Control device

Abstract

To provide a control apparatus capable of suppressing a temperature rise of a rotary electric machine during a vehicle evacuation travel using the internal combustion engine.SOLUTION: In a vehicle comprising an internal combustion engine, a rotary electric machine to which output torque of the engine is input, a control system of the rotary electric machine, and a transmission for shifting rotation of the rotary electric machine, a control apparatus includes: detection means for detecting abnormality of the control system or communication with the control system; execution means for executing, in a case where the detection means detects the abnormality, an evacuation travel for causing the vehicle to travel using output torque of the engine; and shift means for upshifting the transmission in the case where a rotation speed of the rotary electric machine reaches or exceeds a threshold during the evacuation travel.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a control device. [Background technology]

[0002] In a hybrid vehicle equipped with an engine and a motor, if an abnormality occurs that prevents the motor from operating, the vehicle will perform evacuation driving using the output torque of the engine (see, for example, Patent Document 1). Examples of abnormalities that prevent the motor from operating include an abnormality in the control system, such as the ECU that controls the motor, or an abnormality in communication with the control system. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2017-226328 Summary of the Invention [Problem to be solved by the invention]

[0004] In a hybrid vehicle, where the engine output torque is transmitted to the transmission and drive wheels via a motor, the engine crankshaft and the motor drive shaft are engaged with each other via a clutch, so that the motor speed increases along with the engine speed during evacuation driving.

[0005] Therefore, if a one-phase short circuit occurs in the inverter that drives the motor during evacuation, excessive current may flow through the armature winding of the shorted phase, causing the motor to heat up and overheat. However, as described above, if an abnormality occurs that prevents the motor from operating, it may be difficult to detect a motor fault such as a one-phase short circuit, making it difficult to prevent the motor from heating up during evacuation.

[0006] The present invention has been made in view of the above-mentioned problems, and has an object to provide a control device that can suppress the temperature rise of a rotating electric machine during evacuation running of a vehicle using an internal combustion engine. [Means for solving the problem]

[0007] A control device of the present invention is a control device for a vehicle including an internal combustion engine, a rotating electric machine to which output torque of the internal combustion engine is input, a control system for the rotating electric machine, and a transmission that changes the rotation speed of the rotating electric machine, and includes: a detection means for detecting an abnormality in the control system or an abnormality in communication with the control system; an execution means for executing evacuation running that causes the vehicle to run using the output torque of the internal combustion engine when the detection means detects the abnormality; and a shifting means for upshifting the transmission when the rotation speed of the rotating electric machine becomes equal to or greater than a threshold value during the evacuation running. death , The execution means counts the number of times that the rotation speed of the rotating electric machine becomes equal to or greater than the threshold value during execution of the evacuation traveling, and stops the evacuation traveling in accordance with the number of times. .

[0008] In the above configuration, the shifting means may upshift the transmission by one stage when the rotation speed of the rotating electric machine becomes equal to or greater than the threshold value while the vehicle is performing the evacuation traveling.

[0010] In the above configuration, the execution unit increases the number of times after a predetermined time has elapsed since the rotation speed of the rotating electric machine became equal to or greater than the threshold value during the execution of the evacuation traveling. Let That's fine.

[0011] Another control device of the present invention is a control device for a vehicle including an internal combustion engine, a rotating electric machine to which output torque of the internal combustion engine is input, a control system for the rotating electric machine, and a transmission for changing the rotation speed of the rotating electric machine, the control device comprising: detection means for detecting an abnormality in the control system or an abnormality in communication with the control system; execution means for executing evacuation running in which the vehicle runs using the output torque of the internal combustion engine when the detection means detects the abnormality; and shifting means for upshifting the transmission when the rotation speed of the rotating electric machine becomes equal to or greater than a threshold value during the execution of the evacuation running, The execution means measures the time during which the rotation speed of the rotating electric machine becomes equal to or greater than the threshold value while the evacuation traveling is being performed, and stops the evacuation traveling in accordance with the time. do . [Effects of the Invention]

[0012] According to the present invention, it is possible to suppress a temperature rise of the rotating electric machine while the vehicle is running to evacuate using the internal combustion engine. [Brief explanation of the drawings]

[0013] [Figure 1] FIG. 1 is a configuration diagram illustrating an example of a hybrid vehicle system. [Figure 2] FIG. 1 is a configuration diagram illustrating an example of a vehicle control device. [Figure 3] FIG. 4 is a diagram showing changes in the rotation speed of the motor generator with respect to the vehicle speed for each gear position. [Figure 4] 4 is a flowchart illustrating an example of an operation of the vehicle control device. [Figure 5] 5 is a time chart showing an example of an operation of reducing the rotation speed of a motor generator by upshifting an automatic transmission. [Figure 6] 10 is a time chart showing an example of an operation in which the number of excesses reaches an upper limit number and the evacuation traveling is stopped. [Figure 7] 10 is a time chart showing an example of an operation in which the evacuation traveling is stopped when the excess time reaches the upper limit time. DETAILED DESCRIPTION OF THE INVENTION

[0014] (Hybrid vehicle system configuration) 1 is a configuration diagram showing an example of a hybrid vehicle system 9. The hybrid vehicle system 9 is mounted on, for example, a hybrid vehicle, and includes a vehicle control device 1, an engine 2, a clutch 3, a motor generator (MG) 4, an MG control device 6, an MG drive system 7, a torque converter (T / C) 52, an automatic transmission (A / T) 53, and drive wheels 54. The hybrid vehicle is an example of a vehicle.

[0015] The crankshaft 20 of the engine 2 is connected to the drive shaft 40 of the MG4 via the clutch 3. Therefore, while the engine 2 is starting, the output torque of the engine 2 is input to the MG4. The drive shaft of the MG4 is further connected to the input shaft 50 of the torque converter 52, and the input shaft 50 of the torque converter 52 is connected to the input shaft 51 of the automatic transmission 53. The output shaft 55 of the automatic transmission 53 is connected to the drive wheels 54 via a differential gear (not shown) or the like.

[0016] The automatic transmission 53 is an example of a transmission that changes the rotation of the MG 4. The automatic transmission 53 performs, for example, six-speed shifting under the control of the vehicle control device 1. The automatic transmission 53 changes the ratio of the rotation speed of the output shaft 55 to the rotation speed of the input shaft 51 according to the gear stages from first to sixth.

[0017] Engine 2 is an example of an internal combustion engine. Engine 2 compresses and ignites a mixture of gasoline and air supplied to a combustion chamber, causing pistons in cylinders to reciprocate, thereby rotating crankshaft 20. Clutch 3 switches crankshaft 20 and driveshaft 40 between an engaged state and a disengaged state. Clutch 3 engages or disengages clutch plates on the crankshaft 20 side and clutch plates on the driveshaft 40 side in response to hydraulic pressure controlled by a solenoid valve (not shown).

[0018] The MG drive system 7 also includes a battery 41, a system main relay (SMR) 42, and an inverter 45. The battery 41 is, for example, a lithium-ion battery, and supplies power to the MG 4. The SMR 42 is connected between the battery 41 and the inverter 45. The SMR 42 is turned on and off by the MG control device 6. When the SMR 42 is in the on state, power is supplied to the MG 4, and when the SMR 42 is in the off state, power is not supplied to the MG 4.

[0019] The inverter 45 converts the DC current of the battery 41 into a three-phase AC current by switching a plurality of switch elements and supplies the AC current to the MG 4. The MG control device performs switching control by outputting a switching signal such as a PWM (Pulse Width Modulation) signal to each switch element. The inverter 45 generates currents of u-phase, v-phase, and w-phase. Note that examples of switch elements include, but are not limited to, IGBTs (Insulated Gate Bipolar Transistors).

[0020] MG4 is an example of a rotating electric machine. MG4 functions as both a generator and a motor. When operating as a motor, MG4 is driven by three-phase AC current flowing from inverter 45 to three-phase windings. MG4 is equipped with a rotor and stator (not shown), and the rotor rotates due to a rotating magnetic field generated from the stator by the three-phase AC current. Drive shaft 40 is provided at the center of the rotor and rotates due to the rotation of the rotor.

[0021] The hybrid vehicle system 9 also has a crank angle sensor 21, a rotation speed sensor 47, and a current sensor 46. The crank angle sensor 21 detects the angle of the crankshaft 20 of the engine 2. The vehicle control device 1 obtains the detected value from the crank angle sensor 23 and uses it to control the engine 2.

[0022] The rotation speed sensor 47 detects the number of rotations per unit time (rotational speed) of the drive shaft 40 of the MG 4. The rotation speed sensor 47 may detect the rotation speed from a detection value (rotor position) of a resolver, for example. The vehicle control device 1 and the MG control device 6 acquire the detection value from the rotation speed sensor 47. The MG control device 6 performs switching control of the inverter 45 using the detection value of the rotation speed sensor 47. As will be described later, the vehicle control device 1 monitors the detection value of the rotation speed sensor 47 to suppress a rise in temperature of the MG 4 while the engine 2 is performing evacuation travel.

[0023] Current sensors 46 detect the respective current values ​​of the three-phase AC current output from inverter 45. MG control device 6 performs switching control of inverter 45 using the detected values ​​of current sensors 46. MG control device 6 also detects faults such as one-phase short circuit of MG 4 based on the detected values ​​of current sensors 46. If MG control device 6 detects a fault in MG 4, it executes fail-safe processing such as turning off SMR 42 or shutting down inverter 45.

[0024] The MG control device 6 is an example of a control system for the MG 4. The MG control device 6 is a computer such as an ECU (Electronic Control Unit) equipped with a processor and a memory. The MG control device 6 controls the drive of the MG drive system 7 by performing switching control of the inverter 45, etc. When the hybrid vehicle runs using the output torque of the MG 4 and the engine 2, the MG control device 6 communicates with the vehicle control device 1 to exchange various control information and control the drive of the MG drive system 7.

[0025] The hybrid vehicle system 9 also has an accelerator opening sensor 90, a brake opening sensor 91, a vehicle speed sensor 92, and a multi-information display (display) 93. The accelerator opening sensor 90 detects the opening of an accelerator pedal (not shown) of the hybrid vehicle and outputs it to the vehicle control device 1. The accelerator opening sensor 90 detects the opening of a brake pedal (not shown) of the hybrid vehicle and outputs it to the vehicle control device 1. The vehicle speed sensor 92 detects the traveling speed of the hybrid vehicle and outputs it to the vehicle control device 1.

[0026] The display 93 displays various information related to the state of the hybrid vehicle based on information signals input from the vehicle control device 1. For example, the display 93 displays Ready On, which indicates that the hybrid vehicle is ready to run, and Ready Off, which indicates that the hybrid vehicle is not ready to run.

[0027] The vehicle control device 1 is an example of a control device. The vehicle control device 1 includes various ECUs that control, for example, the engine 2, the clutch 3, and the automatic transmission 53. The vehicle control device 1 controls the operation of the hybrid vehicle in accordance with the detected values ​​of the accelerator opening sensor 90, the brake opening sensor 91, the vehicle speed sensor 92, the crank angle sensor 23, and the rotation speed sensor 47.

[0028] 2 is a configuration diagram showing an example of the vehicle control device 1. The vehicle control device 1 has a control unit 10, a storage unit 11, and a communication processing unit 12. The control unit 10 is an arithmetic circuit such as a CPU (Central Processing Unit), and the storage unit 11 is a memory such as a flash ROM (Read Only Memory). The communication processing unit 12 is a communication circuit for transmitting and receiving signals to and from the various sensors, the engine 2, and the automatic transmission 53. The control unit 10 can access the storage unit 11 and the communication processing unit 12.

[0029] The control unit 10 includes an operation control unit 100, an engine control unit 101, a gear shift control unit 102, and an abnormality detection unit 103. The operation control unit 100, the engine control unit 101, the gear shift control unit 102, and the abnormality detection unit 103 may be realized as separate ECUs or as a single ECU. The operation control unit 100 instructs the engine control unit 101, the gear shift control unit 102, and the abnormality detection unit 103 to operate in accordance with a predetermined sequence.

[0030] The engine control unit 101 controls the engine 2 based on the detection values ​​of various sensors in accordance with user operations. For example, the engine control unit 101 calculates a command value for the output torque of the engine 2 from an accelerator opening sensor 90, a brake opening sensor 91, and a vehicle speed sensor 92. The engine control unit 101 controls the intake amount and ignition timing of the engine 2 based on the detection value of the crank angle sensor 21 and the like in accordance with the command value.

[0031] The gear shift control unit 102 is an example of a gear shifting means of the automatic transmission 53. The gear shift control unit 102 appropriately switches the gear position of the automatic transmission 53 in accordance with instructions from the operation control unit 100 based on, for example, the detected values ​​of the accelerator opening sensor 90, the brake opening sensor 91, and the vehicle speed sensor 92.

[0032] The memory unit 11 stores gear map data 110. The gear map data 110 is characteristic data that indicates the correlation between the rotation speed of the crankshaft 20 and the drive shaft 40 and the vehicle speed for each gear. The gear change control unit 102 switches the gear based on the gear map data 110. The gear map data 110 is obtained in advance from the results of experiments or simulations and written to the memory unit 11.

[0033] The abnormality detection unit 103 is an example of a means for detecting an abnormality related to the MG control device 6. The abnormality detection unit 103 periodically monitors the operating state of the MG control device 6, for example, via the communication processing unit 12. The abnormality detection unit 103 detects an abnormality in the MG control device 6 or an abnormality in communication with the MG control device 6 based on the monitoring result.

[0034] The abnormality detection unit 103 can detect an abnormality in the MG control unit 6, for example, based on information in a status signal received from the MG control unit 6 via the communication processing unit 12. Furthermore, the abnormality detection unit 103 can detect an abnormality in communication with the MG control unit 6 if it cannot receive a status signal from the MG control unit 6 via the communication processing unit 12 for a certain period of time, or if it can receive a status signal but a predetermined number of errors occur. The abnormality detection unit 103 notifies the operation control unit 100 of the detection result of an abnormality related to the MG control unit 6 (hereinafter referred to as "MG control abnormality").

[0035] When the abnormality detection unit 103 detects an MG control abnormality, the engine control unit 101 executes evacuation running, causing the hybrid vehicle to run using the output torque of the engine 2. In other words, when an MG control abnormality occurs, the engine control unit 101 executes evacuation running for the vehicle using only the output torque of the engine 2, without using the output torque of the MG 4. The engine control unit 101 is an example of a means for executing evacuation running.

[0036] During evacuation travel, the engine control unit 101 is unable to detect a fault related to the MG 4, such as a one-phase short circuit in the inverter 45, from the MG control device 6 due to an MG control abnormality. If a one-phase short circuit fault occurs in the inverter 45, excessive current may flow through the winding of the shorted phase, causing the temperature of the MG 4 to rise and resulting in an overheating state.

[0037] Therefore, when the rotation speed of MG4 becomes equal to or exceeds a threshold value while the hybrid vehicle is running to avoid danger, the gear shift control unit 102 upshifts the automatic transmission 53. This reduces the rotation speed of MG4 (the rotation speed of the drive shaft 40), thereby suppressing an increase in the current flowing through the armature winding of MG4 due to the rotation of the drive shaft 40. This makes it possible to suppress a temperature rise in MG4 while the hybrid vehicle is running to avoid danger.

[0038] 3 is a diagram showing the change in rotation speed of the MG4 with respect to vehicle speed for each gear. In FIG. 3, the horizontal axis represents vehicle speed (km / h), and the vertical axis represents rotation speed of the MG4 (MG rotation speed) (rpm). The gears are assumed to be 1st to 6th gears. The rotation speed characteristics for each gear are stored as gear map data 110.

[0039] When the rotation speed becomes equal to or greater than the threshold value k, the gear shift control unit 102 upshifts the automatic transmission, thereby keeping the rotation speed below the threshold value k.

[0040] For example, assume that at the start of evacuation travel, the gear change control unit 102 controls the automatic transmission 53 at point Pa in fourth gear. At this time, if the user depresses the accelerator pedal to accelerate, the output torque of the engine 2 increases, causing the rotation speed to exceed the threshold k. As a result, the control point shifts from point Pa to point Pb, which is on the higher vehicle speed side.

[0041] When the rotation speed exceeds the threshold k, the gear shift control unit 102 upshifts the gear by one step from fourth to fifth. As a result, the rotation speed decreases and falls below the threshold k. At this time, the control point shifts from fourth-speed point Pb to fifth-speed point Pc.

[0042] If the user further depresses the accelerator pedal to accelerate, the output torque of the engine 2 increases, causing the rotation speed to exceed the threshold value k again. As a result, the control point shifts from point Pc to point Pd on the higher vehicle speed side.

[0043] When the rotation speed exceeds the threshold k, the gear shift control unit 102 upshifts the gear by one step from fifth gear to sixth gear. As a result, the rotation speed decreases and falls below the threshold k. At this time, the control point shifts from fifth gear point Pd to sixth gear point Pe.

[0044] In this way, when the rotation speed becomes equal to or exceeds threshold value k during evacuation traveling, gear shift control unit 102 upshifts automatic transmission 53 by one gear. As a result, even if the vehicle speed increases and the rotation speed increases, the rotation speed can be kept below threshold value k by switching the gear, and because the gear is upshifted by only one gear, vibrations generated in the vehicle body can be suppressed more than when the gear is upshifted by multiple gears. However, gear shift control unit 102 is not limited to this, and may also upshift automatic transmission 53 by multiple gears when the rotation speed becomes equal to or exceeds threshold value k.

[0045] Furthermore, if the rotation speed does not decrease due to an upshift of the automatic transmission 53, the engine control unit 101 stops the evacuation traveling and puts the hybrid vehicle into a Ready-off state. For example, the engine control unit 101 counts the number of times the rotation speed has exceeded a threshold k (hereinafter referred to as the "excess number of times") and measures the time during which the rotation speed has exceeded the threshold k (hereinafter referred to as the "excess time") using a timer. The excess time is the time from when the rotation speed has exceeded the threshold k during evacuation traveling to when the rotation speed falls below the threshold k. The engine control unit 101 stops the evacuation traveling when the excess number of times exceeds a predetermined number or when the excess time exceeds a predetermined time. This suppresses a rise in temperature of the MG4 that would otherwise occur if the evacuation traveling is continued while the rotation speed exceeds the threshold k.

[0046] (Vehicle control device operation) 4 is a flowchart showing an example of the operation of the vehicle control device 1. This operation is executed after the engine 2 and the MG 4 are started.

[0047] First, the engine control unit 101 executes normal driving of the hybrid vehicle (step St1). At this time, the engine control unit 101 allocates the output torque required in response to the user's accelerator operation as a command value to the engine 2 and the MG 4. The engine control unit 101 notifies the MG control device 6 of the command value of the output torque of the MG 4, and drives the engine 2 in accordance with the command value of the output torque of the engine 2. The MG control device 6 performs switching control of the inverter 45 in accordance with the command value of the output torque of the MG 4. In this way, during normal driving, the engine control unit 101 drives the hybrid vehicle using the output torque of the engine 2 and the MG 4.

[0048] Next, the abnormality detection unit 103 determines whether or not there is an MG control abnormality (step St2). If the abnormality detection unit 103 determines that there is no MG control device 6 (No in step St2), the process of step St1 is executed again.

[0049] If the abnormality detection unit 103 determines that the MG control device 6 is present (Yes in step St2), the engine control unit 101 executes evacuation running of the hybrid vehicle (step St3). At this time, due to the MG control abnormality, the engine control unit 101 does not distribute output torque to the MG 4, but causes the engine 2 to output all of the required output torque. The engine 2 is driven according to the command value for the output torque of the engine 2. In this way, during evacuation running, the engine control unit 101 causes the hybrid vehicle to run using only the output torque of the engine 2.

[0050] Next, the gear shift control unit 102 acquires the rotation speed Nm of the drive shaft 40 of the MG 4 from the rotation speed sensor 47 (step St4). Next, the gear shift control unit 102 compares the rotation speed Nm with a threshold value k (step St5). If the rotation speed Nm is less than the threshold value k (No in step St5), the processing from step St3 onwards is executed again.

[0051] If the rotation speed Nm is equal to or greater than the threshold value k (Yes in step St5), the gear shift control unit 102 upshifts the automatic transmission (step St6). As a result, as described above, the rotation speed according to the vehicle speed of the hybrid vehicle decreases so as to follow the characteristics of a higher gear.

[0052] Next, the engine control unit 101 starts a timer for monitoring the overtime and the number of overtimes (step St7). The timer may be realized by either hardware or software. The timer value measured by the timer corresponds to the overtime. The initial values ​​of the overtime and the number of overtimes are both 0.

[0053] Next, the engine control unit 101 compares the timer value with a predetermined value Tn (step St8). If the timer value is equal to or less than the predetermined value Tn (No in step St8), the processes of steps St9 to St11, which will be described later, are not executed.

[0054] If the timer value is greater than the predetermined value Tn (Yes in step St8), the engine control unit 101 adds 1 to the number of excesses (step St9). In this way, while the hybrid vehicle is performing evacuation running, the engine control unit 101 increases the number of excesses after the predetermined time (Tn) has elapsed since the rotation speed Nm of the drive shaft 40 became equal to or greater than the threshold value k. Therefore, if the rotation speed Nm repeatedly increases and decreases near the threshold value k due to, for example, an error in the rotation speed sensor, the number of excesses is prevented from being erroneously increased too much. This makes it possible to count the number of excesses with high accuracy.

[0055] Next, the engine control unit 101 compares the number of times of exceedance with the upper limit number Nmax (step St10). The upper limit number Nmax is the upper limit of the number of times of exceedance, and is set in advance based on the electrical characteristics of the MG 4 and the inverter 45, for example.

[0056] When the number of excesses reaches the upper limit number Nmax (Yes in step St10), the engine control unit 101 determines that it is difficult to suppress the temperature rise of the MG4 due to upshifting, and executes the Ready-off process (step St14). At this time, the engine control unit 101 displays a Ready-off state, which means that the hybrid vehicle cannot be driven, on the display 93. This notifies the user that the hybrid vehicle will be stopped.

[0057] Next, the engine control unit 101 stops the evacuation running of the hybrid vehicle (step St15). At this time, the engine control unit 101 stops the operation of the engine 2 according to a predetermined pattern. This makes it possible to suppress the temperature rise of the MG4 even when it is difficult to suppress an increase in the rotation speed Nm due to an upshift of the automatic transmission 53.

[0058] Furthermore, if the number of overruns is less than the upper limit number of overruns Nmax (No in step St10), the engine control unit 101 compares the timer value with an upper limit time Tm (step St11). The upper limit time Tm is the upper limit of the timer value, which is the overrun time, and is set in advance based on, for example, the electrical characteristics of the MG 4 and the inverter 45.

[0059] If the excess time reaches the upper limit time (Yes in step St11), the engine control unit 101 determines that it is difficult to suppress the temperature rise of the MG4 due to the upshift, and executes Ready-off processing (step St14). Next, the engine control unit 101 stops the evacuation running of the hybrid vehicle (step St15).

[0060] If the excess time is less than the upper limit time (No in step St11), the engine control unit 101 acquires the rotation speed Nm of the drive shaft 40 of the MG4 from the rotation speed sensor 47 (step St12). Next, the engine control unit 101 compares the rotation speed Nm with a threshold value k (step St13). If the rotation speed Nm is equal to or greater than the threshold value k (No in step St13), the rotation speed Nm has not decreased, so the processes from step St11 onwards are executed again.

[0061] Furthermore, if the rotation speed Nm is less than the threshold value k (Yes in step St13), the engine control unit 101 determines that the rotation speed Nm has decreased due to the upshift, and executes evacuation running again (step St3). After that, the processes from step St4 onwards are executed again.

[0062] In this way, the engine control unit 101 counts the number of times that the rotation speed Nm of the drive shaft 40 exceeds the threshold value k while the evacuation traveling is being performed, and stops the evacuation traveling in accordance with the number of times exceeded. Also, the engine control unit 101 counts the time (timer value) during which the rotation speed Nm of the drive shaft 40 exceeds the threshold value k while the evacuation traveling is being performed, and stops the evacuation traveling in accordance with the time exceeded.

[0063] Therefore, if the rotation speed Nm does not decrease below the threshold value k even when the transmission control unit 102 upshifts the automatic transmission 53, the engine control unit 101 can stop the evacuation driving, thereby decreasing the rotation speed Nm of the drive shaft 40 and suppressing the temperature rise of the MG4.

[0064] (Example of vehicle control device operation) Next, an example of the operation of the vehicle control device 1 will be described with reference to Figures 5 to 7. Figures 5 to 7 show time changes in the rotation speed Nm of MG4 (drive shaft 40), driving mode, excess flag, number of excesses, gear position, and driving availability state. Here, the driving mode includes normal driving, in which driving is performed using the output torque of engine 2 and MG4, as described above, and evacuation driving, in which driving is performed using only the output torque of engine 2.

[0065] The excess flag is a flag that triggers counting the number of times the excess has occurred, and when it changes from "0" to "1", 1 is added to the excess number of times. The driving possibility state can be Ready On, which indicates a driving possible state, or Ready Off, which indicates a driving impossible state. In this example, it is assumed that the upper limit number of times Nmax is set to 2 times.

[0066] 5 is a time chart showing an example of an operation for reducing the rotation speed of MG 4 by upshifting automatic transmission 53. At time T1, engine control unit 101 switches the driving mode from normal driving to evacuation driving when abnormality detection unit 103 detects an MG control abnormality. The rotation speed of MG 4 exceeds threshold k at time T0 during normal driving, and remains equal to or greater than threshold k at time T1.

[0067] Assume that the automatic transmission 53 is initially in fourth gear. At time T1 when the driving mode is switched to evacuation driving, the rotation speed of the MG4 is equal to or greater than threshold k, so the gear shift control unit 102 upshifts the automatic transmission 53 from fourth gear to fifth gear. As a result, the rotation speed of the MG4 starts to decrease and falls below threshold k at time T3. This makes it possible to suppress a rise in temperature of the MG4 even if a one-phase short circuit occurs in the inverter 45.

[0068] Furthermore, the engine control unit 101 monitors the excess time using a timer during evacuation running. When the excess time exceeds a predetermined value Tn at time T2, the engine control unit 101 updates the excess flag from "0" to "1." The engine control unit 101 adds 1 to the excess count, triggered by the change in the excess flag. The engine control unit 101 updates the excess flag from "1" to "0" at time T3 when the rotation speed becomes less than the threshold k.

[0069] In this example, the number of times exceeding the limit is less than the upper limit number Nmax (=2), and the time period exceeding the limit is less than the upper limit time Tm. Therefore, the engine control unit 101 can maintain Ready On even during evacuation travel.

[0070] 6 is a time chart showing an example of the operation of stopping the evacuation traveling when the excess number of times reaches the upper limit number of times Nmax. In FIG. 6, the explanation of the operation from time T0 to time T3 that is common to FIG. 5 will be omitted.

[0071] After the rotation speed of MG4 falls below threshold k at time T3, it again becomes equal to or greater than threshold k at time T10. In response to this, gear change control unit 102 upshifts automatic transmission 53 from fifth gear to sixth gear. As a result, the rotation speed of MG4 starts to decrease and falls below threshold k at time T12.

[0072] Furthermore, when the excess time exceeds a predetermined value Tn at time T11, the engine control unit 101 updates the excess flag from "0" to "1." The engine control unit 101 adds 1 to the excess count, triggered by the change in the excess flag. As a result, the excess count reaches the upper limit count Nmax (=2). The engine control unit 101 updates the excess flag from "1" to "0" at time T12 when the rotation speed becomes less than the threshold k.

[0073] When the number of excesses reaches the upper limit number Nmax, the engine control unit 101 sets the driving enable / disable state to Ready Off. The engine control unit 101 also stops evacuation driving. In this way, when the number of excesses reaches the upper limit number even when the automatic transmission 53 is upshifted, the vehicle control device 1 determines that it is difficult to suppress the temperature rise of the MG4 due to the upshift, and stops the engine 2 to reduce the rotation speed and suppress the temperature rise of the MG4.

[0074] 7 is a time chart showing an example of the operation of stopping the evacuation traveling when the excess time reaches the upper limit time Tm. In FIG. 7, the explanation of the operation from time T0 to T2, which is common to FIG.

[0075] The rotation speed of MG4 decreases after the automatic transmission 53 is upshifted, but the rate of decrease with time is small, so the excess time exceeds the upper limit time Tm at time T20. Because the excess time exceeds the upper limit time Tm at time T20, the engine control unit 101 sets the driving enable / disable state to Ready Off. In addition, the engine control unit 101 stops evacuation driving.

[0076] In this way, when the excess time reaches the upper limit time Tm even when the automatic transmission 53 is upshifted, the vehicle control device 1 determines that it is difficult to suppress the temperature rise of the MG4 due to the upshift, and stops the engine 2 to reduce the rotation speed and suppress the temperature rise of the MG4.

[0077] In this embodiment, the vehicle control device 1 stops the evacuation driving based on the results of monitoring both the number of times exceeded and the excess time, but it may also stop the evacuation driving based on the results of monitoring only one of the number of times exceeded and the excess time.

[0078] The above-described embodiment is a preferred example of the present invention, but the present invention is not limited to this and can be modified in various ways without departing from the spirit of the present invention. [Explanation of symbols]

[0079] 1 Vehicle control device (control device) 2. Engine (internal combustion engine) 4 Motor generator (rotating electric machine) 6 MG control device (control system) 53 Automatic transmission (transmission) 101 Engine control unit (execution means) 102 Shift control unit (shift means) 103 Abnormality detection unit (detection means)

Claims

1. A control device for a vehicle including an internal combustion engine, a rotating electric machine to which an output torque of the internal combustion engine is input, a control system for the rotating electric machine, and a transmission that changes the rotation speed of the rotating electric machine, a detection means for detecting an abnormality in the control system or an abnormality in communication with the control system; an execution means for executing evacuation running by causing the vehicle to run using the output torque of the internal combustion engine when the detection means detects the abnormality; a speed change unit that upshifts the transmission when a rotation speed of the rotating electric machine becomes equal to or greater than a threshold value during the execution of the evacuation traveling; the execution means counts the number of times that the rotation speed of the rotating electric machine becomes equal to or greater than the threshold value during execution of the evacuation traveling, and stops the evacuation traveling in accordance with the number of times. Control device.

2. the execution unit increases the number of times after a predetermined time has elapsed since the rotation speed of the rotating electric machine became equal to or greater than the threshold value during the execution of the evacuation traveling. The control device according to claim 1 .

3. A control device for a vehicle including an internal combustion engine, a rotating electric machine to which an output torque of the internal combustion engine is input, a control system for the rotating electric machine, and a transmission that changes the rotation speed of the rotating electric machine, a detection means for detecting an abnormality in the control system or an abnormality in communication with the control system; an execution means for executing evacuation running by causing the vehicle to run using the output torque of the internal combustion engine when the detection means detects the abnormality; a speed change unit that upshifts the transmission when a rotation speed of the rotating electric machine becomes equal to or greater than a threshold value during the execution of the evacuation traveling; the execution means measures a time during which the rotation speed of the rotating electric machine becomes equal to or greater than the threshold value while the evacuation traveling is being performed, and stops the evacuation traveling in accordance with the time. Control device.

4. the shifting means upshifts the transmission by one stage when the rotation speed of the rotating electric machine becomes equal to or greater than the threshold value during the execution of the evacuation traveling.

4. The control device according to claim 1.

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