JP2017218069A - Hybrid vehicle and control method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hybrid vehicle and control therefor, which enable filter reproduction time to be shortened while limiting a sense of a hybrid vehicle jumping given to the driver when starting the vehicle.SOLUTION: In a hybrid vehicle, even in the case of a hybrid vehicle becoming a travel stop state during execution of filter-reproducing idling-increase control and a motor clutch 15 becoming disengaged, a control apparatus 70 continues the filter-reproducing idling-increase control instead of stopping it. In the case of the hybrid vehicle start travelling in the state of the filter-reproducing idling-increase control being executed, with the motor clutch disengaged, the control apparatus executes control for decreasing an engaging speed of the motor clutch than in the case of the motor clutch becoming disengage when no filter-reproducing idling-increase control is executed.SELECTED DRAWING: Figure 1

Description

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

  Conventionally, a hybrid vehicle (hereinafter referred to as “HEV”) having an engine and a motor generator is known. As such an HEV, for example, Patent Document 1 discloses an HEV having a structure in which a clutch is disposed between an engine and a motor generator, and an exhaust passage having a filter for exhaust purification. Patent Document 1 also discloses a technique for executing idle regeneration control during filter regeneration that increases the engine speed during regeneration of the filter.

Japanese Patent No. 5145542

  By the way, HEV having a structure in which a motor generator is disposed between the engine and the transmission and a clutch is disposed between the motor generator and the transmission may be employed as the HEV. In such an HEV, for example, when the clutch is disengaged in the HEV running stop state, the filter regeneration idle-up control is executed, and when the HEV starts thereafter, the clutch is brought into the contact state at the normal connection speed. If this happens, the engine torque increased by the execution of the idle-up control during filter regeneration is suddenly transmitted to the transmission, which may give the driver a feeling of jumping out.

  Therefore, conventionally, in order to suppress the feeling of popping out, when the HEV having the above structure is in a travel stop state and the clutch is in a disengaged state, the execution of the idle-up control during filter regeneration has been stopped. . For this reason, it cannot be said that the filter regeneration time is sufficiently shortened.

  The present invention has been made in view of the above, and an object of the present invention is to provide a hybrid vehicle capable of reducing the regeneration time of the filter while suppressing giving a feeling of jumping to the driver when the hybrid vehicle starts, and control thereof. It is to provide a method.

In order to achieve the above object, a hybrid vehicle according to the present invention includes a structure in which a motor generator is disposed between an engine and a transmission and a clutch is disposed between the motor generator and the transmission, and an exhaust of the engine. A filter for purifying exhaust gas disposed in the passage, and a control device that executes idle-up control during filter regeneration that increases the engine speed above a predetermined speed when the filter is regenerated, the control device comprising: Even when the hybrid vehicle is in a travel stop state and the clutch is disengaged during execution of the filter regeneration idle-up control, the filter regeneration idle-up control is continued without stopping. The clutch is disengaged and the filter When the hybrid vehicle starts in a state where the regeneration idle-up control is executed, the clutch connection speed is set higher than that in the case where the clutch is engaged when the filter regeneration idle-up control is not executed. It is characterized by executing control to reduce.

  In order to achieve the above object, a hybrid vehicle control method according to the present invention includes a structure in which a motor generator is disposed between an engine and a transmission, and a clutch is disposed between the motor generator and the transmission. An exhaust purification filter disposed in an exhaust passage of the engine, the method of controlling a hybrid vehicle, wherein when the filter is regenerated, the engine regeneration speed is increased above a predetermined speed And when the hybrid vehicle is stopped during the regeneration of the filter and the clutch is disengaged during the idle regeneration of the filter. Continue to run without stopping control When the hybrid vehicle starts in a state where the clutch is disengaged and the filter regeneration idle-up control is executed, the clutch connection speed is set when the filter regeneration idle-up control is not executed. Control is performed that lowers the clutch compared to when the clutch is engaged.

  According to the present invention, even when the hybrid vehicle is in a travel stop state and the clutch (the clutch between the motor generator and the transmission) is in a disengaged state during execution of the idle regeneration control during filter regeneration, the filter Since the idle-up control during reproduction is continuously executed without being stopped, the reproduction time of the filter can be shortened. According to the present invention, when the hybrid vehicle starts with the clutch disengaged and the filter regeneration idle-up control executed, the clutch connection speed is set to the idle regeneration during filter regeneration. Since the control is performed to be lower than when the clutch is in the engaged state when the control is not executed, the engine torque that has become high due to the idle-up control during filter regeneration can be transmitted to the transmission slowly. it can. Thereby, it can suppress giving a feeling of jumping out to a driver.

  As described above, according to the present invention, it is possible to reduce the regeneration time of the filter while suppressing giving a feeling of popping out to the driver when the hybrid vehicle starts.

It is a figure showing an example of composition of a hybrid vehicle concerning an embodiment. It is an example of the flowchart of the motor clutch connection speed fall control and increase torque absorption control which concern on embodiment.

  Hereinafter, a hybrid vehicle and a control method thereof according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a diagram illustrating an example of a configuration of a hybrid vehicle (hereinafter referred to as “HEV”) according to the present embodiment. The HEV has a structure in which a motor generator 21 is disposed between the engine 10 and the transmission 30 and a motor clutch 15 is disposed between the motor generator 21 and the transmission 30, and is disposed in the exhaust passage 41 of the engine 10. The exhaust purifying filter 42 and the control device 70 are provided at least. As an example of this, the HEV according to the present embodiment has the configuration illustrated in FIG.

Specifically, as illustrated in FIG. 1, the engine 10 includes an engine body 11 having a plurality of cylinders 12 (four illustrated in FIG. 1). In the engine 10, the crankshaft 13 is rotationally driven by thermal energy generated by the combustion of fuel in the cylinder 12. In addition, the specific kind of the engine 10 is not specifically limited, For example, a diesel engine, a gasoline engine, etc. can be used. In this embodiment, a diesel engine is used as an example of the engine 10.

  Between the HEV engine 10 and the motor generator 21, a torque converter 17 and an engine clutch 14 are arranged in this order. Specifically, the power input shaft 18 a of the torque converter 17 is connected to one end of the crankshaft 13 of the engine 10, and the power output shaft 18 b of the torque converter 17 is connected to the rotating shaft 22 of the motor generator 21 via the engine clutch 14. It is connected to one end. For example, a wet multi-plate clutch can be used as the engine clutch 14. The operation of the engine clutch 14 is controlled by the control device 70.

  The HEV hybrid system 20 includes the above-described motor generator 21, and an inverter 23, a high voltage battery 24, a DC / DC converter 25, and a low voltage battery 26 that are electrically connected to the motor generator 21 in order. . The specific type of the motor generator 21 is not particularly limited, but in the present embodiment, a permanent magnet type AC synchronous motor capable of generating operation is used as an example. The other end of the rotating shaft 22 of the motor generator 21 is connected to the input shaft 31 of the transmission 30 via the motor clutch 15. For example, a wet multi-plate clutch can be used as the motor clutch 15. The operation of the motor clutch 15 is controlled by the control device 70.

  Preferred examples of the high voltage battery 24 include a lithium ion battery and a nickel metal hydride battery. As the low voltage battery 26, a lead battery is used. The DC / DC converter 25 has a function of controlling the charge / discharge direction and the output voltage between the high voltage battery 24 and the low voltage battery 26. The low voltage battery 26 supplies power to various vehicle electrical components 27. Various parameters (for example, current value, voltage value, SOC, etc.) in the hybrid system 20 are detected by the BMS 28 (battery management system).

  The transmission 30 is an AMT or AT that automatically shifts to a target gear determined based on the HEV operating state and preset map data. The rotational torque changed by the transmission 30 is transmitted to the differential 34 through the propeller shaft 33 connected to the output shaft 32 of the transmission 30, and is distributed as a driving force to the pair of driving wheels 35 as rear wheels.

  The specific type of the exhaust purification filter 42 (hereinafter abbreviated as the filter 42) is not particularly limited as long as it can collect and remove PM in the exhaust. In the embodiment, a diesel particulate filter is used as an example. An exhaust gas purification catalyst (not shown) is also arranged upstream of the filter 42 in the exhaust passage 41.

  Next, the HEV control device 70 will be described. In the present embodiment, an electronic control device is used as the control device 70. This electronic control device includes a CPU having a function as a control unit for executing various control processes, and a ROM, a RAM, etc. having a function as a storage unit for storing various data and programs used for the operation of the CPU. A microcomputer is provided. The control device 70 is connected to the motor generator 21 and the like through a signal line (indicated by a one-dot chain line).

The controller 70 causes the motor generator 21 supplied with power from the high voltage battery 24 to assist at least a part of the driving force of the HEV during acceleration of the HEV or the like. Further, the control device 70 causes the motor generator 21 to perform regenerative power generation during HEV inertia running or braking, and converts surplus kinetic energy generated in the propeller shaft 33 or the like into electric power to generate a high-voltage battery. 24 is charged. Further, when the control device 70 drives the motor generator 21 with the engine clutch 14 disengaged and the motor clutch 15 engaged, for example, the HEV can run the motor alone.

  Here, when a large amount of PM in the exhaust accumulates on the filter 42, the performance of the filter 42 is degraded. Therefore, when the predetermined condition for which regeneration of the filter 42 is desired (that is, the predetermined condition for which PM deposited on the filter 42 is desired to be combusted) is satisfied, the control device 70, for example, upstream of the filter 42. By supplying fuel to the exhaust passage 41, the exhaust temperature is raised to the combustion temperature of PM by the reaction heat of the fuel, and a process for removing the PM deposited on the filter 42 by combustion (referred to as “filter regeneration process”). Run.

  The specific content of the predetermined condition is not particularly limited. For example, the condition that the amount of PM deposited on the filter 42 is equal to or greater than a preset reference value, or the HEV travel distance is predetermined. Various conditions such as a condition that the distance is equal to or greater than the set reference distance can be used. In the present embodiment, as an example of the predetermined condition, a condition that the amount of PM deposited on the filter 42 is equal to or more than a preset reference value is used. The HEV includes a fuel addition valve (not shown) in the exhaust passage 41 upstream of the filter 42 and downstream of the exhaust manifold. The control device 70 according to the present embodiment is configured to regenerate the filter. As an example of processing, fuel is supplied from the fuel addition valve into the exhaust passage 41.

  Further, the control device 70 further executes filter regeneration idle-up control for increasing the idle speed of the engine 10 to be higher than a predetermined speed when the filter regeneration process is executed (that is, during filter regeneration). The specific value of the predetermined rotational speed is not particularly limited. For example, the idle rotational speed of the engine 10 when the idle regeneration control during filter regeneration is not executed (that is, the idle rotational speed at the normal time) is set. Can be used.

  That is, in this case, when the engine 10 is idling at the normal idle speed during the filter regeneration, the engine regeneration speed is set to the normal speed by executing the filter regeneration idle-up control. It rises higher than the idle speed.

  By executing this filter regeneration idle-up control, the exhaust gas temperature increases compared to the case where such control is not performed, so that the filter regeneration time can be shortened.

  Further, the control device 70 does not stop the idle-up control at the time of filter regeneration even when the HEV is stopped during the execution of the idle-up control at the time of filter regeneration and the motor clutch 15 is disengaged. Continue to run.

  When the HEV starts in a state where the motor clutch 15 is disengaged and the filter regeneration idle-up control is executed, the control device 70 sets the connection speed of the motor clutch 15 to the idle regeneration during filter regeneration. A control is performed to make the motor clutch 15 lower than when the motor clutch 15 is in the engaged state when the control is not executed (hereinafter, this control is referred to as “motor clutch connection speed lowering control”).

In addition, the control device 70 according to the present embodiment, when the HEV starts while the motor clutch 15 is in the disengaged state and the filter regeneration idle-up control is executed, performs the motor clutch connection speed reduction control. In addition, a control for causing the motor generator 21 to absorb the torque increase of the engine 10 due to the execution of the filter regeneration idle-up control (hereinafter, this control is referred to as “increased torque absorption control”) is also executed.

  Next, details of the above-described motor clutch connection speed reduction control and increase torque absorption control will be described using a flowchart. FIG. 2 is an example of a flowchart of motor clutch connection speed reduction control and increase torque absorption control according to the present embodiment. The control device 70 repeatedly executes the flowchart of FIG. 2 at a predetermined cycle from the start of the HEV. The hybrid vehicle control method according to the present embodiment is realized by the control process of the control device 70. Moreover, each step of FIG. 2 is specifically performed by the control unit (CPU) of the control device 70.

  In step S10, the control device 70 determines whether the HEV is in a travel stop state and the motor clutch 15 is in a disengaged state. In the present embodiment, the HEV travel stop state includes the case where the transmission 30 is in the D range and the HEV is in the travel stop state (the vehicle speed is zero). Further, since the control device 70 according to the present embodiment puts the motor clutch 15 in the disengaged state when the HEV enters the travel stop state, when the HEV enters the travel stop state, the step S10 is normally performed. It is determined as YES.

  Note that when the HEV enters the travel stop state, the control device 70 may leave the engine clutch 14 in the engaged state or may be in the disconnected state.

  However, when the filter regeneration idle-up control is executed when the HEV is in a travel stop state, the engine clutch 14 is preferably in a disconnected state until a HEV start request is made. According to this configuration, when the engine 10 is rotated during execution of the filter regeneration idle-up control, it is not necessary to rotate the motor generator 21 together, so that the rotational resistance of the engine 10 can be reduced. Thereby, fuel consumption can be saved. Therefore, as an example, the control device 70 according to the present embodiment keeps the engine clutch 14 in a disengaged state until there is a HEV start request (until YES is determined in step S30 described later). And

  When it is determined NO in step S10 of FIG. 2, the control device 70 executes the flowchart from the start (return). When it determines with YES by step S10, the control apparatus 70 determines whether it is the state in which the idle-up control at the time of filter regeneration was performed (step S20). When it determines with NO by step S20, the control apparatus 70 performs a flowchart from a start (return).

  When it determines with YES by step S20, the control apparatus 70 determines the presence or absence of the HEV start request | requirement (request | requirement of starting HEV) (step S30). Although the specific content of step S30 is not particularly limited, as an example, the control device 70 according to the present embodiment has a brake pedal depression amount of zero by the driver and an accelerator pedal depression amount of zero. If the value becomes too large, it is determined that there is a HEV start request.

  If YES is determined in step S30, this corresponds to a case where the HEV starts in a state in which the motor clutch 15 is disengaged in the HEV running stop state and the filter regeneration idle-up control is executed. .

When it determines with NO by step S30, the control apparatus 70 returns to the start of a flowchart (return). When it determines with YES by step S30, the control apparatus 70 controls the engine clutch 14 to a contact state (step S40). As a result, the torque of the engine 10 is changed to the torque converter 17, the engine clutch 14, and the motor generator 21.
To the motor clutch 15 (specifically, the disconnected motor clutch 15).

  Next, the control device 70 starts execution of motor clutch connection speed reduction control and increase torque absorption control (step S50). Note that the motor clutch connection speed reduction control and the increase torque absorption control may be performed simultaneously, the execution of the increase torque absorption control may be started after the execution of the motor clutch connection speed reduction control, or the execution of the increase torque absorption control. You may start execution of motor clutch connection speed fall control after the start.

  In the motor clutch connection speed reduction control according to step S50, specifically, the control device 70 sets the connection speed of the motor clutch 15 (stroke speed at the time of connection) to the motor clutch 15 when the filter regeneration idle-up control is not executed. Is lower than the connection speed (that is, the normal connection speed) in the case of the contact state. That is, the control device 70 slowly changes the disconnected motor clutch 15 to the engaged state.

  In addition, the connection speed of the motor clutch 15 that is slower than the connection speed of the motor clutch 15 at the normal time is stored in advance in the storage unit (for example, ROM) of the control device 70. The controller 70 causes the connection speed of the motor clutch 15 to be lower than the normal connection speed by connecting the motor clutch 15 at the connection speed stored in the storage unit (slower connection speed than normal). ing.

  Note that if the acceleration at the time of HEV start exceeds the acceleration at the time of engine creep, the driver tends to feel a sense of popping out. Therefore, it is preferable to set the connection speed of the motor clutch 15 in advance so that the acceleration of the HEV when the motor clutch 15 is connected is within the acceleration during engine creep.

  Further, in the increase torque absorption control according to step S50, specifically, the control device 70 causes the motor generator 21 to absorb an increase in the torque (output torque) of the engine 10 due to the execution of the filter regeneration idle-up control. The details of this control are as follows.

  First, the control apparatus 70 acquires the rotation speed (engine rotation speed) of the engine 10 by acquiring the detection result of an engine rotation speed sensor (not shown). An arithmetic expression or a map for calculating the torque of the engine 10 (engine torque) from the engine speed is stored in advance in the storage unit (for example, ROM) of the control device 70. Then, in the increased torque absorption control according to step S50, the control device 70 acquires the amount of increase in the engine speed due to the execution of the filter regeneration idle-up control based on the detection result of the engine speed sensor. Further, an increase amount of the engine torque corresponding to the increase amount of the engine speed is calculated based on the arithmetic expression or the map.

  Then, the control device 70 causes the motor generator 21 to absorb the increase amount of the engine torque calculated in this way. Specifically, the control device 70 causes the motor generator 21 to regenerate power by the amount of increase in engine torque calculated as described above, and cause the motor generator 21 to absorb the increase in engine torque. As described above, the control device 70 according to the present embodiment executes the increased torque absorption control.

  After completing the motor clutch connection speed reduction control and the increase torque absorption control according to step S50, the control device 70 returns to the start of the flowchart (return).

  According to the present embodiment described above, even when the HEV is stopped during running and the motor clutch 15 is disengaged during execution of the filter regeneration idle up control, the filter regeneration idle up control is performed. Since it is continuously executed without stopping, the reproduction time of the filter 42 can be shortened. Further, according to the present embodiment, when the HEV starts while the motor clutch 15 is disengaged and the filter regeneration idle-up control is executed, the motor clutch connection speed reduction control control (step S50). Therefore, the torque of the engine 10 that has become high rotation due to the execution of the idle-up control during filter regeneration can be transmitted to the transmission 30 slowly. Thereby, it can suppress giving a feeling of jumping out to a driver.

  That is, according to the present embodiment, it is possible to shorten the regeneration time of the filter 42 while suppressing giving a feeling of popping out to the driver when HEV starts.

  Further, according to the present embodiment, when the HEV starts while the motor clutch 15 is in the disengaged state and the filter regeneration idle-up control is executed, the increased torque absorption control (step S50) is also executed. Therefore, the motor generator 21 absorbs the increase in engine torque due to the execution of the idle regeneration control during filter regeneration, so that the increase in engine torque can be effectively suppressed from being transmitted to the transmission 30. Thereby, giving a feeling of jumping out to a driver can be controlled more effectively.

  Although the preferred embodiments of the present invention have been described above, the present invention is not limited to such specific embodiments, and various modifications and changes can be made within the scope of the gist of the present invention described in the claims. Is possible.

10 Engine 15 Motor clutch (clutch)
17 Torque converter 21 Motor generator 30 Transmission 41 Exhaust passage 42 Exhaust purification filter 70 Control device

Claims (3)

A structure in which a motor generator is disposed between the engine and the transmission and a clutch is disposed between the motor generator and the transmission; an exhaust purification filter disposed in the exhaust passage of the engine; and A control device for performing idle regeneration control during filter regeneration for increasing the engine speed during regeneration to a value higher than a predetermined engine speed,
The controller is
Even when the hybrid vehicle is stopped during the filter regeneration idle-up control and the clutch is disengaged, the filter regeneration idle-up control is continuously executed without stopping. And
When the hybrid vehicle starts in a state where the clutch is disengaged and the filter regeneration idle-up control is executed, the clutch connection speed is set when the filter regeneration idle-up control is not executed. A hybrid vehicle that executes control that lowers the clutch as compared to when the clutch is engaged.   When the hybrid vehicle starts in a state where the clutch is disengaged and the filter regeneration idle-up control is executed, the control device performs the engine regeneration by executing the filter regeneration idle-up control. The hybrid vehicle according to claim 1, further executing control for causing the motor generator to absorb an increase in torque. A hybrid comprising a structure in which a motor generator is disposed between an engine and a transmission, and a clutch is disposed between the motor generator and the transmission, and an exhaust purification filter disposed in an exhaust passage of the engine A vehicle control method comprising:
During the regeneration of the filter, the filter regeneration idle-up control is performed to increase the engine speed above a predetermined number of revolutions, and the hybrid vehicle is brought into a stopped state during the execution of the filter regeneration idle-up control. Even when the clutch is in a disengaged state, the idle regeneration control during the filter regeneration is continuously executed without being stopped,
When the hybrid vehicle starts in a state where the clutch is disengaged and the filter regeneration idle-up control is executed, the clutch connection speed is set when the filter regeneration idle-up control is not executed. A control method for a hybrid vehicle, wherein control is performed to make the control lower than when the clutch is engaged.

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