JP4834519B2 - Vehicle drive source control device - Google Patents

Description

  The present invention relates to a drive source control device for a vehicle, and more particularly to a drive source control device for a vehicle including a motor in addition to an engine as a drive source.

  Patent Document 1 discloses an automatic transmission capable of transmitting the kinetic energy of a vehicle traveling in a repulsive manner to an internal combustion engine and cranking (pushing and starting) the internal combustion engine. Further, in Patent Document 2, in order to suppress a shock felt by a reduction in vehicle speed when the kinetic energy of the vehicle is transmitted to the internal combustion engine, an assist driving force is output to the rotating device (motor generator), and the kinetic energy is output. It has been proposed to suppress a decrease in vehicle speed due to loss of the vehicle.

Japanese Utility Model Publication No. 64-53659 JP 2004-190498 A

  However, when the engine is cranked and started using kinetic energy while the vehicle is running, there is a loss of kinetic energy while cranking, as shown in FIG. Since the engine output torque is applied when it comes, there is a problem that torque shock cannot be absorbed simply by adding motor assist as in Patent Document 2.

  Further, the load for rotating the engine at the time of cranking is not constant and varies depending on the increase in the engine speed and the compression / expansion of the piston as shown in FIG. 5, resulting in a cyclic load on the wheels. There is a problem of hanging.

  The present invention has been made in view of the above-described circumstances, and is a vehicle drive source control device that can suppress a shock when the engine is cranked and switched to engine running by using kinetic energy during vehicle running. Is to provide.

According to a first aspect of the present invention, there is provided a vehicle drive source control device that controls a motor that drives a vehicle and an engine that is controlled to stop according to the running state of the vehicle, and uses the kinetic energy of the vehicle. Engine starting means for starting the engine in a stopped state by cranking, torque fluctuation estimating means for estimating the torque fluctuation caused to the wheels during cranking of the engine, and the motor so as to cancel the estimated torque fluctuation A torque fluctuation canceling means for adjusting the command torque to the wheel, and transmitting power from the engine to the wheels, the engine, clutch, and transmission from the upstream side to the downstream side of the power transmission system The motor is arranged from the downstream side in the power transmission system via the transmission and the clutch. Is capable of transmitting power to the engine Te, the engine starting means is in the engine stop state, when the accelerator opening degree exceeds a predetermined value, regardless of the vehicle speed, to start the cranking activation of engine, the torque The fluctuation estimation means is provided with a vehicle drive source control device that estimates both torque loss due to cranking of the engine and torque generated after engine startup.

  According to a second aspect of the present invention, the vehicle drive source control apparatus is characterized in that both a torque loss required for engine cranking and a generated torque after starting the engine are estimated and offset. A vehicle drive source control device is provided.

  According to a third aspect of the present invention, in the vehicle drive source control apparatus, the torque fluctuation pattern is estimated based on the engine rotation cycle and the top dead center of the engine piston. A vehicle drive source control device is provided.

  According to the present invention, it is possible to start the engine without causing a shock in the motor running state and smoothly shift to engine running.

  Next, the best mode for carrying out the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a hybrid vehicle to which the present invention can be applied. First, referring to FIG. 1, an engine represented by an internal combustion engine (hereinafter also referred to as “ENG”) 11 and two types of prime movers, that is, MG 12 driven by electricity stored in a battery 19, are arranged in parallel. It is arranged in such a manner that the wheels can be driven.

  The output of the engine 11 is transmitted to the transmission 13, and then transmitted to the axle shafts 15, 15 ′ and the drive wheels 16, 16 ′ via a differential device (differential) 14 that is an output unit to drive the vehicle. To do. Similarly, the output of the MG 12 can drive the vehicle via a differential device (differential) 14.

  The hybrid vehicle shown in FIG. 1 has an HV-ECU 21 (Hybrid Electronic Control Unit) that controls the entire vehicle, an MG-ECU and an inverter 22 that commands the MG 12 to drive or regenerate, and a stop and combustion state of the engine 11. An EG-ECU 23 to be controlled, a clutch actuator 17 incorporated in the transmission 13, an AMT-ECU 24 that controls the shift actuator 18 to perform an optimum shift, and a battery ECU 25 that manages the state of charge of the battery 19 are provided.

  The HV-ECU 21 functions as an engine starting unit, a torque variation estimating unit, and a torque variation canceling unit, and controls and manages the MG-ECU, the inverter 22, the EG-ECU 23, and the battery ECU 25 in response to the driver's will of travel. Further, the EG-ECU 23 cooperates with the AMT-ECU 24 to produce the best combustion state, and performs fuel control at the time of starting the engine by pushing by the kinetic energy of the starter 20 or the vehicle. In addition, an indicator 26 that displays the speed of the vehicle is provided in the driver's seat.

  FIG. 2 is a skeleton diagram showing a schematic configuration (fourth speed state) of the drive mechanism of the hybrid vehicle. First, the structure on the transmission 13 side will be described. A flywheel 32 is fixed to the end of the output shaft 31 of the engine 11. A clutch element 33 is attached to the flywheel 32, and is engaged and disengaged by the clutch actuator 17. It is possible. The driven member of the clutch is integrally attached to the input shaft 34 of the transmission 13 in the rotational direction by a spline or the like. On the input shaft 34, drive gears of 1st 35, Rev 36, 2nd 37 are integrally formed in order from the clutch side, and further, drive gears of 3rd 38, 4th 39, 5th 40, 6th 41 are rotatably mounted. Further, the output shaft 42 of the transmission 13 is provided in parallel with the input shaft 34, and the 1st43, 2nd44 driven gears are rotatable at positions where the gears mesh with the respective gears, and the 3rd45, 4th46, 5th47, 6th48 driven The gear is mounted integrally. A drive gear 49 that meshes with the ring gear 70 of the differential (differential) 14 is integrally attached to the clutch-side end of the output shaft 42 of the transmission 13. Furthermore, a shaft 50 parallel to the input shaft 34 of the transmission 13 is provided on the transmission 13 side, and a Rev idler gear 51 is rotatably mounted. The Rev idler gear 51 is also movable in the axial direction and does not mesh with the Rev drive gear 36 at the clutch side position (thick solid line), but can mesh with the Rev drive gear 36 at the position on the 6th drive gear 41 side (thin line). It has become.

  Hub members 52, 53, and 54 that are fixedly rotated with the respective shafts are provided between the driving gears and the driven gears of the input shaft 34 and the output shaft 42 of the transmission 13. Each hub member has an engaging means such as a spline on the outer periphery, and further meshes with sleeve members 55, 56, 57 provided on the outer periphery, and the sleeve is moved in the axial direction (left and right in the figure) by the speed change actuator 18. The left gear and the right gear mesh with the spline and transmit power, and the neutral state does not mesh with any gear. In FIG. 2, the sleeve member 56 moves to the left and is in the fourth speed state. Further, the sleeve member 55 between the first shaft 43 and the second shaft 44 of the output shaft 42 is further provided with a gear 58 at a portion extending to the outer peripheral portion, and the gear 58 is in a state where the Rev idler gear 51 is engaged with the Rev drive gear 36. 51, and is in two states, a neutral state and a Rev drive state.

  As described above, the driving force of the engine 11 is engaged with the clutch by the clutch actuator 17, and is transmitted to the first drive gear 49 at the end of the output shaft 42 according to the speed ratio selected by the speed change actuator 18.

  On the other hand, the driving force output by the MG 12 is transmitted to a driving gear 61 provided integrally at the end of the MG output shaft 60. An intermediate reduction shaft 62 disposed in parallel with the MG output shaft 60 includes a driven gear 63 that meshes with the driving gear 61, a second drive gear 64 that meshes with the ring gear 70 of the differential device (differential) 14, , And the driving force of the MG 12 is transmitted to the second driving gear 64 at a predetermined reduction ratio.

  With the above configuration, the output of the engine 11 and the MG 12 is transmitted to the ring gear 70 by the HV-ECU 21 (Hybrid Vehicle Electronic Control Unit), and the difference in the number of revolutions is reduced as necessary via the differential device (differential) 14. After absorption, the axle shafts 15, 15 'and the drive wheels 16, 16' are driven.

  The MG 12 has both functions of a power running state in which electric power is received and converted into driving force, and a regenerative state in which driving force is converted into electric power. The magnetic force generated in the stator member 66 by the three-phase electric power is By passing a large amount of current at a position optimal for returning through the iron portion, control is performed so that efficient conversion including generation of driving force and control of the rotation direction can be performed.

  A resolver 65 is attached to the opposite side of the output shaft 60 of the MG 12 as a rotation detection device. The resolver 65 detects a relative angle between the stator member 66 around which the coil of the MG 12 is wound and the rotor member 67 that rotates integrally with the MG output shaft 60, and can be used as a resolver signal. For example, the resolver signal can be used as the vehicle speed by converting the numerical value depending on the number of poles of the MG 12 and the gear ratio on the MG 12 side.

  Subsequently, control of the drive source in the hybrid vehicle having the above configuration will be described in detail with reference to the drawings. FIG. 3 is a flowchart showing processing performed at predetermined time intervals in the HV-ECU 21.

  Referring to FIG. 3, first, the HV-ECU 21 checks whether or not the vehicle speed is equal to or higher than the engine startable speed (step S001). Here, if the vehicle speed is less than the engine startable speed, the engine cranking start is not performed (NO in step S001).

  On the other hand, when the vehicle speed is equal to or higher than the engine startable speed, the HV-ECU 21 further checks whether or not the engine is requested to start (step S002). Here, if the engine start request condition is satisfied when the engine is stopped and the motor is running, such as during initial running or eco-run (economy & ecology running), the processing from step S003 onward is performed. On the other hand, if there is no engine start request, such as when the engine is already running, the engine cranking is naturally not started (NO in step S002).

  When the cranking start condition is satisfied when the vehicle speed is equal to or higher than the engine startable speed and the engine is requested to start, the HV-ECU 21 uses the engine temperature (water temperature) and the accelerator opening as parameters, and is necessary when the clutch is engaged. A clutch engagement speed corresponding to the current engine temperature (water temperature) and the accelerator opening is determined with reference to a map or the like that defines torque (step S003). At the same time, the HV-ECU 21 selects an optimum gear from the gears that can be used for cranking start based on the current vehicle speed and the like.

  When the accelerator opening is in a predetermined high opening range (eg, 70% or more), it is regarded as a sudden start and a necessary torque command is given to the MG 12 and the clutch is engaged at a high speed, so that the vehicle speed is started. A map set to reach the possible speed rapidly can be used. Also in this case, the shock can be reduced by increasing the torque value applied to the MG 12 as will be described later.

  The HV-ECU 21 starts clutch engagement control at the determined clutch engagement speed and gear position, and starts transmission of vehicle kinetic energy to the engine (step S004).

  Subsequently, the HV-ECU 21 calculates the engine rotation cycle from the output signal value of the engine crank angle sensor (step S005) and estimates the engine piston top dead center (step S006) in order to estimate the torque fluctuation at the start of the engine. Execute.

  Subsequently, the HV-ECU 21 corrects the torque variation pattern at the start of engine cranking, which is measured in advance so as to synchronize with the estimated engine rotation cycle and engine piston top dead center. The signal value of the reverse phase that cancels the torque applied to is calculated (step S007). During cranking, a load is generated on the engine, so that the signal value in the opposite phase is a positive value, and the engine torque is added after the start of the engine is completed, so the signal value in the opposite phase is a negative value. It becomes the value of.

  Further, since the load at the time of cranking when the engine water temperature is low is large compared to the cranking after the warm-up operation, the HV-ECU 21 corrects the fluctuation range of the signal value of the opposite phase according to the engine water temperature. It is good also as making it perform.

  Subsequently, the HV-ECU 21 calculates a canceling torque value necessary for canceling the torque fluctuation from the signal value having the opposite phase (step S008).

  Finally, the HV-ECU 21 instructs the MG 12 as a motor instruction torque using the sum of the offset torque value and the vehicle traveling torque for traveling the vehicle (step S009).

  FIG. 4 is an example of the behavior of the vehicle when starting from a vehicle stop state in a vehicle to which the present invention is applied. When the accelerator is depressed from the stop state of the accelerator opening 0% and the vehicle speed 0, the MG torque rises and the vehicle transitions to the MG running state. At this time, since the clutch is in a disengaged state, the torque applied to the wheel by the engine (ENG) is zero.

  Thereafter, when the vehicle speed reaches the vehicle startable vehicle speed, the engine start control shown in and after step S003 in FIG. 3 is started, and the speed and clutch engagement speed (gradient) suitable for the vehicle state and the driver's intention to travel are set. Thus, clutch engagement control is executed.

  When the kinetic energy of the vehicle starts to be transmitted to the engine side via the clutch, the engine speed increases and a loss of kinetic energy occurs.

  On the other hand, since the MG 12 outputs a canceling torque that compensates for the loss of kinetic energy, as a result, fluctuations in torque applied to the wheels are suppressed (see the “torque applied to the combined wheels” line in FIG. 4). .

  Thereafter, when the engine start is completed and the engine output torque is transmitted to the wheels, the torque of the MG 12 is abruptly reduced and switching to engine running is performed.

  In the example of FIG. 4, a negative torque value (regenerative control) is given to MG 12 for a certain period immediately before completion of engine start. This is in order to avoid a shock caused by the sum of the engine output torque and the MG output torque overshooting the target.

  As described above, during the eco-run, torque fluctuation when the engine is cranked using kinetic energy is suppressed.

  Although one embodiment of the present invention has been described above, the technical scope of the present invention is not limited to the description of the embodiment described above, and various modifications may be made according to the specifications of the vehicle to be applied. Can be added.

  For example, in the above-described embodiment, it has been described that the cranking of the engine is started when the vehicle speed exceeds the engine startable speed. However, when the engine is stopped, the accelerator opening increases and the accelerator opening increase amount increases. The engine cranking may be started when the value exceeds a certain level.

  Further, in the above-described embodiment, based on the engine rotation cycle calculated from the value of the engine crank angle sensor and the top dead center of the engine piston, the torque variation pattern prepared in advance is corrected to obtain the torque that is brought to the wheel. Although described as an estimation, it is also possible to employ a method of estimating the torque to be applied to the wheel using the clutch engagement speed at the time of cranking and the used gear position as parameters.

1 is a block diagram showing a configuration of a hybrid vehicle to which the present invention can be applied. 1 is a skeleton diagram illustrating a schematic configuration (fourth speed state) of a vehicle drive mechanism according to an embodiment of the present invention. It is a flowchart showing the process performed for every predetermined time in the drive source control measure (HV-ECU) of the vehicle which concerns on one Embodiment of this invention. It is an example of the behavior of the vehicle when the vehicle to which the present invention is applied starts from a vehicle stop state. It is a figure for demonstrating the behavior of the vehicle at the time of starting from a vehicle stop state in the conventional vehicle.

Explanation of symbols

11 Engine (ENG)
12 Motor generator (MG)
13 Transmission 14 Differential (differential)
15, 15 'Axle shaft 16, 16' Drive wheel 17 Clutch actuator 18 Shift actuator 19 Battery 20 Starter 21 HV-ECU (vehicle drive source control device)
22 MG-ECU and inverter 23 EG-ECU
24 AMT-ECU
25 Battery ECU
26 Indicator 31 Output shaft 32 Flywheel 33 Clutch element 34 Transmission input shaft 35-41, 49 Drive gear 42 Transmission output shaft 43-48 Driven gear 50 Rev idler gear shaft 51 Rev idler gear 52-54 Hub member 55-57 Sleeve Member 58 gear 60 MG output shaft 61 driving gear 62 intermediate reduction shaft 63 driven gear 64 second driving gear 65 resolver 66 stator member 67 rotor member 70 ring gear

Claims (4)

A drive source control device for a vehicle that controls a motor that drives the vehicle and an engine that is controlled to stop depending on the running state of the vehicle,
Engine starting means for starting a stopped engine by cranking using kinetic energy of the vehicle;
Torque fluctuation estimating means for estimating the torque caused to the wheels during cranking of the engine;
Torque fluctuation canceling means for adjusting the command torque to the motor so as to cancel the estimated torque,
In the power transmission system that transmits power from the engine to the wheels, the engine, the clutch, and the transmission are arranged in this order from the upstream side to the downstream side of the power transmission system.
The motor can transmit power from the downstream side in the power transmission system to the engine via the transmission and the clutch.
When the accelerator opening is equal to or greater than a predetermined value, the engine starter starts cranking start of the engine regardless of the vehicle speed;
The torque fluctuation estimating means estimates both torque loss due to cranking of the engine and torque generated after engine startup;
A vehicle drive source control device. The engine starting means, when the accelerator opening is greater than or equal to a predetermined value, to increase the clutch engagement speed at the time of cranking the engine than when the accelerator opening is less than a predetermined value,
The vehicle drive source control device according to claim 1. The torque fluctuation estimating means estimates a torque to be provided to the wheel by a torque fluctuation pattern based on an engine rotation period determined from an engine crank angle sensor value and a top dead center of the engine piston;
The drive source control device for a vehicle according to claim 1 or 2. The torque fluctuation canceling means is configured to change the amount of instruction torque to the motor based on engine water temperature;
The vehicle drive source control device according to any one of claims 1 to 3.

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