JP6606444B2 - Vehicle control device - Google Patents

Description

  The present invention relates to a vehicle control device that controls a generator connected to an engine.

  A generator such as a motor generator, an alternator, or an integrated starter generator (ISG) is connected to an engine mounted on the vehicle. A generator connected to an engine is not only driven to generate power by engine power, but is also controlled to a power generation state during vehicle braking or coasting from the viewpoint of improving fuel efficiency of the vehicle (Patent Document 1). To 3). By the way, controlling the generator to the power generation state is a factor for decelerating the vehicle by the power generation torque. For this reason, when controlling a generator to an electric power generation state, it is calculated | required to control the electric power generation torque of a generator appropriately so that a passenger | crew may not be discomforted.

Japanese Patent Laid-Open No. 2015-116085 International Publication No. 2012/090924 International Publication No. 2012/063572

  By the way, in order to appropriately control the power generation torque of the generator, it is necessary to set the power generation torque of the generator that is allowed for every traveling situation, that is, to construct complicated map data. However, the construction of complex map data has been a factor that increases the cost of the vehicle control device that controls the generator.

  An object of the present invention is to reduce the cost of a vehicle control device that controls a generator.

  A vehicle control device according to the present invention is a vehicle control device that controls a generator connected to an engine, and based on the allowable deceleration of the vehicle during coasting, the vehicle deceleration reaches the allowable deceleration. A first power calculation unit that calculates a first deceleration power for causing the vehicle to travel, and a second work that calculates a second deceleration power corresponding to a travel resistance that decelerates the vehicle based on the travel speed of the vehicle during coasting. Based on a rate calculation unit, an upper limit power calculation unit that subtracts the second deceleration power from the first deceleration power, and calculates an upper limit power of the generator, and the upper limit power of the generator An upper limit torque calculating unit that calculates an upper limit torque of the generator, and a generator control unit that limits the generated torque of the generator during coasting based on the upper limit torque.

  According to the present invention, by limiting the power generation torque during coasting by the upper limit torque, the power generation torque of the generator can be appropriately controlled, and the vehicle deceleration during coasting can be suppressed to an allowable deceleration or less. Can do. In addition, by calculating the upper limit torque using the power, it is possible to avoid the construction of complicated map data, so that the cost of the vehicle control device that controls the generator can be reduced.

It is the schematic which shows the structural example of the vehicle provided with the control apparatus for vehicles which is one embodiment of this invention. It is a circuit diagram which shows an example of a power supply circuit. It is the schematic which shows the control system of the control apparatus for vehicles. (A) is a figure which shows the electric power supply condition when controlling a motor generator to an electric power generation state, (b) is a figure which shows the electric power supply condition when controlling a motor generator to an electric power generation halt state. It is a block diagram which shows an example of each function part with which the control unit which performs regenerative power generation control is provided. It is a block diagram which shows an example of each function part with which the control unit which performs regenerative power generation control is provided. It is a timing chart which shows an example of transition of vehicle body deceleration at the time of coast running. It is a flowchart which shows an example of the execution procedure of regenerative power generation control. It is a block diagram which shows an example of the control unit which comprises the vehicle control apparatus which is other embodiment of this invention. (A)-(d) is a figure which shows an example of transition of a vehicle body deceleration change rate. (A) And (b) is a figure which shows an example of the calculation procedure of ideal vehicle body deceleration. It is a timing chart which shows an example of transition of vehicle body deceleration at the time of coast running.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic diagram showing a configuration example of a vehicle 11 including a vehicle control device 10 according to an embodiment of the present invention. As shown in FIG. 1, a power unit 13 including an engine 12 is mounted on the vehicle 11. A motor generator (generator) 16 is connected to the crankshaft 14 of the engine 12 via a belt mechanism 15. Further, a transmission mechanism 18 is connected to the engine 12 via a torque converter 17, and wheels 20 are connected to the transmission mechanism 18 via a differential mechanism 19 and the like. Further, the power unit 13 is provided with a starter motor 21 for starting and rotating the crankshaft 14. The engine 12 is connected to an engine controller 23 composed of a computer or the like in order to control an engine accessory 22 such as an injector, an igniter and a throttle valve.

  The motor generator 16 connected to the engine 12 is a so-called ISG (integrated starter generator) that functions as a generator and an electric motor. The motor generator 16 not only functions as a generator driven by the crankshaft 14, but also functions as an electric motor that starts and rotates the crankshaft 14 in so-called idling stop control. The motor generator 16 has a stator 30 provided with a stator coil and a rotor 31 provided with a field coil. Further, the motor generator 16 is provided with an ISG controller 32 including an inverter, a regulator, a computer and the like in order to control the energization state of the stator coil and the field coil. By controlling the energization state of the field coil and the stator coil by the ISG controller 32, the power generation torque or the like of the motor generator 16 functioning as a generator is controlled, or the drive torque or the like of the motor generator 16 functioning as an electric motor is controlled. be able to.

  Then, the power supply circuit 40 with which the vehicle control apparatus 10 is provided is demonstrated. FIG. 2 is a circuit diagram showing an example of the power supply circuit 40. As shown in FIG. 2, the power supply circuit 40 includes a lithium ion battery 41 and a lead battery 42 connected in parallel thereto. Note that the terminal voltage of the lithium ion battery 41 is designed to be higher than the terminal voltage of the lead battery 42 in order to charge and discharge the lithium ion battery 41 actively. Further, in order to positively charge and discharge the lithium ion battery 41, the internal resistance of the lithium ion battery 41 is designed to be smaller than the internal resistance of the lead battery 42.

  A positive electrode line 43 is connected to the positive electrode terminal 41 a of the lithium ion battery 41, a positive electrode line 44 is connected to the positive electrode terminal 42 a of the lead battery 42, and a positive electrode line 45 is connected to the positive electrode terminal 16 a of the motor generator 16. It is connected. These positive electrode lines 43 to 45 are connected to each other through a connection point 46. A negative electrode line 47 is connected to the negative electrode terminal 41 b of the lithium ion battery 41, a negative electrode line 48 is connected to the negative electrode terminal 42 b of the lead battery 42, and a negative electrode line is connected to the negative electrode terminal 16 b of the motor generator 16. 49 is connected. These negative electrode lines 47 to 49 are connected to the reference potential point 50.

  The negative electrode line 47 connected to the lithium ion battery 41 is provided with a switch SW1 that can be switched between a conduction state and a cutoff state. The positive line 44 connected to the lead battery 42 is provided with a switch SW2 that can be switched between a conduction state and a cutoff state. As shown in FIG. 1, an electrical device 51 such as an electrical component is connected to the positive line 44 positioned downstream of the switch SW <b> 2, and a starter motor 21 is connected via a starter relay 52. The positive electrode line 44 is provided with a fuse 53 that protects the electric device 51 and the like. Further, the power supply circuit 40 of the vehicle control device 10 is provided with a battery module 54 including a lithium ion battery 41 and switches SW1 and SW2. The battery module 54 is provided with a battery controller 55 composed of a computer or the like. The battery controller 55 has a function of monitoring the state of charge, current, voltage, temperature, etc. of the lithium ion battery 41 and a function of controlling the switches SW1, SW2.

[Control System for Vehicle Control Device]
A control system of the vehicle control device 10 will be described. FIG. 3 is a schematic diagram showing a control system of the vehicle control device 10. As shown in FIGS. 1 and 3, the vehicle control device 10 includes a control unit 60 that outputs a control signal to the ISG controller 32 in order to control the power generation voltage, power generation torque, and the like of the motor generator 16. The control unit 60 is connected to the ISG controller 32, the engine controller 23, the battery controller 55, and the like via an in-vehicle network 56 such as CAN or LIN. Such a control unit 60 determines the state of charge SOC of the lithium ion battery 41, the operating state of the engine 12, the operating state of the accelerator pedal, the operating state of the brake pedal, and the like based on information from various controllers and sensors. . The control unit 60 controls charging / discharging of the lithium ion battery 41 by controlling the power generation voltage of the motor generator 16 based on the state of charge SOC of the lithium ion battery 41, the operating state of the engine 12, and the like. . The control unit 60 is configured by a computer system such as a CPU, a ROM, and a RAM.

  As shown in FIG. 3, as sensors connected to the control unit 60, an accelerator sensor 61 that detects an operation state of an accelerator pedal, a brake sensor 62 that detects an operation state of a brake pedal, and a vehicle speed that is a traveling speed of the vehicle. There is a vehicle speed sensor 63 to detect. In addition, information such as the power generation voltage, power generation current, power generation torque, and rotor rotational speed of the motor generator 16 is input from the ISG controller 32 to the control unit 60. Further, information such as the engine speed, the fuel injection amount, and the throttle opening is input from the engine controller 23 to the control unit 60. Furthermore, information such as the state of charge SOC of the lithium ion battery 41, the charge / discharge current, and the terminal voltage is input from the battery controller 55 to the control unit 60. The state of charge (SOC) is the ratio of the amount of stored electricity to the design capacity of the battery.

[Battery charge / discharge control]
Control unit 60 controls charging / discharging of lithium ion battery 41 by controlling motor generator 16 to a power generation state or a power generation halt state based on the charge state SOC of lithium ion battery 41. Here, FIG. 4A is a diagram showing a power supply situation when the motor generator 16 is controlled to the power generation state, and FIG. 4B is a power supply situation when the motor generator 16 is controlled to the power generation halt state. FIG. Note that the power generation state of the motor generator 16 includes a combustion power generation state in which the motor generator 16 is driven to generate power by engine power, and a regenerative power generation state in which the motor generator 16 is driven to generate power when the vehicle is decelerated.

  When the state of charge SOC of the lithium ion battery 41 falls below a predetermined lower limit value, the motor generator 16 is controlled to the combustion power generation state in order to charge the lithium ion battery 41 by the motor generator 16. When the motor generator 16 is controlled to the combustion power generation state, the power generation voltage of the motor generator 16 is raised above the terminal voltage of the lithium ion battery 41. As a result, electric power is supplied from the motor generator 16 to the lithium ion battery 41, the electric device 51, the lead battery 42, and the like as indicated by the black arrows in FIG. The lithium ion battery 41 is charged.

  On the other hand, when the state of charge SOC of the lithium ion battery 41 exceeds a predetermined upper limit value, the motor generator 16 is controlled to the power generation halt state in order to promote the discharge of the lithium ion battery 41 and reduce the engine load. When controlling the motor generator 16 to the power generation halt state, the power generation voltage of the motor generator 16 is lowered from the terminal voltage of the lithium ion battery 41. As a result, as indicated by the solid arrows in FIG. 4B, electric power is supplied from the lithium ion battery 41 to the electric device 51 and the like, so that the power generation of the motor generator 16 can be suppressed, and the engine The load can be reduced. Note that when the motor generator 16 is controlled to the combustion power generation state or the power generation halt state, the switches SW1 and SW2 are held in the conductive state.

  As described above, the motor generator 16 is controlled to the combustion power generation state or the power generation suspension state based on the state of charge SOC. From the viewpoint of improving the fuel efficiency of the vehicle 11, the motor generator 16 is controlled to the regenerative power generation state when the vehicle is decelerated. Is done. Whether or not to perform regenerative power generation of the motor generator 16 is determined based on the operation state of an accelerator pedal or a brake pedal. For example, when the accelerator pedal is released or the brake pedal is depressed, the power generation voltage of the motor generator 16 is raised above the terminal voltage of the lithium ion battery 41, and the motor generator 16 enters the regenerative power generation state. Be controlled.

  By the way, when the motor generator 16 is controlled to be in the regenerative power generation state when the vehicle is decelerated when the accelerator pedal is released, that is, when coasting is performed in which the fuel supply to the engine 12 is cut off, the occupant does not feel uncomfortable. In addition, it is required to control the motor generator 16. That is, in coasting, which is coasting where the vehicle 11 is slowly decelerated, the power generation torque of the motor generator 16, that is, the regenerative torque, has a great influence on the vehicle body deceleration (vehicle deceleration). It is required to control the regenerative torque so as not to decelerate greatly.

[Regenerative power generation control during coasting]
Hereinafter, regenerative power generation control of the motor generator 16 that is executed during coasting will be described. 5 and 6 are block diagrams showing an example of each functional unit provided in the control unit 60 that executes regenerative power generation control. FIG. 7 is a timing chart showing an example of the transition of vehicle body deceleration during coasting. First, as shown in FIG. 5, the control unit 60 includes an ideal deceleration setting unit 70, an ideal power calculation unit 71, a rolling resistance power calculation unit 72, an air resistance power calculation unit 73, and an engine resistance power calculation unit. 74, a regenerative work rate calculation unit 75, and a torque limit value calculation unit 76.

  The ideal deceleration setting unit 70 refers to a predetermined deceleration map based on the vehicle speed V during coasting and sets an ideal vehicle body deceleration Dx that is an allowable deceleration of the vehicle 11. For example, the ideal vehicle body deceleration Dx is set large at high vehicle speeds, while the ideal vehicle body deceleration Dx is set small at low vehicle speeds. A fixed value may be adopted as the ideal vehicle body deceleration Dx. The ideal vehicle body deceleration Dx is a deceleration allowed during coasting from the viewpoint of vehicle quality, and is an upper limit value of the deceleration that does not give a great sense of discomfort to the occupant. In other words, during coasting, the vehicle 11 can be driven without causing a great sense of discomfort to the occupant by limiting the vehicle body deceleration to the ideal vehicle body deceleration Dx or less.

The ideal power calculation unit (first power calculation unit) 71 calculates a vehicle body ideal deceleration power (first deceleration power) P1 from the ideal vehicle deceleration Dx based on the following equation (1). The vehicle body ideal deceleration work rate P1 is a work rate necessary for causing the vehicle body deceleration to reach the ideal vehicle body deceleration Dx. That is, the vehicle body deceleration can be increased to the ideal vehicle body deceleration Dx by decelerating the vehicle 11 using energy corresponding to the vehicle body ideal deceleration work rate P1. Note that “Wv” shown in Equation (1) is the vehicle mass.
P1 [W] = Wv [kg] x Dx [m / s ² ] x V [m / s] (1)

The rolling resistance power calculation unit (second power calculation unit) 72 calculates a rolling resistance power (second deceleration power) P2a from the vehicle speed V based on the following equation (2). This rolling resistance power P2a is a power for the running resistance that decelerates the vehicle 11 during coasting. In addition, “μr” shown in Expression (2) is a rolling resistance coefficient, and “g” is a gravitational acceleration.
P2a [W] = μr × Wv [kg] × g [m / s ² ] × V [m / s] (2)

The air resistance power calculation unit (second power calculation unit) 73 calculates the air resistance power (second deceleration power) P2b from the vehicle speed V based on the following equation (3). This air resistance power P2b is a power for the travel resistance that decelerates the vehicle 11 during coasting. In addition, “μl” shown in Expression (3) is an air resistance coefficient, “ρ” is an air density, and “S” is a front projected area of the vehicle 11.
P2b [W] = μl × ρ [kg / m ³ ] × S [m ² ] × {V [m / s]} ³ (3)

The engine resistance power calculation unit (third power calculation unit) 74 calculates an engine friction power (third deceleration power) P3 from the engine speed (engine speed) Ne based on the following equation (4). calculate. The engine friction work rate P3 is a work rate corresponding to an engine rotation resistance that decelerates the vehicle 11 during coasting. “Tef” shown in Expression (4) is an engine friction torque corresponding to the braking torque of the engine brake. Here, the engine friction torque Tef is a sum of engine pumping loss torque, engine mechanical loss torque, and ISG belt friction torque. The engine pumping loss torque is a rotational resistance torque generated in the intake stroke and the exhaust stroke of the engine 12. The engine mechanical loss torque is a torque obtained by subtracting the engine net torque from the engine indicated torque, and is a rotational resistance torque due to a frictional resistance inside the engine. Further, the ISG belt friction torque is a rotational resistance torque due to the rotational resistance of the belt mechanism 15.
P3 [W] ＝ Tef [Nm] × Ne [rad / s] (4)

Based on the following equation (5), the regenerative power calculation unit (upper limit power calculation unit) 75 calculates the rolling resistance power P2a, the air resistance power P2b, and the engine friction power P3 from the vehicle body ideal deceleration power P1. Is subtracted to calculate the deceleration regeneration power (upper limit power) Pg. The deceleration regenerative work rate Pg is a work rate allowed for regenerative power generation during coasting, that is, an upper limit value of a work rate allowed for motor generator 16 during coasting.
Pg [W] = {P1-P2a-P2b-P3 [W]} (5)

The torque limit value calculation unit (upper limit torque calculation unit) 76 divides the deceleration regenerative work rate Pg by the rotational speed Nisg of the motor generator 16 based on the following equation (6) to generate a regenerative torque limit value (upper limit torque) Tg. Is calculated. The regenerative torque limit value Tg is an upper limit value of the regenerative torque allowed for the motor generator 16 during coasting.
Tg [Nm] = Pg [W] / Nisg [rad / s] (6)

  Thus, the regenerative torque limit value Tg calculated by the torque limit value calculation unit 76 is output as a command value from the torque limit value calculation unit 76 to the ISG controller 32, and the ISG controller 32, which is a generator control unit, The regenerative torque of the motor generator 16 is limited based on the torque limit value Tg. In this way, by limiting the regenerative torque of the motor generator 16 to the regenerative torque limit value Tg or less, the vehicle body deceleration during coasting can be suppressed to the ideal vehicle body deceleration Dx or less, which gives the passenger a sense of incongruity. The vehicle 11 can be driven without any problems.

  By the way, even when the regenerative torque is limited below the regenerative torque limit value Tg, if the regenerative torque limit value Tg fluctuates greatly, there is a possibility of giving a sense of incongruity to the occupant. Therefore, the control unit 60 has a torque change rate limit value calculation unit 86 for calculating the regenerative torque change rate limit value Rtg, and limits the update amount of the regenerative torque limit value Tg by the regenerative torque change rate limit value Rtg. ing.

  Hereinafter, a calculation procedure of the regenerative torque change rate limit value Rtg for limiting the renewal torque limit value Tg update amount will be described. As shown in FIG. 6, the control unit 60 includes an ideal deceleration change rate setting unit 80, an ideal work rate change rate calculation unit 81, a rolling resistance work rate change rate calculation unit 82, an air resistance work rate change rate calculation unit 83, The engine resistance power change rate calculation unit 84, the regenerative work rate change rate calculation unit 85, and the torque change rate limit value calculation unit 86 are provided.

  The ideal deceleration change rate setting unit 80 refers to a predetermined change rate map and sets an ideal vehicle body deceleration change rate Rdx that is an allowable change rate of vehicle body deceleration during coasting. Note that the ideal vehicle body deceleration change rate Rdx may be a fixed value, a value that changes according to the vehicle speed V, or a value that changes according to the deceleration. The ideal vehicle body deceleration change rate Rdx is a deceleration change rate that is allowed during coasting from the viewpoint of vehicle quality, and is an upper limit value of the deceleration change rate that does not give a sense of incongruity to the occupant. That is, during coasting, the vehicle 11 can be driven without greatly discomforting the occupant by suppressing the deceleration change rate of the vehicle 11 to be equal to or less than the ideal vehicle body deceleration change rate Rdx.

The ideal work rate change rate calculation unit (first change rate calculation unit) 81 is based on the following formula (11), from the ideal vehicle body deceleration change rate Rdx to the vehicle body ideal deceleration work rate change rate (first change rate) Rp1. Is calculated. The vehicle body ideal deceleration work rate change rate Rp1 is a work rate change rate necessary for changing the vehicle body deceleration by the ideal vehicle body deceleration change rate Rdx. That is, by changing the deceleration energy of the vehicle 11 along the vehicle body ideal deceleration power change rate Rp1, the vehicle body deceleration can be changed along the ideal vehicle body deceleration change rate Rdx. Note that “V _(n) ” shown in Expression (11) is the vehicle speed detected in the current control routine, and “V _(n−10) ” is the vehicle speed detected in the control routine 10 times before. , “T1” is a processing cycle, that is, a processing time per control routine.
Rp1 [W / s] = Wv [kg] × Rdx [m / s ³ ] × {V _(n) −V _(n−10) [m / s]} / {T1 [s] × 10} ( 11)

The rolling resistance work rate change rate calculation unit (second change rate calculation unit) 82 calculates the rolling resistance work rate change rate (second change rate) Rp2a from the vehicle speed V based on the following equation (12). This rolling resistance work rate change rate Rp2a is a change rate of the resistance work rate P2a based on the transition of the rolling resistance work rate P2a described above.
Rp2a [W / s] = μr × Wv [kg] × g [m / s ² ] × {V _(n) −V _(n−10) [m / s]} / {T1 [s] × 10}・ (12)

The air resistance power change rate calculation unit (second change rate calculation unit) 83 calculates the air resistance power change rate (second change rate) Rp2b from the vehicle speed V based on the following equation (13). The air resistance power change rate Rp2b is a change rate of the air resistance power P2b based on the transition of the air resistance power P2b described above.
Rp2b [W / s] = μl × ρ [kg / m ³ ] × S [m ² ] × {{V _(n) [m / s]} ³ − {V _(n−10) [m / s]} ³ } / {T1 [s] × 10} (13)

The engine resistance power change rate calculation unit (third change rate calculation unit) 84 calculates an engine friction work rate change rate (third change rate) Rp3 from the engine speed Ne based on the following equation (14). . The engine friction power change rate Rp3 is a change rate based on the transition of the engine friction power P3 described above. Note that “Tef _(n) ” shown in Expression (14) is the engine friction torque detected in the current control routine, and “Tef _(n−10) ” is the engine detected in the control routine 10 times before. Friction torque. In addition, “Ne _(n) ” shown in Expression (14) is the engine speed detected in this control routine, and “Ne _(n−10) ” is the engine detected in the control routine 10 times before. The number of revolutions.
Rp3 [W / s] = {Tef _(n) x Ne _(n) -Tef _(n-10) [Nm] x Ne _(n-10) [rad / s]} / {T1 [s] x 10}・ (14)

Based on the following equation (15), the regenerative work rate change rate calculation unit (upper limit work rate change rate calculation unit) 85 calculates the rolling resistance work rate change rate Rp2a, the air resistance work rate from the vehicle body ideal deceleration power rate change rate Rp1. By subtracting the rate change rate Rp2b and the engine friction work rate change rate Rp3, a deceleration regeneration power rate change rate (upper limit power rate change rate) Rpg is calculated. The deceleration regenerative work rate change rate Rpg is an upper limit value of a work rate change rate allowed for regenerative power generation during coasting, that is, a work rate change rate allowed for the motor generator 16 that performs regenerative power generation.
Rpg [W / s] = {Rp1-Rp2a-Rp2b-Rp3 [W / s]} (15)

The torque change rate limit value calculation unit (upper limit torque change rate calculation unit) 86 divides the deceleration regenerative work rate change rate Rpg by the rotational speed Nisg of the motor generator 16 based on the following equation (16) to limit the regenerative torque. A regenerative torque change rate limit value (upper limit torque change rate) Rtg, which is an upper limit change rate of the value Tg, is calculated. The regenerative torque change rate limit value Rtg is an upper limit value of the regenerative torque change rate allowed for the motor generator 16 during coasting.
Rtg [Nm / s] = Rpg [W / s] / Nisg [rad / s] (16)

Thus, the regenerative torque change rate limit value Rtg calculated by the torque change rate limit value calculation unit 86 is input to the torque limit value calculation unit 76 for calculating the regenerative torque limit value Tg. When the difference between the regenerative torque limit value Tg _(n) and the regenerative torque limit value Tg _(n-1) exceeds the regenerative torque change rate limit value Rtg, the torque limit value calculation unit 76 Based on Expression (17), the regenerative torque limit value Tg is updated. That is, the update amount of the regenerative torque limit value Tg is limited based on the regenerative torque change rate limit value Rtg. On the other hand, when the difference between the regenerative torque limit value Tg _(n) and the regenerative torque limit value Tg _(n-1) is equal to or less than the regenerative torque change rate limit value Rtg, based on the following equation (18), The regenerative torque limit value Tg _(n) calculated in the current control routine is updated as a new regenerative torque limit value Tg. “Tg _(n) ” shown in the equations (17) and (18) is the regenerative torque limit value calculated in the current control routine, and “Tg _(n−1) ” is calculated in the previous control routine. Is the regenerative torque limit value.
Tg _(n) [Nm] = Tg _(n-1) [Nm] + Rtg [Nm / s] × T1 [s] (17)
Tg _(n) [Nm] = Tg _(n) [Nm] (18)

  As described above, the regenerative torque limit value Tg calculated by the torque limit value calculation unit 76 is output as a command value from the torque limit value calculation unit 76 to the ISG controller 32, and the motor is based on the regenerative torque limit value Tg. The regenerative torque of the generator 16 is limited. In this way, by limiting the regenerative torque of the motor generator 16 to the regenerative torque limit value Tg or less, the vehicle body deceleration during coasting can be suppressed to the ideal vehicle body deceleration Dx or less, which gives the passenger a sense of incongruity. The vehicle 11 can be driven without any problems. Furthermore, since the update amount of the regenerative torque limit value Tg is limited based on the regenerative torque change rate limit value Rtg, an excessive change in the regenerative torque limit value Tg is suppressed. Thereby, since the rate of change of the vehicle body deceleration during coasting can be limited to the vehicle body ideal deceleration work rate change rate Rp1 or less, the vehicle can be made to travel without giving the passenger a sense of incongruity.

  That is, as shown in FIG. 7, when the depression of the accelerator pedal is released (symbol α), the motor generator 16 is controlled to the regenerative power generation state (symbol β), and the vehicle 11 enters a coasting state where the vehicle 11 is slowly decelerated. . At this time, as indicated by reference sign G1, the vehicle body deceleration (deceleration-side vehicle body acceleration) is suppressed so as not to exceed the ideal vehicle body deceleration Dx, so that the vehicle 11 can be driven without causing the passenger to feel uncomfortable. . Furthermore, since the vehicle body deceleration does not change beyond the ideal vehicle body deceleration change rate Rdx, the vehicle 11 can travel without giving a sense of incongruity to the occupant.

  Moreover, after converting into the power per unit time, that is, the energy per unit time, like the ideal body deceleration power P1, rolling resistance power P2a, air resistance power P2b, engine friction power P3 and deceleration regenerative power Pg, A regenerative torque limit value Tg for limiting the vehicle body deceleration to the ideal vehicle body deceleration Dx or less is calculated. Thus, by calculating the regenerative torque limit value Tg using the power, the regenerative torque limit value Tg can be calculated without constructing map data for every traveling situation. Thereby, the man-hour for constructing complicated map data can be reduced, and the cost of the vehicle control device 10 can be reduced. In addition, this control method calculates the regenerative torque limit value Tg from the ideal vehicle body deceleration Dx, and does not use complicated map data. Therefore, even when a disturbance occurs, the control stability (robustness) Property).

[Regenerative power generation control during coasting (flow chart)]
Next, the regenerative power generation control during coasting described above will be described with reference to a flowchart. FIG. 8 is a flowchart showing an example of an execution procedure of regenerative power generation control. As shown in FIG. 8, it is determined in step S10 whether or not the vehicle 11 is decelerating. When it is determined in step S10 that the vehicle 11 is decelerating, the process proceeds to step S11, and it is determined whether or not the fuel supply to the engine 12 is interrupted. If it is determined in step S11 that the fuel supply is cut off, that is, if it is determined that the vehicle 11 is in the coasting state, the process proceeds to step S12. In step S12, a regenerative torque limit value Tg which is an upper limit value of the regenerative torque of the motor generator 16 is calculated based on a predetermined ideal vehicle body deceleration Dx. Next, in step S13, a regenerative torque change rate limit value Rtg, which is an upper limit change rate of the regenerative torque limit value Tg, is calculated based on a predetermined ideal vehicle body deceleration change rate Rdx. In the subsequent step S14, the update amount of the regenerative torque limit value Tg is limited based on the regenerative torque change rate limit value Rtg. Subsequently, in step S15, it is determined whether or not the fuel supply to the engine 12 has been shut off, that is, whether or not the fuel supply to the engine 12 has been resumed. If it is determined in step S15 that the fuel supply is continuously cut off, the process proceeds to step S16, and the ISG controller 32 is instructed for the regenerative torque limit value Tg. The ISG controller 32 limits the regenerative torque of the motor generator 16 to the regenerative torque limit value Tg or less.

  On the other hand, if it is determined in step S11 or step S15 that fuel is being supplied to the engine 12, the process proceeds to step S17, and the target regeneration of the motor generator 16 is performed based on the target charging current of the lithium ion battery 41. Torque T1 is calculated. Next, in step S18, a regenerative torque change rate limit value Rtg that is a change rate upper limit value of the regenerative torque limit value Tg is calculated based on a predetermined ideal vehicle body deceleration change rate Rdx. In the subsequent step S19, the update amount of the target regenerative torque T1 is limited based on the regenerative torque change rate limit value Rtg. Then, the process proceeds to step S16, where the target regeneration torque T1 is instructed to the ISG controller 32. Then, the ISG controller 32 controls the regenerative torque of the motor generator 16 along the target regenerative torque T1.

[Other embodiments]
Next, another embodiment of the present invention will be described. In the above description, the excessive change of the regenerative torque limit value Tg is limited using the regenerative torque change rate limit value Rtg. However, the present invention is not limited to this. You may limit the change. Here, FIG. 9 is a block diagram showing an example of the control unit 91 constituting the vehicle control device 90 according to another embodiment of the present invention. That is, the vehicle control device 90 includes the control unit 91 shown in FIG. 9 instead of the control unit 60 described above. In FIG. 9, the same functional units as the functional units shown in FIG.

  As shown in FIG. 9, the control unit 91 includes a reference deceleration setting unit 92, a deceleration change rate calculating unit 93, an ideal deceleration calculating unit 94, an ideal power calculating unit 71, a rolling resistance power calculating unit 72, an air It has a resistance power calculation unit 73, an engine resistance power calculation unit 74, a regenerative power calculation unit 75, and a torque limit value calculation unit 76.

  The reference deceleration setting unit (reference deceleration update unit) 92 has a function of updating an ideal vehicle body deceleration reference value (reference deceleration) Dxb of a vehicle that is allowed during coasting for each predetermined processing cycle. Yes. The reference deceleration setting unit 92 refers to a predetermined deceleration map based on the vehicle speed V during coasting, and sets an ideal vehicle body deceleration reference value Dxb of the vehicle 11 for each predetermined processing cycle. For example, the ideal vehicle body deceleration reference value Dxb is set large at high vehicle speeds, while the ideal vehicle body deceleration reference value Dxb is set small at low vehicle speeds. This ideal vehicle body deceleration reference value Dxb is a deceleration allowed during coasting from the viewpoint of vehicle quality, and is an upper limit value of the deceleration that does not give a great sense of discomfort to the occupant. In other words, during coasting, the vehicle 11 can travel without giving a sense of discomfort to the occupant by suppressing the vehicle body deceleration to the ideal vehicle body deceleration reference value Dxb or less.

The deceleration change rate calculation unit (change rate update unit) 93 has a function of updating the vehicle body deceleration change rate (vehicle deceleration change rate) R1 during coasting every predetermined processing cycle. The deceleration change rate calculation unit 93 calculates the vehicle body deceleration change rate R1 for each predetermined processing cycle based on the following equation (20). That is, the deceleration change rate calculation unit 93 is allowed during coasting based on the difference between the updated ideal vehicle body deceleration reference value Dxb _(n) and the latest ideal vehicle body deceleration Dx _(n-1). The vehicle body deceleration change rate R1 is updated. Note that “Dxb _(n) ” shown in Expression (20) is the ideal vehicle deceleration reference value Dxb updated in the current control routine, and “Dx _(n−1) ” is calculated in the previous control routine. The most recent ideal vehicle body deceleration Dx, and “T1” is a processing cycle, that is, a processing time per control routine.
R1 [m / s ³ ] = {Dxb _(n) [m / s ² ] −Dx _(n−1) [m / s ² ]} / T1 [s] (20)

The ideal deceleration calculation unit (allowable deceleration update unit) 94 updates the ideal vehicle body deceleration (allowable deceleration) Dx for each predetermined processing cycle, and uses the updated ideal vehicle body deceleration Dx as the ideal power calculation unit ( (First work rate calculation unit) 71. The ideal deceleration calculation unit 94 calculates an ideal vehicle body deceleration Dx for each predetermined processing cycle based on the following formula (21) or (22). That is, the ideal deceleration calculation unit 94, the absolute value of the updated vehicle deceleration change rate R1 _(n) is equal to or less than the absolute value of the most recent vehicle deceleration change rate R1 _(n-1), the following The updated ideal vehicle body deceleration reference value Dxb _(n) is updated as the ideal vehicle body deceleration Dx using equation (21). On the other hand, when the absolute value of the updated vehicle body deceleration change rate R1 _(n) exceeds the absolute value of the latest vehicle body deceleration change rate R1 _(n-1) , the ideal deceleration calculation unit 94 Using equation (22), the ideal vehicle body deceleration Dx is updated based on the latest ideal vehicle body deceleration Dx _(n-1) . “R1 _(n) ” shown in the equation (22) is the vehicle body deceleration change rate R1 updated in the current control routine, and “R1 _(n−1) ” is calculated in the previous control routine. It is the latest vehicle body deceleration change rate R1. Further, “Dx _(n−1) ” shown in Expression (22) is the latest ideal vehicle body deceleration Dx calculated in the previous control routine, and “ΔR” is a predetermined deceleration change rate set in advance. It is.
When | R1 _(n) | ≦ | R1 _(n-1) |
Dx [m / s ² ] = Dxb _(n) [m / s ² ] (21)
| R1 _(n) | >> | R1 _(n-1) |
Dx [m / s ² ] = Dx _(n−1) [m / s ² ] + ΔR [m / s ³ ] × T1 [s] (22)

Here, FIGS. 10A to 10D are diagrams showing an example of the transition of the vehicle body deceleration change rate R1. FIGS. 10A and 10B show a situation in which the updated vehicle body deceleration change rate R1 _(n) is lower than the latest vehicle body deceleration change rate R1 _(n-1) . FIGS. 10C and 10D show a situation where the updated vehicle body deceleration change rate R1 _(n) exceeds the latest vehicle body deceleration change rate R1 _(n-1) . Further, FIGS. 11A and 11B are diagrams illustrating an example of a procedure for calculating the ideal vehicle body deceleration Dx.

  As shown in FIGS. 10 (a) and 10 (b), when the increase / decrease amount of the ideal vehicle deceleration Dx is reduced, the ideal vehicle deceleration Dx changes slowly, so that the passenger feels uncomfortable due to a sudden change in the deceleration. There is no fear of giving. Therefore, in a situation where the increase / decrease amount of the ideal vehicle body deceleration Dx is reduced, the ideal vehicle body deceleration reference value Dxb is set as a new ideal vehicle body deceleration Dx according to the above-described equation (21). On the other hand, as shown in FIGS. 10C and 10D, when the increase / decrease amount of the ideal vehicle deceleration Dx increases, even if the vehicle deceleration does not exceed the ideal vehicle deceleration Dx, the decrease is reduced. There is a risk that the passenger may feel uncomfortable due to a sudden change in speed. Therefore, in a situation where the increase / decrease amount of the ideal vehicle body deceleration Dx increases, the ideal vehicle body deceleration Dx is updated using the above-described equation (22), and the increase / decrease amount of the ideal vehicle body deceleration Dx is limited.

That is, as shown in FIG. 11A, the situation where the ideal vehicle deceleration Dx is updated using the above-described equation (22) is the ideal vehicle deceleration reference value set by the reference deceleration setting unit 92. The situation where Dxb is greatly increased from the latest ideal vehicle deceleration Dx _(n) , that is, the updated vehicle deceleration change rate R1 _(n) is the latest vehicle deceleration change rate R1 _(n-1) . It is the situation that exceeds. In this case, the latest ideal vehicle deceleration Dx _(n-1) is increased by a predetermined change amount ΔDx (ΔDx = ΔR × T1), and a new ideal vehicle deceleration Dx _(n) is calculated. That is, as shown by the arrow X1 in FIG. 11A, the updated value is updated even when the ideal vehicle body deceleration reference value Dxb is set far away from the most recent ideal vehicle body deceleration Dx _(n-1). The increase amount of the ideal vehicle body deceleration Dx _(n) can be suppressed. Thereby, the ideal vehicle body deceleration Dx can be changed gently.

As shown in FIG. 11B, the situation where the ideal vehicle deceleration Dx is updated using the above-described equation (22) is the ideal vehicle deceleration reference value set by the reference deceleration setting unit 92. The situation where Dxb is greatly reduced from the latest ideal vehicle body deceleration Dx _(n) , that is, the updated vehicle body deceleration change rate R1 _(n) becomes the latest vehicle body deceleration change rate R1 _(n-1) . It is the situation that exceeds. In this case, the latest ideal vehicle deceleration Dx _(n-1) is decreased by a predetermined change amount ΔDx (ΔDx = ΔR × T1), and a new ideal vehicle deceleration Dx _(n) is calculated. That is, as shown by an arrow X2 in FIG. 11B, the updated value is updated even when the ideal vehicle body deceleration reference value Dxb is set far away from the most recent ideal vehicle body deceleration Dx _(n-1). The reduction amount of the ideal vehicle body deceleration Dx _(n) can be suppressed. Thereby, the ideal vehicle body deceleration Dx can be changed gently.

  In this way, the ideal vehicle body deceleration Dx updated by the ideal deceleration calculation unit 94 is output from the ideal deceleration calculation unit 94 to the ideal power calculation unit 71. Similar to the control unit 60 described above, the ideal power reduction calculation unit 71 calculates the ideal vehicle deceleration deceleration P1, the regenerative power calculation unit 75 calculates the deceleration regenerative power Pg, and the torque limit value calculation unit 76. Thus, the regenerative torque limit value Tg is calculated. Thereafter, the regenerative torque limit value Tg is output from the torque limit value calculation unit 76 to the ISG controller 32, and the ISG controller 32 limits the regenerative torque of the motor generator 16 based on the regenerative torque limit value Tg. In this way, by limiting the regenerative torque of the motor generator 16 to the regenerative torque limit value Tg or less, the vehicle body deceleration during coasting can be suppressed to the ideal vehicle body deceleration Dx or less, which gives the passenger a sense of incongruity. The vehicle 11 can be driven without any problems.

  Here, FIG. 12 is a timing chart showing an example of the transition of the vehicle body deceleration during coasting. As shown in FIG. 12, when the depression of the accelerator pedal is released (symbol α), the motor generator 16 is controlled to a regenerative power generation state (symbol β), and the vehicle 11 enters a coasting state where the vehicle 11 is slowly decelerated. At this time, as indicated by reference sign G1, the vehicle body deceleration (deceleration-side vehicle body acceleration) is suppressed so as not to exceed the ideal vehicle body deceleration Dx, so that the vehicle 11 can be driven without causing the passenger to feel uncomfortable. . In addition, the ideal vehicle deceleration Dx is set not only based on the ideal vehicle deceleration reference value Dxb, but also set so that the vehicle deceleration change rate R1 does not increase or decrease excessively. The vehicle 11 can be run without causing the passenger to feel uncomfortable.

  It goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. In the illustrated example, the motor generator 16 that is an ISG is adopted as the generator, but the present invention is not limited to this, and an alternator may be adopted as the generator, and a motor generator that is a power source of the hybrid vehicle is used. It may be adopted as a generator. In the above description, the ISG controller 32 functions as a generator control unit. However, the present invention is not limited to this, and the control unit 60 may function as a generator control unit.

  In the above description, in order to calculate the deceleration regeneration power Pg, both the rolling resistance power P2a and the air resistance power P2b are used. However, the present invention is not limited to this. For example, the deceleration regeneration power Pg may be calculated without using the rolling resistance power P2a, and the deceleration regeneration power Pg may be calculated without using the air resistance power P2b. In the above description, both the rolling resistance power change rate Rp2a and the air resistance power change rate Rp2b are used to calculate the deceleration regenerative power change rate Rpg. However, the present invention is not limited to this. . For example, the deceleration regeneration power change rate Rpg may be calculated without using the rolling resistance power change rate Rp2a, or the deceleration regeneration power change rate Rpg may be calculated without using the air resistance power change rate Rp2b. good.

  In the above description, the engine friction power P3 is used to calculate the regenerative torque limit value Tg. However, the present invention is not limited to this, and the regenerative torque limit value Tg is not limited to the engine friction power P3. It may be calculated. In the above description, the engine friction work rate change rate Rp3 is used to calculate the regenerative torque change rate limit value Rtg. However, the present invention is not limited to this, and the engine friction work rate change rate Rp3 is used. Alternatively, the regenerative torque change rate limit value Rtg may be calculated. In the above description, the regenerative torque change rate limit value Rtg is calculated based on the vehicle speed V, the engine speed Ne, and the like. However, the present invention is not limited to this. For example, a fixed value may be set as the regenerative torque change rate limit value Rtg.

  Note that the power supply circuit included in the vehicle control device 10 is not limited to the illustrated power supply circuit 40. For example, the power supply circuit 40 shown in the figure is provided with a lithium ion battery 41 and a lead battery 42. However, the power supply circuit 40 is not limited to this and may be a power supply circuit including one power storage unit. In the illustrated example, the switch SW1 is provided in the negative electrode line 47 of the lithium ion battery 41, but the present invention is not limited to this. For example, a switch SW <b> 1 may be provided in the positive electrode line 43 of the lithium ion battery 41 as indicated by a dashed line in FIG. 2.

DESCRIPTION OF SYMBOLS 10 Vehicle control apparatus 11 Vehicle 12 Engine 16 Motor generator (generator)
32 ISG controller (power generation control unit)
60 control unit 71 ideal power calculation unit (first power calculation unit)
72 Rolling resistance power calculation unit (second power calculation unit)
73 Air resistance power calculation unit (second power calculation unit)
74 Engine resistance power calculation unit (third power calculation unit)
75 regenerative work rate calculation part (upper limit work rate calculation part)
76 Torque limit value calculation unit (upper limit torque calculation unit)
81 Ideal work rate change rate calculation unit (first change rate calculation unit)
82 Rolling resistance work rate change rate calculation unit (second change rate calculation unit)
83 Air resistance power change rate calculation unit (second change rate calculation unit)
84 Engine resistance power change rate calculation unit (third change rate calculation unit)
85 regenerative work rate change rate calculation part (upper limit work rate change rate calculation part)
86 Torque change rate limit value calculation unit (upper limit torque change rate calculation unit)
90 vehicle control device 91 control unit 92 reference deceleration setting unit (reference deceleration update unit)
93 Deceleration rate change rate calculation unit (change rate update unit)
94 Ideal deceleration calculation unit (allowable deceleration update unit)
Dx Ideal vehicle deceleration (allowable deceleration)
P1 Body ideal deceleration power (first deceleration power)
P2a Rolling resistance power (second deceleration power)
P2b Air resistance power (second deceleration power)
P3 Engine friction power (third deceleration power)
Pg Deceleration regenerative work rate (upper limit work rate)
Tg Regenerative torque limit value (upper limit torque)
Rdx Ideal body deceleration change rate (allowable change rate)
Rp1 Body ideal deceleration power change rate (1st change rate)
Rp2a Rolling resistance power change rate (2nd change rate)
Rp2b Air resistance work rate change rate (second change rate)
Rp3 Engine friction work rate change rate (3rd change rate)
Rpg Decrease regenerative work rate change rate (upper limit work rate change rate)
Rtg Regenerative torque change rate limit value (upper limit torque change rate)
Dxb Ideal vehicle deceleration reference value (reference deceleration)
R1 Body deceleration change rate (change rate)
V Vehicle speed (traveling speed)
Ne engine speed (speed)

Claims (6)

A vehicle control device for controlling a generator connected to an engine,
A first power calculation unit that calculates a first deceleration power for causing the vehicle deceleration to reach the allowable deceleration based on the allowable deceleration of the vehicle during coasting;
A second power calculation unit that calculates a second deceleration work rate corresponding to a travel resistance for decelerating the vehicle based on the travel speed of the vehicle during coasting;
An upper limit power calculation unit for subtracting the second reduction power from the first reduction power and calculating an upper limit power of the generator;
An upper limit torque calculation unit for calculating an upper limit torque of the generator based on the upper limit power of the generator;
Based on the upper limit torque, a generator control unit that limits the power generation torque of the generator during coasting,
A vehicle control device. The vehicle control device according to claim 1,
A third power calculation unit that calculates a third reduction power for an engine rotation resistance that decelerates the vehicle based on the rotation speed of the engine;
The upper limit power calculation unit is a vehicle control device that calculates the upper limit power of the generator by subtracting the second deceleration power and the third deceleration power from the first deceleration power. The vehicle control device according to claim 1 or 2,
A first rate-of-change calculating unit that calculates a first rate of change of the deceleration power for changing the vehicle deceleration at the allowable rate of change based on an allowable rate of change of the vehicle deceleration during coasting;
A second rate-of-change calculator that calculates a second rate of change of the second mode of deceleration based on the transition of the second mode of deceleration;
An upper limit work rate change rate calculating unit that subtracts the second change rate from the first change rate and calculates an upper limit work rate change rate that is an upper limit change rate of the upper limit work rate;
An upper limit torque change rate calculating unit that calculates an upper limit torque change rate that is an upper limit change rate of the upper limit torque based on the upper limit work rate change rate;
The upper limit torque calculation unit is a vehicle control device that limits an update amount of the upper limit torque based on the upper limit torque change rate. The vehicle control device according to claim 2,
A first rate-of-change calculating unit that calculates a first rate of change of the deceleration power for changing the vehicle deceleration at the allowable rate of change based on an allowable rate of change of the vehicle deceleration during coasting;
A second rate-of-change calculator that calculates a second rate of change of the second mode of deceleration based on the transition of the second mode of deceleration;
A third rate-of-change calculator that calculates a third rate of change of the third mode of deceleration based on the transition of the third mode of deceleration;
An upper limit work rate change rate calculating unit that subtracts the second change rate and the third change rate from the first change rate to calculate an upper limit work rate change rate that is an upper limit change rate of the upper limit work rate;
An upper limit torque change rate calculating unit that calculates an upper limit torque change rate that is an upper limit change rate of the upper limit torque based on the upper limit work rate change rate;
The upper limit torque calculation unit is a vehicle control device that limits an update amount of the upper limit torque based on the upper limit torque change rate. The vehicle control device according to claim 1 or 2,
An allowable deceleration update unit that updates the allowable deceleration and outputs the updated value to the first power calculation unit;
A reference deceleration update unit that updates a reference deceleration of the vehicle that is allowed during coasting based on the traveling speed of the vehicle during coasting;
A rate-of-change updater that updates the rate of change of vehicle deceleration during coasting based on the difference between the updated reference deceleration and the latest allowable deceleration,
The allowable deceleration update unit updates the allowable deceleration based on the latest allowable deceleration when the updated change rate exceeds the latest change rate, and updates the updated allowable deceleration. A vehicle control device that outputs to the first power calculation unit. The vehicle control device according to claim 5, wherein
The allowable deceleration update unit outputs the updated reference deceleration as the allowable deceleration to the first power calculation unit when the updated change rate is lower than the latest change rate. Control device.

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