JP4770756B2 - Vehicle and control method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress deterioration of a battery for performing exchange of power between a first motor and a second motor if a slip occurs when execution of control for suppressing the slip is indicated in a vehicle in which a sun gear, a carrier, and a ring gear of a planetary gear are respectively connected to the first motor, an engine, and the second motor. <P>SOLUTION: When traction control is directed to be off, and if an absolute value of input limit Win of the battery during the occurance of slip is smaller than a threshold value Wth (step S150, S160), the slip is suppresses by limiting torque to be output from the second motor so as to be smaller as rotation angle acceleration &alpha; of the second motor becomes larger (step S180 to S200). Thereby rapid increase of rotation number of the first motor caused by resolving the slip can be suppressed, and the battery can be prevented from being charged by excessive power. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a vehicle and a control method thereof.

Conventionally, this type of vehicle is connected to an engine, a planetary gear mechanism in which a carrier is connected to a crankshaft of the engine and a ring gear to a drive shaft connected to a drive wheel, and a sun gear of the planetary gear mechanism. A device including a generator, an electric motor connected to a drive shaft, and a battery that exchanges electric power with the generator and the electric motor has been proposed (for example, see Patent Document 1). In this vehicle, when the drive wheel is slipping, slip suppression control is performed to control the engine, generator, and motor so that power that suppresses slip is output to the drive shaft within the range of power that can be input to the battery. By doing so, the slip of the drive wheel is suppressed.
JP 2005-51887 A

  By the way, in such a vehicle, in order to cope with the case where the driver wants to idle the driving wheel intentionally, such as when trying to escape from the stacked state or when the driver requests agile acceleration by idling the driving wheel, Some include a switch that instructs to turn off the slip suppression control described above. If slip occurs when an instruction to turn off the slip suppression control is given by such a switch, the battery may be charged with excessive electric power due to the power generation of the generator depending on the operating state of the engine or the generator. When the battery is charged with such excessive power, deterioration of the battery may be promoted when the maximum allowable power for charging the battery is relatively small, such as when the battery is cold.

  An object of the vehicle and the control method of the present invention is to suppress deterioration of the power storage device.

  The vehicle and the control method thereof according to the present invention employ the following means in order to achieve the above-described object.

The vehicle of the present invention
An internal combustion engine;
Power is applied to the remaining shafts based on power input / output to / from any two of the three shafts connected to three shafts of the output shaft of the internal combustion engine, a drive shaft connected to the drive wheels, and a third shaft. 3-axis power input / output means for input / output;
A generator capable of inputting and outputting power to the third shaft;
An electric motor capable of outputting power to the drive shaft;
Power storage means capable of exchanging electric power with the generator and the motor;
A slip suppression instruction switch for instructing whether or not to execute slip suppression control for suppressing slip due to idling of the drive wheel;
Slip detecting means for detecting slip due to idling of the drive wheel;
Input limit setting means for setting an input limit as the maximum allowable power when charging the power storage means based on the state of the power storage means;
Requested driving force setting means for setting a requested driving force required for the drive shaft based on an operation of the driver;
When slip is detected by the slip detection means when execution of the slip suppression control is not instructed by the slip suppression instruction switch, the slip suppression control is executed when the set input limit is a predetermined power or more. Without controlling the internal combustion engine, the generator and the motor so that a driving force based on the set required driving force is output to the driving shaft, and the set input limit is less than the predetermined power. In some cases, the slip suppression control is executed regardless of an instruction from the slip suppression instruction switch, and the driving force based on the set required driving force is output to the drive shaft. Control means for controlling the electric motor;
It is a summary to provide.

  In the vehicle according to the present invention, the input restriction is set as the maximum allowable power when charging the power storage means based on the state of the power storage means, and the required driving force required for the drive shaft is set based on the operation of the driver When slip detection is detected by the slip detection means when the slip suppression instruction switch does not instruct execution of the slip suppression control, the slip suppression control is not executed when the set input limit is equal to or greater than the predetermined power. The internal combustion engine, the generator, and the motor are controlled so that a driving force based on the set required driving force is output to the drive shaft. Thereby, it can drive | work according to a driver | operator's intention. On the other hand, when the set input limit is less than the predetermined power, the slip suppression control is executed regardless of the instruction by the slip suppression instruction switch, and the driving force based on the set required driving force is output to the drive shaft. The engine, generator and motor are controlled. When slipping occurs due to idling of the drive wheels, the rotational speed of the generator rapidly increases when the slip is eliminated, and the power storage means may be charged with large electric power depending on the driving state of the generator or the motor. At this time, if the set input limit is relatively small, the charging of the power storage unit by such a large amount of power may promote the deterioration of the power storage unit. However, when the set input limit is less than the predetermined power, slipping occurs. By executing the suppression control, a rapid increase in the number of revolutions of the generator is suppressed, so that deterioration of the power storage means that occurs when the power storage means is charged with large electric power can be suppressed. Here, the “predetermined electric power” may be set based on the degree of slip, and the power storage means may be set after the slip occurs until the vehicle returns to a steady driving state after the slip is eliminated. Includes the maximum average power to charge.

  In such a vehicle of the present invention, the control means may be means for executing control for limiting power output from the electric motor to the drive shaft as the slip suppression control. Braking force applying means capable of applying braking force is provided, and the control means is means for executing control for applying braking force to the drive wheel by the braking force applying means as the slip suppression control. You can also. If it carries out like this, a slip can be suppressed using an electric motor and braking force provision means.

The vehicle control method of the present invention includes:
An internal combustion engine, an output shaft of the internal combustion engine, a drive shaft connected to a drive wheel, and a third shaft, which are connected to three shafts and the remaining power based on power input / output to / from any two of the three shafts 3-axis power input / output means for inputting / outputting power to / from the shaft, a generator capable of inputting / outputting power to / from the third shaft, an electric motor capable of outputting power to the drive shaft, the generator and the electric motor And a power storage means capable of exchanging electric power, and a slip suppression instruction switch for instructing whether or not to execute slip suppression control for suppressing slip due to idling of the drive wheels,
Input limit setting means for setting an input limit as the maximum allowable power when charging the power storage means based on the state of the power storage means;
Requested driving force setting means for setting a requested driving force required for the drive shaft based on an operation of the driver;
When slippage due to idling of the drive wheel occurs when the slip suppression instruction switch does not instruct execution of the slip suppression control, the slip suppression control is executed when the set input limit is equal to or greater than a predetermined power. Without controlling the internal combustion engine, the generator and the motor so that a driving force based on the set required driving force is output to the driving shaft, and the set input limit is less than the predetermined power. In some cases, the slip suppression control is executed regardless of an instruction from the slip suppression instruction switch, and the driving force based on the set required driving force is output to the drive shaft. The gist is to control the motor.

  In the vehicle according to the present invention, the input restriction is set as the maximum allowable power when charging the power storage means based on the state of the power storage means, and the required driving force required for the drive shaft is set based on the operation of the driver When slippage due to idling of the drive wheels occurs when the slip suppression instruction switch is not instructed to execute slip suppression control, slip suppression control is not performed when the set input limit is greater than or equal to a predetermined power. The internal combustion engine, the generator, and the motor are controlled so that a driving force based on the set required driving force is output to the drive shaft. Thereby, it can drive | work according to a driver | operator's intention. On the other hand, when the set input limit is less than the predetermined power, the slip suppression control is executed regardless of the instruction by the slip suppression instruction switch, and the driving force based on the set required driving force is output to the drive shaft. The engine, generator and motor are controlled. When slipping occurs due to idling of the drive wheels, the rotational speed of the generator rapidly increases when the slip is eliminated, and the power storage means may be charged with large electric power depending on the driving state of the generator or the motor. At this time, if the set input limit is relatively small, the charging of the power storage unit by such a large amount of power may promote the deterioration of the power storage unit. However, when the set input limit is less than the predetermined power, slipping occurs. By executing the suppression control, a rapid increase in the number of revolutions of the generator is suppressed, so that deterioration of the power storage means that occurs when the power storage means is charged with large electric power can be suppressed. Here, the “predetermined electric power” may be set based on the degree of slip, and the power storage means may be set after the slip occurs until the vehicle returns to a steady driving state after the slip is eliminated. Includes the maximum average power to charge.

  Next, the best mode for carrying out the present invention will be described using examples.

  FIG. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 as an embodiment of the present invention. As shown in the figure, the hybrid vehicle 20 of the embodiment includes an engine 22, a three-shaft power distribution / integration mechanism 30 connected to a crankshaft 26 as an output shaft of the engine 22 via a damper 28, and power distribution / integration. A motor MG1 capable of generating electricity connected to the mechanism 30, a reduction gear 35 attached to a ring gear shaft 32a as a drive shaft connected to the power distribution and integration mechanism 30, a motor MG2 connected to the reduction gear 35, A brake actuator 92 for controlling the brakes of the drive wheels 39a and 39b and driven wheels (not shown) and a hybrid electronic control unit 70 for controlling the entire vehicle are provided.

  The engine 22 is an internal combustion engine that outputs power using a hydrocarbon-based fuel such as gasoline or light oil, and an engine electronic control unit (hereinafter referred to as an engine ECU) that receives signals from various sensors that detect the operating state of the engine 22. ) 24 is subjected to operation control such as fuel injection control, ignition control, intake air amount adjustment control and the like. The engine ECU 24 is in communication with the hybrid electronic control unit 70, controls the operation of the engine 22 by a control signal from the hybrid electronic control unit 70, and, if necessary, transmits data related to the operating state of the engine 22 to the hybrid electronic control. Output to unit 70. The engine ECU 24 also calculates the rotational speed of the crankshaft 26, that is, the rotational speed Ne of the engine 22 based on a signal from a crank position sensor (not shown) attached to the crankshaft 26.

  The power distribution and integration mechanism 30 includes an external gear sun gear 31, an internal gear ring gear 32 arranged concentrically with the sun gear 31, a plurality of pinion gears 33 that mesh with the sun gear 31 and mesh with the ring gear 32, A planetary gear mechanism is provided that includes a carrier 34 that holds a plurality of pinion gears 33 so as to rotate and revolve, and that performs differential action using the sun gear 31, the ring gear 32, and the carrier 34 as rotational elements. In the power distribution and integration mechanism 30, the crankshaft 26 of the engine 22 is connected to the carrier 34, the motor MG1 is connected to the sun gear 31, and the reduction gear 35 is connected to the ring gear 32 via the ring gear shaft 32a. When functioning as a generator, power from the engine 22 input from the carrier 34 is distributed according to the gear ratio between the sun gear 31 side and the ring gear 32 side, and when the motor MG1 functions as an electric motor, the engine input from the carrier 34 The power from 22 and the power from the motor MG1 input from the sun gear 31 are integrated and output to the ring gear 32 side. The power output to the ring gear 32 is finally output from the ring gear shaft 32a to the drive wheels 39a and 39b of the vehicle through the gear mechanism 37 and the differential gear 38.

  The motor MG1 and the motor MG2 are both configured as well-known synchronous generator motors that can be driven as generators and can be driven as motors, and exchange power with the battery 50 via inverters 41 and 42. The power line 54 connecting the inverters 41 and 42 and the battery 50 is configured as a positive electrode bus and a negative electrode bus shared by the inverters 41 and 42, and the electric power generated by one of the motors MG1 and MG2 It can be consumed by a motor. Therefore, battery 50 is charged / discharged by electric power generated from one of motors MG1 and MG2 or insufficient electric power. If the balance of electric power is balanced by the motors MG1 and MG2, the battery 50 is not charged / discharged. The motors MG1 and MG2 are both driven and controlled by a motor electronic control unit (hereinafter referred to as a motor ECU) 40. The motor ECU 40 detects signals necessary for driving and controlling the motors MG1 and MG2, such as signals from rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2, and current sensors (not shown). The phase current applied to the motors MG1 and MG2 to be applied is input, and a switching control signal to the inverters 41 and 42 is output from the motor ECU 40. The motor ECU 40 is in communication with the hybrid electronic control unit 70, controls the driving of the motors MG1 and MG2 by a control signal from the hybrid electronic control unit 70, and, if necessary, data on the operating state of the motors MG1 and MG2. Output to the hybrid electronic control unit 70. The motor ECU 40 also calculates the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 based on signals from the rotational position detection sensors 43 and 44.

The battery 50 is managed by a battery electronic control unit (hereinafter referred to as a battery ECU) 52. The battery ECU 52 receives signals necessary for managing the battery 50, for example, a voltage between terminals from a voltage sensor (not shown) installed between terminals of the battery 50, and a power line 54 connected to the output terminal of the battery 50. The charging / discharging current from the attached current sensor (not shown), the battery temperature Tb from the temperature sensor 51 attached to the battery 50, and the like are input. Output to the control unit 70. The battery ECU 52 calculates the remaining capacity (SOC) based on the integrated value of the charge / discharge current detected by the current sensor in order to manage the battery 50, or calculates the remaining capacity (SOC) and the battery temperature Tb. Based on the above, the input / output limits Win and Wout of the battery 50 are calculated. The input / output limits Win and Wout of the battery 50 are set to basic values of the input / output limits Win and Wout based on the battery temperature Tb, and the output limiting correction coefficient and the input limiting limit are set based on the remaining capacity (SOC) of the battery 50. It can be set by setting a correction coefficient and multiplying the basic value of the set input / output limits Win and Wout by the correction coefficient. FIG. 2 shows an example of the relationship between the battery temperature Tb and the input / output limits Win, Wout, and FIG. 3 shows an example of the relationship between the remaining capacity (SOC) of the battery 50 and the correction coefficients of the input / output limits Win, Wout.

  The brake actuator 92 has a braking torque corresponding to the share of the brake in the braking force applied to the vehicle by the pressure (brake pressure) of the brake master cylinder 90 and the vehicle speed V generated in response to the depression of the brake pedal 85. The brake wheel cylinders 96a and 96d are adjusted so as to act on the wheel 39b and a driven wheel (not shown), and the braking torque acts on the drive wheels 39a and 39b and the driven wheel regardless of the depression of the brake pedal 85. The hydraulic pressures of 96a to 96d can be adjusted. Hereinafter, a case where a braking force is applied to the drive wheels 39a and 39b and a driven wheel (not shown) by the operation of the brake actuator 92 is referred to as a hydraulic brake. The brake actuator 92 is controlled by a brake electronic control unit (hereinafter referred to as a brake ECU) 94. The brake ECU 94 inputs signals such as a wheel speed from a wheel speed sensor (not shown) attached to the drive wheels 39a and 39b and the driven wheel and a steering angle from a steering angle sensor (not shown) through a signal line (not shown). Anti-lock brake system function (ABS) that suppresses any of the driving wheels 39a, 39b and the driven wheels from slipping due to locking when the driver depresses the brake pedal 85, or when the driver depresses the accelerator pedal 83 A traction control (TRC) that suppresses slipping of any of the drive wheels 39a and 39b due to idling, a posture holding control (VSC) that holds the posture while the vehicle is turning, and the like are also performed. The brake ECU 94 communicates with the hybrid electronic control unit 70, and controls the drive of the brake actuator 92 by a control signal from the hybrid electronic control unit 70, and the data regarding the state of the brake actuator 92 is used for the hybrid as necessary. Output to the electronic control unit 70.

  The hybrid electronic control unit 70 is configured as a microprocessor centered on the CPU 72, and in addition to the CPU 72, a ROM 74 for storing processing programs, a RAM 76 for temporarily storing data, an input / output port and communication not shown. And a port. The hybrid electronic control unit 70 includes an ignition signal from an ignition switch 80, a shift position SP from a shift position sensor 82 that detects the operation position of the shift lever 81, and an accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. The accelerator pedal opening Acc from the vehicle, the brake pedal position BP from the brake pedal position sensor 86 for detecting the depression amount of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 88, and the wheel speed attached to the rotation shafts of the drive wheels 39a and 39b. The wheel speeds Vl and Vr from the sensors 89b and 89c, the TRC off signal from the TRC off switch 89a for turning off the traction control provided near the driver's seat, and the like are input via the input port. As described above, the hybrid electronic control unit 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port, and the engine ECU 24, the motor ECU 40, the battery ECU 52, the brake ECU 94, and various control signals and data. We are exchanging.

The hybrid vehicle 20 of the embodiment thus configured calculates the required torque to be output to the ring gear shaft 32a as the drive shaft based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal 83 by the driver. Then, the operation of the engine 22, the motor MG1, and the motor MG2 is controlled so that the required power corresponding to the required torque is output to the ring gear shaft 32a. As operation control of the engine 22, the motor MG1, and the motor MG2, the operation of the engine 22 is controlled so that power corresponding to the required power is output from the engine 22, and all of the power output from the engine 22 is the power distribution and integration mechanism 30. And motor MG1
And the motor MG2 convert the torque to be output to the ring gear shaft 32a. The torque conversion operation mode for driving and controlling the motor MG1 and the motor MG2 and the power suitable for the sum of the required power and the power required for charging and discharging the battery 50 are obtained. The operation of the engine 22 is controlled so as to be output from the engine 22, and all or a part of the power output from the engine 22 with charging / discharging of the battery 50 is performed by the power distribution and integration mechanism 30, the motor MG1, and the motor MG2. Charge / discharge operation mode in which the motor MG1 and the motor MG2 are driven and controlled so that the required power is output to the ring gear shaft 32a with torque conversion, and the power corresponding to the required power from the motor MG2 by stopping the operation of the engine 22 There is a motor operation mode in which operation control is performed to output to 32a.

  Next, the operation of the hybrid vehicle 20 of the embodiment configured as described above, particularly the operation when the driver gives an instruction to turn off the traction control will be described. Here, when the driver gives an instruction to turn off the traction control, for example, when the vehicle that is stuck is escaped or when the driver idles the driving wheel to request agile acceleration There is. FIG. 4 is a flowchart showing an example of a drive control routine executed by the hybrid electronic control unit 70. This routine is repeatedly executed every predetermined time (for example, every several milliseconds) when the TRC off signal is input from the TRC off switch 89a.

  When the drive control routine is executed, the CPU 72 of the hybrid electronic control unit 70 firstly sets the accelerator opening Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 88, and the wheels from the wheel speed sensors 89b and 89c. A process of inputting data necessary for control such as the speeds Vl, Vr, the rotational speeds Nm1, Nm2 of the motors MG1, MG2, the rotational angular acceleration α of the motor MG2, the input / output limits Win, Wout of the battery 50 is executed (step S100). . Here, the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 are input from the motor ECU 40 by communication from those calculated based on the rotational positions of the rotors of the motors MG1 and MG2 detected by the rotational position detection sensors 43 and 44. To do. The rotational angular acceleration α of the motor MG2 is calculated from the rotational position of the rotor of the motors MG1 and MG2 detected by the rotational position detection sensors 43 and 44, and is input from the motor ECU 40 by communication. . Further, the input / output limits Win and Wout of the battery 50 are set based on the battery temperature Tb of the battery 50 and the remaining capacity (SOC) of the battery 50 and input from the battery ECU 52 by communication.

  When the data is input in this way, the required torque Tr * to be output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 39a, 39b as the torque required for the vehicle based on the input accelerator opening Acc and the vehicle speed V. And the required power Pe * required for the engine 22 is set (step S110). In the embodiment, the required torque Tr * is determined in advance by storing the relationship between the accelerator opening Acc, the vehicle speed V, and the required torque Tr * in the ROM 74 as a required torque setting map, and the accelerator opening Acc, the vehicle speed V, , The corresponding required torque Tr * is derived and set from the stored map. FIG. 5 shows an example of the required torque setting map. The required power Pe * can be calculated as the sum of the set required torque Tr * multiplied by the rotational speed Nr of the ring gear shaft 32a and the charge / discharge required power Pb * required by the battery 50 and the loss Loss. The rotational speed Nr of the ring gear shaft 32a is obtained by multiplying the vehicle speed V by a conversion factor k (Nr = k · V), or the rotational speed Nm2 of the motor MG2 is divided by the gear ratio Gr of the reduction gear 35 (Nr = Nm2 / Gr).

  Subsequently, a target rotational speed Ne * and a target torque Te * are set as operating points at which the engine 22 should be operated based on the set required power Pe * (step S120). This setting is performed based on the operation line for efficiently operating the engine 22 and the required power Pe *. FIG. 6 shows an example of the operation line of the engine 22 and how the target rotational speed Ne * and the target torque Te * are set. As shown in the figure, the target rotational speed Ne * and the target torque Te * can be obtained from the intersection of the operation line and a curve with a constant required power Pe * (Ne * × Te *).

  Next, using the set target rotational speed Ne *, the rotational speed Nr (Nm2 / Gr) of the ring gear shaft 32a, and the gear ratio ρ of the power distribution and integration mechanism 30, the target rotational speed Nm1 of the motor MG1 is given by the following equation (1). * And a torque command Tm1 * of the motor MG1 is calculated by the equation (2) based on the calculated target rotational speed Nm1 * and the current rotational speed Nm1 (step S 1). Here, Expression (1) is a dynamic relational expression for the rotating element of the power distribution and integration mechanism 30. FIG. C shows a collinear diagram showing a dynamic relationship between the number of rotations and torque in the rotating elements of the power distribution and integration mechanism 30. In the figure, the left S-axis indicates the rotation speed of the sun gear 31 that is the rotation speed Nm1 of the motor MG1, the C-axis indicates the rotation speed of the carrier 34 that is the rotation speed Ne of the engine 22, and the R-axis indicates the rotation speed of the motor MG2. The rotational speed Nr of the ring gear 32 obtained by dividing the number Nm2 by the gear ratio Gr of the reduction gear 35 is shown. Expression (1) can be easily derived by using this alignment chart. The two thick arrows on the R axis indicate that the torque Tm1 output from the motor MG1 acts on the ring gear shaft 32a and the torque Tm2 output from the motor MG2 acts on the ring gear shaft 32a via the reduction gear 35. Torque. Expression (2) is a relational expression in feedback control for rotating the motor MG1 at the target rotational speed Nm1 *. In Expression (2), “k1” in the second term on the right side is a gain of a proportional term. “K2” in the third term on the right side is the gain of the integral term.

Nm1 * = Ne * ・ (1 + ρ) / ρ-Nm2 / (Gr ・ ρ) (1)
Tm1 * = previous Tm1 * + k1 (Nm1 * -Nm1) + k2∫ (Nm1 * -Nm1) dt (2)

  When the torque command Tm1 * is set in this way, the torque command Tm1 * set to the required torque Tr * is divided by the gear ratio ρ of the power distribution and integration mechanism 30 and further divided by the gear ratio Gr of the reduction gear 35 to obtain the motor. A temporary torque Tm2tmp, which is a temporary value of the torque to be output from MG2, is calculated by the following equation (3) (step S140), and it is determined whether or not the vehicle is slipping (step S150). . This determination can be made by comparing the vehicle speed based on the wheel speeds Vl and Vr and the vehicle speed V from the vehicle speed sensor 88, and determining that the vehicle is slipping by a value obtained by subtracting the vehicle speed V from the vehicle speed based on the wheel speeds Vl and Vr. It is determined that slipping due to idling of the drive wheels 39a and 39b is occurring when the value is equal to or greater than a predetermined threshold value as a lower limit value. When slipping due to idling of the drive wheels 39a, 39b has not occurred, the motor obtained by multiplying the torque command Tm1 * set by the input / output limits Win, Wout of the battery 50 and the current rotational speed Nm1 of the motor MG1. Torque limits Tm2min and Tm2max as upper and lower limits of the torque that may be output from the motor MG2 by dividing the deviation from the power consumption (generated power) of MG1 by the rotation speed Nm2 of the motor MG2 are expressed by the following equations (4) and ( 5) (step S170), and the set temporary torque Tm2tmp is limited by the torque limits Tm2min and Tm2max using equation (6) to set the torque command Tm2 * of the motor MG2 (step S190). Here, Expression (3) can be easily derived from the alignment chart of FIG.

Tm2tmp = (Tr * + Tm1 * / ρ) / Gr (3)
Tm2min = (Win-Tm1 * ・ Nm1) / Nm2 (4)
Tm2max = (Wout-Tm1 * ・ Nm1) / Nm2 (5)
Tm2 * = max (min (Tm2tmp, Tm2max), Tm2min) (6)

  Thus, when the target engine speed Ne *, the target torque Te *, and the torque commands Tm1 *, Tm2 * of the motors MG1, MG2 are set, the target engine speed Ne * and the target torque Te * of the engine 22 are set in the engine ECU 24. Torque commands Tm1 * and Tm2 * for motors MG1 and MG2 are transmitted to motor ECU 40 (step S200), and the drive control routine is terminated. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * controls the intake air amount in the engine 22 so that the engine 22 is operated at the operating point indicated by the target rotational speed Ne * and the target torque Te *. Controls such as fuel injection control and ignition control. The motor ECU 40 that has received the torque commands Tm1 * and Tm2 * controls the switching elements of the inverters 41 and 42 so that the motor MG1 is driven by the torque command Tm1 * and the motor MG2 is driven by the torque command Tm2 *. To do. Thus, when slipping due to idling of the drive wheels 39a and 39b does not occur, the engine 22 is efficiently operated within the range of the input / output limits Win and Wout of the battery 50, and the required torque Tr * is output to the ring gear shaft 32a as the drive shaft. And can travel.

  On the other hand, when slipping due to idling of the drive wheels 39a and 39b occurs (step S150), the absolute value of the input limit Win, that is, the maximum allowable power for charging the battery 50 and the threshold value Wth are subsequently compared. (Step S160). Here, the threshold value Wth is the maximum value of the average power that charges the battery 50 until the vehicle returns to a steady driving state after the slip is eliminated when the control for suppressing the slip is not executed. Is previously determined by experiment and is set to a value slightly higher than the maximum value. The reason for making such a determination in the process of step S160 is based on the following reason. FIG. 9 is a collinear diagram showing an example of the relationship between the rotational speeds of the rotating elements of the power distribution and integration mechanism 30 when slipping occurs due to idling of the drive wheels 39a and 39b. In the figure, the solid line shows an example of the relationship between the rotational speeds of each rotating element before slipping, the broken line shows an example of the relationship between the rotational speeds of each rotating element when slipping occurs, and the alternate long and short dash line indicates a slip 3 shows an example of the relationship between the rotational speeds of the respective rotating elements when is resolved. Considering the case where the instruction to turn off the traction control is given by the TRC off switch 89a, the case where the control for suppressing the slip is not performed is considered here. When slipping due to idling occurs in the drive wheels 39a and 39b as shown by broken lines in the figure and then the slip is eliminated as shown by the alternate long and short dash line in the figure, the motor is accompanied by a sudden decrease in the rotational speed of the ring gear shaft 32a as the drive shaft 36. Although the rotational speed Nm1 of MG1 increases rapidly, if a torque is output in a direction to decrease the rotational speed Nm1 of the motor MG1 (downward in the figure) in order to prevent the motor MG1 from over-rotating, the battery is generated by the power generation of the motor MG1. 50 may be charged with large power. At this time, when the absolute value of the input limit Win, that is, the maximum allowable power when charging the battery 50 is relatively large, the power generated by the motor MG1 does not exceed the input limit Win, but the input is performed when the battery temperature is low. This is because when the absolute value of the limit Win, that is, the maximum allowable power for charging the battery 50 is relatively small, such charging power exceeds the input limit Win, and the deterioration of the battery 50 may be promoted.

  When the absolute value of the input limit Win is greater than or equal to the threshold value Wth (step S160), it is determined that the battery 50 has room to accept the power generated by the motor MG1, and the deterioration of the battery 50 is not promoted without suppressing the slip. Steps S170 to S200 are executed, and this routine is terminated. Even if slip occurs in this way, when the absolute value of the input limit Win is equal to or greater than the threshold value Wth, the engine 22 is efficiently operated to perform control to output the required torque Tr * to the ring gear shaft 32a as the drive shaft. It is possible to travel according to the person's intention.

  On the other hand, when the absolute value of the input limit Win is less than the threshold value Wth (step S160), when the slip occurs, it is determined that the battery 50 may not be able to accept the power generated by the motor MG1, and the input of the battery 50 The torque limit Tm2min as a lower limit of the torque that may be output from the motor MG2 using the limit Win is calculated by the equation (4), and the torque that may be output from the motor MG2 based on the rotational angular acceleration α of the motor MG2 is calculated. Torque limit Tm2max is set as an upper limit (step S180). Here, in the embodiment, the torque limit Tm2max is set when the relationship between the rotational angular acceleration α and the torque limit Tm2max is determined in advance and stored in the ROM 74 as a torque upper limit setting map, and the rotational angular acceleration α is given. The corresponding torque limit Tm2max is derived from the map and set. An example of the torque upper limit setting map is shown in FIG. In the embodiment, the torque limit Tm2max is set to decrease as the rotational angular acceleration α increases, that is, as the degree of slip increases. Thus, when the torque limits Tm2min and Tm2max are set, the set temporary torque Tm2tmp is limited by the torque limits Tm2min and Tm2max according to the equation (6) to set the torque command Tm2 * of the motor MG2, and the set target rotational speed Ne *. The target torque Te * and torque commands Tm1 * and Tm2 * are transmitted to the engine ECU 24 and the motor ECU 40, respectively (steps S190 and 200), and this routine is terminated. Thus, by limiting the torque command Tm2 * of the motor MG2 with the torque limit Tm2max that is set to be smaller as the rotational angular acceleration α is larger, the slip can be suppressed. When the slip is suppressed, a sudden decrease in the rotation speed of the ring gear shaft 32a accompanying the cancellation of the slip is suppressed. Therefore, a sudden increase in the rotation speed Nm1 of the motor MG1 is suppressed and the generated power of the motor MG1 is reduced. Charging with excessive power can be suppressed, and deterioration of the battery 50 can be suppressed.

  According to the hybrid vehicle 20 of the embodiment described above, the absolute value of the input limit Win of the battery 50 is the threshold value Wth when a slip occurs when an instruction to turn off the traction control is issued by the TRC off switch 89a. When it is less than this, it is possible to suppress the battery 50 from being charged with excessive power by limiting the torque output from the motor MG <b> 2 and suppressing the slip, thereby suppressing the deterioration of the battery 50. it can. On the other hand, when the absolute value of the input limit Win of the battery 50 is equal to or greater than the threshold value Wth, the control for suppressing such slip is not performed, so that traveling according to the driver's intention can be performed.

  In the hybrid vehicle 20 of the embodiment, as the rotational angular acceleration α of the motor MG2 increases, the torque output from the motor MG2 is limited to suppress slippage due to the idling of the drive wheels 39a and 39b. Such control is not limited to such control. For example, the brake actuator 92 may be actuated to apply braking force to the drive wheels 39a, 39b or a driven wheel (not shown) to suppress slip, The torque output from MG2 may be limited, and the brake actuator 92 may be operated to apply a braking force to the drive wheels 39a and 39b to suppress slip.

  In the hybrid vehicle 20 of the embodiment, the occurrence of slip is determined based on the rotational angular acceleration α of the motor MG2. However, any method may be used as long as it can determine the occurrence of slip, for example, The occurrence of slip may be determined using the wheel speed from the wheel speed sensor attached to the drive wheels 39a and 39b and the vehicle speed V.

  In the hybrid vehicle 20 of the embodiment, the torque limits Tm2min and Tm2max are obtained by the above-described equations (4) and (5) and the torque command Tm2 * of the motor MG2 is set. Any method may be used as long as the torque command Tm1 * Tm2 * of the motors MG1, MG2 is set within the range of the input / output limits Win, Wout of the battery 50 using the motor rotation speed Nm2est.

  In the hybrid vehicle 20 of the embodiment, the motor MG2 is attached to the ring gear shaft 32a as the drive shaft via the reduction gear 35. However, the motor MG2 may be directly attached to the ring gear shaft 32a, or Instead, the motor MG2 may be attached to the ring gear shaft 32a via a transmission such as a 2-speed, 3-speed, or 4-speed.

  In the hybrid vehicle 20 of the embodiment, the power of the motor MG2 is changed by the reduction gear 35 and output to the ring gear shaft 32a. However, as illustrated in the hybrid vehicle 120 of the modification of FIG. May be connected to an axle (an axle connected to wheels 39c and 39d in FIG. 10) different from an axle to which the ring gear shaft 32a is connected (an axle to which the drive wheels 39a and 39b are connected).

  Moreover, it is not limited to what is applied to such a hybrid vehicle, It does not matter as a form of vehicles other than a vehicle. Furthermore, it is good also as a form of the control method of such a vehicle.

Here, the correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, the engine 22 corresponds to an “internal combustion engine”.
The power distribution and integration mechanism 30 corresponds to “three-shaft power input / output means”, the motor MG1 corresponds to “generator”, the motor MG2 corresponds to “motor”, and the battery 50 corresponds to “power storage means”. ,
The TRC off switch 89a corresponds to a “slip suppression instruction switch”, and the hybrid electronic control unit 70 that executes the processing of step S150 of the TRC off-time drive control routine of FIG. Even if the battery 50 is charged / discharged based on the remaining capacity (SOC) of the battery 50 based on the integrated value of the charge / discharge current detected by the current sensor and the battery temperature Tb of the battery 50, which corresponds to “slip detecting means”. The battery ECU 52 that calculates the input / output limits Win and Wout, which are good maximum allowable powers, corresponds to the “input / output limit setting means”, and sets the required torque Tr * based on the accelerator opening Acc and the vehicle speed V of FIG. The electronic control unit for hybrid 70 that executes the process of step S110 of the drive control routine when the TRC is off is “required”. It corresponds to “driving force setting means”, and when slip occurs, and the absolute value of the input limit Win of the battery 50 is equal to or greater than the threshold value Wth, it is used as a drive shaft within the range of the input / output limits Win and Wout of the battery The target rotational speed Ne * and the target torque Te * of the engine 22 are set so as to output the required torque Tr * to the ring gear shaft 32a and the motors MG1, MG2 torque commands Tm1 *, Tm2 * are set as shown in FIG. Slip is suppressed by limiting the torque output from the motor MG2 when the absolute value of the input limit Win of the battery 50 is less than the threshold value Wth in steps S110 to S170, S190, and S200 of the drive control routine when the TRC is off While driving, the required torque Tr * is output to the ring gear shaft 32a as the drive shaft. Steps S110 to S160 and S180 to S200 of the TRC off-time drive control routine of FIG. 2 for setting the target rotational speed Ne * and target torque Te * of the engine 22 and setting the motors MG1, MG2 torque commands Tm1 *, Tm2 *. The hybrid electronic control unit 70 that executes the process, the engine ECU 24 that controls the engine 22 based on the target rotational speed Ne * and the target torque Te *, and the motors MG1 and MG2 based on the torque commands Tm1 * and Tm2 *. The motor ECU 40 corresponds to “control means”. Here, the “internal combustion engine” is not limited to an internal combustion engine that outputs power using a hydrocarbon fuel such as gasoline or light oil, and may be any type of internal combustion engine such as a hydrogen engine. The “three-axis power input / output means” is not limited to the power distribution / integration mechanism 30 described above, but includes four or more shafts using a double pinion type planetary gear mechanism or a combination of a plurality of planetary gear mechanisms. Connected to the three axes of the drive shaft, the output shaft, and the third shaft, such as those connected to the shaft or those having a differential action different from the planetary gear such as a differential gear. As long as the power is input / output to / from the remaining shafts based on the power input / output to / from the power source, any method may be used. The “generator” is not limited to the motor MG1 configured as a synchronous generator motor, and may be any type of generator such as an induction motor that can input and output power. The “motor” is not limited to the motor MG2 configured as a synchronous generator motor, and may be any type of motor as long as it can input and output power to the drive shaft, such as an induction motor. . The “power storage means” is not limited to the battery 50 as a secondary battery, and may be anything as long as it can exchange power with a power power input / output means such as a capacitor and an electric motor. The “slip suppression instruction means” is not limited to the TRC off switch 89a for turning off the traction control by the driver's operation, but the traction control can be turned off by a switch or a pressing operation for turning on / off the torque control. Any button may be used as long as it instructs whether to execute slip suppression control that suppresses slippage due to idling of the drive wheels, such as a button for switching on and off. The “slip detection means” is not limited to the hybrid electronic control unit 70, and may be configured by a plurality of electronic control units. Further, the “slip detection means” is not limited to the hybrid electronic control unit 70 that determines the slip based on the vehicle speed V and the wheel speeds Vl and Vr from the vehicle speed sensor 88, but the wheel speeds Vl and Vr. And detecting slip based on the signal from the wheel speed sensor attached to the driven wheel, detecting slip based on the rotational angular acceleration α of the motor MG2, and so on. It does not matter as long as there is any. The “input / output limit setting means” is not limited to the one that calculates the input / output limits Win and Wout based on the remaining capacity (SOC) of the battery 50 and the battery temperature Tb of the battery 50, but the remaining capacity ( In addition to the SOC) and the battery temperature Tb, the input / output limit is set as the maximum allowable power that allows charging / discharging of the power storage means based on the state of the power storage means, such as that calculated based on the internal resistance of the battery 50, for example. Any object can be used. The “required driving force setting means” is not limited to the one that sets the required torque Tr * based on the accelerator opening Acc and the vehicle speed V, but sets the required torque based only on the accelerator opening Acc. Any device may be used as long as it sets a required driving force required for traveling. The “control means” is not limited to the combination of the hybrid electronic control unit 70, the engine ECU 24, and the motor ECU 40, and may be configured by a single electronic control unit. Further, as the “control means”, when the absolute value of the input limit Win of the battery 50 is greater than or equal to the threshold value Wth, the required torque Tr * is applied to the ring gear shaft 32a as the drive shaft within the range of the input / output limits Win and Wout of the battery 50. To set the target rotational speed Ne * and target torque Te * of the engine 22 so as to travel and set the motor MG1, MG2 torque commands Tm1 *, Tm2 * to control the engine 22 and the motors MG1, MG2. By limiting the torque output from the motor MG2 when the absolute value of the input limit Win of the battery 50 is less than the threshold value Wth, the required torque Tr * is output to the ring gear shaft 32a as the drive shaft while suppressing the slip. The target rotational speed Ne * and target torque Te * of the engine 22 are set so as to run and the motor MG , MG2 torque commands Tm1 *, Tm2 * are not limited to those for controlling engine 22 and motors MG1, MG2, and slip detection is detected when slip suppression control switch is not instructed to execute slip suppression control. When the slip is detected by the means, the internal combustion engine is configured such that when the set input limit is equal to or greater than the predetermined power, the driving force based on the set required driving force is output to the driving shaft without executing the slip suppression control. Controls the generator and motor, and when the set input limit is less than the predetermined power, slip suppression control is executed regardless of the instruction from the slip suppression instruction switch and the driving force based on the set required driving force is driven. As long as it controls an internal combustion engine, a generator, and an electric motor so that it may be output to a shaft, it may be anything. There. Further, as the “control means”, when slip execution is not detected by the slip detection means when the slip suppression instruction switch does not instruct execution of the slip suppression control, the driving force based on the set required driving force is applied to the drive shaft. Any control may be performed such as a control of the internal combustion engine, the generator, and the electric motor so as to be output. As the “control means”, when the slip suppression instruction switch is instructed to execute the slip suppression control, the slip is suppressed by controlling the internal combustion engine, the generator, and the motor so that the slip suppression control is executed. Anything can be used as long as it is controlled. The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the same as that of the embodiment described in the column of means for solving the problem. It is an example for specifically explaining the best mode for doing so, and does not limit the elements of the invention described in the column of means for solving the problem. That is, the interpretation of the invention described in the column of means for solving the problems should be made based on the description of the column, and the examples are those of the invention described in the column of means for solving the problems. It is only a specific example.

  The best mode for carrying out the present invention has been described with reference to the embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the gist of the present invention. Of course, it can be implemented in the form.

  The present invention is applicable to a vehicle manufacturing industry or the like.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 according to an embodiment of the present invention. It is explanatory drawing which shows an example of the relationship between the battery temperature Tb in the battery 50, and the input / output restrictions Win and Wout. It is explanatory drawing which shows an example of the relationship between the remaining capacity (SOC) of the battery 50, and the correction coefficient of input / output restrictions Win and Wout. It is a flowchart which shows an example of the drive control routine at the time of TRC OFF performed by the electronic control unit for hybrids of an Example. It is explanatory drawing which shows an example of the map for request | requirement torque setting. It is explanatory drawing which shows a mode that an example of the operating line of the engine 22, the target rotational speed Ne *, and the target torque Te * are set. FIG. 3 is an explanatory diagram showing an example of a collinear diagram showing a dynamic relationship between the number of rotations and torque in a rotating element of a power distribution and integration mechanism 30 when traveling with power output from an engine 22; It is a collinear diagram showing an example of the relationship between the rotational speeds of the rotating elements of the power distribution and integration mechanism 30 when slipping occurs due to idling of the drive wheels 39a and 39b. It is explanatory drawing which shows an example of the map for torque upper limit setting. FIG. 11 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 120 according to a modification.

Explanation of symbols

  20,120 Hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 24a CPU, 24b ROM, 24c RAM, 26 crankshaft, 28 damper, 30 power distribution integrated mechanism, 31 sun gear, 32 ring gear, 32a ring gear Shaft, 33 pinion gear, 34 carrier, 35 reduction gear, 39a, 39b drive wheel, 39c, 39d wheel, 40 motor electronic control unit (motor ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 50 battery, 51 Temperature Sensor, 52 Battery Electronic Control Unit (Battery ECU), 54 Power Line, 60 Gear Mechanism, 62 Differential Gear, 70 Hybrid Electronic Control Unit, 72 CPU, 74 ROM, 7 6 RAM, 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor, 88 vehicle speed sensor, 89a TRC off switch, 89b, 89c wheel speed Sensor, 90 Brake master cylinder, 92 Brake actuator, 94 Brake electronic control unit (brake ECU), 96a-96d Brake wheel cylinder, MG1, MG2 motor.

Claims (4)

An internal combustion engine;
Power is applied to the remaining shafts based on power input / output to / from any two of the three shafts connected to three shafts of the output shaft of the internal combustion engine, a drive shaft connected to the drive wheels, and a third shaft. 3-axis power input / output means for input / output;
A generator capable of inputting and outputting power to the third shaft;
An electric motor capable of outputting power to the drive shaft;
Power storage means capable of exchanging electric power with the generator and the motor;
A slip suppression instruction switch for instructing whether or not to execute slip suppression control for suppressing slip due to idling of the drive wheel;
Slip detecting means for detecting slip due to idling of the drive wheel;
Input limit setting means for setting an input limit as the maximum allowable power when charging the power storage means based on the state of the power storage means;
Requested driving force setting means for setting a requested driving force required for the drive shaft based on an operation of the driver;
When slip is detected by the slip detection means when execution of the slip suppression control is not instructed by the slip suppression instruction switch, the slip suppression control is executed when the set input limit is a predetermined power or more. Without controlling the internal combustion engine, the generator and the motor so that a driving force based on the set required driving force is output to the driving shaft, and the set input limit is less than the predetermined power. In some cases, the slip suppression control is executed regardless of an instruction from the slip suppression instruction switch, and the driving force based on the set required driving force is output to the drive shaft. Control means for controlling the electric motor;
A vehicle comprising:   The vehicle according to claim 1, wherein the control unit is a unit that executes control for limiting power output from the electric motor to the drive shaft as the slip suppression control. The vehicle according to claim 1 or 2,
A braking force applying means capable of applying a braking force to the drive wheel;
The control means is means for executing a control in which a braking force is applied to the drive wheel by the braking force applying means as the slip suppression control. An internal combustion engine, an output shaft of the internal combustion engine, a drive shaft connected to a drive wheel, and a third shaft, which are connected to three shafts and the remaining power based on power input / output to / from any two of the three shafts 3-axis power input / output means for inputting / outputting power to / from the shaft, a generator capable of inputting / outputting power to / from the third shaft, an electric motor capable of outputting power to the drive shaft, the generator and the electric motor And a power storage means capable of exchanging electric power, and a slip suppression instruction switch for instructing whether or not to execute slip suppression control for suppressing slip due to idling of the drive wheels,
Input limit setting means for setting an input limit as the maximum allowable power when charging the power storage means based on the state of the power storage means;
Requested driving force setting means for setting a requested driving force required for the drive shaft based on an operation of the driver;
When slippage due to idling of the drive wheel occurs when the slip suppression instruction switch does not instruct execution of the slip suppression control, the slip suppression control is executed when the set input limit is equal to or greater than a predetermined power. Without controlling the internal combustion engine, the generator and the motor so that a driving force based on the set required driving force is output to the driving shaft, and the set input limit is less than the predetermined power. In some cases, the slip suppression control is executed regardless of an instruction from the slip suppression instruction switch, and the driving force based on the set required driving force is output to the drive shaft. A vehicle control method for controlling an electric motor.

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