JPH102240A - Control device for engine driving generator in hybrid electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve purge process performance of vaporized fuel from a fuel tank without increasing a frequency of driving of an engine, in a hybrid electric vehicle provided with a generator driving engine to run by an electric motor. SOLUTION: After an engine is started, a charge amount SOC of a battery is read (S101), even after leading to a charge completion equivalent value SOCful, driving of the engine is continued, while continuing generation by a rated generation mode (S104), a purge process of vaporized fuel is performed. A correction variable αof a fuel injection amount for air-fuel ratio feedback control is read (S105), based on this variable, a purge condition of vaporized fuel is estimated, by reduction of a purge amount, when the correction variable αcomes to be a purge completion equivalent value αevp or more, by a stop routine (S107), driving of the engine is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control apparatus for a generator driving engine of a hybrid electric vehicle having an electric generator driving engine and running by an electric motor.

[0002]

2. Description of the Related Art An electric vehicle equipped with a generator driving engine is called a series hybrid vehicle (SHEV). This is intended to improve the cruising distance of an electric vehicle by mounting a generator. Generally, when the battery is in a charged state, the vehicle runs on only the energy of the battery, and the amount of charge of the battery is small. When this happens, a system is employed in which the generator drives the engine to charge the battery and stops the engine when the charged amount reaches a predetermined value.

[0003] The SHEV is a low-emission vehicle because the engine drive frequency is less than that of a gasoline engine-driven vehicle. If charging is repeated, the engine will not be driven and exhaust gas will not be exhausted. However, even if the fuel vapor (vapor) from the fuel tank is captured by the canister, it will not be purged into the engine intake system, so it will saturate. It can be released into the atmosphere, which is contrary to the essence of low-emission vehicles.

On the other hand, as a conventional control device for a generator driving engine of a hybrid electric vehicle, there is the following device. (1) JP-A-6-233410 In a hybrid electric vehicle, an engine is driven by a means for detecting the amount of fuel vapor from a fuel tank (measuring the weight of a canister) when the fuel vapor quantity exceeds a predetermined value. Then, the fuel vapor is purged, and the engine is stopped when the fuel pressure drops below a predetermined value.

(2) JP-A-5-270294 In a hybrid electric vehicle, a crank angle sensor of a generator driving engine is monitored, and when the engine is not driven for a predetermined time, the engine is forcibly driven.
Purge evaporated fuel.

[0006]

However, in such a conventional control apparatus for a generator driving engine of a hybrid electric vehicle, only control for driving the engine is performed by measuring or estimating the amount of fuel vapor. Therefore, there is a possibility that the evaporated fuel may not be completely purged when the engine is driven, and there is a problem that the engine is frequently driven when power generation is not necessary depending on the operation method.

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, an object of the present invention is to reduce the frequency of driving the engine by performing control for completely purging evaporated fuel when the engine is driven.

[0008]

According to the first aspect of the present invention, there is provided an electric motor for driving a vehicle, a battery and a generator for supplying electric power, and an electric motor for generating electricity when the charged amount of the battery is equal to or less than a predetermined value. As shown in FIG. 1A, in a hybrid electric vehicle including an engine that drives the engine, a fuel tank for the engine, and an evaporative fuel processing device that purges evaporative fuel generated in the fuel tank into an engine intake system. A purge state estimating means for estimating a purge state of evaporative fuel based on a fuel injection amount correction variable for air-fuel ratio feedback control after the start of driving of the engine; An engine driving continuation unit that continues driving the engine until it is estimated that the fuel purge has been completed is provided, and the generator driving air of the hybrid electric vehicle is provided. Jin constituting the control apparatus.

The invention according to claim 2 is characterized in that, after the charging of the battery is completed, the engine is set to a steady operation, and the estimation by the purge state estimating means is performed. In the invention according to claim 3, as shown by a dotted line in FIG.
After the charging of the battery is completed, a power generation amount reducing means for reducing the power generation amount of the generator to the average required output of the electric motor is provided.

According to a fourth aspect of the present invention, as shown in FIG. 1 (B), in addition to the first aspect of the present invention, a purge completion time predicting means for predicting a purge completion time of the evaporated fuel, and a battery charging completion time Charge completion time prediction means for predicting the time, and power generation amount control means for controlling the power generation amount of the generator based on these prediction results so that the purge of the fuel vapor is completed before the charging of the battery is completed. It is characterized by having.

In the invention according to claim 5, FIG.
As shown in (B), in addition to the invention according to claim 1, purge completion time prediction means for predicting the purge completion time of the evaporated fuel, charge completion time prediction means for predicting the charge completion time of the battery, A purge amount control means for controlling a purge amount based on the prediction result so that the purge of the evaporated fuel is completed before the charging of the battery is completed is provided.

According to a sixth aspect of the present invention, in accordance with the fourth or fifth aspect of the present invention, the engine is assumed to be in a steady operation at a predetermined charge amount or more before the completion of charging of the battery, and the estimation by the purge state estimating means is performed. The prediction by the purge completion time prediction means and the charging completion time prediction means is performed.

[0013]

According to the first aspect of the present invention, after the start of driving of the engine, until the purge of the evaporated fuel is estimated to be completed based on the correction variable of the fuel injection amount for the air-fuel ratio feedback control. By continuing to drive the engine, the fuel vapor can be reliably purged when the engine is running,
In addition, the effect that the driving frequency of the engine does not increase is obtained.

According to the second aspect of the invention, after the charging of the battery is completed, the engine is set to a steady operation and the purge state is estimated, whereby the effect of being able to estimate accurately is obtained. According to the third aspect of the invention, the amount of power generated by the generator is reduced to the average required output of the electric motor after the completion of charging of the battery, so that the amount of charge of the battery can be maintained near the value corresponding to the completion of charging. Thus, the effect of suppressing battery deterioration can be obtained.

According to the fourth aspect of the invention, by controlling the power generation amount of the generator so that the purge of the evaporated fuel is completed before the charging of the battery is completed, the charging amount of the battery is reduced to a value corresponding to the charging completion. And the effect of preventing deterioration of the battery can be obtained. According to the invention according to claim 5, by controlling the purge amount so that the purge of the evaporated fuel is completed before the charging of the battery is completed, the charged amount of the battery does not exceed the charging completion equivalent value, Since the deterioration of the battery can be prevented and the power generation amount is not changed, the effect that the state of the engine can be kept steady can be obtained.

According to the sixth aspect of the present invention, the engine can be operated in a steady state at a predetermined charge amount or more before the completion of charging of the battery, and the purge state is estimated. Can be

[0017]

Embodiments of the present invention will be described below. FIG. 2 shows an example of the SHEV system configuration.
The SHEV receives power from at least one of an engine (internal combustion engine) 10, a generator 11 driven by the engine 10, a battery 12 chargeable by the generator 11, the battery 12, and the generator 11 to drive the vehicle. And an electric motor 13 used for energy regeneration at the time of deceleration, a transmission for transmitting the output of the electric motor 13 to the drive wheels 15, a drive system 14 such as a reduction gear, and a control device 16 for controlling these. Be composed.

When the battery 12 is in a sufficiently charged state (when the energy of the battery 12 satisfies the required output of the motor 13), the motor 13 is driven by the energy of the battery 12,
The generator driving engine 10 does not operate. However, when the charge amount of the battery 12 falls below a predetermined value (when the energy of the battery 12 does not satisfy the required output of the motor 13)
Starts the generator driving engine 10 and uses the energy generated by the generator 11 for supplying energy to the motor 13 and charging the battery 12.

Thereafter, when the charged amount of the battery 12 reaches a predetermined value, the generator driving engine 10 is stopped and the generator 11 is stopped.
To stop power generation. The controller 16 controls input / output of the electric motor 13, charging / discharging of the battery 12, output of the generator 11, starting and stopping of the generator driving engine 10, rotation of the throttle valve, and the like. Is also controlled.

FIG. 3 shows an example of a system configuration of the evaporated fuel processing apparatus. Evaporated fuel (vapor) generated in the fuel tank 20 when the engine is stopped or the like is adsorbed on the canister 22 by the evaporated fuel conduit 21. During the operation of the engine, the evaporated fuel adsorbed by the canister 22 flows together with the air introduced from the atmosphere communication pipe 23 through a purge cut valve 24 and a purge control valve 25 to a purge port 27 provided in an intake pipe 26 of the engine. It is further purged and supplied to the engine together with the intake air.

The purge cut valve 24 is opened when the pressure difference between the front and rear reaches a predetermined value. This pressure difference is a pressure difference between the pressure introduced through a purge VC cut valve 30 from a negative pressure introduction port 29 provided near the throttle valve 28 and the atmospheric pressure. The controller 16 controls the purge control valve 25 and the purge VC cut valve 30, and controls the purge amount of the fuel vapor from the canister 22 and the ON / OFF of the purge.

FIG. 4 shows a flowchart of the first embodiment of the present invention. At the start of the flowchart, the generator 10 is driven by the engine 10 in a state where the charge amount of the battery 12 is equal to or less than a predetermined value. In step 101 (shown in the figure as S101; the same applies hereinafter), the state of charge SOC of the battery 12 is read. Then, in step 102, it is determined whether or not the charge amount SOC has reached the charge completion equivalent value SOCful set in advance as the SOC in the charge completion state.
In the case of SHEV, the value of SOCful is set to about 80% of the full charge value in consideration of energy regeneration and the like.

If the state of charge SOC has not reached SOCful, it is determined that charging has not been completed yet, and
In the normal power generation mode 103, the power generation is continued, and the routine of returning to the charge amount SOC reading step of step 101 is repeated. In the determination at step 102, the state of charge SOC becomes S
When it reaches OCful, it is considered that charging is completed and step
Shift to the rated power generation mode of 104. The rated power generation mode is used to stabilize the state of the generator driving engine 10 (rotational speed and load), stabilize the fluctuation of the intake air amount, and
This is to obtain a constant output from 11.

In step 105, a fuel injection amount correction variable (air-fuel ratio feedback correction coefficient) α for the air-fuel ratio feedback control is read in order to estimate the purge state of the evaporated fuel based on this state. This part corresponds to the purge state estimating means. When a three-way catalyst is used as an exhaust gas purifying device for a gasoline engine, it is necessary for the engine to burn near the stoichiometric air-fuel ratio. The intake air amount is estimated, and a constant (K) adapted to obtain this value and a stoichiometric air-fuel ratio in advance at each rotation speed and load.
Thus, the basic fuel injection amount is determined (basic fuel injection amount Tp = K × Qa / Ne). However, since this alone is not enough to set the air-fuel ratio, the fuel injection amount is feedback-controlled by a signal from an air-fuel ratio sensor (O ₂ sensor) provided in the exhaust system (fuel injection amount Ti = Tp ×
α).

The correction variable (air-fuel ratio feedback correction coefficient) that performs this feedback control is α. α
Is a coefficient of 1 in the state where combustion is performed at the stoichiometric air-fuel ratio, that is, a state in which no correction is performed. However, if it is determined from the signal from the air-fuel ratio sensor that the state is leaner than the stoichiometric air-fuel ratio, the value is increased. If the fuel injection amount is increased, or conversely, if it is determined that the fuel is rich, the value is reduced to decrease the fuel injection amount, thereby repeatedly increasing or decreasing the stoichiometric air-fuel ratio.

Therefore, when the amount of purge of the fuel vapor from the canister 22 is large in the intake air, the purge amount of the fuel vapor becomes excessively large in the normal fuel injection amount. Becomes smaller. Further, when the purge amount is reduced, the amount becomes leaner, so that the value of α increases in order to increase the fuel injection amount. This gives α
By monitoring the value of, it is possible to estimate the purge amount of the evaporated fuel into the intake air.

In step 106, it is determined whether or not the air-fuel ratio feedback correction coefficient α has become equal to or greater than a preset purge completion equivalent value αevp. When the air-fuel ratio feedback correction coefficient α is smaller than αevp, it can be determined that the amount of fuel in the intake air is large, that is, it is determined that the purge of the evaporated fuel has not been completed.
Continue purging. This portion corresponds to engine drive continuation means.

The air-fuel ratio feedback correction coefficient α is αevp
When this is the case, it is determined that the purge of the fuel vapor has been completed, and the routine proceeds to the stop routine of step 107, where the generator driving engine 10 is stopped. The purge completion equivalent value α
Since evp is set on the rich side of the stoichiometric air-fuel ratio, it is a value smaller than the coefficient 1. Also, in order to avoid malfunctions such as the engine not stopping forever, fluctuation of the α value without purging of evaporated fuel A predetermined value is set for each system in consideration of the width.

FIG. 5 is a time conceptual diagram of the first embodiment. The horizontal axis in the figure is time, the vertical axis in the upper figure is the battery charge SOC, and the vertical axis in the lower figure is the air-fuel ratio feedback correction coefficient α. In this figure, since the air-fuel ratio feedback correction coefficient α has not reached the purge completion equivalent value αevp even at the time Ta1 when the charge amount SOC has reached the charge completion equivalent value SOCful, the air-fuel ratio feedback correction coefficient α becomes the purge completion equivalent value. This shows a situation in which the driving of the engine is extended and the purging is completely performed until the time Ta2 when αevp is reached.

The first embodiment has the advantage that the control is very simple and the program is easy. FIG. 6 shows a flowchart of the second embodiment of the present invention. As in the first embodiment, when the charge amount of the battery 12 is equal to or less than the predetermined value,
A generator 11 is driven by 10.

In step 201, the state of charge SOC of the battery 12
It is determined whether or not the charge amount SOC has reached a preset charge completion equivalent value SOCful in step 202. If the charge amount SOC has not reached SOCful, power generation is performed in the normal power generation mode in step 203. continue. When the state of charge SOC has reached SOCful, it is considered that charging has been completed, and the process proceeds to step 204 in the rated power generation mode.

Next, in step 205, a correction variable (air-fuel ratio feedback correction coefficient) α of the fuel injection amount for the air-fuel ratio feedback control is read, and in step 206, the air-fuel ratio feedback correction coefficient α is set to a preset purge completion equivalent value αevp. It is determined whether or not the above has been achieved. This part corresponds to the purge state estimating means. When the air-fuel ratio feedback correction coefficient α is smaller than αevp, it can be determined that the purging of the evaporated fuel has not been completed, so that the generator driving engine 10 is continuously driven and the purging is continued. This portion corresponds to engine drive continuation means.

At this time, in step 207, the average required output Wmot of the electric motor 13 within a predetermined time from the present time is calculated, and in step 208, the required power generation amount Wgen is calculated from the required output Wmot in consideration of the efficiency of each part. The engine speed Ne is determined based on the required power generation amount Wgen according to the map, the generator 11 and the engine 10 for driving the generator are set to the values obtained in steps 208 and 209 in step 210, and then the α reading step in step 205 is performed. Repeat the return routine.

Thus, after charging of the battery 12 is completed,
Since only the average required output of the electric motor 13 is generated, it is possible to maintain the charge amount SOC of the battery 12 near the charge completion equivalent value SOCful while purging the fuel vapor.
If it is determined in step 206 that the air-fuel ratio feedback correction coefficient α is equal to or larger than αevp, it is determined that the purge of the evaporated fuel has been completed, and the process proceeds to the stop routine of step 211 to stop the generator driving engine 10. Stop.

FIG. 7 is a time conceptual diagram of the second embodiment. The horizontal axis in the figure is time, the vertical axis in the upper figure is the battery charge SOC, and the vertical axis in the lower figure is the air-fuel ratio feedback correction coefficient α. In this figure, charging is completed at time Tb1, but since the air-fuel ratio feedback correction coefficient α at this time has not yet reached the purge completion equivalent value αevp, driving of the engine is continued. However, if the power generation amount is kept as it is, the charge amount SOC continues to increase. Therefore, the output is reduced to the average required output of the electric motor so that the charge amount SOC does not seem to increase or decrease. Accordingly, the purge amount of the evaporated fuel in the engine is reduced by the decrease in the power generation amount, so that the change in the air-fuel ratio feedback correction coefficient α becomes gentle after Tb1.

The second embodiment has the advantage that the amount of power generation is reduced after the completion of charging of the battery, so that the state of charge of the battery can be maintained near SOCful, and the deterioration of the battery can be suppressed. 8 and 9 show a flowchart of the third embodiment of the present invention. At the start of the flowchart, as in the first embodiment, the generator 10 is driven by the engine 10 in a state where the charge amount of the battery 12 is equal to or less than a predetermined value.

In step 301, the charge amount S of the battery 12
Read OC. Then, in step 302, the charge amount SO
It is determined whether or not C has reached a preset purge amount determination charge value SOCevp. Purge amount judgment charge value SOCevp
Is a value smaller than the charging completion equivalent value SOCful, and is a value determined from the charging capacity, the exhaust from the engine, the evaporative fuel capture capacity of the canister, the purging capacity of the purge system, etc., and the amount of evaporative fuel between SOCevp and SOCful. Make sure that the purge is completed without affecting other performance (exhaust from the engine, motor driving power, charging the battery, etc.)
This is a value set by experiments or the like for each system.

If the state of charge SOC has not reached SOCevp, in the normal power generation mode of step 303, the power generation is continued, and the routine of returning to step 301 for reading the state of charge SOC is repeated. In the determination at step 302,
If the state of charge SOC has reached SOCevp, step 30
Shift to the rated power generation mode of 4.

Next, in step 305, a correction variable (air-fuel ratio feedback correction coefficient) α of the fuel injection amount for the air-fuel ratio feedback control is read, and in step 306, the air-fuel ratio feedback correction coefficient α is set to a preset purge completion equivalent value αevp It is determined whether or not the above has been achieved. This part corresponds to the purge state estimating means. When the air-fuel ratio feedback correction coefficient α is smaller than αevp, it can be determined that the purging of the evaporated fuel has not been completed, so that the generator driving engine 10 is continuously driven and the purging is continued. This portion corresponds to engine drive continuation means.

At this time, in step 307 (FIG. 9), the remaining purge amount is calculated by replacing it with the α value, and αres = αevp−α
And Then, in step 308, an increase rate of α (a decrease rate of the purge amount) Δα = α _n −α _n-1 is obtained, and in step 309
Then, from the remaining purge amount αres and the α increase rate Δα, the time until the completion of the purge when the current purge state is maintained (purge completion time) tα = αres / Δα is calculated. This part corresponds to the purge completion time estimating means.

In step 310, the current state of charge SOC
Is read, and in step 311 the remaining charge amount S until the charging is completed
OCres = SOCful-SOC is determined. Then, at step 312, the SOC increase rate ΔSOC = SOC _n −SOC
_In step 313, the time until the completion of the charging when the current state of charge is maintained (charging completion time) tsoc is calculated from the remaining charge amount SOCres and the SOC increase rate ΔSOC at step 313.
Calculate SOCres / ΔSOC. This part corresponds to the charging completion time prediction means.

In step 314, the purge completion time tα is compared with the charge completion time tsoc, and tα ≦ tsoc (the purge of the fuel vapor is completed before the battery is completely charged).
It is determined whether or not. In the case of tα ≦ tsoc, the purge is completed before the charging is completed even in the current state, so that the routine returning to the α reading step of step 305 (FIG. 8) is repeated without performing any special processing.

However, in the case of tα> tsoc, the charging is completed first before the purging is completed under the current condition, and it is expected that the battery will eventually be overcharged.
At step 315, the power generation amount (= charge amount) Wgen is reduced by the power generation amount reduction set value Wred (Wgen = Wgen−Wred).
), And thereafter, the routine of returning to the α reading step of step 305 (FIG. 8) is repeated. This part corresponds to a power generation amount control unit that controls the power generation amount of the generator 11 so that the purge of the evaporated fuel is completed before the charging of the battery is completed.

This routine is repeated, and when the air-fuel ratio feedback correction coefficient α becomes equal to or greater than the purge completion equivalent value αevp in the determination at step 306, it is determined that the purge of the evaporated fuel has been completed, and the routine proceeds to step 316. . In step 316, the current state of charge SOC is changed to a value corresponding to the charge completion SOC.
It is determined whether or not the state of charge is greater than or equal to ful. If the state is less than SOCful, the process proceeds to the step of reading the charge amount SOC in step 317, and the routine of steps 316 and 317 is repeated to maintain the current state of charge. Then, when it becomes equal to or more than SOCful, it is considered that the charging is completed, and the process proceeds to the stop routine of step 318 to stop the generator driving engine 10.

According to this flow, the purge of the evaporated fuel can be surely completed without exceeding the charge amount. FIG. 10 is a temporal conceptual diagram of the third embodiment. The horizontal axis in the figure is time, and the vertical axis in the upper figure is the battery charge amount SO.
C, the vertical axis in the figure below is the air-fuel ratio feedback correction coefficient α.

In this figure, at the time Tc1 when the state of charge SOC reaches SOCevp, as a result of estimating the charge completion time Tc2 and the purge completion time Tc3, the purge completion time Tc3 is temporally later than the charge completion time Tc2. (Dotted line). Therefore, the power generation amount (= charge amount) is set so that the completion of the charging is delayed and the purge of the fuel vapor is completed by then.
Is decreasing.

In the third embodiment, since the amount of power generation (charging amount) is controlled before the battery charging is completed, the battery charging amount does not exceed SOCful, and the battery can be prevented from being deteriorated. There is. FIGS. 11 and 12 show a flowchart of the fourth embodiment of the present invention. At the start of the flowchart, as in the first embodiment, the generator 10 is driven by the engine 10 in a state where the charge amount of the battery 12 is equal to or less than a predetermined value.

In steps 401 to 414,
Steps 301 to 314 of the third embodiment (FIGS. 8 and 9) are the same as those of the third embodiment and will be described hereinafter. Steps
At 414 (FIG. 12), the purge completion time tα and the charge completion time tso
As a result of comparison with c, when tα ≦ tsoc, the purge of the evaporated fuel is completed before the battery charging is completed even in the current state.
The routine of returning to the α reading step of FIG. 8 is repeated.

However, in the case of tα> tsoc, it is expected that charging will be completed first before purging is completed under the current condition, and eventually an overcharged state will result.
The flow shifts to the purge amount increasing mode of step 415. In the barge amount increasing mode, first, at step 416, the charging completion time t
The required purge amount for completing the purge of the fuel vapor within the soc is calculated. Specifically, the required α per unit time
The required amount of purge is determined from the reduced amount of the value.
Next, in step 417, the required purge amount is converted into the opening of the purge control valve (PCV) 25, and in step 418
Sends an opening command to the purge control valve (PCV) 25 to increase the purge amount. Thereafter, the routine of returning to the α reading step of step 405 (FIG. 11) is repeated. This part corresponds to a purge amount control unit that controls the purge amount so that the purge of the evaporated fuel is completed before the charging of the battery is completed.

Note that the opening command for the purge control valve 25 in step 418 may change from the stoichiometric air-fuel ratio if the opening is suddenly changed. And set it as follows. If the purge amount is increased, the α value greatly deviates from the base (coefficient 1), and it is difficult to control the stoichiometric air-fuel ratio when the engine has a transient operation.
In the case of EV, since the engine can be operated in a steady state, the purge amount can be increased while controlling the stoichiometric air-fuel ratio.

This routine is repeated, and when the air-fuel ratio feedback correction coefficient α is equal to or greater than the purge completion equivalent value αevp in the determination at step 406, it is determined that the purge of the evaporated fuel has been completed, and the routine proceeds to step 419. . In step 419, the current state of charge SOC is set to a value corresponding to the completion of charging SOC.
It is determined whether or not the state of charge is greater than ful. If the state is less than SOCful, the process proceeds to the step of reading the state of charge SOC in step 420, and the current state of charge is maintained by repeating the routine of steps 419 and 420. Then, when it becomes equal to or more than SOCful, it is considered that charging is completed, and the process proceeds to a stop routine of step 421 to stop the generator driving engine 10.

According to this flow, the purge of the evaporated fuel can be surely completed without controlling the power generation amount and without exceeding the charge amount. FIG. 13 is a temporal conceptual diagram of the fourth embodiment. The horizontal axis in the figure is time, the vertical axis in the upper figure is the battery charge SOC, and the vertical axis in the lower figure is the air-fuel ratio feedback correction coefficient α.

In this figure, at the time Td1 when the charge amount SOC reaches SOCevp, the charge completion time Td2 is estimated, and it is presumed that the α value at the time Td2 does not reach αevp. For this reason, the purge amount is increased so that the purge of the evaporated fuel is completed by Td2. Thus, the purge of the evaporated fuel is completed within the normal charging completion time without changing the charging characteristics.

In the fourth embodiment, the amount of purge is controlled before the completion of charging of the battery, so that the amount of charge of the battery does not exceed SOCful, and there is an advantage that deterioration of the battery can be prevented. In addition, since the amount of power generation is not changed, the state of the engine can be maintained at a steady state, and there is an advantage that exhaust gas purification is more effective.

[Brief description of the drawings]

FIG. 1 is a functional block diagram showing a configuration of the present invention.

FIG. 2 is a SHEV system configuration diagram showing an embodiment;

FIG. 3 is a system configuration diagram of an evaporative fuel treatment apparatus showing an embodiment.

FIG. 4 is a flowchart of a first embodiment.

FIG. 5 is a temporal conceptual diagram of the first embodiment.

FIG. 6 is a flowchart of a second embodiment.

FIG. 7 is a temporal conceptual diagram of the second embodiment.

FIG. 8 is a flowchart (part 1) of a third embodiment.

FIG. 9 is a flowchart (part 2) of the third embodiment.

FIG. 10 is a conceptual diagram of time according to the third embodiment.

FIG. 11 is a flowchart (part 1) of a fourth embodiment.

FIG. 12 is a flowchart (part 2) of the fourth embodiment.

FIG. 13 is a conceptual conceptual diagram of the fourth embodiment in terms of time.

[Explanation of symbols]

 10 Engine 11 Generator 12 Battery 13 Electric motor 14 Drive system 15 Drive wheels 16 Control device 20 Fuel tank 22 Canister 25 Purge control valve 26 Engine intake pipe

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location F02D 41/02 301 F02M 25/08 301U F02M 25/08 301 B60K 9/00 Z (72) Inventor Hiroyuki Hirano 2 Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Prefecture Nissan Motor Co., Ltd. 2 Takara-cho, Nissan Motor Co., Ltd.

Claims (6)

[Claims] An electric motor for driving a vehicle, a battery and a generator for supplying electric power, an engine for driving the generator with a charged amount of the battery being equal to or less than a predetermined value, a fuel tank for the engine, A fuel-evaporation processing device for purging evaporative fuel generated in a tank to an engine intake system, a hybrid electric vehicle including, after driving of the engine, based on a correction variable of a fuel injection amount for air-fuel ratio feedback control, Purge state estimating means for estimating a purge state of evaporative fuel; and engine drive continuation means for continuing driving of the engine after the start of driving the engine until the estimating means estimates that purging of evaporative fuel is completed. A control device for an engine for driving a generator of a hybrid electric vehicle. 2. The control device for an engine for driving a generator of a hybrid electric vehicle according to claim 1, wherein after the charging of the battery is completed, the engine is set to a steady operation and the estimation by the purge state estimating means is performed. 3. The hybrid electric vehicle according to claim 1, further comprising a power generation amount reducing means for reducing the power generation amount of the generator to an average required output of the electric motor after the completion of charging of the battery. Control system for generator driving engine. 4. A purging completion time estimating means for estimating a purging completion time of evaporative fuel, a charging completion time estimating means for estimating a charging completion time of a battery, and a charging completion time estimating means based on these prediction results. 2. A control device for an engine for driving a generator of a hybrid electric vehicle according to claim 1, further comprising power generation amount control means for controlling the power generation amount of the generator so that the purge of the evaporated fuel is completed. 5. A purge completion time estimating means for estimating a purge completion time of evaporative fuel, a charge completion time estimating means for estimating a charge completion time of a battery, and a charging completion time before completion of battery charging based on these prediction results. 2. The control device according to claim 1, further comprising a purge amount control means for controlling a purge amount such that the purge of the evaporated fuel is completed. 6. The method according to claim 1, wherein the engine is set to a steady operation at a predetermined charge amount before the completion of charging of the battery, and the estimation by the purge state estimating means, and the prediction by the purge completion time estimating means and the charging completion time estimating means are performed. The control device for an engine for driving a generator of a hybrid electric vehicle according to claim 4 or claim 5.