JP4135671B2 - Hybrid vehicle mode transition control device - Google Patents

Description

  The present invention relates to a mode transition control device for a hybrid vehicle having, as travel modes, a continuously variable transmission ratio mode that starts with a continuously variable transmission ratio and a low-side fixed transmission ratio mode that starts with a low-side fixed transmission ratio.

Conventionally, a four-element two-degree-of-freedom planetary gear mechanism in which four input / output elements are arranged on a collinear diagram is configured, and one of the two elements arranged inside the input / output elements is connected to There is known a hybrid drive device in which an input is assigned to an output to the drive system on the other side, and a first motor generator and a second motor generator are connected to two elements arranged on both outer sides of the inner element, respectively. In this hybrid drive device, as the travel mode, the “continuously variable transmission mode” that travels using the engine and the two motor generators, the low brake is engaged, the engine and the two motor generators, or the two motors. And a “low gear fixed mode” that travels using only the generator (see, for example, Patent Document 1).
JP 2003-32808 A

  However, in the above-described conventional hybrid vehicle, when the vehicle is started with priority on the “continuously variable transmission mode” in order to start smoothly, the towing vehicle starts when starting uphill or pulling a faulty vehicle. In some cases, there is a problem that the driving force is insufficient, the vehicle moves backward (rollback) at the time of start, and the startability is deteriorated.

  The present invention has been made paying attention to the above-mentioned problem, and at the time of starting with the continuously variable transmission ratio mode selected, ensuring smooth starting performance at low load starting and avoiding rollback at high load starting It is an object of the present invention to provide a mode transition control device for a hybrid vehicle that can ensure both startability and safety.

In order to achieve the above object, the present invention has a differential device in which four or more input / output elements are arranged on a collinear diagram, and two elements arranged inside the input / output elements. The input from the engine is assigned to one side, and the output member to the drive system is assigned to the other side, and the first motor generator and the second motor generator are connected to the two elements arranged on both outer sides of the inner elements, respectively. In a hybrid vehicle equipped with a driving force synthesis transmission,
As the running mode, it has a continuously variable transmission ratio mode that starts with a continuously variable transmission ratio, and a low fixed gear ratio mode that starts with a fixed fixed gear ratio on the low side,
High load start detection means for detecting vehicle start in a high load state is provided,
An engine clutch is provided between the engine and the engine input element of the differential;
One element of the differential is fixed to the case, and a low-side fixed gear ratio brake for obtaining a low-side fixed gear ratio is provided,
When starting with the continuously variable transmission ratio mode selected, if the high load start detecting means detects that the start is in a high load state, the engine clutch is released, and the first motor generator and the second motor generator are released. The rotation speed control of the collinear chart is controlled to the slope of the low-side fixed gear ratio mode, and the motor generator is driven from the continuously variable gear ratio mode by the sequence control for engaging the low-side fixed gear ratio brake. High load start corresponding mode transition control means for mode transition to the low-side fixed gear ratio mode is provided.

  Therefore, in the mode transition control device for a hybrid vehicle according to the present invention, the high-load start corresponding mode transition control means allows the high-load start detection means to When it is detected that the vehicle has started, control for mode transition from the continuously variable gear ratio mode to the low-side fixed gear ratio mode is performed. In other words, the continuously variable transmission ratio mode is maintained when starting with a low load, and the mode transition is made to the low-side fixed transmission ratio mode with a large driving force automatically output when starting with a high load. As a result, when starting with the continuously variable transmission ratio mode selected, both smooth start performance at low load start and startability by avoiding rollback at high load start must be achieved. Can do.

  Hereinafter, the best mode for realizing a mode transition control device for a hybrid vehicle of the present invention will be described based on Example 1 shown in the drawings.

First, the drive system configuration of the hybrid vehicle will be described.
FIG. 1 is an overall system diagram showing a drive system of a hybrid vehicle to which the mode transition control device of Embodiment 1 is applied. As shown in FIG. 1, the drive system of the hybrid vehicle in the first embodiment includes an engine E, a first motor generator MG1, a second motor generator MG2, an output shaft OUT (output member), and a driving force synthesis transmission. TM. The driving force combined transmission TM includes a first planetary gear PG1 (first differential), a second planetary gear PG2 (second differential), and a third planetary gear PG3 (third differential). The engine clutch EC, the low brake LB (first friction engagement element), the high clutch HC (second friction engagement element), and the high / low brake HLB (third friction engagement element).

  The engine E is a gasoline engine or a diesel engine, and the opening degree of a throttle valve and the like are controlled based on a control command from an engine controller 1 described later.

  The first motor generator MG1 and the second motor generator MG2 are synchronous motor generators having a rotor in which permanent magnets are embedded and a stator around which a stator coil is wound. Based on this, the three-phase alternating current generated by the inverter 3 is independently controlled by applying it to each stator coil.

  The first planetary gear PG1, the second planetary gear PG2, and the third planetary gear PG3 of the driving force combining transmission TM are all single-pinion type planetary gears with two degrees of freedom. The first planetary gear PG1 includes a first sun gear S1, a first pinion carrier PC1 that supports the first pinion P1, and a first ring gear R1 that meshes with the first pinion P1. The second planetary gear PG2 includes a second sun gear S2, a second pinion carrier PC2 that supports the second pinion P2, and a second ring gear R2 that meshes with the second pinion P2. The third planetary gear PG3 includes a third sun gear S3, a third pinion carrier PC3 that supports the third pinion P3, and a third ring gear R3 that meshes with the third pinion P3.

  The first sun gear S1 and the second sun gear S2 are directly connected by a first rotating member M1, the first ring gear R1 and the third sun gear S3 are directly connected by a second rotating member M2, and the second pinion carrier PC2 The third ring gear R3 is directly connected by a third rotating member M3. Accordingly, the three planetary gears PG1, PG2, and PG3 include the first rotating member M1, the second rotating member M2, the third rotating member M3, the first pinion carrier PC1, the second ring gear R2, and the third pinion carrier PC3. It has 6 rotating elements.

The connection relationship between the power sources E, MG1, MG2, the output shaft OUT, and the engagement elements EC, LB, HC, HLB for the six rotating elements of the differential device will be described.
A second motor generator MG2 is connected to the first rotating member M1 (S1, S2).
The second rotating member M2 (R1, R3) is not connected to any input / output element.
An engine E is connected to the third rotating member M3 (PC2, R3) via an engine clutch EC.
A second motor generator MG2 is connected to the first pinion carrier PC1 via a high clutch HC. Further, it is connected to the transmission case TC via a low brake LB.
A first motor generator MG1 is connected to the second ring gear R2. Further, it is connected to the transmission case TC via a high / low brake HLB.
An output shaft OUT is connected to the third pinion carrier PC3. A driving force is transmitted from the output shaft OUT to the left and right driving wheels via a propeller shaft, a differential, and a drive shaft (not shown).

  Due to the above connection relationship, the first motor generator MG1 (R2), the engine E (PC2, R3), the output shaft OUT (PC3), and the second motor generator MG2 (S1, S2) on the alignment chart shown in FIG. A rigid lever model that is arranged in order and can easily express the dynamic operation of the planetary gear train (the first planetary gear PG1 lever (1), the second planetary gear PG2 lever (2), the third planetary gear PG3 lever) (3)) can be introduced. Here, the “collinear diagram” is a velocity diagram used in a simple and easy-to-understand method of drawing instead of the method of obtaining by equation when considering the gear ratio of the differential gear, Take the number of rotations (rotation speed) of the rotating elements, take each rotating element such as ring gear, carrier, sun gear, etc. on the horizontal axis, and set the interval between each rotating element to the collinear lever ratio (α , Β, δ).

  The engine clutch EC is a multi-plate friction clutch that is engaged by hydraulic pressure, and is disposed at a position that coincides with the rotational speed axis of the engine E on the alignment chart of FIG. Is input to the third rotation member M3 (PC2, R3) which is an engine input rotation element.

  The low brake LB is a multi-plate friction brake fastened by hydraulic pressure, and is disposed on the outer side of the rotational speed axis of the second motor generator MG2 on the alignment chart of FIG. The "low gear fixed mode" and the "low-side continuously variable transmission mode" that share the low-side gear ratio by the engagement are realized.

  The high clutch HC is a multi-plate friction clutch that is engaged by hydraulic pressure, and is disposed at a position that coincides with the rotational speed axis of the second motor generator MG2 on the alignment chart of FIG. "2-speed fixed mode", "high-side continuously variable transmission mode" and "high gear fixed mode" are realized.

  The high / low brake HLB is a multi-plate friction brake fastened by hydraulic pressure, and is arranged at a position coincident with the rotational speed axis of the first motor generator MG1 on the alignment chart of FIG. 2 and fastened together with the low brake LB. Thus, the gear ratio is set to the “low gear fixed mode” on the underdrive side, and the gear ratio is set to the “high gear fixed mode” on the overdrive side by engaging with the high clutch HC.

Next, the control system of the hybrid vehicle will be described.
As shown in FIG. 1, the hybrid vehicle control system in the first embodiment includes an engine controller 1, a motor controller 2, an inverter 3, a battery 4, a hydraulic control device 5, an integrated controller 6, and an accelerator opening. A sensor 7, a vehicle speed sensor 8, an engine speed sensor 9, a first motor generator speed sensor 10, a second motor generator speed sensor 11, and a third ring gear speed sensor 12 are configured. Has been.

  The engine controller 1 responds to an engine operating point (Ne) according to a target engine torque command or the like from an integrated controller 6 that inputs an accelerator opening AP from an accelerator opening sensor 7 and an engine speed Ne from an engine speed sensor 9. , Te), for example, is output to a throttle valve actuator (not shown).

  The motor controller 2 responds to a target motor generator torque command from the integrated controller 6 that inputs motor generator rotation speeds N1 and N2 from both motor generator rotation speed sensors 10 and 11 by a resolver, and the motor of the first motor generator MG1. A command for independently controlling the operating point (N1, T1) and the motor operating point (N2, T2) of the second motor generator MG2 is output to the inverter 3. The motor controller 2 outputs information on the battery S.O.C representing the state of charge of the battery 4 to the integrated controller 6.

  The inverter 3 is connected to the respective stator coils of the first motor generator MG1 and the second motor generator MG2, and generates an independent three-phase alternating current according to a command from the motor controller 2. The inverter 3 is connected to a battery 4 that is discharged during power running and charged during regeneration.

  The hydraulic control device 5 receives a hydraulic command from the integrated controller 6 and performs engagement hydraulic pressure control and release hydraulic pressure control of the engine clutch EC, the low brake LB, the high clutch HC, and the high / low brake HLB. The engagement hydraulic pressure control and the release hydraulic pressure control include a half-clutch control based on a slip engagement control and a slip release control.

  The integrated controller 6 includes an accelerator opening AP from the accelerator opening sensor 7, a vehicle speed VSP from the vehicle speed sensor 8, an engine speed Ne from the engine speed sensor 9, and a first motor generator speed sensor 10. Information such as the first motor generator rotational speed N1, the second motor generator rotational speed N2 from the second motor generator rotational speed sensor 11, the engine input rotational speed ωin from the third ring gear rotational speed sensor 12, and the like. Predetermined arithmetic processing is performed. Then, a control command is output to the engine controller 1, the motor controller 2, and the hydraulic control device 5 according to the calculation processing result.

  The integrated controller 6 and the engine controller 1 and the integrated controller 6 and the motor controller 2 are connected by bidirectional communication lines 14 and 15 for information exchange, respectively.

  Next, the travel mode of the hybrid vehicle will be described.

  The driving mode includes a low gear fixed mode (hereinafter referred to as “Low mode”), a low-side continuously variable transmission mode (hereinafter referred to as “Low-iVT mode”), and a two-speed fixed mode (hereinafter referred to as “2nd mode”). ), A high-side continuously variable transmission mode (hereinafter referred to as “High-iVT mode”), and a high gear fixed mode (hereinafter referred to as “High mode”).

  Regarding the five driving modes, an electric vehicle mode (hereinafter referred to as “EV mode”) in which only the motor generators MG1 and MG2 are driven without using the engine E, and an engine E and both motor generators MG1 and MG2 are used. And a hybrid vehicle mode (hereinafter referred to as “HEV mode”).

  Therefore, as shown in FIG. 2 (five driving modes related to EV mode) and FIG. 3 (five driving modes related to HEV mode), the combination of “EV mode” and “HEV mode” is “10 driving modes”. Will be realized. Here, Fig. 2 (a) is an alignment chart of "EV-Low mode", Fig. 2 (b) is an alignment chart of "EV-Low-iVT mode", and Fig. 2 (c) is "EV-2nd mode". 2D is an alignment chart of “EV-High-iVT mode”, and FIG. 2E is an alignment chart of “EV-High mode”. Fig. 3 (a) is a nomogram for "HEV-Low mode", Fig. 3 (b) is a nomogram for "HEV-Low-iVT mode", and Fig. 3 (c) is "HEV-2nd mode". FIG. 3D is a collinear diagram of “HEV-High-iVT mode”, and FIG. 3E is a collinear diagram of “HEV-High mode”.

The “Low mode” is obtained by engaging the low brake LB, releasing the high clutch HC, and engaging the high / low brake HLB, as shown in the collinear diagram of FIG. 2 (a) and FIG. 3 (a). Low gear fixed mode.
In the “Low-iVT mode”, the low brake LB is engaged, the high clutch HC is released, and the high / low brake HLB is released, as shown in the collinear diagram of FIG. 2 (b) and FIG. 3 (b). This is the low-side continuously variable transmission mode obtained in
The “2nd mode” is obtained by engaging the low brake LB, engaging the high clutch HC, and releasing the high / low brake HLB, as shown in the collinear diagrams of FIG. 2 (c) and FIG. 3 (c). 2 speed fixed mode.
In the “High-iVT mode”, the low brake LB is released, the high clutch HC is engaged, and the high / low brake HLB is released, as shown in the collinear charts of FIGS. 2 (d) and 3 (d). Is a high-side continuously variable transmission mode obtained in
The “High mode” is obtained by releasing the low brake LB, engaging the high clutch HC, and engaging the high / low brake HLB, as shown in the nomographs of FIGS. 2 (e) and 3 (e). High gear fixed mode.

  Then, the mode transition control of the “10 travel modes” is performed by the integrated controller 6. That is, the integrated controller 6 is provided with the “10 travel modes” as shown in FIG. 4, for example, in a three-dimensional space by the required driving force Fdrv (determined by the accelerator opening AP), the vehicle speed VSP, and the battery SOC. The allocated travel mode map is set in advance. When the vehicle travels, the travel mode map is searched based on the detected values of the required driving force Fdrv, the vehicle speed VSP, and the battery SOC, and is determined by the required driving force Fdrv and the vehicle speed VSP. The optimum travel mode is selected according to the vehicle operating point and the battery charge amount. FIG. 4 is an example of a travel mode map that is represented in two dimensions by the required driving force Fdrv and the vehicle speed VSP by cutting out the three-dimensional travel mode map at a value with a sufficient capacity range of the battery S.O.C.

  When the mode transition is performed between the “EV mode” and the “HEV mode” by selecting the travel mode map, as shown in FIG. 5, the engine E is started and stopped, and the engine clutch EC is engaged. Control to release is executed.

  Further, when mode transition between the five modes of the “EV mode” and mode transition between the five modes of the “HEV mode” are performed, they are performed according to the ON / OFF operation table shown in FIG. Also, among the controls that change the running mode, for example, when starting / stopping the engine E and engaging / disengaging clutches and brakes are necessary at the same time, when engaging / disengaging multiple clutches and brakes are necessary, In the case where the motor generator rotation speed control is necessary prior to the start / stop of E or the engagement / release of the clutch or brake, the sequence control is performed according to a predetermined procedure.

  Next, the operation will be described.

[Mode transition control processing for high load start]
FIG. 6 is a flowchart showing the flow of the high load start corresponding mode transition control process executed in the integrated controller 6 of the first embodiment. Each step will be described below (high load start corresponding mode transition control means).

  In step S1, it is determined whether or not the vehicle is starting in "HEV-Low-iVT mode" by confirming low brake LB engagement, high clutch HC release, and high / low brake HLB release. If YES, move to step S2. If NO, the determination to step S1 is repeated.

In step S2, based on the determination that the vehicle is starting in “HEV-Low-iVT mode” in step S1, the driving force is insufficient due to starting uphill road, towing towing a faulty vehicle, etc., and the output rotational speed is negative. If YES, the process proceeds to step S3, and if NO, the process proceeds to return (high load start detection means).
Here, the negative detection of the output rotational speed means that the wheel speed detection value from the wheel speed sensor becomes negative, or the vehicle speed detection value VSP from the vehicle speed sensor 8 that detects the carrier rotation speed of the third planetary gear PG3 is It is detected by becoming negative.

  In step S3, based on the detection that the vehicle is in the reverse state (= rollback) in step S2, the “HEV-Low-iVT mode” is changed to the “HEV-Low mode” via the “EV-Low mode”. In order to change the mode, first, the engine clutch EC is released, and the process proceeds to step S4.

  In step S4, following the release of the engine clutch EC in step S3, the rotational speed N1 of the first motor generator MG1 and the second motor generator MG2 so that the inclination of the nomographic chart in the “EV-Low mode” is obtained. , N2 and control goes to step S5.

  In step S5, following the control in which the slope of the nomograph in “EV-Low mode” in step S4 is set, and the rotation speed of the second ring gear R2 that is the input element of the first motor generator MG1 is substantially zero, The brake HLB is engaged and the process proceeds to step S6.

  At step S6, the high-low brake HLB is engaged at step S5, and the second ring gear R2 is fixed to the transmission case TC, so that the mode transitions to the “EV-Low mode” using only the second motor generator MG2 as the drive source. The process proceeds to step S7.

  In step S7, based on the mode transition to “EV-Low mode” in step S6, whether or not the engine speed Ne and the speed ωin of the third rotation member M3 match, that is, the engine speed Ne is It is determined whether or not it matches the lever of the second planetary gear PG2 on the alignment chart. If YES, the process proceeds to step S8, and if NO, the determination in step S7 is repeated.

  In step S8, based on the determination in step S7 that the engine speed Ne and the speed ωin of the third rotating member M3 coincide with each other, the engine clutch EC is engaged, and the engine E and the second motor generator MG2 are driven. The mode transitions to the “HEV-Low mode” that is the source, and then returns.

[Problems when starting with continuously variable transmission ratio mode]
Japanese Patent Application Laid-Open No. 2003-32808 discloses a planetary gear mechanism having four elements and two degrees of freedom in which four input / output elements are arranged on a collinear diagram, and two arranged inside the input / output elements. An input from the engine is assigned to one of the elements, and an output to the drive system is assigned to the other, and the first motor generator and the second motor generator are assigned to the two elements arranged on both outer sides of the inner element, respectively. A coupled hybrid drive is described. As a result, the torque on the motor generator side with respect to the engine output can be reduced to reduce the size thereof, and the energy passing through the motor generator can be further reduced, so that the transmission efficiency as the drive device is improved.

  In this hybrid drive device, as a travel mode, a “continuously variable transmission mode” that travels using an engine and two motor generators, and a low brake are engaged, and the engine and two motor generators or only two motor generators are coupled. For example, a flat road while slowly depressing the accelerator pedal has been configured to generate a low vehicle speed driving force in the “continuously variable transmission mode”. At the time of starting, a smooth start can be ensured while changing the gear ratio steplessly by selecting the “continuously variable transmission mode”.

  However, when selecting “stepless speed change mode” for starting uphill or starting towing, etc., the speed change steplessly changes in the upshift direction to reduce the driving force. Since the driving force output via the gear mechanism does not correspond in a proportional relationship and the driving force is insufficient, for example, a rollback phenomenon occurs in which the vehicle moves backward at the time of starting. Getting worse. Also, for example, even if the driver intends high start acceleration and depresses the accelerator pedal deeply at start, the gear ratio changes steplessly in the upshift direction that reduces the driving force, so that high start acceleration responds to accelerator operation. I can't get sex.

[Mode transition control for high load start]
On the other hand, in the hybrid vehicle mode transition control apparatus according to the first embodiment, when starting with the “continuously variable transmission ratio mode” selected, the start is performed in a high load state by the high load start detection means. When detected (including when starting with rollback, when starting in a situation where rollback such as uphill or towing is predicted, and when starting from a high accelerator opening) The above-mentioned problem has been solved by providing a mode transition control means for high load start corresponding to mode transition from “speed gear ratio mode” to “low-side fixed gear ratio mode”.

  In other words, when there is no rollback in which the vehicle moves backward when starting with the “HEV-Low-iVT mode” selected, the flow proceeds from step S1 to step S2 to return in the flowchart of FIG. It will be repeated, and the selection of “HEV-Low-iVT mode” is maintained.

  Therefore, in the “HEV-Low-iVT mode”, the collinear chart shown in FIG. 7 is obtained. For example, when starting on a flat road while slowly depressing the accelerator, shifting is performed by selecting the “HEV-Low-iVT mode”. While changing the ratio steplessly, the engine torque Teng and the first motor generator torque T1 are summed to increase the vehicle speed while gradually increasing the output torque Tout, thereby ensuring smooth startability.

  On the other hand, when a rollback occurs in which the vehicle moves backward when starting with the "HEV-Low-iVT mode" selected, step S1, step S2, step S3, step S4, step in the flowchart of FIG. The flow proceeds from S5 to step S6 to step S7 to step S8, and the sequence control according to a predetermined procedure is passed from the "HEV-Low-iVT mode" shown in FIG. 7, and the "HEV-Low" shown in FIG. The mode transition to “mode” is executed.

Here, the transition of the sequence control operation will be described with reference to FIGS.
First, FIG. 9 (a) is a collinear diagram showing a situation immediately after starting when starting in the “HEV-Low-iVT mode”. Immediately after starting, the engine torque Teng and the motor generator torques T1, T2 The sum total becomes the output torque Tout, and the output shaft rotation speed tends to rise in the vehicle traveling direction due to the output torque Tout. However, for example, when the vehicle starts on an uphill road with a steep road surface gradient, and the torque from the road surface that causes the vehicle to move backward is larger than the output torque Tout, as shown in the collinear diagram of FIG. In order to generate an output torque Tout (driving force) that is larger than the road load in this state of the “HEV-Low-iVT mode”, the shaft motor speed becomes minus rotation, and the torque of the first motor generator MG1 is further required. .

  Therefore, when it is detected that the output shaft rotational speed is negative, the flow proceeds from step S2 to the flow after step S3, and the "EV-Low mode" is passed, and then the "HEV-Low mode" is entered. The mode is automatically changed.

  In the sequence control of this mode transition, first, as shown in the nomograph of FIG. 9 (c), the engine clutch EC is released when it is detected that the output shaft rotational speed is negative, and at the same time, A negative torque is generated in second motor generator MG2 to control the rotation speed of second motor generator MG2 in the “EV-Low mode” so that the rotation speed of first motor generator MG1 becomes a rotation speed near zero. Control.

  Next, when the rotation speed of the second motor generator MG2 reaches the target rotation speed and the rotation speed of the first motor generator MG1 reaches 0 rpm, the high / low brake HLB is engaged as shown in the alignment chart of FIG. 10 (a). Then, the second ring gear R2 is fixed to the case, thereby shifting to the “EV-Low mode”. Then, the torque of second motor generator MG2 is reversed to a positive torque to avoid rollback.

  Next, the second ring gear R2 fixed to the case is used as a reaction force receiver, and a positive torque is applied to the second motor generator MG2, thereby rotating the output shaft OUT as shown in the collinear diagram of FIG. Start up with "EV-Low mode" after increasing the number. Thereafter, the positive torque of the second motor generator MG2 is increased, and when the engine speed Ne and the rotation speed of the third rotation member M3 coincide on the alignment chart, the engine clutch EC is engaged, and the engine E and the second motor generator MG2 are engaged. Shifts to “HEV-Low mode” with and as the drive source.

  Therefore, when starting with “HEV-Low-iVT mode” selected, it is possible to ensure smooth start performance at low load start without the occurrence of rollback that the vehicle moves backward, and to generate rollback that the vehicle moves backward. It is possible to achieve both of securing startability by avoiding rollback at a certain high load start.

  In addition, at the time of high load start, when the mode transition from the “HEV-iVT mode” to the “HEV-Low mode” is performed, the engine clutch EC is released and the rotational speed control of the first motor generator MG1 and the second motor generator MG2 is performed. Controls the slope of the nomograph to “EV-Low mode” and performs mode transition to “EV-Low mode” using only the second motor generator MG2 as the drive source by sequence control to engage the high-low brake HLB. Therefore, the mode transition shock can be prevented when the high / low brake HLB is engaged.

  Furthermore, at the time of high load start, after the mode transition from the “HEV-iVT mode” to the “EV-Low mode” using the second motor generator MG2 as a drive source by engaging the high / low brake HLB, the engine of the differential device When the rotational speed of the second ring gear R2 that is the input element matches the engine rotational speed Ne, the engine clutch EC is engaged to enter the "HEV-Low mode" in which the engine E and the second motor generator MG2 are the drive sources. Therefore, the mode transition shock due to the engagement of the engine clutch EC can be prevented.

Next, the effect will be described.
In the hybrid vehicle mode transition control apparatus of the first embodiment, the following effects can be obtained.

  (1) It has a differential device in which four or more input / output elements are arranged on the nomograph, and an input from the engine E is input to one of the two elements arranged inside the input / output elements. In addition, an output member to the drive system is assigned to the other, and a driving force combining transmission in which a first motor generator MG1 and a second motor generator MG2 are connected to two elements arranged on both outer sides of the inner element, respectively. Hybrid vehicles equipped with TM have “continuously variable transmission ratio mode” that starts with a continuously variable transmission ratio and “low fixed gear ratio mode” that starts with a low fixed transmission ratio as driving modes. The vehicle is provided with a high load start detecting means for detecting vehicle start in a high load state, and when starting with the "continuously variable transmission ratio mode" selected, the high load start detection means is used for starting in a high load state. Is detected Since the mode transition control means for high load start that changes the mode from “continuously variable gear ratio mode” to “low-side fixed gear ratio mode” is provided, when starting with the continuously variable gear ratio mode selected, It is possible to achieve both the smooth start performance of the vehicle and the startability by avoiding the rollback at the time of high load start.

  (2) A vehicle speed sensor 8 for detecting the rotation speed of the output shaft is provided, and the high-load start detection means detects a negative output rotation speed by the vehicle speed sensor 8 at the start when the “continuously variable transmission mode” is selected. When the vehicle is detected, it is detected that the vehicle starts in a high load state, and therefore it is possible to accurately detect that the vehicle is in a high load start accompanied by the occurrence of rollback using existing sensor information on the vehicle. .

  (3) An engine clutch EC is provided between the engine E and the engine input element of the differential, and one element of the differential is fixed to the transmission case TC to obtain a fixed transmission ratio on the low side. A low-side fixed gear ratio brake is provided, and the high load start corresponding mode transition control means releases the engine clutch EC when the mode transition from the “continuously variable gear ratio mode” to the “low-side fixed gear ratio mode”, The rotation of the first motor generator MG1 and the second motor generator MG2 controls the inclination of the nomograph to the inclination of the “low-side fixed speed ratio mode”, and the motor is controlled by sequence control for engaging the low-side fixed speed ratio brake. The mode transition to the “low-side fixed gear ratio mode” using the generator as the drive source prevents the mode-transition shock when the low-side fixed gear ratio brake is engaged. The

  (4) The high load start corresponding mode transition control means switches from the “continuous speed ratio mode” to the “low side fixed speed ratio mode” using the motor generator as a drive source by engaging the low side fixed speed ratio brake. After the mode transition, the engine clutch EC is engaged when the rotational speed of the engine input element of the differential device and the engine rotational speed Ne coincide with each other, so that the engine E and the motor generator are used as driving sources. Since the mode transition to the “ratio mode” is performed, a mode transition shock due to the engagement of the engine clutch EC can be prevented.

(5) The driving force composite transmission TM is composed of a first planetary gear PG1, a second planetary gear PG2, and a third planetary gear PG3 having two degrees of freedom and three elements on the collinear diagram of the second planetary gear PG2. Are connected to the elements arranged at one end on the collinear diagram of the third planetary gear PG3 and assigned to the engine E, and at one end on the collinear diagram of the second planetary gear PG2. The first motor generator MG1 is assigned to the arranged elements, and the elements arranged at one end on the alignment chart of the first planetary gear PG1 and the elements arranged at one end on the alignment chart of the second planetary gear PG2 And the second motor generator MG2 is allocated, the output shaft OUT is allocated to the elements arranged inside on the collinear diagram of the third planetary gear PG3, and the collinear diagram of the first planetary gear PG1 is allocated. Second rotation of the element arranged at the other end and the element arranged at the other end on the collinear diagram of the third planetary gear PG3 A low brake LB is provided between an element arranged on the nomographic chart of the first planetary gear PG1 and a transmission case TC, to which the second motor generator MG2 is assigned. A high clutch HC is provided between the first planetary gear PG1 and an element arranged on the inner side of the collinear diagram, and the element arranged at one end on the collinear diagram of the second planetary gear PG2 and a transmission case A high / low brake HLB is provided between the TC and the continuously variable transmission ratio mode is obtained by engaging the low brake LB, releasing the high clutch HC, and releasing the high / low brake HLB. The low-side fixed gear ratio mode is the “HEV-Low mode” obtained by engaging the low brake LB, releasing the high clutch HC, and engaging the high / low brake HLB. The corresponding mode transition control means is “HE When starting with "V-Low-iVT mode" selected, if it is detected by the high load start detection means that the vehicle has started under a high load condition, the "HEV-Low-iVT mode" to "HEV-Low mode" The mode transitions to ”, and when starting with the“ HEV-Low-iVT mode ”, which is the low gear side continuously variable transmission ratio mode effective for smooth low-load start, smooth start performance at low load start And ensuring startability by avoiding rollback at the time of high load start can be achieved at a high level.

  As mentioned above, although the mode transition control apparatus of the hybrid vehicle of this invention has been demonstrated based on Example 1, it is not restricted to this Example 1 about a concrete structure, Each claim of a Claim Design changes and additions are allowed without departing from the gist of the invention.

  In the first embodiment, as the high load start detection unit, an example of a unit that detects the start time accompanied by the occurrence of a rollback in which the vehicle moves backward is shown. For example, a road surface inclination sensor, a traction sensor, etc. It may be used as a means to detect when starting in a situation where rollback such as towing is expected, and when starting, the accelerator opening detected value from the accelerator opening sensor exceeds the set opening. It is good also as a means to detect the time of starting from.

  The mode transition control device of the hybrid vehicle according to the first embodiment is an example of a driving force combining transmission having a differential gear configured by three single pinion type planetary gears. For example, Japanese Patent Laid-Open No. 2003-32808 As described in the above, it can be applied to a driving force synthesizing transmission having a differential constituted by a Ravigneaux planetary gear, and even in other differentials, as a running mode, The present invention can be applied to a hybrid vehicle equipped with a driving force combining transmission having a continuously variable transmission ratio mode starting with a continuously variable transmission ratio and a low fixed gear ratio mode starting with a low fixed transmission ratio. .

1 is an overall system diagram showing a drive system and a control system of a hybrid vehicle to which a mode transition control device of Example 1 is applied. FIG. 5 is a collinear diagram showing five driving modes in an electric vehicle mode in the hybrid vehicle of the first embodiment. FIG. 5 is a collinear diagram showing five travel modes in a hybrid vehicle mode in the hybrid vehicle of the first embodiment. It is a figure which shows an example of the driving mode map used for selection of driving modes in the hybrid vehicle of Example 1. 4 is an operation table of an engine, an engine clutch, a motor generator, a low brake, a high clutch, and a high / low brake in “10 travel modes” in the hybrid vehicle of the first embodiment. 6 is a flowchart showing a flow of a mode transition control process corresponding to a high load start that is executed in the integrated controller of the first embodiment. FIG. 4 is a collinear diagram showing “HEV-Low-iVT mode” in the hybrid vehicle of the first embodiment. FIG. 4 is a collinear diagram illustrating a “HEV-Low mode” in the hybrid vehicle of the first embodiment. FIG. 6 is a collinear diagram showing each operation change state before engaging the high / low brake when the mode is changed from the “HEV-Low-iVT mode” to the “EV-Low mode” at the time of high load start in the integrated controller of the first embodiment. In the integrated controller of the first embodiment, when the mode transitions from “HEV-Low-iVT mode” to “EV-Low mode” at the time of high load start, the collinear line indicates each operation change state when the high / low brake is engaged and after the engagement. FIG.

Explanation of symbols

E engine
MG1 1st motor generator
MG2 Second motor generator (motor generator)
OUT Output shaft (output member)
PG1 first planetary gear (first differential)
PG2 Second planetary gear (second differential)
PG3 3rd planetary gear (3rd differential)
EC engine clutch
LB Low brake (first friction engagement element)
HC high clutch (second frictional engagement element)
HLB high / low brake (third friction engagement element, low-side fixed gear ratio brake)
DESCRIPTION OF SYMBOLS 1 Engine controller 2 Motor controller 3 Inverter 4 Battery 5 Hydraulic control apparatus 6 Integrated controller 7 Accelerator opening sensor 8 Vehicle speed sensor 9 Engine speed sensor 10 First motor generator speed sensor 11 Second motor generator speed sensor 12 Third ring gear Rotational speed sensor

Claims (4)

It has a differential device in which four or more input / output elements are arranged on a nomogram, and the input from the engine is driven to one of the two elements arranged inside the input / output element, and the other is driven In a hybrid vehicle provided with driving force combining transmissions, each of which is assigned an output member to a system, and has a first motor generator and a second motor generator connected to two elements arranged on both outer sides of the inner element ,
As the running mode, it has a continuously variable transmission ratio mode that starts with a continuously variable transmission ratio, and a low fixed gear ratio mode that starts with a fixed fixed gear ratio on the low side,
High load start detection means for detecting vehicle start in a high load state is provided,
An engine clutch is provided between the engine and the engine input element of the differential;
One element of the differential is fixed to the case, and a low-side fixed gear ratio brake for obtaining a low-side fixed gear ratio is provided,
When starting with the continuously variable transmission ratio mode selected, if the high load start detecting means detects that the start is in a high load state, the engine clutch is released, and the first motor generator and the second motor generator are released. The rotation speed control of the collinear chart is controlled to the slope of the low-side fixed gear ratio mode, and the motor generator is driven from the continuously variable gear ratio mode by the sequence control for engaging the low-side fixed gear ratio brake. A mode transition control device for a hybrid vehicle, comprising mode transition control means for high load start corresponding to mode transition to a low-side fixed gear ratio mode. In the hybrid vehicle mode transition control device according to claim 1,
An output rotation speed detection means for detecting the rotation speed of the output member is provided,
The high load start detection means detects a vehicle start in a high load state when a negative output speed is detected by the output speed detection means at the time of starting after selecting the continuously variable transmission mode. A mode transition control device for a hybrid vehicle characterized by the above . In the hybrid vehicle mode transition control device according to claim 1 or 2 ,
The high load start corresponding mode transition control means switches the mode from the continuously variable speed ratio mode to the low side fixed speed ratio mode using a motor generator as a drive source by engaging the low side fixed speed ratio brake, and then The mode transition to the low-side fixed gear ratio mode in which the engine and the motor generator are used as the driving sources is performed by engaging the engine clutch when the engine speed of the engine input element matches the engine speed. A mode transition control device for a hybrid vehicle. It has a differential device in which four or more input / output elements are arranged on a nomogram, and the input from the engine is driven to one of the two elements arranged inside the input / output element, and the other is driven A hybrid vehicle having a driving force combining transmission that assigns output members to a system and connects a first motor generator and a second motor generator to two elements arranged on both outer sides of the inner elements. Leave
The driving force combining transmission is composed of a first differential device, a second differential device, and a third differential device having two degrees of freedom and three elements,
An engine is assigned by connecting an element arranged inside on the nomographic chart of the second differential device and an element arranged at one end on the nomographic chart of the third differential device,
A first motor generator is assigned to an element arranged at one end on the nomographic chart of the second differential device,
An element arranged at one end on the collinear diagram of the first differential device and an element arranged at one end on the collinear diagram of the second differential device are connected to allocate a second motor generator,
Assigning output members to elements arranged inward on the nomographic chart of the third differential;
An element arranged at the other end on the collinear diagram of the first differential device and an element arranged at the other end on the collinear diagram of the third differential device are connected by a direct connection element,
A first frictional engagement element is provided between the element arranged on the nomographic chart of the first differential and the transmission case;
A second frictional engagement element is provided between an element to which the second motor generator is assigned and an element arranged inward on the collinear diagram of the first differential ,
A third frictional engagement element is provided between the element arranged at one end on the alignment chart of the second differential and the transmission case;
As the running mode, the first friction engagement element is fastened, the second friction engagement element is released, the low friction continuously variable mode obtained by releasing the third friction engagement element, and the first friction engagement element are engaged. A low gear fixing mode obtained by releasing the second frictional engagement element and fastening the third frictional engagement element ,
High load start detection means for detecting vehicle start in a high load state is provided,
At the start of pre-selecting a kilo over side stepless speed change mode, when it is detected that the start of the high load condition by the high-load starting detection means, a mode from the low side infinite variable speed mode to the low gear fixed mode A mode transition control device for a hybrid vehicle characterized by transitioning.

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