JP5397168B2 - Hybrid vehicle and control method thereof - Google Patents

Description

  The present invention relates to a hybrid vehicle including an internal combustion engine and an electric motor each capable of outputting driving power and a control method thereof.

  Conventionally, a drive motor for driving a vehicle, a chargeable / dischargeable battery as a power source for the drive motor, a generator for charging the battery, an engine having a catalyst device in the exhaust system and driving the generator, A so-called series-type hybrid vehicle is known that includes engine start / stop control means for starting or stopping the engine based on the charge / discharge state of the battery and intake air amount control means for variably controlling the intake air amount of the engine. (For example, refer to Patent Document 1). In this hybrid vehicle, the engine is started when the battery power becomes insufficient, but after the engine is started, the intake air amount suppression period (approximately 20 seconds to 200 seconds) determined based on the coolant temperature at the time of starting the engine. Only by reducing the intake air amount to a small flow rate equivalent to idle, the engine output is suppressed to a small level. Thereby, it is possible to reduce the exhaust exhaust gas flow rate at the stage where the catalyst device after the engine start is not sufficiently warmed up and suppress the deterioration of the emission.

Japanese Patent Laid-Open No. 06-141405

  However, what is described in Patent Document 1 is only a series-type hybrid vehicle. In a hybrid vehicle other than the series-type, for example, the engine is started in response to an increase in driving force demand by the driver after the start of traveling. If the engine output is limited for at least 20 seconds after that, even if it is possible to suppress the deterioration of the emission, it is possible to output the driving torque according to the driving force request operation of the driver. May be difficult.

  Accordingly, the present invention provides a driving force request operation for a driver while suppressing deterioration of emissions immediately after the first start of the internal combustion engine after the start of traveling in a hybrid vehicle including an internal combustion engine and an electric motor each capable of outputting driving power. The main purpose is to obtain a torque for traveling according to the vehicle.

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

The hybrid vehicle according to the present invention
A hybrid vehicle including an internal combustion engine capable of outputting power for traveling, an electric motor capable of outputting power for traveling, and power storage means capable of exchanging electric power with the motor,
Requested torque setting means for setting a requested torque required for traveling in response to a driver's driving force request operation;
Requested engine power setting means for setting requested engine power, which is power required for the internal combustion engine, based on the requested torque set by the requested torque setting means;
Whether the required engine power set by the required engine power setting means after the start of the internal combustion engine in response to the first start request after the start of traveling is equal to or greater than a power limit determination threshold based on the temperature of the internal combustion engine Power limit determination means for determining whether or not
When the power limit determining means determines that the required engine power is less than the power limit determination threshold, the internal combustion engine outputs power based on the required engine power set by the required engine power setting means and The internal combustion engine and the electric motor are controlled so as to obtain a running torque based on the required torque set by the required torque setting means, and the required engine power is greater than or equal to the power limit determination threshold by the power limit determination means. When it is determined that there is, the internal combustion engine is operated independently for a predetermined power limit execution time, and the internal combustion engine and the internal combustion engine are configured to obtain a traveling torque based on the required torque set by the required torque setting means. Control means for controlling the electric motor;
Is provided.

  In this hybrid vehicle, after the start of the internal combustion engine according to the first start request after the start of travel is completed, the required engine power based on the required torque required for travel according to the driving force request operation of the driver is It is determined whether or not the power limit determination threshold is based on the temperature of the current. When it is determined that the required engine power is less than the power limit determination threshold, the internal combustion engine and the electric motor are configured so that the internal combustion engine outputs power based on the required engine power and obtains traveling torque based on the required torque. Is controlled. In other words, if the required engine power is less than the power limit determination threshold value based on the temperature of the internal combustion engine immediately after the first start of the internal combustion engine after the start of traveling, there is little risk of worsening the emission even if the required power is output as it is. Thus, by causing the internal combustion engine to output the required power as it is, it is possible to obtain a traveling torque according to the driving force request operation of the driver. On the other hand, when it is determined that the required engine power is equal to or higher than the power limit determination threshold based on the temperature of the internal combustion engine after the start of the internal combustion engine corresponding to the first start request after the start of traveling is completed, the internal combustion engine is The internal combustion engine and the electric motor are controlled such that the vehicle is operated independently for a predetermined power limit execution time (operated in a substantially no-load state) and travel torque based on the required torque is obtained. That is, after the initial start of the internal combustion engine after the start of running is completed, the deterioration of the emission can be satisfactorily suppressed by operating the internal combustion engine independently for only a few seconds and suppressing the output. Further, if it is a relatively short time after the start of the internal combustion engine, the traveling torque corresponding to the driver's driving force request operation is obtained by the electric power from the power storage means basically without deteriorating the power storage means. Can provide the power for Therefore, when the required engine power becomes equal to or higher than the power limit determination threshold immediately after the internal combustion engine is started for the first time after the start of traveling, the internal combustion engine is independently operated for the power limit execution time and a traveling torque based on the required torque is obtained. In this way, by controlling the internal combustion engine and the electric motor, it is possible to obtain traveling torque in accordance with the driver's driving force request operation while suppressing deterioration of emissions immediately after the internal combustion engine is started for the first time after the start of traveling. It becomes.

  In the hybrid vehicle, the power storage means may be capable of being charged with electric power from an external power source. That is, in a so-called plug-in hybrid vehicle in which the power storage means can be charged in advance by the electric power from the external power supply before the start of traveling, the operation of the internal combustion engine is stopped for a while after the start of traveling. It is assumed that the internal combustion engine is often started only when a relatively large power is required for the vehicle by the driver's driving force request operation. In addition, it is assumed that the charging rate of the power storage means is secured to some extent at the time when the internal combustion engine is started in response to a relatively large power demand. In such a case, the operation is performed using the power from the power storage means. It is possible to satisfactorily provide power for obtaining torque for traveling according to the user's driving force request operation. Therefore, according to the present invention, in a plug-in hybrid vehicle, a traveling torque corresponding to a driver's driving force request operation can be obtained while suppressing deterioration of emissions immediately after the internal combustion engine is started for the first time after the start of traveling. Is possible.

  Further, the hybrid vehicle sets an output limit that is electric power allowed for discharging the power storage means based on a state of the power storage means, and the requested engine power is set to the power limit determination threshold by the power limit determination means. An output limit setting unit that temporarily increases the output limit when it is determined to be above may be provided, and the control unit includes the request within a range of the output limit set by the output limit setting unit. The internal combustion engine and the electric motor may be controlled so that a running torque based on the required torque set by the torque setting means is obtained. Thus, if the output limit of the power storage means is temporarily increased immediately after the initial start of the internal combustion engine after the start of traveling, it becomes possible to output a larger traveling torque from the electric motor at that time, Even if the internal combustion engine is autonomously operated so that it does not substantially output torque immediately after the first start after the start of traveling, it is possible to obtain traveling torque in accordance with the driving force requesting operation of the driver.

  The power limit determination threshold value may be set so as to increase as the temperature of the internal combustion engine increases. As a result, it is possible to make the power limit determination threshold more appropriate in achieving both suppression of deterioration of emission and securing of torque for traveling.

  Further, the power limit execution time tends to be shorter as the first time set to be shorter as the temperature of the internal combustion engine is higher and the required engine power set by the required engine power setting means is larger. It may be the shorter one of the set second times. As a result, it is possible to make the power limit execution time more appropriate in achieving both suppression of deterioration of emission and securing of torque for traveling.

  The hybrid vehicle can input and output power and can exchange electric power with the power storage means; a first element connected to an output shaft of the internal combustion engine; and the second element A planetary gear mechanism having a second element connected to the rotating shaft of the electric motor and a third element connected to the driving shaft connected to the driving wheel and configured so that these three elements can be differentially rotated with respect to each other; The motor may be capable of outputting power to the drive shaft, and the control means can obtain a running torque based on the required torque set by the required torque setting means. As described above, the internal combustion engine, the electric motor, and the second electric motor may be controlled.

The hybrid vehicle control method according to the present invention includes:
A control method for a hybrid vehicle comprising an internal combustion engine capable of outputting power for traveling, an electric motor capable of outputting power for traveling, and power storage means capable of exchanging electric power with the motor,
(A) a step of setting a required torque required for traveling according to a driver's driving force request operation;
(B) setting required engine power, which is power required for the internal combustion engine, based on the required torque set in step (a);
(C) The required engine power set in step (b) after the start of the internal combustion engine in response to the first start request after the start of traveling is equal to or greater than a power limit determination threshold based on the temperature of the internal combustion engine. Determining whether or not,
(D) When it is determined in step (c) that the required engine power is less than the power limit determination threshold, the internal combustion engine outputs power based on the required engine power set in step (b). In addition, the internal combustion engine and the electric motor are controlled so that a running torque based on the required torque set in step (a) is obtained, and in step (c), the required engine power becomes the power limit determination threshold value. When it is determined that the above is satisfied, the internal combustion engine is operated independently for a predetermined power limit execution time and the traveling torque based on the required torque set in step (a) is obtained. And controlling the electric motor;
Is included.

  According to this method, in a hybrid vehicle including an internal combustion engine and an electric motor each capable of outputting power for traveling, a driver's driving force request operation is performed while suppressing deterioration of emissions immediately after the initial start of the internal combustion engine after the start of traveling. It is possible to obtain a running torque according to the above.

1 is a schematic configuration diagram of a hybrid vehicle 20 that is a hybrid vehicle according to an embodiment of the present invention. 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 shows an example of the map for power restriction determination threshold value setting. It is explanatory drawing which shows an example of the map for water temperature origin restriction | limiting execution time setting. It is explanatory drawing which shows an example of the map for power origin restriction | limiting execution time setting. 3 is an explanatory diagram showing an example of a collinear diagram showing a dynamic relationship between the number of rotations and torque in a rotating element of the power distribution and integration mechanism 30. FIG. It is explanatory drawing which illustrates the correlation curve of the operating line of the engine 22, rotation speed Ne, and torque Te. It is a schematic block diagram of the hybrid vehicle 120 which concerns on a modification.

  Next, the form for implementing this invention is demonstrated using an Example.

  FIG. 1 is a schematic configuration diagram of a hybrid vehicle 20 that is a hybrid vehicle according to an embodiment of the present invention. A hybrid vehicle 20 shown in the figure is connected to 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, and the power distribution and integration mechanism 30. The motor MG1 capable of generating electricity, the reduction gear 35 coupled to the ring gear shaft 32a as the drive shaft connected to the power distribution and integration mechanism 30, and the motor MG2 connected to the ring gear shaft 32a via the reduction gear 35 And a battery 50 capable of exchanging electric power with the motors MG1 and MG2, 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 is an internal combustion engine that outputs power when supplied with hydrocarbon-based fuel such as gasoline or light oil. The fuel injection amount or ignition timing by an engine electronic control unit (hereinafter referred to as “engine ECU”) 24, Receive control of intake air volume. The engine ECU 24 receives signals from various sensors that are provided for the engine 22 such as a water temperature sensor (not shown) that detects the temperature of cooling water of the engine 22 and that detects the operating state of the engine 22. The engine ECU 24 communicates with the hybrid ECU 70 to control the operation of the engine 22 based on a control signal from the hybrid ECU 70, a signal from the sensor, and the like, and to transmit data on the operation state of the engine 22 as necessary. It outputs to ECU70.

  The power distribution and integration mechanism 30 includes an external gear sun gear 31, an internal gear ring gear 32 arranged 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, This is a single pinion type planetary gear mechanism that has a carrier 34 that holds a plurality of pinion gears 33 so as to rotate and revolve, and that these three elements can be differentially rotated with respect to each other. The carrier 34 which is the first element of the power distribution and integration mechanism 30 has the crankshaft 26 of the engine 22, the sun gear 31 which is the second element, the rotation shaft of the motor MG1, and the ring gear 32 which is the third element. The rotation shafts of the motor MG2 are connected to each other through the shaft 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 through the gear train 37 and the differential gear 38 to the wheels 39a and 39b that are drive wheels.

  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 a motor, and exchanges power with the 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 supplied to the other. It can be consumed with the motor. Therefore, the battery 50 is charged / discharged by the electric power generated from one of the motors MG1 and MG2 or the insufficient electric power, and the battery 50 is not charged / discharged if the electric power balance is balanced by the motors MG1 and MG2. Become. 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 is 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, and controls the drive of the motors MG1 and MG2 based on a control signal from the hybrid ECU 70 and transmits data related to the operation state of the motors MG1 and 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 Tbat 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 (charging ratio) SOC based on the integrated value of the charging / discharging current detected by the current sensor, or based on the remaining capacity SOC. The charge / discharge required power Pb * is calculated, the input limit Win, which is the power allowed for charging the battery 50 based on the remaining capacity SOC and the battery temperature Tbat, and the output, which is the power allowed for discharging the battery 50 The limit Wout is calculated. In the embodiment, 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 Tbat, and the output limiting correction coefficient based on the remaining capacity SOC of the battery 50. It is 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.

  In addition, the hybrid vehicle 20 of the embodiment is configured as a so-called plug-in hybrid vehicle, and includes a vehicle-side connector 62 connected to an external power supply-side connector 92 of an external power supply 90 such as a household power supply (AC100V), a vehicle Charging relay 64 capable of executing connection / disconnection of the side connector 62 and the power line 54, an AC / DC converter 66 for converting AC power from the external power supply 90 into DC power, and an AC / DC converter 66 DC / DC converter 68 that converts the DC power voltage from the battery 50 and supplies it to the battery 50 side, and a charging electronic control unit (hereinafter referred to as the charging relay 64, AC / DC converter 66, DC / DC converter 68). 60 (referred to as “charging ECU”). The charging ECU 60 communicates with the hybrid ECU 70 and the battery ECU 52, and exchanges various data with the hybrid ECU 70 and the like as necessary. Thereby, in the hybrid vehicle 20 of an Example, the battery 50 can be charged with the electric power from the external power supply 90 before a driving | running | working start. In the embodiment, a charging upper limit in which a value (for example, a value of about 78 to 79%) slightly smaller than the normal upper limit Snlim (80%) of the remaining capacity SOC is an upper limit remaining capacity (target remaining capacity) when charging by the external power source 90. When charging the battery 50 with the electric power from the external power supply 90, the charging ECU 60 sets the charging relay 64 and the AC / DC converter 66 so that the remaining capacity SOC of the battery 50 becomes the charging upper limit Scrim. The DC / DC converter 68 is controlled. Note that the above-described charging upper limit Sclim may be the same value as the common upper limit Snlim.

  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 includes an ignition signal from an ignition switch (start switch) 80, a shift position SP from a shift position sensor 82 that detects a shift position SP that is an operation position of the shift lever 81, and a depression amount of an accelerator pedal 83 (accelerator operation). The accelerator pedal position Acc from the accelerator pedal position sensor 84 for detecting the amount), 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, etc. Is input via. As described above, the hybrid ECU 70 is connected to the engine ECU 24, the motor ECU 40, the battery ECU 52, the charging ECU 60, and the like via a communication port. The hybrid ECU 70 is variously connected to the engine ECU 24, the motor ECU 40, the battery ECU 52, the charging ECU 60, and the like. Exchange control signals and data.

  In the hybrid vehicle 20 of the embodiment configured as described above, the vehicle is connected to the wheels 39a and 39b which are driving 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 as the drive shaft is calculated, and the engine 22, the motor MG1, and the motor MG2 are controlled so that the torque based on the required torque Tr * is output to the ring gear shaft 32a. . As an operation control mode of the engine 22, the motor MG1, and the motor MG2, the operation of the engine 22 is controlled so that power corresponding to the required torque Tr * is output from the engine 22, and all of the power output from the engine 22 is distributed. Necessary for torque conversion operation mode in which motor MG1 and motor MG2 are driven and controlled so that torque is converted by integrated mechanism 30, motor MG1 and motor MG2 and output to ring gear shaft 32a, and required torque Tr * and charge / discharge of battery 50 The engine 22 is operated and controlled so that a power corresponding to the sum of the power and the power is output from the engine 22, and all or a part of the power output from the engine 22 with charging / discharging of the battery 50 is a power distribution and integration mechanism. 30 and torque conversion by motor MG1 and motor MG2. Thus, a charge / discharge operation mode in which the motor MG1 and the motor MG2 are driven and controlled so that torque based on the required torque Tr * is output to the ring gear shaft 32a, and the operation based on the required torque Tr * is stopped by stopping the operation of the engine 22. There is a motor operation mode in which the motor MG2 is driven and controlled to output to 32a.

  In addition, since the hybrid vehicle 20 of the embodiment is configured as a plug-in hybrid vehicle as described above, the battery 50 may be charged in advance by the electric power from the external power supply 90 before the start of traveling. it can. Therefore, when traveling is started after charging using the external power source 90, the hybrid vehicle 20 basically travels with power from only the motor MG2 under the motor operation mode until a predetermined engine start condition is satisfied. To do. When the engine start condition is satisfied during traveling under the motor operation mode, the motor MG1 is driven and controlled so as to crank the engine 22, and the driving torque acting on the ring gear shaft 32a according to the cranking is controlled. The engine 22 is started by controlling the motor MG2 so that torque based on the required torque Tr * is output to the ring gear shaft 32a while canceling the torque as the reaction force. The engine start condition in the embodiment is that the remaining capacity SOC of the battery 50 is less than a predetermined lower limit remaining capacity Sref (for example, a value of about 20 to 40%), and the vehicle speed V is a predetermined value (for example, 100 km). / H) or the input limit Win of the battery 50 is smaller than the charging power (the larger the value) is, the lower the intermittent prohibition vehicle speed Vref is set, or the required torque Tr * to be output to the ring gear shaft 32a is set to the required torque Tr *. The required travel power Pr * required for travel of the hybrid vehicle 20 obtained by multiplying the rotational speed Nr of the engine and the power consumed by cranking by the motor MG1 for starting the engine 22 (negative value, that is, generated power) Power for starting the engine and air conditioning in the passenger compartment by an air conditioning unit (not shown) The air-conditioning power demanded (the power for driving the compressor, etc.), total required power Ptotal, which is the sum of the predetermined margin of power and the like that is the output limit Wout or more batteries 50.

  Next, the operation of the hybrid vehicle 20 according to the embodiment, particularly the operation immediately after the engine 22 is started in accordance with the establishment of the engine start condition during traveling under the motor operation mode of the hybrid vehicle 20 will be described. FIG. 2 is a flowchart illustrating an example of a drive control routine executed by the hybrid ECU 70 of the embodiment. This routine is repeatedly executed every predetermined time (for example, every several msec) when the accelerator pedal 83 is depressed by the driver after the engine 22 is started in accordance with the establishment of the engine start condition.

  At the start of the routine of FIG. 3, the CPU 72 of the hybrid ECU 70 charges the accelerator opening Acc from the accelerator pedal position sensor 84, the vehicle speed V from the vehicle speed sensor 87, the rotational speeds Nm1, Nm2 of the motors MG1, MG2, and the charging of the battery 50. Input processing of data required for control such as required discharge power Pb *, input / output limits Win and Wout, the coolant temperature Tw of the engine 22, the value of the initial start flag Ffs, and the elapsed time tas after engine start is executed (step S100). . Here, the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 are calculated by the motor ECU 40 based on signals from the rotational position detection sensors 43 and 44, and are input by communication from the motor ECU 40 to charge the battery 50. The required discharge power Pb * and the input / output limits Win and Wout are input from the battery ECU 52 by communication. The coolant temperature Tw of the engine 22 is detected by a water temperature sensor (not shown) of the engine 22 and is input from the engine ECU 24 by communication. Further, in the embodiment, the initial start flag Ffs is set when the engine 22 is started in response to the first engine start request after the hybrid vehicle 20 starts running, that is, the engine start condition is satisfied and the engine 22 is started. When set, the value is set to 1 by the engine ECU 24 and is input from the engine ECU 24 by communication. The elapsed time tas after engine start is measured by a timer (not shown) of the engine ECU 24 when the engine start condition is satisfied and the engine 22 is started, and is input from the engine ECU 24 by communication.

  After the data input process in step S100, the required power Perq required for the engine 22 is set after setting the required torque Tr * to be output to the ring gear shaft 32a based on the input accelerator opening Acc and the vehicle speed V. (Step S110). 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. 3 shows an example of the required torque setting map. Further, in the embodiment, the required power Perq is calculated as the 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. That is, the required power Perq is the sum of the power required to output the required torque Tr * to the ring gear shaft 32a as the drive shaft, the power required to charge / discharge the battery 50, and the 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, it is determined whether or not the initial start flag Ffs input in step S100 is a value 1 (step S120). If the initial start flag Ffs is a value 1, whether or not the output of the engine 22 should be limited. A power limit determination threshold value Pref for determining whether or not is set based on the coolant temperature Tw input in step S100 (step S130). In the embodiment, the relationship between the coolant temperature Tw indicating the temperature of the engine 22 and the power limit determination threshold value Pref that is the engine power when the emission of the engine 22 is outside the allowable range is determined in advance, and the power limit determination threshold value setting is performed. As a power map, it is stored in the ROM 74, and a power limit determination threshold value Pref corresponding to the given cooling water temperature Tw is derived and set from the map. FIG. 4 shows an example of the power limit determination threshold setting map. As shown in the figure, the power limit determination threshold value setting map is basically created so that the power limit determination threshold value Pref tends to be regulated to be larger as the coolant temperature Tw is higher. That is, the power limit determination threshold value setting map of the embodiment has a power limit determination threshold value Pref of 0 when the cooling water temperature Tw is equal to or lower than a temperature Ta (for example, 20 ° C.), and the cooling water temperature Tw is changed from the temperature Ta to the temperature Ta. When the cooling water temperature Tw is higher when the temperature is in the range up to Tb (for example, 80 ° C.), the power limit determination threshold value Pref is specified to be larger. When the cooling water temperature Tw is equal to or higher than the temperature Tb, the power limit determination threshold value Pref is infinite. Created to be big.

  If the power limit determination threshold value Pref is set, it is determined whether or not the required power Perq set in step S110 is equal to or greater than the power limit determination threshold value Pref (step S140), and the required power Perq is equal to or greater than the power limit determination threshold value Pref. If so, the water temperature-based limit execution time (first time) tw is set based on the coolant temperature Tw of the engine 22, and the power-based limit execution time (first time) based on the required power Perq set in step S110. (Time 2) tp is set (step S150). In the embodiment, the relationship between the cooling water temperature Tw and the water temperature-based limit execution time tw is determined in advance and stored in the ROM 74 as a water temperature-based limit execution time setting map, and is given as the water temperature-based limit execution time tw. Those corresponding to the cooling water temperature Tw are derived and set from the map. FIG. 5 shows an example of a map for setting the water temperature-induced limit execution time. As shown in the figure, the water temperature-based limited execution time setting map is basically created so that the higher the cooling water temperature Tw indicating the temperature of the engine 22, the shorter the water temperature-based limited execution time tw tends to be specified. Is done. That is, the water temperature-based limited execution time setting map of the embodiment sets the water temperature-based limited execution time tw to a value t1 (for example, 10 seconds) when the cooling water temperature Tw is 0 ° C. or less, and the cooling water temperature Tw is 0. When the cooling water temperature Tw is higher when the temperature is in the range from ° C. to Tb (for example, 80 ° C.), the water temperature-based restriction execution time tw is set shorter, and when the cooling water temperature Tw is equal to or higher than the temperature Tb, the water temperature-related restriction It is created so that the execution time tw is 0.

  In the embodiment, the relationship between the required power Perq and the power-based limited execution time tp is predetermined and stored in the ROM 74 as a power-based limited execution time setting map, and the power-based limited execution time tp is given as The one corresponding to the requested power Perq is derived and set from the map. FIG. 6 shows an example of a map for setting the power-induced limit execution time. As shown in the figure, the power-based limited execution time setting map is basically created so that the power-based limited execution time tp tends to be defined shorter as the required power Perq for the engine 22 is larger. That is, the power-based limited execution time setting map of the embodiment sets the power-based limited execution time tw to a value t2 (for example, 10 seconds) when the required power Perq is 0, and the required power Perq is a predetermined value from the value 0. When the required power Perq is larger when it is within a range up to Px (for example, 40 kW), the power-based limited execution time tp is specified to be shorter. When the required power Perq is equal to or greater than the predetermined value Px, the power-based limited execution time tp is set to a value. It is created to be 0.

  When the water temperature-based limited execution time tw and the power-based limited execution time tp are thus set, the smaller one of the water temperature-based limited execution time tw and the power-based limited execution time tp is set as the limited execution time tref. (Step S160), it is determined whether or not the elapsed time tas after engine start input in Step S100 is equal to or shorter than the limit execution time tref (Step S170). If the elapsed time tas after engine start is equal to or less than the limit execution time tref, the target power Pe *, which is the target value of the power to be output from the engine 22, is set to a value of 0, and the target rotational speed Ne * of the engine 22 is determined in advance. The obtained independent rotation speed Nref is set (step S180). The self-supporting rotational speed Nref is a rotational speed when the engine 22 is operated so as not to substantially output torque, and is set to a rotational speed at idle or a value close thereto (for example, 800 to 1200 rpm) in the embodiment. After the process of step S180, the set target power Pe * and the target rotational speed Ne * and the autonomous operation command for allowing the engine 22 to autonomously operate are transmitted to the engine ECU 24 (step S190). It is determined whether the elapsed time tas after engine start input in S100 is equal to or shorter than a predetermined time tout (for example, about 3 seconds) (step S200). The predetermined time tout used in step S200 is a time allowed to temporarily increase the output limit Wout of the battery 50, and is determined in advance through experiments and analysis. If the elapsed time tas after the engine start is equal to or less than the predetermined time tout, a value obtained by adding the predetermined value ΔW to the output limit Wout input in step S100 and a predetermined upper limit value Wmax of the output limit Wout Is reset as the output limit Wout of the battery 50 (step S210). If it is determined in step S200 that the elapsed time tas after engine startup has exceeded the predetermined time tout, the process of step S210 is skipped.

  Next, using the target rotational speed Ne *, the rotational speed Nr (Nm2 / Gr) of the ring gear shaft 32a, and the gear ratio ρ of the power distribution and integration mechanism 30 (the number of teeth of the sun gear 31 / the number of teeth of the ring gear 32), 1) After calculating the target rotational speed Nm1 * of the motor MG1, a torque command for the motor MG1 according to the following equation (2) using the target torque Te *, the calculated target rotational speed Nm1 *, the current rotational speed Nm1, etc. Tm1 * is set (step S220). Here, Expression (1) is a dynamic relational expression for the rotating element of the power distribution and integration mechanism 30. FIG. 7 illustrates a collinear diagram illustrating a dynamic relationship between the rotational speed and torque in the rotating element 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)
Tm1 * =-ρ / (1 + ρ) ・ Te * + k1 ・ (Nm1 * -Nm1) + k2 ・ ∫ (Nm1 * -Nm1) dt (2)

  If torque command Tm1 * for motor MG1 is set, input / output limits Win and Wout of battery 50, torque command Tm1 * for motor MG1 set in step S220, and current rotational speeds Nm1 and Nm2 of motors MG1 and MG2 Is used to calculate torque limits Tmin and Tmax as upper and lower limits of the torque that may be output from the motor MG2 according to the following equations (3) and (4) (step S230). Further, a temporary motor torque Tm2tmp which is a temporary value of torque to 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. Is calculated according to the following equation (5) (step S240). 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 Tmin and Tmax (step S250). Thus, by setting the torque command Tm2 * for the motor MG2, the torque output to the ring gear shaft 32a can be 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. If torque commands Tm1 * and Tm2 * for motors MG1 and MG2 are set in this way, torque commands Tm1 * and Tm2 * for motors MG1 and MG2 are transmitted to motor ECU 40 (step S260), and the processing after step S100 is performed again. Run.

Tmin = (Win-Tm1 * ・ Nm1) / Nm2 (3)
Tmax = (Wout-Tm1 * ・ Nm1) / Nm2 (4)
Tm2tmp = (Tr * + Tm1 * / ρ) / Gr (5)

  Receiving the torque commands Tm1 * and Tm2 *, the motor ECU 40 controls 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 *. Do. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * also controls throttle opening control, fuel injection control, and ignition timing so that the engine 22 operates according to the target rotational speed Ne * and the target torque Te *. Execute control etc.

  On the other hand, if it is determined in step S120 that the initial start flag Ffs is 0, the initial start flag Ffs is set (maintained) to 0 and the elapsed time tas after engine start is reset (step S120). S270), the required power Perq set in step S110 is set to the target power Pe * of the engine 22, and the target rotational speed Ne * of the engine 22 is set based on the set target power Pe *, and the target power Pe * The target rotational speed Ne * is transmitted to the engine ECU 24 (step S280). In the embodiment, the target rotational speed Ne * of the engine 22 is set based on a predetermined operation line and the target power Pe * in order to operate the engine 22 efficiently. FIG. 8 illustrates a correlation curve between the rotational speed Ne and the torque Te indicating that the operation line of the engine 22 and the target engine power Pe * are constant. As shown in the figure, the target rotational speed Ne * can be obtained from the intersection of the operation line and a correlation curve indicating that the target engine power Pe * (Ne × Te) is constant. Even if it is determined in step S120 that the initial start flag Ffs is a value 1, if it is determined in step S140 that the required power Perq is less than the power limit determination threshold Pref, the initial start flag Ffs is set to the value. After setting (maintaining) 0 and resetting the elapsed time tas after engine start (step S270), the required power Perq set in step S110 is set to the target power Pe * of the engine 22 and the set target power Pe Based on *, the target rotational speed Ne * of the engine 22 is set, and the target power Pe * and the target rotational speed Ne * are transmitted to the engine ECU 24 (step S280). Further, after the processing from step S180 to S210 is once executed, if it is determined in step S200 that the elapsed time tas after engine start has exceeded the limit execution time tref, the initial start flag Ffs is set. After setting (maintaining) 0 and resetting the elapsed time tas after engine start (step S270), the required power Perq set in step S110 is set to the target power Pe * of the engine 22 and the set target power Pe Based on *, the target rotational speed Ne * of the engine 22 is set, and the target power Pe * and the target rotational speed Ne * are transmitted to the engine ECU 24 (step S280). Then, after the process of step S280, the processes of steps S220 to S260 described above are executed.

  As a result, in the hybrid vehicle 20 of the embodiment, the required power Perq based on the required torque Tr * corresponding to the driver's accelerator operation is obtained immediately after the engine start condition is satisfied first after the start of running and the engine 22 is started. If it is determined that the power limit determination threshold value Pref based on the cooling water temperature Tw indicating the temperature of 22 is equal to or greater than the engine start elapsed time tas, the water temperature-based limit execution time tw based on the cooling water temperature Tw and the request Until the limit execution time tref, which is the smaller of the power-based limit execution time tp based on the power Perq, is exceeded, the engine 22 is autonomously operated so as not to substantially output torque and travel based on the required torque Tr *. The engine 22 and the motors MG1 and MG2 are controlled so that the required torque is obtained. Further, immediately after the engine start condition is satisfied and the engine 22 is started after the start of traveling, the required power Perq based on the required torque Tr * corresponding to the driver's accelerator operation indicates the coolant temperature Tw indicating the temperature of the engine 22. When it is determined that the engine 22 is less than the power limit determination threshold value Pref, or after it is determined that the elapsed time tas after engine startup has exceeded the limit execution time tref, the target power Pe * that matches the required power Perq. And the engine 22 and the motors MG1 and MG2 are controlled so that a traveling torque based on the required torque Tr * is obtained.

  As described above, in the hybrid vehicle 20 of the embodiment, after the start of the engine 22 corresponding to the first start request after the start of traveling is completed, the required torque corresponding to the driver's accelerator operation (driving force request operation). It is determined whether or not the required power Perq based on Tr * is greater than or equal to the power limit determination threshold value Pref based on the coolant temperature Tw indicating the temperature of the engine 22 (step S140). When it is determined that the required power Perq is less than the power limit determination threshold value Pref, the engine 22 outputs the target power Pe * that matches the required power Perq and obtains a running torque based on the required torque Tr *. Thus, engine 22 and motors MG1 and MG2 are controlled (steps S280, S220 to S260). That is, if the required power Perq is less than the power limit determination threshold value Pref immediately after the engine 22 is started for the first time after the start of traveling, there is little risk of worsening the emission even if the engine 22 outputs the required power Perq as it is. By outputting the required power Perq as it is, it is possible to obtain a running torque corresponding to the driver's accelerator operation.

  On the other hand, it is determined that the required power Perq is equal to or higher than the power limit determination threshold value Pref based on the coolant temperature Tw indicating the temperature of the engine 22 after the start of the engine 22 corresponding to the first start request after the start of traveling is completed. When the engine 22 is operated, the engine 22 and the motor MG1 are operated such that the engine 22 is independently operated for the power limit execution time tref (operated substantially in a no-load state) and a traveling torque based on the required torque Tr * is obtained. And MG2 are controlled (steps S180 to S260). That is, if the engine 22 is operated independently for at least 0.5 to 1 second, more preferably about several seconds after the initial start of the engine 22 after the start of traveling, and the output is suppressed, the intake air amount of the engine 22 is constant. In addition, since the amount is small, combustion is stabilized and the amount of exhaust gas (HC) is reduced, so that even if the exhaust purification catalyst (not shown) is not completely warmed up, the deterioration of emissions can be satisfactorily suppressed. it can. In addition, if it is a short time (about 0.5 to 1 second or several seconds) after the start of the engine 22, the battery 50 basically responds to the driver's accelerator operation with the electric power from the battery 50 without deteriorating the battery 50. The power to obtain the driving torque can be provided. Accordingly, when the required power Perq is equal to or greater than the power limit determination threshold value Pref immediately after the engine 22 is started for the first time after the start of driving, the engine 22 is operated independently for the power limit execution time tref and is used for driving based on the required torque Tr *. By controlling the engine 22 and the motors MG1 and MG2 so that torque can be obtained, the torque for traveling according to the accelerator operation of the driver while suppressing the deterioration of emissions immediately after the engine 22 is started for the first time after the start of traveling. Can be obtained.

  Further, the hybrid vehicle 20 of the embodiment is configured as a so-called plug-in hybrid vehicle in which the battery 50 can be charged in advance by the electric power from the external power supply 90 before the start of traveling. 20, the engine 22 is kept running for a while after the start of running, and the engine 22 is only in a stage where a relatively large power is required for the vehicle by the driver's accelerator operation. It is assumed that will be started more often. It is assumed that the remaining capacity SOC of the battery 50 is often secured to some extent at the time when the engine 22 is started in response to a relatively large power request. In such a case, the power from the battery 50 is Thus, it is possible to satisfactorily cover the power for obtaining the driving torque according to the driver's accelerator operation. Therefore, in the hybrid vehicle 20 of the embodiment, it is possible to satisfactorily obtain the torque for traveling according to the driver's accelerator operation while suppressing the deterioration of the emission immediately after the engine 22 is started for the first time after the start of traveling. In the hybrid vehicle 20 of the embodiment, the engine 22 is started when the total required power Ptotal based on the required travel power Pr * and the like required for travel exceeds the output limit Wout of the battery 50. In order to secure a larger remaining capacity SOC (output limit Wout) of the battery 50 at the time when the engine 22 is started in response to a request for large power, until the engine 22 is started for the first time after the start of traveling, For example, by setting a value obtained by subtracting a predetermined value from the output limit Wout of the battery 50 as a threshold value to be compared with the total required power Ptotal, the threshold value may be made smaller than those used thereafter.

  Further, in hybrid vehicle 20 of the embodiment, output limit Wout is set by battery ECU 52 based on battery temperature Tbat and remaining capacity SOC, and required power Perq immediately after the initial start of engine 22 after the start of traveling in step S140. Is determined to be equal to or greater than the power limit determination threshold value Pref, the output limit Wout based on the state of the battery 50 (battery temperature Tbat and remaining capacity SOC) is temporarily increased (reset) (step S210). Thus, if the output limit Wout of the battery 50 is temporarily increased immediately after the engine 22 is started for the first time after the start of traveling, a larger traveling torque can be output from the motor MG2 at that time. Therefore, even if the engine 22 is autonomously operated so that the engine 22 does not substantially output torque immediately after the initial start of the engine 22 after the start of traveling, it is possible to obtain better traveling torque according to the driver's accelerator operation. Can do.

  Moreover, if the power limit determination threshold value Pref is set to increase as the temperature of the engine 22, that is, the coolant temperature Tw increases, as in the above-described embodiment, the power limit determination threshold value Pref can be used for suppressing emission deterioration and for traveling. It is possible to make it more appropriate in achieving both securing of torque. Further, as in the above embodiment, the power limit execution time tref is set such that the power limit execution time tref is set to be shorter as the temperature of the engine 22, that is, the coolant temperature Tw is higher, and step S110. If the shorter one of the power-based limited execution time (second time) tp, which tends to be shorter as the required power Perq set in (2) is larger, the power limited execution time tref is set to reduce the emission. It becomes possible to make it more appropriate in achieving both suppression and securing of traveling torque. However, the power limit execution time tref is a water temperature-based limit execution time tw, a power-based limit execution time tp, and a predetermined time (third time) tout allowed to temporarily increase the output limit Wout of the battery 50. May be the shortest of these times.

  In the hybrid vehicle 20, the ring gear shaft 32 a and the motor MG 2 are connected via a reduction gear 35 that reduces the rotational speed of the motor MG 2 and transmits it to the ring gear shaft 32 a, but instead of the reduction gear 35, For example, a transmission that has two shift stages of Hi and Lo, or three or more shift stages, and changes the rotational speed of the motor MG2 and transmits it to the ring gear shaft 32a may be employed. Furthermore, although the hybrid vehicle 20 decelerates the power of the motor MG2 by the reduction gear 35 and outputs it to the ring gear shaft 32a, the application target of the present invention is not limited to this. That is, according to the present invention, as in a hybrid vehicle 120 as a modified example shown in FIG. 9, the power of the motor MG2 is connected to the ring gear shaft 32a (the axle to which the wheels 39a and 39b as drive wheels are connected). May be applied to those that output to different axles (axles connected to the wheels 39c, 39d in FIG. 9).

  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 embodiment, the engine 22 that can output power to the ring gear shaft 32a corresponds to an “internal combustion engine”, the motor MG2 that can output power to the ring gear shaft 32a corresponds to an “electric motor”, and the motor MG2 and the like. The battery 50 that can exchange electric power with the battery 50 and can be charged by the electric power from the external power source 90 corresponds to the “power storage means”, and the hybrid ECU 70 that executes the process of step S110 in FIG. The hybrid ECU 70 that corresponds to the “required engine power setting means” and that executes the processes of steps S120 to S140 in FIG. 2 corresponds to the “power limit determination means” and that executes the processes of steps S180 to S280 in FIG. The combination of the ECU 70, the engine ECU 24 and the motor ECU 40 is “control”. It corresponds to the stage. " Further, the combination of the battery ECU 52 and the hybrid ECU 70 that executes the processes of steps S200 and S210 in FIG. 2 corresponds to “output limit setting means”, the motor MG1 corresponds to “second electric motor”, and the power distribution integration mechanism 30 corresponds to a “planetary gear mechanism”.

  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 “motor” and “second motor” are not limited to the synchronous generator motors such as the motors MG1 and MG2, and may be of any other type such as an induction motor. The “storage means” may be of any type as long as it can exchange electric power with an electric motor or a generator motor. If the “request torque setting means” is to set the required torque required for traveling according to the driving force request operation of the driver, for example, the required torque is set based only on the accelerator opening Acc. Any other format may be used. The “required engine power setting means” may be of any type as long as it sets the required engine power, which is the power required for the internal combustion engine, based on the required torque. The “control means” may be of any type other than the combination of the hybrid ECU 70, the engine ECU 24, and the motor ECU 40 such as a single electronic control unit. In any case, the correspondence between the main elements of the embodiments and the main elements of the invention described in the column of means for solving the problem is described in the column of means for the embodiment to solve the problem. Therefore, the present invention is not limited to the elements of the invention described in the column of means for solving the problem. In other words, the examples are merely specific examples of the invention described in the column of means for solving the problem, and the interpretation of the invention described in the column of means for solving the problem is described in the description of that 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.

  20, 120 Hybrid vehicle, 22 engine, 24 electronic control unit (engine ECU) for engine, 26 crankshaft, 28 damper, 30 power distribution integration mechanism, 31 sun gear, 32 ring gear, 32a ring gear shaft, 33 pinion gear, 34 carrier, 35 Reduction gear, 37 gear train, 38 differential gear, 39a, 39b, 39c, 39d wheels, 40 electronic control unit for motor (motor ECU), 41, 42 inverter, 43, 44 rotational position detection sensor, 50 battery, 51 temperature sensor , 52 Battery electronic control unit (battery ECU), 54 Electric power line, 60 Charging electronic control unit (charging ECU), 62 Vehicle side connector, 64 Charging relay, 66 AC / DC converter, 68 D / DC converter, 70 Hybrid electronic control unit (hybrid ECU), 72 CPU, 74 ROM, 76 RAM, 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, 90 External power supply, 92 External power supply side connector, MG1, MG2 motor.

Claims (7)

A hybrid vehicle comprising: an internal combustion engine capable of outputting traveling power to a drive shaft; an electric motor capable of outputting traveling power to the drive shaft; and a storage means capable of exchanging electric power with the motor,
Requested torque setting means for setting a requested torque required for traveling in response to a driver's driving force request operation;
Requested engine power setting means for setting requested engine power, which is power required for the internal combustion engine, based on the requested torque set by the requested torque setting means;
Whether the required engine power set by the required engine power setting means after the start of the internal combustion engine in response to the first start request after the start of traveling is equal to or greater than a power limit determination threshold based on the temperature of the internal combustion engine Power limit determination means for determining whether or not
When the power limit determining means determines that the required engine power is less than the power limit determination threshold, the internal combustion engine outputs power based on the required engine power set by the required engine power setting means and The internal combustion engine and the electric motor are controlled so that a traveling torque based on the required torque set by the required torque setting means is output to the drive shaft, and the required engine power is converted to the power by the power limit determining means. When it is determined that it is greater than or equal to a limit determination threshold, the internal combustion engine is operated independently for a predetermined power limit execution time, and traveling torque based on the required torque set by the required torque setting means is applied to the drive shaft. Control means for controlling the internal combustion engine and the electric motor to be output ;
A hybrid vehicle comprising: The hybrid vehicle according to claim 1,
The power storage means is a hybrid vehicle that can be charged with electric power from an external power source. In the hybrid vehicle according to claim 1 or 2,
Based on the state of the power storage means, an output limit that is power allowed for discharging the power storage means is set, and the power limit determination means determines that the required engine power is greater than or equal to the power limit determination threshold. Further comprising output limit setting means for temporarily increasing the output limit sometimes.
The control means causes the internal combustion engine and the electric motor to obtain a traveling torque based on the required torque set by the required torque setting means within a range of the output restriction set by the output restriction setting means. Hybrid vehicle to control. In the hybrid vehicle according to any one of claims 1 to 3,
The hybrid vehicle in which the power limit determination threshold is set to increase as the temperature of the internal combustion engine increases. In the hybrid vehicle according to any one of claims 1 to 4,
The power limit execution time is set to a first time that tends to be shorter as the temperature of the internal combustion engine is higher, and to be shorter as the required engine power set by the required engine power setting means is larger. A hybrid vehicle that is the shorter of the second time. In the hybrid vehicle according to any one of claims 1 to 5,
A second electric motor capable of inputting and outputting power and capable of exchanging electric power with the power storage means;
A first element connected to an output shaft of the internal combustion engine, a second element connected to a rotating shaft of the second electric motor, and a third element connected to the drive shaft connected to driving wheels And a planetary gear mechanism configured so that these three elements can differentially rotate with respect to each other.
The electric motor can output power to the drive shaft,
The control means is a hybrid vehicle that controls the internal combustion engine, the electric motor, and the second electric motor so as to obtain a running torque based on the required torque set by the required torque setting means. A control method for a hybrid vehicle, comprising: an internal combustion engine capable of outputting traveling power to a drive shaft; an electric motor capable of outputting traveling power to the drive shaft; and a storage means capable of exchanging electric power with the motor. There,
(A) a step of setting a required torque required for traveling according to a driver's driving force request operation;
(B) setting required engine power, which is power required for the internal combustion engine, based on the required torque set in step (a);
(C) The required engine power set in step (b) after the start of the internal combustion engine in response to the first start request after the start of traveling is equal to or greater than a power limit determination threshold based on the temperature of the internal combustion engine. Determining whether or not,
(D) When it is determined in step (c) that the required engine power is less than the power limit determination threshold, the internal combustion engine outputs power based on the required engine power set in step (b). In addition, the internal combustion engine and the electric motor are controlled so that a traveling torque based on the required torque set in step (a) is output to the drive shaft, and in step (c), the required engine power is When it is determined that the power limit determination threshold is exceeded, the internal combustion engine is independently operated for a predetermined power limit execution time, and the driving torque based on the required torque set in step (a) is driven. Controlling the internal combustion engine and the electric motor to be output to a shaft ;
A control method for a hybrid vehicle including:

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