JP7243420B2 - vehicle - Google Patents

Description

TECHNICAL FIELD The present disclosure relates to vehicles and, more particularly, to controlling engine output in vehicles.

Japanese Patent Laying-Open No. 2015-58924 (Patent Document 1) discloses a hybrid vehicle including a turbocharger.

JP 2015-58924 A

Incidentally, if an abnormality occurs in the supercharger during execution of supercharging and the supercharging cannot be stopped, the controllability of the engine torque deteriorates due to the continuation of the supercharging. Then, the engine torque tends to become excessive due to the inability of the control device to sufficiently control the engine torque. If the engine torque becomes excessively large, the in-vehicle equipment connected to the engine may be damaged.

The present disclosure has been made to solve the above problems, and its purpose is to suppress an excessive increase in engine torque when an abnormality occurs in the supercharger and supercharging cannot be stopped. It is to provide a vehicle that can

A vehicle according to the present disclosure includes drive wheels, a drive device that drives the drive wheels, and a control device that is configured to control the drive device. The drive includes an engine. An engine includes an engine body that performs combustion, an intake passage and an exhaust passage connected to the engine body, a supercharger, a bypass passage connected to the exhaust passage, and a waste gate valve (hereinafter referred to as a waste gate valve) provided in the bypass passage. (also referred to as "WGV"). The turbocharger includes a compressor provided in an intake passage and a turbine provided in an exhaust passage. The bypass passage is configured to channel the exhaust around the turbine. When the WGV is stuck at the opening degree during supercharging (hereinafter also referred to as "when the WGV is stuck closed"), the control device controls the drive device so that the WGV is not stuck. (hereinafter also referred to as "when WGV is normal").

When the WGV closes, more exhaust flow enters the turbine. The turbine is driven by the exhaust flow, turning the compressor to supercharge the engine. Therefore, the WGV is closed when supercharging the engine. If the WGV is stuck at the opening during supercharging, supercharging is continued.

When the WGV is stuck closed (that is, when supercharging cannot be stopped), the above control device controls the fluctuation of the engine power more than when the WGV is normal (that is, when supercharging can be stopped). controls the drive of By suppressing fluctuations in engine power, the control device described above can easily control the engine torque. This suppresses an excessive increase in engine torque. Therefore, according to the vehicle described above, it is possible to prevent the engine torque from becoming excessively large when an abnormality occurs in the supercharger and supercharging cannot be stopped.

The above control device determines the required engine power (that is, the power required of the engine) based on the amount of accelerator operation by the driver, and controls the engine so that the power output from the engine becomes the required engine power. It may be configured as The control device is configured to determine a target rotation speed and a target torque of the engine based on the required engine power, and control the engine so that the rotation speed and the torque of the engine become the target rotation speed and the target torque, respectively. may

The drive device described above may further include a continuously variable transmission mechanism. The continuously variable transmission mechanism has a first rotating element and a second rotating element, and is configured to be able to continuously change the ratio of the rotating speed of the first rotating element to the rotating speed of the second rotating element. The first rotating element of the continuously variable transmission may be driven by the engine, and power output from the second rotating element of the continuously variable transmission may be transmitted to drive wheels of the vehicle. With such a configuration, the above ratio (and thus the gear ratio between the engine and the drive wheels) can be changed continuously, so that the rotational speed of the engine can be controlled with a high degree of freedom. Therefore, according to the above configuration, it becomes easier to control the engine operating point in accordance with the required engine power.

The above-described continuously variable transmission mechanism may include a planetary gear having a third rotating element in addition to the above-described first rotating element and second rotating element. The above drive device may further include a first motor generator mechanically connected to the third rotating element of the planetary gear, and a second motor generator mechanically connected to the driving wheel. With such a configuration, the torque of the driving wheels can be adjusted by the second motor generator, so it is possible to control the torque of the engine with a high degree of freedom. Therefore, according to the above configuration, it becomes easier to control the engine operating point in accordance with the required engine power. Also, it is possible to generate power by the first motor generator and the second motor generator.

As described above, in the configuration in which the engine and the first motor generator are connected via the planetary gear, the excessive increase in engine torque causes the first motor generator to rotate at an excessive rotational speed (hereinafter referred to as " (also referred to as "over-rotation") can occur. However, the control device described above can suppress the engine torque from becoming excessive by the above-described engine power control (that is, control for suppressing fluctuations in engine power when the WGV is stuck closed). Therefore, in the above vehicle, excessive rotation of the first motor generator is suppressed.

When the WGV is stuck at the opening during supercharging during acceleration of the vehicle, the control device described above increases the power output from the engine more gently than when the WGV is not stuck. can be

As described above, by making the increase in engine power when the WGV is stuck closed slower than when the WGV is normal, the increase in engine power when the WGV is stuck closed can be suppressed. The control device may moderate the increase in engine power when the WGV is stuck closed by correcting the required engine power when the WGV is stuck closed. In addition, as described below, the control device may moderate the increase in engine power when the WGV is stuck closed by using an upper limit value for the rate of increase in engine power.

The above control device may be configured to control the drive device so that the amount of increase in the power output from the engine per unit time (hereinafter also referred to as "increase rate") is equal to or less than the upper limit value. The upper limit value when the WGV is stuck closed may be smaller than the upper limit value when the WGV is normal.

As described above, by changing the upper limit of the engine power increase rate, it is possible to adjust the ease with which the engine power increases. Since the engine power does not increase at a speed exceeding the upper limit of the increase rate, the smaller the upper limit of the increase rate, the more difficult it is to increase the engine power. By setting the upper limit value of the increase rate of the engine power when the WGV is stuck closed to be smaller than when the WGV is normal, the increase of the engine power when the WGV is stuck closed is suppressed more than when the WGV is normal.

The control device described above may be configured to cause the vehicle to run in evacuation mode when the WGV is stuck at the opening degree during execution of supercharging. In such a configuration, the controllability of the engine torque can be improved by suppressing fluctuations in the engine power when the WGV is stuck closed (that is, during the evasive running of the vehicle). By improving the controllability of the engine torque while the vehicle is in the evacuation mode, it is possible to prevent the engine torque from becoming excessively large. Also, the control device can easily control the rotation speed of the engine to a desired rotation speed while the vehicle is in the evacuation mode. Evacuation driving is driving for moving the vehicle to a safe place when an abnormality occurs while the vehicle is driving. For example, the vehicle may be evacuated to the side of the road by evacuating.

The vehicle described above may further include a WGV actuator that drives the WGV. When the torque of the engine exceeds a threshold (hereinafter also referred to as "threshold Th"), the control device commands the WGV actuator to close the WGV to the degree of opening during supercharging (hereinafter referred to as "close command ), and issues a command to the WGV actuator to open the WGV (hereinafter also referred to as an “open command”) when the engine torque falls below the threshold value Th. In such a configuration, execution/stop of supercharging can be switched depending on the magnitude of torque. That is, supercharging is performed when the WGV actuator closes the WGV in accordance with a close command from the control device, and supercharging stops when the WGV actuator opens the WGV in accordance with an open command from the control device.

The vehicle described above may further include at least one of a boost pressure sensor that detects the boost pressure of the engine and an air flow meter that detects the intake flow rate of the engine. The above-described control device uses the behavior of at least one of the boost pressure and the intake flow rate when an open command is issued to the WGV actuator to determine whether the WGV is stuck at the opening degree during supercharging. It may be configured as

As the opening of the WGV increases, the intake flow rate of the engine decreases and the boost pressure of the engine decreases. For this reason, the control device diagnoses whether or not the WGV operates as instructed by confirming how at least one of the boost pressure and the intake air flow rate changes when an instruction is given to the WGV actuator. can be done. According to the above configuration, the control device can obtain the result of the WGV fixation diagnosis using the detection value of the sensor.

As each of the supercharging pressure sensor and the airflow meter, for example, sensors used in vehicle engine control can be used. However, the present invention is not limited to this, and each of the boost pressure sensor and the airflow meter may be sensors for diagnosis provided at positions where data used for diagnosis can be obtained with high sensitivity.

The WGV actuators described above may be configured to utilize negative pressure to drive the WGV. Negative pressure WGVs tend to be more prone to sticking than electric WGVs. The WGV actuator described above may include a negative pressure pump that generates negative pressure. The negative pressure pump may be a mechanical pump driven by the engine, or an electric pump.

The degree of opening during execution of supercharging may be a fully closed degree of opening. Since the opening degree at the time of execution of supercharging is the fully closed opening degree, it becomes easy to obtain a large engine power by supercharging. Moreover, the opening degree at the time of stopping the supercharging may be the full opening degree. Since the degree of opening at the time of stopping supercharging is the full-open degree, it becomes easier to suppress deterioration in fuel consumption due to supercharging. Note that the fully closed opening degree of the WGV means the opening degree at which the WGV blocks the flow of the exhaust gas in the bypass passage. The full opening of the WGV means the maximum opening of the WGV (that is, the maximum opening of the WGV).

According to the present disclosure, it is possible to provide a vehicle capable of suppressing an excessive increase in engine torque when an abnormality occurs in the supercharger and supercharging cannot be stopped.

1 is a diagram showing a vehicle drive system according to an embodiment of the present disclosure; FIG. 1 is a diagram showing a vehicle engine according to an embodiment of the present disclosure; FIG. 1 is a diagram showing a vehicle control system according to an embodiment of the present disclosure; FIG. FIG. 4 is a collinear diagram showing an example of the relationship between rotational speeds of rotating elements (sun gear, carrier, ring gear) of planetary gears during HV running in the vehicle according to the embodiment of the present disclosure; FIG. 4 is a nomographic diagram showing an example of the relationship between rotational speeds of rotating elements (sun gear, carrier, ring gear) of planetary gears during EV running in the vehicle according to the embodiment of the present disclosure; FIG. 4 is a nomographic chart showing an example of the relationship between rotational speeds of rotating elements (sun gear, carrier, ring gear) of planetary gears while the vehicle is stopped in the vehicle according to the embodiment of the present disclosure; 1 is a functional block diagram showing components of a vehicle control device according to an embodiment of the present disclosure by function; FIG. 4 is a flow chart showing a procedure for determining a control amount of a vehicle drive system according to an embodiment of the present disclosure; FIG. 4 is a diagram showing an example of a recommended action line used in vehicle engine control according to the embodiment of the present disclosure; FIG. 4 is a flow chart showing a processing procedure of supercharging control according to the embodiment of the present disclosure; FIG. 4 is a diagram for explaining evacuation control according to the embodiment of the present disclosure; FIG. FIG. 4 is a diagram for explaining over-rotation of the first motor generator; FIG. 4 is a flow chart showing a processing procedure of WGV closed stuck diagnosis executed by the vehicle control device according to the embodiment of the present disclosure;

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and the description thereof will not be repeated. Hereinafter, the electronic control unit is also referred to as "ECU". Moreover, a hybrid vehicle (Hybrid Vehicle) is also called "HV" and an electric vehicle (Electric Vehicle) is also called "EV."

FIG. 1 is a diagram showing a vehicle drive system according to this embodiment. In this embodiment, a front-wheel-drive four-wheeled vehicle (more specifically, a hybrid vehicle) is assumed, but the number of wheels and drive system can be changed as appropriate. For example, the drive system may be four-wheel drive.

Referring to FIG. 1, a vehicle drive device 10 includes an engine 13 and MGs (Motor Generators) 14 and 15 as power sources for running. Each of the MGs 14 and 15 is a motor generator that has both a function as a motor that outputs torque when supplied with drive power and a function as a generator that generates generated power when torque is applied. . AC motors (for example, permanent magnet synchronous motors or induction motors) are used as each of MGs 14 and 15 . MG 14 is electrically connected to battery 18 via an electric circuit including first inverter 16 . MG 15 is electrically connected to battery 18 via an electric circuit including second inverter 17 . The first inverter 16 and the second inverter 17 are included in a PCU 19 (see FIG. 3) which will be described later. MGs 14, 15 have rotor shafts 23, 30, respectively. The rotor shafts 23, 30 correspond to the rotation shafts of the MGs 14, 15, respectively. MG14 and MG15 according to this embodiment correspond to examples of a "first motor generator (MG1)" and a "second motor generator (MG2)" according to the present disclosure, respectively.

Battery 18 includes, for example, a secondary battery. A lithium ion battery, for example, can be used as the secondary battery. The battery 18 may include an assembled battery composed of a plurality of electrically connected secondary batteries (for example, lithium ion batteries). In addition, the secondary battery that constitutes the battery 18 is not limited to the lithium ion battery, and may be another secondary battery (for example, a nickel metal hydride battery). As the battery 18, an electrolyte secondary battery may be adopted, or an all-solid secondary battery may be adopted. Any storage device can be used as the battery 18, and a large-capacity capacitor or the like can also be used.

Drive device 10 includes a planetary gear mechanism 20 . Engine 13 and MG 14 are connected to planetary gear mechanism 20 . The planetary gear mechanism 20 is a single pinion type planetary gear, and is arranged on the same axis line Cnt as the output shaft 22 of the engine 13 .

The planetary gear mechanism 20 has a sun gear S, a ring gear R arranged coaxially with the sun gear S, a pinion gear P meshing with the sun gear S and the ring gear R, and a carrier C holding the pinion gear P so that it can rotate and revolve. Each of the engine 13 and MG 14 is mechanically connected to drive wheels 24 via a planetary gear mechanism 20 . An output shaft 22 of the engine 13 is connected to the carrier C. As shown in FIG. A rotor shaft 23 of the MG 14 is connected to the sun gear S. Ring gear R is connected to output gear 21 .

The planetary gear mechanism 20 has three rotating elements, namely an input element, an output element and a reaction force element. In the planetary gear mechanism 20, the carrier C is an input element, the ring gear R is an output element, and the sun gear S is a reaction force element. The carrier C, ring gear R, and sun gear S according to this embodiment respectively correspond to examples of the "first rotating element", "second rotating element", and "third rotating element" according to the present disclosure.

Torque output from the engine 13 is input to the carrier C. As shown in FIG. The planetary gear mechanism 20 is configured to divide and transmit the torque output from the engine 13 to the output shaft 22 to the sun gear S (and thus the MG 14) and the ring gear R (and thus the output gear 21). The ring gear R outputs torque to the output gear 21, and the sun gear S receives reaction torque from the MG14. The power output from the planetary gear mechanism 20 (planetary gear) (that is, the power output to the output gear 21) is driven by a driven gear 26, a counter shaft 25, a drive gear 27, a differential gear 28, and a drive shaft 32, which will be described below. 33 to drive wheels 24 .

The drive device 10 further comprises a countershaft 25, a driven gear 26, a drive gear 27, a differential gear 28, a drive gear 31 and drive shafts 32,33. The differential gear 28 corresponds to a final reduction gear and includes a ring gear 29 .

The planetary gear mechanism 20 and the MG 15 are configured such that the power output from the planetary gear mechanism 20 and the power output from the MG 15 are combined and transmitted to the driving wheels 24 . Specifically, the output gear 21 connected to the ring gear R of the planetary gear mechanism 20 meshes with the driven gear 26 . A drive gear 31 attached to the rotor shaft 30 of the MG 15 also meshes with the driven gear 26 . The countershaft 25 is attached to the driven gear 26 and arranged parallel to the axis Cnt. The drive gear 27 is attached to the countershaft 25 and meshes with the ring gear 29 of the differential gear 28 . Driven gear 26 acts to combine torque output from MG 15 to rotor shaft 30 and torque output from ring gear R to output gear 21 . The drive torque thus synthesized is transmitted to the drive wheels 24 via drive shafts 32 and 33 extending left and right from the differential gear 28 .

The drive device 10 further comprises a mechanical oil pump 36 and an electric oil pump 38 . The oil pump 36 is provided coaxially with the output shaft 22 . Oil pump 36 is driven by engine 13 . Oil pump 36 delivers lubricating oil to planetary gear mechanism 20, MG14, MG15, and differential gear 28 when engine 13 is operating. The electric oil pump 38 is driven by power supplied from the battery 18 or another vehicle-mounted battery (for example, an auxiliary battery) (not shown), and controlled by an HVECU 62 (see FIG. 3), which will be described later. The electric oil pump 38 sends lubricating oil to the planetary gear mechanism 20, MG14, MG15, and the differential gear 28 when the engine 13 is stopped. Lubricating oil delivered by each of oil pump 36 and electric oil pump 38 has a cooling function.

FIG. 2 is a diagram showing the configuration of the engine 13. As shown in FIG. Referring to FIG. 2, engine 13 is, for example, an in-line four-cylinder spark ignition internal combustion engine. The engine 13 has an engine body 13a including four cylinders 40a, 40b, 40c and 40d. In the engine body 13a, four cylinders 40a, 40b, 40c and 40d are arranged in one direction. Hereinafter, each of the cylinders 40a, 40b, 40c, and 40d will be referred to as "cylinder 40" unless otherwise specified.

An intake passage 41 and an exhaust passage 42 are connected to each cylinder 40 of the engine body 13a. The intake passage 41 is opened and closed by two intake valves 43 provided for each cylinder 40 , and the exhaust passage 42 is opened and closed by two exhaust valves 44 provided for each cylinder 40 . By adding fuel (for example, gasoline) to the air supplied to the engine body 13a through the intake passage 41, a mixture of air and fuel is generated. Fuel is injected into the cylinder 40 by an injector 46 provided for each cylinder 40 , for example, and an air-fuel mixture is generated within the cylinder 40 . A spark plug 45 provided for each cylinder 40 ignites the air-fuel mixture in the cylinder 40 . Thus, combustion is performed in each cylinder 40 . Combustion energy generated when the air-fuel mixture is combusted in each cylinder 40 is converted into kinetic energy by a piston (not shown) in each cylinder 40 and output to the output shaft 22 (FIG. 1). The fuel supply method is not limited to the in-cylinder injection, and may be port injection or a combination of in-cylinder injection and port injection.

The engine 13 includes a turbocharger 47 that supercharges intake air using exhaust energy. The supercharger 47 is a turbocharger that includes a compressor 48, a turbine 53, and a shaft 53a. The compressor 48 and the turbine 53 are configured to be connected to each other via a shaft 53a and rotate integrally. The rotational force of the turbine 53 that rotates in response to the exhaust flow discharged from the engine body 13a is transmitted to the compressor 48 via the shaft 53a. The rotation of the compressor 48 compresses intake air directed toward the engine body 13a, and the compressed air is supplied to the engine body 13a. The supercharger 47 is configured to supercharge the intake air (that is, increase the density of the air taken into the engine body 13a) by rotating the turbine 53 and the compressor 48 using exhaust energy. be done.

The compressor 48 is arranged in the intake passage 41 . An air flow meter 50 is provided upstream of the compressor 48 in the intake passage 41 . The airflow meter 50 is configured to output a signal corresponding to the flow rate of air flowing through the intake passage 41 . An intercooler 51 is provided at a position downstream of the compressor 48 in the intake passage 41 . Intercooler 51 is configured to cool intake air compressed by compressor 48 . A throttle valve (intake throttle valve) 49 is provided at a position downstream of the intercooler 51 in the intake passage 41 . The throttle valve 49 is configured to be able to adjust the flow rate of intake air flowing through the intake passage 41 . In this embodiment, the throttle valve 49 is a valve whose degree of opening can be changed continuously within a range from fully closed to fully open. The degree of opening of the throttle valve 49 is controlled by an HVECU 62 (see FIG. 3), which will be described later. Air flowing into the intake passage 41 passes through the airflow meter 50, the compressor 48, the intercooler 51, and the throttle valve 49 in this order, and is supplied to each cylinder 40 of the engine body 13a.

The turbine 53 is arranged in the exhaust passage 42 . A start catalytic converter 56 and an aftertreatment device 57 are provided downstream of the turbine 53 in the exhaust passage 42 . Further, the exhaust passage 42 is provided with a WGV device 500 described below.

The WGV device 500 is configured to allow the exhaust gas discharged from the engine body 13a to flow around the turbine 53 and adjust the amount of bypassed exhaust gas. The WGV device 500 includes a bypass passage 510 , a wastegate valve (WGV) 520 and a WGV actuator 530 .

A bypass passage 510 is connected to the exhaust passage 42 and configured to flow exhaust around the turbine 53 . The bypass passage 510 branches from a portion of the exhaust passage 42 upstream of the turbine 53 (for example, between the engine main body 13a and the turbine 53), and extends from a portion of the exhaust passage 42 downstream of the turbine 53 (for example, between the turbine 53 and the turbine 53). start catalytic converter 56).

The WGV 520 is arranged in the bypass passage 510 and configured to be able to adjust the flow rate of the exhaust gas guided from the engine body 13 a to the bypass passage 510 . As the flow rate of exhaust gas guided from the engine body 13a to the bypass passage 510 increases, the flow rate of exhaust gas guided from the engine body 13a to the turbine 53 decreases. The opening of WGV 520 changes the flow rate of exhaust gas flowing into turbine 53 (and thus the boost pressure). The closer the WGV 520 is closed (that is, the closer it is to the fully closed state), the more the flow rate of the exhaust gas flowing into the turbine 53 and the higher the pressure of the intake air (that is, the supercharging pressure).

WGV 520 is a negative pressure valve driven by WGV actuator 530 . The WGV actuator 530 includes a negative pressure driven diaphragm 531 and a negative pressure pump 533 . Diaphragm 531 is connected to WGV 520 , and WGV 520 is driven by negative pressure introduced to diaphragm 531 . In this embodiment, the WGV 520 is a normally closed valve, and the opening of the WGV 520 increases as the negative pressure acting on the diaphragm 531 increases.

The negative pressure pump 533 is connected to the diaphragm 531 via piping. In this embodiment, an electric pump that generates negative pressure is employed as the negative pressure pump 533 . When the negative pressure pump 533 operates, negative pressure acts on the diaphragm 531 and the WGV 520 opens. When the negative pressure pump 533 stops, the negative pressure no longer acts on the diaphragm 531 and the WGV 520 closes. The negative pressure pump 533 is configured to be able to adjust the magnitude of the negative pressure acting on the diaphragm 531 . The negative pressure pump 533 is controlled by an HVECU 62 (see FIG. 3) which will be described later. The HVECU 62 can adjust the magnitude of the negative pressure acting on the diaphragm 531 by controlling the drive amount of the negative pressure pump 533 .

Exhaust gas discharged from the engine main body 13a passes through either the turbine 53 or the WGV 520, and after harmful substances are removed by the start catalytic converter 56 and the aftertreatment device 57, it is released to the atmosphere. Aftertreatment device 57 includes, for example, a three-way catalyst.

The engine 13 is provided with an EGR (Exhaust Gas Recirculation) device 58 that causes exhaust gas to flow into the intake passage 41 . The EGR device 58 has an EGR passage 59 , an EGR valve 60 and an EGR cooler 61 . The EGR passage 59 connects a portion of the exhaust passage 42 between the starter catalytic converter 56 and the aftertreatment device 57 and a portion of the intake passage 41 between the compressor 48 and the air flow meter 50, thereby opening the exhaust passage 42. A part of the exhaust gas is taken out as EGR gas from the intake passage 41 and guided to the intake passage 41 . An EGR valve 60 and an EGR cooler 61 are provided in the EGR passage 59 . The EGR valve 60 is configured to be able to adjust the flow rate of EGR gas flowing through the EGR passage 59 . The EGR cooler 61 is configured to cool EGR gas flowing through the EGR passage 59 .

FIG. 3 is a diagram showing a vehicle control system according to this embodiment. 3 together with FIGS. 1 and 2, the vehicle control system includes an HVECU 62, an MGECU 63, and an engine ECU 64. As shown in FIG. In addition to the airflow meter 50 described above, the HVECU 62 includes an accelerator sensor 66, a vehicle speed sensor 67, an MG1 rotation speed sensor 68, an MG2 rotation speed sensor 69, an engine rotation speed sensor 70, a turbine rotation speed sensor 71, a boost pressure sensor 72, An SOC sensor 73, an MG1 temperature sensor 74, an MG2 temperature sensor 75, an INV1 temperature sensor 76, an INV2 temperature sensor 77, a catalyst temperature sensor 78, and a supercharger temperature sensor 79 are connected.

Accelerator sensor 66 outputs a signal to HVECU 62 according to the amount of accelerator operation (for example, the amount of depression of an accelerator pedal (not shown)). The accelerator operation amount is a parameter that indicates the amount of acceleration that the driver requests of the vehicle (hereinafter also referred to as "requested acceleration amount"). The greater the amount of accelerator operation, the greater the amount of acceleration requested by the driver. The vehicle speed sensor 67 outputs to the HVECU 62 a signal corresponding to the vehicle speed (that is, the running speed of the vehicle). The MG1 rotation speed sensor 68 outputs a signal corresponding to the rotation speed of the MG 14 to the HVECU 62 . The MG2 rotation speed sensor 69 outputs a signal corresponding to the rotation speed of the MG15 to the HVECU 62 . The engine rotation speed sensor 70 outputs a signal corresponding to the rotation speed of the output shaft 22 of the engine 13 to the HVECU 62 . The turbine rotation speed sensor 71 outputs a signal corresponding to the rotation speed of the turbine 53 of the supercharger 47 to the HVECU 62 . The boost pressure sensor 72 outputs a signal corresponding to the boost pressure of the engine 13 to the HVECU 62 . The supercharging pressure sensor 72 is provided in the intake manifold of the intake passage 41, for example, as shown in FIG. 2, and configured to detect the pressure in the intake manifold.

The SOC sensor 73 outputs to the HVECU 62 a signal corresponding to the SOC (State of Charge), which is the ratio of the remaining charge amount to the full charge amount (that is, storage capacity) of the battery 18 . The MG1 temperature sensor 74 outputs to the HVECU 62 a signal corresponding to the temperature of the MG14. The MG2 temperature sensor 75 outputs a signal corresponding to the temperature of the MG15 to the HVECU 62 . The INV1 temperature sensor 76 outputs a signal corresponding to the temperature of the first inverter 16 to the HVECU 62 . The INV2 temperature sensor 77 outputs a signal corresponding to the temperature of the second inverter 17 to the HVECU 62 . The catalyst temperature sensor 78 outputs a signal corresponding to the temperature of the aftertreatment device 57 to the HVECU 62 . The supercharger temperature sensor 79 outputs to the HVECU 62 a signal corresponding to the temperature of a predetermined portion of the supercharger 47 (for example, the temperature of the turbine 53).

The HVECU 62 includes a processor 62a, a RAM (Random Access Memory) 62b, a storage device 62c, an input/output port and a timer (not shown). A CPU (Central Processing Unit), for example, can be employed as the processor 62a. The RAM 62b functions as a working memory that temporarily stores data processed by the processor 62a. The storage device 62c is configured to be able to save the stored information. The storage device 62c includes, for example, ROM (Read Only Memory) and rewritable nonvolatile memory. The storage device 62c stores programs as well as information used in the programs (for example, maps, formulas, and various parameters). Various controls of the vehicle are executed by the processor 62a executing programs stored in the storage device 62c. Other ECUs (for example, the MGECU 63 and the engine ECU 64) also have the same hardware configuration as the HVECU 62. Although the HVECU 62, the MGECU 63, and the engine ECU 64 are separate in this embodiment, one ECU may have these functions.

HVECU 62 is configured to output a command for controlling engine 13 to engine ECU 64 . Engine ECU 64 is configured to control throttle valve 49 , spark plug 45 , injector 46 , WGV actuator 530 and EGR valve 60 according to instructions from HVECU 62 . The HVECU 62 can perform engine control through the engine ECU 64 .

HVECU 62 is configured to output commands for controlling each of MG 14 and MG 15 to MGECU 63 . The vehicle further includes a PCU (Power Control Unit) 19 . MGECU 63 is configured to control MG 14 and MG 15 through PCU 19 . The MGECU 63 generates a current signal (for example, a signal indicating the magnitude and frequency of the current) corresponding to the target torque of each of the MG 14 and the MG 15 according to a command from the HVECU 62 and outputs the generated current signal to the PCU 19. Configured. The HVECU 62 can perform motor control through the MGECU 63 .

The PCU 19 has a first inverter 16 , a second inverter 17 and a converter 65 . Each of MG14 and MG15 is electrically connected to PCU19. First inverter 16 and converter 65 are configured to perform power conversion between battery 18 and MG 14 . Second inverter 17 and converter 65 are configured to perform power conversion between battery 18 and MG 15 . PCU 19 is configured to supply power accumulated in battery 18 to each of MG 14 and MG 15 and to supply power generated by each of MG 14 and MG 15 to battery 18 . The PCU 19 is configured to be able to control the states of the MGs 14 and 15 separately. For example, the MG 15 can be brought into the power running state while the MG 14 is brought into the regenerative state (that is, the power generation state). PCU 19 is configured to be able to supply electric power generated by one of MG 14 and MG 15 to the other. MG14 and MG15 are configured to be able to exchange power with each other.

The vehicle is configured to perform HV running and EV running. HV travel is travel performed by the engine 13 and the MG 15 while the engine 13 is generating travel driving force. EV travel is travel performed by MG 15 with engine 13 stopped. When the engine 13 is stopped, combustion in the engine main body 13a is stopped. When the combustion in the engine main body 13a stops, the engine 13 no longer generates combustion energy (and thus driving force for driving the vehicle). The HVECU 62 is configured to switch between EV running and HV running depending on the situation. Also, the planetary gear mechanism 20 shown in FIG. 1 can function as a continuously variable transmission mechanism. The planetary gear mechanism 20 is configured to be able to continuously change the ratio of the rotation speed of the input element (carrier C) to the rotation speed of the output element (ring gear R). The rotation speed of the engine 13 can be adjusted by the HVECU 62 controlling the rotation speed of the MG 14 . The HVECU 62 can arbitrarily control the rotation speed of the MG 14 according to the magnitude and frequency of the current that flows through the MG 14 .

FIG. 4 is a collinear chart showing an example of the relationship between the rotational speeds of the sun gear S, the carrier C, and the ring gear R of the planetary gear mechanism 20 during HV running. Referring to FIG. 4, in an example of HV running, when torque output from engine 13 (that is, torque input to carrier C) is transmitted to drive wheels 24, reaction force is applied by MG 14 to planetary gear mechanism 20. of the sun gear S. Therefore, the sun gear S functions as a reaction force element. In HV running, the MG 14 is caused to output reaction torque with respect to the target engine torque in order to apply torque to the driving wheels 24 according to the target engine torque based on the acceleration request. This reaction torque can be used to cause the MG 14 to perform regenerative power generation.

FIG. 5 is a nomographic chart showing an example of the relationship between the rotational speeds of the sun gear S, the carrier C, and the ring gear R of the planetary gear mechanism 20 during EV running. Referring to FIG. 5, in EV traveling, engine 13 is stopped and MG 15 generates traveling driving force. During EV running, the HVECU 62 controls the spark plug 45 and the injector 46 so that the engine 13 does not perform combustion. Since the EV traveling is performed while the engine 13 is not rotating, the rotational speed of the carrier C becomes 0 as shown in FIG.

FIG. 6 is a collinear chart showing an example of the relationship between the rotational speeds of the sun gear S, the carrier C, and the ring gear R of the planetary gear mechanism 20 while the vehicle is stopped. Referring to FIG. 6, HVECU 62 controls engine 13 and MGs 14 and 15 to set the rotational speeds of sun gear S, carrier C, and ring gear R to 0, thereby stopping the vehicle from running. the car will come to a stop.

By the way, in known engine control, if an abnormality occurs in the supercharger during execution of supercharging and supercharging cannot be stopped, the continuation of supercharging deteriorates the controllability of the engine torque, resulting in excessive engine torque. becomes easier.

On the other hand, the vehicle according to this embodiment has the configuration described below, so that when the supercharger 47 becomes abnormal and supercharging cannot be stopped, the engine torque does not become excessively large. can be suppressed.

The HVECU 62 of the vehicle according to this embodiment operates when the WGV 520 is stuck at the opening degree during supercharging (that is, when the WGV is stuck closed), and when the WGV 520 is not stuck (that is, when the WGV is normal). The driving device 10 (for example, the engine 13, the MG 14, and the MG 15) is configured to be controlled such that fluctuations in engine power (that is, power output from the engine 13) are suppressed as compared to . The HVECU 62 according to this embodiment corresponds to an example of the "control device" according to the present disclosure.

FIG. 7 is a functional block diagram showing constituent elements of the HVECU 62 by function. With reference to FIG. 7 , HVECU 62 includes a normal running control unit 621 , a WGV diagnosis unit 622 and an evacuation running control unit 623 . Each of the units in the HVECU 62 is embodied by, for example, the processor 62a shown in FIG. 3 and a program executed by the processor 62a. However, the present invention is not limited to this, and each of these units may be embodied by dedicated hardware (electronic circuit).

The vehicle further includes an input device 101 that receives input from the user. The input device 101 is operated by a user and outputs a signal corresponding to the user's operation to the HVECU 62 . For example, the user can input a predetermined instruction or request to the HVECU 62 or set a parameter value to the HVECU 62 through the input device 101 . The communication method may be wired or wireless. As the input device 101, for example, various switches (push button switches, slide switches, etc.) provided around the driver's seat (eg, steering wheel or instrument panel) can be employed. However, the input device 101 is not limited to this, and various pointing devices (mouse, touch pad, etc.), keyboard, touch panel, etc. can be adopted as the input device 101 . The input device 101 may be an operation unit of a mobile device (for example, a smart phone) or an operation unit of a car navigation system.

The vehicle further includes a notification device 102 . Notification device 102 is configured to perform predetermined notification processing to a user (for example, a driver) when requested by HVECU 62 . Examples of notification device 102 include a display device (for example, a meter panel or head-up display), a speaker, and a lamp. The notification device 102 may be a display unit of a mobile device (for example, a smart phone) or a display unit of a car navigation system.

Normal running control unit 621 is configured to perform vehicle running control when WGV 520 is not stuck. The normal running control unit 621 is configured to switch between EV running and HV running depending on the situation. For example, normal running control unit 621 performs EV running under low-speed, low-load running conditions, and HV running under high-speed, high-load running conditions.

In HV running, the normal running control unit 621 determines the required engine power Pe (that is, the power required of the engine 13), and controls the engine 13 so that the power output from the engine 13 becomes the required engine power Pe. do.

The storage device 62c stores in advance a program (hereinafter, also referred to as "Pe calculation program") that defines the process for calculating the required engine power Pe. Although illustration is omitted, the storage device 62c also pre-stores a program that defines processing for controlling the drive device 10 according to the required engine power Pe calculated by the Pe calculation program. Furthermore, driving force acquisition information (that is, information indicating the required driving force corresponding to the amount of acceleration requested by the driver) and recommended operation line (that is, information indicating the target operating point for each required engine power Pe), which will be described later, It is stored in advance in the storage device 62c. The normal running control unit 621 determines the target operating point of the engine 13 based on the required engine power Pe, and controls the engine 13 so that the engine operating point becomes the target operating point. The target operating point is an engine operating point defined by the target engine torque and the target engine speed on the coordinate plane of the engine torque and the engine speed (hereinafter also referred to as "Te-Ne coordinate plane").

FIG. 8 is a flow chart showing the procedure for determining the control amount of the vehicle drive system 10 according to this embodiment. The processing shown in this flowchart is called from a main routine (not shown) at predetermined intervals and repeatedly executed.

Referring to FIG. 8 together with FIGS. 1 to 3, normal driving control unit 621, at step (hereinafter also simply referred to as “S”) 101, provides information indicating the state of the vehicle (for example, accelerator operation amount, selected and vehicle speed). Subsequently, the normal driving control unit 621 acquires the required driving force corresponding to the state of the vehicle in S102. When acquiring the required driving force, the normal traveling control unit 621 may refer to information indicating the relationship between the vehicle state and the required driving force (hereinafter also referred to as “driving force acquisition information”). The driving force acquisition information may be a map indicating the relationship between the accelerator operation amount and the vehicle speed, which is prepared in advance for each shift range.

In S103, the normal running control unit 621 multiplies the required driving force obtained in S102 by the vehicle speed, and adds a predetermined power loss to calculate the running power of the vehicle. In S104, the normal driving control unit 621 determines the amount of charging/discharging required of the battery 18 (hereinafter also referred to as the "requested amount of charging/discharging"), and adds the required amount of charging/discharging to the traveling power calculated in S103. positive value) is added to calculate the system power of the vehicle. The normal driving control unit 621 increases the required charge/discharge amount on the positive side as the SOC of the battery 18 is low, and can set the required charge/discharge amount to a negative value when the SOC of the battery 18 is high.

In S105, the normal travel control unit 621 determines whether the engine 13 is to be activated or stopped using the travel power and system power calculated as described above. For example, when the running power is greater than a predetermined value (hereinafter also referred to as “Th1”), normal running control unit 621 determines that engine 13 is to be operated. Also when the system power is greater than a predetermined value (hereinafter also referred to as “Th2”), the normal travel control unit 621 determines that the engine 13 should be operated. When the running power is equal to or less than Th1 and the system power is equal to or less than Th2, the normal running control unit 621 determines that the engine 13 should be stopped.

When the normal running control unit 621 determines that the engine 13 is to be operated, the running of the vehicle becomes HV running. In HV running, the processes after S106 are executed. By the processing after S106, the engine 13 is put into an operating state for vehicle running and/or power generation. On the other hand, when the normal running control unit 621 determines that the engine 13 should be stopped, the running of the vehicle changes to EV running. In EV running, a motor torque calculation process (not shown) is executed to calculate the torque of the MG 15 based on the required driving force.

At S106, the normal running control unit 621 calculates the required engine power Pe from the system power calculated at S104. Normal running control unit 621 can obtain required engine power Pe by performing predetermined arithmetic processing on the system power.

At S107, the normal running control unit 621 determines a target engine rotation speed (hereinafter also referred to as "target Ne") based on the required engine power Pe calculated at S106. In this embodiment, the normal running control unit 621 controls the intersection of the equal power line corresponding to the required engine power Pe and the recommended operation line (for example, line L3 in FIG. 9 to be described later) on the Te-Ne coordinate plane. (that is, the recommended operating point) is determined as the target operating point. Then, the normal travel control unit 621 determines the engine rotation speed at the target operating point as the target Ne. Further, the normal traveling control unit 621 determines the engine torque at the target operating point as the target engine torque (hereinafter also referred to as "target Te"). The requested engine power Pe and the target Ne correspond to an engine operating state command for the engine 13 and are transmitted from the normal running control section 621 to the engine ECU 64 .

In S108, the normal running control unit 621 calculates the torque of the MG 14 (hereinafter also referred to as "Tg") using the target Ne. The torque (that is, Tg) generated by the MG 14 is calculated so that the operating point of the engine 13 becomes the target operating point. The normal running control unit 621 can obtain Tg from the target Ne according to a formula including the planetary gear ratio of the planetary gear mechanism 20 (FIG. 1), for example. Tg corresponds to a torque command for the MG 14 and is transmitted from the HVECU 62 to the MGECU 63 .

In S109, the normal running control unit 621 calculates an engine direct torque (hereinafter also referred to as "Tep") using Tg. Tep corresponds to torque output from the planetary gear mechanism 20 (FIG. 1). When the engine torque is input to the carrier C of the planetary gear mechanism 20, the ring gear R of the planetary gear mechanism 20 outputs engine direct torque (Tep). The normal travel control unit 621 can obtain Tep from Tg according to a mathematical formula including the planetary gear ratio of the planetary gear mechanism 20, for example.

At S110, the normal driving control unit 621 calculates the torque of the MG 15 (hereinafter also referred to as "Tm") using the required driving force obtained at S102 and the Tep calculated at S109. The torque (that is, Tm) generated by the MG 15 is calculated so that the required driving force is output to the drive wheels 24 (FIG. 1). Normal running control unit 621 calculates Tm, for example, by subtracting Tep from the required driving force. Tm corresponds to a torque command for the MG 15 and is transmitted from the HVECU 62 to the MGECU 63 .

FIG. 9 is a diagram showing an example of a recommended operation line used in vehicle engine control according to this embodiment. Lines L1 to L3 and L41 and L42 are drawn on the Te--Ne coordinate plane shown in FIG. In FIG. 9, line L1 is a line indicating the maximum torque that the engine 13 can output. A line L2 is a line indicating the boundary (that is, the threshold value Th) between the supercharging state and the NA state (naturally aspirated state). Each of the lines L41 and L42 is an equal power line corresponding to the required engine power Pe. A line L41 indicates an equal power line corresponding to a small required engine power Pe, and a line L42 indicates an equal power line corresponding to a large required engine power Pe. Note that the engine power corresponds to the product of the engine rotation speed and the engine torque.

Referring to FIG. 9, line L3 is a recommended operating line (that is, a line indicating recommended operating points of engine 13). In this embodiment, the recommended operation line is the optimum fuel consumption line. When the operating point of the engine 13 is positioned on the optimum fuel efficiency line, the thermal efficiency of the engine 13 is optimized. In this embodiment, the target operating point is determined according to the recommended operating line (ie line L3) (see S107 in FIG. 8). For example, when the equal power line corresponding to the required engine power Pe is the line L41, the intersection E1 between the line L3 and the line L41 is the target operating point. When the equal power line corresponding to the required engine power Pe is the line L42, the intersection point E2 between the line L3 and the line L42 is the target operating point.

In this embodiment, the optimum fuel efficiency line is used as the recommended operating line, but the recommended operating line can be set arbitrarily. For example, the input device 101 (FIG. 7) may be configured to receive an input of the driving mode from the user. Then, the user may be allowed to select either the eco mode or the power mode through the input device 101 . The eco mode is a driving mode in which the engine 13 is operated with priority given to fuel efficiency over output power. The power mode is a driving mode in which the engine 13 is operated with priority given to output power over fuel efficiency. When the eco mode is selected by the user, the optimum fuel efficiency line is set as the recommended operation line. A power line that causes the engine 13 to output a large torque may be set.

Referring to FIG. 7 again, normal travel control unit 621 cooperatively controls engine 13, MG 14, and MG 15 so that the required driving force is output to drive wheels 24 shown in FIG. In EV running, the torque output by the MG 15 becomes the running driving force. In HV running, the torque obtained by adding the torque output by the engine 13 and the torque output by the MG 15 is the running driving force. In HV running, the normal running control unit 621 determines the required engine power Pe and the target operating point as described above, and controls the engine 13 so that the operating point of the engine 13 becomes the target operating point. Further, the normal travel control unit 621 executes supercharging control, which will be described below, while the engine 13 is operating.

FIG. 10 is a flow chart showing the procedure of supercharging control according to this embodiment. The processing shown in this flowchart is performed when the engine 13 is operating and the WGV 520 is not stuck (that is, the period during which the WGV diagnosis unit 622 shown in FIG. 7 determines that the WGV 520 is not stuck). is called from a main routine (not shown) and executed repeatedly.

Referring to FIG. 10 together with FIGS. 2 and 7, in S11, whether or not the target engine torque (target Te) is equal to or greater than a predetermined threshold value Th (eg, line L2 in FIG. 9) is determined by the normal running control unit. 621.

When the target engine torque is equal to or greater than the threshold Th (YES in S11), in S12, the normal driving control unit 621 requests the engine ECU 64 to perform supercharging (that is, to close the WGV 520 to the first opening). do. Engine ECU 64 issues a close command to WGV actuator 530 to close WGV 520 to the first degree of opening in accordance with a request from normal travel control unit 621 . The first degree of opening corresponds to the degree of opening during execution of supercharging. In this embodiment, the first degree of opening is the fully closed degree of opening. The engine ECU 64 issues a stop command (that is, a close command) to the negative pressure pump 533 of the WGV actuator 530 when the normal running control unit 621 requests execution of supercharging. When the negative pressure pump 533 stops, the negative pressure no longer acts on the diaphragm 531 . If the WGV 520 is in a state of normal operation, the negative pressure ceases to act on the diaphragm 531 so that the WGV 520 is closed and supercharging is performed. Note that when the WGV actuator 530 closes the WGV 520, the WGV 520 may be gradually closed from the fully opened opening to the fully closed opening.

On the other hand, if the target engine torque is less than the threshold Th (NO in S11), in S13 the normal driving control unit 621 instructs the engine ECU 64 to stop supercharging (that is, open the WGV 520 to the second opening). request. Engine ECU 64 issues an opening command to WGV actuator 530 to open WGV 520 to a second degree of opening, which is larger than the first degree of opening, in accordance with a request from normal running control unit 621 . The second degree of opening corresponds to the degree of opening when supercharging is stopped. In this embodiment, the second degree of opening is the full-open degree. When the engine ECU 64 receives a request to stop supercharging from the normal travel control unit 621 , the engine ECU 64 issues an operation command (that is, an open command) to the negative pressure pump 533 of the WGV actuator 530 . When the negative pressure pump 533 operates, the negative pressure generated by the negative pressure pump 533 acts on the diaphragm 531 . If the WGV 520 is in a normal operating state, negative pressure acts on the diaphragm 531 to open the WGV 520 and stop supercharging. In addition, when the WGV actuator 530 opens the WGV 520, the WGV 520 may be gradually opened from the fully closed opening to the fully open opening.

When either S12 or S13 is executed, the process is returned to the main routine. As described above, in the process of FIG. 10, when the target engine torque exceeds the threshold Th, the normal running control unit 621 requests the engine ECU 64 to perform supercharging, and when the target engine torque falls below the threshold Th, normal running is performed. The control unit 621 requests the engine ECU 64 to stop supercharging. Engine ECU 64 opens and closes WGV 520 by WGV actuator 530 in accordance with a request from normal travel control unit 621 .

Note that the processing in FIG. 10 can be changed as appropriate. For example, when the target engine torque matches the threshold value Th, the process may proceed to S13 instead of S12. The threshold Th may be a fixed value, or may be variable according to the state of the engine 13 (for example, engine speed). In order to suppress frequent opening and closing of the WGV 520 (and thus execution/stopping of supercharging), the threshold Th is provided with hysteresis (that is, the threshold Th when supercharging is executed and the threshold Th when supercharging is stopped). may be different).

Each of the first degree of opening and the second degree of opening can be arbitrarily set within a range in which the second degree of opening is greater than the first degree of opening. Each of the first degree of opening and the second degree of opening may be a fixed value, or may be variable depending on the situation. HVECU 62 may control WGV 520 such that the opening of WGV 520 gradually increases as the target engine torque decreases. HVECU 62 may control WGV 520 such that the opening of WGV 520 gradually decreases as the target engine torque increases.

Referring to FIG. 7 again, WGV diagnostic unit 622 instructs when normal running control unit 621 requests engine ECU 64 to stop supercharging (and when engine ECU 64 issues an open command to WGV actuator 530). It is configured to determine whether the WGV 520 is stuck at the first opening based on whether the WGV 520 has moved properly. When requesting the engine ECU 64 to stop supercharging, the normal running control unit 621 outputs a signal (hereinafter also referred to as “open command present signal”) indicating that an opening command is issued to the WGV actuator 530 . Send to The WGV diagnosis unit 622 diagnoses whether or not the WGV 520 is stuck at the first opening when the open command presence signal is received.

In this embodiment, WGV diagnosis section 622 determines whether or not WGV 520 has moved as instructed based on the behavior of boost pressure (for example, the value detected by boost pressure sensor 72). For example, if the supercharging pressure does not decrease despite the normal running control unit 621 requesting the engine ECU 64 to stop supercharging, the WGV diagnosis unit 622 determines that the WGV 520 is not operating as instructed (that is, the WGV 520 is is fixed at the first opening). Hereinafter, the state in which the WGV 520 is stuck at the first opening is also referred to as "closed stuck".

When the WGV diagnosis unit 622 determines that the WGV 520 is stuck closed, it notifies the driver of the vehicle of the occurrence of the abnormality through the notification device 102, and records the occurrence of the abnormality in the storage device 62c. configured to

In this embodiment, the WGV diagnosing section 622 diagnoses the WGV 520 to be stuck closed as described above, and determines that the WGV 520 is not stuck when no stuck closed. However, the present invention is not limited to this, and the WGV diagnostic unit 622 may be configured to diagnose whether or not the WGV 520 is stuck at the second opening in addition to being stuck closed. Hereinafter, the state in which the WGV 520 is stuck at the second opening is also referred to as "open stuck". WGV diagnosis unit 622 determines whether WGV 520 operates as instructed when normal running control unit 621 requests engine ECU 64 to perform supercharging (and when engine ECU 64 issues a close command to WGV actuator 530), for example. Based on whether or not, it may be determined whether WGV 520 is stuck open. Then, the WGV diagnostic unit 622 may be configured to determine that the WGV 520 is not stuck when neither the open sticking nor the closed sticking occurs.

WGV diagnostic unit 622 determines whether or not WGV 520 has moved as instructed, based on the behavior of the intake flow rate (for example, the detected value of airflow meter 50) instead of or in addition to the boost pressure. good too.

When the WGV 520 is stuck closed, the WGV diagnosis unit 622 changes the running control of the vehicle from running control by the normal running control unit 621 (hereinafter also referred to as “normal running control”) to running by the evacuation running control unit 623. control (hereinafter also referred to as “retreat control”). More specifically, WGV diagnosis unit 622 transmits a signal indicating that an abnormality has occurred (hereinafter, also referred to as a “control switching signal”) to normal running control unit 621 when a stuck closed door occurs. Upon receiving the control switching signal, the normal traveling control unit 621 instructs the evacuation traveling control unit 623 to execute the evacuation traveling control. As a result, the travel control of the vehicle is switched from the normal travel control to the evacuation travel control.

The evacuation driving control unit 623 executes evacuation driving control in accordance with the instruction from the normal driving control unit 621 . More specifically, the evacuation control unit 623 controls the driving device 10 (for example, the engine 13, the MG 14, and the MG 15) while suppressing fluctuations in engine power more than in normal traveling control, thereby causing the vehicle to evacuate. run.

FIG. 11 is a diagram for explaining evacuation control according to this embodiment. Referring to FIG. 11 together with FIG. 7, in normal running control, engine power transitions as indicated by line L51, for example. Normal travel control is executed by normal travel control unit 621 when WGV 520 is not stuck. In normal travel control, when the engine torque is less than the threshold Th, the engine torque is adjusted by the throttle valve 49 or the like with the WGV 520 open (that is, the supercharging is stopped), and the engine torque is less than the threshold Th. When it is large, the engine torque is adjusted by the throttle valve 49 or the like with the WGV 520 closed (that is, in a state in which supercharging is performed). In normal running control, the WGV 520 can be opened and closed according to the magnitude of the engine torque, so the controllability of the engine torque is good. Therefore, even if the required engine power Pe fluctuates greatly, the engine power can be controlled with high followability to the fluctuations in the required engine power Pe.

On the other hand, the emergency travel control is executed by the emergency travel control unit 623 when the WGV 520 is stuck closed. In the limp-away control, the engine torque is adjusted by the throttle valve 49 and the like in a state where the WGV 520 is closed (that is, a state in which supercharging is performed) regardless of the magnitude of the engine torque. Even when the engine torque is small, the controllability of the engine torque deteriorates because the engine torque is adjusted in a supercharged state. Therefore, when the required engine power Pe fluctuates greatly during acceleration of the vehicle, the engine power does not follow the required engine power Pe. With WGV 520 stuck closed, if demanded engine power Pe increases at a high rate of increase as shown by line L51, for example, it becomes difficult to control engine torque to an appropriate level. As a result, the engine torque becomes excessively large, and the engine power overshoots as indicated by line L52. As a result, the engine torque becomes excessively large and the MG 14 may over-rotate.

FIG. 12 is a diagram for explaining over-rotation of MG14 (MG1). In FIG. 12, Tg, Te, and Tep indicate the MG 14 torque, engine torque, and engine direct torque, respectively. Referring to FIG. 12, engine 13 and MG 14 are connected via planetary gear mechanism 20 as shown in FIG. increases, the rotation speed of the MG 14 tends to become excessively high.

Again referring to FIGS. 7 and 11, in order to prevent the engine torque from becoming excessively large, the limp-away control unit 623 suppresses fluctuations in engine power more than in normal travel control in limp-home control. configured as More specifically, the limp-away drive control unit 623 increases the required engine power Pe more moderately than during normal drive control when the vehicle is accelerating. For example, when the required engine power Pe calculated by normal running control unit 621 changes as indicated by line L51 in FIG. It changes as indicated by line L53.

Retreat running control unit 623 calculates required engine power Pe in a manner different from that of normal running control unit 621 . The procedure for calculating the required engine power Pe in the emergency travel control is basically the same as the procedure in normal travel control (that is, the procedure shown in FIG. 8). The increase in engine power Pe is restricted. As a result, an increase in engine power is suppressed compared to normal running control.

The limp-running control unit 623 stores the calculated required engine power Pe in the storage device 62c each time the required engine power Pe is calculated in S106 of FIG. The limp-running control unit 623 can acquire the magnitude of fluctuation in the required engine power Pe (for example, increase rate) from the history of the required engine power Pe stored in the storage device 62c. Note that the rate of increase is the amount of increase per unit time. Hereinafter, the increase rate of the required engine power Pe is also referred to as "Pe increase rate".

Retreat running control unit 623 limits the increase in required engine power Pe by, for example, correcting required engine power Pe. If the requested engine power Pe calculated in the same manner as in normal travel control is used as it is, the limp-away travel control unit 623 is controlled when the Pe increase rate exceeds a predetermined value (or when the Pe increase rate is predicted to exceed a predetermined value). , the required engine power Pe is corrected so that the rate of increase in Pe becomes equal to or less than a predetermined value. As a result, the increase in engine power is suppressed when the vehicle is accelerated, and the engine power increases more gently than in normal travel control.

By limiting the increase in the engine power as described above, the controllability of the engine torque is improved, and the engine power easily follows the required engine power Pe. In addition, by improving the followability of the engine power to the required engine power Pe, an excessive increase in the engine torque is suppressed. In addition, since the engine torque is less likely to become excessively large, the aforementioned excessive rotation of the MG 14 (see FIG. 12) is suppressed.

An upper limit for the Pe increase rate may be employed to limit the increase in engine power. The limp-running control unit 623 may be configured to control the driving device 10 so that the Pe increase rate is equal to or lower than a predetermined upper limit value (hereinafter also referred to as "first upper limit value"). For example, when it is determined in S106 in FIG. 8 that the Pe increase rate exceeds the first upper limit value, the limp-home run control unit 623 determines the required engine power Pe so that the Pe increase rate becomes the first upper limit value. may be configured to The upper limit value for the Pe increase rate may also be adopted in normal running control. That is, the normal travel control unit 621 may be configured to control the driving device 10 so that the Pe increase rate is equal to or lower than a predetermined upper limit (hereinafter also referred to as "second upper limit"). However, it is assumed that the first upper limit is smaller than the second upper limit. By setting the first upper limit value in the emergency travel control to be smaller than the second upper limit value in the normal travel control, an increase in engine power in the emergency travel control is suppressed more than in the normal travel control.

In this embodiment, the limp-run control unit 623 corrects the required engine power Pe when the WGV is stuck closed, thereby making the increase rate of the engine power when the WGV is stuck closed smaller than when the WGV is normal. In addition, each of the normal driving control unit 621 and the evacuation driving control unit 623 sets an upper limit value for the Pe increase rate, and makes the first upper limit value when the WGV is stuck closed smaller than the second upper limit value when the WGV is normal. . Information used in correcting the requested engine power Pe (hereinafter also referred to as "Pe correction information") and an upper limit value for the fluctuation rate of the requested engine power Pe (hereinafter also referred to as "Pe fluctuation upper limit value") are each: For example, it is stored in advance in the storage device 62c (see FIG. 7). Examples of Pe correction information include a correction map and a correction coefficient. Examples of the Pe fluctuation upper limit include the above-described first upper limit and second upper limit. Note that the increase in engine power may be limited only by correction, or may be limited only by the upper limit value of the Pe increase rate.

FIG. 13 is a flow chart showing the processing procedure of the WGV closed stuck diagnosis executed by the HVECU 62. As shown in FIG. The processing shown in this flowchart is executed while the vehicle is running in HV mode. The above-described processing of FIG. 8 is executed in parallel with the processing of FIG. When the WGV 520 is not stuck, the processing of FIG. 8 is executed in the above-described normal traveling control, and when the WGV 520 is stuck closed, in the above-described evacuation traveling control.

Referring to FIG. 13 together with FIG. 7, in S21, WGV diagnosis unit 622 determines whether or not the above-described open command signal has been received. The normal running control unit 621 transmits an open command presence signal to the WGV diagnosis unit 622 when requesting the engine ECU 64 to stop supercharging in S13 of FIG. That is, the fact that the WGV diagnostic unit 622 has received the open command signal means that the WGV actuator 530 has been issued an open command. If WGV diagnosis unit 622 does not receive the open command signal (NO in S21), the process does not proceed to S22 and thereafter, and S21 is repeatedly executed.

When WGV diagnosis unit 622 receives the open command signal (YES in S21), WGV diagnosis unit 622 diagnoses whether or not WGV 520 is stuck closed in S22. For example, the WGV diagnostic unit 622 monitors the detection value of the supercharging pressure sensor 72 to determine whether the supercharging pressure is rising normally. When the diagnosis is completed, the WGV diagnosis unit 622 determines in S23 whether or not the diagnosis result indicates the presence of closed fixation. If the diagnostic result is no closed fixation (NO in S23), the process returns to S21.

On the other hand, if the diagnosis result indicates that the vehicle is stuck closed (YES in S23), WGV diagnosis unit 622 transmits the aforementioned control switching signal to normal running control unit 621 . Furthermore, the WGV diagnosis unit 622 notifies the driver of the vehicle of the occurrence of the abnormality through the notification device 102, and records the occurrence of the abnormality in the storage device 62c. The WGV diagnosis unit 622 may notify the user that an abnormality has occurred in the WGV device 500 by, for example, turning on a WGV diagnosis MIL (Malfunction Indicator Light).

The above control switching signal switches the running control of the vehicle from the normal running control to the evacuation driving control, and the evacuation driving control unit 623 executes the evacuation driving control in S24. In the emergency travel control, the emergency travel control unit 623 performs the correction described above and sets the first upper limit value in S106 of FIG. 8 to limit the increase in engine power. As a result, fluctuations (more specifically, increase) in engine power are suppressed compared to normal running control. Evacuation driving control unit 623 evacuates the vehicle to a safe place (eg, roadside) by HV driving while limiting the increase in engine power.

The evacuation control unit 623 determines in S25 whether or not the vehicle has stopped, and continues the evacuation control (S24) until the vehicle stops (that is, while it is determined NO in S25). When the vehicle stops (YES at S25), the series of processes in FIG. 13 ends.

As described above, in the vehicle according to the present embodiment, the HVECU 62 controls the fluctuation of the engine power when the WGV is stuck closed (YES in S23) than when the WGV is normal (NO in S23). The driving device 10 is controlled (S24). By suppressing fluctuations in the engine power, it becomes easier for the HVECU 62 to control the engine torque, and the followability of the engine power to the required engine power Pe is improved. This suppresses an excessive increase in engine torque. Therefore, according to the vehicle described above, it is possible to prevent the engine torque from becoming excessively large when the supercharger 47 becomes abnormal and the supercharging cannot be stopped. In addition, since the engine torque is less likely to become excessively large, the aforementioned excessive rotation of the MG 14 (see FIG. 12) is suppressed.

In the above-described embodiment, when the WGV diagnosis finds the closed sticking, the HVECU 62 executes both notification of the occurrence of an abnormality and recording of the occurrence of the abnormality. Only one of recording may be performed, or neither notification nor recording may be performed.

Each of the air flow meter 50 and the supercharging pressure sensor 72 used in the WGV diagnosis according to the above embodiment is a sensor used in engine control of the vehicle. good too. A diagnostic sensor provided for acquiring data used for diagnosis (for example, at least one of boost pressure and intake flow rate) is used in WGV diagnosis instead of the air flow meter 50 and boost pressure sensor 72. good too.

The configuration of the engine 13 is not limited to the configuration shown in FIG. 2, and can be changed as appropriate. For example, the position of throttle valve 49 in intake passage 41 may be between air flow meter 50 and compressor 48 . Also, the cylinder layout is not limited to the straight type, and may be a V type or a horizontal type. The number of cylinders and the number of valves can also be changed arbitrarily.

In the above-described embodiment, binary control such as switching execution/stop of supercharging is performed with the threshold value Th as a boundary. may be configured to adjust the supercharging pressure to a desired magnitude by controlling .

Negative pressure pump 533 may be a mechanical pump driven by engine 13 . A pipe connecting the negative pressure pump 533 and the diaphragm 531 may be provided with a negative pressure regulating valve and an air release valve. WGV 520 may be a normally open valve. Furthermore, the driving method of the WGV 520 is not limited to the negative pressure type, and may be an electric type.

In the above embodiment, the degree of opening during execution of supercharging is the fully closed degree, and the degree of opening during stopping of supercharging is the degree of fully opening. can be set to For example, the opening during supercharging is set to be greater than the fully closed opening and less than 50%, and the opening during supercharging is set to be greater than 50% and fully open. The opening may be smaller than .

In the above embodiment, a gasoline engine is used as the engine 13 . However, the engine 13 is not limited to this, and any internal combustion engine can be adopted as the engine 13, and a diesel engine or the like can also be adopted. Further, in the above-described embodiment, an example in which the control device for controlling the drive device 10 in the above-described manner is applied to a hybrid vehicle has been described. may apply.

The embodiments disclosed this time should be considered as examples and not restrictive in all respects. The scope of the present invention is indicated by the scope of the claims rather than the description of the above-described embodiments, and is intended to include all modifications within the scope and meaning equivalent to the scope of the claims.

10 drive unit 13 engine 13a engine body 14, 15 MG 16 first inverter 17 second inverter 18 battery 19 PCU 20 planetary gear mechanism 21 output gear 22 output shaft 23, 30 rotor shaft , 24 drive wheel, 25 countershaft, 26 driven gear, 27, 31 drive gear, 28 differential gear, 29 ring gear, 32, 33 drive shaft, 36 oil pump, 38 electric oil pump, 40, 40a, 40b, 40c, 40d cylinder , 41 intake passage, 42 exhaust passage, 43 intake valve, 44 exhaust valve, 45 spark plug, 46 injector, 47 supercharger, 48 compressor, 49 throttle valve, 50 air flow meter, 51 intercooler, 53 turbine, 53a shaft, 56 start catalytic converter, 57 aftertreatment device, 58 EGR device, 59 EGR passage, 60 EGR valve, 61 EGR cooler, 62 HVECU, 62a processor, 62b RAM, 62c storage device, 63 MGECU, 64 engine ECU, 65 converter, 66 accelerator sensor, 67 vehicle speed sensor, 68 MG1 rotation speed sensor, 69 MG2 rotation speed sensor, 70 engine rotation speed sensor, 71 turbine rotation speed sensor, 72 boost pressure sensor, 73 SOC sensor, 74 MG1 temperature sensor, 75 MG2 temperature sensor , 76 INV1 temperature sensor, 77 INV2 temperature sensor, 78 catalyst temperature sensor, 79 supercharger temperature sensor, 101 input device, 102 notification device, 500 WGV device, 510 bypass passage, 520 waste gate valve, 530 WGV actuator, 531 diaphragm , 533 negative pressure pump, 621 normal running control unit, 622 WGV diagnosis unit, 623 evacuation running control unit, C carrier, P pinion gear, R ring gear, S sun gear.

Claims (9)

drive wheels;
a driving device that drives the driving wheels;
a control device configured to control the drive device,
The driving device includes a planetary gear having a first rotating element, a second rotating element, and a third rotating element, an engine that drives the first rotating element, and a first rotating element mechanically connected to the third rotating element. including a motor generator and a second motor generator that drives the drive wheels;
The planetary gear is configured to divide and transmit the torque output by the engine to the second rotating element and the third rotating element,
The planetary gear and the second motor generator are configured such that the power output from the second rotating element and the power output from the second motor generator are combined and transmitted to the drive wheels,
The engine includes an engine body that performs combustion, an intake passage and an exhaust passage connected to the engine body, a supercharger, a bypass passage connected to the exhaust passage, and a waste gate provided in the bypass passage. a valve;
The turbocharger includes a compressor provided in the intake passage and a turbine provided in the exhaust passage,
the bypass passage is configured to flow exhaust around the turbine;
The control device suppresses fluctuations in the power output from the engine when the wastegate valve is stuck at an opening degree during supercharging, compared to when the wastegate valve is not stuck. while the engine, the first motor-generator, and the second motor-generator are controlled to carry out limp-running of the vehicle ,
The drive device further includes a battery electrically connected to each of the first motor generator and the second motor generator,
In each of the normal travel control executed when the waste gate valve is not stuck and the evacuation travel control for the evacuation travel, the control device includes:
Acquiring the required driving force corresponding to the state of the vehicle;
calculating the running power of the vehicle by multiplying the required driving force by the vehicle speed and adding a predetermined power loss;
calculating a system power of the vehicle by adding a required charging/discharging amount required for the battery to the running power;
determining whether to operate the engine using the running power and the system power;
calculating a required engine power from the system power when it is determined to operate the engine;
Determining a target engine speed and a target engine torque based on the required engine power;
calculating a first torque command for the first motor generator using the target engine speed;
calculating an engine direct torque corresponding to the torque output from the second rotating element using the first torque command;
calculating a second torque command for the second motor generator using the required driving force and the engine direct torque;
A vehicle configured to perform The control device creates a recommended operation line indicating a target operating point defined by the target engine torque and the target engine speed of the engine on a Te-Ne coordinate plane, which is a coordinate plane of the engine torque and the engine speed. Equipped with a storage device that stores
The control device determines the target engine rotation speed and the target engine torque based on an intersection of an equal power line corresponding to the required engine power on the Te-Ne coordinate plane and the recommended operation line. 1. Vehicle according to 1 . further comprising a WGV actuator that drives the wastegate valve;
The control device instructs the WGV actuator to close the waste gate valve to the degree of opening during supercharging when the target engine torque of the engine exceeds a threshold value in the normal running control. and issuing an open command to the WGV actuator to open the wastegate valve when the target engine torque of the engine is below the threshold. further comprising at least one of a boost pressure sensor that detects the boost pressure of the engine and an air flow meter that detects the intake flow rate of the engine;
In the normal running control, the control device uses the behavior of at least one of the boost pressure and the intake flow rate when issuing the open command to the WGV actuator to control the waste gate valve to perform the supercharging. 4. The vehicle according to claim 3 , configured to determine whether or not it is stuck at the opening of the hour. The control device saves the calculated requested engine power in a storage device each time the requested engine power is calculated in the evacuation control, and stores the requested engine power based on the history of the requested engine power stored in the storage device. configured to obtain the magnitude of power fluctuations,
The control device adjusts the required engine power in a manner different from that in the normal driving control so that, in the limp driving control, an increase in the power output from the engine is restricted as compared with the normal driving control. Vehicle according to any one of claims 1 to 4 , wherein the vehicle is calculated. In the emergency travel control, the control device corrects the required engine power calculated in the same manner as in the normal travel control, so that the rate of increase in the power output from the engine is compared with that in the normal travel control. Vehicle according to any one of claims 1 to 5 , which is arranged to be smaller at The control device determines the required engine power so that a rate of increase of the required engine power is equal to or lower than a first upper limit value in the evacuation control,
The control device determines the required engine power so that the increase rate of the required engine power is equal to or lower than a second upper limit value in the normal running control,
The vehicle according to any one of claims 1 to 6 , wherein said first upper limit is smaller than said second upper limit. The control device is configured to control the drive device so that an amount of increase in power output from the engine per unit time is equal to or less than an upper limit value,
8. The upper limit value is smaller when the wastegate valve is stuck at the opening degree during execution of supercharging than when the wastegate valve is not stuck. Vehicles described in paragraph. The vehicle according to any one of claims 1 to 8 , wherein the degree of opening during execution of supercharging is a fully closed degree of opening.

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