JP7360804B2 - Vehicle control method and vehicle - Google Patents

Description

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

Patent Document 1 discloses a technique in which a large amount of EGR (exhaust gas recirculation) is introduced during a steady operation region, and the throttle valve opening is corrected by the amount of torque reduction in the internal combustion engine due to the large amount of EGR. There is.

Japanese Patent Application Publication No. 7-158514

In vehicles, there is a high demand for improving fuel efficiency in order to reduce environmental load, etc., and diluted combustion can be said to be a combustion method for internal combustion engines that is effective in improving fuel efficiency. However, in diluted combustion in which the dilution ratio, that is, the gas-fuel ratio (G/F) is increased, the laminar flow combustion speed is slow, so combustion deteriorates. For this reason, it is necessary to set combustion in consideration of variations in the dilution rate, etc., but variations in the dilution rate become large and affect combustion, especially during transient operation of the internal combustion engine. For example, if a combustion limit dilution rate is set during transient operation, there is a risk that combustion stability will deteriorate and misfires may occur due to variations in not only the dilution rate but also the intake air of the internal combustion engine.

The present invention has been made in view of the above problems, and an object of the present invention is to improve diluted combustion performed in an internal combustion engine during transient operation and to improve fuel efficiency.

A vehicle control method according to an aspect of the present invention includes: an internal combustion engine that is operated by igniting a diluted fuel obtained by diluting a fuel gas with a non-fuel gas; a generator that generates electricity using the driving force of the internal combustion engine; Applies to vehicles equipped with The control method determines whether operating conditions correspond to steady operating conditions or transient operating conditions during operation of the internal combustion engine by spark ignition. When the operating conditions correspond to steady operating conditions, the internal combustion engine is operated under a predetermined dilution rate and the ignition timing of the minimum advance value that provides the best torque according to the predetermined dilution rate . On the other hand, when the operating conditions correspond to transient operating conditions, the internal combustion engine is operated with a dilution rate lower than the predetermined dilution rate and an ignition timing advanced from the ignition timing under steady-state operating conditions. At the same time, the surplus output of the internal combustion engine generated due to the decrease in dilution rate is recovered by power generation by the generator . Furthermore, when the operating conditions are switched from steady operating conditions to transient operating conditions, the dilution rate is reduced prior to advancing the ignition timing.

According to another aspect of the present invention, a vehicle is provided that corresponds to the vehicle control method described above.

According to these aspects, since the dilution rate is lowered during transient operation than during steady operation, combustion stability can be maintained without causing misfire, and combustion can be improved. Furthermore, when the dilution rate is lowered, the torque of the internal combustion engine increases if the throttle opening is not adjusted accordingly.According to these aspects, the surplus output of the internal combustion engine is recovered and used by power generation. can. Therefore, during transient operation, dilution combustion performed in the internal combustion engine can be improved and fuel efficiency can be improved.

1 is a diagram showing main parts of a vehicle. 1 is a diagram showing a power train of a vehicle. FIG. 2 is a flowchart illustrating an example of control performed by a controller. FIG. 2 is a first explanatory diagram regarding the EGR rate and ignition timing during transient operation. FIG. 2 is a second explanatory diagram regarding the EGR rate and ignition timing during transient operation. It is a figure which shows an example of the timing chart corresponding to control of embodiment. FIG. 6 is a timing chart showing details of changes during transition to transient operation.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a diagram showing the main parts of a vehicle. The vehicle includes an internal combustion engine 1, an intake system 10, an exhaust system 20, a supercharger 30, an EGR device 40, and a controller 50.

The intake system 10 includes an intake passage 11, an air flow meter 12, an intake throttle valve 13, a throttle valve 14, an intercooler 15, and a compressor 31. The intake passage 11 allows intake air to be introduced into the internal combustion engine 1 to flow therethrough. In the intake passage 11, an air flow meter 12, an intake throttle valve 13, a compressor 31, a throttle valve 14, and an intercooler 15 are provided in this order from the upstream side.

The air flow meter 12 measures the flow rate of intake air. The intake throttle valve 13 is provided in a portion of the intake passage 11 upstream of a portion to which an EGR passage 41 (described later) is connected. The intake throttle valve 13 increases the amount of exhaust gas recirculated through the EGR passage 41 by decreasing its opening degree.

The throttle valve 14 adjusts the amount of intake air introduced into the internal combustion engine 1. Intercooler 15 cools the supercharged intake air. The compressor 31 is a compressor for the supercharger 30 and compresses intake air.

The exhaust system 20 includes an exhaust passage 21 , upstream catalysts 22 and 23 , a downstream catalyst 24 , a muffler 25 , and a turbine 32 . The exhaust passage 21 allows exhaust gas discharged from the internal combustion engine 1 to circulate. The exhaust passage 21 is provided with a turbine 32, upstream catalysts 22 and 23, a downstream catalyst 24, and a muffler 25 in this order from the upstream side. The upstream catalysts 22, 23 and the downstream catalyst 24 purify the exhaust gas. Silencer 25 reduces exhaust noise. Turbine 32 is the turbine of supercharger 30 and recovers energy from the exhaust gas.

The supercharger 30 compresses intake air and supplies it to the internal combustion engine 1 . The supercharger 30 is a turbocharger and includes a compressor 31, a turbine 32, and a shaft 33. The supercharger 30 is provided in the intake passage 11 and the exhaust passage 21 by providing the compressor 31 and the turbine 32 in the intake passage 11 and the exhaust passage 21, respectively. In the supercharger 30, when the turbine 32 is rotated by exhaust gas, the compressor 31 is rotated via the shaft 33 and compresses intake air. In the compressor 31, a pair of compressor wheels arranged back to back are provided on a shaft 33, and intake air is compressed by the pair of compressor wheels. The turbine 32 is provided with an exhaust bypass passage, and the exhaust bypass passage is provided with a waste gate valve (not shown) that adjusts the flow rate of the flowing exhaust gas.

The EGR device 40 includes an EGR passage 41, an EGR cooler 42, and an EGR valve 43. The EGR device 40 recirculates exhaust gas from a portion of the exhaust passage 21 downstream of the supercharger 30 to a portion of the intake passage 11 upstream of the supercharger 30.

The EGR passage 41 connects the exhaust passage 21 and the intake passage 11. The EGR passage 41 recirculates a portion of the exhaust gas flowing through the exhaust passage 21 to the intake passage 11 as EGR gas. The EGR cooler 42 cools EGR gas flowing through the EGR passage 41. The EGR valve 43 adjusts the flow rate of EGR gas flowing through the EGR passage 41.

The EGR device 40, specifically the EGR passage 41, connects a portion of the exhaust passage 21 downstream of the turbine 32 and a portion of the intake passage 11 upstream of the compressor 31. The EGR passage 41 that connects the intake passage 11 and the exhaust passage 21 in this manner forms an EGR path of LPL, that is, a low pressure loop. More specifically, the EGR passage 41 connects a portion of the exhaust passage 21 between the upstream catalysts 22 and 23 and the downstream catalyst 24 and a portion of the intake passage 11 between the intake throttle valve 13 and the compressor 31.

The controller 50 is an electronic control device, and signals from various sensors and switches such as the air flow meter 12, a crank angle sensor 51, an accelerator opening sensor 52, and an SOC sensor 53 are input to the controller 50. The crank angle sensor 51 generates a crank angle signal at every predetermined crank angle. The crank angle signal is used as a signal representative of the rotational speed NE of the internal combustion engine 1. The accelerator opening sensor 52 detects the amount of depression of the accelerator pedal of the vehicle. The amount of depression of the accelerator pedal is used as a signal representative of the load on the internal combustion engine 1. The SOC sensor 53 detects a state quantity SOC that indicates the state of charge of the battery.

The controller 50 controls the internal combustion engine 1 as well as the intake throttle valve 13, throttle valve 14, and EGR valve 43 based on input signals from the various sensors and switches described above. The controller 50 controls the internal combustion engine 1 by controlling ignition timing and fuel injection amount according to the engine operating state. The engine operating state is, for example, the rotational speed NE or the load.

FIG. 2 is a diagram showing the power train of the vehicle. The vehicle further includes a power generation motor 61, a motor generator (hereinafter referred to as MG) 62, and drive wheels 63. The generator motor 61 is connected to the internal combustion engine 1 via a gear train. The power generation motor 61 constitutes a generator that is driven by the internal combustion engine 1 and generates electricity. The electric power generated by the generator motor 61 can be used to charge the battery and also to drive the MG 62 in a series hybrid mode (hereinafter referred to as series HEV mode) to be described later. The MG 62 is connected to the drive wheels 63 via a gear train or a differential device.

The vehicle configured in this manner is configured as a hybrid vehicle, and has an EV mode and a series HEV mode as driving modes that are set according to the driving state of the vehicle.

The EV mode is an operation mode in which the MG 62 is used as a driving source, that is, a mode in which EV driving is performed. In the EV mode, the internal combustion engine 1 can drive the generator motor 61 to generate electricity for battery charging.

The series HEV mode is an operation mode in which the internal combustion engine 1 drives the generator motor 61 to generate electricity, and the MG 62 is driven by the electric power generated by the generator motor 61, that is, a mode in which series hybrid driving is performed.

MG62 is controlled by an MG controller for controlling MG62. A signal from an MG rotation speed sensor that detects the rotation speed of the MG 62, etc. is input to the MG controller. The controller 50 is connected to the MG controller so as to be able to communicate with each other, and can receive various signals including calculation results and the like from the MG controller. The controller 50 may be configured to control the MG 62 instead of the MG controller.

Incidentally, in vehicles, there is a high demand for improving fuel efficiency in order to reduce environmental load, etc., and in the internal combustion engine 1, EGR combustion is performed by introducing EGR gas. EGR combustion is an example of diluted combustion, and can be said to be a combustion method for the internal combustion engine 1 that is effective in improving fuel efficiency. However, in EGR combustion in which the dilution ratio, that is, the gas-fuel ratio (G/F) is increased, the laminar flow combustion speed is slow, so combustion deteriorates. For this reason, it is necessary to set combustion in consideration of variations in the dilution rate, etc., but the variations in the dilution rate become large and affect combustion, especially during transient operation of the internal combustion engine 1. For example, if a dilution rate for the combustion limit CL, which will be described later, is set during transient operation, not only variations in the dilution rate but also variations in the intake air of the internal combustion engine 1 may cause deterioration of combustion stability or misfire. There are concerns.

In view of such circumstances, in this embodiment, the controller 50 performs the control described below.

FIG. 3 is a flowchart illustrating an example of control performed by the controller 50. The controller 50 is configured to include a control section by being programmed to execute the processing of this flowchart. The controller 50 can perform the process of this flowchart when the internal combustion engine 1 is operating in electric power generation mode in the EV mode. The controller 50 can repeatedly execute the process shown in this flowchart.

In step S1, the controller 50 determines whether a switching condition for the operating conditions of the internal combustion engine 1 is satisfied. The operating conditions of the internal combustion engine 1 that drives the generator motor 61 are switched depending on, for example, the state quantity SOC and the accelerator opening. If the determination in step S1 is negative, the process ends once. If an affirmative determination is made in step S1, the process proceeds to step S2.

In step S2, the controller 50 issues an instruction to reduce the opening degree of the EGR valve 43. As a result, the amount of exhaust gas, that is, EGR gas, recirculated to the internal combustion engine 1 decreases, so the EGR rate decreases and the dilution rate of EGR combustion decreases. The EGR rate corresponds to the dilution rate. Therefore, the dilution rate will be referred to as the EGR rate below.

In step S2, the opening degree of the EGR valve 43 is instructed to gradually decrease to the commanded opening degree. That is, the opening degree of the EGR valve 43 begins to decrease in step S2, and then gradually decreases until it reaches the commanded opening degree. The commanded opening degree of the EGR valve 43 is set to an opening degree that lowers the EGR rate below a predetermined EGR rate α. The predetermined EGR rate α is the EGR rate of EGR combustion performed during steady operation. The EGR rate during transient operation obtained according to the indicated opening degree will be described later. The instruction to reduce the opening degree of the EGR valve 43 is issued earlier than the timing at which the internal combustion engine 1 enters the transient operation in accordance with the establishment of the switching condition.

In step S3, the controller 50 determines whether it is time to switch the operating conditions of the internal combustion engine 1. The switching timing is set to a timing that takes into account the delay until EGR gas is supplied from the EGR valve 43 to the internal combustion engine 1. The switching timing can be set in advance based on the time when the switching conditions of the operating conditions of the internal combustion engine 1 are satisfied. If the determination in step S3 is negative, the process returns to step S3. If the determination in step S3 is affirmative, the process proceeds to step S4.

In step S4, the controller 50 changes the ignition timing. The ignition timing is set to satisfy the minimum advance angle value that corresponds to the EGR rate and that provides the best torque, that is, to satisfy the MBT (Minimum Advance for Best Torque). The EGR rate is the EGR rate during transient operation. Next, the EGR rate and ignition timing during transient operation will be explained using FIGS. 4 and 5.

FIGS. 4 and 5 are explanatory diagrams regarding the EGR rate and ignition timing during transient operation. FIG. 4 shows operating points M corresponding to the EGR rate and the combustion center of gravity, which is a combustion evaluation parameter. FIG. 5 shows thermal efficiency according to the EGR rate. The horizontal axes in FIGS. 4 and 5 are on the same scale.

As shown in FIG. 4, in the internal combustion engine 1, a combustion stability limit line L1, a knock limit line L2, an MBT line L3, and a combustion limit CL are set as shown in the figure, depending on the EGR rate and the combustion center of gravity. The combustion stability limit line L1 constitutes the boundary line of the setting area of the operating point M on the high dilution side, and the knock limit line L2 constitutes the boundary line of the setting area of the operating point M on the low dilution side. The flammability limit CL indicates the flammability limit at the operating point M in the MBT. The thermal efficiency line L4 shown in FIG. 5 is a thermal efficiency line corresponding to the MBT line L3.

The operating point M1 is the operating point M during transient operation, and the operating point M2 is the operating point M during steady operation. Therefore, the EGR rate corresponding to the operating point M1 indicates the EGR rate during transient operation. The operating point M1 is set in a range where the EGR rate is higher than the knock limit line L2. Further, the operating point M1 is set in a range where the EGR rate is lower than the combustion stability limit line L1. That is, the EGR rate during transient operation is set in a range higher than the EGR rate at which knocking occurs, and is set in a range lower than the EGR rate depending on the combustion stability limit.

The operating point M1 has variations VGF1 and VIG1, and the operating point M2 has variations VGF2 and VIG2. The variation VGF1 and the variation VGF2 are variations in the EGR rate, and during transient operation, not only the variation in the EGR rate but also the variation in the intake air of the internal combustion engine 1 are added. Therefore, the variation VGF1 is larger than the variation VGF2. That is, during transient operation, the EGR rate varies more than during steady operation.

Variation VIG1 and variation VIG2 are variations in ignition timing, and as described above, the variation in EGR rate becomes larger during transient operation than during steady operation. Therefore, during transient operation, the appropriate ignition timing also varies more than during steady operation, and the variation VIG1 becomes larger than the variation VIG2.

The operating point M including the operating point M1 and the operating point M2 is set in a region between the combustion stability limit line L1 and the knock limit line L2, including such EGR rate variations and ignition timing variations. Operating point M is further set on MBT line L3. As a result, the ignition timing is set to satisfy the MBT during transient operation, so high thermal efficiency can be obtained.

When the EGR rate is lowered than during steady operation, the torque of the internal combustion engine 1 increases if the opening degree of the throttle valve 14 is not adjusted accordingly. In the internal combustion engine 1, by driving the power generation motor 61 to generate power, surplus output of the internal combustion engine 1 generated due to a decrease in the EGR rate is recovered by power generation by the power generation motor 61.

Returning to FIG. 3, in step S5, the controller 50 determines whether the transient operation ends. Whether or not the transient operation ends can be determined, for example, by determining whether the absolute value of the difference between the rotational speed NE and the target rotational speed according to the operating conditions after switching of the internal combustion engine 1 has become less than a predetermined value ΔNE. The predetermined value ΔNE can be set in advance in consideration of the delay until EGR gas is supplied to the internal combustion engine 1. Whether or not the transient operation ends may be determined, for example, based on the rate of change in the rotational speed NE. If the determination in step S5 is negative, it is determined that the transient operation will not end, and the process returns to step S5. If an affirmative determination is made in step S5, the process proceeds to step S6.

In step S6, the controller 50 issues an instruction to increase the opening degree of the EGR valve 43. This increases the amount of EGR gas, thereby increasing the EGR rate. As a result of setting the predetermined value ΔNE as described above, the instruction to increase the opening degree of the EGR valve 43 is issued before steady operation is started, taking into account the delay until EGR gas is supplied to the internal combustion engine 1. The EGR rate is increased to a predetermined EGR rate α. After step S6, the processing of this flowchart ends once.

FIG. 6 is a diagram showing an example of a timing chart corresponding to the processing of the flowchart shown in FIG. FIG. 7 is a timing chart showing details of changes during transition to transient operation. In FIG. 6, the case where the EGR rate is not changed during transient operation is indicated by a broken line. In FIGS. 6 and 7, the EGR rate indicates the EGR rate at the engine position.

Before timing T1, the internal combustion engine 1 is in steady operation, and the rotational speed NE, torque, and boost pressure are constant. The EGR rate is set to a predetermined EGR rate α. Timing T1 is the switching timing of the operating conditions, and as the operating conditions are switched, the rotational speed NE and torque of the internal combustion engine 1 begin to increase, and the supercharging pressure begins to increase. The EGR rate starts to decrease from timing T1. This will be explained using FIG. 7.

As shown in FIG. 7, the opening degree of the EGR valve 43 begins to decrease before timing T1. That is, in the present embodiment, before the operation of the internal combustion engine 1 is switched from steady operation to transient operation, the EGR valve 43 starts lowering the EGR rate below the predetermined EGR rate α, so that the EGR rate at the engine position is adjusted to the timing T1. I'm trying to make it start to decline. This allows the internal combustion engine 1 to start reducing the EGR rate at timing T1 when the rotational speed NE and torque of the internal combustion engine 1 start to increase.

Returning to FIG. 6, at timing T1, the opening degree of the throttle valve 14 is not adjusted in response to a decrease in the EGR rate. Therefore, surplus torque is generated compared to the case where the EGR rate is not changed. The surplus output resulting from this surplus torque is used to drive the generator motor 61. In other words, the surplus output is recovered by power generation by the generator motor 61, thereby improving the fuel efficiency of the vehicle.

At timing T2, the absolute value of the difference between the rotational speed NE and the target rotational speed becomes less than the predetermined value ΔNE. Therefore, the EGR rate starts to increase due to the instruction to increase the opening degree of the EGR valve 43, and the surplus torque starts to decrease. Then, at timing T3, the EGR rate becomes constant at a predetermined EGR rate α, and the rotational speed NE, torque, and supercharging pressure become constant.

Next, the main effects of this embodiment will be explained.

The vehicle control method according to the present embodiment is a vehicle control method including an internal combustion engine 1 and a power generation motor 61, in which EGR combustion is performed at a predetermined EGR rate α during steady operation of the internal combustion engine 1, and the internal combustion engine 1, during the transient operation, the EGR rate is lowered than a predetermined EGR rate α, and the excess output of the internal combustion engine 1 generated due to the decrease in the EGR rate is recovered by power generation by the generator motor 61.

According to such a method, since the EGR rate is lowered during transient operation than during steady operation, combustion stability can be maintained without causing misfire, and combustion can be improved. Furthermore, when the EGR rate is lowered, if the throttle opening of the throttle valve 14 is not adjusted accordingly, the torque of the internal combustion engine 1 increases; however, according to this method, the surplus output of the internal combustion engine 1 can be recovered and used through power generation. Therefore, during transient operation, it is possible to improve EGR combustion performed in the internal combustion engine 1 and to improve fuel efficiency.

In the vehicle control method according to the present embodiment, the vehicle is configured as a hybrid vehicle, and the battery is charged with electric power recovered by power generation by the generator motor 61.

According to such a method, battery charging efficiency can be increased by suppressing torque changes due to surplus torque.

In the vehicle control method according to the present embodiment, the EGR rate starts to be lowered below a predetermined EGR rate α before the operation of the internal combustion engine 1 switches from steady operation to transient operation.

According to such a method, it becomes possible to instantaneously generate surplus torque at the timing of switching from steady operation to transient operation.

In the vehicle control method according to the present embodiment, when lowering the EGR rate below a predetermined EGR rate α, the EGR rate is set in a range higher than the EGR rate at which knocking occurs in the internal combustion engine 1.

According to such a method, the operating conditions of the internal combustion engine 1 can be changed without causing knocking.

In the vehicle control method according to the present embodiment, in order to lower the EGR rate below a predetermined EGR rate α, the EGR rate is set in a range lower than the EGR rate corresponding to the combustion stability limit.

According to such a method, combustion stability can be ensured when switching the operating conditions of the internal combustion engine 1.

In the vehicle control method according to the present embodiment, when lowering the EGR rate below a predetermined EGR rate α, the minimum advance angle value that corresponds to the EGR rate and that provides the best torque is satisfied. Set the ignition timing.

According to such a method, thermal efficiency can be increased, and charging efficiency can be increased.

Although the embodiments of the present invention have been described above, the above embodiments merely show a part of the application examples of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above embodiments. do not have.

For example, in the embodiment described above, the case where EGR combustion is performed in the internal combustion engine 1 has been described. However, lean combustion may be performed in the internal combustion engine 1. In this case, the air-fuel ratio can be lowered instead of lowering the EGR rate.

In the embodiment described above, the case where the vehicle is a series hybrid vehicle has been described. However, the vehicle may be a parallel hybrid vehicle that uses at least one of the internal combustion engine 1 and the travel motor as a travel drive source.

In the embodiment described above, a case has been described in which the vehicle control method and control unit are realized by the controller 50. However, the vehicle control method and control unit may be realized by, for example, a plurality of controllers.

1 Internal combustion engine 10 Intake system 20 Exhaust system 30 Supercharger 43 EGR valve 50 Controller (control unit)
61 Generator motor (generator)
62 Motor generator

Claims (6)

A method for controlling a vehicle comprising: an internal combustion engine that is operated by igniting a diluted fuel obtained by diluting fuel gas with a non-fuel gas; and a generator that generates electricity using the driving force of the internal combustion engine.
While the internal combustion engine is operating by the spark ignition, determining whether the operating condition corresponds to a steady operating condition or a transient operating condition,
When the operating condition corresponds to the steady operating condition, the internal combustion engine is operated under a predetermined dilution rate and an ignition timing with a minimum advance value that provides the best torque according to the predetermined dilution rate. death,
When the operating condition corresponds to the transient operating condition, the internal combustion is performed at a dilution rate lower than the predetermined dilution rate and at an ignition timing advanced from the ignition timing under the steady-state operating condition. drive the engine,
Recovering the surplus output of the internal combustion engine generated due to the decrease in the dilution rate through power generation by the generator,
When the operating conditions are switched from the steady operating conditions to the transient operating conditions, reducing the dilution rate prior to advancing the ignition timing;
A vehicle control method characterized by: A method for controlling a vehicle according to claim 1, comprising:
The vehicle is configured as a hybrid vehicle,
charging the battery with the electricity recovered from the power generation by the generator;
A vehicle control method characterized by: A method for controlling a vehicle according to claim 1, comprising:
In lowering the dilution rate below the predetermined dilution rate, setting the dilution rate in a range higher than a dilution rate at which knocking occurs in the internal combustion engine;
A vehicle control method characterized by: A method for controlling a vehicle according to claim 1, comprising:
In lowering the dilution rate below the predetermined dilution rate, setting the dilution rate in a range lower than the dilution rate corresponding to the combustion stability limit;
A vehicle control method characterized by: A method for controlling a vehicle according to any one of claims 1 to 4 ,
the non-fuel gas is EGR gas;
A vehicle control method characterized by: A vehicle comprising an internal combustion engine that is operated by igniting a diluted fuel obtained by diluting fuel gas with a non-fuel gas, and a generator that generates electricity using the driving force of the internal combustion engine, the vehicle comprising:
While the internal combustion engine is operating by the spark ignition, determining whether the operating condition corresponds to a steady operating condition or a transient operating condition,
When the operating condition corresponds to the steady operating condition, the internal combustion engine is operated under a predetermined dilution rate and an ignition timing with a minimum advance value that provides the best torque according to the predetermined dilution rate. death,
When the operating condition corresponds to the transient operating condition, the internal combustion is performed at a dilution rate lower than the predetermined dilution rate and at an ignition timing advanced from the ignition timing under the steady-state operating condition. drive the engine,
Recovering the surplus output of the internal combustion engine generated due to the decrease in the dilution rate through power generation by the generator ,
a control unit that reduces the dilution rate prior to advancing the ignition timing when the operating condition switches from the steady operating condition to the transient operating condition;
A vehicle characterized by having.

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