JP2013193557A - Controller for hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a controller for a hybrid vehicle capable of quickly solving generation of motor lock.SOLUTION: A controller for a hybrid vehicle enlarges driving torque transmitted to a driving wheel by performing supercharging process (S21, S22) when motor locks are generated on a second motor generator during an operation of an engine (S14:YES, S16:YES, and S18:NO).

Description

  The present invention relates to a control device for a hybrid vehicle including an engine having a supercharger and a motor generator as power sources.

  Conventionally, for example, a vehicle described in Patent Document 1 has been proposed as a hybrid vehicle having an engine and a motor generator as a power source. Such a hybrid vehicle is provided with a travel mode in which the vehicle travels only by the output of the motor generator.

  By the way, in this travel mode, a so-called motor lock occurs in which the output shaft of the motor generator hardly rotates even when electric power corresponding to the amount of accelerator operation by the driver, that is, the required torque requested by the driver is supplied to the motor generator. There are things to do. When such motor lock occurs, the motor generator and the drive circuit for supplying power to the motor generator may generate excessive heat.

  Therefore, in the hybrid vehicle described in Patent Document 1, when it is determined that the motor lock has occurred while the engine is stopped, it is estimated whether or not the motor lock state has been released after a specified time from that point. It is estimated whether or not the motor generator is in an overheated state. The “specified time” is an estimated value of the time required to output torque from the engine when it is assumed that the engine has been started from the time when it is determined that the motor lock has occurred.

  Then, when it is estimated that the motor generator is overheated without being released from the locked state, torque limiting control for limiting the torque output from the motor generator is executed and the stopped engine is started. Then, since the value of the current flowing to the motor generator is reduced by executing the torque limit control, the heat generation in the motor generator and the drive circuit is suppressed, and the decrease in torque from the motor generator due to the execution of the torque limit control is suppressed. Will be supplemented with torque from the engine.

JP 2003-41966 A

  By the way, when the vehicle is started on an uphill road, the required torque requested by the driver may be balanced with the driving torque necessary for starting the vehicle. When the vehicle continues to stop on the spot and the motor lock occurs, the torque limit control and the engine start control as described above are executed, but the accelerator operation amount by the driver is not changed. Since the torque transmitted to the drive wheel and the required torque are still balanced, the motor lock is not released.

  These problems are not only caused when the vehicle starts on an uphill road, but when the vehicle is started with a large load, such as towing, when overcoming a step, braking by the parking brake is erroneously canceled. This may occur even when the vehicle is about to start in a state where it is not.

  The present invention has been made in view of such circumstances. An object of the present invention is to provide a control device for a hybrid vehicle that can quickly eliminate the generated motor lock.

In the following, means for achieving the above object and its effects are described.
The present invention is a control device for a hybrid vehicle that includes an engine having a supercharger and a motor generator as power sources, and the engine and the motor generator are drivingly connected to drive wheels. In this control device, when the motor lock is generated during the operation of the engine, the supercharging process for increasing the supercharging pressure by the supercharger is performed so that the torque transmitted to the drive wheels is increased. .

  Therefore, the torque of the engine increases due to the supercharging process, and the torque transmitted from the engine to the drive wheels increases, so that the drive wheels easily rotate. Therefore, the drive wheel in the stopped state can be quickly shifted to the rotating state, and the motor generator can be released by rotating the output shaft of the motor generator at an early stage.

  In addition, a hybrid vehicle including an engine and a motor generator as a power source is provided with a travel mode in which the engine is stopped and the vehicle travels only with torque from the motor generator. When a motor lock occurs during traveling in such a traveling mode, it is preferable to start the engine so that the torque transmitted to the drive wheels is increased. As a result, not only the torque from the motor generator but also the torque from the engine is transmitted to the drive wheels, and as a result, the drive wheels easily rotate. Therefore, the drive wheel in the stopped state can be promptly shifted to the rotating state, and the motor generator can be quickly released by rotating the output shaft of the motor generator.

  If the motor lock is not canceled even when the engine is started in response to the occurrence of the motor lock, the supercharging process is started. However, during the start of the engine or immediately after the start, there is a possibility that the supercharging pressure cannot be quickly increased even if the supercharger is driven. Therefore, when the motor lock is not resolved even when the engine is started, it is preferable to increase the opening of the throttle valve in conjunction with the execution of the supercharging process so that the torque transmitted to the drive wheels is further increased. As a result, the torque from the engine can be increased at an early stage, and the possibility of eliminating the motor lock is further increased.

  By the way, some hybrid vehicles include other motor generators that can generate electric power based on the operation of the engine, in addition to the motor generator that functions as a drive source. Such a hybrid vehicle is provided with a power split mechanism that connects an engine crankshaft, a motor generator, and another motor generator so as to be able to transmit power.

  In a hybrid vehicle having such a configuration, in order to transmit a large amount of torque increase from the engine due to the execution of the supercharging process to the drive wheel side, when executing the supercharging process, It is preferable to control the other motor generator so that the power generation amount is equal to or less than the power generation amount before the start of the supercharging process. By adopting such a control configuration, it is possible to increase the torque transmitted to the drive wheels by executing the supercharging process.

  Note that it is preferable to determine whether or not the motor generator is locked by whether or not the rotational speed of the output shaft of the motor generator or the rotational speed of the drive wheels is equal to or less than a determination value.

  Incidentally, when the motor lock is generated, a static frictional force is acting on the drive wheel, whereas when the motor lock is released, the drive wheel is rotating, so that the friction acting on the drive wheel is reduced. The force becomes a dynamic friction force smaller than the static friction force. Therefore, when the driving wheel starts to rotate, the driving wheel can be rotated with a smaller torque than when the driving wheel does not rotate. For this reason, it is preferable to terminate the supercharging process when the motor lock is eliminated by executing the supercharging process. Even in this case, it is unlikely that so-called hunting in which the supercharging process is executed intermittently will occur.

  In addition, by terminating the supercharging process after the motor lock is released, the fuel consumption of the vehicle can be reduced compared to the case where the supercharging process is continued even after the motor lock is released.

The schematic diagram which shows the hybrid vehicle carrying one Embodiment of the control apparatus of the hybrid vehicle concerning this invention. A map for determining the target engine speed from the total required power of the engine. The flowchart explaining the process routine for canceling | releasing the motor lock of a 2nd motor generator. (A)-(g) is a timing chart which shows an example at the time of canceling the motor lock which generate | occur | produced with the 2nd motor generator.

Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS.
As shown in FIG. 1, the hybrid vehicle is provided with a hybrid system 10 having an engine 100, a first motor generator 150 as another motor generator, and a second motor generator 160. The hybrid system 10 includes a power split mechanism 200 including a planetary gear mechanism, and the power split mechanism 200 is connected to the crankshaft 101 of the engine 100 and the first motor generator 150. That is, the power output from engine 100 is transmitted to first motor generator 150 via power split mechanism 200.

  The power split mechanism 200 is connected to the second motor generator 160 via a reduction gear 210 formed of a planetary gear mechanism, and to the drive wheels 20 via a speed reduction mechanism 220. At least one of the power from engine 100 and the power from second motor generator 160 is transmitted to reduction mechanism 220 via power split mechanism 200.

  The engine 100 of this embodiment includes a supercharger 120 that can adjust the supercharging pressure. An intake passage 102 and an exhaust passage 103 are connected to the combustion chamber 110 of each cylinder in the engine 100, and the intake amount that is the amount of intake air taken into the combustion chamber 110 is adjusted in the intake passage 102. A throttle valve 104 is provided. A compressor wheel 121 of the supercharger 120 is provided downstream of the throttle valve 104 in the intake passage 102, and a turbine wheel 122 of the supercharger 120 is provided in the exhaust passage 103. The compressor wheel 121 is connected to the turbine wheel 122 via the rotating shaft 123, and rotates integrally with the turbine wheel 122. Further, a bypass passage 130 is formed in the exhaust passage 103 so as to bypass the turbine wheel 122, and a waste gate valve 131 for adjusting the flow rate of the exhaust gas flowing toward the turbine wheel 122 is provided in the bypass passage 130. Yes.

  In the combustion chamber 110 of the cylinder, an air-fuel mixture consisting of fuel injected from the injector 105 and intake air is combusted, and power corresponding to this combustion is output to the crankshaft 101. Further, the burned gas is discharged into the exhaust passage 103 as exhaust. The turbine wheel 122 is rotated by the energy of the exhaust gas discharged into the exhaust passage 103 in this manner, whereby the compressor wheel 121 is rotationally driven, and the intake air compressed by the compressor wheel 121 is drawn into the combustion chambers 110 through the intake passage 102. The As the intake air amount increases due to the supercharging of the supercharger 120, the fuel injection amount from the injector 105 is also increased. As a result, the torque of engine 100 increases as compared to when turbocharger 120 is not driven.

  The rotational speed of the turbine wheel 122 is changed by controlling the opening degree of the waste gate valve 131 and adjusting the amount of exhaust gas passing through the bypass passage 130. That is, the supercharging pressure is a pressure corresponding to the opening degree of the waste gate valve 131.

  Each of the first and second motor generators 150 and 160 is a known synchronous generator motor including a rotor having a permanent magnet embedded therein and a stator wound with a three-phase coil. Each of the first and second motor generators 150 and 160 is connected to the battery 340 via the inverter 300 and the converter 320. Then, the alternating current generated by first motor generator 150 is converted into a direct current by inverter 300 and is stepped down through converter 320 and then charged to battery 340. When engine 100 is started, a direct current supplied from battery 340 is boosted through converter 320 and then converted into an alternating current by inverter 300, and this alternating current is supplied to first motor generator 150.

  The second motor generator 160 is connected to the battery 340 via the inverter 300 and the converter 320 in the same manner as the first motor generator 150. When starting, at low speed, and at acceleration, the DC current supplied from battery 340 is boosted by converter 320 and then exchanged with AC by inverter 300, and this AC current is supplied to second motor generator 160. .

  The first motor generator 150 functions as a starter motor that cranks the engine 100 when the engine 100 is started, and functions as a generator that generates power using the power of the engine 100 during operation of the engine 100. Further, during steady running and acceleration, the alternating current generated by the first motor generator 150 is supplied to the second motor generator 160 via the inverter 300. When the second motor generator 160 is driven by the alternating current supplied in this manner, the power is transmitted to the drive wheel 20 via the reduction gear 210, the power split mechanism 200, and the speed reduction mechanism 220.

  At the time of deceleration, the power from the drive wheels 20 is transmitted through the speed reduction mechanism 220, the power split mechanism 200, and the reduction gear 210, thereby driving the second motor generator 160. At this time, the second motor generator 160 functions as a generator to generate electric power, whereby the power transmitted from the drive wheels 20 to the second motor generator 160 is converted into electric power. The power thus converted is converted from an alternating current to a direct current by the inverter 300, and after being stepped down through the converter 320, the battery 340 is charged. That is, when decelerating, energy is recovered by converting kinetic energy into electrical energy and storing it in battery 340.

Next, the control device 400 that controls the hybrid system 10 will be described.
The control apparatus 400 of this embodiment has a power management control computer that controls the hybrid system 10 in an integrated manner, and a plurality of control units that can communicate with the power management control computer. That is, the control device 400 serves as a control unit such as a battery monitoring unit that monitors the amount of electricity stored in the battery 340, a motor control unit that controls the first and second motor generators 150 and 160, and an engine that controls the engine 100. It has a control unit.

  Such a control device 400 includes a first rotation sensor 501 for detecting the rotation speed of the first motor generator 150, a second rotation sensor 502 for detecting the rotation speed of the second motor generator 160, and the like. Are electrically connected. Then, control device 400 controls motor generators 150 and 160 according to the rotation speed detected based on the set output request to motor generators 150 and 160 and the detection signals from rotation sensors 501 and 502. Here, “control of motor generators 150 and 160” refers to control of inverter 300 and converter 320.

  The control device 400 is electrically connected with an air flow meter 511 for detecting the intake air amount and a crank position sensor 512 for detecting the engine speed, which is the speed of the crankshaft 101 of the engine 100. Yes. The control device 400 is electrically connected to a throttle position sensor 513 for detecting the opening of the throttle valve 104, a supercharging pressure sensor 514 for detecting a supercharging pressure by the supercharger 120, and the like. ing. Then, the control device 400 adjusts the intake request, the engine speed, the opening degree of the throttle valve 104, and the boost pressure detected based on the set output request to the engine 100 and the detection signals from the sensors 511, 512, 513, 514. Accordingly, fuel injection control, ignition timing control, intake air amount control, supercharging pressure control of the supercharger 120, and the like are performed in the engine 100.

  Further, the control device 400 includes an accelerator position sensor 521 for detecting an accelerator operation amount that is an operation amount of the accelerator pedal 21 by the driver, a shift position sensor 522 for detecting an operation position of the shift lever, and a vehicle speed. The vehicle speed sensor 523 and the like are electrically connected. Then, the control device 400 calculates a required torque to be output from the power split mechanism 200 to the speed reduction mechanism 220 based on the accelerator operation amount and the vehicle speed detected based on the detection signals from the sensors 521 and 523, and calculates the required torque. The engine 100 and the first and second motor generators 150 and 160 are controlled so that the corresponding required power is output to the speed reduction mechanism 220.

Here, the control of the engine 100 and the first and second motor generators 150 and 160 by the control device 400 will be described in detail.
The control device 400 sets the target rotational speed and the target engine torque, and controls the engine 100 so that the engine rotational speed and the engine torque become the target rotational speed and the target engine torque. The target rotational speed and the target engine torque are set as follows. That is, the required travel power of engine 100 and the required torque to be output to reduction mechanism 220 as the drive torque required for the vehicle are set based on the accelerator operation amount and the vehicle speed. Based on the state of charge of battery 340, the required charge / discharge power from battery 340 to engine 100 is calculated. Subsequently, the total required power of engine 100 is calculated as the sum of the required travel power based on the accelerator operation amount and the vehicle speed, and the required charge / discharge power of battery 340. Then, by applying to any one of the plurality of fuel consumption lines shown in FIG. 2, the target rotational speed Net and target engine torque of the engine 100 are determined to values according to the total required power Pet.

  FIG. 2 is a map for setting the target rotational speed Net according to the operating state of the engine 100. In this map, a plurality of fuel consumption lines corresponding to the driving state of the supercharger 120 are prepared in advance. FIG. 2 shows, as an example, a fuel efficiency optimal line L1 for optimizing the fuel efficiency of the vehicle when the supercharger 120 is not driven, and a fuel efficiency line L2 when the supercharging pressure is maximized. . Then, the control device 400 selects the fuel consumption line based on the operating state of the engine 100 at that time, specifically, the supercharging pressure by the supercharger 120, and responds to the total required power Pet based on the selected fuel consumption line. A target rotational speed Net of engine 100 is determined. Further, the control device 400 determines a target engine torque of the engine 100 according to the total required power Pet and the determined target rotational speed Net.

  Then, control device 400 performs feedback control of the power generation torque of first motor generator 150 so that the engine speed becomes the target speed. The control device 400 causes the second motor generator 160 to assist the shortage torque obtained by subtracting the power generation torque of the first motor generator 150 from the previously set required torque to be output to the speed reduction mechanism 220. The target motor torque and target rotation speed from the second motor generator 160 are determined. Then, control device 400 controls second motor generator 160 based on the determined target motor torque and target rotation speed.

  As described above, the first motor generator 150 is driven using a part of the power from the engine 100, and the second motor generator 160 is driven using the electric power generated there. Power from engine 100 and power from second motor generator 160 are transmitted to wheel 20. In this way, a part of the power from the engine 100 is distributed to the first motor generator 150, and the driving power of the driving wheel 20 is assisted by the power from the second motor generator 160, thereby adjusting the engine speed and the engine. The required power can be obtained while operating 100 in an efficient operating region.

  In addition, the control device 400 supplies electric power from the battery 340 to the second motor generator 160 during acceleration when the required power is large, etc., and increases the amount of assist by the second motor generator 160 to decelerate more power. Input to mechanism 220.

  Further, control device 400 supplies electric power to battery 340 by increasing the operation amount of engine 100 and increasing the amount of power generation in first motor generator 150 when the amount of electricity stored in battery 340 is small. At this time, the control device 400 may increase the supercharging pressure by the supercharger 120 in order to increase the operation amount of the engine 100. On the other hand, when the charged amount of battery 340 is sufficiently secured, control device 400 stops operation of engine 100 and outputs power corresponding to the required power from only second motor generator 160 to reduction mechanism 220. It is also possible to make it.

  In the present embodiment, the control device 400 uses the supercharger 120 when it is necessary to increase the target engine speed Net and the target engine torque of the engine 100 based on the operating state of the engine 100 set as described above. The supercharger 120 is controlled so that the target supercharging pressure is set to perform supercharging or the target supercharging pressure by the supercharger 120 is increased. Specifically, when the acceleration request of the vehicle is large and the amount of power stored in battery 340 is not so large, total required power Pet of engine 100 is calculated to be large. In such a case, the control device 400 sets the target supercharging pressure by the supercharger 120 to a large value. On the other hand, when the total required power Pet of the engine 100 is not so large, the control device 400 sets the target supercharging pressure by the supercharger 120 to a small value or makes supercharging by the supercharger 120 unnecessary. To do.

  The control device 400 basically controls the supercharger 120 so that the supercharging pressure detected based on the detection signal from the supercharging pressure sensor 531 becomes the target supercharging pressure. 120 is controlled. Specifically, the control device 400 adjusts the opening degree of the waste gate valve 131 so as to adjust the amount of exhaust gas flowing to the turbine wheel 122 side.

  By the way, when the hybrid vehicle starts, the driving torque necessary for rotating the driving wheels 20 and the driving torque transmitted to the driving wheels 20 by driving at least one of the engine 100 and the second motor generator 160 are obtained. If they are balanced, a so-called motor lock is generated in which the drive wheels 20 and the output shaft of the second motor generator 160 connected to the drive wheels 20 do not rotate. When the motor lock occurs, the current concentrates and flows only in one of the three-phase coils constituting the second motor generator 160 to cause heat generation. In order to eliminate such motor lock, it is preferable to increase the driving torque transmitted to the driving wheel 20 and rotate the driving wheel 20.

  Motor lock is likely to occur when a large force acting on the vehicle prevents the vehicle from moving forward. In such a case, when starting a vehicle on an uphill road, if the vehicle gets over a step on the road surface, or if the vehicle is started in a heavy load state such as towing, the parking brake will not be released accidentally. The case where it is going to start a vehicle in a state is mentioned.

  Therefore, next, a processing routine for increasing the driving torque transmitted to the driving wheel 20 when the motor lock is generated in the second motor generator 160 and quickly releasing the motor lock is shown in the flowchart shown in FIG. The description will be given with reference.

  The processing routine shown in FIG. 3 is a processing routine that is executed at predetermined intervals set in advance. In this processing routine, the control device 400 acquires the accelerator operation amount detected based on the detection signal from the accelerator position sensor 521, and determines whether or not the accelerator pedal 21 is operated based on the accelerator operation amount. (Step S11). When the accelerator pedal is not operated (step S11: NO), the control device 400 once ends this processing routine.

  On the other hand, when accelerator pedal 21 is operated (step S11: YES), control device 400 has the number of rotations of the output shaft of second motor generator 160 detected based on the detection signal from second rotation sensor 502. NMG2 is acquired (step S12). Subsequently, control device 400 increments elapsed time Tr by “1” (step S13), and rotation speed NMG2 of second motor generator 160 acquired in step S12 is less than preset lock determination value NMG2th. It is determined whether or not (step S14). This lock determination value NMG2th is a value set as a reference for determining whether or not motor lock has occurred in second motor generator 160, and is set to a value close to “0” (≠ 0).

  When the rotational speed NMG2 is equal to or greater than the lock determination value NMG2th (step S14: NO), it can be determined that the motor lock has not occurred, so the control device 400 resets the elapsed time Tr to “0” (step S15). Then, the process proceeds to step S17 which will be described later. On the other hand, when the rotational speed NMG2 is less than the lock determination value NMG2th (step S14: YES), there is a possibility that a motor lock has occurred, so the controller 400 sets the elapsed time Tr updated in step S13 in advance. It is determined whether or not the timer determination value Trth is exceeded (step S16). When the elapsed time Tr is less than the timer determination value Trth (step S16: NO), the control device 400 proceeds to the next step S17.

  In step S17, control device 400 selects a fuel consumption line according to the operating state of engine 100 at that time, and sets target engine speed Net and target engine torque Tet of engine 100 according to the total required power Pet. . At this time, when the supercharger 120 is not driven, the optimum fuel consumption line L1 is selected from the respective fuel consumption lines, and when the supercharger 120 is being driven, the excess fuel consumption line at this point of the fuel consumption line is selected. A fuel consumption line corresponding to the supply pressure is selected (see FIG. 2). Then, based on the selected fuel consumption line, a target rotational speed Net corresponding to the total required power Pet is set, and a target engine torque Tet corresponding to the target rotational speed Net and the total required power Pet is set. When the operation of the engine 100 is stopped, both the target rotational speed Net and the target engine torque Tet are set to “0”. Thereafter, the control device 400 once ends this processing routine.

  On the other hand, if the elapsed time Tr exceeds the timer determination value Trth (step S16: YES), it can be determined that the motor lock has occurred, so the control device 400 determines whether the operation of the engine 100 is stopped. It is determined whether or not (step S18).

  When operation of engine 100 is stopped (step S18: YES), control device 400 performs a start process for starting operation of engine 100 (step S19). That is, the control device 400 controls the drive of the first motor generator 150 to perform the cranking operation of the engine 100 and starts the fuel injection control. Note that the supercharger 120 is not driven when the engine 100 is started.

Then, the control device 400 resets the elapsed time Tr to “0” (step S20), and the process proceeds to step S17 described above.
On the other hand, when the engine 100 is in operation (step S18: NO), the control device 400 performs a supercharging process for controlling the supercharger 120 to increase the supercharging pressure (step S21). In the present embodiment, the supercharging pressure is set to the maximum by the supercharging process. Subsequently, the control device 400 sets the target rotational speed Net and the target engine torque Tet of the engine 100 so that the engine torque becomes large (step S22).

  That is, in step S22, the total required power Pet of the engine 100 is made larger than before the supercharging process is executed. Specifically, the fuel efficiency line L2 for the maximum boost pressure is selected from the fuel efficiency lines shown in FIG. 2, and the target rotational speed set before the supercharging process is executed based on the fuel efficiency line L2. The total required power Pet according to Net is determined. As a result, as shown in FIG. 2, the total required power Pet is changed from the first total required power Pet1 determined before the supercharging process without changing the target rotational speed Net before and after the start of the supercharging process. Is also changed to a large second total required power Pet2. Further, the target engine torque Tet set to a value corresponding to the total required power Pet and the target rotational speed Net is also changed to a larger value than before the supercharging process is executed. In the present embodiment, even when the supercharging process is started, feedback control of the first motor generator 150 is performed so that the power generation torque of the first motor generator 150 is equal to that before the supercharging process is started. Is called.

Thereafter, the control device 400 once ends this processing routine.
Next, the operation when the hybrid vehicle of the present embodiment starts will be described with reference to the map shown in FIG. 2 and the timing charts shown in FIGS. In FIG. 4, the “motor lock flag” is a flag that is set to “ON” from the time when it is determined that the motor lock is generated to the time when it is determined that the motor lock is released. The “supercharging flag” is a flag that is set to “on” while the above supercharging process is being executed to cancel the motor lock.

  As a premise, it is assumed that the vehicle is stopped on the uphill road and the engine 100 is operating while the vehicle is stopped. However, even when engine 100 is in operation, supercharger 120 is not driven.

  When the driver operates the accelerator pedal 21 to start the vehicle at the first timing t1, the travel request power to the engine 100 based on the accelerator operation amount AC and the vehicle speed VS at this time and the output to the speed reduction mechanism 220 should be output. The required torque is set.

  Then, when the total required power Pet, which is the sum of the required travel power and the required charge / discharge power of the battery 340, is calculated, the supercharger 120 is not driven at this time, so the supercharger 120 is not driven. The target engine speed Net and the target engine torque Tet of the engine 100 corresponding to the total required power Pet are determined using the hourly fuel efficiency optimum line L1. As a result, as shown in FIGS. 4B and 4E, the engine torque Te output from the engine 100 increases as the accelerator operation amount AC increases.

  When the accelerator operation is performed, the target motor torque required for second motor generator 160 is determined based on the required torque and the power generation torque of first motor generator 150. Then, as shown in FIGS. 4B and 4F, the motor torque Tmg2 output from the second motor generator 160 increases as the accelerator operation amount AC increases. When the torque from at least one of the engine 100 and the second motor generator 160 is transmitted to the speed reduction mechanism 220 as described above, it is transmitted to the drive wheels 20 as shown in FIGS. The drive torque Tw gradually increases as the accelerator operation amount AC increases. When the second timing t2 elapses, the accelerator operation amount AC becomes constant, so that the engine torque Te and the motor torque Tmg2 become constant, and the drive torque Tw also becomes constant.

  After the first timing t1, as shown in FIGS. 4 (a) and 4 (g), the drive wheels 20 are output even though the drive torque Tw is output to the drive wheels 20 by the accelerator operation by the driver. Since the vehicle cannot rotate, the vehicle speed VS remains “0”. In this case, the output shaft of the second motor generator 160 that is drivingly connected to the drive wheels 20 cannot rotate.

  Such a state continues even at the third timing t3 when the predetermined time KT has elapsed from the first timing t1. The predetermined time KT is a value obtained by multiplying the interval at which the processing routine shown in FIG. 3 is executed by the timer determination value Trth. Therefore, as shown in FIGS. 4C and 4D, it is determined that the motor lock has occurred in the second motor generator 160 at the third timing t3. Then, as shown in FIG. 4 (e), the supercharging process is started at the third timing t3, and the engine torque Te output from the engine 100 is quickly increased by driving the supercharger 120.

  Here, as a method of increasing the engine torque Te, there is a method of increasing the opening degree of the throttle valve 104 in addition to boosting the supercharging pressure by driving the supercharger 120. In this case, the intake amount sucked into the combustion chamber 110 and the fuel injection amount from the injector 105 are increased by increasing the opening of the throttle valve 104, and the engine speed is increased. Then, the intake amount and the fuel injection amount further increase due to the increase in the engine speed. By repeating the increase in the engine speed and the increase in the intake air amount and the fuel injection amount, the engine torque Te gradually increases over a period of time. On the other hand, in the present embodiment in which the supercharging pressure is increased, the intake air amount into the combustion chamber 110 and the fuel injection amount from the injector 105 increase at a stretch by the start of supercharging, so that the engine torque Te becomes early. growing. That is, as shown in FIG. 4 (e), the increasing speed of the engine torque Te in the present embodiment becomes faster than when the opening degree of the throttle valve 104 is increased without changing the supercharging pressure.

  In the present embodiment, as described above, even when the supercharging process is started, the power generation torque of the first motor generator 150 is not changed from that before the supercharging process is started. Therefore, increasing the engine torque Te increases the torque transmitted from the engine 100 to the drive wheels 20 via the power split mechanism 200 or the like.

  Further, as shown in FIG. 4F, before and after the start of the supercharging process, the motor torque Tmg2 from the second motor generator 160 has not been changed from before the supercharging process was started. Therefore, as shown in FIG. 4G, when the engine torque Te increases due to the execution of the supercharging process, the drive torque Tw increases. Then, the driving wheel 20 starts rotating, and the vehicle speed VS of the vehicle gradually increases as shown in FIG.

  Then, at the fourth timing t4 when the vehicle speed VS exceeds the specified speed VSth, the rotation speed NMG2 of the second motor generator 160 exceeds the lock determination value NMG2th, so that the motor lock of the second motor generator 160 is It is determined that it has been eliminated, and the supercharging process is terminated. At this time, the supercharger 120 is controlled so that the supercharging pressure gradually decreases from the maximum toward “0”. That is, the opening degree of the waste gate valve 131 is gradually reduced from the fully opened state.

  At this time, the fuel consumption line for setting the target engine torque Tet is set to a line corresponding to the boost pressure to be reduced. At the fifth timing t5 when the supercharging pressure becomes “0”, the set fuel efficiency line is set to the fuel efficiency optimal line L1 for when the supercharger 120 is not driven. That is, in the present embodiment, when the motor lock is released, the supercharging process is promptly terminated.

As described above, in the present embodiment, the following effects can be obtained.
(1) When the motor lock occurs in the second motor generator 160 during the operation of the engine 100, the engine torque Te is increased by the supercharging process, and the drive torque Tw transmitted to the drive wheels 20 is increased. Therefore, the drive wheel 20 is easy to rotate. Therefore, the driving wheel 20 in the stopped state can be quickly shifted to the rotating state, and the output shaft of the second motor generator 160 can be rotated at an early stage so that the motor lock can be eliminated.

  (2) Since the magnitude of the power generation torque of the first motor generator 150 is not changed when the supercharging process is executed, the increase in the engine torque Te due to the supercharging process is transmitted to the drive wheels 20 as it is. . Thus, by increasing the drive torque Tw, the motor lock of the second motor generator 160 can be quickly eliminated.

  (3) Since the supercharging pressure is set to the maximum in the supercharging process of the present embodiment, the engine torque Te can be increased at a stretch by executing the supercharging process. As a result, the motor lock of the second motor generator 160 can be quickly eliminated. Further, when the motor lock is detected, even if the supercharger 120 has already been driven, the supercharging pressure can be increased by the supercharging process, and the possibility that the driving torque Tw will increase is increased. can do.

  (4) As a method of increasing the engine torque Te, a method of increasing the opening degree of the throttle valve 104 of the engine 100 can be considered. However, in this method, the responsiveness is lower than in the case of the present embodiment in which the boost pressure is increased, and a slight delay may occur before the engine torque Te actually increases. Therefore, in a hybrid vehicle equipped with the engine 100 having the supercharger 120, when the motor lock occurs in the second motor generator 160, the motor lock can be quickly eliminated by increasing the supercharging pressure. Will be able to.

  (5) When the motor lock is generated in the second motor generator 160 while the engine 100 is stopped, the engine 100 is started to output the engine torque Te. Then, not only the motor torque Tmg2 from the second motor generator 160 but also the engine torque Te is transmitted to the drive wheels 20, and as a result, the drive wheels 20 are easily rotated. Therefore, the driving wheel 20 in the stopped state can be quickly shifted to the rotating state, and the output shaft of the second motor generator 160 can be rotated at an early stage so that the motor lock can be eliminated.

  Further, even when the motor lock can be eliminated without driving the supercharger 120, the increase in fuel consumption of the vehicle is suppressed as compared with the case where the supercharger 120 is driven. Will be able to.

  (6) On the other hand, when the motor lock is not resolved even when the engine 100 is started, the engine torque Te from the engine 100 can be increased by executing the supercharging process. As a result, the motor lock of the second motor generator 160 can be canceled.

  (7) By the way, when the motor lock is generated in the second motor generator 160, the static frictional force acts on the drive wheel 20, whereas when the motor lock is released, the drive is performed. Since the wheel 20 is rotating, the frictional force acting on the drive wheel 20 becomes a dynamic frictional force smaller than the static frictional force. Therefore, even if the driving torque Tw transmitted to the driving wheel 20 is reduced by terminating the supercharging process when the motor lock is released, the driving wheel 20 can continue to rotate. Therefore, it is possible to reduce the possibility of so-called hunting in which the supercharging process is executed intermittently.

  Further, after the motor lock is released, the supercharging process is terminated, so that the supercharging pressure becomes lower than that during execution of the supercharging process. Therefore, the fuel consumption of the vehicle can be reduced compared to the case where the supercharging process is continued even after the motor lock is released.

The embodiment may be changed to another embodiment as described below.
When the motor lock of the second motor generator 160 is canceled by executing the supercharging process, the supercharging process is performed until at least one of the following conditions (A), (B), and (C) is satisfied. You may make it continue.
(A) The accelerator pedal 21 is not operated.
(B) The operation of the engine 100 is stopped by the control device 400.
(C) A predetermined time elapses from the time when the motor lock is released (fourth timing t4).

  Whether the motor lock is generated in the second motor generator 160 may be determined based on the rotation speed of the drive wheel 20 instead of the rotation speed NMG2 of the second motor generator 160.

  When the operation of the engine 100 is started when the motor lock is generated in the second motor generator 160 while the operation of the engine 100 is stopped, and the motor lock is not released even if the engine 100 is started In addition to executing the supercharging process, the opening degree of the throttle valve 104 may be increased.

  During the start of the engine 100 or immediately after the start, there is a possibility that the supercharging pressure cannot be quickly increased even if the supercharger 120 is driven. Therefore, when the motor lock cannot be released only by starting the stopped engine 100, the engine torque Te is increased early by increasing the supercharging pressure while increasing the opening of the throttle valve 104. It becomes possible to increase the size, and the possibility of eliminating the motor lock is further increased.

When the motor lock is released, it is preferable to terminate the supercharging process and return the opening degree of the throttle valve 104 to the opening degree corresponding to the accelerator operation amount AC.
When the motor lock is generated in the second motor generator 160 while the operation of the engine 100 is stopped, the supercharging process may be started together with the start of fuel injection from the injector 105 by starting the engine 100.

  In addition, when the supercharging process is started because the motor lock is generated in the second motor generator 160, the motor torque Tmg2 is decreased if the driving torque Tw is larger than that before the supercharging process is started. You may make it do. As a result, heat generation in the second motor generator 160 and the inverter 300 during the motor lock can be suppressed.

  When the supercharging process is started because the motor lock has occurred in the second motor generator 160, if the driving torque Tw is larger than before the supercharging process is started, the first motor generator 150 The first motor generator 150 may be controlled so that the power generation torque is increased.

  If the supercharging process is started because the motor lock has occurred in the second motor generator 160, the first motor generator 150 may be controlled so that the power generation torque of the first motor generator 150 is reduced. Good. In this case, the drive torque Tw transmitted to the drive wheels 20 can be further increased by the amount that the power generation torque of the first motor generator 150 is reduced. As a result, the possibility of releasing the motor lock of the second motor generator 160 can be further increased.

  In the supercharging process executed to cancel the motor lock in the second motor generator 160, if the supercharging pressure is higher than before the supercharging process starts, the supercharging pressure must not be maximized. Also good.

  When starting the supercharging process, if the target engine torque Tet can be determined to be a larger value than before the supercharging process is started, the total required power Pet is set to a value that makes the target engine speed Net of the engine 100 smaller. You may decide to.

  When the motor lock in the second motor generator 160 is detected, the supercharging pressure may already be maximum. In this case, it is preferable to increase the opening of the throttle valve 104 so that the engine torque Te increases.

  The supercharger may be an engine-driven supercharger that uses the rotation of the crankshaft 101 instead of a supercharger that drives using the exhaust of the engine 100, or from an electric motor such as a motor. It may be an electric supercharger that uses driving force.

  DESCRIPTION OF SYMBOLS 20 ... Drive wheel, 100 ... Engine, 101 ... Crankshaft, 104 ... Throttle valve, 120 ... Supercharger, 150 ... 1st motor generator as another motor generator, 160 ... 2nd motor generator, 200 ... Power Dividing mechanism, 400... Control device, NMG2... Rotation speed, NMG2th.

Claims (6)

An engine having a supercharger and a motor generator are provided as power sources, and the engine and the motor generator are applied to a hybrid vehicle that is drivingly connected to drive wheels.
A control apparatus for a hybrid vehicle that performs a supercharging process for increasing a supercharging pressure by the supercharger so that a torque transmitted to the driving wheel is increased when a motor lock is generated during operation of the engine.   2. The hybrid vehicle control device according to claim 1, wherein when the motor is locked while the operation of the engine is stopped, the engine is started so that a torque transmitted to the drive wheel is increased.   3. When the engine lock is not released even when the engine is started, the opening of the throttle valve is increased together with the execution of the supercharging process so that the torque transmitted to the drive wheels is further increased. The hybrid vehicle control apparatus described. Hybrid vehicles
Another motor generator capable of generating electricity based on the operation of the engine;
A power split mechanism that connects the crankshaft of the engine, the motor generator, and the other motor generator so that power can be transmitted;
2. When the supercharging process is executed, the other motor generator is controlled such that the power generation amount of the other motor generator is equal to or less than the power generation amount before the start of the supercharging process. The control apparatus of the hybrid vehicle as described in any one of-Claim 3.   5. The motor lock according to claim 1, wherein the motor lock is determined to be generated when the rotation speed of the output shaft of the motor generator or the rotation speed of the drive wheel is equal to or less than a determination value. Hybrid vehicle control device.   The control apparatus for a hybrid vehicle according to any one of claims 1 to 5, wherein when the motor lock is eliminated by executing the supercharging process, the supercharging process is terminated.