HYBRID VEHICLE CONTROL DEVICE

Abstract

Control unit (50) for a hybrid vehicle (90) which has the following features: a machine (13) with an output shaft; a first motor generator (11) with a first output shaft; a second motor generator (12) with a second output shaft; a drive shaft (14) coupled to a drive wheel; a power transmission (100) that combines a force based on the output shaft of the machine (13), a force based on the first output shaft of the first motor generator (11) and a force based on the second output shaft of the second motor generator (12) and outputs the combined force to the drive wheel; a one-way coupling (16) that prevents reverse rotation of the output shaft of the machine (13); and a parking locking mechanism (60) comprising the following: a locking gear (61) designed to rotate together with the drive gear, and a rotation limiter (62) that limits the rotation of the drive shaft (14) when it is engaged with the locking gear (61), wherein the parking lock mechanism (60) is designed to perform a parking lock actuation in order to engage the rotation limiter (62) with the locking gear (61) when a speed change position for the power transmission (100) is set to a park position, the first output shaft of the first motor-generator (11), the output shaft of the machine (13), the drive shaft (14) and the second output shaft of the second motor-generator (12) are shown in this order in a nomogram of the power transmission (100); and a velocity line representing relationships between the first output shaft of the first motor generator (11), the output shaft of the machine (13), the drive shaft (14) and the second output shaft of the second motor generator (12), in which the nomogram is rotatable at the one-way coupling (16), wherein the control unit (50) has the following features: a parking lock completion determination device (51) designed to determine whether the parking lock actuation of the parking lock mechanism (60) is complete, characterized by a parking lock completion driver (53) configured to perform a parking lock completion task when the parking lock completion determining device (51) determines that the parking lock actuation of the parking lock mechanism (60) has not been completed, selectively driving at least one of the first and second motor generators (11, 12) to rotate the drive shaft (14) until the parking lock actuation of the parking lock mechanism (60) is completed; and a malfunction detection device (52) designed to determine whether at least one of the first and second motor generators (11, 12) had a malfunction in order not to rotate in an instructed direction, wherein If a direction identical to a forward direction of the output shaft of the machine (13) is defined as a forward direction of rotation, the park lock completion driver (53) is designed to then, when the first motor generator (11) is selected for the park lock completion task, cause the first motor generator (11) to generate a torque in a reverse direction of rotation opposite to the forward direction of rotation, the torque in the reverse direction rotating the drive shaft (14), and wherein, when it is determined by the malfunction detection device (52) that the first motor generator (11) is operating, although an output of the first motor generator (11) deviates from an instructed value after it is determined by the park lock completion detection device (51) that the park lock actuation of the park lock mechanism (60) is incomplete while the hybrid vehicle (90) is parked, the park lock completion driver (53) is designed to drive the first motor generator (11) to perform the park lock completion task.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on and claims priority from Japanese patent application JP 2016 - 021 872 A, filed on February 8, 2016. TECHNICAL FIELD

[0002] The present disclosure relates to devices for controlling a parking lock mechanism installed in a hybrid vehicle. BACKGROUND

[0003] Hybrid vehicles may include a parking lock mechanism that locks a vehicle's drive shaft when a switch changes its position to the park position. The parking lock mechanism typically drives an actuator to cause a rotation limiter to engage a locking gear fitted to the drive shaft. If the rotation limiter unfortunately fails to engage the locking gear, the vehicle's drive shaft cannot be locked.

[0004] Japanese Patent Application Laid-Open No. 2008-184114, referred to as Patent Document 1, discloses a parking controller installed in a hybrid vehicle having a first motor generator for generating electric power and a second motor generator serving as a main engine for driving the drive shaft of the hybrid vehicle. After the rotation limiter is driven by the parking lock mechanism, the parking controller drives the second motor generator to rotate the drive shaft in the traveling direction of the vehicle. This allows the rotation limiter to reliably engage with the locking gear, thereby reliably preventing the hybrid vehicle from rolling. JP 3 852 562 B2 and JP 5 765 596 B2 disclose four-axis power transmissions for power input and output. DE 11 2005 002 179 T5 discloses further prior art. SUMMARY

[0005] As described above, the above parking control device supplements the locking operation of the parking lock mechanism. The above parking mechanism is applied to the hybrid vehicle having the first motor generator for generating power and the second motor generator serving as the main engine for driving the drive shaft.

[0006] This means that the preceding parking control unit unfortunately only performs a control pattern that complements or supplements the locking operation or locking actuation of the parking lock mechanism.

[0007] This may include difficulty in performing various control patterns that complement the locking operation of the parking lock mechanism using at least one of the first and second motor generators.

[0008] In view of the above-mentioned circumstances, it is an object of the present invention to provide devices for controlling a parking lock mechanism installed in a hybrid vehicle, each of which is designed to solve the above-mentioned problem.

[0009] In particular, another object of the present invention aims to provide such devices, each of which is capable of performing various control patterns that complement a locking operation of the parking lock mechanism using at least one of a first motor generator and a second motor generator.

[0010] The above objects are achieved by a control device for a hybrid vehicle according to claim 1.

[0011] The above objects are further achieved by a control device for a hybrid vehicle according to claim 4.

[0012] The control devices according to the invention make it possible to reliably complete the parking lock operation of the parking lock mechanism even if it is determined that the parking lock operation of the parking lock mechanism has not been completed.

[0013] Further advantageous embodiments are disclosed in the dependent claims.

[0014] The foregoing and / or other features and / or advantages of various aspects of the present disclosure will be further appreciated in consideration of the following description taken in conjunction with the appended drawings. Various aspects of the present disclosure may include and / or exclude various features and / or advantages, as appropriate. Additionally, various aspects of the present disclosure may combine one or more features of other embodiments, as appropriate. The descriptions of features and / or advantages of particular embodiments should not be construed as limiting the other embodiments or the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Other aspects of the present disclosure will become apparent from the following description of an embodiment with reference to the accompanying drawings in which: Fig. 1 is an example of an overall configuration diagram of a hybrid vehicle to which a hybrid control apparatus according to a present embodiment of the present disclosure is applied; Fig. 2A is a diagram schematically illustrating forward rotation of an output shaft, to which a one-way clutch is mounted, of a machine used in Fig. 1 is shown; Fig. 2B is a diagram schematically illustrating that the one-way clutch prevents reverse rotation of the output shaft; Fig. 3A is a nomogram schematically illustrating a parking lock supplement task performed by a first motor generator arranged in Fig. 1 is shown; Fig. 3B is a nomogram schematically illustrating the parking lock supplement task performed by a second motor generator located in Fig. 1; and Fig. 4 is a flowchart schematically illustrating a parking lock supplement control routine executed by the hybrid controller according to the present embodiment. DETAILED DESCRIPTION OF AN EMBODIMENT

[0016] The following describes a present embodiment of the present disclosure with reference to the attached drawings.

[0017] A hybrid vehicle 90 according to the present embodiment includes a first motor generator (MG) 11, a second MG 12, and an internal combustion engine (referred to simply as an engine) 13; each of the first MG 11, the second MG 12, and the engine 13 serves as a power source for driving the hybrid vehicle 90. For example, the present embodiment uses a three-phase permanent magnet synchronous motor as each of the first and second MGs 11 and 12.

[0018] For example, each of the first and second MGs 11 and 12 includes a stator and a rotor rotatable relative to the stator. The rotor has at least one pair of permanent magnets and a longitudinal axis (d-axis) aligned with a direction of magnetic flux generated by an N-pole of the at least one pair of permanent magnets. The rotor also has a transverse axis (q-axis) with a phase aligned with a corresponding d-axis during rotation of the rotor. In other words, the q-axis is electromagnetically perpendicular to the d-axis. The d- and q-axes form a dq coordinate system, i.e., a two-phase rotation coordinate system defined relative to the rotor.

[0019] The first MG 11 has an output shaft 110 coupled to the corresponding rotor, and the second MG 12 has an output shaft 120 coupled to the corresponding rotor. That is, each of the first and second MGs 11 and 12 generates a predetermined torque that rotates the corresponding rotor, thereby rotating the corresponding one of the output shafts 110 and 120.

[0020] The first MG 11 mainly serves as a power generator, and the second MG 12 mainly serves as a motor for generating a motive force while they are operating normally, such as while the hybrid vehicle 90 is running normally.

[0021] A battery B, which is an example of a direct current (DC) power source, is shown in Fig. 1. Battery B is a power source for driving the first and second MGs 11 and 12.

[0022] In particular, a first inverter F1 and a second inverter F2 are Fig. 1. The first inverter or rectifier F1 is operable to convert one of a DC power and a three-phase alternating current (AC) power to the other between the battery and the first MG 11, and the second inverter or rectifier F2 is operable to convert one of the DC power and the three-phase AC power to the other between the battery and the second MG 12.

[0023] For example, an MG controller 200 is operable to perform a normal MG control task, such as a known current control task and / or a known torque control task, using pulse width modulation (PWM) of each of the first and second inverters F1 and F2 to control the corresponding one of the first and second MGs 11 and 12. The present embodiment omits detailed descriptions of the normal MG control task because such normal MG control tasks are well-known technologies.

[0024] In addition, Fig. 1 illustrates an engine control unit (ECU) for controlling operations of the engine 13 based on the speed of the hybrid vehicle 90 and the current position or stroke of the accelerator pedal (not shown) of the hybrid vehicle 90. Fig. 1 also omits the illustration of an overall control device for performing overall control of the operating conditions of the first MG 11, the second MG 12, and the engine 13, and omits input and output signals between the engine ECU and the overall control device.

[0025] The hybrid vehicle 90 further includes a power transmission 100. The power transmission 100 combines the output of the engine 13, the output of the first MG 11, and the output of the second MG 12, and supplies the combined output to a drive shaft 14 as torque. The torque of the drive shaft 14 is transmitted to an axle 93 via a differential 92, thereby rotating drive wheels 94 mounted on both ends of the axle 93.

[0026] For example, the power transmission 100 is designed as a four-axis power transmission for power input and output, as disclosed in Japanese Patent Laid-Open Nos. 3852562B2 and 5765596B2, for example. That is, the power transmission 100 has four axes when represented in a nomogram thereof. Note that the power transmission 100, which is designed as a four-axis power transmission, is configured such that the output shaft 110 of the first MG 11, the output shaft 130 of the engine 13, the drive shaft 14, and the output shaft 120 of the second MG 12 are independently expressed on the nomogram of the power transmission 100, that is, the hybrid vehicle 90.

[0027] The power transmission 100 according to the present embodiment is configured such that a first planetary gear mechanism 20 and a second planetary gear mechanism 30 are juxtaposed, while two rotating elements of one of the first and second planetary gear mechanisms 20 and 30 are coupled to two corresponding rotating elements of the other of them.

[0028] Specifically, the first planetary gear mechanism 20 includes a first sun gear 21, a first planetary gear 22, and a first ring gear 23. The first planetary gear 22 is coupled to a pinion gear (not shown) that meshes with both the first sun gear 21 and the first ring gear 23.

[0029] Similarly, the second planetary gear mechanism 30 includes a second sun gear 31, a second planetary gear 32, and a second ring gear 33. The second planetary gear 32 is coupled to a pinion gear (not shown) that meshes with both the second sun gear 31 and the second ring gear 33.

[0030] Fig. 1 illustrates the first and second sun gears 21 and 31 using reference symbol S, the first and second planetary gears 22 and 32 using reference symbol C, and the first and second ring gears 23 and 33 using reference symbol R.

[0031] The machine 13 has an output shaft 130. The output shaft 110 of the first MG 11 is connected to the first sun gear 21.

[0032] The first planetary gear 22 and the second sun gear 31 are coupled to each other, and the coupled first planetary gear 22 and second sun gear 31 are connected to the output shaft 130 of the machine 13.

[0033] The first ring gear 23 and the second planetary gear 32 are coupled to each other, and the first ring gear 23 and the second planetary gear 32, which are coupled, are connected to the input shaft 14. The second ring gear 32 is connected to the output shaft 120 of the second MG 12.

[0034] The foregoing four-axis power transmission 100, whose two rotating elements of one of the first and second planetary gear mechanisms 20 and 30 are coupled to corresponding two rotating elements of the other of them, is configured to transmit power between the engine 13, the first MG 11, the second MG 12, and the drive shaft 14.

[0035] A one-way clutch 16 is mounted on the output shaft 130 of the engine 13. The one-way clutch 16 is operable to prevent reverse rotation of the output shaft 130 of the engine 13. Specifically, the one-way clutch 16 has an input shaft and an output shaft. The input shaft of the one-way clutch 16 is coupled to the drive shaft 14 via the transmission 100, and the output shaft of the one-way clutch 16 is coupled to the engine 13.

[0036] In particular, as in Fig. 2A, the one-way clutch 16 allows the output shaft 130 of the engine 13 to rotate in the forward direction when a forward torque is applied to the input shaft of the one-way clutch 16. In contrast, as shown in Fig. As shown in Figure 2B, the one-way clutch 16 is locked when a reverse torque is applied to the input shaft of the one-way clutch 16, preventing the output shaft 130 of the engine 13 from rotating. That is, the one-way clutch 16 prevents reverse rotation of the output shaft 130 of the engine 13.

[0037] The hybrid vehicle 90 includes a parking lock mechanism 60 mounted on the drive shaft 14. As described in Patent Document 1, which is Japanese Patent Application Laid-Open No. JP 2008-184114 A, the parking lock mechanism 60 includes a locking gear 61 and a rotation limiter, such as a rotation limit gear, 62. The locking gear 61 rotates together with the drive shaft 14. The rotation limiter 62 is operable to engage the locking gear 61, limiting rotation of the drive shaft 14.

[0038] A switch provided in the hybrid vehicle 90 is connected to the transmission 100. The switch is capable of switching its switching position to one of predetermined speed change positions for the transmission 100 when a driver of the hybrid vehicle is operated; the speed change positions include a parking position used when the hybrid vehicle 90 is parked.

[0039] That is, the parking lock mechanism 60 is designed to perform a parking lock operation that engages the rotation limiter 62 with the ratchet gear 61 to prevent the drive shaft 14 from rolling when the switching position of the switch is changed to the parking position from another position.

[0040] The hybrid vehicle 90 includes a hybrid vehicle control unit 50 for mainly controlling the parking lock operation by the parking lock mechanism 60.

[0041] As described in Patent Document 1, if the locking gear and the rotation limiter are incompletely engaged after performing such a parking lock operation, Patent Document 1 discloses a technology that causes the second motor generator to compensate for the parking lock operation. That is, the technology causes the second motor generator to rotate the drive shaft, thereby reliably engaging the rotation limiter with the locking gear. Note that the state in which the locking gear and the rotation limiter are incompletely engaged is referred to as an incomplete parking lock state.

[0042] Let's consider a case where, in the conventional technology disclosed in Patent Document 1, a driver of the corresponding hybrid vehicle attempts to park the hybrid vehicle on a slope while the second motor generator malfunctions and is out of operation. In this case, if the parking lock mechanism is in the incomplete parking lock state, the hybrid vehicle may unintentionally roll down the slope because the second motor generator cannot compensate for the parking lock operation.

[0043] To address the foregoing matter, the hybrid vehicle control unit 50 is specifically designed to perform a task to ensure the parking lock state of the parking lock mechanism 60 using the first MG 11 or the second MG 12.

[0044] To implement the task referred to as a parking lock completion task, the hybrid vehicle 90 includes the one-way clutch 16 and the following functional modules 51 to 53 installed in the hybrid control unit 50. These functional modules 51 to 53 may be implemented as hardware modules, software modules, or hardware / software hybrid modules.

[0045] As described above, the one-way clutch 16, which prevents the output shaft 130 of the engine 13 from rotating in the reverse direction, causes the output shaft 130 to rotate in the reverse direction even when torque from the first MG 11 or the second MG 12 is applied to the output shaft 130. This allows the drive shaft 14 to rotate, reliably engaging the rotation limiter 62 with the lock gear 61.

[0046] Referring to Fig. 1, the hybrid vehicle control unit 50 includes the parking lock completion determination means 51, the MG malfunction determination means 52, and the parking lock completion driver 53. In the drawings and hereinafter, the term "parking lock" is referred to simply as "P-lock."

[0047] The P-lock completion determination device 51 is operable to determine whether the P-lock operation of the P-lock mechanism 60 is complete while the hybrid vehicle 90 is parked. For example, a first sensor S1 may be provided in the hybrid vehicle 90. The first sensor S1, which is indicated by a two-dot chain line in Fig. 1 is capable of measuring whether the locking gear 61 and the rotation limiter 62 are engaged with each other. Then, the P-lock completion determining means 51 can determine whether the P-lock operation of the P-lock mechanism 60 is completed based on the information representing how the locking gear 61 and the rotation limiter 62 are engaged with each other, which is measured by the first sensor S1.

[0048] As another example, a second sensor S2 may be provided in the hybrid vehicle 90. The second sensor S2, indicated by a two-dot chain line in Fig. 1 is capable of measuring, for example, at least one of the rotational position of the locking gear 61, the rotational angular position of the drive shaft 14, and the rotational time of the drive shaft 14. Then, the P-lock completion determining means 51 can determine whether the P-lock operation of the P-lock mechanism 60 is completed using calculations based on the information representing at least one of the rotational position of the locking gear 61, the rotational angular position of the drive shaft 14, and the rotational time of the drive shaft 14 measured by the second sensor S2.

[0049] The sensors S1 and S2 may be installed in the P-lock mechanism 60.

[0050] The MG malfunction determination device 52 is operable to determine the following (1) whether there is a malfunction in the first MG 11, which represents that the first MG 11 cannot rotate the output shaft 110 in a commanded direction, (2) Whether there is a malfunction in the second MG 12, which represents that the second MG 12 cannot rotate the output shaft 12 in a commanded direction.

[0051] For example, the hybrid controller 50 may be connected to the MG controller 200, and the MG malfunction determination device 52 may be configured to measure how each of the first and second MGs 11 and 12 rotates the corresponding one of the output shafts 110 and 120 in response to a corresponding control command direction generated during the normal MG control task performed by the MG controller 200 before parking the hybrid vehicle 90.

[0052] As another example, the MG malfunction determining means 52 may be configured to measure how each of the first and second MGs 11 and 12 rotates the corresponding one of the output shafts 110 and 120 in response to a corresponding control command direction generated after it is determined by the P-lock completion determining means 51 that the P-lock operation of the P-lock mechanism 60 is incomplete while the hybrid vehicle 90 is parked.

[0053] Note that a malfunction in the first MG 11 or the second MG 12 represents that the first MG 11 or the second MG 12 cannot rotate the corresponding one of the output shafts 110 and 120 in a commanded direction generated by the MG controller 200 or the hybrid vehicle controller 50, so that the first MG 11 or the second MG 12 cannot operate based on a P-lock completion task, which will be described later, executed by the P-lock completion driver 53.

[0054] For example, even if the output of the first MG 11 (or the second MG 12) for rotating the output shaft 110 (or the output shaft 120) deviates from a commanded rotation value, if the output of the first MG 11 (or the second MG 12) can rotate the drive shaft 14 in a commanded direction, the MG malfunction determiner 52 may be configured to determine that there are no malfunctions in the first MG 11 (or the second MG 12) and determine that the P-lock completion driver 53 can perform the P-lock completion task.

[0055] The P-lock completion driver 53 performs the P-lock completion task when it is determined by the P-lock completion determiner 51 that the P-lock operation of the P-lock mechanism 60 has not been completed. This drives at least one of the first MG 11 and the second MG 12, thereby rotating the drive shaft 14 until the P-lock operation of the P-lock mechanism 60 is completed. That is, the P-lock completion driver 53 performs the P-lock completion task until it is determined by the P-lock completion determiner 51 that the P-lock operation of the P-lock mechanism 60 is completed.

[0056] Specifically, when it is determined by the P-lock completion determining means 51 that the P-lock operation of the P-lock mechanism 60 has not been completed, and when it is determined by the MG malfunction determining means 52 that there is a malfunction in any one of the first MG 11 and the second MG 12, the P-lock completion driver 53 drives the other of the first MG 11 and the second MG 12, performing the P-lock completion task.

[0057] When it is determined by the P-lock completion determining means 51 that the P-lock operation of the P-lock mechanism 60 has not been completed, and when it is determined by the MG malfunction determining means 52 that there are no malfunctions in each of the first MG 11 and the second MG 12, the P-lock completion driver 53 may simultaneously drive the first MG 11 and the second MG 12, performing the P-lock completion task.

[0058] That is, the P-lock completion task means a task to complement the incomplete P-lock operation to reliably engage the rotation limiter 62 with the locking gear 61.

[0059] Note that when vector control is used, the P-lock completion driver 53 is configured to calculate a Q-axis control command current in the q-axis of the dq coordinate system and generates a torque control command based on the q-axis control command current. Then, the P-lock completion driver 53 controls at least one of the first and second inverters F1 and F2 based on the torque control command, causing at least one of the first and second MGs 11 and 12 to output a torque based on the torque control command.

[0060] Next, the following describes how the rotary elements including the output shaft 110 of the first MG 11, the output shaft 120 of the second MG 12, the output shaft 130 of the engine 13, and the drive shaft 14 operate while performing the P-lock completion task in accordance with Fig. 3A and Fig. 3B is executed. Each of Fig. 3A and Fig. Figure 3B is a nomogram of the power transmission 100, illustrating relationships between the speeds (e.g., RPMs) of respective rotating elements. In each of Fig. 3A and Fig. 3B, reference symbol MG1 represents the output shaft 110 of the first MG 11 and a reference symbol MG2 represents the output shaft 120 of the second MG 12. In addition, in each of Fig. 3A and Fig. 3B, a reference symbol ENG represents the output shaft 130 of the engine 13, and a reference symbol OUT represents the drive shaft 14. A reference symbol OWC represents the one-way clutch 16.

[0061] The following sometimes describes the output shaft 110 of the first MG 11, the output shaft 120 of the second MG 12, or the output shaft 130 of the engine 13 merely as the first MG 11, the second MG 12, or the engine 13.

[0062] The nomogram of each of Fig. 3A and Fig. 3B represents the machine 13 and the drive shaft 14 as the inner two rotating elements and represents the first MG 11 as the machine-side outer rotating element or rotating component. In addition, the nomogram of each of Fig. 3A and Fig. 3B shows the second MG 12 as the drive shaft side outer member. The one-way clutch 16 is located on the output shaft 130 of the engine 13 on the nomogram.

[0063] That is, the power transmission 100 is designed such that the output shaft 110 of the first MG 11, the output shaft 130 of the engine 13, the drive shaft 14, and the output shaft 120 of the second MG 12 are coupled in this order in the nomogram.

[0064] The relationships between the four rotating elements (MG1, ENG, OUT, and MG2), shown in this order on the nomogram, are represented as a linear line called a speed line. The one-way clutch 16 serves as a pivot point, i.e., a support point, for supporting the speed line on the nomogram.

[0065] On the nomogram, the rotation direction of the output shaft 130 of the engine 13 is defined as the forward direction. That is, the rotation direction of a rotating element other than the output shaft 130, which is identical to the rotation direction of the output shaft 130, is defined as the forward rotation direction on the nomogram, so that the rotational speed of the rotating element is positive on the nomogram. In contrast, the rotation direction of a rotating element other than the output shaft 130, which is opposite to the rotational direction of the output shaft 130, is defined as the reverse rotation direction on the nomogram, so that the rotational speed of the rotating element is negative on the nomogram.

[0066] As in Fig. 3A and Fig. 3B, the speed line is shown as a thick solid line on the reference axis, representing the rotational speed, which is zero when all the rotating elements (MG1, ENG, OUT, and MG2) are stopped while the hybrid vehicle 90 is parked. Note that the speed line has a first end representing the rotational speed of the first MG11 and a second end representing the rotational speed of the second MG2 on the alignment chart. The speed line is supported by the one-way clutch 16 to be rotatable at the one-way clutch 16 in the alignment chart.

[0067] The P-lock completion task includes a first control mode, ie, a first control pattern to drive the first MG 11, a second control mode to drive the second MG 12, and a third control mode to drive both the first and second MGs 11 and 12.

[0068] The P-lock completion driver 53 according to the present embodiment performs the first control mode of the P-lock completion task to cause the first MG 11 to generate a predetermined torque in the reverse rotation direction (see negative torque, ie, -Tmg1 in Fig. 3A). This rotates the drive shaft 14, while the speed line in the nomogram of Fig. 3A is held straight while rotating, ie, pivoting, the one-way clutch 16. At this time, the one-way clutch 16 prevents the reverse rotation of the output shaft 110 of the first MG 11 from being transmitted to the output shaft 130 of the engine 13.

[0069] In particular, as indicated by the thick dashed line L1 in Fig. 3, when the first MG 11 generates a predetermined torque in the reverse rotation direction, the speed line in the nomogram of Fig. 3A, the one-way clutch 16 is rotated so that the speed line is inclined, while the first end of the speed line is negatively changed and the second end of the speed line is positively changed. This inclined speed line L1 indicates that the drive shaft 14 is rotated in the forward rotation direction, so that the teeth of the lock gear 61 are pressed against the rotation limiter 62, that is, adjacent forward-side teeth of the rotation limiting gear 62. This therefore results in the P-lock operation of the P-lock mechanism being completed.

[0070] The P-lock completion driver 53 according to the present embodiment also performs the second control mode of the P-lock completion task to cause the second MG 12 to generate a predetermined torque in the forward rotation direction (see positive torque, ie, Tmg2, in Fig. 3B). This rotates the drive shaft 14, while the speed line in the nomogram of Fig. 3B is held straight while it is rotated or pivoted on the one-way clutch 16.

[0071] In particular, as indicated by the thick dashed line L2 in Fig. 3B, when the second MG 12 generates a predetermined torque in the forward rotation direction, the speed line in the nomogram of Fig. 3B, the one-way clutch 16 is rotated such that the speed line is inclined, while the first end of the speed line is changed negatively and the second end of the speed line is changed positively. This inclined speed line L2 shows that the drive shaft 14 is rotated in the forward rotation direction, so that the teeth of the lock gear 61 are pressed against the rotation limiter 62, that is, adjacent forward-side teeth of the rotation limit gear 62. This therefore results in the P-lock operation of the P-lock mechanism 60 being completed.

[0072] Additionally, the P-lock completion driver 53 according to the present embodiment is capable of performing the third control mode of the P-lock completion task to cause the first MG 11 to generate torque in the reverse direction and the second MG 12 to generate torque in the forward rotation direction. This can also result in the P-lock operation of the P-lock mechanism 60 being completed.

[0073] Next, the following describes a P-lock completion control routine executed by the hybrid vehicle control unit 50 with reference to the flowchart of Fig. 4 is executed. The hybrid vehicle control unit 50 executes the P-lock completion control routine when the P-lock mechanism 60 starts the P-lock operation.

[0074] When the P-lock completion control routine starts, the P-lock completion determining means 51 of the hybrid vehicle control apparatus 50 determines whether the P-lock operation of the P-lock mechanism 60 is completed in step S1.

[0075] If it is determined that the P-lock operation of the P-lock mechanism 60 is completed (YES in step S1), the P-lock completion driver 53 of the hybrid vehicle controller 50 determines that there is no need to perform the P-lock completion task. Then, the P-lock completion driver 53 of the hybrid vehicle controller 50 sets the torque control command for each of the first and second MGs 11 and 12 to zero in step S8, and thereafter, the hybrid vehicle controller 50 terminates the P-lock completion control routine.

[0076] On the other hand, if it is determined that the P-lock operation of the P-lock mechanism 60 has not been completed (NO in step S1), the P-lock completion driver 53 of the hybrid vehicle control unit 50 determines that there is a need to perform the P-lock completion task. Then, the hybrid vehicle control unit 50 performs the following operations in steps S2 to S7 to determine at least one of the first and second MGs 11 and 12 to be used to perform the P-lock completion task.

[0077] Specifically, following the negative determination in step S1, the MG malfunction determining means 52 of the hybrid vehicle control device 50 determines whether both the first and second MGs 11 and 12 are operating normally, i.e., cleanly, in step S2. In other words, the MG malfunction determining means 52 of the hybrid vehicle control device 50 determines whether there is no malfunction in each of the first and second MGs 11 and 12 in step S2.

[0078] When it is determined that both the first and second MGs 11 and 12 are operating normally (YES in step S2), the P-lock completion control routine proceeds to step S3.

[0079] In step S3, the P-lock completion driver 53 of the hybrid vehicle control device 50 executes one of the first to third control modes to output a torque control command based on the corresponding one of the first to third control modes to the corresponding at least one of the first and second MG 11 and MG 12 for completing the P-lock operation of the P-lock mechanism 60.

[0080] Specifically, the P-lock completion driver 53 of the hybrid vehicle control unit 50 selects one of the following: (1) the first control mode to drive only the first MG 11 by a predetermined angle in the reverse rotation direction, ie, rotate, (2) the second control mode to drive only the second MG 12 by a predetermined angle in the forward rotation direction, ie, to rotate, 3) the third control mode to simultaneously perform rotation of the first MG 11 by a predetermined angle in the reverse rotation direction and rotation of the second MG 12 by a predetermined angle in the forward rotation direction.

[0081] When it is determined that either the first or second MG 11 and 12 is not operating normally (NO in step S2), the MG malfunction determining means 52 of the hybrid vehicle control apparatus 50 determines whether the first MG 11 is operating normally and the second MG 12 has malfunctioned in step S4.

[0082] When it is determined that the first MG 11 is operating normally and the second MG 12 has malfunctioned (YES in step S4), the P-lock completion driver 53 executes the first control mode to output a torque control command based on the first control mode to the first MG 11 for complementing the P-lock operation of the P-lock mechanism 60 in step S5.

[0083] On the other hand, when the foregoing determination that the first MG 11 is operating normally and the second MG 12 has malfunctioned is not satisfied (NO in step S4), the MG malfunction determining means 52 of the hybrid vehicle control apparatus 50 determines whether the first MG 11 has malfunctioned and the second MG 12 is operating normally in step S6.

[0084] When it is determined that the first MG 11 has malfunctioned and the second MG 12 is operating normally (YES in step S6), the P-lock completion driver 53 executes the second control mode to output a torque control command based on the second control mode to the second MG 12 for complementing the P-lock operation of the P-lock mechanism 60 in step S7.

[0085] Note that the hybrid vehicle control unit 50 may first perform the determination in step S6 and then perform the determination in step S4 next.

[0086] After the operation in step S3, S5, or S7, the P-lock completion control routine preferably proceeds to step S1, and the hybrid vehicle controller 50 performs the operations in steps S1 to S8 until the determination in step S1 is affirmative and the operation in step S8 is performed.

[0087] When the foregoing determination that the first MG 11 has malfunctioned and the second MG 12 is operating normally is not met (NO in step S6), that is, when both the first and second MGs 11 and 12 have malfunctioned (NO in all steps S2, S4, S6), the P-lock completion driver 53 of the hybrid vehicle control unit 50 determines that it is difficult to perform the P-lock completion task. Then, the P-lock completion driver 53 of the hybrid vehicle control unit 50 sets the torque control command for each of the first and second MGs 11 and 12 to zero in step S8, and thereafter, the hybrid vehicle control unit 50 terminates the P-lock completion control routine.

[0088] It should be noted, however, that the probability of malfunctions in both the first and second MG 11 and 12 appears very low.

[0089] Specifically, in step S3, the P-lock completion driver 53 may only drive the first MG 11 to perform the P-lock completion task if it is determined that at least the first MG 11 is operating properly. In other words, the P-lock completion driver 53 may use the first MG 11 to perform the P-lock completion task in principle, and may use the second MG 12 to perform the P-lock completion task only if the first MG 11 has malfunctioned.

[0090] Additionally, in step S3, the P-lock completion driver 53 may drive only the second MG 12 to perform the P-lock completion task if it is determined that at least the second MG 12 is operating properly. In other words, the P-lock completion driver 53 may use the second MG 12 to perform the P-lock completion task in principle, and may use the first MG 11 to perform the P-lock completion task only if the second MG 12 has malfunctioned.

[0091] As described above, the hybrid vehicle control apparatus 50 is applied to the hybrid vehicle 90 equipped with the first and second MGs 11 and 12 and the one-way clutch 16 for preventing reverse rotation of the output shaft 130 of the engine 13.

[0092] Specifically, the hybrid vehicle control unit 50 is configured to use at least a torque from the first MG 11 in the reverse direction and a torque from the second MG 12 in the forward direction to rotate the drive shaft 14, making it possible to complete the P-lock operation of the P-lock mechanism 60.

[0093] Even when the P-lock operation of the P-lock mechanism 60 has not been completed so that the lock gear 61 and the rotation limiter 62 are incompletely engaged while the hybrid vehicle 90 is parked, the hybrid vehicle control unit 50 selectively drives at least one of the first and second MGs 11 and 12 to reliably engage the lock gear 61 and the rotation limiter 62 with each other.

[0094] That is, the hybrid vehicle control device 50 is capable of selectively performing one of the first to third control modes to reliably complete the P-lock operation of the P-lock mechanism 60. This enables the various control modes, that is, control patterns that complete the P-lock operation of the P-lock mechanism 60, to be implemented, compared to the single control pattern of the P-lock mechanism disclosed in Conventional Patent Document 1.

[0095] Specifically, the hybrid vehicle control unit 50 includes the MG malfunction determination means 52 for determining whether there is a malfunction in at least one of the first and second MGs 11 and 12. This configuration enables the hybrid vehicle control unit 50, even if there is a malfunction in one of the first and second MGs 11 and 12, to drive the other of the first and second MGs 11 and 12 to perform the P-lock completion task.

[0096] The following describes a specific effect based on this configuration of the hybrid vehicle control unit 50 in the situation where a driver of the hybrid vehicle 90 parks the hybrid vehicle 90 on a slope to call a mechanic or repair shop when it is determined that the second MG 12 is malfunctioning so as not to be driven. In this situation, if the P-lock operation of the P-lock mechanism 60 has not been completed, so that the locking gear 61 and the rotation limiter 62 are not fully engaged, the hybrid vehicle control unit 50 performs the P-lock completion task using the appropriate operation of the first MG 11, enabling the locking gear 61 and the rotation limiter 62 to be fully engaged. This therefore prevents the hybrid vehicle 90 from accidentally rolling down the slope.

[0097] While the present embodiment of the present disclosure has been described, the present disclosure is not limited thereto. In other words, various modifications can be made within the scope of the present disclosure.

[0098] The hybrid vehicle control unit 50 includes the MG malfunction determination unit 52. If the MG malfunction determination unit 52 determines that one of the first and second MGs 11 and 12 is malfunctioning, the P-lock completion driver 53 performs the P-lock completion task using the other one that is operating properly. However, the present disclosure is not limited to the configuration of the hybrid vehicle control unit 50.

[0099] Specifically, the hybrid vehicle control unit 50 may select one of the first and second MGs 11 and 12 based on one of other parameters when determining that the P-lock operation of the P-lock mechanism 60 has not been completed. For example, the other parameters represent the operating conditions of the first and second MGs 11 and 12 when the hybrid vehicle 90 is parked, for example, the phase of the electrical rotation angle of each of the first and second MGs 11 and 12.

[0100] When the third control mode of the P-lock completion task is performed, which uses both the first and second MGs 11 and 12, the hybrid vehicle control unit 50 enables the P-lock completion task to be continuously executed even if there is a malfunction in one of the first and second MGs 11 and 12.

[0101] Hybrid vehicle control devices according to the present disclosure are not limited to those applied to hybrid vehicles each having a four-axis power transmission designed such that the output shaft of a first MG, the output shaft of an engine, the drive shaft, and the output shaft of a second MG are independently expressed on the power transmission alignment chart. Specifically, the hybrid vehicle control devices according to the present disclosure can be applied to hybrid vehicles having a one-way clutch. For example, the hybrid vehicle control devices according to the present disclosure can be applied to hybrid vehicles each having a three-axis power transmission designed such that the output shaft of the second MG and the drive shaft are shared with each other in the four-axis power transmission.

[0102] While the illustrated embodiment of the present disclosure has been described herein, the present disclosure is not limited to the embodiment described herein, but encompasses any and all embodiments with modifications, omissions, combinations (e.g., of aspects across different embodiments), adaptations, and / or alterations as appreciated by those skilled in the art based on the present disclosure. The limitations in the claims are to be interpreted broadly based on the language used in the claims and are not limited to examples described in the present specification or during the practice of the application, which are examples that are intended to be non-exclusive.

[0103] In a control device for a hybrid vehicle, a parking lock completion determination device determines whether a parking lock operation of a parking lock mechanism is completed. A parking lock completion driver performs a parking lock completion task, selectively driving at least one of the first and second motor generators to rotate the rotary shaft until the parking lock operation of the parking lock mechanism is completed. When the first motor generator is selected for the parking lock completion task, the parking lock driver causes the first motor generator to generate torque in the reverse rotation direction opposite to the forward rotation direction, and the torque in the reverse rotation direction rotates the drive shaft.

Claims

[1] Control device (50) for a hybrid vehicle (90), comprising: a machine (13) having an output shaft; a first motor generator (11) having a first output shaft; a second motor generator (12) having a second output shaft; a drive shaft (14) coupled to a drive wheel; a power transmission (100) that combines a power based on the output shaft of the engine (13), a power based on the first output shaft of the first motor generator (11), and a power based on the second output shaft of the second motor generator (12) and outputs the combined power to the drive wheel; a one-way clutch (16) which prevents reverse rotation of the output shaft of the engine (13); and a parking lock mechanism (60) comprising: a locking gear (61) designed to be rotated together with the drive gear, and a rotation limiter (62) which limits rotation of the drive shaft (14) when it is engaged with the locking gear (61), wherein the parking lock mechanism (60) is designed to perform a parking lock operation to engage the rotation limiter (62) with the locking gear (61) when a speed change position for the power transmission (100) is set to a parking position, the first output shaft of the first motor generator (11), the output shaft of the engine (13), the drive shaft (14) and the second output shaft of the second motor generator (12) are shown in this order in a nomogram of the power transmission (100); and a speed line representing relationships between the first output shaft of the first motor generator (11), the output shaft of the engine (13), the drive shaft (14) and the second output shaft of the second motor generator (12), in the nomogram is rotatable on the one-way clutch (16), wherein the control device (50) comprises: a parking lock completion determining means (51) configured to determine whether the parking lock operation of the parking lock mechanism (60) is completed, characterized by a parking lock completion driver (53) configured to, when it is determined by the parking lock completion determining means (51) that the parking lock operation of the parking lock mechanism (60) has not been completed, perform a parking lock completion task that selectively drives at least one of the first and second motor generators (11, 12) to rotate the drive shaft (14) until the parking lock operation of the parking lock mechanism (60) is completed; and a malfunction determining means (52) configured to determine whether at least one of the first and second motor generators (11, 12) has malfunctioned so as not to rotate in a commanded direction, wherein when a direction identical to a forward direction of the output shaft of the engine (13) is defined as a forward rotation direction, the parking lock completion driver (53) is designed to, when the first motor generator (11) is selected for the parking lock completion task, cause the first motor generator (11) to generate a torque in a reverse rotation direction opposite to the forward rotation direction, the torque in the reverse rotation direction rotating the drive shaft (14), and wherein, when it is determined by the malfunction determination means (52) that the first motor generator (11) is operating although an output of the first motor generator (11) deviates from a commanded value after it is determined by the parking lock completion determination means (51) that the parking lock operation of the parking lock mechanism (60) is incomplete while the hybrid vehicle (90) is parked, the parking lock completion driver (53) is configured to drive the first motor generator (11) to perform the parking lock completion task. [2] The control device (50) according to claim 1, wherein the parking lock completion driver (53) is configured to drive only the first motor generator (11) to operate when it is determined by the malfunction determining means (52) that at least the first motor generator (11) does not malfunction. [3] The control device (50) according to claim 1, wherein the parking lock completion driver (53) is configured to drive only the second motor generator (12) to operate when it is determined by the malfunction determining means (52) that at least the second motor generator (12) does not malfunction. [4] Control device (50) for a hybrid vehicle (90), comprising: a machine (13) having an output shaft; a first motor generator (11) having a first output shaft; a second motor generator (12) having a second output shaft; a drive shaft (14) coupled to a drive wheel; a power transmission (100) that combines a power based on the output shaft of the engine (13), a power based on the first output shaft of the first motor generator (11), and a power based on the second output shaft of the second motor generator (12) and outputs the combined power to the drive wheel; a one-way clutch (16) which prevents reverse rotation of the output shaft of the engine (13); and a parking lock mechanism (60) comprising: a locking gear (61) designed to be rotated together with the drive gear, and a rotation limiter (62) which limits rotation of the drive shaft (14) when it is engaged with the locking gear (61), wherein the parking lock mechanism (60) is designed to perform a parking lock operation to engage the rotation limiter (62) with the locking gear (61) when a speed change position for the power transmission (100) is set to a parking position, the first output shaft of the first motor generator (11), the output shaft of the engine (13), the drive shaft (14) and the second output shaft of the second motor generator (12) are shown in this order in a nomogram of the power transmission (100); and a speed line representing relationships between the first output shaft of the first motor generator (11), the output shaft of the engine (13), the drive shaft (14) and the second output shaft of the second motor generator (12), in the nomogram is rotatable on the one-way clutch (16), wherein the control device (50) comprises: a parking lock completion determining means (51) configured to determine whether the parking lock operation of the parking lock mechanism (60) is completed, characterized by a parking lock completion driver (53) configured to, when it is determined by the parking lock completion determining means (51) that the parking lock operation of the parking lock mechanism (60) has not been completed, perform a parking lock completion task that selectively drives at least one of the first and second motor generators (11, 12) to rotate the drive shaft (14) until the parking lock operation of the parking lock mechanism (60) is completed; and a malfunction determining means (52) configured to determine whether at least one of the first and second motor generators (11, 12) has malfunctioned so as not to rotate in a commanded direction, wherein when a direction identical to a forward rotation of the output shaft of the engine (13) is defined as a forward rotation direction, the parking lock completion driver (53) is designed to, when the second motor generator (12) is selected for the parking lock completion task, cause the second motor generator (12) to generate a torque in the forward rotation direction, the torque in the forward rotation direction rotating the drive shaft (14), and wherein, when it is determined by the malfunction determination means (52) that the second motor generator (12) is operating although an output of the second motor generator (12) deviates from a commanded value after it is determined by the parking lock completion determination means (51) that the parking lock operation of the parking lock mechanism (60) is incomplete while the hybrid vehicle (90) is parked, the parking lock completion driver (53) is configured to drive the second motor generator (12) to perform the parking lock completion task. [5] The control device (50) according to claim 4, wherein the parking lock completion driver (53) is configured to drive only the first motor generator (11) to perform the parking lock completion task when it is determined by the malfunction determining means (52) that at least the first motor generator (11) does not malfunction. [6] The control device (50) according to claim 4, wherein the parking lock completion driver (53) is configured to drive only the second motor generator (12) to perform the parking lock completion task when it is determined by the malfunction determining means (52) that at least the second motor generator (12) does not malfunction.

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