JP6798596B2 - Vehicle drive control - Google Patents

Description

The present invention relates to a vehicle drive control device, and more particularly to a vehicle drive control device capable of increasing the accuracy of oxygen sensor failure diagnosis or catalyst deterioration diagnosis.

Conventionally, vehicles such as hybrid vehicles are equipped with an engine and a motor generator (power generation motive) as power sources, and a front oxygen sensor that detects the oxygen concentration in the exhaust gas on the upstream side of the catalyst that purifies the exhaust gas of the engine. And some are equipped with a drive control device equipped with a rear oxygen sensor that detects the oxygen concentration in the exhaust gas on the downstream side of the catalyst.
In such a drive control device, the oxygen sensor failure diagnosis of the front oxygen sensor and the rear oxygen sensor or the catalyst deterioration diagnosis of the catalyst is executed.
As the catalyst deterioration diagnosis control device, for example, there are the following prior art documents.

Japanese Unexamined Patent Publication No. 2014-134164

The catalyst deterioration determination control device according to JP-A-2014-134164 includes a front oxygen sensor and a rear oxygen sensor, and the output value of the rear oxygen sensor is before execution of forced air-fuel ratio control for forcibly changing the air-fuel ratio. In addition, when the value changes beyond a preset value, the execution of forced air-fuel ratio control is prohibited, and the normality or deterioration of the catalyst is diagnosed based on the reaction time of the rear oxygen sensor. ..

By the way, in order to execute the oxygen sensor failure diagnosis or the catalyst deterioration diagnosis, it is necessary to perform the engine in a stable state.
However, in a hybrid vehicle, the engine torque is increased by executing the operating point correction control for shifting and correcting the current operating point of the engine so as to approach a preset operating point with a good fuel consumption rate. The engine condition fluctuates and the engine condition is not stable. Therefore, the oxygen sensor failure diagnosis or the catalyst deterioration diagnosis is interrupted, and it takes a long time to complete the oxygen sensor failure diagnosis or the catalyst deterioration diagnosis, resulting in an oxygen sensor failure. There is a disadvantage that the accuracy of the diagnosis or the catalyst deterioration diagnosis is lowered.

Therefore, an object of the present invention is to provide a vehicle drive control device capable of increasing the accuracy of oxygen sensor failure diagnosis or catalyst deterioration diagnosis.

According to the present invention, in a vehicle drive control device including an engine and a motor generator and an oxygen sensor for detecting an oxygen concentration in the exhaust gas of the engine, the oxygen sensor failure diagnosis of the oxygen sensor and a preset fuel consumption rate The operating point correction control that corrects the target engine torque and the target motor torque based on a predetermined correction amount is executed so that the current operating point of the engine matches the good operating point of the engine. When the oxygen sensor failure diagnosis is being executed, the predetermined operating point of the engine is set to a constant amount smaller than the correction amount when the operating point is corrected to a preset operating point with a good fuel consumption rate. The purpose is to limit the amount of correction.

The present invention limits changes in engine torque due to operating point correction control so as to reduce fluctuations in engine torque when oxygen sensor failure diagnosis is being performed or catalyst deterioration diagnosis is being performed, and oxygen sensor failure diagnosis or catalyst The deterioration diagnosis can be completed at an early stage, and the accuracy of the oxygen sensor failure diagnosis or the catalyst deterioration diagnosis can be improved.

FIG. 1 is a system configuration diagram of a vehicle drive control device. (Example 1) FIG. 2 is a block diagram showing a flow of operating point correction control when the operating point correction limit is executed. (Example 1) FIG. 3 is a flowchart of operating point correction limit control. (Example 1) FIG. 4 is a graph of operating point correction limit control. (Example 1) FIG. 5 is a graph of operating point correction control and operating point correction limit control in the case of engine torque increase correction. (Example 1) FIG. 6 is a graph of operating point correction control and operating point correction limit control in the case of reduction correction of engine torque. (Example 1) FIG. 7 is a flowchart of stopping the operating point correction control. (Example 2) FIG. 8 is a block diagram showing a flow of operating point correction control when torque change reduction is executed. (Example 3) FIG. 9 is a flowchart of torque change reduction control. (Example 3)

The object of the present invention is to improve the accuracy of the oxygen sensor failure diagnosis or the catalyst deterioration diagnosis, so that the fluctuation of the engine torque is reduced when the oxygen sensor failure diagnosis is being executed or the catalyst deterioration diagnosis is being executed. The change in engine torque due to correction control is limited, and the diagnosis of oxygen sensor failure diagnosis or catalyst deterioration diagnosis is completed and realized at an early stage.

1 to 6 show Example 1 of the present invention.
As shown in FIG. 1, the hybrid vehicle (hereinafter referred to as "vehicle") 1 is provided with an engine 2 and a motor generator (power generation motive) 3 as power sources.
The engine 2 burns fuel to generate power. The motor generator 3 generates electric power by the power of the engine 2 or the rotational drive from the drive wheels when the vehicle decelerates, and is supplied from a high-voltage battery (hereinafter, simply referred to as “battery”) 5 provided in the vehicle 1. The drive torque is generated by electric power. A transmission 4 that transmits the power of the engine 2 to the drive wheels is connected to the engine 2. The battery 5 is composed of a rechargeable secondary battery.
Further, the vehicle 1 is provided with a drive control device 6 for the vehicle 1.
An exhaust passage 8 formed by an exhaust pipe 7 is connected to the engine 2. A catalyst 9 for purifying the exhaust gas of the engine 2 is arranged in the middle of the exhaust passage 8.
Further, the engine 2 includes an injector (fuel injection valve) 10 that injects fuel into the combustion chamber, a spark plug 11 that ignites the fuel injected into the combustion chamber, and a throttle valve that adjusts the amount of intake air into the combustion chamber. 12 and are provided.

The injector 10, the spark plug 11, and the throttle valve 12 are connected to the output side of the engine control means (ECM: EngineControlModule) 13 and are controlled by the engine control means 13. That is, the engine control means 13 outputs a fuel injection amount / fuel injection request signal to the injector 10, an ignition request signal to the spark plug 11, and further, a throttle opening request signal for the intake air to the throttle valve 12. Is output.
The transmission 4 is connected to a transmission control means (TCM: Transmission Control Module) 14 and is controlled by the transmission control means 14. The transmission control means 14 outputs a shift status signal to the transmission 4.
The motor generator 3 is connected to a hybrid control means (HCU: HybridControlModule) 16 via an inverter 15 and is controlled by the hybrid control means 16. That is, when the hybrid control means 16 outputs the motor drive request signal to the inverter 15, the inverter 15 outputs the motor voltage adjustment signal to the motor generator 3, and the motor generator 3 is controlled.
The hybrid control means 16 is connected to the battery 5 and the engine control means 13, monitors a battery state information signal including information such as the charge state of the battery 5 and the cell temperature, and outputs the signal to the engine control means 13.

The exhaust passage 8 of the engine 2 includes a front oxygen sensor 17 that detects the oxygen concentration in the exhaust gas in the exhaust gas 8 on the upstream side of the catalyst 9, and an oxygen concentration in the exhaust gas in the exhaust gas 8 on the downstream side of the catalyst 9. A rear oxygen sensor 18 for detecting the above is provided. It is also possible to use an air-fuel ratio (A / F) sensor instead of the front oxygen sensor 17.
The front oxygen sensor 17 and the rear oxygen sensor 18 are connected to the input side of the engine control means 13. The front oxygen sensor 17 outputs the pre-catalyst oxygen concentration signal as an output value to the engine control means 13. The rear oxygen sensor 18 outputs a post-catalyst oxygen concentration signal as an output value to the engine control means 13.

A transmission control means 14 is connected to the engine control means 13 on the input side. The transmission control means 14 outputs a shift status signal of the transmission 4 and a torque request signal of the transmission 4 to the engine control means 13.
Further, the engine control means 13 has a wheel speed sensor 19 that detects the rotational speed state of the wheels and outputs a wheel speed information signal on the input side, and a vehicle speed information signal that detects the vehicle speed that is the speed of the vehicle 1. The vehicle speed sensor 20 that outputs, the accelerator pedal sensor 21 that detects the depression state of the accelerator pedal and outputs the accelerator pedal depression amount signal, and the engine rotation speed information that detects the rotation speed of the crank shaft of the engine 2 as the engine rotation speed. The crank sensor 22 that outputs a signal and the vehicle running state sensor 23 that detects the running state of the vehicle 1 and outputs the torque request signal of the vehicle 1 are connected.
As the vehicle running state sensor 23, for example, an anti-lock braking system (ABS) or an electronic stability control (ESP) can be used. The anti-lock braking system reduces the occurrence of gliding due to wheel locking, and outputs a torque request signal in order to further stabilize the vehicle behavior. The electronic stability control device stabilizes the posture of the vehicle 1 when turning, and outputs a torque request signal in order to further stabilize the vehicle behavior.

The engine control means 13 is provided with so-called fuel cut control in which the supply of fuel to the engine 2 is stopped (cut) in order to reduce the fuel consumption rate when a predetermined condition is satisfied when the vehicle 1 is decelerated. A fuel cut control unit 24 for executing is provided.

FIG. 2 shows a block diagram showing a flow of operating point correction control of the engine 2 when the operating point correction limitation is executed in the first embodiment.
As shown in FIG. 2, the engine control means 13 includes an oxygen sensor failure diagnosis unit 25 that executes an oxygen sensor failure diagnosis of the front oxygen sensor 17 and the rear oxygen sensor 18, and a catalyst deterioration that executes a catalyst deterioration diagnosis of the catalyst 9. A determination unit 26 and a best operating point setting unit 27 in which an operating point having a good fuel consumption rate of the engine 2 is set in advance are provided.
Here, the operating point correction control means, for example, correcting the target engine torque and the target motor torque so as to shift the current operating point of the engine 2 to the preset operating point having the best fuel consumption rate. Is.
Further, the oxygen sensor failure diagnosis is, for example, a predetermined operation in which the output value of the front oxygen sensor 17 or the rear oxygen sensor 18 is equal to or more than the specified value or less than the specified value, or the front oxygen sensor 17 detects a rich state of the air fuel ratio. Under the conditions, when the rear oxygen sensor 18 detects the lean state of the air fuel ratio for the specified time, or when the fuel cut control of the engine 2 is performed, the output value of the front oxygen sensor 17 or the rear oxygen sensor 18 is the air fuel ratio for the specified time. When the rich state is detected, the failure of the front oxygen sensor 17 or the rear oxygen sensor 18 is diagnosed.
Further, the catalyst deterioration diagnosis is to determine the deterioration of the catalyst 9 from the difference between the output value of the front oxygen sensor 17 and the output value of the rear oxygen sensor 18. For example, the deterioration of the catalyst 9 can be determined based on the area difference (time and output value) calculated from the output value of the front oxygen sensor 17 and the output value of the rear oxygen sensor 18, or the engine 2 has a stoichiometric air-fuel ratio. The time from lean to reversal of the output value of the rear oxygen sensor 18 when forcibly shifting from the operating state of the engine to the clear rich state, and the clear lean state of the engine 2 from the operating state at the stoichiometric air-fuel ratio. The deterioration of the catalyst 9 is determined by measuring the time from the rich to the reversal of the output value of the rear oxygen sensor 18 at the time of forcibly shifting to the lean.

As shown in FIG. 2, the engine control means 13 includes a target torque calculation unit 28, an operating point calculation unit 29, an operating point correction amount calculation unit 30, and an operating point correction limit as the operating point correction amount adjusting unit 31. A unit 32, an operating point correction execution unit 33, an engine output control unit 34, and a motor output request unit 35 are provided.
The target torque calculation unit 28 calculates the required torque to the vehicle 1 from at least the amount of depression of the accelerator pedal detected by the accelerator pedal sensor 21, and calculates the target engine torque and the target motor torque from the calculated required torque.
Specifically, the target torque calculation unit 28 includes a vehicle speed signal detected by the vehicle speed sensor 20, a signal of the accelerator pedal depression amount detected by the accelerator pedal sensor 21, and battery information from the hybrid control means 16. A state signal, a torque request signal of the transmission 4 from the transmission control means 14, and a torque request signal of the vehicle 1 as the vehicle running state detected by the vehicle running state sensor 23 are input, and a map ( The target engine torque and the target motor torque are calculated according to (not shown). Then, the target torque calculation unit 28 outputs the calculated target engine torque signal to the operating point calculation unit 29 and the operating point correction execution unit 33. Further, the target torque calculation unit 28 outputs the calculated target motor torque signal to the operating point correction execution unit 33.
The operating point calculation unit 29 inputs the signal of the target engine torque from the target torque calculation unit 28 and the signal of the engine rotation speed detected by the crank sensor 22, and calculates the current operating point of the engine 2. Then, the operating point calculation unit 29 outputs the calculated operating point signal of the engine 2 to the correction amount calculation unit 30.
The operating point correction amount calculation unit 30 is preset with the operating point signal of the engine 2 from the operating point calculation unit 29, the engine rotation speed signal detected by the crank sensor 22, and the best operating point setting unit 27. The signal of the operating point with a good fuel consumption rate is input, and the engine torque correction amount and the motor torque correction amount are calculated. Then, the operating point correction amount calculation unit 30 outputs the calculated engine torque correction amount signal and the motor torque correction amount signal to the operating point correction limiting unit 32.

The operating point correction limiting unit 32 includes an engine torque correction amount signal and a motor torque correction amount signal from the operating point correction amount calculation unit 30, an oxygen sensor failure diagnosis state signal from the oxygen sensor failure diagnosis unit 25, and a catalyst. The signal of the catalyst deterioration diagnosis state from the deterioration determination unit 26 is input, and the limited engine torque correction amount and motor torque correction amount are obtained. Then, the operating point correction limiting unit 32 outputs the limited engine torque correction amount signal and the motor torque correction amount signal to the operating point correction executing unit 33.
The operating point correction limiting unit 32 controls the operating point correction of the operating point correction executing unit 33 at least when the oxygen sensor failure diagnosis of the front oxygen sensor 17 and the rear oxygen sensor 18 is being executed or the catalyst deterioration diagnosis of the catalyst 9 is being executed. The predetermined correction amount (described later) is limited. This is to limit the change in the engine torque due to the operating point correction control so as to reduce the fluctuation in the engine torque when the oxygen sensor failure diagnosis or the catalyst deterioration diagnosis is being performed.
Here, the limitation of the change in the engine torque by the operating point correction control is, for example, that the change in the engine torque is reduced by gradually performing the correction (the correction amount is gradually increased), and the operating point of the engine 2 is set. It corrects to the target operating point.
Specifically, the operating point correction limiting unit 32 limits the operating point correction amount when at least the oxygen sensor failure diagnosis of the front oxygen sensor 17 and the rear oxygen sensor 18 is being executed or the catalyst deterioration diagnosis of the catalyst 9 is being executed. The operating point correction execution unit 33 determines the engine torque correction amount for correcting the target engine torque of the operating point correction control of the operating point correction execution unit 33 and the motor torque correction amount for correcting the target motor torque. The operating point correction limit control that limits the amount of correction by increasing or decreasing at a predetermined rate is executed. This is to correct the current operating point of the engine 2 so that it gradually approaches the target operating point, and when the oxygen sensor failure diagnosis is being executed or the catalyst deterioration diagnosis is being executed, a large change in engine torque is performed. This is to prevent the occurrence of.

Further, the operating point correction limiting unit 32 limits the operating point correction position by at least performing the oxygen sensor failure diagnosis of the front oxygen sensor 17 and the rear oxygen sensor 18 or executing the catalyst deterioration diagnosis of the catalyst 9. When the difference between the preset operating point with good fuel consumption rate and the current operating point of engine 2 is greater than or equal to a predetermined value, the engine torque correction amount and the motor torque correction amount are set to the preset fuel consumption rate. The operating point correction limit control is executed to increase or decrease the operating point at a predetermined rate to a certain amount smaller than the correction amount when the current operating point of the engine 2 is corrected to a good operating point. This is because when the operating point correction amount is large (when the difference between the preset operating point with a good fuel consumption rate and the current operating point of the engine 2 is large), the fluctuation of the engine torque becomes large, so that the engine This is to suppress fluctuations in engine torque by correcting the current operating point of No. 2 to a preset operating point with a good fuel consumption rate, but limiting it to a certain amount.
As shown in FIG. 4, in the operating point correction control (limitation of the operating point correction position), since the difference between the preset operating point having a good fuel consumption rate and the current operating point of the engine 2 is large, a constant amount (The current operating point is not corrected up to the preset operating point with good fuel consumption rate).
As shown in FIG. 5, in the operating point correction control and the operating point correction limit control (in the case of the engine torque increase correction), the current operating point of the engine 2 is shifted to a preset operating point with a good fuel consumption rate. The amount of increase in engine torque due to the operating point correction is the amount of torque that the motor generator 3 needs to absorb (the regenerative torque of the motor generator 3 (torque in the direction opposite to the amount of increase in engine torque) is absorbed). In the operating point correction limit control, the engine torque correction amount gradually increases in proportion to time, while the motor torque correction amount gradually decreases in proportion to time, and the engine torque correction amount and the motor torque correction amount are symmetrical. It has become a target.
As shown in FIG. 6, in the operating point correction control and the operating point correction limit control (in the case of engine torque reduction correction), the current operating point of the engine 2 is shifted to a preset operating point with a good fuel consumption rate. The amount of decrease in engine torque due to the operating point correction is the amount of torque that the motor generator 3 needs to absorb (the amount of assist torque of the motor generator 3 (torque in the direction opposite to the amount of decrease in engine torque) absorbs). In the operating point correction limit control, the engine torque correction amount gradually decreases in proportion to the time, while the motor torque correction amount gradually increases in proportion to the time, and the engine torque correction amount and the motor torque correction amount are symmetrical. It has become a target.

The operating point correction execution unit 33 corrects the target engine torque and the target motor torque based on a predetermined correction amount so that the current operating point of the engine 2 matches the preset operating point with a good fuel consumption rate. The operating point correction control is executed.
Specifically, the operating point correction executing unit 33 has a signal of the target engine torque and a signal of the target motor torque from the target torque calculation unit 28, and an adjusted engine torque correction amount from the operating point correction limiting unit 32. The signal, the signal of the adjusted motor torque correction amount, and the signal of the shifting state of the transmission 4 from the transmission control means 14 are input, and the corrected target engine torque and the target motor torque are obtained. Then, the operating point correction execution unit 33 outputs the corrected target engine torque signal to the engine output control unit 34. Further, the operating point correction execution unit 33 outputs the corrected target motor torque to the motor output request unit 35.
The engine output control unit 34 outputs a signal of the target engine torque input from the operation point correction execution unit 33 to the injector 10, the spark plug 11, and the throttle valve 12 so as to control the engine 2, and ignites the injector 10. It controls the plug 11 and the throttle valve 12.
The motor output request unit 35 outputs a signal of the target motor torque input from the operating point correction execution unit 33 to the hybrid control means 16 as an operating point correction request signal so as to control the motor generator 3. The hybrid control means 16 outputs a motor drive request signal based on the operating point correction request signal input from the engine control means 13 to the inverter 15. The inverter 15 outputs a motor voltage adjustment signal based on the motor drive request signal input from the hybrid control means 16 to the motor generator 3 to control the motor generator 3.

That is, in the first embodiment, the oxygen sensor failure diagnosis or the catalyst deterioration diagnosis periodically changes the rich state and the lean state of the fuel injection and diagnoses from the responsiveness, so that the fuel can be injected as expected. The engine load needs to be stable.
However, if the engine torque is changed in the operating point correction control, the fuel injection state may change, and the engine state may not be suitable for the oxygen sensor failure diagnosis or the catalyst deterioration diagnosis.
Therefore, by suppressing the factors that change the engine state and preparing an environment in which the oxygen sensor failure diagnosis or the catalyst deterioration diagnosis can be easily performed, the oxygen sensor failure diagnosis or the catalyst deterioration diagnosis can be completed at an early stage when the vehicle 1 is used.

Next, the operating point correction limitation control according to the first embodiment will be described with reference to the flowchart of FIG.
As shown in FIG. 3, when the program of the engine control means 13 starts (step A01), the oxygen sensor failure diagnosis unit 25 first determines whether or not the execution condition of the oxygen sensor failure diagnosis is satisfied (step A02). ).
If the step A02 is YES and the execution condition for the oxygen sensor failure diagnosis is satisfied, the operating point correction limiting unit 32 executes the operating point correction limiting control (step A03).
In the execution of the operating point correction limit control in step A03, for example, there are the following two methods. In the first execution, the correction amount of the current operating point of the engine 2 is gradually increased to slowly reach the target operating point. As the second execution, if the difference between the preset operating point with good fuel consumption rate and the target operating point is large, the operating point where the fluctuation of the engine torque can be tolerated (the preset operating point with good fuel consumption rate). The current operating point of the engine 2 does not reach the point) as the target operating point, and the target operating point is slowly reached (see FIGS. 4 to 6).
Then, it is determined whether or not the oxygen sensor failure diagnosis can be continued (step A04). The determination in step A04 confirms whether or not the predetermined conditions for executing the oxygen sensor failure diagnosis are satisfied, and on the other hand, if the conditions deviate from the preset diagnostic conditions, the diagnosis is terminated once.
If this step A04 is YES and the oxygen sensor failure diagnosis can be continued, it is determined whether or not the oxygen sensor failure diagnosis is completed (step A05).
If this step A05 is NO and the oxygen sensor failure diagnosis is not completed, the process returns to step A04.
When this step A05 is YES and the oxygen sensor failure diagnosis is completed, when the step A02 is NO and the oxygen sensor failure diagnosis execution condition is not satisfied, and when the step A04 is NO and the oxygen sensor failure diagnosis is completed. If is not sustainable, it is determined whether or not the catalyst deterioration diagnosis execution condition is satisfied (step A06).
If this step A06 is YES and the catalyst deterioration diagnosis execution condition is satisfied, the operating point correction limit control is executed (step A07).
In the execution of the operating point correction limit control in step A07, for example, there are the following two ways. In the first execution, the correction amount of the current operating point of the engine 2 is gradually increased to slowly reach the target operating point. As the second execution, if the difference between the preset operating point with good fuel consumption rate and the target operating point is large, the operating point where the fluctuation of the engine torque can be tolerated (the preset operating point with good fuel consumption rate). The current operating point of the engine 2 does not reach the point) as the target operating point, and the target operating point is slowly reached (see FIGS. 4 to 6).
Then, it is determined whether or not the catalyst deterioration diagnosis can be continued (step A08). The determination in step A08 confirms whether or not the predetermined conditions for executing the catalyst deterioration diagnosis are satisfied, and on the other hand, if the conditions deviate from the preset diagnostic conditions, the diagnosis is terminated once.
If this step A08 is YES and the catalyst deterioration diagnosis can be continued, it is determined whether or not the catalyst deterioration diagnosis is completed (step A09).
If this step A09 is NO and the catalyst deterioration diagnosis is not completed, the process returns to step A08.
When this step A09 is YES and the catalyst deterioration diagnosis is completed, when the step A06 is NO and the catalyst deterioration diagnosis execution condition is not satisfied, and when the step A08 is NO, the catalyst deterioration diagnosis can be continued. If not, the operating point correction limit control is stopped (step A10).
After that, the program ends (step A11).

As a result, according to the configuration of the first embodiment, by suppressing the factors that change the state of the engine 2 and preparing an environment in which the oxygen sensor failure diagnosis or the catalyst deterioration diagnosis can be easily performed, the oxygen sensor can be used when the vehicle 1 is used. The failure diagnosis or catalyst deterioration diagnosis can be completed at an early stage, and the accuracy of the oxygen sensor failure diagnosis or catalyst deterioration diagnosis can be improved.
Specifically, the operating point correction limiting unit 32 is the operating point correction executing unit at least when the oxygen sensor failure diagnosis of the front oxygen sensor 17 and the rear oxygen sensor 18 is being executed or the catalyst deterioration diagnosis of the catalyst 9 is being executed. The predetermined correction amount of the operating point correction control of 33 is limited. Thereby, when the oxygen sensor failure diagnosis or the catalyst deterioration diagnosis is being executed, the change in the engine torque due to the operating point correction control can be limited so as to reduce the fluctuation in the engine torque.
Further, the operating point correction limiting unit 32 operates as an operating point correction amount limit when at least the oxygen sensor failure diagnosis of the front oxygen sensor 17 and the rear oxygen sensor 18 is being executed or the catalyst deterioration diagnosis of the catalyst 9 is being executed. The operating point correction execution unit 33 determines the engine torque correction amount for correcting the target engine torque of the operating point correction control of the correction execution unit 33 and the motor torque correction amount for correcting the target motor torque. The operating point correction limit control is executed to limit by increasing or decreasing at a predetermined rate. As a result, the current operating point of the engine 2 is gradually corrected so as to approach the target operating point, so that a large change in engine torque is performed when the oxygen sensor failure diagnosis is being executed or the catalyst deterioration diagnosis is being executed. Can be prevented from occurring.
Further, the operating point correction limiting unit 32 limits the operating point correction position by at least performing the oxygen sensor failure diagnosis of the front oxygen sensor 17 and the rear oxygen sensor 18 or executing the catalyst deterioration diagnosis of the catalyst 9. When the difference between the preset operating point with good fuel consumption rate and the current operating point of engine 2 is greater than or equal to a predetermined value, the engine torque correction amount and the motor torque correction amount are set to the preset fuel consumption rate. The operating point correction limit control is executed to increase or decrease the operating point at a predetermined rate to a certain amount smaller than the correction amount when the current operating point of the engine 2 is corrected to a good operating point. As a result, when the operating point correction amount is large (when the difference between the preset operating point with good fuel consumption rate and the current operating point of the engine 2 is large), the fluctuation of the engine torque becomes large, so that the engine torque fluctuates in advance. Fluctuations in engine torque can be suppressed by correcting the set operating point with a good fuel consumption rate by limiting it to a certain amount.

FIG. 7 shows Example 2 of the present invention.
In the second embodiment, the parts that perform the same functions as those in the first embodiment will be described with the same reference numerals.
The features of the second embodiment are as follows. That is, the operating point correction limiting unit 32 is the operating point of the operating point correction executing unit 33 at least when the oxygen sensor failure diagnosis of the front oxygen sensor 17 and the rear oxygen sensor 18 is being executed or the catalyst deterioration diagnosis of the catalyst 9 is being executed. Stop the correction control. This is to reduce the change in engine torque, complete the oxygen sensor failure diagnosis or catalyst deterioration diagnosis at an early stage, and improve the accuracy of the oxygen sensor failure diagnosis or catalyst deterioration diagnosis.
Here, stopping the operating point correction control means that the operating point of the engine 2 is not corrected (the correction amount is not added), or the correction amount of the operating point of the engine 2 is set to zero (0). It may be corrected as (= not corrected as a result).

Hereinafter, the stop of the operating point correction control (stop of the operating point correction) in the second embodiment will be described with reference to the flowchart of FIG. 7.
As shown in FIG. 7, when the program of the engine control means 13 starts (step B01), the oxygen sensor failure diagnosis 25 first determines whether or not the oxygen sensor failure diagnosis execution condition is satisfied (step B02).
If the step B02 is YES and the oxygen sensor failure diagnosis execution condition is satisfied, the operating point correction limiting unit 32 stops the operating point correction control for the operating point correction executing unit 33 (step B03).
Then, it is determined whether or not the oxygen sensor failure diagnosis can be continued (step B04). The determination in step B04 confirms whether or not the predetermined conditions for executing the oxygen sensor failure diagnosis are satisfied, and on the other hand, if it deviates from the preset diagnostic conditions, the diagnosis is terminated once.
If this step B04 is YES and the oxygen sensor failure diagnosis can be continued, it is determined whether or not the oxygen sensor failure diagnosis is completed (step B05).
If this step B05 is NO and the oxygen sensor failure diagnosis is not completed, the process returns to step B04.
When this step B05 is YES and the oxygen sensor failure diagnosis is completed, when the step B02 is NO and the oxygen sensor failure diagnosis execution condition is not satisfied, and when the step B04 is NO and the oxygen sensor failure diagnosis is completed. If is not sustainable, it is determined whether or not the catalyst deterioration diagnosis execution condition is satisfied (step B06).
If the step B06 is YES and the catalyst deterioration diagnosis execution condition is satisfied, the operating point correction limiting unit 32 stops the operating point correction control for the operating point correction executing unit 33 (step B07).
Then, it is determined whether or not the catalyst deterioration diagnosis can be continued (step B08).
The determination in step B08 confirms whether or not the predetermined conditions for carrying out the catalyst deterioration diagnosis are satisfied, and on the other hand, if it deviates from the preset diagnostic conditions, the diagnosis is terminated once.
If this step B08 is YES and the catalyst deterioration diagnosis can be continued, it is determined whether or not the catalyst deterioration diagnosis is completed (step B09).
If this step B09 is NO and the catalyst deterioration diagnosis is not completed, the process returns to step B08.
When this step B09 is YES and the catalyst deterioration diagnosis is completed, when the step B06 is NO and the catalyst deterioration diagnosis execution condition is not satisfied, and when the step B08 is NO, the catalyst deterioration diagnosis can be continued. If not, the operating point correction limiting unit 32 executes the operating point correction control with respect to the operating point correction executing unit 33 (step B10).
After that, the program ends (step B11).

As a result, in the second embodiment, when the oxygen sensor failure diagnosis or the catalyst deterioration diagnosis is being executed, the operation point correction control of the engine 2 is stopped, so that the change in the engine torque can be reduced and the oxygen sensor can be reduced. The failure diagnosis or catalyst deterioration diagnosis can be completed at an early stage, and the accuracy of the oxygen sensor failure diagnosis or catalyst deterioration diagnosis can be improved.

8 and 9 show Example 3 of the present invention.
In the third embodiment, the parts that perform the same functions as those in the first embodiment will be described with the same reference numerals.
The features of this Example 3 are as follows. That is, as shown in FIG. 8, in the engine control means 13, the correction amount adjusting unit 31 adopts the torque change reduction control unit 36 instead of the operating point correction limiting unit 32 of the first embodiment.
When at least the oxygen sensor failure diagnosis of the front oxygen sensor 17 and the rear oxygen sensor 18 is being executed or the catalyst deterioration diagnosis of the catalyst 9 is being executed, the torque change reduction control unit 36 changes the required torque of the vehicle 1. Torque change reduction control is executed in which the amount of change in motor torque is set larger than the amount of change in engine torque. This is because the required torque of the vehicle 1 is assisted by the motor torque of the motor generator 3 as much as possible, and the amount of change in the engine torque is controlled to the minimum.

Next, the torque change reduction control according to the third embodiment will be described with reference to the flowchart of FIG.
As shown in FIG. 9, when the program of the engine control means 13 starts (step C01), the oxygen sensor failure diagnosis 25 first determines whether or not the oxygen sensor failure diagnosis execution condition is satisfied (step C02).
If the step C02 is YES and the oxygen sensor failure diagnosis execution condition is satisfied, the torque change reduction control unit 36 executes the torque change reduction control for the operating point correction execution unit 33 (step C03).
In the execution of the torque change reduction control in step C03, for example, there are the following two methods. In the first execution, the correction amount of the current operating point of the engine 2 is gradually increased to slowly reach the target operating point. As the second execution, if the difference between the preset operating point with good fuel consumption rate and the target operating point is large, the operating point where the fluctuation of the engine torque can be tolerated (the preset operating point with good fuel consumption rate). The current operating point of the engine 2 is not reached up to the point) as the target operating point, and the engine 2 is slowly reached to the target operating point.
Then, it is determined whether or not the oxygen sensor failure diagnosis can be continued (step C04). The determination in step C04 confirms whether or not the predetermined conditions for executing the oxygen sensor failure diagnosis are satisfied, and on the other hand, if the conditions deviate from the preset diagnostic conditions, the diagnosis is terminated once.
If this step C04 is YES and the oxygen sensor failure diagnosis can be continued, it is determined whether or not the oxygen sensor failure diagnosis is completed (step C05).
If step C05 is NO and the oxygen sensor failure diagnosis is not completed, the process returns to step C04.
When this step C05 is YES and the oxygen sensor failure diagnosis is completed, when the step C02 is NO and the oxygen sensor failure diagnosis execution condition is not satisfied, and when the step C04 is NO and the oxygen sensor failure diagnosis is completed. If is not sustainable, it is determined whether or not the catalyst deterioration diagnosis execution condition is satisfied (step C06).
If this step C06 is YES and the catalyst deterioration diagnosis execution condition is satisfied, the torque change reduction control unit 36 executes the torque change reduction control for the operating point correction execution unit 33 (step C07).
In the execution of the torque change reduction control in step C07, for example, there are the following two methods. In the first execution, the correction amount of the current operating point of the engine 2 is gradually increased to slowly reach the target operating point. As the second execution, if the difference between the preset operating point with good fuel consumption rate and the target operating point is large, the operating point where the fluctuation of the engine torque can be tolerated (the preset operating point with good fuel consumption rate). The current operating point of the engine 2 is not reached up to the point) as the target operating point, and the engine 2 is slowly reached to the target operating point.
Then, it is determined whether or not the catalyst deterioration diagnosis can be continued (step C08). The determination in step C08 confirms whether or not the predetermined conditions for executing the catalyst deterioration diagnosis are satisfied, and on the other hand, if the conditions deviate from the preset diagnostic conditions, the diagnosis is terminated once.
If this step C08 is YES and the catalyst deterioration diagnosis can be continued, it is determined whether or not the catalyst deterioration diagnosis is completed (step C09).
If this step C09 is NO and the catalyst deterioration diagnosis is not completed, the process returns to step C08.
When this step C09 is YES and the catalyst deterioration diagnosis is completed, when the step C06 is NO and the catalyst deterioration diagnosis execution condition is not satisfied, and when the step C08 is NO, the catalyst deterioration diagnosis can be continued. If not, the torque change reduction control unit 36 stops the torque change reduction control (step C10).
After that, the program ends (step C11).

As a result, in the third embodiment, the torque change reduction control unit 36 is performing at least the oxygen sensor failure diagnosis of the front oxygen sensor 17 and the rear oxygen sensor 18 or the catalyst deterioration diagnosis of the catalyst 9, and the vehicle 1 When the required torque changes, torque change reduction control is executed in which the amount of change in motor torque is set larger than the amount of change in engine torque. As a result, the required torque of the vehicle 1 can be assisted by the motor torque of the motor generator 3 as much as possible, and the amount of change in the engine torque can be minimized.

The drive control device of the present invention is not limited to the hybrid vehicle, and can be applied to various vehicles.

1 vehicle (hybrid vehicle)
2 engine 3 motor generator 4 transmission 6 drive control device 8 exhaust passage 9 catalyst 13 engine control means (ECM)
14 Transmission control means (TCM)
15 Inverter 16 Hybrid control means (HCU)
17 Front oxygen sensor 18 Rear oxygen sensor 25 Oxygen sensor Failure diagnosis unit 26 Catalyst deterioration judgment unit 27 Best operating point setting unit 28 Target torque calculation unit 29 Operating point calculation unit 30 Operating point correction amount calculation unit 31 Operating point correction amount adjustment unit 32 Operating point correction limit unit 33 Operating point correction execution unit 34 Engine output control unit 35 Motor output request unit 36 Torque change reduction control unit

Claims (6)

In a vehicle drive control device including an engine and a motor generator, and an oxygen sensor for detecting the oxygen concentration in the exhaust gas of the engine.
Based on the oxygen sensor failure diagnosis of the oxygen sensor and the target engine torque and the target motor torque based on a predetermined correction amount so that the current operating point of the engine matches the preset operating point with a good fuel consumption rate. Execute the operating point correction control to correct,
The operating point correction control is a constant amount smaller than the correction amount when the current operating point of the engine is corrected to the preset operating point having a good fuel consumption rate when the oxygen sensor failure diagnosis is being executed. A vehicle drive control device, characterized in that the predetermined correction amount is limited until In a vehicle drive control device including an engine and a motor generator, and an oxygen sensor for detecting the oxygen concentration in the exhaust gas of the engine.
Based on the oxygen sensor failure diagnosis of the oxygen sensor and the target engine torque and the target motor torque based on a predetermined correction amount so that the current operating point of the engine matches the preset operating point with a good fuel consumption rate. Execute the operating point correction control to correct,
The operating point correction control is a vehicle drive control device, characterized in that, when an oxygen sensor failure diagnosis is being executed, the predetermined correction amount is increased or decreased at a predetermined rate to limit it. In a vehicle drive control device including an engine and a motor generator, and an oxygen sensor for detecting the oxygen concentration in the exhaust gas of the engine.
Based on the oxygen sensor failure diagnosis of the oxygen sensor and the target engine torque and the target motor torque based on a predetermined correction amount so that the current operating point of the engine matches the preset operating point with a good fuel consumption rate. Execute the operating point correction control to correct,
A vehicle drive control device characterized in that the operating point correction control is stopped when the oxygen sensor failure diagnosis is being executed. In a vehicle drive control device including an engine and a motor generator, the catalyst for purifying the exhaust gas of the engine and an oxygen sensor for detecting the oxygen concentration in the exhaust gas.
The target engine torque and the target motor torque are corrected based on a predetermined correction amount so that the catalyst deterioration diagnosis of the catalyst and the operating point having a good fuel consumption rate set in advance coincide with the current operating point of the engine. Execute with operating point correction control,
The operating point correction control is set to a constant amount smaller than the correction amount when the current operating point of the engine is corrected to the preset operating point having a good fuel consumption rate when the catalyst deterioration diagnosis is being executed. A vehicle drive control device, characterized in that the predetermined correction amount is limited until it becomes. In a vehicle drive control device including an engine and a motor generator, a catalyst for purifying the exhaust gas of the engine, and an oxygen sensor for detecting the oxygen concentration in the exhaust gas.
The target engine torque and the target motor torque are corrected based on a predetermined correction amount so that the catalyst deterioration diagnosis of the catalyst and the operating point having a good fuel consumption rate set in advance coincide with the current operating point of the engine. Execute with operating point correction control,
The operating point correction control is a vehicle drive control device, characterized in that, when the catalyst deterioration diagnosis is being executed, the predetermined correction amount is increased or decreased at a predetermined rate to limit it. In a vehicle drive control device including an engine and a motor generator, and equipped with a catalyst for purifying the exhaust gas of the engine and an oxygen sensor for detecting the oxygen concentration in the exhaust gas.
The target engine torque and the target motor torque are corrected based on a predetermined correction amount so that the catalyst deterioration diagnosis of the catalyst and the operating point having a good fuel consumption rate set in advance coincide with the current operating point of the engine. Execute with operating point correction control,
A vehicle drive control device characterized in that the operating point correction control is stopped when the catalyst deterioration diagnosis is being executed.