JP2015074417A - Control device of hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device of a hybrid vehicle which suppresses vibration of a vehicle upon backward traveling.SOLUTION: When an absolute value of a propeller shaft demand torque TP* exceeds an MG torque minimum value Tm2 min upon backward traveling according to EV traveling mode (S120), the propeller shaft demand torque TP* performs motoring of an engine with a predetermined torque T1 by means of a first motor, at the same time, a second motor is controlled such that a torque within the range of the MG2 torque minimum value Tm2 min is outputted so as to become less than a propeller shaft torque upon a prescribed motoring operating the driving shaft (S150), the predetermined torque T1 is preset to a torque instruction Tm1* (S160), a torque instruction Tm2* of the second motor is preset such that the propeller shaft demand torque TP* is outputted to the driving shaft (S 180) and the first and second motors are controlled (S190). Thereby, vibration of the vehicle due to low rotation number of the engine upon backward traveling can be suppressed.

Description

  The present invention relates to a control device for a hybrid vehicle, and more specifically, three rotation elements are connected to an engine, a first motor, a drive shaft coupled to an axle, an output shaft of the engine, and a rotation shaft of the first motor. The present invention relates to a control device for a hybrid vehicle that is mounted on a hybrid vehicle including a planetary gear and a second motor having a drive shaft connected to a rotation shaft and controls at least the first motor.

  Conventionally, this type of hybrid vehicle control device includes an engine, a three-shaft power split mechanism connected to a crankshaft as an output shaft of the engine, and a first power generating mechanism connected to the power split mechanism. It is mounted on a hybrid vehicle having a motor generator and a second motor generator connected to a ring gear shaft as a drive shaft connected to the power split mechanism, so that the second motor generator can obtain a driving force during reverse travel. One that controls a two-motor generator has been proposed (see, for example, Patent Document 1). In this control device, when it is detected that the rear wheel has passed the step during reverse travel, the motor is engineed by the first motor generator, and the driving force from the second motor generator is combined with the driving force from the first motor generator. Driving force is also applied to the driving shaft to increase the torque to the front wheels, thereby increasing the driving force for overcoming the step at an appropriate timing.

JP 2013-103593 A

  In the control device described above, when the engine is motored by the first motor generator, if the engine speed is low, the vehicle will vibrate. It is desirable to suppress such vibrations because passengers feel uncomfortable.

  The main object of the hybrid vehicle control device of the present invention is to suppress vehicle vibration during reverse travel.

  The control apparatus for a hybrid vehicle of the present invention employs the following means in order to achieve the above-described main object.

The hybrid vehicle control device of the present invention comprises:
An engine, a first motor, a drive shaft connected to an axle, a planetary gear in which three rotation elements are connected to an output shaft of the engine and a rotation shaft of the first motor, and a rotation shaft connected to the drive shaft A hybrid vehicle control device that is mounted on a hybrid vehicle including the second motor and controls at least the first motor,
Torque that the absolute value of the drive shaft required torque required for the drive shaft can be output from the second motor while the engine is stopped and torque is output from the second motor to travel backward. When the absolute value of the minimum value is exceeded, the first motor is controlled by motoring by the first motor so that the engine speed becomes equal to or higher than a predetermined speed at which vibration of the engine is suppressed. The gist.

  In the hybrid vehicle according to the present invention, the absolute value of the drive shaft required torque required for the drive shaft is calculated from the second motor while the engine is stopped and the torque is output from the second motor to travel backward. When the absolute value of the minimum torque that can be output is exceeded, motoring by the first motor controls the first motor so that the engine speed becomes equal to or higher than a predetermined speed at which engine vibration is suppressed. Thereby, the rotation speed of the engine can be made equal to or higher than the predetermined rotation speed, and vibration of the vehicle during reverse travel can be suppressed.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 as an embodiment of the present invention. 4 is a flowchart showing an example of a reverse travel motor control routine executed by the HVECU 70 of the hybrid vehicle 20; It is explanatory drawing which shows an example of the map for MG2 torque minimum value setting. It is explanatory drawing which shows an example of the collinear diagram which shows the dynamic relationship between the rotation speed and torque in the rotation element of the planetary gear 30 at the time of reverse drive, motoring the engine 22 with the motor MG1. It is explanatory drawing which shows an example of the time change of the peller shaft torque TP in the conventional control. It is explanatory drawing which shows an example of the time change of the peller shaft torque TP in the control of an Example.

  Next, the form for implementing this invention is demonstrated using an Example.

  FIG. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 as an embodiment of the present invention. In the hybrid vehicle 20 of the embodiment, as shown in the figure, a carrier is connected to an engine 22 that outputs power using gasoline or light oil as a fuel, a crankshaft 26 of the engine 22, and a differential gear 32 is connected to drive wheels 34 a and 34 b. A planetary gear 30 in which a ring gear is connected to a drive shaft (peller shaft) 36 connected via a motor, a motor MG1 configured as, for example, a synchronous generator motor and having a rotor connected to a sun gear of the planetary gear 30, and a synchronous generator motor, for example. And a motor MG2 having a rotor connected to the drive shaft 36 via a reduction gear 35, inverters 41 and 42 for driving the motors MG1 and MG2 by switching of a plurality of switching elements (not shown), Next battery is configured as an inverter It includes a battery 50 for exchanging the motor MG1, MG2 and power through the 1,42, and HVECU70 for controlling the entire vehicle, a.

  The HVECU 70 is configured as a microprocessor centered on a CPU (not shown). In addition to the CPU, the HVECU 70 includes a ROM for storing a processing program, a RAM for temporarily storing data, an input / output port, and a communication port (not shown). Prepare. The HVECU 70 includes an ignition signal from the ignition switch 80, a shift position SP from the shift position sensor 82 that detects the operation position of the shift lever 81, and an accelerator opening degree from the accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83. Operation control of the engine 22 such as Acc, the brake pedal position BP from the brake pedal position sensor 86 that detects the depression amount of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 88, and signals from various sensors that detect the state of the engine 22 Installed between the terminals of the battery 50, signals necessary for driving and controlling the motors MG1, MG2, such as signals from a rotational position detection sensor (not shown) for detecting the rotational position of the rotor of the motors MG1, MG2. Voltage not shown Such as signals required for control of the inter-terminal voltage such as a battery 50 from capacitors is input via the input port. The HVECU 70 outputs an operation control signal for controlling the operation of the engine 22 and a switching control signal for the inverters 41 and 42. Further, the HVECU 70 calculates the remaining capacity SOC of the battery 50 (the ratio of the charged amount of the battery 50 to the maximum value of the charged amount that can be charged in the battery 50).

  Further, in the hybrid vehicle 20 of the embodiment, as the shift position SP of the shift lever 81, a parking range (P range) used during parking, a reverse range for reverse travel (R range), a neutral neutral range (N range), forward In addition to the normal driving range (D range) for driving, the setting of the driving force when the accelerator is on is the same as the D range, but the braking force that is applied to the vehicle when the accelerator is off during driving is set larger than the D range. A sequential shift range (S range) having a brake range (B range), an upshift instruction range, and a downshift instruction range is prepared.

  In the hybrid vehicle 20 of the embodiment configured as described above, a hybrid travel mode (HV travel mode) that travels with the operation of the engine 22 or an electric travel mode (EV travel mode) that travels while the operation of the engine 22 is stopped. Run.

  When traveling in the HV traveling mode, the HVECU 70 uses the propeller shaft required torque TP * (a positive value when traveling in the forward direction) required for the drive shaft 36 when traveling based on the accelerator opening Acc and the vehicle speed V. The rotation speed and vehicle speed obtained by dividing the rotation speed Nr of the drive shaft 36 (for example, the rotation speed Nm2 of the motor MG2 by the reduction ratio (reduction ratio) RR of the reduction gear 35) to the set required torque of the peller shaft TP *. The driving power Pdrv * required for driving is calculated by multiplying V by the number of revolutions obtained by multiplying the conversion factor, and charging / discharging of the battery 50 based on the storage ratio SOC of the battery 50 is calculated from the calculated driving power Pdrv *. The required power Pe * required for the vehicle is set by subtracting the required power Pb * (a positive value when discharging from the battery 50). Then, the target rotational speed Ne *, the target torque Te *, and the torque commands of the motors MG1 and MG2 are output so that the required power Pe * is output from the engine 22 and the peller shaft required torque TP * is output to the drive shaft 36. Tm1 *, Tm2 * are set, and the intake air amount control, fuel injection control, ignition control, etc. of the engine 22 are performed so that the engine 22 is operated by the target rotational speed Ne * and the target torque Te *, and the motors MG1, MG2 Is controlled by the torque commands Tm1 * and Tm2 * to perform switching control of the switching elements of the inverters 41 and 42. During traveling in the HV traveling mode, when the stop condition of the engine 22 is satisfied, for example, when the required power Pe * is less than the stop threshold value Pstop, the operation of the engine 22 is stopped and the traveling in the EV traveling mode is performed. Transition.

  During travel in the EV travel mode, the HVECU 70 sets the propeller shaft request torque TP * based on the accelerator opening Acc and the vehicle speed V, sets a value 0 to the torque command Tm1 * of the motor MG1, and also uses the propeller shaft request torque. The torque command Tm2 * of the motor MG2 is set so that TP * is output to the drive shaft 36, and switching control of the switching elements of the inverters 41 and 42 is performed so that the motors MG1 and MG2 are driven by the torque commands Tm1 * and Tm2 *. Do. When traveling in the EV traveling mode, the engine 22 is started when the starting condition of the engine 22 is satisfied, such as when the required power Pe * calculated in the same manner as traveling in the HV traveling mode reaches or exceeds the starting threshold value Pstart. And it transfers to driving | running | working in HV driving mode.

  In the hybrid vehicle 20 of the embodiment, when the shift position SP is in the R range, basically, the operation of the engine 22 is stopped and the traveling in the EV traveling mode described above is performed.

  Next, the operation of the hybrid vehicle 20 of the embodiment thus configured, particularly the operation when the shift position SP is in the R range will be described. FIG. 2 is a flowchart showing an example of the reverse travel motor control routine executed by the HVECU 70 of the hybrid vehicle 20. This routine is repeatedly executed at predetermined time intervals (for example, every several msec) while the shift position SP is in the R range and the vehicle is traveling in the EV traveling mode in the backward direction. During the execution of this routine, the intake air amount control, fuel injection control, ignition control, and the like of the engine 22 are stopped, that is, the operation of the engine 22 is stopped.

  When the reverse running motor control routine is executed, the HVECU 70 sets the propeller shaft required torque TP * based on the accelerator opening Acc and the vehicle speed V (step S100), and the motor based on the rotational speed Nm2 of the motor MG2. MG2 torque minimum value Tm2min is set as the minimum value of torque that can be output from MG2 (maximum value as an absolute value) (step S110). Here, in the embodiment, the MG2 torque minimum value Tm2min is determined in advance as a MG2 torque minimum value setting map by storing the relationship between the rotational speed Nm2 of the motor MG2 and the MG2 torque minimum value, and is stored in the motor VECU 70. When the rotation speed Nm2 is given, the corresponding MG2 torque minimum value is derived and set from the stored map. FIG. 3 shows an example of the MG2 torque minimum value setting map.

  Subsequently, the torque (= Tm2min × RR) acting on the drive shaft 36 by outputting the MG2 torque minimum value Tm2min from the motor MG2 is compared with the required propeller shaft torque TP * (step S120). Since the MG2 torque minimum value Tm2min is the minimum value of the torque that can be output from the motor MG2, whether or not the processing of step S110 can cover all the required shaft axis torque TP * with the torque from the motor MG2 during reverse travel. This is a process for determining whether or not.

  When the propeller shaft required torque TP * is equal to or greater than the MG torque minimum value Tm2min (because both the propeller shaft required torque TP * and the MG torque minimum value Tm2min are negative values when traveling in the reverse direction) When the absolute value of TP * is equal to or smaller than the absolute value of MG torque minimum value Tm2min (step S120), it is determined that the propeller shaft required torque TP * can be entirely covered by the torque from motor MG2, and the motor A value 0 is set in the torque command Tm1 * of MG1 (step S130), and a value obtained by dividing the required shaft torque TP * by the reduction ratio RR is set as the motor torque command Tm2 * (step S140). The switching elements of the inverters 41 and 42 are switched so that MG2 is driven by the torque commands Tm1 * and Tm2 *. By performing ring control (step S190), and terminates this routine. By such processing, the vehicle can travel in the EV travel mode described above.

  When the peller shaft required torque TP * is less than the MG torque minimum value Tm2min (when the absolute value of the peller shaft required torque TP * exceeds the absolute value of the MG torque minimum value Tm2min) (step S120), the peller shaft It is determined that the required torque TP * cannot be entirely covered by the torque from the motor MG2, and then the motor MG2 is motored with the predetermined torque T1 by the motor MG1 calculated by the following equation (1). To MG2 torque minimum value Tm2min, Peller shaft torque minimum value TPmin, which is the minimum value of torque acting on drive shaft 36 when torque is output, is compared with peller shaft request torque TP * (step S150). Here, the predetermined torque T1 increases the rotational speed of the engine 22 to a rotational speed that does not cause vibration due to the low rotational speed of the engine 22 when the motor 22 is motored by the motor MG1 (for example, 1000 rpm). A predetermined torque is used as the torque of the motor MG1. In the equation (1), ρ is the gear ratio ρ of the planetary gear 30 (the number of teeth of the sun gear / the number of teeth of the ring gear).

 TPmin = Tm2min × RR-T1 / ρ (1)

  FIG. 4 shows an example of a collinear diagram showing the mechanical relationship between the rotational speed and torque of the rotating element of the planetary gear 30 when the motor MG1 is traveling backward while motoring the engine 22. 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 rotation speed Nr of the ring gear of the planetary gear 30 obtained by dividing the number Nm2 by the reduction ratio RR 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 drive shaft 36 and the torque Tm2 output from the motor MG2 acts on the drive shaft 36 via the reduction gear 35. Torque. That is, the process of step S150 is performed by the torque applied to the drive shaft 36 when the motor MG1 outputs the torque within the range of the MG2 torque minimum value Tm2min while motoring the engine 22 with the predetermined torque T1. This process determines whether or not the required torque TP * can be covered.

  When the required peller shaft torque TP * is equal to or greater than the minimum peller shaft torque value TPmin (step S150), the motor MG2 motors the engine 22 with the predetermined torque T1 while the motor MG2 controls the torque within the range of the MG2 torque minimum value Tm2min. It is judged that the torque acting on the drive shaft 36 when it is output can cover all the required torque of the propeller shaft TP *, the predetermined torque T1 is set in the torque command Tm1 * (step S160), and the following equation (2) ) Is used to set the torque command Tm2 * of the motor MG2 so that the required propeller shaft torque TP * is output to the drive shaft 36 (step S180), and the motors MG1 and MG2 are driven by the torque commands Tm1 * and Tm2 *. The switching control of the switching elements of the inverters 41 and 42 is performed (step S19). ), And it ends the present routine. With this control, the motor MG1 can drive the engine 22 with the predetermined torque T1 and output the propeller shaft required torque TP * to the drive shaft 36 to travel backward. Here, the predetermined torque T1 is the torque of the motor MG1 that can increase the rotational speed of the engine 22 to such an extent that vibration due to the low rotational speed of the engine 22 does not occur when the engine 22 is motored by the motor MG1. Generation of vibration due to the low rotation speed of the engine 22 can be suppressed, and generation of vibration of the vehicle can be suppressed.

  Tm2 * = (TP * + Tm1 * / ρ) / RR (2)

  When the peller shaft required torque TP * is less than the minimum peller shaft torque value TPmin (step S150), the motor MG2 motors the engine 22 with the predetermined torque T1, and a torque within the range of the motor MG2 to the MG2 torque minimum value Tm2min. When it is determined that the torque acting on the drive shaft 36 cannot be covered by the torque acting on the drive shaft 36 and the MG2 torque minimum value Tm2min is output from the motor MG2, the propeller shaft required torque TP * is The torque command Tm1 * of the motor MG1 is set using the following equation (3) to be output to the motor 36 (step S170), and the propeller shaft required torque TP * is output to the drive shaft 36 using the above equation (2). Motor MG2 torque command Tm2 * is set (step S180), and motors MG1, MG2 are set. The torque command Tm1 *, performs a switching control of the switching elements of the inverters 41 and 42 to be driven by Tm2 * (step S190), and terminates this routine. In step S180, the torque command Tm2 * of the motor MG2 is set to the MG2 torque minimum value Tm2min. By such control, the propeller shaft required torque TP * is output to the drive shaft 36 by the torque output to the drive shaft 36 by the motoring of the engine 22 by the motor MG1 and the torque (minimum torque Tm2min) from the motor MG2, and the reverse drive You can travel.

  Tm1 * =-(TP * -Tm2min × RR) × ρ (3)

  FIG. 5 is an explanatory view showing an example of a time change of the peller shaft torque TP in the conventional control. Here, in the “conventional control”, when the propeller shaft required torque TP * becomes less than the MG torque minimum value Tm2min when the vehicle is traveling backward in the EV traveling mode, the above-described equations (2) and (3) Are used to set torque commands Tm1 * and Tm2 * for the motors MG1 and MG2, and the torque required for the propeller shaft TP * is determined by the torque output to the drive shaft 36 by the motoring of the engine 22 by the motor MG1 and the torque from the motor MG2. The motors MG1 and MG2 are controlled so as to be output to the drive shaft 36. In the drawing, the hatched portion indicates a region where the motor MG1 is controlled so that torque is output to the drive shaft 36 by motoring of the engine 22 by the motor MG1. In the conventional control, as shown in the figure, when the propeller shaft required torque TP * is less than the MG torque minimum value Tm2min when the vehicle is traveling backward in the EV travel mode, motoring of the engine 22 by the motor MG1 is started. At this time, since the difference between the required torque TP * of the shaft and the torque obtained by multiplying the minimum MG torque value Tm2min by the reduction ratio RR is small for a while, the engine 22 is controlled at a relatively low speed (for example, about 200 prm). Therefore, the period during which the vibration of the engine 22 and thus the vibration of the vehicle is felt becomes longer, and the passenger may feel uncomfortable.

  FIG. 6 is an explanatory diagram showing an example of the change over time of the peller shaft torque TP in the control of the embodiment. In the diagram, the hatched portion indicates that torque is output to the drive shaft 36 by the motoring of the engine 22 by the motor MG1. The region where the motor MG1 is controlled is shown. In the control of the embodiment, when the propeller shaft required torque TP * becomes less than the MG torque minimum value Tm2min during reverse traveling in the EV driving mode (step S120), the peller shaft required torque TP * becomes the peller shaft torque minimum value TPmin. Until it becomes less (step S150), the above-described processing of steps S160, S180, and S190 is executed, and the motor MG1 travels backward while motoring the engine 22 at a predetermined torque T1 (time t1 to t2). By such control, the rotational speed of the engine 22 can be quickly increased to a rotational speed at which vibration does not occur, and the vibration of the engine 22 and thus the vibration of the vehicle can be suppressed.

  In this way, when the motor 22 is being motored, if the peller shaft required torque TP * becomes less than the minimum peller shaft torque value TPmin (step S150), the motor MG2 motors the engine 22 with the predetermined torque T1 by the motor MG1. When the torque within the range of MG2 torque minimum value Tm2min is output, the torque acting on the drive shaft 36 cannot be covered by the torque required for the propeller shaft TP *. Therefore, the processing of steps S170 to S190 is executed, The motor MG1 is driven by the torque command Tm1 * set by the equation (3), and the torque output to the drive shaft 36 by the motoring of the engine 22 and the torque from the motor MG2 (Tm2min) The vehicle travels backward by outputting TP * to the drive shaft 36 (time t2 to t3). As a result, the vehicle can travel backward with the propeller shaft request torque TP *.

  Then, when the propeller shaft required torque TP * becomes equal to or larger than the minimum propeller shaft torque value TPmin (step S150), the processing of steps S170 to S190 described above is executed, and the motor 22 is motored with the predetermined torque T1. (Time t3 to t4). By such control, the rotation speed of the engine 22 can be increased to a rotation speed at which vibration does not occur, and vibrations of the engine 22 and thus vibrations of the vehicle can be suppressed.

  In the hybrid vehicle 20 of the embodiment described above, when the propeller shaft required torque TP * is less than the MG torque minimum value Tm2min when the vehicle is traveling backward in the EV driving mode (the absolute value of the peller shaft required torque TP * is When the MG torque minimum value Tm2min is exceeded), the motor MG1 performs motoring of the engine 22 at the predetermined torque T1 until the peller shaft required torque TP * becomes smaller than the peller shaft torque minimum value TPmin. By outputting * to the drive shaft 36 and traveling backward, vibration of the hybrid vehicle 20 can be suppressed.

  In the embodiment, when the required peller shaft torque TP * is less than the minimum MG torque value Tm2min, the required peller shaft torque TP * is compared with the minimum peller shaft torque value TPmin (step S150), When the required torque TP * is less than the minimum value TPmin of the shaft axis torque, the shaft output by the torque output from the motor MG2 to the drive shaft 36 by the motoring of the engine 22 by the motor MG1 and the torque from the motor MG2 (minimum torque Tm2min). Although the motors MG1 and MG2 are controlled so that the required torque TP * is output to the drive shaft 36 (steps S170 to S190), when the peller shaft required torque TP * is less than the MG torque minimum value Tm2min, a step is performed. Without executing the processing of S150 and S170, the motor MG1 performs the predetermined torque. It may be controlled motors MG1, MG2 to reverse running by outputting a propeller shaft torque demand TP * to the drive shaft 36 with motoring of the engine 22 at T1.

  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 “engine”, the motor MG1 corresponds to “first motor”, the motor MG2 corresponds to “second motor”, the planetary gear 30 corresponds to “planetary gear”, and the HVECU 70 It corresponds to “control means”.

  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. Therefore, the elements of the invention described in the column of means for solving the problems are not limited. 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.

  As mentioned above, although the form for implementing this invention was demonstrated using the Example, this invention is not limited at all to such an Example, In the range which does not deviate from the summary of this invention, it is with various forms. Of course, it can be implemented.

  The present invention can be used in the manufacturing industry of control devices for hybrid vehicles.

  20 hybrid vehicle, 22 engine, 26 crankshaft, 30 planetary gear, 32 differential gear, 34a, 34b drive wheel, 35 reduction gear, 36 drive shaft, 41, 42 inverter, 50 battery, 70 HVECU, 80 ignition switch, 81 shift lever , 82 Shift position sensor, 83 Accelerator pedal, 84 Accelerator pedal position sensor, 85 Brake pedal, 86 Brake pedal range sensor, 88 Vehicle speed sensor, MG1, MG2 motor.

Claims (1)

An engine, a first motor, a drive shaft connected to an axle, a planetary gear in which three rotation elements are connected to an output shaft of the engine and a rotation shaft of the first motor, and a rotation shaft connected to the drive shaft A hybrid vehicle control device that is mounted on a hybrid vehicle including the second motor and controls at least the first motor,
Torque that the absolute value of the drive shaft required torque required for the drive shaft can be output from the second motor while the engine is stopped and torque is output from the second motor to travel backward. When the absolute value of the minimum value is exceeded, the first motor is controlled by motoring by the first motor so that the engine speed becomes equal to or higher than a predetermined speed at which vibration of the engine is suppressed. A control device for a hybrid vehicle.

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