JP2010116032A - Hybrid vehicle and method of controlling the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To control an internal combustion engine more appropriately in a hybrid vehicle having the internal combustion engine and two electric motors, thereby avoiding excessive rotation of one of the electric motors due to the sudden deceleration of a driving wheel, without worsening emissions. <P>SOLUTION: In the hybrid vehicle having an engine and motors MG1 and MG2, if fuel is injected to at least one of a plurality of combustion chambers when fuel injection to each of the combustion chambers should be stopped as it is determined that excessive rotation of the motor MG1 might happen, the fuel injection to at least one of the plurality of combustion chambers is stopped (steps S330-S390) on condition that the amount of fuel necessary to ignite an air-fuel mixture is supplied. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a hybrid vehicle and a control method thereof.

Conventionally, an internal combustion engine, a planetary gear mechanism including a planetary carrier connected to a crankshaft of the internal combustion engine, a first electric motor capable of generating electricity connected to a sun gear of the planetary gear mechanism, and a ring gear of the planetary gear mechanism And a hybrid vehicle including a second electric motor capable of outputting power to a ring gear shaft as a driving shaft coupled to the driving wheel and a battery capable of exchanging electric power with the first and second electric motors. It is known (see, for example, Patent Document 1). In this type of hybrid vehicle, when the gripping force of the driving wheel recovers after slipping due to idling of the driving wheel, the rotational speed of the driving wheel rapidly decreases. Is very large compared to the moment of inertia of the first electric motor, the rotational speed of the internal combustion engine does not decrease so much while the rotational speed of the first electric motor increases rapidly, and the rotational speed of the internal combustion engine is relatively low. If it is high, the rotation speed of the first electric motor may exceed the allowable maximum rotation speed. For this reason, in the hybrid vehicle described in Patent Document 1, when the drive wheel slips, the allowable maximum rotational speed in the control of the first electric motor is set to a smaller value than usual, and the first electric motor A regenerative torque is output from the first electric motor so that the rotational speed does not exceed the allowable maximum rotational speed, and the first electric motor is prevented from over-rotating when the gripping force of the drive wheels is restored. Conventionally, an internal combustion engine, power transmission means including first and second rotating electrical machines, an inverter device that drives the first and second rotating electrical machines, a power storage device, and fuel injection control of the internal combustion engine are performed. 2. Description of the Related Art A hybrid vehicle is known that includes an internal combustion engine control device to be implemented and a hybrid control device that commands a torque control amount to the internal combustion engine control device and controls driving of an inverter device (see, for example, Patent Document 2). . In this hybrid vehicle, the fuel cut of the internal combustion engine is performed assuming that the vehicle is in a braking state when the torque control amount of the internal combustion engine is a negative value.
JP 2007-20993 A JP-A-10-238381

  Here, the fuel supply to the combustion chamber of the internal combustion engine should be stopped when the drive wheel suddenly decelerates or locks due to the recovery of the grip force after the drive wheel slips or the sudden braking of the vehicle. For example, even if the rotational speed of the internal combustion engine is relatively high, the rotational speed of the internal combustion engine can be reduced and the output torque from the internal combustion engine can be reduced to suppress over-rotation of the first electric motor. Conceivable. However, if the fuel supply is interrupted before the amount of fuel to be supplied is supplied to the combustion chamber while the fuel is being supplied to any of the combustion chambers, the mixture cannot be ignited. There is a risk that not a little fuel will be introduced into the catalyst. Further, if the fuel supply is stopped when the fuel that is supposed to be supplied when the fuel is supplied to any combustion chamber is supplied to the combustion chamber, the amount of fuel supplied to the combustion chamber depends on the amount supplied. Since the torque is output from the internal combustion engine by that amount, it is difficult to quickly reduce the rotational speed of the internal combustion engine.

  Therefore, the present invention provides a hybrid vehicle having an internal combustion engine and two electric motors, and more appropriately controlling the internal combustion engine, thereby preventing an excess of one of the motors caused by sudden deceleration of the drive wheels without deteriorating emissions. The main purpose is to suppress rotation.

  The hybrid vehicle and the control method thereof according to the present invention employ the following means in order to achieve the main object described above.

The hybrid vehicle according to the present invention is
An internal combustion engine capable of outputting power by burning a mixture of fuel and air in a plurality of combustion chambers;
A first electric motor capable of inputting and outputting power;
A first element connected to the rotating shaft of the first electric motor; a second element connected to the output shaft of the internal combustion engine; and a third element connected to a driving shaft that transmits power to the drive wheels. A planetary gear mechanism configured such that the second element is positioned between the first element and the third element on a collinear diagram, and the three elements can be differentially rotated with respect to each other;
A second electric motor capable of inputting and outputting power to the drive shaft;
Power storage means capable of exchanging power with the first and second motors;
An allowable charging power setting means for setting an allowable charging power allowed for charging the power storage means based on the state of the power storage means;
Based on the number of rotations related to any two of the first to third elements of the planetary gear mechanism, the drive motor suddenly decelerates and the first motor connected to the first element over-rotates. Over-rotation determining means for determining whether there is a risk,
When it is determined by the over-rotation determining means that there is a risk of over-rotation of the first electric motor, fuel supply to each of the combustion chambers is stopped and input / output by the first and second electric motors. The internal combustion engine and the first and second motors are controlled so that the power to be within the range of the allowable charging power set by the allowable charging power setting means, and according to the determination result by the overspeed determination means If the fuel is supplied to at least one of the plurality of combustion chambers when the fuel supply to each of the combustion chambers should be stopped, the amount of fuel required to ignite the mixture is increased. Control means for stopping fuel supply to the at least one combustion chamber on the condition that fuel is supplied;
Is provided.

  In this hybrid vehicle, when it is determined by the over-rotation determining means that there is a risk of over-rotation of the first motor connected to the first element, the fuel supply to each of the combustion chambers is stopped and the first The internal combustion engine and the first and second motors are controlled so that the electric power input / output by the second electric motor is within the range of the allowable charging electric power allowed for charging the power storage means. And when the fuel supply to each of the combustion chambers is to be stopped according to the determination result by the over-rotation determination means in this way, when the fuel is supplied to at least one of the plurality of combustion chambers, The fuel supply to the at least one combustion chamber is stopped on condition that an amount of fuel necessary for igniting the air-fuel mixture has been supplied. Accordingly, even if the fuel supply is interrupted before the fuel to be supplied to the combustion chamber to which the fuel is supplied is supplied, the air-fuel mixture can be ignited and burned in the combustion chamber. Therefore, it is possible to suppress the deterioration of emission due to the discharge of unburned fuel. In addition, by setting the amount of fuel supplied to the combustion chamber to which fuel is supplied to an amount necessary for ignition of the air-fuel mixture, it is possible to prevent torque from being output as much as possible from the internal combustion engine, and the rotational speed of the internal combustion engine. As well as the output torque from the internal combustion engine can be reduced quickly. Therefore, in this hybrid vehicle, even if the torque output of the first and second motors is limited so as not to overcharge the power storage means, the internal combustion engine can be controlled more appropriately so that the emission of the drive wheels does not deteriorate. It is possible to suppress over-rotation of the first electric motor due to sudden deceleration.

  Further, the control means is set so that the amount necessary for igniting the air-fuel mixture increases as the intake air amount of the internal combustion engine increases and decreases as the rotational speed of the internal combustion engine increases. May be. Accordingly, it is possible to more appropriately set the fuel supply amount to the combustion chamber to which fuel is supplied when the fuel supply to each of the combustion chambers should be stopped according to the determination result by the over-rotation determination means. .

  Further, the over-rotation determination means detects that the first motor is over-rotated when the amount of decrease in the rotation speed of the third element is equal to or greater than a predetermined value and the rotation speed of the first element is equal to or greater than the predetermined rotation speed. It may be determined that there is a risk of occurrence. As a result, it is possible to more appropriately determine whether or not there is a possibility of over-rotation of the first electric motor connected to the first element.

  The power storage means may be a lithium ion secondary battery. That is, the present invention, which can suppress over-rotation of the first electric motor due to sudden deceleration of the drive wheels without deteriorating emissions by more appropriately controlling the internal combustion engine, is a lithium battery having a relatively low resistance to overcharge. It is extremely suitable for a hybrid vehicle equipped with an ion secondary battery as a power storage means.

  Further, the planetary gear mechanism holds a sun gear connected to the rotation shaft of the first electric motor, a ring gear connected to the drive shaft, and a plurality of pinion gears that mesh with both the sun gear and the ring gear. It may be a single pinion type planetary gear mechanism including a carrier connected to the output shaft of the internal combustion engine.

The hybrid vehicle control method according to the present invention includes:
An internal combustion engine capable of outputting power by burning a mixture of fuel and air in a plurality of combustion chambers, a first motor capable of inputting / outputting power, and a first element connected to a rotating shaft of the first motor And a second element connected to the output shaft of the internal combustion engine, and a third element connected to the drive shaft for transmitting power to the drive wheels, the second element on the nomograph A planetary gear mechanism that is positioned between one element and the third element and configured so that these three elements can rotate differentially with each other; and a second electric motor that can input and output power to the drive shaft; A control method for a hybrid vehicle comprising a power storage means capable of exchanging electric power with the first and second electric motors,
(A) Over-rotation of the first electric motor connected to the first element by rapid deceleration of the drive wheel based on the number of rotations related to any two of the first to third elements of the planetary gear mechanism Determining whether there is a risk of occurrence of
(B) When it is determined by the over-rotation determination means that there is a risk of over-rotation of the first electric motor, fuel supply to each of the combustion chambers is stopped and the first and second electric motors The internal combustion engine and the first and second electric motors are controlled so that the input / output power is within the allowable charging power set by the allowable charging power setting means, and the determination result by the overspeed determination means Required to ignite the air-fuel mixture if the fuel is supplied to at least one of the plurality of combustion chambers when the fuel supply to each of the combustion chambers should be stopped according to Stopping fuel supply to the at least one combustion chamber on the condition that a sufficient amount of fuel has been supplied;
Is included.

  According to this method, when the fuel supply to each of the combustion chambers should be stopped according to the determination result by the over-rotation determination means, the amount of fuel that should be supplied to the combustion chamber to which the fuel is supplied is supplied. Even if the fuel supply is interrupted before being performed, the air-fuel mixture can be ignited and combusted in the combustion chamber, so that it is possible to suppress the deterioration of emissions due to the discharge of unburned fuel. In addition, by setting the amount of fuel supplied to the combustion chamber to which fuel is supplied to an amount necessary for ignition of the air-fuel mixture, it is possible to prevent torque from being output as much as possible from the internal combustion engine, and the rotational speed of the internal combustion engine. As well as the output torque from the internal combustion engine can be reduced quickly. Therefore, if this method is adopted, even if the torque output of the first and second motors is limited so that the power storage means is not overcharged, the internal combustion engine can be controlled more appropriately to drive without deteriorating emissions. It is possible to suppress over-rotation of the first electric motor due to the sudden deceleration of the wheel.

  Next, the best mode for carrying out the present invention will be described using examples.

  FIG. 1 is a schematic configuration diagram of a hybrid vehicle 20 according to an embodiment of the present invention. A hybrid vehicle 20 shown in FIG. 1 includes an internal combustion engine device 21 including an engine 22, a three-shaft power distribution and integration mechanism 30 connected to a crankshaft 26 that is an output shaft of the engine 22 via a damper 28, A motor MG1 capable of generating electricity connected to the distribution integration mechanism 30, a reduction gear 35 connected to a ring gear shaft 32a as a drive shaft connected to the power distribution integration mechanism 30, and a ring gear shaft 32a via the reduction gear 35 And a hybrid electronic control unit (hereinafter referred to as “hybrid ECU”) 70 for controlling the entire hybrid vehicle 20 and the like.

  The engine 22 constituting the internal combustion engine device 21 explosively burns a mixture of hydrocarbon fuels such as gasoline and light oil and air in a plurality of (in the embodiment, four cylinders) combustion chambers 120, and the mixture is exploded. The internal combustion engine is configured to output power by converting the reciprocating motion of the piston 121 accompanying the combustion into the rotational motion of the crankshaft 26. In this engine 22, as can be seen from FIG. 2, the air purified by the air cleaner 122 is taken into the intake pipe 126 through the throttle valve 123, and fuel such as gasoline is injected from the fuel injection valve 127 into the intake air. The The mixture of air and fuel thus obtained is sucked into the combustion chamber 120 through an intake valve 131 driven by a valve operating mechanism 130 configured as a variable valve timing mechanism, and explodes by an electric spark from the spark plug 128. Burned. The exhaust gas from the engine 22 is an exhaust gas purification catalyst (three-way catalyst) that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) through the exhaust valve 132 and the exhaust manifold 140. ) And is purified by the purification device 141 and then discharged to the outside. The internal combustion engine device 21 is connected to an exhaust pipe downstream of the purification device 141 and recirculates exhaust gas to a surge tank (intake system), and is provided in the middle of the EGR pipe 142 and is connected to the exhaust system. An EGR valve 143 that adjusts the recirculation amount (EGR amount) of exhaust gas (EGR gas) recirculated to the intake system, a temperature sensor 144 that detects the temperature of the EGR gas in the EGR pipe 142, and the like are included.

  The engine 22 configured in this way is controlled by an engine electronic control unit (hereinafter referred to as “engine ECU”) 24. As shown in FIG. 2, the engine ECU 24 is configured as a microprocessor centered on a CPU 24a. In addition to the CPU 24a, a ROM 24b that stores various processing programs, a RAM 24c that temporarily stores data, and an input (not shown). Output port and communication port. Then, signals from various sensors that detect the state of the engine 22 and the like are input to the engine ECU 24 via an input port (not shown). For example, the engine ECU 24 includes a crank position from a crank position sensor 180 that detects the rotational position of the crankshaft 26, a cooling water temperature Tw from a water temperature sensor 181 that detects the temperature of cooling water in the engine 22, and a pressure in the combustion chamber 120. A cylinder position from a cylinder pressure sensor 182 that detects the rotational position of a camshaft included in a valve operating mechanism 130 that drives the intake valve 131 and the exhaust valve 132; The throttle position from the throttle valve position sensor 124 for detecting the position of the engine, the intake air amount GA from the air flow meter 183 for detecting the intake air amount as a load of the engine 22, and the intake air temperature sensor 184 attached to the intake pipe 126 Intake air temperature Air, intake negative pressure Pi from the intake pressure sensor 185 for detecting the negative pressure in the intake pipe 126, air-fuel ratio AF from the air-fuel ratio sensor 186 disposed upstream of the purification device 141 of the exhaust manifold 140, EGR pipe 142 The EGR gas temperature from the temperature sensor 144 is input via the input port. The engine ECU 24 outputs various control signals for driving the engine 22 through an output port (not shown). For example, the engine ECU 24 sends a drive signal to the fuel injection valve 127, a drive signal to the throttle motor 125 that adjusts the position of the throttle valve 123, a control signal to the ignition coil 129 integrated with the igniter, and the valve mechanism 130. Control signal, a drive signal to the EGR valve 143, and the like are output via an output port. Further, the engine ECU 24 is in communication with the hybrid ECU 70, controls the operation of the engine 22 by a control signal from the hybrid ECU 70, and outputs data related to the operation state of the engine 22 to the hybrid ECU 70 as necessary.

  The power distribution and integration mechanism 30 includes an external gear sun gear 31, an internal gear ring gear 32 disposed concentrically with the sun gear 31, a plurality of pinion gears 33 that mesh with the sun gear 31 and mesh with the ring gear 32, And a carrier 34 that holds the plurality of pinion gears 33 so as to rotate and revolve. The carrier 34 is positioned between the sun gear 31 and the ring gear 32 on the collinear diagram, and these three elements can rotate differentially with respect to each other. A single pinion type planetary gear mechanism configured as described above. The sun gear 31 that is the first element of the power distribution and integration mechanism 30 has the rotation shaft of the motor MG1, the carrier that is the second element is the crankshaft 26 of the engine 22, and the ring gear 32 that is the third element is the ring gear shaft. The rotational shafts of the motor MG2 are connected to each other through 32a and the reduction gear 35. The power distribution and integration mechanism 30 distributes the power from the engine 22 input from the carrier 34 to the sun gear 31 side and the ring gear 32 side according to the gear ratio when the motor MG1 functions as a generator. , The power from the engine 22 input from the carrier 34 and the power from the motor MG1 input from the sun gear 31 are integrated and output to the ring gear 32 side. The power output to the ring gear 32 is finally output from the ring gear shaft 32a to the wheels 39a and 39b, which are drive wheels, via the gear mechanism 37 and the differential gear 38.

  Each of the motors MG1 and MG2 is configured as a well-known synchronous generator motor that operates as a generator and can operate as an electric motor, and exchanges power with a battery 50 that is a secondary battery via inverters 41 and 42. . The power line 54 connecting the inverters 41 and 42 and the battery 50 is configured as a positive bus and a negative bus shared by the inverters 41 and 42, and the power generated by one of the motors MG1 and MG2 is used as the other. It can be consumed with the motor. Therefore, the battery 50 is charged / discharged by electric power generated from one of the motors MG1 and MG2 or insufficient electric power. If the electric power balance is balanced by the motors MG1 and MG2, the battery 50 is charged. It will not be discharged. The motors MG1 and MG2 are both driven and controlled by a motor electronic control unit (hereinafter referred to as “motor ECU”) 40. The motor ECU 40 receives signals necessary for driving and controlling the motors MG1 and MG2, such as signals from rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2, and current sensors (not shown). The detected phase current applied to the motors MG1 and MG2 and the like are input, and the motor ECU 40 outputs a switching control signal and the like to the inverters 41 and 42. Further, the motor ECU 40 executes a rotation speed calculation routine (not shown) based on signals input from the rotation position detection sensors 43 and 44, and calculates the rotation speeds Nm1 and Nm2 of the rotors of the motors MG1 and MG2. Further, the motor ECU 40 communicates with the hybrid ECU 70, controls the driving of the motors MG1, MG2 based on the control signal from the hybrid ECU 70, and transmits data related to the operating state of the motors MG1, MG2 to the hybrid ECU 70 as necessary. Output.

  The battery 50 is configured as a lithium ion secondary battery or a nickel hydride secondary battery, and is managed by a battery electronic control unit (hereinafter referred to as “battery ECU”) 52. The battery ECU 52 receives signals necessary for managing the battery 50, for example, a voltage between terminals from a voltage sensor (not shown) installed between the terminals of the battery 50, and a power line 54 connected to the output terminal of the battery 50. A charging / discharging current from an attached current sensor (not shown), a battery temperature Tb from a temperature sensor 51 attached to the battery 50, and the like are input. The battery ECU 52 outputs data related to the state of the battery 50 to the hybrid ECU 70 by communication as necessary. Further, in order to manage the battery 50, the battery ECU 52 calculates the remaining capacity SOC based on the integrated value of the charging / discharging current detected by the current sensor, or requests charging / discharging of the battery 50 based on the remaining capacity SOC. The power Pb * is calculated, or the input limit Win as the allowable charging power, which is the power allowed for charging the battery 50 based on the remaining capacity SOC and the battery temperature Tb, and the power allowed for discharging the battery 50. The output limit Wout as the allowable discharge power is calculated. The input / output limits Win and Wout of the battery 50 set basic values of the input / output limits Win and Wout based on the battery temperature Tb, and output correction correction coefficients based on the remaining capacity (SOC) of the battery 50. It can be set by setting a correction coefficient for input restriction and multiplying the basic value of the set input / output restrictions Win and Wout by the correction coefficient.

  The hybrid ECU 70 is configured as a microprocessor centered on the CPU 72, and includes a ROM 74 for storing a processing program, a RAM 76 for temporarily storing data, an input / output port and a communication port (not shown), and the like in addition to the CPU 72. The hybrid ECU 70 detects the ignition signal from the ignition switch (start switch) 80, the shift position SP from the shift position sensor 82 that detects the shift position SP that is the operation position of the shift lever 81, and the depression amount of the accelerator pedal 83. The accelerator opening Acc from the accelerator pedal position sensor 84, the brake pedal stroke BS from the brake pedal stroke sensor 86 for detecting the depression amount of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 87, and the like are input via the input port. . As described above, the hybrid ECU 70 is connected to the engine ECU 24, the motor ECU 40, the battery ECU 52, etc. via the communication port, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, the battery ECU 52, etc. ing.

  In the hybrid vehicle 20 of the embodiment configured as described above, the hybrid ECU 70 applies the wheels 39a and 39b, which are drive wheels, to the drive wheels based on the accelerator opening Acc and the vehicle speed V corresponding to the depression amount of the accelerator pedal 83 by the driver. The required torque Tr * to be output to the ring gear shaft 32a serving as the connected drive shaft is calculated, and the engine 22 is output by the engine ECU 24 and the motor ECU 40 so that the torque based on the required torque Tr * is output to the ring gear shaft 32a. Motors MG1 and MG2 are respectively controlled. As the operation control mode of the engine 22 and the motors MG1 and MG2, the operation of the engine 22 is controlled so that the power corresponding to the required torque Tr * is output from the engine 22, and all the power output from the engine 22 is power distribution integrated. Torque conversion operation mode for driving and controlling the motors MG1 and MG2 so that the torque is converted by the mechanism 30 and the motors MG1 and MG2 and output to the ring gear shaft 32a, the required torque Tr * and the power required for charging and discharging the battery 50 The engine 22 is operated and controlled so that the power corresponding to the sum of the power is output from the engine 22, and all or part of the power output from the engine 22 with charging / discharging of the battery 50 is the power distribution integration mechanism 30 and the motor. Requested with torque conversion by MG1 and MG2. The charge / discharge operation mode for driving and controlling the motors MG1 and MG2 so that the torque based on the torque Tr * is output to the ring gear shaft 32a, and the operation of the engine 22 is stopped and the torque based on the required torque Tr * is output to the ring gear shaft 32a. Thus, there is a motor operation mode for driving and controlling the motor MG2.

  Next, the operation when the hybrid vehicle 20 of the embodiment configured as described above is traveling will be described. FIG. 3 is a flowchart illustrating an example of a drive control routine that is executed at predetermined time intervals (for example, every several milliseconds) by the hybrid ECU 70 of the embodiment when the hybrid vehicle 20 is traveling with the operation of the engine 22. It is.

  At the start of the drive control routine shown in FIG. 3, the CPU 72 of the hybrid ECU 70 determines the accelerator opening Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 87, the rotational speed Ne of the engine 22, and the motors MG1 and MG2. Input processing of data necessary for control such as the rotation speed Nm1, Nm2, charge / discharge required power Pb *, input / output limits Win and Wout of the battery 50, and the value of the overspeed prediction flag Fer is executed (step S100). Here, the rotational speed Ne of the engine 22 is calculated by the engine ECU 24 based on the crank position from the crank position sensor 180 and is input from the engine ECU 24 by communication. Further, the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 are input from the motor ECU 40 through communication, and the charge / discharge request power Pb * and the input / output limits Win and Wout are input from the battery ECU 52 through communication. It is. Further, the over-rotation prediction flag Fer is normally set to a value of 0, and the wheels 39a and 39b, the ring gear 32, and the like due to the recovery of the grip force after the slip of the wheels 39a and 39b, which are drive wheels, for example, occur. When the motor MG1 connected to the sun gear 31 of the power distribution and integration mechanism 30 may over-rotate due to sudden deceleration of the motor MG2, the hybrid ECU 70 sets the value to 1 as described later.

  After the data input process of step S100, it is determined whether or not the overspeed prediction flag Fer is 0 (step S110). When the overspeed prediction flag Fer has a value of 0, the rotational speed change amount is obtained by subtracting the rotational speed Nm2 (previous Nm2) input at the previous execution of this routine from the rotational speed Nm2 of the motor MG2 input at step S100. ΔNm2 is calculated (step S120), and whether or not the rotational speed change amount ΔNm2 is less than a predetermined negative threshold value ΔNref, that is, whether or not the decrease amount of the rotational speed Nm2 of the motor MG2 is greater than or equal to the value | ΔNref | Is determined (step S130). The threshold value ΔNref may be a fixed value, for example, a variable value that is set to be smaller (the absolute value is larger) as the vehicle speed V is higher. When it is determined in step S130 that the rotation speed change amount ΔNm2 is equal to or greater than the threshold value ΔNref, the overspeed prediction flag Fer is set to a value 0 on the assumption that there is no possibility that the motor MG1 will overspeed (step S150). ) When the engine ECU 24 is requested to stop fuel injection into each combustion chamber 120 (hereinafter referred to as “fuel cut” as appropriate), the fuel cut request flag Ffcd set to 1 is set to 0 (see FIG. Step S160). If it is determined in step S130 that the rotational speed change amount ΔNm2 is less than the threshold value ΔNref, the rotational speed Nm1 of the motor MG1 input in step S100 is a positive value determined in advance. It is determined whether or not the rotational speed is less than Nm1ref (step S140). If the rotational speed Nm1 is less than the determination rotational speed Nm1ref, the rotational flag Fer is set to 0 (step S150) and the fuel is cut. The request flag Ffcd is set to 0 (step S160). Note that the determination rotational speed Nm1ref is a relatively large value lower than the normal maximum rotational speed of the motor MG1.

  When the fuel cut request flag Ffcd is set to a value of 0 in step S160, the ring gear shaft connected to the wheels 39a and 39b as drive wheels based on the accelerator opening Acc and the vehicle speed V input in step S100. After setting the required torque Tr * to be output to 32a, the required power Pe * required for the engine 22 is set (step S170). In the embodiment, the relationship among the accelerator opening Acc, the vehicle speed V, and the required torque Tr * is determined in advance and stored in the ROM 74 as a required torque setting map. The required torque Tr * is the given accelerator opening. The one corresponding to Acc and the vehicle speed V is derived and set from the map. FIG. 4 shows an example of the required torque setting map. In the embodiment, the required power Pe * is calculated as a sum of the set required torque Tr * multiplied by the rotation speed Nr of the ring gear shaft 32a, the charge / discharge required power Pb *, and the loss Loss. The rotational speed Nr of the ring gear shaft 32a can be obtained by dividing the rotational speed Nm2 of the motor MG2 by the gear ratio Gr of the reduction gear 35 as shown in the figure or by multiplying the vehicle speed V by the conversion factor k. Next, a target rotational speed Ne * and a target torque Te *, which are target operating points of the engine 22, are set based on the required power Pe * and transmitted to the engine ECU 24 (step S180). In the embodiment, the target rotational speed Ne * and the target torque Te * of the engine 22 are set based on a predetermined operation line and the required power Pe * in order to operate the engine 22 efficiently. FIG. 5 illustrates an operation line of the engine 22 and a correlation curve between the rotational speed Ne and the torque Te indicating that the required power Pe * is constant. As shown in the figure, the target rotational speed Ne * and the target torque Te * can be obtained as an intersection of the operation line and a correlation curve indicating that the required power Pe * (Ne * × Te *) is constant. it can. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * from the hybrid ECU 70 sets the target intake air amount GA * based on the target rotational speed Ne * and the target torque Te *, and also sets the target intake air amount GA. The target opening Th * of the throttle valve 123 is set based on *, and the throttle motor 125 is controlled based on the throttle position from the throttle valve position sensor 124 so that the opening of the throttle valve 123 becomes the target opening Th *. To do. Further, the engine ECU 24 executes fuel injection control, ignition timing control, valve timing control, exhaust gas recirculation control, and the like in addition to such throttle opening degree control.

  After setting the target rotational speed Ne * and the target torque Te * of the engine 22, the target rotational speed Ne *, the rotational speed of the ring gear shaft 32a (Nm2 / Gr), and the gear ratio ρ of the power distribution and integration mechanism 30 (the teeth of the sun gear 31) Number / the number of teeth of the ring gear 32) and the target rotational speed Nm1 * of the motor MG1 is calculated according to the following formula (1), and the following formula based on the calculated target rotational speed Nm1 * and the current rotational speed Nm1 The calculation of (2) is executed to calculate a temporary motor torque Tm1tmp, which is a temporary value of torque to be output from the motor MG1 (step S190). Here, Expression (1) is a dynamic relational expression for the rotating element of the power distribution and integration mechanism 30. FIG. 6 illustrates a collinear diagram showing a dynamic relationship between the number of rotations and torque in the rotating elements of the power distribution and integration mechanism 30. In the figure, the left S-axis indicates the rotational speed of the sun gear 31 that matches the rotational speed Nm1 of the motor MG1, the central C-axis indicates the rotational speed of the carrier 34 that matches the rotational speed Ne of the engine 22, and the right R-axis. The axis indicates the rotational speed Nr of the ring gear 32 obtained by dividing the rotational speed Nm2 of the motor MG2 by the gear ratio Gr of the reduction gear 35. The two thick arrows on the R axis indicate the torque acting on the ring gear shaft 32a by this torque output when the motor MG1 outputs the torque Tm1, and the reduction gear 35 when the motor MG2 outputs the torque Tm2. And the torque acting on the ring gear shaft 32a via. Expression (1) for obtaining the target rotational speed Nm1 * of the motor MG1 can be easily derived by using the rotational speed relationship in this alignment chart. Expression (2) is a relational expression in feedback control for rotating the motor MG1 at the target rotational speed Nm1 *. In Expression (2), “k1” in the second term on the right side is a gain of the proportional term. “K2” in the third term on the right side is the gain of the integral term.

Nm1 * = Ne * ・ (1 + ρ) / ρ-Nm2 / (Gr ・ ρ) (1)
Tm1tmp = -ρ / (1 + ρ) ・ Te * + k1 ・ (Nm1 * -Nm1) + k2 ・ ∫ (Nm1 * -Nm1) dt (2)

  Subsequently, torque limits Tm1min and Tm1max are set as upper and lower limits of the torque that may be output from the motor MG1 so as to satisfy both the following expressions (3) and (4) (step S200), and a torque command for the motor MG1 is set. Tm1 * is set to a value obtained by limiting the temporary motor torque Tm1tmp with the torque limits Tm1min and Tm1max (step S210). Here, Expression (3) is a relational expression indicating that the total torque output to the ring gear shaft 32a by the motor MG1 and the motor MG2 is included in the range from the value 0 to the required torque Tr *. (4) is a relational expression indicating that the sum of the electric power input and output by the motor MG1 and the motor MG2 is included in the range of the input / output limits Win and Wout. The relationship shown in these equations (3) and (4) is illustrated in FIG. As can be seen from the figure, the torque limits Tm1min and Tm1max can be obtained as the maximum / minimum value of the torque Tm1 in the region indicated by the oblique lines in the figure. As a result, if the torque command Tm1 * for the motor MG1 is a value obtained by limiting the temporary motor torque Tm1tmp with the torque limits Tm1min and Tm1max, the power (generated power) input / output by the motor MG1 is set to the input / output limit Win of the battery 50. It can be within the range.

0 ≦ -Tm1 / ρ + Tm2, Gr ≦ Tr * (3)
Win ≦ Tm1 / Nm1 + Tm2 / Nm2 ≦ Wout… (4)

  If the torque command Tm1 * for the motor MG1 is set, it should be output from the motor MG2 using the required torque Tr *, the torque command Tm1 *, the gear ratio ρ of the power distribution and integration mechanism 30, and the gear ratio Gr of the reduction gear 35. A temporary motor torque Tm2tmp, which is a temporary value of torque, is calculated according to the following equation (5) (step S220). Further, output from motor MG2 may be performed using input / output limits Win and Wout of battery 50, torque command Tm1 * for motor MG1 set in step S210, and current rotation speeds Nm1 and Nm2 of motors MG1 and MG2. Torque limits Tm2min and Tm2max as upper and lower torque limits are calculated according to the following equations (6) and (7) (step S230). Then, the torque command Tm2 * for the motor MG2 is set to a value obtained by limiting the temporary motor torque Tm2tmp with the torque limits Tm2min and Tm2max (step S240). By setting the torque command Tm2 * for the motor MG2 in this manner, the torque output to the ring gear shaft 32a can be set as a torque that is limited within the range of the input / output limits Win and Wout of the battery 50. Equation (5) can be easily derived from the alignment chart of FIG. When torque commands Tm1 * and Tm2 * for motors MG1 and MG2 are set in this way, torque commands Tm1 * and Tm2 * are transmitted to motor ECU 40 (step S250), and the processing from step S100 is executed again. The motor ECU 40 that has received the torque commands Tm1 * and Tm2 * switches the switching elements of the inverters 41 and 42 so that the motor MG1 is driven according to the torque command Tm1 * and the motor MG2 is driven according to the torque command Tm2 *. Take control.

Tm2tmp = (Tr * + Tm1 * / ρ) / Gr (5)
Tm2min = (Win-Tm1 * ・ Nm1) / Nm2 (6)
Tm2max = (Wout-Tm1 * ・ Nm1) / Nm2 (7)

  On the other hand, if it is determined in step S130 that the rotational speed change amount ΔNm2 is less than the threshold value ΔNref and it is determined in step S140 that the rotational speed Nm1 is greater than or equal to the determination rotational speed Nm1ref, FIG. As indicated by the broken line, it is considered that the motor MG1 connected to the sun gear 31 may over-rotate due to sudden deceleration of the wheels 39a, 39b, the ring gear 32, and the motor MG2, and the above-described over-rotation prediction flag Fer is set to a value of 1. At the same time (step S270), the fuel cut request flag Ffcd is set to a value 1 to request the engine ECU 24 to stop fuel injection to the engine 22 (step S280). Then, the rotation input in step S100 from a torque command setting map (not shown) prepared in advance so as to prescribe the relationship between the rotational speed Ne of the engine 22 and the temporary motor torque Tm1tmp, giving priority to suppression of excessive rotation of the motor MG1. The temporary motor torque Tm1tmp corresponding to the number Ne is derived and set (step S290), and the processes in steps S200 to S250 are performed, and then the processes in and after step S100 are performed again. That is, when there is a possibility that the motor MG1 may over-rotate due to sudden deceleration of the wheels 39a, 39b, the ring gear 32, and the motor MG2, the fuel injection into each combustion chamber 120 of the engine 22 is stopped (step S280). As indicated by a two-dot chain line in FIG. 6, the rotational speed Ne of the engine 22 is quickly reduced and the output torque of the engine 22 is rapidly reduced, thereby suppressing the rotational increase of the motor MG1 and by the motors MG1 and MG2. Motors MG1 and MG2 are controlled so that the input / output power is within the range of input / output limits Win and Wout of battery 50 (steps S290, S200 to S250). Note that after the overspeed prediction flag F is once set to the value 1 in step S280, a negative determination is made in step S110. In this case, the rotation of the engine 22 input in step S100 is determined. It is determined whether or not the number Ne is equal to or higher than a predetermined determination rotational speed Neref as a value that is low enough not to cause over-rotation of the motor MG1 (step S260), and the rotational speed Ne is equal to or higher than the determination rotational speed Neref. If there is, the processes of steps S280 and S200 to S250 are executed. If it is determined in step S260 that the rotation speed Ne is less than the determination rotation speed Neref, the processes in steps S150 to S250 are executed again.

  Next, the operation when the hybrid ECU 70 makes a fuel cut request to the engine ECU 24 will be described. FIG. 8 is a flowchart showing an example of a fuel cut time control routine executed by the engine ECU 24 when the fuel cut request flag Ffcd is set to a value 1 by the hybrid ECU 70.

  At the start of the fuel cut time control routine of FIG. 8, the CPU 24a of the engine ECU 24 determines whether or not there is a fuel injection valve 127 that is injecting fuel at that time based on, for example, the fuel injection end timing of each fuel injection valve 127 or the like. Determination is made (step S310). If there is no fuel injection valve 127 during fuel injection, the fuel injection from all the fuel injection valves 127 is prohibited until a command to stop the fuel cut is issued thereafter. The cut flag Ffc is set to 1 (step S400), and this routine is terminated. On the other hand, if it is determined in step S310 that there is a fuel injection valve 127 during fuel injection, fuel injection from all the fuel injection valves 127 that are not injecting fuel at that time is prohibited. (Step S320), for example, the earliest (earliest) of the fuel injection valves 127 that are injecting fuel based on the fuel injection end timing of each fuel injection valve 127 is identified. (Step S330). Next, the rotational speed Ne of the engine 22 and the intake air amount GA from the air flow meter 183 are input (step S340), and the minimum amount of fuel necessary for igniting the mixture of fuel and air in the combustion chamber 120. Is set based on the rotational speed Ne and the intake air amount GA (step S350). In the embodiment, the relationship among the rotational speed Ne, the intake air amount GA, and the minimum injection amount Qmin is determined in advance based on the experiment and analysis results, and is stored in the ROM 24b as a minimum injection amount setting map. Are derived and set from the map corresponding to the given rotational speed Ne and intake air amount GA. FIG. 9 shows an example of the minimum injection amount setting map. As shown in the figure, the minimum injection amount setting map of the embodiment increases the minimum injection amount Qmin as the intake air amount GA increases, and decreases the minimum injection amount Qmin as the rotational speed Ne of the engine 22 increases. Has been created.

  Thus, when the minimum injection amount Qmin is set, the time required to inject the fuel by the minimum injection amount Qmin into the combustion chamber 120 is determined as the minimum injection time τmin (step S360), and the fuel injection is performed at the earliest target. The injection time τ measured with respect to the fuel injection valve 127 during the fuel injection that ends is compared with the minimum injection time τmin (step S370). When it is determined that the injection time τ is equal to or longer than the minimum injection time τmin when the process of step S370 is executed once, the fuel injection from the target fuel injection valve 127 is stopped at that time, and A control signal is transmitted to the ignition coil 129 of the spark plug 128 disposed in the combustion chamber 120 so that the air-fuel mixture is ignited in the combustion chamber 120 corresponding to the fuel injection valve 127 (step S380). When it is determined that the injection time τ is less than the minimum injection time τmin when the process of step S370 is executed once, the fuel injection is continued until the injection time τ reaches the minimum injection time τmin, When the injection time τ becomes equal to or longer than the minimum injection time τmin, fuel injection from the target fuel injection valve 127 is stopped, and ignition of the air-fuel mixture in the combustion chamber 120 corresponding to the fuel injection valve 127 is executed. (Step S380). After the process of step S380, it is determined whether or not the fuel injection to all the combustion chambers 120 has been stopped (step S390). If there are other fuel injection valves 127 during the fuel injection, the processes of steps S330 to S380 are performed again. Execute the process. Then, when the fuel injection from all the fuel injection valves 127 is stopped, the fuel injection from all the fuel injection valves 127 is prohibited until a command to stop the fuel cut is issued thereafter. Then, the fuel cut flag Ffc is set to 1 (step S400), and this routine is terminated.

  FIG. 10 is a time chart illustrating how the fuel injection control routine is executed and fuel injection into each combustion chamber 120 is stopped. In FIG. 10, a solid double arrow indicates that fuel injection is being performed, and a dotted double arrow or arrow indicates that fuel injection is not being performed. In the example shown in the figure, when the hybrid ECU 70 determines that the fuel cut request flag Ffcd is set to a value 1 (time t0), the third (# 3) and fourth (# 4) combustion chambers 120 enter the combustion chamber 120. On the other hand, since the fuel is not injected from the fuel injection valve 127, fuel injection into the third and fourth combustion chambers 120 is prohibited at that time (step S320 in FIG. 8). In the example of FIG. 10, fuel is injected from the fuel injection valve 127 into the first (# 1) and second (# 2) combustion chambers 120 at time t0. Since the injection time τ exceeds the above-mentioned minimum injection time τmin, the fuel injection is stopped and the air-fuel mixture at the time (time t0) when it is determined that the fuel cut request flag Ffcd is set to the value 1. Is executed (steps S370 and S380 in FIG. 8). For the first combustion chamber 120, the injection time τ is less than the above-mentioned minimum injection time τmin when it is determined that the fuel cut request flag Ffcd is set to the value 1 (time t0). Fuel injection is continued until the injection time τ reaches the minimum injection time τmin. For the first combustion chamber 120, the fuel injection is stopped and the air-fuel mixture is ignited when the injection time τ reaches the minimum injection time τmin (time t1) (steps S370 and S380 in FIG. 8). At the same time, the fuel cut flag Ffc is set to 1 (step S400 in FIG. 8).

  As described above, in the hybrid vehicle 20 of the embodiment, when it is determined by the hybrid ECU 70 that there is a risk of over-rotation of the motor MG1 connected to the sun gear 31 due to sudden deceleration of the wheels 39a and 39b. (Steps S130 and S140), the fuel injection to each of the combustion chambers 120 is stopped, and the power that is input and output by the motors MG1 and MG2 is within the range of the input limit Win as the allowable charging power that is allowed to charge the battery 50. The engine 22 and the motors MG1 and MG2 are controlled so as to be within (steps S270 to 290, S200 to S250 in FIG. 3). Then, when it is determined that there is a possibility of over-rotation of the motor MG1 in this way, when fuel injection to each of the combustion chambers 120 should be stopped, at least one of the plurality of combustion chambers 120 When the fuel is injected into the at least one combustion chamber 120, the fuel injection is stopped on the condition that the fuel of the minimum injection amount Qmin necessary for igniting the air-fuel mixture is supplied (see FIG. 8 steps S330 to S380).

  As a result, even if fuel injection is interrupted before the amount of fuel that should be supplied to the combustion chamber 120 into which fuel is being injected is injected, the air-fuel mixture is ignited and burned in the combustion chamber 120. Therefore, it is possible to suppress the deterioration of emission due to the discharge of unburned fuel. In addition, by setting the fuel injection amount into the combustion chamber 120 into which fuel is injected to the minimum injection amount Qmin necessary for ignition of the air-fuel mixture, it is possible to prevent torque from being output from the engine 22 as much as possible. The rotational speed Ne of the engine 22 can be quickly reduced, and the output torque from the engine 22 can be quickly reduced. Therefore, in the hybrid vehicle 20 of the embodiment, even if the torque output of the motors MG1 and MG2 is limited so as not to overcharge the battery 50 (steps S200 to S250 in FIG. 3), the engine 22 is controlled more appropriately. Thus, it is possible to suppress over-rotation of the motor MG1 due to the rapid deceleration of the wheels 39a and 39b as drive wheels without deteriorating the emission.

  Further, in the hybrid vehicle 20 of the embodiment, the minimum injection amount Qmin necessary for igniting the air-fuel mixture increases as the intake air amount GA of the engine 22 increases, and decreases as the engine speed Ne increases. It is set (see FIG. 9). As a result, the fuel injection amount into the combustion chamber 120 into which fuel is injected when it is determined that there is a risk of over-rotation of the motor MG1 and fuel injection to each of the combustion chambers 120 should be stopped. Can be set more appropriately. Further, as in the above embodiment, the rotational speed change amount ΔNm2 of the rotational speed Nm2 of the motor MG2 proportional to the rotational speed of the ring gear 32 is less than the negative threshold value ΔNref, that is, the amount of decrease in the rotational speed Nm2 of the motor MG2 is the value | ΔNref | If it is determined that there is a possibility of over-rotation of the motor MG1 when the rotation speed Nm1 of the motor MG1 equal to the rotation speed of the sun gear 31 is equal to or higher than the determination rotation speed Nm1ref, the over-rotation of the motor MG1 It is possible to more appropriately determine whether or not there is a possibility of occurrence of the above. As described above, it is possible to suppress over-rotation of the motor MG1 due to sudden deceleration of the wheels 39a and 39b that are drive wheels without deteriorating emissions by controlling the engine 22 more appropriately. In adopting a lithium ion secondary battery having high density, small size and light weight as well as relatively low resistance to overcharge as the battery 50, it is extremely advantageous from the viewpoint of protecting the battery 50.

  Although the suppression of over-rotation of the motor MG1 due to the recovery of the grip force after the slip of the wheels 39a and 39b, which are drive wheels, has been described so far, such over-rotation of the motor MG1 is This may occur due to sudden deceleration (locking) of the wheels 39a and 39b as drive wheels due to sudden braking while the hybrid vehicle 20 is traveling. Therefore, the fuel cut time control routine of FIG. 8 may be executed at the time of fuel cut of the engine 22 accompanying sudden braking (and accelerator off) of the hybrid vehicle 20. As a result, when the wheels 39a and 39b, which are drive wheels, are suddenly decelerated or locked due to sudden braking, the rotational speed Ne of the engine 22 is rapidly reduced and output torque from the engine 22 is not deteriorated. Can be quickly reduced, thereby making it possible to satisfactorily suppress over-rotation of the motor MG1. Furthermore, in the hybrid vehicle 20 of the above-described embodiment, the ring gear shaft 32a as the drive shaft and the motor MG2 are connected via the reduction gear 35 that reduces the rotational speed of the motor MG2 and transmits it to the ring gear shaft 32a. Instead of the reduction gear 35, for example, a transmission that shifts the rotational speed of the motor MG2 having two shift stages of Hi and Lo or three or more shift stages and transmits it to the ring gear shaft 32a may be employed. . Moreover, although the hybrid vehicle 20 of an Example outputs the motive power of motor MG2 to the ring gear shaft 32a as a drive shaft, the application object of this invention is not restricted to this. That is, the present invention outputs the power of the motor MG2 to an axle different from the ring gear shaft 32a (an axle connected to the wheels 39c and 39d in FIG. 11) as in the hybrid vehicle 20A according to the modification shown in FIG. It may be applied to things.

  Here, the correspondence between the main elements of the above-described embodiments and modifications and the main elements of the invention described in the column of means for solving the problems will be described. That is, in the above-described embodiments, the engine 22 capable of outputting power by burning a mixture of fuel and air in the plurality of combustion chambers 120 corresponds to an “internal combustion engine”, and a motor MG1 capable of inputting and outputting power. Corresponds to the first electric motor and is connected to the sun gear 31 connected to the motor MG1, the carrier 34 connected to the crankshaft 26 of the engine 22, and the ring gear shaft 32a for transmitting power to the wheels 39a and 39b as drive wheels. The power distribution and integration mechanism 30 is configured such that the carrier 34 is positioned between the sun gear 31 and the ring gear 32 on the collinear diagram, and these three elements can be differentially rotated with respect to each other. Corresponds to the “planetary gear mechanism”, the motor MG2 capable of inputting / outputting power to / from the ring gear shaft 32a corresponds to the “motor”, and the motor MG1 and the motor MG The battery 50 that can exchange electric power with the battery 50 corresponds to “power storage means”, the battery ECU 52 that sets the input limit Win of the battery 50 corresponds to “allowable charging power setting means”, and the rotation of the sun gear 31 of the power distribution integration mechanism 30 Of the motor MG1 connected to the sun gear 31 by sudden deceleration of the wheels 39a and 39b as drive wheels based on the number of rotations Nm1 of the motor MG1 corresponding to the number and the number of rotations Nm2 of the motor MG2 proportional to the number of rotations of the ring gear 32. The hybrid ECU 70 that determines whether or not there is a possibility of over-rotation corresponds to “over-rotation determination means”. The hybrid ECU 70 that executes the drive control routine of FIG. 3, the target rotational speed Ne * from the hybrid ECU 70, and The engine 22 is controlled in accordance with the target torque Te * and the fuel cut control loop of FIG. An engine ECU24 for executing down, a combination of a motor ECU40 for controlling the motors MG1 and MG2 in accordance with torque command Tm1 * and Tm2 * from the hybrid ECU70 corresponds to the "control means".

  However, the “internal combustion engine” is not limited to the engine 22 that outputs power by receiving a hydrocarbon-based fuel such as gasoline or light oil, and may be of any other type such as a hydrogen engine. The “first motor” and the “second motor” are not limited to the synchronous generator motors such as the motors MG1 and MG2, and may be any other type such as an induction motor. The “planetary gear mechanism” is a first element connected to the rotation shaft of the first motor, a second element connected to the output shaft of the internal combustion engine, and a first shaft connected to the drive shaft that transmits power to the drive wheels. 3 elements, and the second element is positioned between the first element and the third element on the collinear diagram, and these three elements are configured to be capable of differential rotation with respect to each other. Any format is acceptable. The “storage means” is not limited to the secondary battery such as the battery 50, and may be any other type such as a capacitor as long as it can exchange power with the first and second motors. . The “allowable charging power setting means” is of any type other than the battery ECU 52 as long as it sets the allowable charging power allowed for charging the power storage means based on the state of the power storage means. It doesn't matter. Is the “overspeed determination means” likely to cause overspeed of the first electric motor due to sudden deceleration of the drive wheel based on the speed related to any two of the first to third elements of the planetary gear mechanism? Any type other than the hybrid ECU 70 may be used as long as the determination is made. When it is determined that there is a risk of over-rotation of the first electric motor, the “control means” stops the fuel supply to each of the combustion chambers and the electric power input / output by the first and second electric motors The internal combustion engine and the first and second motors are controlled so as to be within the allowable charging power range of the power storage means, and it is determined that there is a possibility that the first motor may over-rotate. If fuel is supplied to at least one of the plurality of combustion chambers when the fuel supply to each of them should be stopped, the amount of fuel necessary to ignite the mixture is supplied. As long as the fuel supply to at least one combustion chamber is stopped as a condition, a combination of the hybrid ECU 70, the engine ECU 24, and the motor ECU 40, such as a single electronic control unit. Be of any other form other than allowed may be. In any case, the correspondence between the main elements of the embodiments and the modified examples and the main elements of the invention described in the column of means for solving the problems is the same as the means for the embodiments to solve the problems. Since this is an example for specifically explaining the best mode for carrying out the invention described in the column, the elements of the invention described in the column for means for solving the problems are not limited. In other words, the examples are merely specific examples of the invention described in the column for means for solving the problem, and the interpretation of the invention described in the column for means for solving the problem is described in the description of the column. Should be done on the basis.

  The embodiments of the present invention have been described above using the embodiments. However, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the present invention. Needless to say.

  The present invention can be used in the manufacturing industry of hybrid vehicles.

It is a schematic block diagram of the hybrid vehicle 20 of an Example. 2 is a schematic configuration diagram of an internal combustion engine device 21. FIG. It is a flowchart which shows an example of the drive control routine performed by hybrid ECU70 of an Example. It is explanatory drawing which shows an example of the map for request | requirement torque setting. It is explanatory drawing which illustrates the correlation curve of the rotation speed Ne and torque Te which shows that the operating line of the engine 22 and request | requirement power Pe * become constant. FIG. 4 is an explanatory diagram illustrating a collinear diagram illustrating a dynamic relationship between the rotational speed and torque of a rotating element in the power distribution and integration mechanism 30 when the hybrid vehicle 20 is running with the engine 22 operated. It is explanatory drawing for demonstrating the setting procedure of torque limitation Tm1min and Tm1max. It is a flowchart which shows an example of the control routine at the time of a fuel cut. It is explanatory drawing which shows an example of the map for minimum injection amount setting. FIG. 9 is a time chart illustrating a state in which fuel injection to each combustion chamber 120 is stopped by executing the fuel cut time control routine of FIG. 8. FIG. It is a schematic block diagram of the hybrid vehicle 20A which concerns on a modification.

Explanation of symbols

  20, 20A hybrid vehicle, 21 internal combustion engine device, 22 engine, 24 engine electronic control unit (engine ECU), 24a, 72 CPU, 24b, 74 ROM, 24c, 76 RAM, 26 crankshaft, 28 damper, 30 power distribution Integrated mechanism, 31 sun gear, 32 ring gear, 32a ring gear shaft, 33 pinion gear, 34 carrier, 35 reduction gear, 37 gear mechanism, 38 differential gear, 39a-39d wheels, 40 electronic control unit for motor (motor ECU), 41, 42 Inverter, 43, 44 Rotation position detection sensor, 50 battery, 51 Temperature sensor, 52 Electronic control unit for battery (battery ECU), 54 Power line, 70 Electronic control unit for hybrid (hybrid E) U), 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal stroke sensor, 87 vehicle speed sensor, 120 combustion chamber, 121 piston, 122 air cleaner, 123 Throttle valve, 124 Throttle valve position sensor, 125 Throttle motor, 126 Intake pipe, 127 Fuel injection valve, 128 Spark plug, 129 Ignition coil, 130 Valve mechanism, 131 Intake valve, 132 Exhaust valve, 133 Cam position sensor, 140 Exhaust manifold, 141 purification device, 142 EGR pipe, 143 EGR valve, 144 Temperature sensor, 180 Crank position sensor, 1 81 Water temperature sensor, 182 In-cylinder pressure sensor, 183 Air flow meter, 184 Intake air temperature sensor, 185 Intake air pressure sensor, 186 Air-fuel ratio sensor, MG1, MG2 motor.

Claims (6)

An internal combustion engine capable of outputting power by burning a mixture of fuel and air in a plurality of combustion chambers;
A first electric motor capable of inputting and outputting power;
A first element connected to the rotating shaft of the first electric motor; a second element connected to the output shaft of the internal combustion engine; and a third element connected to a driving shaft that transmits power to the drive wheels. A planetary gear mechanism configured such that the second element is positioned between the first element and the third element on a collinear diagram, and the three elements can be differentially rotated with respect to each other;
A second electric motor capable of inputting and outputting power to the drive shaft;
Power storage means capable of exchanging power with the first and second motors;
An allowable charge power setting means for setting an allowable charge power allowed for charging the power storage means based on a state of the power storage means;
Based on the number of rotations related to any two of the first to third elements of the planetary gear mechanism, the drive motor suddenly decelerates and the first motor connected to the first element over-rotates. Over-rotation determining means for determining whether there is a risk,
When it is determined by the over-rotation determining means that there is a risk of over-rotation of the first electric motor, fuel supply to each of the combustion chambers is stopped and input / output by the first and second electric motors. The internal combustion engine and the first and second motors are controlled so that the power to be within the range of the allowable charging power set by the allowable charging power setting means, and according to the determination result by the overspeed determination means If the fuel is supplied to at least one of the plurality of combustion chambers when the fuel supply to each of the combustion chambers should be stopped, the amount of fuel required to ignite the mixture is increased. Control means for stopping fuel supply to the at least one combustion chamber on the condition that fuel is supplied;
A hybrid vehicle comprising: The hybrid vehicle according to claim 1,
The hybrid vehicle is configured such that the control means sets an amount necessary for igniting the air-fuel mixture to increase as the intake air amount of the internal combustion engine increases and to decrease as the rotational speed of the internal combustion engine increases. In the hybrid vehicle according to claim 1 or 2,
The over-rotation determination means generates an over-rotation of the first electric motor when the amount of decrease in the rotation speed of the third element is equal to or greater than a predetermined value and the rotation speed of the first element is equal to or greater than a predetermined rotation speed. A hybrid vehicle that determines that there is a risk.   The hybrid vehicle according to any one of claims 1 to 3, wherein the power storage means is a lithium ion secondary battery. In the hybrid vehicle according to any one of claims 1 to 4,
The planetary gear mechanism holds a sun gear connected to a rotation shaft of the first electric motor, a ring gear connected to the drive shaft, and a plurality of pinion gears meshed with both the sun gear and the ring gear, and the internal combustion engine. A hybrid vehicle that is a single pinion planetary gear mechanism including a carrier connected to the output shaft of the vehicle. An internal combustion engine capable of outputting power by burning a mixture of fuel and air in a plurality of combustion chambers, a first motor capable of inputting / outputting power, and a first element connected to a rotating shaft of the first motor And a second element connected to the output shaft of the internal combustion engine, and a third element connected to the drive shaft for transmitting power to the drive wheels, the second element on the nomograph A planetary gear mechanism that is positioned between one element and the third element and configured so that these three elements can rotate differentially with each other; and a second electric motor that can input and output power to the drive shaft; A control method for a hybrid vehicle comprising a power storage means capable of exchanging electric power with the first and second electric motors,
(A) Over-rotation of the first electric motor connected to the first element by rapid deceleration of the drive wheel based on the number of rotations related to any two of the first to third elements of the planetary gear mechanism Determining whether there is a risk of occurrence of
(B) When it is determined by the over-rotation determination means that there is a risk of over-rotation of the first electric motor, fuel supply to each of the combustion chambers is stopped and the first and second electric motors The internal combustion engine and the first and second electric motors are controlled so that the input / output power is within the allowable charging power set by the allowable charging power setting means, and the determination result by the overspeed determination means Required to ignite the air-fuel mixture if the fuel is supplied to at least one of the plurality of combustion chambers when the fuel supply to each of the combustion chambers should be stopped according to Stopping fuel supply to the at least one combustion chamber on the condition that a sufficient amount of fuel has been supplied;
A control method for a hybrid vehicle including:

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