JP2013244794A - Hybrid system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To a system excellent in an energy saving property, a vehicle mounting property, and the like as a hybrid system of a vehicle including an engine and two motor generators.SOLUTION: A hybrid system includes a first and a second motor generators 1 and 2, and an engine 3. The engine 3 is linked with a ring gear 11 of a planetary gear mechanism 10, a first motor generator 1 is linked with a sun gear 12 of the planetary gear mechanism 10, and an output shaft 24 coupled with a drive wheel is linked with a carrier 13 of the planetary gear mechanism 10. A second motor generator 2 is linked with the output shaft 24. There is provided an engine brake 41 that stops rotation of the ring gear 11 or the engine 3. When a high driving force is requested in a motor travel region, the second motor generator 2 is operated, and the first motor generator 1 is operated by fastening the engine brake 41.

Description

  The present invention relates to a hybrid system, that is, a vehicle drive system including an engine and a motor as drive sources, and belongs to the field of vehicle drive technology.

  As a vehicle hybrid system for the purpose of saving energy, for example, Patent Document 1 includes an engine and a single motor generator, and obtains a driving force mainly from the engine. Are used as an auxiliary drive source and a regenerative generator during deceleration.

  Further, Patent Document 2 discloses a system including an engine and two motor generators as a hybrid system for further energy saving and placing importance on motor travel. In this hybrid system, an engine and a first motor generator are connected to two rotating elements of a planetary gear mechanism, a driving wheel is connected to another rotating element via a driving shaft, and a speed change mechanism is connected to the driving shaft. It is set as the structure which connected the 2nd motor generator via.

  The second motor generator is used as an electric motor for traveling, and the first motor generator is used as an electric motor for starting the engine and an electric generator for electric power for the second motor generator. Usually, only the driving force of the second motor generator is used. While driving, when the high driving force is required, the engine output is divided into the first motor generator side and the driving shaft side, and the driving force of the second motor generator is assisted while operating the first motor generator as a generator. To drive.

JP 2003-11682 A JP 2005-96574 A

  By the way, in the hybrid system disclosed in Patent Document 2, as described above, the engine output is assisted when a high driving force is required. For further energy saving, only the second motor generator is used. It is desired to expand the motor travel area that travels at a high driving force side. However, for this purpose, it is necessary to increase the size of the second motor generator. As a result, the inverter is also increased in size, leading to deterioration in vehicle mountability and increase in vehicle weight.

  Therefore, the present invention makes it possible to expand the motor travel area to the high driving force side while avoiding the enlargement of the motor generator and the inverter in a hybrid system of a vehicle including an engine and two motor generators. Thus, an object of the present invention is to realize a hybrid system that is excellent in energy saving and vehicle mountability.

  In order to solve the above problems, the present invention is configured as follows.

  First, the invention according to claim 1 includes an engine, first and second motor generators, a differential rotation mechanism including three rotation elements, and a controller, and the first rotation of the differential rotation mechanism. A hybrid system in which an engine is connected to an element, a first motor generator is connected to a second rotating element, a drive shaft is connected to a third rotating element, and the second motor generator is connected to the drive shaft, A brake that stops the rotation of the first rotating element, and an actuator that drives the brake, and the controller controls the actuator to engage the brake in a predetermined operation region of the vehicle. In addition to controlling, the first motor generator is controlled to operate.

  The invention according to claim 2 is the invention according to claim 1, wherein the predetermined operation region is a region where the required driving force is equal to or greater than a predetermined value, and the controller has a lower required driving force side than the predetermined operation region. In this region, the actuator is controlled to release the brake, the first motor generator is controlled to be inactive, and the second motor generator is controlled to operate, while the predetermined operation is performed. In the region, the second motor generator is controlled to operate, the actuator is controlled to engage the brake, and the first motor generator is controlled to operate. Features.

  The invention according to claim 3 is the invention according to claim 1 or 2, wherein the controller transfers the output of the engine to a drive shaft from the engine travel region to travel to the predetermined operation region. Sometimes the engine is controlled to stop and the actuator is controlled to engage the brake to stop the rotation of the first rotating element, and then the first motor generator is started to operate. It is configured as follows.

  According to a fourth aspect of the present invention, in the invention according to the third aspect, when the controller shifts from the engine travel region to the predetermined operation region, the rotation speed of the first rotation element is reduced by stopping the engine. The actuator is configured to control the brake so that the brake is engaged after the rotation speed drops below a predetermined number of revolutions.

  The invention according to claim 5 includes an engine, first and second motor generators, and a differential rotation mechanism including three rotation elements, and the engine is included in the first rotation element of the differential rotation mechanism. A hybrid system in which the first motor generator is connected to the second rotating element, the drive shaft is connected to the third rotating element, and the second motor generator is connected to the drive shaft. The brake includes: a brake that stops rotation of the first rotation element; and a control unit that engages the brake and operates the first motor generator in a predetermined operation region of the vehicle.

  According to the invention of each claim of the present application, the following effects can be obtained by the above configuration.

  First, according to the first aspect of the invention, by operating the second motor generator connected to the drive shaft, the vehicle is driven via the drive shaft by the output. When the brake is engaged to stop the rotation of the first rotating element in the differential rotating mechanism and the first motor generator is operated, the output of the first motor generator is the second of the differential rotating mechanism. Therefore, the vehicle is driven by the output of the first motor generator in the predetermined operation region.

  In particular, when the predetermined operation area is an area where a high driving force is required, the brake is engaged as described above while operating the second motor generator in this area, and the first motor generator is operated. When operated, the driving force from the second motor generator and the driving force from the first motor generator are output to the drive shaft.

  In this case, when the first motor generator is mainly used as an engine starting motor or a generator, and the second motor generator is mainly used as a traveling motor, the first motor generator participates in driving as a traveling motor. As a result, the size of the second motor generator and the inverter can be avoided, and the motor traveling area can be expanded to the high driving force side while suppressing the deterioration of the vehicle mountability and the increase of the vehicle weight. Energy can be achieved.

  According to the second aspect of the present invention, when the predetermined driving region is a region where the required driving force is equal to or greater than a predetermined value, the vehicle is second in a region on the lower required driving force side than the predetermined driving region. It is driven only by the driving force from the motor generator, and in the predetermined operating region, it is driven by the driving force from the second motor generator and the driving force from the first motor generator.

  In other words, the first motor generator operates only when a required driving force is higher than a predetermined value, and therefore the required driving force is low while expanding the motor travel region to the higher required driving force side. Further, the deterioration of efficiency due to the operation of the first motor generator is avoided.

  Further, according to the invention according to claim 3, in addition to the motor travel region as described above, when an engine travel region for traveling by transmitting the output of the engine to the drive shaft is provided, this engine travel region The first motor generator is stopped after the engine is stopped and the brake is engaged to stop the rotation of the first rotating element of the differential rotating mechanism. Since the operation is started, the output of the first motor generator is reliably transmitted to the drive shaft from the second rotating element of the differential rotating mechanism via the third rotating element.

  That is, if the first motor generator is operated in a state where the rotation of the first rotation element of the differential rotation mechanism is not stopped, the first motor generator runs idle or becomes unstable. After stopping the rotation of the first rotating element, the first motor generator is started to operate, so that the output of the first motor generator is reliably transmitted to the drive shaft. Thus, the operating state is surely and smoothly transferred to the predetermined operating region in which is operated.

  Further, according to the invention according to claim 4, as described above, when shifting from the engine travel region to the predetermined operation region in the motor travel region, the first stop is caused by stopping the engine when the brake is engaged. Since the brake is engaged after the rotational speed of the rotating element has dropped below the predetermined rotational speed, deterioration of the brake due to the brake being engaged before the engine speed or the rotational speed of the first rotating element has sufficiently decreased. It is suppressed.

  And according to the invention concerning Claim 5, the effect similar to the invention concerning the said Claim 1 is acquired.

1 is a skeleton diagram showing a structure of a hybrid system according to an embodiment of the present invention. It is a control block diagram of the system. It is a map which shows a control area. It is a flowchart which shows control operation. It is a schematic diagram which shows the control state in each area | region of a driving force control mechanism. It is a schematic diagram of a driving force control mechanism showing another control example. It is a time chart which shows the example of driving | running | working in CD mode. It is a time chart which shows the example of driving | running | working in CS mode.

  Hereinafter, embodiments of the present invention will be described.

  FIG. 1 shows the structure of a hybrid system according to this embodiment. This system includes a first motor generator (hereinafter referred to as “first MG”) 1 that operates as an electric motor and a generator, as well as an electric motor and an electric generator. A second motor generator (hereinafter referred to as “second MG”) 2, an engine 3, a driving force control mechanism 4 to which the first, second MG1, 2 and the engine 3 are connected, and the driving force And a differential wheel 5 driven by the output of the control mechanism 4, and drive wheels (not shown) are connected to axles 6, 6 extending from the differential gear 5 to the left and right. A damper 7 is interposed between the engine 3 and the driving force control mechanism 4.

  The driving force control mechanism 4 includes a planetary gear mechanism 10 having a ring gear 11, a sun gear 12, and a carrier 13 as rotating elements, and the engine 3 is connected to the damper 7 and the first gear in the ring gear 11 of the planetary gear mechanism 10. The first MG 1 is connected to the sun gear 12 via the second transmission shaft 22, and the output shaft 24 is connected to the carrier 13 via the transmission gear train 23.

  The second MG 2 is connected to the output shaft 24 via a third transmission shaft 25 and a reduction gear train 26, and the output shaft 24 is connected to the differential device 5 via a final reduction gear train 27. The output shaft 24 corresponds to a “drive shaft” in the claims.

  Further, the driving force control mechanism 4 is disposed between the ring gear 11 of the planetary gear mechanism 10 and the case 4a of the driving force control mechanism 4 as a frictional engagement element for switching the power transmission path, and the ring gear 11 when engaged. An engine brake 41 for restricting the rotation of the engine 3, that is, the rotation of the engine 3, a direct coupling clutch 42 that is disposed between the sun gear 12 and the carrier 13 and connects the sun gear 12 and the carrier 13 when engaged, A reduction brake 43 that is disposed between the case 4a and stops the rotation of the sun gear 12 at the time of fastening is provided.

  These frictional engagement elements 41 to 43 each have a hydraulic actuator (not shown), and are engaged when operating pressure is supplied from the hydraulic control circuit 44 (see FIG. 2), and when the operating pressure is discharged. To be released.

  Further, as shown in FIG. 2, this hybrid system has a controller 50. The controller 50 has a signal from a vehicle speed sensor 51 for detecting the vehicle speed of the vehicle, the amount of depression of the accelerator pedal, in other words, the required driving force. So that the signal from the accelerator sensor 52 for detecting the engine speed, the signal from the engine speed sensor 53 for detecting the engine speed of the engine 3, and the signal from the remaining capacity sensor 55 for detecting the remaining capacity of the battery 54 are input. It has become.

  Then, the controller 50 fastens or releases the frictional engagement elements 41 to 43 via the engine control module 61 that controls the operation of the engine 3 and the hydraulic control circuit 44 according to the state of the vehicle indicated by each signal. Thus, a control signal is sent to the driving force control module 62 that controls the power transmission state of the driving force control mechanism 4 and the inverter 63 that controls the operation of the first and second MGs 1 and 2 and the charging and discharging of the battery 54, respectively. Is output.

  Although not shown, the controller 50 receives signals from various sensors and switches such as a brake sensor for detecting depression of a brake pedal for deceleration regeneration control in addition to the above sensors. Further, the engine control module 61 and the driving force control module 62 may be integrated so that the engine 3 and the friction elements 41 to 43 are controlled by a single control module.

  Next, the control operation of the hybrid system by the controller 50 will be described.

  As shown in FIG. 3, in this hybrid system, as a driving force control mode, a charge depleting mode (hereinafter referred to as “CD mode”) and a charge / sustaining mode (hereinafter referred to as “CS mode”) are described. ) And are set.

  The CD mode is a mode that is selected when the remaining capacity of the battery 54 is equal to or greater than a predetermined amount, and is a mode in which motor travel is performed in the entire operation region of the vehicle with emphasis on energy saving. As shown in (a), the driving region has a low driving force region A1 in which the required driving force is less than a first predetermined driving force F1 (a function of the vehicle speed above a predetermined vehicle speed), and the required driving force is the first predetermined driving force. It is divided into a high driving force region A2 of F1 or more. In the low driving force region A1, the vehicle travels with only the driving force of the second MG2, and in the high driving force region A2, the vehicle travels with the driving force of the first, second MG1, and 2.

  On the other hand, the CS mode is a mode that is selected when the remaining capacity of the battery 54 is less than the predetermined amount, and the operation region has a second predetermined driving force F2 whose required driving force is larger than the first predetermined driving force F1. A motor travel region A in which the vehicle speed is less than a predetermined vehicle speed V (a function of the required drive force), and an engine travel region B in which the required drive force is less than the second predetermined drive force F2 and the vehicle speed is equal to or greater than the predetermined vehicle speed V. The required driving force is divided into the engine / motor combined travel region C having the second predetermined driving force F2 or more.

  The motor travel region A further includes a low driving force region A1 ′ having a required driving force less than the first predetermined driving force F1, and a high driving force region A2 ′ having a required driving force not less than the first predetermined driving force F1. As in the CD mode, the vehicle travels only with the driving force of the second MG2 in the low driving force region A1 ′, and travels with the driving force of the first, second MG1, and 2 in the high driving force region A2 ′. It is like that.

  The engine travel region B includes a low driving force region B1 having a required driving force smaller than the second predetermined driving force F2 and less than a third predetermined driving force F3, and a required driving force not less than the third predetermined driving force F3. In the low driving force region B1, the engine output is traveled as it is as the driving force of the vehicle, and in the high driving force region B2, the engine output is increased (reducing the rotational speed). It is supposed to run.

  In the above configuration, the controller 50 acquires the remaining capacity of the battery 54 from the remaining capacity sensor 55, selects one of the CD mode and the CS mode, and receives signals from the vehicle speed sensor 51 and the accelerator sensor 52. Based on the indicated vehicle speed and the required driving force, it is determined to which of the driving regions shown in FIG. 3 the current driving state belongs.

  Then, control signals are output to the engine control module 61, the driving force control module 62, and the inverter 63, respectively, so that the running state according to each region is achieved, the operation of the first and second MGs 1 and 2, the engine 3 The operation and control of the engagement and release of the engine brake 41, the direct coupling clutch 42, and the deceleration brake 43 in the driving force control mechanism 4 are performed.

  As described above, the direct coupling clutch 42 is disposed between the sun gear 12 and the carrier 13 of the planetary gear mechanism 10 (see FIG. 1). In FIG. 5, for the sake of convenience, the ring gear 11 and the sun gear 12 are connected. Although the direct coupling clutch 42 is disposed between them, the same operation is achieved in any case.

  Next, a specific operation of the driving force control according to the mode and the operation region will be described with reference to a flowchart of FIG. 4 and a schematic diagram illustrating a power transmission state of the driving force control mechanism 4 of FIG.

  First, in step S1 of the flowchart, the controller 50 inputs signals from the sensors 51 to 53, 55, and in step S2, selects either the CD mode or the CS mode according to the remaining capacity of the battery 54. To do.

  When the CD mode in which the motor running is executed in the entire driving region is selected, next, in step S3, whether or not the driver's requested driving force indicated by the signal from the accelerator sensor 52 is equal to or greater than the first predetermined driving force F1. When the driving state is less than the first predetermined driving force F1 and the driving state is in the low driving force region A1 in FIG. 3A, the engine brake 41, the direct coupling clutch 42, and the deceleration brake 43 are followed according to steps S4 to S6. Are released.

  At this time, as shown in FIG. 5A, the ring gear 11 and the sun gear 12 of the planetary gear mechanism 10 are in a free state, and the driving force control mechanism 4 applies only the driving force from the second MG 2 via the reduction gear train 26. Thus, the output shaft 24 can be output. Therefore, the controller 50 operates only the second MG2 in step S7, and the vehicle is driven by the driving force from the second MG.

  When it is determined in step S3 that the required driving force is equal to or greater than the first predetermined driving force F1 and the driving state is in the high driving force region A2 in FIG. 3A, the controller 50 follows steps S8 to S10. Then, the engine brake 41 is engaged, and the direct coupling clutch 42 and the deceleration brake 43 are released.

  At this time, as shown in FIG. 5B, in the driving force control mechanism 4, the rotation of the ring gear 11 in the planetary gear mechanism 10 is stopped, so that the output of the first MG 1 is transmitted via the sun gear 12 and the carrier 13. The controller 50 can transmit to the output shaft 24, and the controller 50 operates the first MG1 in addition to the second MG2 in step S11. Thus, in addition to the driving force from the second MG2, the driving force from the first MG1 is also output to the output shaft 24, and the vehicle travels with the required high driving force.

  On the other hand, when the CS mode is selected, the controller 50 determines in step S12 whether or not the requested driving force is equal to or greater than a second predetermined driving force F2 that is greater than the first predetermined driving force F1, and the second predetermined driving. If it is less than the force F2, it is further determined in step S13 whether or not the vehicle speed is equal to or higher than a predetermined vehicle speed V. When the vehicle speed is less than the predetermined vehicle speed V, the motor travel control by the steps S3 to S11 is executed as in the case of the CD mode.

  That is, when the required driving force is less than the first predetermined driving force F1 and the driving state is in the low driving force region A1 ′ of FIG. 3B, the engine brake 41, the direct coupling clutch 42, and the deceleration brake 43 are all released. When the vehicle is driven only by the driving force from the second MG (step S7) and the required driving force is equal to or higher than the first predetermined driving force F1 and the driving state is in the high driving force region A2 ′, the engine brake 41 is set. The direct coupling clutch 42 and the deceleration brake 43 are released and the vehicle is driven by adding the driving force from the first MG1 to the driving force from the second MG2 (step S11).

  Further, when the required driving force is less than the second predetermined driving force F2 and the vehicle speed is equal to or higher than the predetermined vehicle speed V, that is, when the driving state is in the engine traveling region B of FIG. 3B, the steps S14 to S21 are performed. The engine running control is executed. First, in step S14, it is determined whether or not the required driving force is equal to or more than a third predetermined driving force F3 that is smaller than the second predetermined driving force F2.

  When the requested driving force is less than the third predetermined driving force F3 and the driving state is in the low driving force region B1 in FIG. 3B, the engine brake 41 and the deceleration brake 43 are released according to steps S15 to S17. Then, the direct coupling clutch 42 is engaged.

  As a result, as shown in FIG. 5C, in the driving force control mechanism 4, the planetary gear mechanism 10 is connected to the ring gear 11 and the sun gear 12, and the whole is integrally rotated. If the engine 3 is operated in this state, the output of the engine 3 is output as it is to the output shaft 24 via the carrier 13 without being increased. Therefore, by operating the engine 3 in step S18, the vehicle is directly driven by the output of the engine 3.

  If it is determined in step S14 that the required driving force is greater than or equal to the third predetermined driving force F3 and the driving state is in the high driving force region B2 in FIG. 3B, the engine brake 41 is followed according to steps S19 to S21. Then, the direct coupling clutch 42 is released and the deceleration brake 43 is engaged.

  At this time, as shown in FIG. 5 (d), the planetary gear mechanism 10 of the driving force control mechanism 4 stops the rotation of the sun gear 12, so that the output of the engine 3 is transmitted from the ring gear 11 through the carrier 13. The output is increased (decelerated) to the output shaft 24 and output. Therefore, by operating the engine in step S22, the vehicle travels with a larger driving force than in the case of the low driving force region B1.

  Furthermore, when it is determined in step S12 that the required driving force is greater than or equal to the second predetermined driving force F2, and the operating state is in the engine / motor combined travel region C of FIG. In accordance with steps S23 to S25, the engine brake 41, the direct coupling clutch 42, and the deceleration brake 43 are all released.

  Next, in step S26, a target driving force to be output to the output shaft 24 is determined from the vehicle speed and the accelerator depression amount, and in step S27, the fuel consumption rate becomes the lowest from a preset fuel consumption rate map of the engine. The output and the rotational speed of the engine 3 are read out, and these are determined as the target output and the target rotational speed. In step S28, a throttle opening command is output to the engine 3 so as to achieve this target output.

  In step S29, the load of the first MG1 acting on the engine 3, that is, the power generation amount of the first MG1, is determined so that the engine speed becomes the target speed under the target output. The first MG 1 is operated so as to obtain this power generation amount.

  At this time, a part of the output of the engine 3 is output to the output shaft 24 via the carrier 13 of the planetary gear mechanism 10, and the other part drives the first MG1 via the sun gear 12, and the first MG1 Is operated as a generator. In step S30, the second MG2 is driven using the generated power of the first MG1.

  In that case, the second driving force output from the second MG 2 to the output shaft 24 and the driving force output from the engine 3 corresponding to the target output to the output shaft 24 become the target driving force. Excess or deficiency of power for driving 2MG2 is adjusted with battery 54 through inverter 63.

  As a result, a driving force controlled to a target driving force equal to or greater than the second predetermined driving force F2 is output to the output shaft 24 by the engine 3 and the second MG2, and the vehicle is requested in step S31. The vehicle travels with a large driving force.

  In the engine direct-coupled travel control and engine deceleration travel control in steps S18 and S22, as shown in FIGS. 5C and 5D, the first and second MGs 1 and 2 are deactivated. As shown in (c ′), in the engine direct-coupled travel control, the first MG1 and / or the second MG2 is operated as an electric motor, and these driving forces are added to the driving force of the engine 3 and output to the output shaft 24. Also good. It is also possible to operate the first MG1 and / or the second MG2 as a generator.

  Further, as shown in FIG. 6 (d ′), in the engine deceleration traveling control, the second MG 2 is operated as an electric motor, and the driving force is added to the driving force of the engine 3 and output to the output shaft 24. Good. It is also possible to operate this second MG2 as a generator.

  Furthermore, in the engine / motor combined driving state in step S30, as shown in FIG. 5E, the first MG1 is operated as a generator, and the second MG2 is driven using the generated power. As shown in (e ′), the second MG 2 may be operated as a generator, the first MG 1 may be driven using the generated power, and the driving force may be added to the driving force of the engine 3.

  Next, a specific example of drive control during travel of the vehicle will be described using the time charts of FIGS.

  First, in the CD mode whose time chart is shown in FIG. 7, in this control example, as indicated by the symbol a, when the vehicle starts, the amount of depression of the accelerator pedal is relatively small, and the required driving force is the first predetermined driving force F1. Therefore, only the second MG2 operates, and the vehicle starts relatively slowly by the driving force of only the second MG2.

  Thereafter, when the accelerator pedal is greatly depressed and the required driving force becomes equal to or greater than the first predetermined driving force F1 (region A2), as shown by the symbol b, the engine brake 41 is engaged and the first MG1 is also operated, Due to the driving forces of the first and second MGs 1 and 2, the vehicle travels with a larger acceleration force than immediately after starting.

  When the accelerator pedal is depressed as the vehicle speed increases and the required driving force falls below the first predetermined driving force F1 (region A1), the engine brake 41 is released and the first MG1 is not activated. Thus, the vehicle is again driven only by the driving force of the second MG2.

  Hereinafter, depending on whether the required driving force is less than or equal to the first predetermined driving force F1, the vehicle travels either in a state driven by only the second MG2 or in a state where the driving force of the first MG1 is added thereto. . During deceleration, the second MG 2 operates as a generator to perform deceleration regeneration as indicated by reference symbol c.

  On the other hand, in the CS mode whose time chart is shown in FIG. 8, the required driving force is less than the second predetermined driving force F2 larger than the first predetermined driving force F1 and the vehicle speed is lower than the predetermined vehicle speed V (region A1 ′). , A2 ′), as in the case of the CD mode, the vehicle is driven by only the second MG2 or the engine brake 41 is engaged depending on whether the required driving force is less than or equal to the first predetermined driving force F1. The motor travels in any state where the driving force of the first MG1 is added to the driving force of the second MG2. In the illustrated example, the vehicle starts with the driving force of the first and second MGs 1 and 2 immediately after starting, and then travels only with the driving force of the second MG2.

  Thereafter, when the accelerator pedal is greatly depressed and the required driving force becomes equal to or greater than the second predetermined driving force F2 (region C) as indicated by the symbol d, the engine 3 operates and the output of the engine 3 is output to the output shaft. The first MG1 operates as a power generator to output to 24, and the second MG2 is driven using the generated power. Therefore, the vehicle is driven by the driving force of the engine 3 and the driving force of the second MG 2, and enters the engine / motor combined driving state.

  The operation start of the engine 3 is performed by operating the first MG1 as a starter motor as indicated by a symbol e, and thereafter operating the first MG1 as a generator as described above.

  When the vehicle speed increases to the predetermined vehicle speed V or more and the required driving force decreases to become less than the second predetermined driving force F2 by the engine / motor combined driving, the vehicle shifts to the engine driving state.

  At that time, while the required driving force is equal to or greater than the third predetermined driving force F3 (area B2), the deceleration brake 43 is engaged, whereby the output of the engine 3 is increased and output to the output shaft 24. Further decreases to less than the third predetermined driving force F3 (area B1), the deceleration brake 43 is released, the direct connection brake 42 is engaged, and the output of the engine 3 is output to the output shaft 24 as it is. The

  In this way, in the engine travel region B, the engine travel is performed with a driving force according to the magnitude of the required driving force. Also in this CS mode, at the time of deceleration, as indicated by the symbol f, after the vehicle speed becomes less than the predetermined vehicle speed V, the second MG 2 operates as a generator and performs deceleration regeneration.

  By the way, in the engine / motor combined travel region C, it is assumed that the vehicle is traveling at a speed lower than the predetermined vehicle speed V, and when the required driving force decreases below the second predetermined driving force F2 in this state, the driving region becomes the motor traveling region A. The engine 3 is deactivated. At this time, if the reduced required driving force is equal to or greater than the first predetermined driving force F1, the operating region becomes the high driving force region A2 'of the motor traveling region A, and the first MG1 starts operating in addition to the second MG2.

  In that case, first, when the engine 3 is deactivated by stopping the fuel supply and ignition, and thereafter the engine speed is reduced to a predetermined speed, the engagement control of the engine brake 41 is controlled as indicated by the symbol g. Be started. Therefore, deterioration of the brake 41 due to the engagement of the engine brake 41 before the engine speed or the rotation speed of the ring gear 11 of the planetary gear mechanism 10 is sufficiently reduced is suppressed.

  Then, after a predetermined time t has elapsed after the start of the engagement control of the engine brake 41 and the rotation of the ring gear 11 of the planetary gear mechanism 10 is completely stopped by the engine brake 41, as indicated by the symbol h, The first MG1 starts operating.

  As a result, the output of the first MG1 is reliably transmitted from the sun gear 12 of the planetary gear mechanism 10 to the output shaft 24 via the carrier 13, and the motor that also operates the first MG1 in addition to the second MG2 from the engine / motor combined running state. The transition to the running state is surely and smoothly performed.

  This control is performed in the same manner when the engine traveling region B where the engine 3 operates shifts to the high driving force region A2 'where the first MG1 of the motor traveling region A operates.

  As described above, according to the hybrid system according to this embodiment, the first MG 1 used as the electric motor for starting the engine 3 and the generator for supplying power to the second MG 2 in the engine / motor combined travel region C is provided. In the high driving force region A2 ′ of the motor traveling region A in the CS mode, it is used for driving the vehicle together with the second MG2. Therefore, the motor travel area A is expanded to the high driving force side while avoiding the increase in size of the second MG2.

  The present invention provides a vehicle hybrid system including an engine and two motor generators. This makes it possible to further save energy while suppressing an increase in vehicle mountability and vehicle weight of the system. In the manufacturing industry field, it may be suitably used.

1 1st motor generator (1st MG)
2 Second motor generator (second MG)
3 Engine 10 Differential rotation mechanism (Planetary gear mechanism)
11 First rotating element (ring gear)
12 Second rotating element (sun gear)
13 Third rotating element (carrier)
41 Brake (Engine brake)
50 controller, control means

Claims (5)

An engine, first and second motor generators, a differential rotation mechanism including three rotation elements, and a controller, wherein the engine is the first rotation element of the differential rotation mechanism, and the second rotation element is The first motor generator is a hybrid system in which a drive shaft is connected to a third rotating element, and the second motor generator is connected to the drive shaft,
A brake for stopping rotation of the first rotating element by fastening;
An actuator for driving the brake,
The controller is configured to control the actuator to engage the brake and control the first motor generator to operate in a predetermined operation region of the vehicle. Hybrid system. The predetermined operation region is a region where the required driving force is a predetermined value or more,
The controller controls the actuator to release the brake and controls the first motor generator to be inoperative in a region on the lower required driving force side than the predetermined operation region, and the second motor generator While controlling the motor generator to operate,
In the predetermined operation range, the second motor generator is controlled to operate, the actuator is controlled to engage the brake, and the first motor generator is controlled to operate. The hybrid system according to claim 1, wherein:   The controller controls the engine to stop and engages the brake when shifting from the engine running area where the output of the engine runs to the drive shaft to the predetermined operating area. 3 is configured to control the rotation of the first rotation element by controlling the rotation of the first rotation element and then to start the operation of the first motor generator. Hybrid system.   The controller is configured to engage the brake after the rotation speed of the first rotation element has decreased to a predetermined rotation speed or less due to the stop of the engine when shifting from the engine travel area to the predetermined operation area. The hybrid system according to claim 3, wherein the hybrid system is configured to control. An engine, first and second motor generators, and a differential rotation mechanism having three rotation elements, the engine being the first rotation element of the differential rotation mechanism, and the first motor being the second rotation element The generator is a hybrid system in which a drive shaft is connected to the third rotating element, and the second motor generator is connected to the drive shaft,
A brake for stopping rotation of the first rotating element by fastening;
A hybrid system comprising: a control means for engaging the brake and operating the first motor generator in a predetermined operation region of the vehicle.