discharge current is discharged from the battery 20 as shown in the timing chart of FIG. In FIG. 12, the charging / discharging current to the battery 20 when this control is performed is indicated by a dotted line (one-dot chain line), and the charging / discharging current (normal current) to the battery 20 when this control is not performed as a comparison is a dotted line. It is described by (two-dot chain line).

  Since the battery 20 is in a cold state and can be charged for increasing the temperature of the battery 20 between the times t1 and t2, which is the start time, the temperature determination flag, the discharge determination flag, and the SOC determination flag are set. All are on. At this time, a discharge current based on the difference between the normal power and the dischargeable power flows.

  Next, between times t2 and t3, since the discharge determination flag is off, the discharge control is not performed, and the same charge / discharge current as the normal current flows through the battery 20.

  Next, between time t3 and t4 ′ (t4 ′ <t4), the battery 20 is still in a cold state and can be discharged to raise the temperature of the battery 20, so that the temperature determination flag, discharge The determination flag and the SOC determination flag are all on. At this time, the discharge current flows by the difference (+ α) between the normal current and the dischargeable power when the main control by the discharge control unit 34 is not performed. Then, when the discharge current is sufficiently sent from the battery 20, the temperature of the battery 20 is raised, and the temperature determination flag is turned off at time t4 '. Thereby, this control is completed.

  That is, in the present embodiment, unlike the first embodiment, the generator is driven by the power amount that is the difference between the maximum discharge power amount and the required power amount, so that the battery can be discharged at the maximum power amount that can be discharged, The temperature of the battery can be raised efficiently. It should be noted that the amount of power that is the difference between the maximum discharge power amount and the required power amount may not be the maximum value of this difference.

(Embodiment 3)
In the present embodiment, as shown in FIG. 13, unlike the first embodiment shown in FIG. 1, a speed reducer 25 is provided between the generator 23 and the engine 13. By providing the speed reducer 25 in this way, the engine speed can be suppressed while maintaining the power consumption in the generator 23. This point will be described with reference to FIGS. 14 and 15.

  In FIG. 14, the relationship between the rotation speed at the time of motor operation of the generator 23 and output torque is shown. FIG. 15 shows the relationship between the rotational speed of the engine 13 and the load. As shown in FIG. 14, the operating point moves from a high efficiency region to a low region by increasing the number of revolutions of the generator. In other words, the operating point indicated by ○ in the figure exists in the high efficiency region, but by moving the rotational speed, it moves to the operating point existing in the low efficiency region indicated by ● in the figure. To do. Thus, if it moves to the operation point with low efficiency, the power consumption of the generator 23 can be increased. On the other hand, as indicated by a solid line in FIG. 15, when the engine 13 has a higher rotational speed, the resistance increases and the engine load increases.

  Accordingly, when the rotational speed of the generator 23 is increased, the rotational speed of the engine 13 synchronized therewith is also increased, and as a result, the engine load increases. That is, if the rotational speed of the generator 23 is increased in order to increase the discharge current from the battery 20, the engine load increases.

  Therefore, in the present embodiment, as shown in FIG. 13, a speed reducer 25 is provided between the generator 23 and the engine 13. Thereby, the engine load can be suppressed while maintaining the power consumption in the generator 23, that is, the rotation speed. That is, even if the rotational speed of the generator 23 is increased in order to ensure the power consumption of the generator 23, the increase in the rotational speed of the engine 13 can be suppressed by the speed reducer 25.

  Therefore, in this embodiment, even when it is desired to suppress the engine speed, for example, when the engine has not been operated for a long period of time, the speed of the engine 13 can be reduced while maintaining the power consumption in the generator 23.

  As described above, in the first to third embodiments, the discharge current from the battery 20 is controlled by driving the engine 13 by the control unit 30 in consideration of the state of the battery 20 and driving the generator 23 as a motor. The temperature of the battery 20 can be increased without running out of the battery 20, and as a result, a desired output can be obtained from the battery 20. In addition to discharging the battery 20 in this way to raise the temperature of the battery 20, the engine 13 can be driven to circulate the engine oil by driving the generator 23 as a motor. 13 deterioration can be suppressed. In the first embodiment, since the discharge current can be controlled based on the traveling state of the vehicle, the traveling of the vehicle is not hindered. Further, in the second embodiment, the battery 20 can be configured to obtain a desired output earlier by raising the temperature earlier. Furthermore, in the third embodiment, by providing the speed reducer 25, it is possible to control the discharge current so as to suppress the engine speed while maintaining the power consumption in the generator 23, thereby suppressing the engine speed. It is effective when you want to.

(Embodiment 4)
Still another embodiment of the present invention will be described. In the present embodiment, the discharge control is different from that in the first embodiment, and the maximum power amount calculation means 34 ′ provided in the discharge control unit 34 (see FIG. 2) includes vehicle speed information detected by the vehicle speed sensor 44 shown in FIG. Based on the above, the maximum discharge power is derived. In this case, the maximum power amount calculation means 34 ′ derives the maximum discharge power using the map shown in FIG. In the map shown in FIG. 16, the maximum discharge power continuously changes in proportion to the vehicle speed. That is, the maximum discharge power increases as the vehicle speed increases. In this case, since the maximum discharge power can be obtained according to the traveling state of the vehicle, that is, the load state, it is possible to easily set the maximum discharge power that does not hinder the hybrid traveling.

  In this case, the discharge current is supplied to the battery 20 as shown in the timing chart of FIG. In FIG. 17, the charging / discharging current to the battery 20 when the main control is performed is indicated by a solid line, and the charging / discharging current (normal current) to the battery 20 when the main control is not performed as a comparison is indicated by a dotted line. Yes.

  Since the battery 20 is in a cold state and can be discharged for warm-up of the battery 20 between times t1 and t2, which is a start time, the temperature determination flag, the discharge determination flag, and the SOC determination flag are set. All are on. At this time, a larger amount of discharge current always flows than the normal current when the main control by the discharge control unit 34 is not performed, by the amount of discharge power (+ α). The discharge current in this case is constant because the vehicle speed is constant between times t1 and t2.

  Next, between times t2 and t3, the discharge determination flag is off, the discharge control is not performed, and the battery 20 is charged and discharged with the same charge / discharge current as the normal current.

  Between times t3 and t4, the battery 20 is still in a cold state and can be discharged to warm up the battery 20, so that the temperature determination flag, the discharge determination flag, and the SOC determination flag are all on. It has become. At this time, a larger amount of discharge current always flows by the amount of discharge power (+ α on the discharge side) than the normal current when the main control by the discharge control unit 34 is not performed. The amount of + α of the discharge current between times t3 and t4 increases between times t3a and t4 in proportion to the increase in vehicle speed between times t3a and t4. As a result, the discharge current flows by + α more than the normal current, but this value also increases or decreases according to the vehicle speed.

  Next, between time t4 and t5, the SOC determination flag is turned off first, and then the discharge determination flag is turned off. Therefore, the discharge control is not performed, and the battery 20 has the same charge / discharge current as the normal current. Is flowing. Specifically, since the discharge control continued until time t4, the SOC becomes equal to or lower than the second threshold at time t4, the SOC determination flag is turned off, and the charge / discharge current follows the normal current. Thereafter, at time t4a, the high voltage load is reduced and the discharge determination flag is turned off. The charge / discharge current still follows the normal current. Next, at time t4b, since the discharge has continued, the SOC becomes the first threshold C1 or more and the SOC determination flag is turned on. However, since the discharge determination flag is still off, the charge / discharge current follows the normal current. . Thereafter, at time t5, the high voltage load becomes large and the discharge determination flag is turned on, whereby all the flags are turned on.

  Next, during the times t5 to t6, the temperature determination flag, the discharge determination flag, and the SOC determination flag are all on. At this time, a larger amount of discharge current always flows than the normal current when the main control by the discharge control unit 34 is not performed, by the amount of discharge power (+ α). However, in this case, since the maximum discharge power exceeds the dischargeable power from time t5 to time t5a, the discharge current is controlled to be dischargeable power. Thereafter, from time t5a to t6, the maximum discharge current becomes smaller in proportion to the increase in the vehicle speed and becomes smaller than the dischargeable power. Therefore, the maximum discharge current becomes the target discharge power, and the discharge current flows based on this. It was.

  Thereafter, after time t6, the temperature determination flag is turned off, and thus this control is terminated. As described above, in the present embodiment, the charging of the battery 20 is not performed repeatedly, and only discharging is performed when a predetermined requirement is satisfied without repeating charging / discharging. It will not be consumed by the machine.

  In the present embodiment, since an appropriate discharge current can be obtained according to the vehicle speed, that is, the running state of the vehicle, the battery 20 can be warmed up and desired power can be supplied without disturbing the hybrid running. become.

  The present invention is not limited to the embodiments described above. In the first embodiment, the control is performed in the order of steps S1 to S3. However, for example, the control can be performed in the order of step S1, step S3, and step S2. For example, in the first and fourth embodiments, the difference between the dischargeable power and the normal power may be the discharge power.

  Further, for example, in each of the above-described embodiments, the negative pressure system of the engine 13 and the negative pressure system of the brake may be the same. With this configuration, the generator 23 can be driven as a motor in the discharge control, and the engine 13 can be driven to generate a negative pressure. In this case, if the negative pressure system of the engine 13 and the negative pressure system of the brake are made the same, the brake negative pressure can be generated without using the negative pressure pump. As a result, the driving frequency of the negative pressure pump can be suppressed.

  Of the above-described embodiments, in Embodiment 2, the difference power between the normal current and the dischargeable power is set as the target discharge power. However, the present invention is not limited to this. It is good. Thus, when all of the temperature determination flag, the discharge determination flag, and the SOC determination flag are on, the current corresponding to the dischargeable power is always sent from the battery 20 earlier than in the case of the first embodiment. The battery 20 can be heated to supply desired power.

  The vehicle control device of the present invention can be used, for example, in the vehicle manufacturing industry.

  DESCRIPTION OF SYMBOLS 10 Hybrid vehicle, 13 Engine, 20 Battery, 23 Generator, 30 Control means 31 Temperature determination part, 32 Discharge determination part, 33 SOC determination part, 34 Charge control part, 41 Temperature sensor, 42 Voltage sensor, 43 Current sensor, 44 Vehicle speed sensor, 45 rpm sensor

Claims (3)

A battery that is mounted on a vehicle and generates heat internally when power is discharged,
A generator that rotates synchronously with the internal combustion engine;
Battery temperature detecting means for detecting the temperature of the battery;
A vehicle speed sensor for detecting the speed of the vehicle;
Battery discharge energy calculation means for calculating the maximum discharge energy of the battery based on the speed of the vehicle ;
A required power amount calculating means for calculating a required power amount required for the vehicle based on the speed of the vehicle;
When the internal combustion engine is stopped, the temperature of the battery is equal to or lower than a predetermined value, and the required power amount is equal to or lower than the maximum discharge power amount of the battery, the generator is driven by the discharge power of the battery. And a control means for driving and rotating the internal combustion engine. A charge state detecting means for detecting a remaining capacity of the battery;
2. The vehicle control according to claim 1, wherein, when the remaining capacity is larger than a predetermined threshold value, the control unit drives the generator by the discharge power of the battery to rotate the internal combustion engine. apparatus.   3. The vehicle according to claim 1, wherein the control unit rotates the internal combustion engine by driving the generator with an amount of electric power that is a difference between the maximum amount of discharged electric power and the required amount of electric power. Control device.

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