JP2022137545A - Hybrid automobile - Google Patents

Abstract

To suppress the combustion of an engine from deteriorating.SOLUTION: When a transition from idling-on to idling-off is made, an integration term at the time of an idling turn-on before transition to the idling-off is stored. Then, upon idling-on, an ignition timing of the engine is controlled using the stored integration term at the idling turn-on. When a transition from the idling-off to an idling-on is made, an integration term at turning off of idling before transition to the idling-off is stored, and then upon idling-off, the ignition timing of the engine is controlled using the stored integration term at turning off the idling. This makes it possible to suppress the combustion of the engine from deteriorating.SELECTED DRAWING: Figure 5

Description

The present invention relates to a hybrid vehicle including an engine and a motor.

Conventionally, hybrid vehicles of this type have been proposed that include an engine and a motor (see, for example, Patent Document 1). The engine outputs power for running. The motor inputs and outputs power to the output shaft of the engine. In this vehicle, during a request for warm-up of the catalyst, catalyst warm-up control is executed to retard the ignition timing of the engine while feedback-controlling the rotation speed of the engine by the motor. Then, when the output of the motor exceeds a predetermined upper limit value during catalyst warm-up control, the amount of retardation of the ignition timing is reduced. This prevents engine misfires.

Japanese Patent Application Laid-Open No. 2003-214308

In the hybrid vehicle described above, in order to suppress the deterioration of engine combustion, the ignition timing of the engine is adjusted to the ignition timing during idling off during load operation of the engine during catalyst warm-up control. It is conceivable to control the engine so that the second ignition timing is different from the first ignition timing. It is recognized as an important issue to suppress deterioration of engine combustion by appropriately changing the ignition timing when shifting from idle-on to idle-off or vice-versa.

A main object of the hybrid vehicle of the present invention is to suppress deterioration of engine combustion.

The hybrid vehicle of the present invention employs the following means in order to achieve the above main object.

The hybrid vehicle of the present invention is
an engine fitted with a purification device having a purification catalyst;
a motor capable of inputting and outputting power to the output shaft of the engine;
When a catalyst warm-up request for warming up the purification catalyst is made, the engine ignition timing is controlled while feedback-controlling the rotation speed of the engine by the motor during idling off when the engine is operated under load. is the first ignition timing for facilitating warm-up of the engine, and when the engine is idle-on, the motor is controlled with a torque command of value 0, and the a control device for controlling the engine such that the ignition timing of the engine becomes a second ignition timing different from the first ignition timing and the rotation speed of the engine becomes an idling rotation speed;
A hybrid vehicle comprising
The control device is
When the catalyst warm-up request is made,
feedback-controlling the ignition timing of the engine using an integral term calculated using the torque of the motor when the engine is idle-off and a condition for deterioration of combustion of the engine based on the torque of the motor is satisfied;
Feedback control of ignition timing of the engine using an integral term calculated using the engine speed when the engine is idling on and a condition for deterioration of combustion of the engine based on the engine speed is satisfied. death,
When shifting from the idle-on to the idle-off, the integral term at the time of the idle-on before shifting to the idle-off is stored, and thereafter, when the idle-on is changed, the stored idle-on time controlling the ignition timing of the engine using the integral term of
When shifting from the idle-off state to the idle-on state, the integral term at the idle-off state before shifting to the idle-on state is stored. controlling the ignition timing of the engine using the integral term of
This is the gist of it.

In the hybrid vehicle of the present invention, when the catalyst warm-up request is made, when the idle is off and the engine combustion deterioration condition based on the motor torque is satisfied, the torque of the motor is used for calculation. feedback control of the ignition timing of the engine using the integral term, and the integral term calculated using the engine speed when the engine is idle and when the engine combustion deterioration condition based on the engine speed is satisfied. is used to control the ignition timing of the engine. When shifting from idling on to idling off, the integral term at idling on before shifting to idling off is stored, and when idling is turned on after that, the stored integral term at idling on is used. control the ignition timing of the engine. Furthermore, when shifting from idling off to idling on, the integral term at idling off before shifting to idling on is stored, and after that, when idling off, the stored integral term at idling off is used. control the ignition timing of the engine. Feedback control of the ignition timing of the engine is performed using an integral term calculated using different parameters for idling off and idling on when conditions for deterioration of engine combustion are satisfied. Therefore, when shifting from idling off to idling on, or vice versa, the integral term suddenly changes, making it impossible to control proper ignition timing, and the combustion state of the engine deteriorates. be. In the present invention, when shifting from idling on to idling off, the integral term at idling on before shifting to idling off is stored, and after that, when idling is on, the stored integral term at idling on is stored. is used to control the ignition timing of the engine, and when shifting from idle-off to idle-on, the integral term at idle-off before shifting to idle-on is stored. By controlling the ignition timing of the engine using the integral term during idle-off, sudden changes in the integral term when shifting from idle-on to idle-off or from idle-on to idle-off are suppressed. As a result, deterioration of engine combustion can be suppressed.

1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 equipped with a control device for an internal combustion engine according to an embodiment of the present invention; FIG. 2 is a configuration diagram showing an outline of the configuration of an engine 22; FIG. 4 is a flowchart showing an example of a first ignition timing setting routine executed by HVECU 70; 4 is a flowchart showing an example of a second ignition timing setting routine executed by HVECU 70; 4 is a flowchart showing an example of a transition ignition timing setting routine executed by an HVECU 70; FIG. 3 is an explanatory diagram for explaining an example of changes over time of an idling state, a rotation speed Ne of an engine 22, a motor torque Tm1, an integral term Ion stored in a RAM, and an integral term Ioff;

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

FIG. 1 is a configuration diagram showing the outline of the configuration of a hybrid vehicle 20 equipped with an internal combustion engine control device according to an embodiment of the present invention. FIG. 2 is a configuration diagram showing an outline of the configuration of the engine 22. As shown in FIG. A hybrid vehicle 20 of the embodiment, as shown in FIG. ) 70.

The engine 22 is configured as an internal combustion engine that outputs power using gasoline, light oil, or the like as fuel. As shown in FIG. 2 , the engine 22 sucks air cleaned by an air cleaner 122 into an intake pipe 123 and passes it through a throttle valve 124 and a surge tank 125 . Fuel is injected from the fuel injection valve 126 to mix air and fuel. Then, the engine 22 sucks this air-fuel mixture into the combustion chamber 129 through the intake valve 128, and the electric spark generated by the ignition plug 130 causes the air-fuel mixture to explode and burn. The reciprocating motion of the piston 132 pushed down by the energy of this explosive combustion is converted into rotational motion of the crankshaft 26 . The exhaust that is discharged from the combustion chamber 129 to the exhaust pipe 134 via the exhaust valve 133 is discharged to the outside air via the purification device 136 . The purification devices 136 each have a purification catalyst (three-way catalyst) 136a that purifies harmful components such as carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) in the exhaust.

The operation of the engine 22 is controlled by an engine electronic control unit (hereinafter referred to as “engine ECU”) 24 . Although not shown, the engine ECU 24 is configured as a microprocessor centered on a CPU. In addition to the CPU, the engine ECU 24 includes a ROM for storing processing programs, a RAM for temporarily storing data, an input/output port, and a communication port. Prepare.

Signals from various sensors necessary for controlling the operation of the engine 22 are input to the engine ECU 24 through an input port. Signals input to the engine ECU 24 include, for example, a crank angle θcr from a crank position sensor 140 that detects the rotational position of the crankshaft 26 of the engine 22, and a water temperature sensor 142 that detects the temperature of the cooling water of the engine 22. A cooling water temperature Tw can be mentioned. In addition, the cam position θca from a cam position sensor 144 that detects the rotational positions of the intake camshaft that opens and closes the intake valve 128 and the exhaust camshaft that opens and closes the exhaust valve 133 can also be used. Furthermore, the throttle opening TH from the throttle valve position sensor 124a that detects the position of the throttle valve 124, the intake air amount Qa from the air flow meter 148 attached to the intake pipe 123, and the temperature sensor 149 attached to the intake pipe 123 The intake air temperature Ta from the intake air and the surge pressure Ps from the pressure sensor 150 attached to the surge tank 125 can also be mentioned. In addition, the detected air-fuel ratio AFu from the upstream air-fuel ratio sensor 152 attached upstream of the purification device 136 of the exhaust pipe 134 and the downstream air-fuel ratio AFu attached downstream of the purification device 136 of the exhaust pipe 134 A detected air-fuel ratio AFd from the fuel ratio sensor 154 can also be mentioned.

Various control signals for controlling the operation of the engine 22 are output from the engine ECU 24 through an output port. Signals output from the engine ECU 24 include, for example, a drive control signal to the throttle motor 124b that adjusts the position of the throttle valve 124, a drive control signal to the fuel injection valve 126, and a control signal to the spark plug 130. can be done.

The engine ECU 24 is connected to the HVECU 70 via a communication port. Engine ECU 24 calculates rotation speed Ne of engine 22 based on crank angle θcr of engine 22 from crank position sensor 140 . In addition, based on the intake air amount Qa from the air flow meter 148 and the rotation speed Ne of the engine 22, the volumetric efficiency (the ratio of the volume of air actually taken in one cycle to the stroke volume of the engine 22 per cycle) KL to calculate

The planetary gear 30 is configured as a single pinion type planetary gear mechanism. The sun gear of the planetary gear 30 is connected to the rotor of the motor MG1. A ring gear of the planetary gear 30 is connected to a drive shaft 36 that is connected to drive wheels 39a and 39b via a differential gear 38. As shown in FIG. A crankshaft 26 of the engine 22 is connected to the carrier of the planetary gear 30 via a damper 28 .

The motor MG1 is configured as, for example, a synchronous generator-motor, and the rotor is connected to the sun gear of the planetary gear 30 as described above. The motor MG2 is configured as, for example, a synchronous generator-motor, and has a rotor connected to the drive shaft 36 . Inverters 41 and 42 are used to drive motors MG1 and MG2 and are connected to battery 50 via power line 54 . The motors MG1 and MG2 are rotationally driven by switching control of a plurality of switching elements (not shown) of the inverters 41 and 42 by a motor electronic control unit (hereinafter referred to as a “motor ECU”) 40 .

Although not shown, the motor ECU 40 is configured as a microprocessor centered on a CPU. In addition to the CPU, the motor ECU 40 includes a ROM for storing processing programs, a RAM for temporarily storing data, an input/output port, and a communication port. Prepare. Signals from various sensors necessary for driving and controlling the motors MG1 and MG2 are input to the motor ECU 40 through input ports. Signals input to the motor ECU 40 include, for example, rotational positions θm1 and θm2 of the rotors of the motors MG1 and MG2 from rotational position sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2, Phase currents Iu1 and Iv1 of each phase of the motor MG1 from current sensors 41a and 41b that detect phase currents flowing in each phase of the motor MG1, and phase currents of the motor MG2 from current sensors that detect phase currents flowing in each phase of the motor MG2 of the phase currents Iu2 and Iv2 can be mentioned. The motor ECU 40 outputs switching control signals to a plurality of switching elements (not shown) of the inverters 41 and 42 through output ports. The motor ECU 40 is connected to the HVECU 70 via a communication port. The motor ECU 40 calculates electrical angles θe1, θe2 and rotational speeds Nm1, Nm2 of the motors MG1, MG2 based on the rotational positions θm1, θm2 of the rotors of the motors MG1, MG2 from the rotational position sensors 43, 44 .

The battery 50 is configured as, for example, a lithium-ion secondary battery or a nickel-hydrogen secondary battery, and is connected to the inverters 41 and 42 via the power line 54 as described above. The battery 50 is managed by a battery electronic control unit (hereinafter referred to as “battery ECU”) 52 .

Although not shown, the battery ECU 52 is configured as a microprocessor centered on a CPU. In addition to the CPU, the battery ECU 52 includes a ROM for storing processing programs, a RAM for temporarily storing data, an input/output port, and a communication port. Prepare. Signals from various sensors necessary for managing the battery 50 are input to the battery ECU 52 through an input port. The signals input to the battery ECU 52 include, for example, the voltage Vb of the battery 50 from the voltage sensor 51a attached between the terminals of the battery 50, and the voltage Vb of the battery 50 from the current sensor 51b attached to the output terminal of the battery 50. Battery current Ib and temperature Tb of battery 50 from temperature sensor 51c attached to battery 50 can be mentioned. The battery ECU 52 is connected to the HVECU 70 via a communication port. The battery ECU 52 calculates the state of charge SOC based on the integrated value of the battery current Ib from the current sensor 51b. The power storage ratio SOC is the ratio of the amount of electric power that can be discharged from the battery 50 to the total capacity of the battery 50 .

Although not shown, the HVECU 70 is configured as a microprocessor centered on a CPU, and in addition to the CPU, includes a ROM for storing processing programs, a RAM for temporarily storing data, an input/output port, and a communication port. . Signals from various sensors are input to the HVECU 70 through input ports. Signals input to the HVECU 70 include, for example, an ignition signal from an ignition switch 80 and a shift position SP from a shift position sensor 82 that detects the operating position of a shift lever 81 . Further, the accelerator opening Acc from an accelerator pedal position sensor 84 that detects the amount of depression of the accelerator pedal 83, the brake pedal position BP from a brake pedal position sensor 86 that detects the amount of depression of the brake pedal 85, and the vehicle speed sensor 88. Vehicle speed V can also be mentioned. The HVECU 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via communication ports, as described above.

The hybrid vehicle 20 of the embodiment configured in this way can be operated in an electric driving mode (EV driving mode) in which the engine 22 is not operated, or in a hybrid driving mode (HV driving mode) in which the engine 22 is operated. run.

In the EV running mode, the HVECU 70 first sets a required torque Td* required for running (required for the drive shaft 36) based on the accelerator opening Acc and the vehicle speed V. FIG. Subsequently, the torque command Tm1* for the motor MG1 is set to 0, and the torque command Tm2* for the motor MG2 is set so that the required torque Td* is output to the drive shaft 36. Commands Tm1* and Tm2* are sent to the motor ECU 40. Motor ECU 40 performs switching control of a plurality of switching elements of inverters 41 and 42 so that motors MG1 and MG2 are driven by torque commands Tm1* and Tm2*.

In the HV running mode, the HVECU 70 first sets the required torque Td* as in the EV running mode. Subsequently, the required power Pd* required for running is calculated by multiplying the required torque Td* by the number of revolutions Nd of the drive shaft 36, and the required charging/discharging power Pb* of the battery 50 (discharge from the battery 50) is calculated from the required power Pd*. is a positive value) is subtracted to calculate the required power Pe* required for the engine 22 . Here, as the rotational speed Nd of the drive shaft 36, for example, the rotational speed Nm2 of the motor MG2 or the rotational speed obtained by multiplying the vehicle speed V by a conversion factor is used. Then, the target rotational speed Ne* and the target torque Te* of the engine 22 are set so that the required power Pe* is output from the engine 22 and the required torque Td* is output to the drive shaft 36 . Furthermore, the torque command Tm1* for the motor MG1 is set so that the rotation speed Ne of the engine 22 is feedback-controlled by the motor MG1 so that the rotation speed Ne of the engine 22 becomes the target rotation speed Ne*, and the required torque Td is set. A torque command Tm2* for the motor MG2 is set so that * is output to the drive shaft . Then, the target rotational speed Ne* and the target torque Te* of the engine 22 are transmitted to the engine ECU 24, and torque commands Tm1* and Tm2* of the motors MG1 and MG2 are transmitted to the motor ECU 40. The engine ECU 24 performs intake air amount control, fuel injection control, ignition control, etc. of the engine 22 so that the engine 22 is operated based on the target rotational speed Ne* and the target torque Te*. The control of motors MG1 and MG2 (inverters 41 and 42) by motor ECU 40 has been described above.

Next, the operation of the hybrid vehicle 20 of the embodiment configured as described above, in particular, the operation of warming up the purification catalyst 136a of the engine 22 will be described.

In the hybrid vehicle 20 of the embodiment, when the temperature of the purification catalyst 136a of the engine 22 is below a predetermined temperature (for example, 350° C., 400° C., 450° C., etc.) during HV driving, the purification catalyst 136 a is warmed up. The following control is executed when a catalyst warm-up request is made.

When the catalyst warm-up request is issued and the engine 22 is operated under load such as when the required power Pe* is equal to or greater than 0, the target rotation speed Ne* of the engine 22 is set in the same manner as the above-described control during HV running. , the target torque Te* and the torque commands Tm1* and Tm2* of the motors MG1 and MG2 are set. Then, a target ignition timing Tf* is set by a first ignition timing setting routine, which will be described later. The target rotation speed Ne*, target torque Te*, and target ignition timing Tf* of the engine 22 are transmitted to the engine ECU 24 . The torque commands Tm1* and Tm2* for the motors MG1 and MG2 are transmitted to the motor ECU 40. The engine ECU 24 performs intake air amount control, fuel injection control, ignition control, etc. of the engine 22 so that the engine 22 is operated based on the received target rotational speed Ne*, target torque Te*, and target ignition timing Tf*. . Motor ECU 40 controls inverters 41 and 42 as described above. That is, when the engine 22 is operated under load, the motor MG1 feedback-controls the rotational speed Ne of the engine 22 with the engine 22 .

FIG. 3 is a flow chart showing an example of a first ignition timing setting routine executed by the HVECU 70. As shown in FIG. The first ignition timing setting routine is repeatedly executed by the CPU (not shown) of the HVECU 70 when the engine 22 is under load when a catalyst warm-up request is made.

When the first ignition timing setting routine is executed, the CPU of the HVECU 70 executes processing for inputting the phase currents Iu1 and Iv1 of the motor MG1 (step S100). The phase currents Iu1 and Iv1 detected by the current sensors 41a and 41b are inputted through the motor ECU 40 by communication.

Subsequently, a motor torque Tm1, which is the torque output from the motor MG1, is set based on the input phase currents Iu1 and Iv1 (step S110). This setting predetermines the relationship between the phase currents Iu1 and Iv1 and the output torque output from the motor MG1 as the first relationship. The output torque derived from the relationship is set as the motor torque Tm1.

When the motor torque Tm1 is set, a value obtained by subtracting the motor torque Tm1 (previous Tm1) set when this routine was executed last time from the motor torque Tm1 is set as the torque change amount ΔTm1 (step S120), and the torque change amount ΔTm1 is It is determined whether or not it is equal to or less than the threshold dtm1ref (step S130). The threshold dtm1ref is a threshold for determining whether or not the torque output from the motor MG1 has decreased significantly, and is set as a negative value. When the combustion state of the engine 22 deteriorates, the torque output from the engine 22 is greatly reduced, so the output torque of the motor MG1 that feedback-controls the rotational speed Ne of the engine 22 is also greatly reduced. Therefore, when the output torque of the motor MG1 is greatly reduced, it is considered that the combustion state of the engine 22 is deteriorating. Therefore, step S130 is a process of determining whether or not a condition for deterioration of combustion as a condition for deterioration of the combustion state of the engine 22 is satisfied.

When the torque change amount ΔTm1 is greater than the threshold value dtm1ref in step S130, it is determined that the condition for deterioration of combustion is not satisfied, and the target ignition timing Tf* of the engine 22 is set to the most retarded angle Tl (step S140). The timing Tf* is transmitted to the engine ECU 24 (step S160), and the first ignition timing setting routine ends. The most retarded angle Tl in step S140 is the latest timing (timing) within a predetermined range of possible ignition timings of the engine 22 . Upon receiving the target ignition timing Tf*, the engine ECU 24 controls the spark plug 130 so that ignition is performed at the target ignition timing Tf* (the most retarded angle Tl) (the ignition timing becomes the target ignition timing Tf*). Thus, by setting the ignition timing to the most retarded angle Tl, the purification catalyst 136a can be warmed up.

When the torque change amount ΔTm1 is equal to or less than the threshold value dtm1ref in step S130, it is determined that the condition for deterioration of combustion is satisfied, and the target ignition timing Tf* at the time when this routine was executed last time and the set torque command Tm1* Target ignition timing Tf* is set using the motor torque Tm1 set in step S110 and the following equation (1) (step S150). In equation (1), the second term is a proportional term in feedback control of the ignition timing of engine 22 to bring motor torque Tm1 close to torque command Tm1*. "Kp1" is the gain of the proportional term. The third term is an integral term in feedback control of the ignition timing of the engine 22 . "Ki1" is the gain of the integral term.

Tf*=previous Tf*+Kp1・(Tm1*-Tm1)+Ki1・∫(Tm1*-Tm1)dt・・・(1)

Subsequently, the second term of equation (1) is stored in a RAM (not shown) as a proportional term Poff, and the third term is stored in a RAM (not shown) as an integral term Ioff (step S160). (step S170) to end the first ignition timing setting routine. In step S160, when the proportional term Poff and integral term Ioff are already stored in the RAM, the stored proportional term Poff and integral term Ioff are overwritten with the proportional term Poff and integral term Ioff in step S160. Therefore, the RAM stores the last proportional term Poff and integral term Ioff set before shifting from idle-off to idle-on. Upon receiving the target ignition timing Tf* in step S170, the engine ECU 24 controls the spark plug 130 so that ignition is performed at the target ignition timing Tf* (the ignition timing becomes the target ignition timing Tf*). Through such control, deterioration of combustion in the engine 22 can be suppressed.

When the catalyst warm-up request is made and the required power Pe* is 0 and the engine 22 is idled, the torque command Tm1* for the motor MG1 is set to 0. Then, the torque command Tm2* for the motor MG2 is set so that the required torque Td* is output to the drive shaft . The torque commands Tm1* and Tm2* for the motors MG1 and MG2 are transmitted to the motor ECU 40. Motor ECU 40 controls inverters 41 and 42 as described above. Then, the target ignition timing Tf* of the engine 22 is set by a second ignition timing setting routine, which will be described later. Then, the ignition plug 130 is controlled so as to ignite at the target ignition timing Tf* (so that the ignition timing becomes the target ignition timing Tf*), and the engine 22 is idled at a predetermined idle rotation speed Nidl (independent operation). The intake air amount control of the engine 22, fuel injection control, and the like, excluding the ignition control of the engine 22, are performed so that the engine 22 can be operated.

FIG. 4 is a flow chart showing an example of a second ignition timing setting routine executed by the HVECU 70. As shown in FIG. The second ignition timing setting routine is repeatedly executed by the CPU (not shown) of the HVECU 70 when the engine 22 is idling when a catalyst warm-up request is made.

When the second ignition timing setting routine is executed, the CPU of the HVECU 70 executes processing for inputting the rotational speed Ne of the engine 22 (step S200). The rotational speed Ne is calculated by the engine ECU 24 and inputted through communication.

Subsequently, the rotation speed change amount ΔNe is set to a value obtained by subtracting the rotation speed Ne input when this routine was executed last time from the input rotation speed Ne (step S210). It is determined whether or not there is (step S220). The threshold dNeref is a threshold for determining whether or not the rotational speed Ne of the engine 22 has decreased significantly, and is set as a negative value. If the combustion state of the engine 22 deteriorates while the engine 22 is idling, the rotational speed Ne of the engine 22 decreases. Therefore, step S220 is a process of determining whether or not a condition for deterioration of combustion as a condition for deterioration of the combustion state of the engine 22 is satisfied.

When the rotational speed change amount ΔNe is greater than the threshold value dNeref in step S220, it is determined that the condition for deterioration of combustion is not satisfied, and the target ignition timing Tf* of the engine 22 is advanced from the maximum retardation Tl (maximum retardation Tl (step S230), transmits the target ignition timing Tf* to the engine ECU 24 (step S250), and ends the second ignition timing setting routine. . The predetermined timing Ta is an ignition timing predetermined as an ignition timing when the engine 22 is idling. Upon receiving the target ignition timing Tf*, the engine ECU 24 controls the spark plug 130 so that ignition occurs at the target ignition timing Tf* (predetermined timing Ta) (the ignition timing becomes the target ignition timing Tf*). Thus, by setting the ignition timing to the predetermined timing Ta, the purification catalyst 136a can be warmed up while the engine 22 is idling.

When the rotation speed change amount ΔNe is equal to or less than the threshold value dNeref in step S220, it is determined that the condition for deterioration of combustion is satisfied, and the target ignition timing Tf* and the idle rotation speed Nidl at the time when this routine was executed last time and in step S200 A target ignition timing Tf* is set using the inputted engine 22 speed Ne and the following equation (2) (step S240). In the equation (2) of step S240, the second term is a proportional term in the ignition timing feedback control for bringing the rotation speed Ne of the engine 22 closer to the idle rotation speed Nidl. "Kp2" is the gain of the proportional term. The third term is an integral term in the ignition timing feedback control for bringing the rotation speed Ne of the engine 22 closer to the idle rotation speed Nidl. "Ki2" is the gain of the integral term.

Tf*=previous Tf*+Kp2・(Nidl-Ne)+Ki2・∫(Nidl-Ne)dt (2)

Subsequently, the second term of equation (2) is stored in a RAM (not shown) as a proportional term Pon, and the third term is stored in a RAM (not shown) as an integral term Ion (step S250). (step S260) to terminate the second ignition timing setting routine. In step S250, when the proportional term Pon and the integral term Ion are already stored, the already stored proportional term Pon and integral term Ion are overwritten with the new proportional term Pon and integral term Ion. Therefore, the RAM stores the last set proportional term Pon and integral term Ion. Having received the target ignition timing Tf* in step S260, the engine ECU 24 controls the spark plug 130 so that ignition is performed at the target ignition timing Tf* (the ignition timing becomes the target ignition timing Tf*). Through such control, the engine 22 can be idling while suppressing deterioration of combustion in the engine 22 .

Next, a description will be given of the operation when control is shifted between idling on and idling off when a catalyst warm-up request is made. FIG. 5 is a flow chart showing an example of the transition ignition timing setting routine executed by the HVECU 70. As shown in FIG. The transition ignition timing setting routine is executed by the CPU of the HVECU 70 when shifting from idle-off to idle-on or from idle-on to idle-off when a catalyst warm-up request is made.

When the transition ignition timing setting routine is executed, the CPU of the HVECU 70 executes a process of determining whether or not there is a transition from idling on to idling off (step S300). When the transition is not from idle-on to idle-off, that is, when the transition is from idle-off to idle-on, the proportional term Poff and the integral term Ion stored in a RAM (not shown) are input (step S310). The proportional term Poff is the value last stored during idle-off, that is, the proportional term Poff at idle-off immediately before entering idle-on. The integral term Ion is the integral term Ion last stored in the RMA at the previous idle-on.

When the proportional term Poff and the integral term Ion are input in this manner, the input proportional term Poff and integral term Ion, the target ignition timing Tf* (previous Tf*) set immediately before this routine is executed, and the following equation (3) are obtained. is used to set the target ignition timing Tf* (step S320), the target ignition timing Tf* is transmitted to the engine ECU 24 (step S350), and the transition ignition timing setting routine ends. Having received the target ignition timing Tf* in step S350, the engine ECU 24 controls the spark plug 130 so that ignition is performed at the target ignition timing Tf* (the ignition timing becomes the target ignition timing Tf*). Therefore, when the idle-off state changes to the idle-on state, the ignition timing of the engine 22 is controlled using the stored integral term Ion at the end of the previous idle-on state.

Tf*=previous Tf*+Poff+Ion (3)

At the time of transition from idling ON to idling OFF at step S300, the proportional term Pon and the integral term Ioff stored in the RAM (not shown) are input (step S330). The proportional term Pon is the value last stored when the engine is idling on, that is, the proportional term Pon at idling on just before idling off. The integral term Ioff is the last integral term Ioff stored at the previous idle-off.

When the proportional term Pon and the integral term Ioff are input in this way, the input proportional term Pon and integral term Ioff, the target ignition timing Tf* (previous Tf*) set immediately before this routine is executed, and the following equation (4) are obtained. is used to set the target ignition timing Tf* (step S340), the target ignition timing Tf* is transmitted to the engine ECU 24 (step S350), and the transition ignition timing setting routine ends. Having received the target ignition timing Tf* in step S350, the engine ECU 24 controls the spark plug 130 so that ignition is performed at the target ignition timing Tf* (the ignition timing becomes the target ignition timing Tf*). Therefore, when the idle-on state changes to the idle-off state, the ignition timing of the engine 22 is controlled using the stored integral term Ioff at the end of the previous idle-off state.

Tf*=previous Tf*+Pon+Ioff (4)

FIG. 6 is an explanatory diagram for explaining an example of change over time of the idling state, the rotation speed Ne of the engine 22, the motor torque Tm1, the integral term Ion, and the integral term Ioff stored in the RAM. In the figure, the region surrounded by the broken-line square is the period during which the condition for deterioration of combustion is satisfied. The area enclosed by the dashed circle contains the integral terms Ion and Ioff stored in the RAM at the end of idle ON and idle OFF.

As shown in the figure, when the idle-off shifts to the idle-on (time t2), the integral term Ion (time t1 ) is used to set the target ignition timing Tf*. When the idle-on shifts to off (time t3), instead of the integral term Ion at the idle-on immediately before the idle-off, the integral term Ioff at the previous idle-off (integral term immediately before the time t2). is used to set the target ignition timing Tf*. The reason for setting the target ignition timing Tf* in this way is as follows.

In the first ignition timing setting routine shown in FIG. 3 and the second ignition timing setting routine shown in FIG. 4, different parameters are set depending on whether the engine 22 is idling off or idling on when the combustion deterioration condition of the engine 22 is satisfied. Feedback control of the ignition timing of the engine 22 is performed using the integral term calculated using . Therefore, when shifting from idle-off to idle-on or from idle-on to idle-off, the integral term of the feedback control changes suddenly, making it impossible to control the proper ignition timing, and the combustion state of the engine 22 deteriorates. It may get worse. In the embodiment, when shifting from idling on to idling off, the integral term Ion at idling on before shifting to idling off is stored, and after that, when idling on, the stored integral at idling on is stored. The term Ion is used to control the ignition timing of the engine 22 . Then, when shifting from idle-off to idle-on, the integral term Ioff at idle-off before shifting to idle-on is stored, and after that, when the idle is turned off, the stored integral term Ioff at idle-off is stored. is used to control the ignition timing of the engine 22 . This makes it possible to suppress sudden changes in the integral term when shifting from idle on to idle off or from idle on to idle off, and when shifting from idle on to idle off or vice versa. Furthermore, deterioration of combustion in the engine 22 can be suppressed.

According to the hybrid vehicle 20 of the embodiment described above, when the catalyst warm-up request is made, the motor torque Tm is feedback control of the ignition timing of the engine 22 using the integral term Ioff calculated using The ignition timing of the engine 22 is feedback-controlled using the integral term Ion calculated using the rotational speed of , and when shifting from idle-on to idle-off, the integral term Ion at idle-on before shifting to idle-off is set to After that, when the idle is turned on, the stored integral term Ion at idle is used to control the ignition timing of the engine 22, and when the idle is shifted from the idle off to the idle on, the shift is made to the idle on. By storing the previous idle-off integral term Ioff, and thereafter when idling off, the ignition timing of the engine 22 is controlled using the stored idle-off integral term Ioff. Aggravation of combustion can be suppressed.

According to the hybrid vehicle 20 of the embodiment, in step S150 of the first ignition timing setting routine of FIG. 3 and step S240 of the second ignition timing setting routine of FIG. is set using However, the target ignition timing Tf* may be set using only the integral term without using the proportional term.

In the embodiment, the present invention is applied to a hybrid vehicle 20 having an engine 22, planetary gears 30, and motors MG1 and MG2. However, the present invention may be applied to a so-called one-motor hybrid vehicle having an engine and one motor. Furthermore, it may be applied to hybrid vehicles different from automobiles, such as trains and construction vehicles.

The correspondence relationship between the main elements of the embodiments and the main elements of the invention described in the column of Means for Solving the Problems will be described. In the embodiment, the engine 22 corresponds to the "engine", the motor MG1 corresponds to the "motor", and the engine ECU 24, the motor ECU 40 and the HVECU 70 correspond to the "control device".

Note that the correspondence relationship between the main elements of the examples and the main elements of the invention described in the column of Means for Solving the Problems is the Since it is an example for specifically explaining the mode for solving the problem, it does not limit the elements of the invention described in the column of the means for solving the problem. That is, the interpretation of the invention described in the column of Means to Solve the Problem should be made based on the description in that column, and the Examples are based on the description of the invention described in the column of Means to Solve the Problem. This is only a specific example.

Although the embodiments for carrying out the present invention have been described above, the present invention is not limited to such embodiments at all, and can be modified in various forms without departing from the scope of the present invention. Of course, it can be implemented.

INDUSTRIAL APPLICABILITY The present invention is applicable to the hybrid vehicle manufacturing industry and the like.

20 hybrid vehicle 22 engine 24 engine ECU 26 crankshaft 28 damper 30 planetary gear 36 drive shaft 38 differential gear 39a, 39b drive wheel 40 motor ECU 41, 42 inverter 41a, 41b, 51b current Sensors 43, 44 Rotation Position Sensor 50 Battery 51a Voltage Sensor 51c Temperature Sensor 52 Battery ECU 54 Power Line 70 HVECU 80 Ignition Switch 81 Shift Lever 82 Shift Position Sensor 83 Accelerator Pedal 84 Accelerator Pedal position sensor 85 brake pedal 86 brake pedal position sensor 88 vehicle speed sensor 122 air cleaner 123 intake pipe 124 throttle valve 124a throttle valve position sensor 124b throttle motor 125 surge tank 126 fuel injection valve 128 intake valve, 129 combustion chamber, 130 spark plug, 132 piston, 133 exhaust valve, 134 exhaust pipe, 136 purification device, 136a purification catalyst, 140 crank position sensor, 142 water temperature sensor, 144 cam position sensor, 148 air flow meter, 149 temperature sensor , 150 pressure sensor, 152 upstream air-fuel ratio sensor, 154 downstream air-fuel ratio sensor, MG1, MG2 motors.

Claims (1)

an engine fitted with a purification device having a purification catalyst;
a motor capable of inputting and outputting power to the output shaft of the engine;
When a catalyst warm-up request for warming up the purification catalyst is made, the engine ignition timing is controlled while feedback-controlling the rotation speed of the engine by the motor during idling off when the engine is operated under load. is the first ignition timing for facilitating warm-up of the engine, and when the engine is idle-on, the motor is controlled with a torque command of value 0, and the a control device for controlling the engine such that the ignition timing of the engine becomes a second ignition timing different from the first ignition timing and the rotation speed of the engine becomes an idling rotation speed;
A hybrid vehicle comprising
The control device is
When the catalyst warm-up request is made,
feedback-controlling the ignition timing of the engine using an integral term calculated using the torque of the motor when the engine is idle-off and a condition for deterioration of combustion of the engine based on the torque of the motor is satisfied;
When the engine is idling on and the condition for deterioration of combustion based on the engine speed is satisfied, feedback control of the ignition timing of the engine is performed using the integral term calculated using the engine speed. ,
When shifting from the idle-on to the idle-off, the integral term at the time of the idle-on before shifting to the idle-off is stored, and thereafter, when the idle-on is changed, the stored idle-on time controlling the ignition timing of the engine using the integral term of
When shifting from the idle-off state to the idle-on state, the integral term at the idle-off state before shifting to the idle-on state is stored. controlling the ignition timing of the engine using the integral term of
hybrid car.

Images