JP2874449B2 - Operating method of internal combustion engine for power generation of hybrid vehicle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hybrid vehicle equipped with an electric motor for driving a vehicle and an internal combustion engine for power generation, and more particularly to a hybrid vehicle having excellent exhaust gas characteristics while enjoying the advantages of an electric vehicle. The present invention relates to a method for operating an internal combustion engine for power generation of a hybrid vehicle, which can increase the distance and improve the power performance of the vehicle.

[0002]

2. Description of the Related Art In recent years, due to environmental problems, regulations on exhaust gas emitted from vehicles driven by an internal combustion engine have become strict, and many new technologies have been researched and developed in order to respond to this. From the viewpoint of reducing exhaust gas, an electric vehicle that uses an electric motor as a drive source and emits no exhaust gas is ideal. However, a typical electric vehicle supplies power to an electric motor from a battery, and the capacity of the battery that can be mounted on the vehicle is naturally limited. Poor cruising range. In order to spread electric vehicles, it is desired to solve such technical problems.

Accordingly, as a countermeasure for increasing the cruising distance of an electric vehicle, a hybrid electric vehicle which is driven by an internal combustion engine and is equipped with a generator for charging a battery has recently been regarded as promising. Generally, a hybrid vehicle is equipped with an exhaust gas purifying device having, for example, a catalyst for removing harmful substances contained in exhaust gas and a heater for heating the catalyst, in order to improve exhaust gas characteristics of the engine. After heating and activating the catalyst by
The engine operation for charging the battery is started.

[0004]

However, even when the engine is started after the catalyst is activated so that the catalyst functions normally, the fuel is hardly vaporized and the fuel supply amount is corrected to be increased. When the engine is cold, there is a problem that the purification efficiency of the catalyst is reduced due to the deviation of the air-fuel ratio of the air-fuel mixture supplied to the engine from the stoichiometric air-fuel ratio, and the exhaust gas characteristics are deteriorated.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and has an electric motor for driving a vehicle and an internal combustion engine for power generation while enjoying the advantages of an electric vehicle having excellent exhaust gas characteristics. It is an object of the present invention to provide a method of operating an internal combustion engine for power generation of a hybrid vehicle, which can increase the cruising distance and the power performance of the hybrid vehicle.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above objects, the present invention provides an electric motor for driving a vehicle, an internal combustion engine for power generation, and a method for purifying exhaust gas of the internal combustion engine.
An operation method of an internal combustion engine for power generation of a hybrid vehicle having an exhaust gas purifying device including a catalyst means , comprising:
Preheat the catalyst means before starting the gin,
When the internal combustion engine is detected to be
Operation is permitted, and after the internal combustion engine starts, the internal combustion engine warms up.
Until the pneumatic operation is completed, the operation control amount of the internal combustion engine
Is maintained at a predetermined value .

Preferably, the completion of the warm-up operation of the internal combustion engine is determined when a predetermined time has elapsed from the start of the warm-up operation of the internal combustion engine, or when a temperature parameter representing the temperature of the internal combustion engine has reached a predetermined value. Judge .

[0008]

[Function] Exhaust gas purification before starting the internal combustion engine for power generation
The catalytic means of the device is preheated. When the catalyst means is activated by this preheating, the warming-up operation of the internal combustion engine for power generation is started. The engine warm-up operation is controlled by the engine operation
The control is performed in a state where the control amount is maintained at a predetermined value.For example, the control is performed in a state in which the air-fuel ratio of the air-fuel mixture is maintained near the stoichiometric air-fuel ratio at which the exhaust gas purification performance of the catalyst is sufficiently exhibited. In some cases, the exhaust gas characteristics do not deteriorate due to the deviation from the stoichiometric air-fuel ratio. Thereafter, when the warm-up operation of the engine ends, preferably, when a predetermined time has elapsed from the start time of the warm-up operation, or when the engine temperature parameter reaches a predetermined value and the end of the warm-up operation is determined, The operation of the engine for power generation is started, and thereby the battery is charged for improving the power performance of the vehicle and increasing the cruising distance without deteriorating the exhaust gas characteristics. On the other hand, when the battery is not required to be charged, the engine operation is stopped to improve the exhaust gas characteristics.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, a hybrid vehicle (vehicle)
Is equipped with a number of electric motors (one of which is indicated by reference numeral 10) according to its specifications. Electric motor 10
Is used as a drive source of a vehicle, and is composed of a DC motor or an AC motor, and its output shaft is drivingly connected to a drive wheel (not shown) of the vehicle via a power transmission mechanism (not shown) of the vehicle. Have been. The electric motor 10 is electrically connected to the battery 20 via a current control device 50 that operates under the control of the controller 60. When the vehicle travels, the electric motor 10 normally receives power supplied from the battery 20 and operates to operate the vehicle. It is designed to be driven. In addition, the electric motor 10 functions as a generator during deceleration operation of the vehicle, generates deceleration recovery power, and charges the battery 20 with the deceleration recovery power. The electric motor 10 is provided with a motor temperature sensor 11 for detecting the motor temperature. The battery 20 is provided with a battery capacity sensor 21 for detecting a parameter indicating the battery capacity, for example, a battery voltage value.

The hybrid vehicle includes a generator 30 for generating electric power for charging a battery, and an internal combustion engine 40 having an output shaft drivingly connected to a rotating shaft of the generator for driving the generator 30. It has more. The generator 30 is composed of a DC generator or an AC generator, is electrically connected to the battery 20 via the current control device 50, and uses the electric power generated by the generator 30 when the internal combustion engine 40 is operating.
0 is charged. Further, the generator 30 includes a control unit (not shown) for adjusting the amount of power generation and stopping the power generation, and various sensors (not shown) for detecting the generator operation information such as the temperature of the generator and the failure status. Abbreviation). The generator 30 functions as a so-called starter that starts the internal combustion engine 40 by receiving power supply from the battery 20 when the engine is started. However, a starter for starting the engine may be provided separately from the generator 30, and in this case, the generator 30 is dedicated to power generation.

The internal combustion engine 40 for power generation includes, for example, an engine body composed of a small and lightweight piston engine, and various types of fuel supply system, ignition system, fuel injection system, and current control device 50 having a throttle valve. It has an engine drive system (not shown) for controlling start and stop of the engine body, rotation speed control, throttle valve opening degree control and the like including an actuator. An exhaust gas purifier 42 is provided on an exhaust pipe 41 connected to an exhaust port (not shown) of the engine 40 for discharging exhaust gas. The exhaust gas purifying device 42 includes a catalyst for removing harmful substances such as CO and NOx from exhaust gas passing through the exhaust pipe 41, and an electrothermal catalyst heater connected to the battery 20 via the current control device 50. When the catalyst is heated and activated by a heater, it exerts an extremely powerful exhaust gas purifying action. The exhaust gas purification device 42 is provided with a catalyst temperature sensor 43 for detecting a catalyst temperature. Further, the engine 40 is provided with various sensors (not shown) for detecting engine operation information such as the number of revolutions of the engine, the amount of intake air, the throttle valve opening, and the like. Reference numeral 44 denotes a water thermometer for detecting an engine coolant temperature as an engine temperature parameter. Note that an oil thermometer may be used instead of the water thermometer.

As described above, the electric motor 10 and the battery 2
0, a current control device 50 interposed between the generator 30, the internal combustion engine 40, and the catalyst heater of the exhaust gas purification device 42
Under the control of the controller 60, the electrical connection between the corresponding elements is controlled to be switched under the control of the controller 60, and the current value and the conduction direction in the power supply between the corresponding elements are adjusted. Although not shown, the current control device 50 includes, for example, an input unit for inputting a current control device control signal from the controller 60, an electric connection switch transmitted from the input unit, and a current value and current direction adjustment. And an electric power conversion unit responsive to the control output from the adjustment unit.
Further, the current control device 50 is provided with various sensors (not shown) for detecting a temperature, a failure state, and the like of the device.

The controller 60 controls the operation of the electric motor 10, the internal combustion engine 40, and the current control device 50 by inputting various operation information from the various components and various sensors of the hybrid vehicle. Although illustration is omitted, the controller 60 includes, for example, a processor for executing a control program described later, various memories for storing the control program, various data, and the like, a controller 60, the above-described various elements and various sensors, and the like. And various interface circuits for transmitting and receiving signals between the two.

More specifically, the controller 60 includes a motor temperature sensor 11 provided on the electric motor 10, a battery capacity sensor 21 provided on the battery 20, and the exhaust gas purifying device 4.
2 and electrically connected to various sensors provided in the generator 30, the internal combustion engine 40, and the current control device 50, respectively, and also provided in a hybrid vehicle such as a vehicle speed and an accelerator pedal depression amount. It is electrically connected to various sensors (not shown) for detecting vehicle operation information, and from these sensors, a motor temperature signal, a battery capacity signal, a catalyst temperature signal, an engine water temperature signal, a generator operation information (for example, a generator) 30, the internal combustion engine operation information (for example, the rotation speed of the engine 40, the intake air amount, the throttle valve opening), the current control device operation information (for example, the failure condition of the current control device 50), and the vehicle operation information. To be entered. Then, the controller 60, based on the various signals and information thus input,
The generator control signal related to the control of the power generation amount of the generator 30 and the power generation stop, the internal combustion engine control signal related to the control of the start and stop of the internal combustion engine 40, the number of revolutions, etc. A current control device control signal related to control of a current value, a direction of conduction, and the like in power supply between the elements is determined, and the determined control signal is transmitted to the generator 30, the engine 40, and the current control device 50. ing.

The operation of the controller 60 for controlling the operation of the electric motor 10, the internal combustion engine 40, and the exhaust gas purifying device 42 will be described below with reference to FIGS. When the driver turns on the start key to activate the vehicle,
The processor of the controller 60 determines the key-on operation and starts executing the main routine shown in FIG. That is, the processor first executes a key-on action including reading out of the control data backed up at the end of the previous vehicle running from the memory, checking the operating states of the various components of the hybrid vehicle, and the like (step S1). Next, a travel control subroutine shown in detail in FIG. 3 is executed (step S2).

Referring to FIG. 3, in the travel control subroutine, the processor first reads the output of the accelerator pedal depression amount detection sensor to determine the accelerator pedal depression amount θAC.
C is detected (step S21), and then corresponds to a characteristic diagram (FIG. 5) showing the relationship between the accelerator pedal depression amount θACC and the target vehicle speed VT and is described in the control program in advance or stored in the memory of the controller 60 in advance. A target vehicle speed VT suitable for the accelerator pedal depression amount θACC detected in step S21 is obtained according to the calculated target vehicle speed determining arithmetic expression or look-up table (step S22).

As shown in FIG. 5, the target vehicle speed VT is zero in the first depression amount region where the accelerator pedal depression amount .theta.ACC takes a small value from zero to .theta.ACC1 to prevent the vehicle from starting. Depressed amount θACC from θACC1 to θACC2
In the second depressed amount region, which takes a slightly smaller value up to the above, as the depressed amount θACC increases, it increases from zero to VT2 to allow a gentle start of the vehicle, and the accelerator pedal depressed amount θ
In the third depression amount region where ACC exceeds θACC2, the depression amount θACC
Is increased from VT2 at an increase rate greater than the increase rate in the second area as the increase is made, and the normal running of the vehicle is determined.

Referring again to FIG. 3, after determining the target vehicle speed VT, the processor of the controller 60 reads the output of the vehicle speed sensor to detect the actual vehicle speed VV (step S2).
3) Next, the motor power supply amount (required motor drive current value) I
Is calculated (step S24). In the calculation of the motor current I, the processor first calculates a vehicle speed difference (= VV−VT) based on the actual vehicle speed VV detected in step S23 and the target vehicle speed VT determined in step S22. According to the calculation formula or look-up table for determining the required vehicle acceleration corresponding to the characteristic diagram (FIG. 6) representing the relationship between the vehicle speed difference and the required vehicle acceleration, the previously detected actual vehicle speed VV and the previously calculated vehicle speed difference (= VV-VT) is determined.

As shown in FIG. 6, the required vehicle acceleration α is
If the actual vehicle speed VV is greater than the target vehicle speed VT, and thus the vehicle speed difference is positive, the vehicle speed becomes negative, indicating the necessity of decelerating the vehicle, while the vehicle speed difference is negative, indicating the necessity of the acceleration operation. become. The absolute value of the acceleration α increases as the actual vehicle speed increases, even if the absolute value of the vehicle speed difference is constant. After determining the required vehicle acceleration α as described above, the processor calculates the equation PS = [｛CA · (VV) ² + μ · W + α · W /
g｝ · VV] / (K1 · η), the required motor output P
Calculate S. Here, C, A, VV, μ, W, α, and η are the air resistance coefficient, front projected area, actual vehicle speed,
The rolling resistance coefficient, gross weight, required vehicle acceleration, and power transmission efficiency are shown respectively. G and K1 represent the gravitational acceleration and the unit conversion coefficient, respectively.
Set to 0. Note that the above equation is applicable when there is no road gradient. In determining the required motor output,
A lookup table for determining the motor output may be referred to instead of the calculation using the above calculation formula.

Next, the processor calculates the arithmetic expression I = (K2 ·
The required motor drive current value (motor energization amount) I is calculated according to (PS) / (ηMTR · V). Where K2, PS, η
MTR and V represent the unit conversion coefficient, the required motor output, the motor efficiency of the electric motor 10, and the operating voltage of the electric motor 10, respectively, and the coefficient K2 takes, for example, a value of 735. In the next step S25, the processor sends a control signal representing the required motor drive current value I to the current control device 50. In response to the control signal, the current control device 50 performs, for example, duty control such that the motor drive current of the value I is supplied from the battery 20 to the electric motor 10 via the device. As a result, the actual vehicle speed VV increases or decreases to the target vehicle speed VT, or is maintained at the target vehicle speed VT. Therefore,
Immediately after the start key is turned on, if the accelerator pedal depression amount is larger than the value θACC1, the electric motor 10 starts and the vehicle starts.

Referring again to FIG. 2, after the completion of the traveling control subroutine (step S2), the processor of the controller 60 reads the battery capacity signal from the battery capacity sensor 21, and based on this, the amount of charge of the battery 20 is determined. It is determined whether or not the amount is smaller than a predetermined charged amount that allows the vehicle to travel sufficiently by the electric motor 10 (step S).
3). If the result of this determination is negative, that is, if the battery charge is greater than or equal to the predetermined charge and the battery 20 does not need to be charged, the processor issues an internal combustion engine control signal instructing the internal combustion engine 40 to stop. It is sent to the drive system (step S4). As a result, the internal combustion engine 4
If 0 is stopped, the engine is stopped.
If the engine 40 is operating, the operation of the engine is stopped, so that no exhaust gas is generated due to unnecessary operation of the engine.

In the next step S5, it is determined whether or not the start key has been turned off. If the result of this determination is negative, the process returns to the above-described traveling control subroutine (step S2). On the other hand, if it is determined that the start key has been turned off,
The processor performs key-off measures including, for example, writing control data to the backup memory, checking the operating states of the various components of the hybrid vehicle (step S6), and ends the main routine.

When the start key is not turned off and the series of steps S2 to S5 are repeated to supply the required driving current to the electric motor 10 and the vehicle is running, the charged amount of the battery falls below a predetermined charged amount. Therefore, if it is determined in step S3 that the battery needs to be charged, the processor reads the catalyst temperature signal from the catalyst temperature sensor 43, and based on the signal, determines that the catalyst temperature has reached the predetermined temperature required for sufficiently activating the catalyst. Is determined (step S7). If the result of this determination is affirmative and, therefore, there is a risk that exhaust gas containing harmful substances will be emitted from the engine when the internal combustion engine 40 is operated, the processor sends an engine control signal instructing the stop of the engine to the engine drive system. Sending (step S8),
Thereby, the operation stop state of the internal combustion engine 40 is maintained, or the operation of the engine 40 is stopped while the engine is operating. Therefore, if the catalyst temperature decreases for some reason during operation of the engine, the operation of the engine is stopped.

In the next step S9, the processor sends a control signal to the current control device 50 to instruct the catalyst heater of the exhaust gas purifying device 42 to be energized. In response to this control signal, the current control device 50 operates so that a heating current is supplied from the battery 20 to the heater, and as a result, power is supplied to the catalyst heater to heat the catalyst. After the instruction to energize the heater, the processor again determines whether or not a key-off operation has been performed (step S5). If the key-off operation has not been performed, the processor returns to step S2, and returns to the above-described series of steps S2, S3, S7, S8. , S9 and S
Step 5 is repeated.

Thereafter, it is determined in step S7 that the catalyst temperature has reached a predetermined temperature. Accordingly, when the exhaust gas purifying device 42 reaches an operating state in which harmful substances can be removed from exhaust gas by the exhaust gas purifying action of the catalyst, the processor starts the process. A control signal for instructing to stop energization of the heater is sent to the current control device 50 (step S10). As a result, energization of the heater is stopped. The processor then proceeds to FIG.
An engine control subroutine described in detail is executed (step S11).

Referring to FIG. 4, in the engine control subroutine, the processor refers to the contents of the memory of the controller 60 which indicates whether or not an engine control signal for instructing the operation of the engine has been transmitted.
0 is operating (step S11).
1). If the result of this determination is negative, the processor sends a current control device control signal instructing engine start to the current control device 50 (step S112). As a result,
The current control device 50 operates so that a required drive current is supplied from the battery 20 to the starter (generator 30) via the current control device 50, whereby the internal combustion engine 40 is started by the generator 30 as a starter. Is done. As a result, the warm-up operation of the engine 40 is started.

In step S5 of the main routine (FIG. 2) following the engine control subroutine, it is determined again whether or not the start key has been turned off. If the result of this determination is affirmative, the execution of the main routine is terminated after performing the key-off action in step S6. On the other hand, if it is determined in step S5 that the start key has not been turned off, the processing subsequent to the traveling control subroutine (step S2) is executed again as described above.
Here, since the internal combustion engine 40 has already been started in the previous engine control subroutine, a series of steps S
In step S111 of the engine control subroutine (step S11) re-executed after steps S2, S3, S7 and S10, it is determined that the engine is operating.

In this case, the processor of the controller 60 reads the output of the water temperature gauge 44, that is, the engine water temperature signal, and stores a predetermined value of the engine cooling water temperature which is set in advance and indicates the warm-up completion state of the engine 40 in the memory of the controller 60. , And it is determined whether or not the water thermometer output is equal to or more than a predetermined value (step S113). If the result of this determination is negative, that is, if it is determined that the warm-up operation of the engine 40 has not yet been completed, the processor sets the target throttle valve opening θTRG to the first predetermined opening for performing the warm-up operation of the engine 40. Degree θLOW (step S1
14). The first predetermined opening degree θLOW is set to a small value in advance so that the warm-up operation of the engine is performed in an engine operation region where the engine load and the engine speed are small, for example, an idle operation region.

On the other hand, if the result of the determination in step S113 is affirmative, that is, if it is determined that the warm-up operation of the engine has been completed, the target throttle valve opening θTRG is set to the second value for performing the power generation operation of the engine for charging the battery. 2 predetermined opening θ
HIGH is set (step S115). Therefore, when the end of the warm-up operation is determined for the first time, the engine operation for power generation by the generator 30 is started. The second predetermined opening θHIGH is set in advance to a value larger than the first predetermined opening θLOW, whereby the power generation operation of the engine is performed in a state where the load and the rotation speed of the engine are larger than those during the warm-up operation. Done. During the power generation operation, a generator control signal instructing the amount of power generation is supplied from the processor to the generator control unit, and a current control device control signal instructing the battery charging by the generated power is transmitted from the processor to the current control device 50.
Supplied to

Further, the processor detects the current throttle valve opening θTH based on the output of the throttle valve opening sensor, and determines the detected current throttle valve opening θTH in step S
114 or the target throttle valve opening θ set in S115
It is determined whether or not TRG is exceeded (step S116).
If the result of this determination is negative, the processor sends an engine control signal instructing driving of the throttle valve in the opening direction to the engine drive system (step S117). On the other hand, the current throttle valve opening θTH is
If it is determined in step S116 that the value exceeds G, the processor sends an engine control signal instructing the closing direction drive of the throttle valve to the engine drive system (step S116).
118). As a result, the throttle valve of the internal combustion engine 40 is opened or closed by the above-described throttle valve drive mechanism in accordance with the determination result in step S96, and is controlled to the target throttle valve opening θTRG. The engine 40 is operated.

Next, in step S119 following step S117 relating to the throttle valve opening direction driving or step S118 relating to the throttle valve closing direction driving, normal engine control including ignition timing control, fuel injection control and the like is performed. Executed by the processor, thereby
The engine control subroutine ends and returns to the main routine. During the warm-up operation of the engine, the engine 40
The fuel injection control in step S119 is performed so that the air-fuel ratio of the air-fuel mixture supplied to the air-fuel mixture becomes close to the stoichiometric air-fuel ratio.
Exhaust gas purifying performance of the catalyst is sufficiently exhibited, and deterioration of exhaust gas characteristics when the engine is cold is reduced.

Further, step S5 of the main routine is performed.
If it is determined that the start key has not been turned off, the routine returns to the traveling control subroutine (step S2).
On the other hand, if it is determined that the start key has been turned off, the processor executes the above-described key-off processing (step S
6), the main routine ends. To summarize the above-described operation control of the various components of the hybrid vehicle by the controller 60, the calculation of the energization amount to the electric motor 10 and the control of the motor energization amount are started according to the ON operation of the start key. This motor control is performed periodically. As a result, the hybrid vehicle using the electric motor 10 as a drive source runs. If there is no shortage in the charged amount of the battery 20 while the vehicle is running, the operation of the internal combustion engine 40 for driving the generator 30 is stopped, thereby preventing unnecessary emission of exhaust gas. On the other hand, if there is a possibility that the battery charge becomes insufficient, the engine 40 is started and the generator 3
At 0, power is generated, and the battery 20 is charged with the generated power. However, when the engine is started, the catalyst temperature is checked. If the catalyst temperature has not reached the temperature at which the catalyst is activated, the catalyst heater is energized to heat the catalyst. Furthermore,
When the activation of the catalyst is completed, for example, the engine 40 is warmed up in an idling operation state while controlling the fuel supply amount to the engine 40 so that the air-fuel ratio of the air-fuel mixture becomes close to the stoichiometric air-fuel ratio. When the end of the warm-up operation is determined based on the output of the water temperature gauge, the power generation operation of the engine 40 is performed in a state where the load and the rotation speed of the engine are increased. That is, the power generation operation of the engine is started when both the activation of the catalyst and the warm-up operation of the engine are completed, and the battery is charged by this. Since such battery charging is performed every time the vehicle travels, the vehicle can normally travel only from the battery 20 during the period from the start of the vehicle travel to the completion of heating of the catalyst. When the heating of the catalyst is completed, the battery can be charged as required. Therefore,
Normally, traveling of the hybrid vehicle does not become difficult during traveling. Thereafter, when the start key is turned off, the above-described motor control ends, and the vehicle travel by the electric motor 10 is stopped. Further, if the engine is operating at the time of key-off, the above-described engine control is terminated together with the key-off, so that power generation by driving the engine is stopped.

The present invention is not limited to the above embodiment, but can be variously modified. For example, in the embodiment, the termination of the warm-up operation of the engine 40 is determined when the output of the water thermometer reaches a predetermined value. However, an oil thermometer may be used instead of the water thermometer. Further, the elapsed time from the start of the warm-up operation of the engine may be measured, and the end of the warm-up operation may be determined when a predetermined time has elapsed.

[0034]

As described above, the present invention relates to an electric motor for driving a vehicle, an internal combustion engine for power generation, and an internal combustion engine for the internal combustion engine.
An operation of an internal combustion engine for power generation of a hybrid vehicle having an exhaust gas purifying device including a catalyst means for purifying exhaust gas
The catalytic means before starting the internal combustion engine.
Heated and detected that the catalyst means was activated by preheating
The internal combustion engine is allowed to start,
After starting, until the internal combustion engine warm-up operation is completed,
The operation control amount of the internal combustion engine is maintained at a predetermined value.
Exhaust gas characteristics even when the engine is cold.
The engine can be warmed up. In other words , when both the activation of the catalyst and the warm-up operation of the internal combustion engine are finished, the internal combustion engine is started to operate for power generation, so that the exhaust gas characteristics do not deteriorate,
The battery can be charged, thereby improving the power performance of the vehicle and increasing the cruising distance.

Preferably, the completion of the warm-up operation of the internal combustion engine is determined when a predetermined time has elapsed from the start of the warm-up operation of the internal combustion engine or when a temperature parameter representing the temperature of the internal combustion engine has reached a predetermined value. Decided to judge
Therefore, the completion of the warm-up operation can be accurately determined .

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a main part of a hybrid vehicle to which a method for operating an internal combustion engine for power generation according to an embodiment of the present invention is applied.

FIG. 2 is a flowchart showing a main routine of a procedure of operation control of an electric motor for driving a vehicle, an internal combustion engine for power generation, and a catalyst heater, which is executed by the controller shown in FIG.

FIG. 3 is a flowchart showing a detail of a travel control subroutine shown in FIG. 2;

FIG. 4 is a flowchart showing an engine control subroutine shown in FIG. 2 in detail.

FIG. 5 is a characteristic diagram showing a relationship between an accelerator pedal depression amount θACC and a target vehicle speed VT used in a traveling control subroutine.

FIG. 6 shows an actual vehicle speed V used in a travel control subroutine.
FIG. 7 is a characteristic diagram showing a relationship between V, a vehicle speed difference VV-VT, and a vehicle body acceleration α.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Electric motor 11 Motor temperature sensor 20 Battery 21 Battery capacity sensor 30 Generator 40 Internal combustion engine 41 Exhaust pipe 42 Exhaust gas purification device 43 Catalyst temperature sensor 44 Water temperature gauge 50 Current control device 60 Controller VV Actual vehicle speed θACC Accelerator pedal depression amount

Claims (3)

(57) [Claims] An internal combustion engine for power generation of a hybrid vehicle having an electric motor for driving a vehicle, an internal combustion engine for power generation, and an exhaust gas purification device including a catalyst means for purifying exhaust gas of the internal combustion engine. In the operating method of (1), the catalyst means is preheated before the start of the internal combustion engine , and it is detected that the catalyst means has been activated by the preheating.
In this case, the start of the internal combustion engine is permitted , and after the start of the internal combustion engine, the warm-up operation of the internal combustion engine is performed.
The operation control amount of the internal combustion engine is
An operation method of an internal combustion engine for power generation of a hybrid vehicle, wherein the operation is maintained at a constant value . Wherein warming of the internal combustion engine when a predetermined time has elapsed from the start of warm-up of the internal combustion engine
The method for operating an internal combustion engine for power generation of a hybrid vehicle according to claim 1, wherein it is determined that the operation is completed . Wherein warming of the internal combustion engine when the temperature parameter indicative of the temperature of the internal combustion engine reaches a predetermined value
The method for operating an internal combustion engine for power generation of a hybrid vehicle according to claim 1, wherein it is determined that the operation is completed .