Control device

Abstract

Control device (3) for a vehicle drive device (1), in which a rotating electric machine (12) and a speed-changing mechanism (13) are provided in that order from the side of an internal combustion engine (11) on a power transmission path connecting the internal combustion engine (11) and wheels (15), and in which the speed-changing mechanism (13) is able to change a speed ratio by controlling an engagement state of a switching engagement device (CL1, CL2) included in the speed-changing mechanism, comprising: a switching support control section (41) which, during a downshift where the speed ratio is changed to a higher speed ratio, performs a switching support control to increase the speed of an input-side rotating component (I) of the speed change mechanism (13) by increasing a torque of the rotating electric machine (12) which is transmitted to the input-side rotating component (I); a capability determination section (42) that determines whether the rotating electric machine (12) can output a required input torque (Tn) to increase the speed of the input-side rotating component (I) according to a predetermined target speed change rate (At) or not; a mode selection section (32) which selects a switching mode from a first switching mode and a second switching mode which differs from the first switching mode with respect to at least one condition for initiating downshifting or processing; and a torque compensation section (43) which, when it is determined that the rotating electric machine (12) cannot output the required input torque (Tn), compensates for a shortfall in the required input torque in the shift support control by using at least one output torque of the internal combustion engine (11) or a torque transmitted by the shift engagement device (CL1, CL2) according to the shift mode, in which the first shift mode is an automatic shift mode and the second shift mode is a manual shift mode, or the second shift mode is a mode in which the time required to control downshifting is shorter than in the first shift mode, or a mode in which the acceleration response during downshifting is higher than in the first shift mode. The torque compensation section (43) compensates for the shortfall by using the torque transmitted by the switching engagement device (CL1, CL2) when the first switching mode is selected, and compensates for the shortfall by using at least the output torque of the internal combustion engine (11) when the second switching mode is selected. The capability determination section (42) further determines whether the rotating electric machine (12) and the internal combustion engine (11) together can output the required input torque (Tn) or not, and The torque compensation section (43) further compensates the shortfall by using the torque transmitted by the switching engagement device (CL1, CL2) if it is determined that the required torque cannot be supplied by the combined action of the rotating electric machine (12) and the internal combustion engine (11) when the second switching mode is selected.

Description

TECHNICAL AREA

[0001] The present invention relates to control devices that control a vehicle drive device in which a rotating electric machine and a speed change mechanism are provided in that order from the side of the internal combustion engine on a power transmission path that connects the internal combustion engine and wheels. TECHNICAL BACKGROUND

[0002] A device described in Japanese patent application number 2004-316831 (JP 2004-316831A) (Patent Document 1) is already known as a control device that controls a vehicle drive device such as the one described above. The terms in Patent Document 1 are indicated in brackets “[ ]” in the description of this section, “TECHNICAL BACKGROUND”. This control device causes the rotating electric machine [motor generator 2] to add or absorb torque during a shift operation according to the combination of the direction in which the speed ratio is changed [shifting up or down] and the operating state of the internal combustion engine [whether the engine power is on or off].For example, the control device for performing a downshift when the internal combustion engine is off increases the rotational speed of an input-side rotary component [transmission input shaft 5] of the speed-changing mechanism [automatic transmission 3] by increasing the torque of the rotating electric machine transmitted to the input-side rotary component. Responsive shift control can thus be performed while reducing shift shock.

[0003] However, in the control device of patent document 1, a primary component that increases the rotational speed of the input component for switching assistance during downshifting is limited to the rotating electric machine. Consequently, depending on the operating conditions of the rotating electric machine, sufficient torque may not be output. As a result, the intended control may not be performed correctly, and a sufficient reduction in switching shock may not be achieved. [State of the art][Patent document]

[0004] [Patent document 1] Japanese patent application with publication number 2004-316831 (JP 2004-316831A)

[0005] US 2011 / 0312468A1 discloses a control device for a power transmission device of a vehicle.

[0006] US 2009 / 0118084A1 discloses a method and a device for performing asynchronous switching operations for a hybrid drive.

[0007] DE 10 2010 014 170 A1 discloses a vehicle power transmission control device.

[0008] DE 10 2007 038 773 A1 discloses a method for carrying out a traction-interrupted switching operation in a parallel hybrid vehicle. SUMMARY OF THE INVENTION [Problem to be solved by the invention]

[0009] It is therefore desirable to create a control device capable of performing a proper, responsive downshift even when there is insufficient torque from a rotating electric machine. [Means to solve the problem]

[0010] According to the present invention, a control device for a vehicle drive device has the features of claim 1.

[0011] According to this characteristic configuration, the rotational speed of the input-side rotating component can be increased by the shift support control, at least in cases where the rotating electric machine can deliver the required input torque, according to the target speed change rate. Thus, responsive shift control can be implemented. Even if the rotating electric machine cannot deliver the required input torque, at least the internal combustion engine or the shift engagement device can compensate for the shortfall in input torque. In this case, the primary component compensating for the shortfall in input torque is not always the same, but is determined variably according to the shift mode.This means that the torque compensating for the shortfall in required input torque is variably selected from the output torque of the internal combustion engine and the torque transmitted by the shifting device, according to the shifting mode. Accordingly, the shortfall in required input torque can be appropriately compensated for according to the respective control characteristics of the first and second shifting modes, which differ from each other at least with regard to the condition for initiating downshifting or processing. Thus, a control device can be created that is capable of performing a proper, responsive downshift even in situations where insufficient torque is available from the rotating electric motor.

[0012] The first shift mode is an automatic shift mode, and the second shift mode is a manual shift mode, or a mode in which the time required to control downshifting is shorter than in the first shift mode, or a mode in which the acceleration response during downshifting is higher than in the first shift mode, and the torque compensation section compensates for the shortfall by using the torque transmitted by the shift engagement device when the first shift mode is selected, and compensates for the shortfall by using at least the output torque of the internal combustion engine when the second shift mode is selected.

[0013] In the configuration described above, when the second shift mode is implemented, rapid execution of the shift control or a generally good driving feel is more important than fuel efficiency during vehicle movement compared to when the first shift mode is implemented. Accordingly, when the second shift mode is selected, the shortfall in required input torque is compensated for by using the output torque of the internal combustion engine. This allows the shift control to be executed quickly in a short time while suppressing shift shock. Conversely, when the first shift mode is selected, the shortfall in required input torque is compensated for by using the torque transmitted by the shift engagement device.This allows for a smooth downshift while suppressing a reduction in fuel efficiency.

[0014] The capability determination section further determines whether the rotating electric machine and the internal combustion engine together can output the required input torque or not, and the torque compensation section further compensates for the shortfall by using the torque transmitted by the switching engagement device if it is determined that the required input torque cannot be output by the rotating electric machine and the internal combustion engine together when the second switching mode is selected.

[0015] According to this configuration, when the second switching mode is selected, the shortfall in the required input torque under the condition specified above is further compensated by using the torque transmitted by the switching device. The rotational speed of the input-side rotating component can therefore be increased through the combined action of the rotating electric motor, the internal combustion engine, and the switching device. This allows for responsive downshifting even if the required input torque cannot be supplied by the combined action of the rotating electric motor and the internal combustion engine.

[0016] It is preferred that the capability determination section further determines whether the rotating electric machine can output a lower limit input torque to increase the speed of the input-side rotating component according to a predetermined lower limit speed change rate, and that the torque compensation section compensates for the shortfall by using the torque transmitted by the switching engagement device when it is determined that the rotating electric machine cannot output the lower limit input torque when the first switching mode is selected.

[0017] The torque transmitted to the wheels can fluctuate when the shortfall in required input torque is compensated for by the shift assist device. Therefore, according to the configuration above, the shortfall in required input torque is only compensated by using the torque transmitted by the shift assist device if the rotating electric machine cannot output the minimum input torque. This can minimize the probability of fluctuations in the torque transmitted to the wheels. Conversely, if the rotating electric machine can output the minimum input torque, the speed of the input-side rotating component can be increased according to the minimum speed change rate by the shift assist control using the minimum input torque.This allows for relatively responsive shift control while suppressing torque fluctuations.

[0018] It is preferred that the rotational speed of the input-side rotating component, which is determined according to a vehicle speed and the speed ratio, is a synchronous speed, and that the lower limit speed change rate is set based on a difference between synchronous speeds before and after a change in the speed ratio and an upper limit switching time, which is determined such that a heat generation quantity of the switching input device that slips when the speed ratio is changed is less than or equal to a predetermined acceptable heat generation quantity.

[0019] According to this configuration, a relatively responsive switching control can be implemented, and the heat generation of the switching device can be limited to an acceptable level or less. This can suppress thermal deterioration of the switching device, reduce the need to improve its thermal resistance or to provide a cooling mechanism, and suppress an increase in the manufacturing costs of the drive device being controlled.

[0020] It is preferred that the above control, which allows for proper responsive downshifting even in situations where insufficient torque is available from the rotating electric machine, is applied during power-off downshifting. That is, it is preferred that the torque compensation section performs a control to compensate for the shortfall during the execution of the shift assist control during power-off downshifting when it is determined that the rotating electric machine cannot output the required input torque. BRIEF DESCRIPTION OF THE DRAWINGS [ Fig. 1] Fig. Figure 1 is a schematic diagram showing a general structure of a vehicle drive system. [ Fig. 2] Fig. Figure 2 is a block diagram showing a general structure of a control device. [ Fig. 3] Fig. Figure 3 is a schematic diagram showing an example of a switching characteristic map. [ Fig. 4] Fig. Figure 4 is a flowchart showing the overall processing procedures of a switching support controller. [ Fig. 5] Fig. Figure 5 is a flowchart showing the processing procedures of an initial assignment determination process. [ Fig. 6] Fig. Figure 6 is a flowchart showing the processing procedures of a second assignment determination process. [ Fig. 7] Fig. Figure 7 is a timing diagram showing an example of the operating state of each part during a switching support control. [ Fig. 8] Fig. Figure 8 is a timing diagram showing an example of the operating state of each part during a switching support control. [ Fig. 9] Fig. Figure 9 is a timing diagram showing an example of the operating state of each part during a switching support control. [ Fig. 10] Fig. Figure 10 is a timing diagram showing an example of the operating state of each part during a switching support control. [ Fig. 11] Fig. Figure 11 is a timing diagram showing an example of the operating state of each part during a switching support control. [ Fig. 12] Fig. Figure 12 shows diagrams that illustrate other examples of the switching characteristic map. WAYS TO EXECUTIVE THE INVENTION

[0021] An embodiment of a control device according to the present invention is described with reference to the accompanying drawings. A control device 3 according to the present embodiment controls a drive device 1. The drive device 1 is a vehicle drive device (hybrid vehicle drive device) that drives a vehicle (a hybrid vehicle) that has both an internal combustion engine 11 and a rotating electric machine 12 as a drive force source for wheels 15. The control device 3 according to the present embodiment is described in more detail below. 1. Configuration of the drive device

[0022] The configuration of the drive device, which is controlled by the control device 3, is described. As in Fig. As shown in Figure 1, the drive device 1, according to the present embodiment, comprises the rotating electric machine 12 on a power transmission path connecting the internal combustion engine 11 and the wheels 15, and a speed-changing mechanism 13 between the rotating electric machine 12 and the wheels 15. That is, the drive device 1 comprises the rotating electric machine 12 and the speed-changing mechanism 13, in that order, on the power transmission path connecting the internal combustion engine 11 and the wheels 15. These components are housed in a drive device casing (not shown).

[0023] The internal combustion engine 11 is a motor (gasoline engine, etc.) that is driven by fuel combustion within the engine to produce power. The internal combustion engine 11 is connected to an input shaft I, which serves as an input component of the drive device 1. In this example, an output shaft of the internal combustion engine, for instance, a crankshaft of the internal combustion engine 11, is connected to the input shaft I in such a way that it rotates together with it. The internal combustion engine 11 is connected to the rotating electric machine 12 via the input shaft I. The term "connected to the drive" means the state in which two rotating components are connected to each other in such a way that they are able to transmit a driving force (synonymous with "torque") between them.This concept includes the state in which the two rotating components are connected in such a way that they rotate together, the state in which the two rotating components are connected in such a way that they are able to transmit a driving force between them via one or more transmission components (a shaft, a gear mechanism, a belt, etc.), etc.

[0024] The rotating electric machine 12 has a rotor and a stator and is capable of operating both as a motor (electric motor) and as a generator (electric generator). The rotor of the rotating electric machine 12 is connected to the input shaft I in such a way that it rotates together with it. The rotating electric machine 12 is connected via an inverter device 24 (see Fig. 2) electrically connected to an electricity storage device 25 (a battery, a capacitor, etc.). The rotating electric machine is supplied with electrical power from the electricity storage device 25 to perform power driving, or supplies electrical power generated by a torque of the internal combustion engine 11, etc., to the electricity storage device 25 in order to store the electrical power therein. The input shaft I is a rotating component (input component of the speed-changing mechanism 13) that is connected to the drive of the speed-changing mechanism 13 and is arranged along the power transmission path in the speed-changing mechanism 13 as close as possible to the internal combustion engine 11. In the present embodiment, the input shaft I corresponds to the "input-side rotating component" of the present invention.

[0025] In the present embodiment, the speed-changing mechanism 13 is an automatic staged speed-changing mechanism with multiple switching stages with different speed ratios (gear ratios) that can be changed. To form the multiple switching stages, the speed-changing mechanism 13 has a gear mechanism and several engagement devices (shifting engagement devices) that engage or disengage rotating elements of the gear mechanism. Each of these engagement devices is designed as a friction engagement device capable of transmitting a torque by means of a frictional force generated between meshing components. Multi-disc wet clutches (including brakes), etc., can be used as these engagement devices.The engagement devices of the speed-changing mechanism 13 comprise a first engagement device CL1, a second engagement device CL2, ... In the present embodiment, the speed-changing mechanism 13 forms a switching stage at any given time by bringing two specific of the multiple engagement devices into a direct-connection engagement state and bringing the remaining engagement devices into a non-engagement state. The speed-changing mechanism 13 can form a target switching stage by bringing one specific or three or more specific of the multiple engagement devices into the direct-action engagement state. The speed-changing mechanism 13 is thus able to switch between the multiple switching stages (to change the speed ratio) by controlling the engagement state of each of the multiple switching engagement devices.

[0026] The speed-changing mechanism 13 switches (changes) the speed of the input shaft I based on the speed ratio set for the switching stage to be formed and transmits the switched (changed) speed to an output shaft O. As used herein, the "speed ratio" is a ratio of the speed of the input shaft I to the speed of the output shaft O, which serves as an output-side rotating component of the speed-changing mechanism 13. The output shaft O, which also serves as an output component of the drive device 1, is connected to the right and left wheels 15 via a differential gear unit 14. A torque transmitted to the output shaft O is distributed and transmitted to the two wheels 15 by the differential gear unit 14.The drive device 1 can thus transmit the torque of the internal combustion engine 11 and / or the rotating electric machine 12 to the wheels 15 to move the vehicle. 2. Configuration of the control device

[0027] The configuration of the control device 3 according to the present embodiment is described. As in Fig. As shown in Figure 2, the control device 3, according to the present embodiment, has several functional units and primarily controls the rotating electric machine 12 and the switching devices (CL1, CL2, ...). The several functional units are capable of receiving and transmitting information to each other. The control device 3 is also capable of receiving and transmitting information to an internal combustion engine control unit 21, which controls the internal combustion engine 11. The control device 3 is capable of receiving information regarding the detection results from sensors Se1 to Se5, which are provided in each part of the vehicle.

[0028] The first rotation sensor Se1 is a sensor that detects the rotational speed of the input shaft I (of the internal combustion engine 11 and the rotating electric machine 12). The second rotation sensor Se2 is a sensor that detects the rotational speed of the output shaft O. The control device 3 is able to derive the rotational speed of the wheels 15 and the vehicle speed based on the detection result of the second rotation sensor Se2. The accelerator pedal actuation extent detection sensor Se3 is a sensor that detects the extent of the accelerator pedal actuation. The state-of-charge detection sensor Se4 is a sensor that detects the state of charge (SOC). The control device 3 is able to derive the amount of electricity stored in the electricity storage device 25 based on the detection result of the state-of-charge detection sensor Se4.The lever position detection sensor Se5 is a sensor that detects the position of a (not shown) gearshift lever. For example, the position of the gearshift lever can be selected from a stop position (P position), an automatic drive position (e.g., D position), a neutral position (N position), and a manual drive position (e.g., sequential sport position). In the present embodiment, the vehicle moves when the gearshift lever is in the automatic drive position or the manual drive position.

[0029] The internal combustion engine control unit 21 controls the internal combustion engine 11. The internal combustion engine control unit 21 determines a target torque and a target speed of the internal combustion engine 11 and controls the operation of the internal combustion engine 11 according to these control objectives. In the present embodiment, the internal combustion engine control unit 21 is able to switch between torque control and speed control of the internal combustion engine 11 according to the vehicle's state of motion. Torque control is the control for sending a command of a target torque to the internal combustion engine 11 to cause the torque of the internal combustion engine 11 to follow the target torque.The speed control is the control for sending a command of a target speed to the internal combustion engine 11 and determining a torque, so that the speed of the internal combustion engine 11 is brought closer to the target speed.

[0030] A drive mode determination section 31 is a functional unit that determines the vehicle's drive mode. The drive mode determination unit 31 refers, for example, to a mode selection map (not shown) to determine the drive mode to be implemented by the drive device 1 based on the vehicle speed, the degree of acceleration device actuation, the amount of electricity stored in the electricity storage device 25, etc. In the following embodiment, the drive modes that can be selected by the drive mode determination unit 31 include an electric drive mode (EV mode) and a hybrid drive mode (HEV mode). In the electric drive mode, while the fuel supply to the internal combustion engine 11 is stopped, the torque of the rotating electric machine 12 is transmitted to the wheels 15 to move the vehicle.In hybrid drive mode, while the internal combustion engine 11 outputs a positive torque (a torque in one direction, such that the rotation of the wheels 15 is accelerated in the forward direction of the vehicle), the torque of both the internal combustion engine 11 and the rotating electric machine 12 is transmitted to the wheels 15 to move the vehicle. The present embodiment can be configured such that drive modes other than those mentioned above can be selected.

[0031] A shift mode selection section 32 is a functional unit that selects a shift mode. The shift mode selection section 32 selects a shift mode from a first shift mode and a second shift mode. In the present embodiment, the shift mode selection section 32 selects a shift mode based on a command from the driver. More precisely, the shift mode selection section 32 selects a shift mode based on the position of the shift lever, which is detected by the lever position detection sensor Se5. More precisely, the shift mode selection section 32 selects the first shift mode when the detected position of the shift lever is the automatic transmission position, and selects the second shift mode when the detected position of the shift lever is the manual transmission position. In the present embodiment, the shift mode selection section 32 corresponds to the "mode selection section" of the present invention.

[0032] The first switching mode is an automatic switching mode in which a target switching stage is automatically changed (and consequently a speed ratio is changed) according to a predetermined circuit diagram by a target switching stage determination section 33 described below. In the present embodiment, a storage device, such as a memory contained in the control device 3, stores a switching characteristic map (see Fig. 3) which defines the switching pattern. The switching map defines the switching pattern based on the relationship between the vehicle speed and the acceleration device actuation magnitude or the braking device actuation magnitude and the target shift stage. This switching pattern is defined such that it causes fuel efficiency to be closer to a maximum value at least during one vehicle movement (distance traveled per unit volume of fuel). In the present embodiment, the second switching mode is a switching mode that differs from the first switching mode with respect to the conditions for initiating the shift control.In the present embodiment, the second shift mode is a manual shift mode in which the target shift stage can be changed manually (and consequently the speed ratio can be changed), based on the driver's intention and independent of the shift map defined in the shift map. When the second shift mode is implemented, a shift command (upshift command or downshift command) is issued to an oil pressure control section 35 essentially according to the same shift map as that of the first shift mode and also based on a predetermined shift lever actuation by the driver.

[0033] The term "upshifting" means changing the target gear ratio to a higher gear (to relatively decrease the gear ratio). That is, "upshifting" means changing the target gear ratio to one that is higher than the one before the change (a change in the gear ratio to one that is lower than the one before the change). The term "downshifting" means changing the target gear ratio to a lower gear (to relatively increase the gear ratio). That is, "downshifting" means changing the target gear ratio to one that is lower than the one before the change (a change in the gear ratio to one that is higher than the one before the change).

[0034] The target switching stage determination section 33 is a functional unit that determines a target switching stage according to the circuit diagram defined in the switching characteristic map. The target switching stage determination section 33 takes into account, for example, the exemplary one in Fig. The switching map shown in Figure 3 refers to the vehicle speed and the degree of acceleration device actuation, and determines a target switching stage to be formed by the speed change mechanism 13 based on the vehicle speed and the degree of acceleration device actuation. In the present embodiment, the target switching stage determination section 33 determines a specific switching stage, selected from a first to sixth switching stage, as a target switching stage. Several switching lines are set in the switching map. If the vehicle speed and the degree of acceleration device actuation change, and an operating point on the switching map crosses one of the switching lines, the target switching stage determination section 33 changes the target switching stage. For simplicity, Figure 3 shows... Fig. Figure 3 is an example where both upshifting and downshifting are determined based on a single shift line. However, hysteresis can be provided, and upshifting and downshifting can each be determined based on individual shift lines, i.e., an upshift line and a downshift line. When the target shift stage is changed, a shift command (an upshift command or a downshift command) is issued to the oil pressure control section 35 according to the direction in which the target shift stage is changed.

[0035] A control section 34 for a rotating electric machine is a functional unit that controls the rotating electric machine 12. The control section 34 for a rotating electric machine determines a target torque and a target speed of the rotating electric machine 12 and controls the operation of the rotating electric machine 12 according to these control objectives. In the present embodiment, the control section 34 for a rotating electric machine is capable of switching between torque control and speed control of the rotating electric machine 12 according to the vehicle's state of motion. Torque control is the control for sending a command of a target torque to the electric machine 12 to cause the torque of the rotating electric machine 12 to follow the target torque.The speed control is the control for sending a command of a target speed to the rotating electric machine 12 and determining a torque, so that the speed of the rotating electric machine 12 is brought closer to the target speed.

[0036] The torque that can be output by the rotating electric machine 12 is sometimes limited, depending on the situation in which the rotating electric machine 12 is located. For example, the rotating electric machine 12 may only be able to output torque within or below a maximum torque specified by the data sheet (in both the positive and negative directions). Alternatively, the rotating electric machine 12 may only be able to output torque within or below an upper torque limit determined by the rotational speed of the rotating electric machine 12 and based on its relationship to the maximum output specified by the data sheet (in both the positive and negative directions).The maximum torque and the upper limit torque can vary according to the ambient temperature, the amount of electricity stored in the electricity storage device 25, etc. For example, the maximum torque and the upper limit torque (based on an absolute value) may be reduced if the ambient temperature is less than or equal to a predetermined low-temperature threshold. The maximum torque and the upper limit torque are sometimes individually limited in the positive and negative directions. For example, if the amount of electricity stored in the electricity storage device 25 is less than or equal to a predetermined low-electricity storage quantity threshold, only the maximum torque and the upper limit torque may be reduced in the positive direction.If the amount of electricity stored in the electricity storage device 25 is greater than or equal to a predetermined high-electricity storage threshold, only the maximum torque and the upper limit torque in the negative direction can be reduced (based on an absolute value). The upper and lower limits of the torque that can be output by the rotating electric machine 12 are given in the . Fig. 7, Fig. 8, Fig. 9, Fig. 10 to Fig. 11 shown by dashed lines.

[0037] The oil pressure control section 35 is a functional unit that controls the supply of oil pressure to each engagement device (CL1, CL2, ...). According to the specified target switching stage, the oil pressure control section 35 issues an oil pressure command for each engagement device and controls the oil pressure to be supplied to each engagement device via a hydraulic control device 28. The oil pressure control section 35 is capable of continuously controlling the oil pressure supplied to each engagement device by means of a proportional solenoid, etc., according to the oil pressure command. An increase or decrease in the engagement pressure of each engagement device is thus continuously controlled to regulate the engagement state of each engagement device.For example, the oil pressure control section 35 brings a designated engagement device (a designated engagement device) into the non-engagement state by controlling the oil pressure supplied to the designated engagement device to a value lower than a non-engagement limit pressure. The oil pressure control section 35 brings a designated engagement device into the direct-connection engagement state by controlling the oil pressure supplied to the designated engagement device to a value greater than or equal to an engagement limit pressure. The oil pressure control section 35 brings a designated engagement device into a slip engagement state by controlling the oil pressure supplied to the designated engagement device to a slip engagement pressure greater than or equal to the non-engagement limit pressure and less than the engagement limit pressure.

[0038] The "non-engagement state" means the state in which neither rotation nor torque is transmitted between two engagement components brought into engagement by a designated engagement device. The "direct-link engagement state" means the state in which the two engagement components are engaged in such a way that they rotate together. The "slip engagement state" means the state in which the two engagement components are engaged with a difference in rotation between them, such that they are able to transmit torque. When a designated engagement device is in the slip engagement state, the two engagement components rotate relative to each other, and torque is transmitted from the engagement component with the higher rotational speed to the engagement component with the lower rotational speed.The amount of torque that can be transmitted when a designated engagement device is in the engaged state (a concept encompassing both direct engagement and slip engagement) is determined by the oil pressure supplied to the designated engagement device at that time (the engagement pressure of the designated engagement device). The amount of torque at that time is defined as the torque transmission capacity of the designated engagement device. The torque transmission capacity of each engagement device can be continuously controlled by increasing or decreasing the oil pressure supplied to it.

[0039] In the present embodiment, the oil pressure control section 35, responding to a switching command from the target switching stage determination section 33, controls the oil pressure to be supplied to each engagement device CL1, CL2, ... according to the modified target switching stage. At this point, the oil pressure control section 35 moves one of the engagement devices that was in the direct-connection engagement state prior to switching to the non-engagement state, and moves another engagement device that was in the non-engagement state prior to switching to the direct-connection engagement state via the slip engagement state. In the following description, during a switching stage change as described above, the first engagement device CL1 is moved to the non-engagement state after the switching stage change, and the second engagement device CL2 is moved to the engagement state.The oil pressure control section 35 controls the oil pressure to be supplied to each engagement device for controlling its engagement state, thereby changing the switching stage to be implemented by the speed change mechanism 13.

[0040] A switching support control section 41 is a functional unit that provides switching support control for increasing or decreasing the rotational speed of the input shaft I by increasing or decreasing the torque of the rotating electric machine 12, which is transmitted to the input shaft I during the execution of the switching control for changing the switching stage, to be implemented by the speed-changing mechanism 13. The switching support control section 41 increases or decreases the torque of the rotating electric machine 12 according to the direction in which the switching stage is changed (the direction in which the speed ratio is changed).An imaginary speed of the input shaft I, determined according to the vehicle speed and the speed ratio, is defined as the "synchronous speed Ns," and the synchronous speeds Ns before and after a shift are defined as the "synchronous speed before a shift Nsa" and the "synchronous speed after a shift Nsb," respectively. When downshifting, the synchronous speed after a shift Nsb is higher than the synchronous speed before a shift Nsa. When upshifting, the opposite is true; that is, the synchronous speed after a shift Nsb is lower than the synchronous speed before a shift Nsa.

[0041] During downshifting, the shift support control section 41 increases the rotational speed of the input shaft I by increasing the torque of the rotating electric machine 12, which is transmitted to the input shaft I. An increase in the torque of the rotating electric machine 12 means an increase in torque based on an absolute value (changing the torque in the positive direction). This includes causing the rotating electric machine 12 to output a larger positive torque, or causing it to output a smaller negative torque, or a torque greater than or equal to zero.On the other hand, during upshifting, the shift support control section 41 reduces the speed of the input shaft I by decreasing the torque of the rotating electric machine 12 that is transmitted to the input shaft I. A reduction in the torque of the rotating electric machine 12 means a reduction in torque based on an absolute value (a change in torque in the negative direction). This involves causing the rotating electric machine 12 to output a smaller positive torque or a torque less than or equal to zero, or causing the rotating electric machine to output a larger negative torque.

[0042] The switching support section 41 can rapidly cause the actual speed of the input shaft I to approach the synchronous speed after a switching operation Nsb by executing such switching support control during an execution of the switching control. Thus, responsive switching control can be implemented.

[0043] A capability determination section 42 is a functional unit that determines whether the rotating electric machine 12 can output the required input torque Tn to increase or decrease the rotational speed of the input shaft I according to a predetermined target speed change rate At. As previously described, the torque that can be output by the rotating electric machine 12 is sometimes limited. The capability determination section 42 therefore determines, based on such a torque limitation of the rotating electric machine 12, whether the rotating electric machine 12 can reliably output the required input torque Tn. The capability determination section 42 further determines whether the rotating electric machine 12 and the internal combustion engine 11 can jointly output the required input torque Tn under predetermined conditions.Furthermore, capability determination section 42 determines whether the rotating electric machine 12 can output a lower limit input torque To to increase or decrease the speed of the input shaft I according to a predetermined lower limit speed change rate Ao under predetermined conditions. These functions of capability determination section 42, the required input torque Tn, the lower limit input torque To, the target speed change rate At, the lower limit speed change rate Ao, etc., are described below with reference to the flowcharts of the [reference]. Fig. 4, Fig. 5 to Fig. 6 described in more detail.

[0044] A torque compensation section 43 is a functional unit that compensates for a shortfall in the required input torque Tn during shift support control if the rotating electric machine 12 is determined to be unable to output the required input torque Tn. The torque compensation section 43 compensates for the shortfall in the required input torque Tn by using at least the output torque of the internal combustion engine 11 or the torque transmitted by the shift engagement device (in this example, the second engagement device CL2, which is brought into engagement during shift control).At this point, the torque compensation section 43 does not use the same (fixed) proportions of the output torque of the internal combustion engine 11 and the torque transmitted by the second engagement device CL, regardless of the situation, but uses a distribution that varies according to the switching mode. The torque compensation section 43 has a primary support component determination section 44 and an allocation determination section 45 for appropriately compensating for the shortfall in the required input torque Tn by using at least the output torque of the internal combustion engine 11 or the torque transmitted by the second time-interaction device CL2, according to the switching mode.

[0045] The primary support component determination section 44 is a functional unit that determines a primary component which, in the event that the rotating electric machine 12 is determined to be unable to output the required input torque Tn, compensates for the shortfall in the required input torque Tn during the shift support control (this primary component is referred to herein as the "primary support component Sa"). The primary support component determination section 44 determines the primary support component Sa from the internal combustion engine 11 and the shift intervention device (in this example, the second intervention device CL2) according to the shift mode implemented at the start of the shift support control.This means that the primary support component determination section 44 does not determine the same primary support component Sa regardless of the situation, but performs a variable determination of the primary support component Sa according to the switching mode.

[0046] The allocation determination section 45 is a functional unit that determines the allocation of torque when the rotational speed of the input shaft I is increased or decreased during the shift assist control. Based on the determination result of the possibility determination section 42, the determination of the primary assist component determination section 44, etc., the allocation determination section 45 determines a torque allocation between the rotating electric machine 12 and the primary assist component Sa (the internal combustion engine 11 and / or the secondary engagement device CL2), if necessary.The primary support component determination section 44 and the allocation determination section 45 work together to compensate for the shortfall in the required input torque Tn by using at least the output torque of the internal combustion engine 11 or the torque transmitted by the second engagement device CL2, according to the switching mode. The function of the torque compensation section 43 (of the primary support component determination section 44 and the allocation determination section 45) is described below with reference to the flowcharts of the [reference missing]. Fig. 4, Fig. 5 to Fig. 6 described in more detail. 3. Details of the shift assist control

[0047] Specific details of the shift assist control according to the present embodiment are described. In the present embodiment, the shift assist control is described in particular with regard to the shift assist control during downshifting while coasting (downshifting without power) (assistance control during downshifting without power). "Coasting" means movement in the state in which the acceleration device actuation magnitude is less than or equal to a predetermined reference actuation magnitude (which may be set to any value, for example, 1 to 5%).Each shift assist control process described below is performed by the respective functional units of the control device 3, with the shift assist section 41, the capability determination section 42, and the torque compensation section 43 (the primary assist component determination section 44 and the assignment determination section 45) serving as a core. For simplicity, in this description, the torque transmission capacity of the second engagement device CL2 is referred to as a capacity calculated for the input shaft I. The “torque transmission capacity calculated for the input shaft I” refers to the torque (the torque transmission capacity) after a torque conversion based on the position of the input shaft I according to the position of the second engagement device CL2 on the power transmission path connecting the input shaft I and the output shaft O.

[0048] In the present embodiment, it is assumed that the gearshift lever is in the automatic drive position or the manual drive position and that the vehicle is at least moving. In this case, the vehicle moves in the first shift mode or the second shift mode. In this state, as described in Fig. As shown in Figure 4, it is determined whether or not a downshift request exists (Step #01). That is, based on the determination result of the target shift stage determination section 33 according to the shift diagram defined in the shift map, or on the driver's actuation of the shift lever, it is determined whether or not a downshift command has been issued. If there is no downshift request, i.e., if there is no shift request, or if there is an upshift request (#01: No), the shift assist control (assistance control during a downshift without power) is terminated, and the shift assist control is restarted.

[0049] When a downshift request is received (#01: Yes), it is determined whether the requested drive force D is negative or not (D < 0) (#02). The requested drive force D is the torque required to propel the vehicle when its sign is positive (D > 0). Accordingly, if the requested drive force D is negative, the vehicle is subject to the torque that decelerates the vehicle (the resistance to movement). If the requested drive force D is greater than or equal to zero (#02: No), the downshift assist control (the downshift assist control when downshifting without power) is terminated and restarted.

[0050] If the requested drive force D is negative (#02: Yes), the shift mode selection section 32 determines which shift mode is implemented at that time (#03). More precisely, based on information regarding the shift lever position detected by the shift lever position detection sensor Se5, it determines which of the first and second shift modes has been selected. If the first shift mode has been selected (#04: Yes), the primary support component determination section 44 etc., under this condition, determines the second engagement device CL2 as the primary support component Sa (#05), and the assignment determination section 45 etc. performs a first assignment determination process (#06). On the other hand, if the second shift mode has been selected (#04: No), the primary support component determination section 44 etc.Under this condition, the internal combustion engine 11 (and, depending on the situation, the second engagement device CL2) is the primary support component Sa (#07), and the allocation determination section 45 etc. performs a second allocation determination process (#08).

[0051] As in Fig. As shown in Figure 5, in the first assignment determination process, the possibility determination section 42 first calculates the required input torque Tn (#11). The required input torque Tn is the torque needed to transmit to the input shaft I to increase the speed of the input shaft I according to the predetermined target speed change rate At. The target speed change rate At of the input shaft I is set so that the switching control (specifically, a so-called inertia phase in this case) can be completed within a predetermined target switching time Pt. The target speed change rate At is calculated based on the difference between the synchronous speeds Ns before and after a switching operation and the target switching time Pt. More precisely, the target speed change rate At is calculated by dividing the synchronous speed after a switching operation Nsb minus the synchronous speed before a switching operation Nsa by the target switching time Pt.The required input torque Tn is calculated based on the target speed change rate At calculated in this way and a total inertia J (the sum of the inertia of the rotor of the rotating electric machine 12 and the inertia of the internal combustion engine 11). More precisely, the required input torque Tn is calculated by multiplying the total inertia J and the target speed change rate At.

[0052] The capability determination section 42 then calculates the torque available for assistance, Tam, of the rotating electric machine (#12). The torque available for assistance, Tam, of the rotating electric machine is the portion of the torque that can be output by the rotating electric machine 12, which can be used to increase the speed of the input shaft I for shift assistance. The torque available for assistance, Tam, of the rotating electric machine is calculated based on the torque Tm of the rotating electric machine, the requested driving force D, and the frictional torque Tf of the internal combustion engine 11. The torque Tm of the rotating electric machine is the lesser of the maximum torque and the upper limit torque according to the synchronous speed after a shift, Nsb, for the rotating electric machine 12.The frictional torque Tf is the sliding resistance etc. that occurs when the output shaft (crankshaft etc.) of the internal combustion engine 11 rotates, and has a negative value (Tf < 0). The torque Tam available for assistance from the rotating electric machine is calculated by subtracting the required driving force D from the torque Tm of the rotating electric machine and adding the frictional torque Tf, which has a negative value.

[0053] The capability determination section 42 then determines whether the rotating electric machine 12 can output the required input torque Tn. In this example, capability determination section 42 determines whether, within the torque limitation range, the rotating electric machine 12 can output the required input torque Tn in addition to the torque required to provide the requested driving force D, which has a negative value, and the torque required to compensate for the frictional torque Tf. More precisely, capability determination section 42 determines whether the torque Tam available for assistance from the rotating electric machine is greater than or equal to the required input torque Tn (#13).

[0054] If it is determined that the rotating electric machine 12 can output the required input torque Tn, i.e., if it is determined that the torque Tam available for support from the rotating electric machine is greater than or equal to the required input torque Tn (#13: Yes), the assignment determination section 45 determines a basic assignment pattern as a torque assignment pattern (#17). The basic assignment pattern is a pattern in which only the rotating electric machine 12 is the primary component that provides the required input torque Tn. That is, according to the basic assignment pattern, the rotating electric machine 12 is caused to output all of the required input torque Tn.

[0055] According to this basic assignment pattern, the internal combustion engine 11 causes the input shaft I to experience resistance corresponding to the frictional torque Tf. The torque transmission capacity of the second engagement device CL2 has a value corresponding to the requested driving force D. If the requested driving force D has a negative value, as in this example, the torque transmission capacity of the second engagement device CL2 has a value with the opposite sign (-D). The rotating electric machine 12 outputs the sum of the torque required to maintain the state in which the requested driving force D is transmitted to the wheels 15, the required input torque Tn for shift assistance, and the torque (-Tf) to compensate for the frictional torque Tf. Accordingly, as in Fig. Figure 7 shows that the torque transmitted to the wheels 15 is maintained at the requested driving force D, and in this state the rotational speed of the input shaft I increases at the target speed change rate At to the synchronous speed after a shift Nsb. That is, the responsive downshift is implemented in the target shift time Pt.

[0056] If it is determined that the rotating electric machine cannot output the required input torque Tn, i.e., if it is determined that the torque Tam available for support from the rotating electric machine is less than the required input torque Tn (#13: No), the possibility determination section 42 calculates a limiting speed change rate Ar (#14). The limiting speed change rate Ar is calculated based on the torque Tam available for support from the rotating electric machine and the total inertia J. More precisely, the limiting speed change rate Ar is calculated by dividing the torque Tam available for support from the rotating electric machine by the total inertia J.

[0057] Subsequently, the possibility determination section 42 determines whether the limiting speed change rate Ar is greater than or equal to the lower limiting speed change rate Ao (#15). The lower limiting speed change rate Ao of the input shaft I is set such that the switching control (in particular the inertial phase in this case) can be completed within a predetermined upper limit switching time Pu. The upper limit switching time Pu is determined such that the amount of heat generated by the second engagement device CL2, which is brought into the slip engagement state during the switching control (in the so-called inertial phase), is less than or equal to a predetermined acceptable amount of heat generated Qp. Such an upper limit switching time Pu can be obtained empirically in advance, based, for example, on preliminary experiments, etc., to verify the heat resistance of the second engagement device CL2.The lower limit speed change rate Ao is calculated based on the difference between the synchronous speeds Ns before and after a switching operation and the upper limit switching time Pu. More precisely, the lower limit speed change rate Ao is calculated by dividing the synchronous speed after a switching operation Nsb minus the synchronous speed before a switching operation Nsa by the upper limit switching time Pu.

[0058] In the present embodiment, the lower limit input torque To is the torque required to transmit to the input shaft I to increase the speed of the input shaft I according to the lower limit speed change rate Ao. Accordingly, determining whether the limit speed change rate Ar is greater than or equal to the lower limit speed change rate Ao is equivalent to determining whether the rotating electric machine 12 can output the lower limit input torque To. In this example, determining whether the limit speed change rate Ar is greater than or equal to the lower limit speed change rate Ao is equivalent to determining whether the rotating electric machine 12 can output the lower limit input torque To in addition to the torque for receiving the requested drive force D, which has a negative value, and the torque for compensating the frictional torque Tf.

[0059] If it is determined that the rotating electric machine 12 can output the lower limit input torque To, i.e., if it is determined that the limit speed change rate Ar is greater than or equal to the lower limit speed change rate Ao (#15: Yes), the assignment determination section 45 determines a first special assignment pattern as the torque assignment pattern (#18). The first special assignment pattern is a pattern in which not all of the required input torque Tn can be output, and the rotating electric machine 12 is merely the primary component that provides a portion of the required input torque Tn. That is, according to the first special assignment pattern, the rotating electric machine 12 is caused to output the torque Tam available for support, which is greater than or equal to the lower limit input torque To and less than the required input torque Tn.

[0060] According to the first specific assignment pattern, the internal combustion engine 11 causes the input shaft I to experience resistance corresponding to the frictional torque Tf. The torque transmission capacity of the second engagement device CL2 has a value corresponding to the requested driving force D (-D). The rotating electric machine 12 outputs the sum of the torque required to maintain the state in which the requested driving force D is transmitted to the wheels 15, the torque Tam available for partial shift assistance from the rotating electric machine, and the torque (-Tf) to compensate for the frictional torque Tf. Accordingly, as in Fig. Figure 8 shows that the torque transmitted to the wheels 15 is maintained at the requested driving force D, and in this state the rotational speed of the input shaft I increases to the synchronous speed after a shift Nsb with the limiting speed change rate Ar, which is greater than or equal to the lower limiting speed change rate Ao and less than the target speed change rate At. That is, a relatively responsive downshift is implemented while suppressing shift shock.

[0061] If it is determined that the rotating electric machine 12 cannot output the lower limit input torque To, i.e., if it is determined that the limit speed change rate Ar is lower than the lower limit speed change rate Ao (#15: No), the assignment determination section 45 calculates an engagement device support torque Tac (#16). The engagement device support torque Tac is the torque transfer capacity of the second engagement device CL2, which is used to increase the speed of the input shaft I for shift assistance. The engagement device support torque Tac according to the first assignment determination process is calculated based on the limit speed change rate Ar, the lower limit speed change rate Ao, and the total inertia J.More precisely, the engagement device support torque Tac is calculated by multiplying the limit speed change rate Ar minus the lower limit speed change rate Ao by the total inertia J.

[0062] Assignment Determination Section 45 defines a second special assignment pattern as the torque assignment pattern (#19). This second special assignment pattern is one in which not all of the required input torque Tn can be output, and the rotating electric machine 12 and the second engagement device CL2 are the primary components that supply a portion of the required input torque Tn. That is, according to the second special assignment pattern, Primary Support Component Determination Section 44 defines the second engagement device CL2 as a single primary support component Sa that assists the switching of the rotating electric machine 12.At this point, as can be seen from the description above, the second engagement device CL2 is determined to be the primary support component Sa, provided that the rotating electric machine 12 is determined to be unable to output the lower limit input torque To (#15: No).

[0063] According to this specific allocation pattern, the internal combustion engine 11 causes the input shaft I to experience resistance according to the frictional torque Tf. The rotating electric machine 12 outputs the sum of the torque required to maintain the state in which the requested driving force D is transmitted to the wheels 15, the torque Tam available for partial shift assistance from the rotating electric machine, and the torque (-Tf) to compensate for the frictional torque Tf. The torque transmission capacity of the second engagement device CL2 is the sum of the value (-D) corresponding to the requested driving force D and the engagement device support torque Tac. Accordingly, as shown in Fig. Figure 9 shows the input shaft I speed with the lower limit speed change rate Ao, which is greater than the limit speed change rate Ar, down to the synchronous speed after a shift Nsb. In this case, compared to the case where the second engagement device CL2 does not serve as the primary support component Sa (see the input shaft I speed shown by the dashed line), a relatively responsive downshift is implemented while suppressing thermal degradation of the second engagement device CL2. Since the torque transmission capacity of the second engagement device CL2 is increased by the amount corresponding to the engagement device support torque Tac, the torque transmitted to the wheels 15 is slightly less than the requested driving force D.However, in the present embodiment, a higher priority is given to suppressing the thermal deterioration of the second engagement device CL2, which is obtained by reducing the switching control time.

[0064] As in Fig. As shown in Figure 6, in the second assignment determination process, the required input torque Tn is calculated (#21), the torque Tam available for support from the rotating electric machine is calculated (#22), and it is determined whether the torque Tam available for support is greater than or equal to the required input torque Tn (#23). If it is determined that the torque Tam available for support from the rotating electric machine is greater than or equal to the required input torque Tn (#23: Yes), the basic assignment pattern is determined as the torque assignment pattern (#27). These steps are similar to steps #11 to #13 and #17 of the first assignment determination process.

[0065] If it is determined that the rotating electric machine 12 cannot output the required input torque Tn, i.e., if it is determined that the torque Tam available for assistance from the rotating electric machine is less than the required input torque Tn (#23: No), the possibility determination section 42 calculates an internal combustion engine assistance torque Tae (#24). The internal combustion engine assistance torque Tae is the torque component of the torque that can be additionally output by the internal combustion engine 11, which can be used to increase the rotational speed of the input shaft I for shift assistance. The internal combustion engine assistance torque Tae is calculated based on an internal combustion engine maximum increase torque Tie and the friction torque Tf.The maximum boost torque (Tie) of an internal combustion engine is the maximum value of the torque that can be additionally output by the internal combustion engine 11. More precisely, the boost torque (Tae) of the internal combustion engine is calculated by adding the friction torque (Tf), which has a negative value, to the maximum boost torque (Tie).

[0066] The capability determination section 42 then determines whether the rotating electric machine 12 and the internal combustion engine 11 can jointly output the required input torque Tn. In this example, capability determination section 42 determines whether the internal combustion engine 11 can output the torque corresponding to the difference between the required input torque Tn and the torque Tam available for assistance from the rotating electric machine. This is determined based on the internal combustion engine assistance torque Tae, the required input torque Tn, and the torque Tam available for assistance from the rotating electric machine.More precisely, the capability determination section 42 determines whether the internal combustion engine support torque Tae has a value greater than or equal to the required input torque Tn minus the torque Tam of the rotating electric machine available for support (the required difference value) or not (#25).

[0067] If it is determined that the internal combustion engine 11 can output the torque corresponding to the shortfall of the required input torque Tn, i.e., if it is determined that the internal combustion engine support torque Tae is greater than or equal to the required difference (#25: Yes), the assignment determination section 45 determines a third special assignment pattern as the torque assignment pattern (#28). The third special assignment pattern is a pattern in which the rotating electric machine 12 and the internal combustion engine 11 are the primary components that supply the required input torque Tn. That is, according to the third special assignment pattern, the primary support component determination section 44 includes the internal combustion engine 11 as the primary support component Sa, which assists the switching support of the rotating electric machine 12.According to the third special assignment pattern, the rotating electric machine 12 and the internal combustion engine 11, which work together, are caused to output the total required input torque Tn.

[0068] According to the third special assignment pattern, the internal combustion engine 11 outputs the required input torque Tn minus the torque Tam available for assistance from the rotating electric machine (the required difference). This output torque of the internal combustion engine 11 is the torque after compensation of the friction torque Tf. The rotating electric machine 12 outputs the sum of the torque required to maintain the state in which the requested driving force D is transmitted to the wheels 15 and the torque Tam available for assistance from the rotating electric machine for partial shift assistance. The torque transmission capacity of the second engagement device CL2 is a value (-D) corresponding to the requested driving force D. Accordingly, as in Fig. Figure 10 shows that the torque transmitted to the wheels 15 is maintained at the requested driving force D, and in this state, the speed of the input shaft I increases to the synchronous speed after a shift Nsb at the target speed change rate At. That is, responsive downshifting is implemented at the target shift time Pt. Since the internal combustion engine 11 delivers the predetermined torque, fuel efficiency decreases slightly. However, since the second shift mode is the shift control, which is primarily based on the driver's intention, improved downshift response is given as high a priority as possible in the present embodiment.

[0069] If it is determined that the required input torque Tn cannot be supplied by the combined action of the rotating electric machine 12 and the internal combustion engine 11, i.e., if it is determined that the internal combustion engine support torque Tae is less than the required difference value (#25: No), the assignment determination section 45 calculates the engagement device support torque Tac (#26). The engagement device support torque Tac is the torque transmission capacity of the second engagement device CL2, which is used to increase the speed of the input shaft I for shift assistance.The engagement device support torque Tac of the second assignment determination process is calculated based on the required input torque Tn, the torque Tam available for support from the rotating electric machine, and the internal combustion engine support torque Tae. More precisely, the engagement device support torque Tac is calculated by subtracting both the torque Tam available for support from the rotating electric machine and the internal combustion engine support torque Tae from the required input torque Tn.

[0070] Assignment Determination Section 45 specifies a fourth special assignment pattern as the torque assignment pattern (#29). The fourth special assignment pattern is a pattern in which the rotating electric machine 12, the internal combustion engine 11, and the second engagement device CL2 are the primary components that supply the required input torque Tn. That is, according to the fourth special assignment pattern, Primary Support Component Determination Section 44 includes the second engagement device CL2, in addition to the internal combustion engine 11, as the primary support component Sa, which assists in switching the rotating electric machine 12.According to the fourth special assignment pattern, the rotating electric machine 12, the internal combustion engine 11 and the second engagement device CL2, which work together, are caused to output the total required input torque Tn.

[0071] According to the fourth special assignment pattern, the internal combustion engine 11 outputs the internal combustion engine support torque Tae. The internal combustion engine support torque Tae is obtained as a value where the friction torque Tf (< 0) is balanced (Tae = Tie + Tf). The rotating electric machine 12 outputs the sum of the torque required to maintain the state in which the requested driving force D is transmitted to the wheels 15 and the torque Tam of the rotating electric machine available for partial shifting assistance. The torque transmission capacity of the second engagement device CL2 is the sum of the value (-D) corresponding to the requested driving force D and the engagement device support torque Tac. Accordingly, as in Fig. Figure 11 shows the input shaft speed I being adjusted to the synchronous speed after a shift Nsb at the target speed change rate At. That is, responsive downshifting is implemented at the target shift time Pt. Since the internal combustion engine 11 delivers the predetermined torque, fuel efficiency decreases slightly. Furthermore, because the torque transmission capacity of the second engagement device CL2 is increased by the amount corresponding to the engagement device support torque Tac, the torque transmitted to the wheels 15 is less than the requested drive force D. However, since the second shift mode is the shift control, which is primarily based on the driver's intention, higher priority is given in the present embodiment to improving downshift responsiveness as much as possible.

[0072] As previously described, according to the present embodiment, the control device 3 can suitably determine the primary support component Sa according to the respective control characteristics of the first switching mode, which serves as the automatic switching mode, and the second switching mode, which serves as the manual switching mode. The control device 3 can suitably compensate for the shortfall in the required input torque Tn according to the control characteristics of each switching mode by using at least the output torque of the internal combustion engine 11 or the torque transmitted by the switching engagement device (in this example, the second engagement device CL2), according to the switching mode.Accordingly, the control device 3 can be implemented, which is capable of implementing a suitable, responsive downshift even when insufficient torque from the rotating electric machine 12 is available to provide shift assistance. In particular, considering fuel efficiency during vehicle movement and the suppression of shift shock, etc., excellent overall control characteristics with respect to fuel efficiency, shift shock, responsiveness, etc., can be maintained during downshift control without power, depending on the situation. 4. Other embodiments

[0073] Finally, other embodiments of the control device according to the present invention are described. Configurations disclosed in connection with each of the present embodiments can be suitably combined with those disclosed in connection with other embodiments, provided no contradiction arises.

[0074] (1) The above embodiment was described with reference to an example in which the second switching mode differs from the first switching mode with respect to the condition for initiating the switching control; more precisely, an example in which the first switching mode is the automatic switching mode and the second switching mode is the manual switching mode. However, embodiments of the present invention are not limited thereto. For example, in the case in which both the first and second switching modes are automatic switching modes, the switching map (the circuit diagram) referred to may differ between the first and second switching modes. For example, as in Fig. 12 shows the circuit diagram in the second switching mode ( Fig. 12B) such that the target shift stage for the vehicle speed is in comparison to the shift diagram in the first shift mode ( Fig. 12A) is set on the side of a relatively lower vehicle speed. In such a configuration, the second shift mode is a mode that differs from the first shift mode in terms of the conditions for initiating the shift control and in which an acceleration response during downshifting is higher than in the first shift mode.

[0075] Alternatively, the second shift mode can be a mode that differs from the first shift mode in terms of the processing of the shift control. If both the first and second shift modes are automatic shift modes that reference a common shift map (a common circuit diagram), the primary component that performs the shift assistance control can differ from the outset in the first and second shift modes (the basic assignment pattern can be different). For example, in the second shift mode, the internal combustion engine 11 can also output a certain amount of torque from the outset, and the rotating electric machine 12 and the internal combustion engine 11 can work together from the outset to perform the shift assistance control.In such a configuration, the second switching mode is a mode in which the time required to control downshifting is shorter than in the first switching mode.

[0076] The first and second switching modes can differ from each other with respect to the conditions for initiating the switching control and with respect to the processing. In these configurations, the primary support component Sa can also be appropriately determined according to the respective control characteristics of the first and second switching modes, which differ at least with respect to the conditions for initiating the switching control or the processing. Accordingly, the control device 3 can be implemented, which is capable of performing a suitable, responsive downshift even if insufficient torque from the rotating electric machine 12 is available to be used for switching assistance.

[0077] (2) The above embodiment was described with reference to an example in which, if the rotating electric machine 12 cannot output the required input torque Tn when the first switching mode is selected, the second engagement device CL2 serves as the primary support component Sa if the rotating electric machine 12 cannot even output the lower limit input torque To. However, embodiments of the present invention are not limited to this. For example, in such a case, the second engagement device CL2 can serve as the primary support component Sa in any case, regardless of its relationship to the lower limit input torque To. In this case, the engagement device support torque Tac can be calculated based on the required input torque Tn and the torque Tam of the rotating electric machine available for support.More precisely, the engagement device support torque Tac can be calculated by subtracting the torque Tam of the rotating electric machine available for support from the required input torque Tn. In this way, a certain degree of switching shock can be allowed to prioritize improving downshift response.

[0078] (3) The above embodiment was described with reference to an example in which, if the required input torque Tn cannot be supplied even by the combined action of the rotating electric machine 12 and the internal combustion engine 11 when the second switching mode is selected, the second engagement device CL2 is also added as the primary support component Sa in addition to the internal combustion engine 11. However, embodiments of the present invention are not limited to this. For example, in such a case, the internal combustion engine 11 alone can serve as the primary support component Sa.This means that the second engagement device CL2 may not be included as the primary support component Sa, and the shift assistance can be implemented in a torque range that can be output by the interaction of the rotating electric machine 12 and the internal combustion engine 11. In this way, a reduction in downshift response can be permitted to a certain extent in order to prioritize the suppression of shift shock.

[0079] (4) The embodiment described above relates to a configuration in which the driver selects a shift mode or issues a shift command in manual mode based on the gearshift lever actuation. However, embodiments of the present invention are not limited to this. For example, the driver can select a shift mode or issue a shift command in manual mode based on the input of a switch, etc., which may be provided as hardware or software. That is to say, any configuration can be used as long as the driver's intention to shift or a selection can be input into the control device 3. The same applies to the selection of a drive mode, etc.

[0080] (5) The above embodiment was described with reference to an example in which the drive device 1, which is controlled by the control device 3, is located in Fig.The drive device 1 has the configuration shown in Figure 1. However, embodiments of the present invention are not limited thereto. The drive device 1 can have any specific configuration, as long as the rotating electric machine 12 and the speed-changing mechanism 13 are provided in that order on the power transmission path connecting the internal combustion engine 11 and the wheels 15, starting from the internal combustion engine 11. For example, the drive device 1 can have a disengaging device between the internal combustion engine 11 and the rotating electric machine 12, selectively driving the internal combustion engine 11 and the rotating electric machine 12. The drive device 1 can also have a fluid coupling (e.g., a torque converter, etc.) between the rotating electric machine 12 and the speed-changing mechanism 13.) with a connecting engagement device. The drive device 1 can have a specially provided transmission engagement device at any position between the rotating electric machine 12 and the differential gear unit 14.

[0081] (6) The above embodiment was described with reference to an example in which the speed-changing mechanism 13 is a stepped automatic speed-changing mechanism capable of switching between several gear stages (changing the speed ratio stepwise). A speed-changing mechanism with a planetary gear mechanism and a hydraulic clutch, a so-called dual-clutch speed-changing mechanism, etc., can be used as this stepped automatic speed-changing mechanism. However, embodiments of the present invention are not limited thereto. The speed-changing mechanism 13 can have any specific configuration, as long as the speed-changing mechanism 13 is capable of changing the speed ratio by controlling the engagement state of the switching devices included in the speed-changing mechanism 13.For example, the speed change mechanism 13 can be designed as a continuously variable automatic speed change mechanism with a clutch, etc.

[0082] (7) With regard to other configurations, the disclosed embodiments are merely examples, and embodiments of the present invention are not limited to these. That is to say, configurations not described in the claims of the present application can be suitably modified without departing from the object of the present invention. COMMERCIAL APPLICABILITY

[0083] The present invention can be used for control devices that control a drive device for parallel hybrid vehicles with a single engine. [Description of reference symbols] 1 Drive device (vehicle drive device) 3 Control device 11 Internal combustion engine 12 rotating electric machine 13 Speed ​​change mechanism 15-inch wheel 32 Switching mode selection section (Mode selection section) 41 Shift support control section 42. Possibility Assessment Section 43 Torque compensation section 44 Primary Support Component Determination Section 45 Assignment Determination Section I Input shaft (input-side rotating component) CL1 first intervention device (switching intervention device) CL2 second intervention device (switching intervention device) Ns synchronous speed NSA synchronous speed before a shift Nsb synchronous speed after a switch ΔNs difference between synchronous speed before a switching operation and synchronous speed after a switching operation At target speed change rate Ao lower limit speed change rate Pt target switching time Pu upper limit switching time Tn required input torque To lower limit input torque Tam for supporting available torque of the rotating electric machine Tae internal combustion engine support torque Tac engagement device support torque Qp acceptable heat generation quantity

Claims

[1] Control device (3) for a vehicle drive device (1) in which a rotating electric machine (12) and a speed-changing mechanism (13) are provided in that order from the side of an internal combustion engine (11) on a power transmission path connecting the internal combustion engine (11) and wheels (15) and in which the speed-changing mechanism (13) is able to change a speed ratio by controlling an engagement state of a switching engagement device (CL1, CL2) included in the speed-changing mechanism, comprising: a switching support control section (41) which, during a downshift where the speed ratio is changed to a higher speed ratio, performs a switching support control to increase the speed of an input-side rotating component (I) of the speed change mechanism (13) by increasing a torque of the rotating electric machine (12) which is transmitted to the input-side rotating component (I); a capability determination section (42) that determines whether the rotating electric machine (12) can output a required input torque (Tn) to increase the speed of the input-side rotating component (I) according to a predetermined target speed change rate (At) or not; a mode selection section (32) which selects a switching mode from a first switching mode and a second switching mode which differs from the first switching mode with respect to at least one condition for initiating downshifting or processing; and a torque compensation section (43) which, when it is determined that the rotating electric machine (12) cannot output the required input torque (Tn), compensates for a shortfall in the required input torque in the shift support control by using at least one output torque of the internal combustion engine (11) or a torque transmitted by the shift engagement device (CL1, CL2) according to the shift mode, in which the first shift mode is an automatic shift mode and the second shift mode is a manual shift mode, or the second shift mode is a mode in which the time required to control downshifting is shorter than in the first shift mode, or a mode in which the acceleration response during downshifting is higher than in the first shift mode. The torque compensation section (43) compensates for the shortfall by using the torque transmitted by the switching engagement device (CL1, CL2) when the first switching mode is selected, and compensates for the shortfall by using at least the output torque of the internal combustion engine (11) when the second switching mode is selected. The capability determination section (42) further determines whether the rotating electric machine (12) and the internal combustion engine (11) together can output the required input torque (Tn) or not, and The torque compensation section (43) further compensates the shortfall by using the torque transmitted by the switching engagement device (CL1, CL2) if it is determined that the required torque cannot be supplied by the combined action of the rotating electric machine (12) and the internal combustion engine (11) when the second switching mode is selected. [2] Control device according to claim 1, wherein The capability determination section (42) further determines whether the rotating electric machine (12) can output a lower limit input torque (To) to increase the speed of the input-side rotating component (I) according to a predetermined lower limit speed change rate (Ao), and The torque compensation section (43) compensates for the shortfall by using the torque transmitted by the switching engagement device (CL1, CL2) when it is determined that the rotating electric machine (12) cannot output the lower limit input torque (To) when the first switching mode is selected. [3] Control device according to claim 2, wherein the rotational speed of the input-side rotating component (I), which is determined according to a vehicle speed and the rotational speed ratio, is a synchronous speed (Ns) and the lower limit speed change rate (Ao) is based on a difference between synchronous speeds before and after a change in the speed ratio and an upper limit switching time (Pu) which is determined such that a heat generation quantity of the switching intervention device (CL1, CL2) that slips when the speed ratio is changed is less than or equal to a predetermined acceptable heat generation quantity (Qp). [4] Control device according to one of claims 1 to 3, wherein the torque compensation section (43) performs a control to compensate for the shortfall during an execution of the shift support control during downshifting without power, when it is determined that the rotating electric machine (12) cannot output the required input torque (Tn).

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