JP3019727B2 - Start control device for hybrid engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a start control apparatus for a hybrid engine, and more particularly to a start-up control apparatus for a hybrid engine when the amount of power stored in the battery is reduced after the vehicle is driven by the driving force of a motor that operates on battery power. The present invention relates to a start control device for a hybrid engine of a hybrid vehicle that drives an engine to charge or supply electric power to a motor.

[0002]

2. Description of the Related Art In recent years, electric vehicles (E) have been used as pollution-free vehicles.
V) is in practical use. An example of this electric vehicle (EV) is disclosed in, for example, Japanese Patent Application Laid-Open No. 4-331402. A hybrid vehicle (HEV) as an electric vehicle disclosed in this publication is one that supplies electric power from an engine via a battery or directly to an inverter and drives the motor to travel. When the temperature of the catalyst is low at the time of starting the engine, the vehicle runs only with the electric power from the battery without starting the engine. In the meantime, the catalyst is heated to a temperature at which it can be sufficiently operated, and the engine is started after the catalyst has reached the activation temperature. With this configuration, the pollution of the hybrid vehicle is further reduced.

[0003]

Incidentally, these hybrid vehicles are non-polluting vehicles ZEV (Zero Emissi).
on Vehicie) or ULEV (UL
Since there is a high demand for a traverse low emission vehicle, it is desired that the emission level of harmful substances in the exhaust gas at the time of starting be suppressed as low as possible. Further, when the hybrid vehicle shifts from the normal EV running to the hybrid running, the shift must be performed smoothly. By the way, in the Otto cycle engine as an auxiliary engine used in a hybrid vehicle, in the air-fuel ratio control, air-fuel ratio feedback control is performed in order to maintain the target air-fuel ratio in a stoichiometric region near the stoichiometric air-fuel ratio or a predetermined lean air-fuel ratio. Have been. In this case, an O ₂ sensor is used to detect the actual air-fuel ratio signal.
It should be noted that the full range O ₂ sensor is also used in a diesel cycle engine operated in a lean region.

Here, the entire range of the O ₂ sensor is set in the set temperature range (7.
Since it operates normally at (00 ° C. to 900 ° C.) (see FIG. 38), it is equipped with a heating means to promote and maintain the activation of the sensor. Further, the engine is equipped with an exhaust gas purifying device such as a three-way catalyst, which also exhibits a predetermined purifying action after the activation of the catalyst is completed. Equipped. Further, at the time of starting the engine, as shown in FIG. 39, from the time of engine start t1, until the entire O ₂ sensor or during catalyst activation is completed warming up of t2 and open loop zone E1 when cold, wherein In the Japanese Patent Application Laid-Open No. H11-157, the activation of the fuel is increased by driving the heating means of the sensor and the catalyst to promote the activation and to secure the ignition stability when the engine is cold. In this open loop area E1,
The air-fuel ratio feedback control was not performed, and the open-loop air-fuel ratio control using the map was performed.

However, as shown in FIG. 39, when the engine is started from a cold state and is in the open loop region E1, the air-fuel ratio is largely different from that in the feedback control region E2, and the fuel injection is accordingly performed. The amount was also likely to vary. In particular, the the open-loop zone E1 when cold, start increasing, overlap warming increase process, HC of cold-start time in the exhaust gas of the auxiliary engine, CO, apt to increase the emission levels of NO _X. In addition, when the engine is started from a cold state, a predetermined purifying action is not exhibited until the activation of the exhaust gas purifying device such as a three-way catalyst is not completed, which is a problem. Furthermore, the heater of the conventional whole area O ₂ sensor is:
As shown in FIG. 38, even after entering the feedback control area E2, the heater is driven by applying a constant voltage to activate the heater. However, as shown by the broken line, the engine is fully accelerated with a large exhaust gas flow rate as shown by the broken line. When entering, the exhaust gas flow rate suddenly increased,
The sensor temperature tends to decrease and the accuracy of the sensor tends to decrease, and conversely, the sensor temperature increases in the deceleration region where the exhaust gas flow rate is low, and the sensor tends to deteriorate early or break down, and there is a problem with the constant voltage application method. .

Furthermore, the heating mechanism for enabling the activation of these O ₂ sensors and the exhaust gas purification apparatus such as a three-way catalyst requires electrical energy, completion time of activation of the O ₂ sensor or a three-way catalyst mutual In this case, the time for wastingly consuming electric energy increases, which is also a problem. Furthermore,
It is also desired to reduce the total amount of exhaust gas emissions by minimizing the engine operating time and the number of engine starts of a hybrid vehicle. A first object of the present invention is to adjust the timing at which each of the oxygen sensor and the catalyst reaches the activation temperature or more when the engine is started, and to cool and reheat the oxygen sensor and the catalyst to cause unnecessary battery discharge. It is an object of the present invention to provide a start control device for a hybrid engine that can avoid the above problem and reduce the emission level of HC and the like in exhaust gas at the time of starting the engine. A second object of the present invention is to predict the temperature detected by the oxygen sensor, predict the temperature of the catalyst, and determine whether to start the engine based on the detected temperatures. It is an object of the present invention to provide a start control device for a hybrid engine that can improve the reliability of a determination value for starting the engine.

[0007] A third object, upon start timing of the engine is predicted, each of the oxygen sensor and catalyst are shifting the timing energization so that the activation temperature at the same time, by reheating the oxygen sensor and catalyst An object of the present invention is to provide a start control device for a hybrid engine that can avoid unnecessary battery discharge and reduce the emission level of HC and the like in exhaust gas at the time of starting the engine.

A fourth object of the present invention is to provide a start control apparatus for a hybrid engine according to claim 3 , wherein the temperature of the oxygen sensor is predicted, the temperature of the catalyst is predicted, and the start of the engine is predicted based on the detected temperatures. In particular, an object of the present invention is to provide a hybrid engine start control device capable of improving the reliability of a predicted value.

[0009]

[0010]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention provides an electric motor for driving wheels of a vehicle, a battery for supplying electric power to the electric motor, and electric power for at least the battery. An engine for driving a generator to supply the gas; an oxygen sensor provided in an exhaust path of the engine; first heating means for heating the oxygen sensor to an activation temperature and detecting the temperature of the oxygen sensor; A catalyst provided, a second heating means for heating the catalyst to an activation temperature and detecting the catalyst temperature, a charge state detection means for detecting a charge state of the battery, The engine start timing determining means for determining the start timing of the engine, and the oxygen sensor and the oxygen sensor when the engine start timing is determined by the engine start timing determining means. Based on the detected temperature of each of the catalysts, the first heating means or the second heating means is set at a second energization start timing after a lapse of a set time from a first energization start timing to one of the first heating means or the second heating means. The first energization control means for starting energization of the other of the heating means, the engine start time determination means determines that the engine is started, and the detected temperatures of the oxygen sensor and the catalyst are determined by the respective temperatures of the oxygen sensor and the catalyst. First engine start control means for starting the engine when the temperature is equal to or higher than the activation temperature.

According to a second aspect of the present invention, in the start control device for a hybrid engine according to the first aspect, the first control system is provided.
The heating unit includes a first heater that heats the oxygen sensor to an activation temperature and an oxygen sensor temperature detection unit that predicts the temperature of the oxygen sensor from a resistance value of the first heater,
The second heating means includes a second heater for heating the catalyst to an activation temperature and a catalyst temperature detecting means for predicting the temperature of the catalyst from a resistance value of the second heater. According to another embodiment of the present invention, the first energization control means sets the first energization start timing to one of the first and second heaters so that the oxygen sensor and the catalyst are simultaneously activated. From the time until the second energization start timing to the other of the first and second heaters may be determined . Another form of claim 1
Te, the first energization control means, so that the oxygen sensor and catalyst during the engine operation becomes an active temperature range, respectively, for controlling the energization or non-energization to the first and second heating means, and You can also.

According to a third aspect of the present invention, there is provided an electric motor for driving wheels of a vehicle, a battery for supplying electric power to the electric motor,
An engine that drives a generator to supply power to at least the battery, an oxygen sensor provided in an exhaust path of the engine, and first heating that heats the oxygen sensor to an activation temperature and detects the temperature of the oxygen sensor Means, a catalyst provided in the exhaust path, second heating means for heating the catalyst to an activation temperature and detecting the catalyst temperature, charged state detecting means for detecting a charged state of the battery, at least detecting the charged state Means for estimating the start time of the engine in accordance with the output of the means, wherein the oxygen sensor and the catalyst are at least simultaneously activated at the time predicted by the engine start time estimating means. Each of the first and second heating means is supplied to the first and second heating means based on the detected temperatures of the sensor and the catalyst.
And second energization control means for controlling the second predicted energization start timing, the engine start timing estimating means has already predicted the engine start timing, and the detected temperatures of the oxygen sensor and the catalyst have been adjusted by the oxygen sensor and the catalyst. Second engine start control means for starting the engine when the temperature is equal to or higher than each activation temperature.

According to a fourth aspect of the present invention, in the start control device for a hybrid engine according to the third aspect, the first control system is provided.
The heating unit includes a first heater that heats the oxygen sensor to an activation temperature and an oxygen sensor temperature detection unit that predicts the temperature of the oxygen sensor from a resistance value of the first heater,
The second heating means includes a second heater for heating the catalyst to an activation temperature and a catalyst temperature detecting means for predicting the temperature of the catalyst from a resistance value of the second heater. According to another aspect of the third aspect, the second energization control means responds to the outputs of the oxygen sensor temperature detection means and the catalyst temperature detection means so that the oxygen sensor and the catalyst are simultaneously activated. The first and second predicted energization start timings for the first and second heating means may be set based on the detected temperatures.
You. Another form of the second aspect 3, the start timing predicting means predicts the start timing of the engine in response to the rate of change of decrease in charging rate detected by said charging state detection means, and may be .

According to a third aspect of the present invention , the engine start timing estimating means predicts the engine start time estimating means from the first and second predicted energizing start times set by the second energizing control means. Further, the engine start time may be predicted based on the first and second power consumptions consumed by the first and second heating means until the engine start time . Another form 4 of claim 3
As, the second energization control means, the oxygen sensor and the catalyst is such that each becomes the activation temperature range, to control the energization or non-energization to the first and second heating means during the operation of the engine, It can also be.

[0015]

According to the first aspect of the present invention, the engine start timing judging means judges the engine start timing according to the output corresponding to the state of charge of the battery from the state of charge detection means,
When the first power supply control means determines that it is time to start the engine, a set time elapses from the first power supply start time to one of the first heating means and the second heating means based on the detected temperatures of the oxygen sensor and the catalyst. Control is performed to start the energization of the other of the first heating means and the second heating means at the second energization start time after the start, the first engine start control means determines that it is the engine start time, and the oxygen sensor and The engine is started when the detected temperature of each of the catalysts is equal to or higher than the activation temperature of each of the oxygen sensor and the catalyst. The first energization start time and the second energization start time are shifted for a set time.

Further, according to the invention of claim 2, according to claim 1,
The control device for a hybrid engine according to the above,
The first heating means functions as an oxygen sensor temperature detecting means for predicting the temperature of the oxygen sensor from the resistance value of the first heater, and the second heating means predicts the temperature of the catalyst from the resistance value of the second heater. Therefore, the first engine start control means takes in the detected temperatures of the oxygen sensor and the catalyst from these, and determines the start of the engine. Another form of one 請 Motomeko 1, so that the oxygen sensor and catalyst at the start of the engine is the activation temperature at the same time, the energization of the first power supply control means to the one of the first heating means and second heating means When the first energization start time to be started and the second energization start time to the other are shifted by a set time ,
Means that the oxygen sensor and the catalyst are simultaneously at the activation temperature . Another form of one 請 <br/> Motomeko 1, field where the first power supply control means is to control the energization or non-energization of the first and second heating means
In this case, the operation is performed such that the oxygen sensor and the catalyst are in the activation temperature range during the operation of the engine.

Furthermore, according to the third aspect of the present invention, the engine start timing is predicted by the engine start timing predicting means at least in accordance with the output corresponding to the state of charge of the battery from the charged state detecting means. By means, the first heating means and the second heating means are respectively controlled based on the detected temperatures of the oxygen sensor and the catalyst such that the oxygen sensor and the catalyst are simultaneously activated at the same time when the engine start time is predicted. The first and second predicted energization start timings are controlled, and the engine start timing is already predicted by the second engine start control means, and the detected temperatures of the oxygen sensor and the catalyst are activated by the respective activation of the oxygen sensor and the catalyst. Since the engine is started when the temperature is equal to or higher than the temperature, when the start of the engine is predicted, the first predicted energization start time and the second predicted energization start time are set. By time shifting, the oxygen sensor and catalyst is controlled to be the activation temperature at the same time.

Furthermore, according to the invention of claim 4 , according to claim 3,
The control device for a hybrid engine according to the above,
The first heating means functions as an oxygen sensor temperature detecting means for predicting the temperature of the oxygen sensor from the resistance value of the first heater, and the second heating means predicts the temperature of the catalyst from the resistance value of the second heater. Therefore, the first engine start control means takes in the detected temperatures of the oxygen sensor and the catalyst and predicts the start of the engine start. Furthermore,
According to another aspect of the third aspect, the second energization control unit detects the oxygen sensor and the catalyst in accordance with the outputs of the oxygen sensor temperature detection unit and the catalyst temperature detection unit so that the activation temperature of the oxygen sensor and the catalyst temperature of the catalyst are simultaneously increased. when the to set the respective first and second predictive energization start timing of the first and second heating means based on the temperature, the oxygen sensor and catalyst are simultaneously
It will be the activation temperature .

[0019] 請 Another form of second Motomeko 3, when the engine starting time prediction means has to predict the start timing of the engine in accordance with a decrease in the rate of change of the charging rate, the second based on the predicted value Engine start control means starts the engine.
Another form of the third 請 Motomeko 3, the engine starting time prediction means from the first and second prediction energization start timing to start timing of the engine, which is predicted by the engine starting time estimating means which is set by the second current control means in the case where the start timing of the engine based on the first and second power consumption consumed by the first and second heating means was you prediction start the second engine starting control means based on the predicted value of the engine I do. Another form of the fourth 請 Motomeko 3, when the oxygen sensor and catalyst second energization control means during operation of the engine is as respectively the activation temperature range, to the first and second heating means Controls energization or non-energization

[0020]

FIG. 1 shows a start control apparatus for a hybrid engine according to the present invention. The hybrid vehicle 1 shown in FIG. 1 runs as an electric vehicle (EV) with a motor 2 (EV).
Then, when the charging rate of the battery 3 decreases, the auxiliary engine 4 is driven, the generator 5 is turned, the battery is charged, and the traveling is continued in order to shift to hybrid traveling. The drive wheel 6 of the hybrid vehicle 1 is connected to the motor 2 via a transmission 7, the motor 2 is supplied with power from a battery 3, the battery 3 is charged by a generator 5, and the generator 5 transmits torque (not shown). It is connected to the auxiliary engine 4 via the system and charged when the engine is driven. The generator 5 includes a current control circuit 501. When the current control circuit 501 receives a start signal Ss of an engine control unit 20 described later, the generator 5 supplies a start current to the generator and drives the generator as a starter. It is configured to be able to.

The arrow F in FIG. 1 indicates the traveling direction. The motor 2 is an induction motor. A coil (not shown) in the motor is connected to the drive circuit unit 8, and a rotor (not shown) transmits torque to the transmission 7. The drive circuit unit 8 converts the current sent from the battery 3 to the motor 2 into AC power and drives the motor 2, and performs output adjustment according to the current control signal Si of the control unit 10. The auxiliary engine 4 is the engine control unit 2
0, a throttle valve (not shown) and a fuel injection valve (not shown) for supplying fuel are provided in the intake system, and an exhaust manifold 27, an exhaust pipe 28,
9. Equipped with a muffler (not shown). The control unit 10 and the engine control unit 2
0 is a main part of a microcomputer, and both are connected by a signal line so that signals can be exchanged with each other.

In particular, the catalytic converter 29 includes a well-known three-way catalyst 291 and a second heater 2 which is a catalyst heater on the upstream side thereof.
92. The three-way catalyst 291 detects HC, C in exhaust gas.
O by performing reduction treatment of oxidation and NO _X of, for purifying exhaust gases. The second heater 292 is connected to the control unit 10 via the second drive circuit 37. An O ₂ sensor 30 serving as an oxygen sensor that outputs an air-fuel ratio signal to the engine control unit 20 based on the O ₂ concentration in the exhaust gas is provided in the exhaust pipe 28. The O ₂ sensor 30 is an all-range air-fuel ratio sensor that outputs an air-fuel ratio signal A / F over the entire range from rich to lean. The first heater 301 can be output. First heater 301
Is the control unit 10 via the first drive circuit 36.
It is connected to the.

[0023] Here, the first driving circuit 36, as shown in FIG. 2, the power supply, the transistor 364, the first heater 301, the resistor R ₁ a configuration connected in series in this order. The control unit 10 is connected to the base end of a transistor 364 for opening and closing the power supply current via a diode 365.
Is connected. Here, the control unit 10 functions as oxygen sensor temperature detecting means for predicting the temperature of the oxygen sensor from the resistance value _RH of the first heater 301. That is,
The resistance _RH of the first heater 301 is detected by the resistance detection circuit 366 and output to the control unit 10. The resistance value R _H of the first heater 301, as shown in FIG. 3, O than to increase in proportion to the sensor temperature Ts of the _second sensor, it is possible to know the sensor temperature Ts than the resistance value R _H. On the other hand, the second heater 292 for activating the catalyst on the upstream side of the three-way catalyst 291 is connected to the control unit 10 via the second drive circuit 37.

Here, the second drive circuit 37 is configured similarly to the first drive circuit 36. Here, as shown in FIG. 4, the transistor 367 and the second heater 29 are connected to the power supply.
2, a configuration connected in series with resistor R ₁ in this order. The control unit 10 is connected via a diode 368 to a base end of a transistor 367 that opens and closes a power supply current. Here, the control unit 10 is a three-way catalyst 2
The temperature of 91 functions as a catalyst temperature detecting means for predicting the resistance R _K of the second heater 292. That is, the resistance R _K of the second heater 292 is detected by the resistance detection circuit 369, it is outputted to the control unit 10. The resistance value R _K of the second heater 292 as shown in FIG. 5, the three-way catalyst 2
Than it rises in proportion to the catalyst temperature T _K of 91, it is possible to know the catalyst temperature T _K than the resistance value R _K.

The control unit 10 is constituted by a microcomputer, and its main part is constituted by a load sensor 32 for outputting an opening / closing signal Sm from the main switch 31, an accelerator pedal depression amount θa signal to an input port thereof, and a vehicle speed V _V signal. Each driving state detecting means such as a vehicle speed sensor 33 that outputs a charge rate Vc signal of the battery 3 as a charging state detecting means, a brake sensor 35 that outputs a brake signal B, and the like are connected. Further, the output port of the control unit 10 is the motor 2
And is configured to output a current control signal Si. The engine control unit 20 takes in each operation state detection signal received by the motor control unit 10 to its input port via a signal line.

An output port of the engine control unit 20 outputs a current throttle opening θ _TH and an ignition timing θi signal in the ignition circuit 16 to an actuator 15 for driving a throttle valve (not shown) of the fuel supply means of the engine 4. Connected. Further, a control program of an engine control routine of FIG. 26 is stored and processed in a ROM (not shown) of the engine control unit 20. The ROM (not shown) of the control unit 10 stores the main routine of FIG. 17 and the traveling control subroutine of FIG.
Each control program such as the battery charging subroutine of FIGS. 20 to 25 is stored and processed. Here, the control unit 10 particularly has the following functions.

[0027] As the engine start timing determining means A1, to determine the start timing of the engine 4 in accordance with the charging rate signal V c of the battery sensor 34, a first power supply control means A2,
When it is determined by the engine start timing determining means A1 that the engine is to be started, the O ₂ sensor 30 and the three-way catalyst 29 are used.
1 based on the respective detected temperatures T _S and T _E.
Alternatively, the first heater 3 is set to the second energization start timing after a lapse of a set time from the first energization start timing to one of the second heaters 292.
01 or the power supply to the other to start the second heater 292, a first engine start control means A3, the engine start timing determining means A1 is determined that the start timing of the engine 4 and the O ₂ sensor 30 and the three-way catalyst 291 The respective detection temperatures are the activation temperatures T _S1 and T _{E1 of} the oxygen sensor and the catalyst.
At this time, the engine 4 is started.

Further, the temperature T of the first heater 301 is used as an oxygen sensor temperature detecting means A4 which forms a part of the first heating means.
_S is predicted from the resistance value R _H of the first heater, and the second heater 2 is used as catalyst temperature detection means A5 which forms a part of the second heating means.
92 and predicting the temperature T _E of the three-way catalyst 291 from the resistance value R _K of the second heater. In addition, the first energization control means A2 particularly starts the first energization to one of the first and second heaters 301 and 292 so that the O ₂ sensor 30 and the three-way catalyst 291 each have the activation temperature at the same time. From the time until the second energization start timing to the other of the first and second heaters is determined. Further, as the first energization control means A2, particularly, the O ₂ sensor 30 and the three-way catalyst 29 during the operation of the engine.
The energization or non-energization of the first and second heaters 301 and 292 is controlled so that 1 is within the activation temperature range, respectively.

Hereinafter, the operation of the start control device for the hybrid engine will be described in accordance with each control program. The control unit 10 and an engine control unit 20 which will be described later transmit a key-on signal S
Control is started by m. Control unit 10
In step a1 of the main routine in FIG.
After the operation check of various components and the initial setting for taking in various initial values, the process proceeds to step a2, where the current driving state data, that is, the accelerator pedal depression amount θa, the vehicle speed Vv, the charge rate Vc of the battery 3, the brake B, etc. The signal is fetched and stored in a predetermined area of a RAM (not shown). Then, the process proceeds to the traveling control subroutine of step a3.

As shown in FIG. 19, reads the accelerator pedal depression amount θa in step b1 is a running control subroutine, the target vehicle speed characteristic shown a target vehicle speed V _T of the corresponding accelerator pedal depression amount θa 6 in step b2 It is determined along the setting map m-1. Note that the target vehicle speed V _T shown in FIG.
Is set so as to prevent the vehicle from starting up to the first stepping amount θ1, to allow the vehicle to start slowly up to the second stepping amount θ2, and to allow normal running when the opening degree is larger. At step b3, the current vehicle speed signal Vv is read. In step b4, the vehicle speed difference of the current vehicle speed signal Vv and the target vehicle speed V _T to (= Vv-V _T) is calculated, then, the vehicle acceleration setting characteristics shown a vehicle body acceleration α in FIG. 7 from the vehicle speed difference maps m Determine along -2. Here, this vehicle acceleration α is
Actual vehicle speed signal Vv is greater than the target vehicle speed V _T, thus the vehicle speed difference is positive, while a negative indicating the need to decelerate the vehicle, the vehicle speed difference is negative, positive represents the need to accelerate the vehicle 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.

Further, here, the air resistance coefficient C, the front projected area A, the rolling resistance coefficient μ, the total weight W, and the power transmission efficiency η of the vehicle are set to predetermined values, and the gravitational acceleration g,
A unit estimation coefficient K1 (for example, 270) is set,
From these, the motor output PS is calculated using equation (1). PS = [{C × A × (Vv) ² + μ × W + α × W / g} × Vv] / (K1 × η) (1) Next, here, the unit approximate coefficient K2 ( For example, 73
5) The motor efficiency η _{MT R} and the motor operating voltage V _M are set, and the motor drive current value (motor energization amount) I is calculated from these using the equation (2).

I = (K 2 × PS) / (η _MTR × V _M ) (2) When reaching step b 5, a current control signal Si representing a motor drive current value (motor power supply amount) I Drive circuit unit 8
And the current is controlled so that the motor drive current of value I is supplied from the battery to the motor 2 via the drive circuit unit 8. Thus, the vehicle is increased or decreased the actual vehicle speed to the target vehicle speed V _T, and thus to maintain.
Therefore, even immediately after the start key is turned on, when the accelerator pedal opening exceeds the first depression amount θ1, the electric motor starts and the vehicle starts. After the execution of the traveling control subroutine, the process returns to step a4 of the main routine. In the main routine, a later-described battery charging subroutine is executed, and the process proceeds to step a5. Here, unless the main switch is turned off, the process returns to step a2, and the control is terminated by turning off the key. As shown in FIG. 20, in the battery charging subroutine, the current charging rate Vc of the battery 3 is fetched in steps s1 and s2, and the charging rate Vc is set to the specified value Vc.
₁ (for example, a charging rate of 20%), and if it does, the process proceeds to step s3 (see time td in FIG. 8); otherwise, the process proceeds to step s77.

In step s3, it is determined whether or not the flag Fc indicating that the battery is being charged, that is, the engine is being driven, is 1. If No, the process proceeds to step s4, and if Yes, the process proceeds to step s61. In step s4, the O ₂ sensor 30 and the three-way catalyst (EHC) 291
Of each of the temperatures T _S and T _E is executed. In this case, the resistance values R _S and R _E of the first and second heaters 301 and 292 are taken in, and the temperatures T _S and T _E corresponding to the respective resistance values are determined as shown in FIGS.
, And store it in a predetermined area. O ₂ sensor 3
0 and the temperature T _S of the three-way catalyst 291, after the detection processing of T _E, the detected temperature T _E of the step s5 three-way catalyst (EHC) 291 is determined whether below the activation temperature T _E1, Ye
If s exceeds step s6, the process proceeds to step s55.

At step s6, it is determined whether or not the temperature T _S detected by the O ₂ sensor 30 is lower than the activation temperature T _S1.
If step S7 is exceeded, the process proceeds to step s27. In step s7, the second heater 2 of the three-way catalyst (EHC) 291
Flag F _E indicating that the energization to 92 it is determined whether or not 1, the process proceeds to step s30 in electrical communication with the step s8 not being energized. In step s8, the first heater 3 of the O ₂ sensor 30
It is determined whether or not the flag F _S indicating that the power is being supplied is 01 at 01, and if the power is not supplied, the process proceeds to step s31 if the power is supplied to step s9.

In step s9, as in step s4, the temperatures T _S and T of the O ₂ sensor 30 and the three-way catalyst 291 are again increased.
Execute the detection process of _E. Then, based on the temperature T _E of the step s10 current three-way catalyst 291, a three-way catalyst 2
FIG. 9 shows the heating time t _E until 91 becomes the activation temperature T _E1 .
And the t _E calculated along the calculation map m-3 (shown by a characteristic diagram), based on the temperature T _S of the current O ₂ sensor 30 in step s11, to the O ₂ sensor 30 is activated the temperature T _S1 is calculated along the heating time t _S of the t _S calculation map m-3 in FIG. 10 (indicated by characteristic diagram). t _E , t _S calculation map m
-3 and m-4 are stored and stored in the ROM (not shown) of the control unit 10 in advance. When the process reaches step s12, it is determined whether the difference between the heating times is a predetermined time, for example, 1 or less. If No, the process proceeds to step s13. If Yes, the process proceeds to step s18. In steps s13 to s17, t
The difference t _d1 between _E and t _S is obtained, the flag F _K indicating that the first energization start control is being performed is set to 1, the energization timer value t _C is cleared, and the second heater 292 of the three-way catalyst 291 is energized. , the second heater energization flag F _E to 1, the process proceeds to step s31.

In step s31, it is determined whether or not a flag F _K indicating that the first energization start control is being performed is 1, and if control is being performed in step s
Otherwise, the process proceeds to step s37.

When step s32 is reached during the first energization start control, the energization timer value t _C is counted up by one, and in step s33, the current energization timer value t _C is determined by the energization start timing t _d1 (step S13). It is determined whether or not the time exceeds the set time. If not, the process returns to the main routine, and if it does, the process proceeds to step s34. In steps s34 to s36, the first heater 301 of the O ₂ sensor 30 is energized, the first heater energizing flag F _S is set to 1, and the first heater 301 is turned on.
The energization start control flag _FK is turned off, and the process returns to the main routine. When it is determined in step s31 that the flag F _K indicating that the first energization start control is being performed is off, that is, in the previous step s5, the three-way catalyst 291 is activated at the activation temperature _TE1.
Is exceeded, the process proceeds to step s55, where it is determined that the O ₂ sensor 30 is lower than the activation temperature T _S1 . Further, it is determined in step s56 whether or not the first heater 301 is energized. This is the case where the three-way catalyst 291 becomes _lower than the activation temperature TE1 after the first heater 301 is energized in this case.
This is to perform processing for controlling the three-way catalyst 291 to the activation temperature at the same time as the O ₂ sensor 30 without energizing the heater 292. The following steps s37 to s3
9, here, steps s9 to s11 are performed again.
Similarly, the O ₂ sensor 30 and the three-way catalyst (EHC) 29
Each temperature T _S of 1, performs detection of T _E, then, Figure current based on the temperature T _E of the three-way catalyst 291, the heating time to the three-way catalyst 291 is activated temperature T _E1 t _E 11 of t _E calculation map m-5 is calculated along the (indicated by characteristic diagram), further, on the basis of the temperature T _S of the current O ₂ sensor 30, O ₂ sensor 30 to the activation temperature T _S1 The heating time t _S is calculated along the t _E calculation map m-6 (shown by a characteristic diagram) in FIG.

The time of the heating to the start of the step s40 in the three-way catalyst 291 O ₂ determines whether exceeds the time until start of heating of the sensor 30, and return to No in the main routine, the Yes step s41, the s42 Then, the second heater 292 of the three-way catalyst 291 is energized, the second heater energizing flag _{FE is set} to 1, and the process returns to the main routine. In step s12 (see FIG. 21), t _E −
If t _S is equal to or less than 1 and the process reaches step s18, on the contrary, it is determined whether or not t _S −t _E is 1 or less.

When it is determined that t _S -t _E is 1 or less and there is no difference between the two heating times, the process proceeds to steps s19 to s21, and the first and second heaters 30 of the O ₂ sensor 30 and the three-way catalyst 291 are reached.
1 and 292 are energized together, and the second heater energizing flag F _E
And returns to the main routine of the first heater energization flag F _S together as one. On the other hand, if t _S -t _E reaches step s22 to s26 as greater than 1, here, t _S -t calculates the difference t _d2 of _E, sets the flag F _K showing a first energization start control during 1 Then, the value t _{C of the} energization timer is cleared, the energization flag F _S of the first heater 301 of the O ₂ sensor 301 is set to 1, and the process proceeds to step s43. As shown in FIG. 23, in step s43, it is determined whether the flag F _K indicating that the first energization start control is being performed is 1 or not, and the control proceeds to step s43.
Go to step S44, otherwise go to step s49.

When the current energization timer reaches step s44 during the first energization start control, the energization timer value t _C is counted up by one, and in step s45, the current energization timer value t _C is determined by the energization start timing t _d2 (step S22). It is determined whether or not the time exceeds the set time. If not, the process returns to the main routine, and if it does, the process proceeds to step s46. Step s46
Or by energizing the second heater 292 of s48 In the three-way catalyst 291, and sets the second heater energization flag F _E to 1, turns off the first energizing start control flag F _K, the process returns to Meinruchi. When it is determined in step s43 that the flag F _K indicating that the first energization start control is being performed is off, that is, in contrast to the processing in steps s37 to s42, the O ₂ sensor 30
Exceeds the activation temperature T _S1 and the three-way catalyst 291 is energized to the second heater 292 at a temperature _lower than the activation temperature T _E1 ,
Thereafter, the case where the O ₂ sensor 30 becomes _lower than the activation temperature T _S1 , in which case the first heater 301
O ₂ sensor 30 is a three-way catalyst without energizing the (EHC) 29
At the same time as step 1, a process for controlling the activation temperature is performed. Upon reaching the following steps s49 to s51, where, similar to step s9 to s11, the temperature T _S of the O ₂ sensor 30 and the three-way catalyst (EHC) 291, performs detection of T _E, then, the current Three-way catalyst 2
Based on the temperature T _E of 91, the heating time t _E until the three-way catalyst 291 reaches the activation temperature T _E1 is calculated along the t _E calculation map m-7 (shown by a characteristic diagram) in FIG. Furthermore, based on the temperature T _S of the current O ₂ sensor 30, the heating time t _S to O ₂ sensor 30 is activated the temperature T _S1 in calculating map m-8 in FIG. 14 (shown by characteristic line diagram) Calculate along.

In step s52, it is determined whether or not the time t _S before the heating of the O ₂ sensor 30 is started exceeds the time t _E until the heating of the three-way catalyst 291 is started. Proceeding to s53 and s54, the first heater 301 of the O ₂ sensor 30 is energized,
The first heater energizing flag F _{S is set} to 1 and the process returns to the main routine. In the above step s8, the O ₂ sensor 30
F indicating that the first heater 301 is energized.
_{If S} is 1, the processing from step s31 is executed directly.

[0042] As the flag F _E indicating that the energization to the second heater 292 of the three-way catalyst 291 in the above step s7 is 1, it reaches the step s30, wherein further, the first
The flag F _S indicating that the heater 301 is energized is set to 1
Is determined, the process returns to step s43 if No, and directly executes the processing of step s43 and subsequent steps. In step s6 described above, when the temperature T _S detected by the O ₂ sensor 30 exceeds the activation temperature T _S1 and the process reaches step s27, here, the flag F _E indicating that the second heater 292 of the three-way catalyst 291 is energized is used. Is determined to be 1 or not, and if No, step s2
The process proceeds to s29, and the second heater 292 is energized to
Set the heater energization flag F _E to 1, as it is in Yes return.

[0043] In step s5 described above, when the detected temperature T _E of the three-way catalyst 291 reaches step s55 determines that exceeds the activation temperature T _E1, where the detected temperature T _S of the O ₂ sensor 30 is activated It is determined whether the temperature is lower than T _S1 and No
Then, the process proceeds to steps s59 and s60, the engine start process, that is, the drive command D is output to the engine control unit 20, the engine driving flag Fc is set to 1, and the process returns to the main routine. On the other hand, it is determined that the temperature T _S detected by the O ₂ sensor 30 is lower than the activation temperature T _S1 , and the process reaches step s56. Here, the first O ₂ sensor 30 is used.
It is determined whether the flag F _S indicating that the heater 301 is energized is 1 or not, and during No, the process proceeds to steps s57 and s58 to perform energization processing for the first heater 301 and set the first heater energization flag F _S to 1 Is set, and in the case of Yes, the process directly returns to the main routine. When it is determined that the engine is being driven in step s3 with respect to the processing when the engine is not operating, the process proceeds to the processing in step s61 and subsequent steps shown in FIG.

The check is made whether the lower limit of the activation temperature T _E1 in step s61 in the three-way catalyst 291 (L) is detected the temperature T _E below, below the exceeds to step s62 proceeds to the step S69.

At step s62, the second catalyst 291
Flag F _E indicating that the current supply to the heater 292 is determined whether 1, the proceeds to step s63, s64 No, energizes the second heater 292 (point in Fig. 15 ta1), second heater energization flag F _E is set to 1, and if Yes, the process directly proceeds to step s65. Three-way catalyst 2 in step s61
When 91 lower the activation temperature T _E1 (L) of the process reaches Step s69 as above is detected temperature T _E, whether where the detected temperature T _E of the activation temperature of the upper limit of the three-way catalyst 291 (H) below If No, the process proceeds to step s70, and if Yes, the process directly proceeds to step s65. In step s70, the second
Determining one or not the heater energization flag F _E, clear proceeds 1 step s71, s72, and stops energizing the second heater 292 (as in FIG. 15 ta2), second heater energization flag F _E If No, the process proceeds directly to step s65. In step s65, O ₂ of the lower limit sensor 30 activation temperature (L) T _S1 for detecting the temperature T _E is determined whether below, below the exceeds to step s66 step s7
Proceed to 3.

In step s66, the first O ₂ sensor 30
It is determined whether the flag F _S indicating that the heater 301 is energized is 1 or not, and if No, the process proceeds to steps s67 and s68 to energize the first heater 301 (time point ta3 in FIG. 16). _S is set to 1, and if Yes, the process returns to the main routine. O in step s65
If the lower limit of the activation temperature T _S1 of the _second sensor 30 (L) reaches a step s73 as the detected temperature T _S is above, where the detection of O ₂ activation temperature of the upper limit sensor 30 (H) T _S2 temperature T _S Is determined to be less than or equal to, and if No, step s7
If Yes in 4, return to the main routine. In step s74, it is determined whether or not the first heater energizing flag F _S is 1. In step 1, the process proceeds to steps s75 and s76, the energization of the first heater 301 is stopped, and the first heater energizing flag F _{S is set.}
Is cleared, and if No, the process returns to the main routine. Current charging rate Vc of battery 3 as described above
There to If below a prescribed value Vc _1, the charging rate Vc exceeds the prescribed value Vc _1, the process proceeds to step s77.

Here, the charging rate Vc is equal to the first specified value Vc.
_It is determined whether the value exceeds a second specified value Vc ₂ exceeding ₁ (for example, a charging rate of 25%), and the process returns to the main routine during No, and proceeds to step s78 if it exceeds. Here, it is determined whether or not the engine drive flag F _C is 1, and returns to the main routine in No, Step Yes s79, s8
Go to 0. Here, by stopping the output of the engine drive signal D to the engine stop process, to clear the engine driving flag F _C, the process proceeds to step s81. Here, it is determined whether or not the second heater 292 of the three-way catalyst 291 is energized. If the current is not energized, the process proceeds to step s84.
Go to 83. Here, the energization of the second heater 292 is stopped, to clear the flag F _E, the process proceeds to step s84. Here, it is determined whether or not the first heater 301 of the O ₂ sensor 30 is energized. If the energization is not performed, the process returns to the main routine. If the energization is performed, the process proceeds to steps s85 and s86. Here, the energization of the first heater 301 is stopped, the flag F _S is cleared, and the process returns to the main routine.

On the other hand, the engine control unit 20
Control is also started by key-on, and in step c1, it is determined whether or not the engine drive signal D is input from the control unit 10, and when it is not input, the engine stop processing is performed or confirmed in step c3. move on. When the engine drive signal D reaches the step c2 at the time of input, the vehicle speed Vv,
The accelerator pedal depression amount θa and other various operating state information of the engine are fetched, and the process proceeds to step c4. Here, it is detected whether the engine is operating, and when the engine is not operating, step c
In step 6, the operation proceeds to step c5. In step c6, control processing at the time of starting the engine is performed. For example, setting the target throttle opening θ _TRG to the starting throttle opening,
The ignition timing is set to the ignition timing for starting, and in step c7, the current control circuit 5 of the generator 5 is operated to start the engine.
01, a starter drive signal Ss is output, a battery current is supplied to the generator 5, the generator 5 is driven as a starter, and the engine is started. As a result, the engine is started, the generator 5 is driven, and charging of the battery 3 is started.

When step c5 is reached after the engine is started, it is determined whether the vehicle speed signal Vv is lower than the set speed Vα and the vehicle is running at a low speed, decelerating, or stopped.
If yes, go to step c10, otherwise go to step c8. In step c8, it is determined whether or not the accelerator pedal depression amount θa is less than a set load (here, the fully closed determination value θc).
Go to 9. In step c10, it is assumed that the current driving range is such that the vehicle speed is less than the set speed Vα or the accelerator pedal depression amount θa is less than the set load (here, the fully closed determination value θc).
The engine is controlled to idle operation (the target throttle opening θ _TRG is set to θ _LOW ), and the process proceeds to step c11. As described above, in the low speed and deceleration operation ranges, the engine is set to the idle operation, power generation is suppressed, and the deceleration braking energy on the motor side can be efficiently collected. In step c9, it is determined that the current operation range is not the low speed or deceleration operation range, and the engine is controlled so as to be in the normal operation (the target throttle opening θ _TRG is set to θ _HIGH ), and the process proceeds to step c11.

In step c11, it is determined whether or not the current throttle opening θ _TH exceeds the target throttle opening θ _TRG .
If it exceeds, the throttle opening is narrowed to the closing side by a unit amount, and if it falls below, the throttle opening is opened to the opening side by a unit amount, and the process proceeds to step c12. In step c12, the target throttle opening θ _TRG is set. The engine control including the ignition timing control, the fuel injection control and the like according to the above is executed, and the process proceeds to step c13. Here, step c unless the main switch 31 is turned off.
Return to 1 and end the control by key-off.

Next, a start control device for a hybrid engine according to a second embodiment will be described. A hybrid vehicle equipped with the start control device for a hybrid engine according to the second embodiment includes many components similar to those of the hybrid vehicle 1 shown in FIG. 1 except that the function of the control unit 10 is different. Here, illustration is omitted, and the same members are denoted by the same reference numerals, and redundant description is omitted. In the ROM (not shown) of the control unit 10 in the second embodiment, the main routine of FIG. 17 and the traveling control subroutine of FIG. 19, FIG. 18, FIG. 20 to FIG.
6 (or FIG. 37) are stored and processed in each control program of the battery charging subroutine.

The control unit 10 has the following functions. As the engine starting time prediction unit B1, predicts the start timing of the engine 4 in accordance with the charging rate signal V c of at least a battery sensor 34, the second
Each of the O ₂ sensor 30 and the three-way catalyst 291 serves as the energization control means B2 such that the O ₂ sensor 30 and the three-way catalyst 291 have the activation temperatures at the same time at least at the time predicted by the engine start time prediction means B1. The first and second predicted energization start timings for the first and second heating means are controlled based on the detected temperature. As the second engine start control means B3, the engine start timing is already determined by the engine start timing prediction means B1. Predicted and O ₂ sensor 3
The engine 4 is started when the detected temperatures T _S and T _{E of the} zero and three-way catalyst 291 are equal to or higher than the respective activation temperatures of the O ₂ sensor 30 and the three-way catalyst 291. Furthermore, as an oxygen sensor temperature detector B4 which form part of the first heating means, to predict the temperature T _S of the first heater 301 from the resistance value R _H of the first heater, the catalyst forming part of the second heating means as the temperature detecting means B5, predicts the temperature T _E of the second heater 292 and the three-way catalyst 291 from the resistance value R _K of the second heater.

[0053] Further, as the second power supply control unit B2, in particular, as the O ₂ sensor 30 and the three-way catalyst 291 is activated temperature simultaneously respectively, to detect the temperature of each of the O ₂ sensor 30 and the three-way catalyst 291 Based on this, first and second predicted energization start timings for the first or second heaters 301 and 292 are set. Further, as the start timing predicting means B1, the start timing of the engine is predicted, in particular, according to the rate of change of the decrease in the charge rate signal Vc of the battery sensor 34.

Further, as the start timing estimating means B1, in particular, the engine start timing estimating means B1 from the first and second predicted energizing start times set by the second energizing control means B2.
1st and 2nd by the engine start time predicted by
The engine start timing is predicted based on the first and second power consumptions consumed by the heaters 301 and 292. Furthermore,
In particular, the first and second heaters 301 and 302 serve as the second energization control means B2 so that the O ₂ sensor 30 and the three-way catalyst 291 each have an activation temperature range during operation of the engine.
The energization or non-energization of the power supply 92 is controlled. The operation of the hybrid engine start control device according to the second embodiment will be described below in accordance with each control program.

The main routine and the running control subroutine performed by the control unit 10 of the second embodiment are the same as the main routine (see FIG. 17) and the running control subroutine (see FIG. 19) of the first embodiment. Duplicate description is omitted. Further, when the control unit 10 reaches step a4 in the middle of the main routine, the battery charging subroutine is executed. Except for the above, the process is executed in the same manner as the battery charging subroutine of the first embodiment. For this reason, the description of the steps s1 to s86 of the battery charging subroutine will be simplified with reference to FIGS. 18 and 20 to 25. Further, step s7 of the battery charging subroutine
FIGS. 32 to 37 (or FIG. 38) show the part including 7 'and the flowchart after step s101, and will be described in order.

In the battery charging subroutine according to the second embodiment, first, as shown in FIG.
At 6, the current charging rate Vc of the battery 3 falls below the _first specified value Vc ₁ , the engine is not running, and the O ₂ sensor 3
The temperatures T _S and T _{E of the} zero and three-way catalyst 291 are the activation temperature T.
It is determined that less than _S1, T _E1, the flow proceeds to step s7. In steps s7 to s11, the second heater 29 of the three-way catalyst
2, the O ₂ both the first heater 301 of the sensor 30 is below the activation temperature T _S1, T _E1, the temperature T _S of the O ₂ sensor 30 and the three-way catalyst 291 based on the T _E, O ₂ sensor 3
The heating times t _E and t _S until the 0 and the three-way catalyst 291 reach the activation temperatures T _S1 and T _E1 are calculated, and the process proceeds to step s12. On the other hand, one of the first heaters 301 of the O ₂ sensor 30 determines If the activation temperatures T _S1 and T _E1 are exceeded, step s27
In steps s30, the other is switched during energization.

In steps s12 to s21, a difference t _d1 between the heating times t _E and t _S is determined. If the difference is a predetermined time, for example, 1 or more, the second heater 2 of the three-way catalyst 291 is determined.
92, the difference t _d1 is 1 or less and the heating time t
_When the difference t _d2 between _S and t _E is 1 or less, both heaters are driven on the assumption that there is no difference between the heating times t _E and t _S of both heaters. Furthermore,
If the difference t _d2 between the heating times t _S and t _E is 1 or more in step s18, the process proceeds to steps s22 to s26, and the O ₂ sensor 30
Of the first heater 301 is energized. Three-way catalyst 291
Of the second heater 292 in step s17 to s3
Upon reaching the 1 to s36, wherein the heating time t _E, waits for the elapse of the difference t _d1 of t _S, when passed, O ₂ sensor 3
The first heater 301 of 0 is energized. This O ₂ sensor 30
After the first heater 301 energized again reached step s31, the processing proceeds to step s37 to 42, wherein again until the current of the three-way catalyst 291 and the O ₂ sensor 30 is activated the temperature T _E1, T _S1 heating time t _E, and calculates the t _S, the heating time t _E is energizing the second heater 292 when the three-way catalyst 291 above the t _S.

When the first heater 301 of the O ₂ sensor 30 is energized and the process proceeds from step s26 to steps s43 to s48, the process waits for the difference t _d2 between the heating times t _S and t _E to elapse. Second heater 29 of three-way catalyst 291
2 is energized. The second heater 292 of the three-way catalyst 291
After the power is supplied to step s43, step s43 is reached again, and step s49 is reached.
When the process proceeds to 54, the current three-way catalyst 29 is again
The heating times t _E and t _S until the 1 and O ₂ sensors 30 reach the activation temperatures T _E1 and T _S1 are calculated, and when the heating time t _S exceeds t _E , the first heater 301 of the O ₂ sensor 30 is turned on. Turn on electricity. Further, it is determined that at step s5, the detected temperature T _E of the three-way catalyst 291 is above the activation temperature T _E1 Step s55
Go to s60. Here, when the detected temperature T _S of the O ₂ sensor 30 is below the activation temperature T _S1, and drives the first heater 301 of the O ₂ sensor 30, wait for the above, the engine starting process exceeds.

If it is determined in step s3 that the engine is being driven, the process proceeds to steps s61 to s64. Now the detected temperature T _E of the three-way catalyst 291 is lower than the lower limit of the activation temperature (L), to drive the second heater 292 of the three-way catalyst 291, it exceeds the detection of the three-way catalyst 291 in step s69 to s72 wait temperature T _E is from above the activation temperature (H) of the upper and stops the energization of the second heater 292 of the above. When the temperature T _S of the steps s65 to 68 in O ₂ sensor 30 is below the activation temperature T _S1, and drives the first heater 301 of the O ₂ sensor 30, detects the temperature T _S of the O ₂ sensor 30 in step s73 to 76 Wait for the temperature to exceed the upper limit activation temperature (H), and when it exceeds, the energization of the first heater 301 is stopped. As described above, when the current charging rate Vc of the battery 3 falls below the specified value Vc ₁ , the charging rate Vc is changed to the specified value Vc _1.
If greater than c _1, step than step s2 s7
Go to 7 '(see FIG. 32).

[0060] As shown in FIG. 32, in step s77 ', it is determined whether or not above a second predetermined value Vc ₂ (e.g. charging rate 25%) of charging rate Vc exceeds the first predetermined value Vc _1, Until it exceeds, the process proceeds to step s101, and if it exceeds, the process proceeds to step s78. Steps s78 to s86
Then, since the current value exceeds the second specified value Vc ₂ , if the engine is being driven, the engine is stopped, and the three-way catalyst 291 and the heaters 292 and 301 of the O ₂ sensor 30 are operated.
When the power is supplied, the power supply to each heater is stopped. On the other hand, as shown in FIG. 33, the process proceeds to step s101 as the charging rate Vc is between prescribed value Vc ₁ and Vc _2, where,
It is determined whether the engine driving flag F _C is 1, when the engine is inoperative in step s102, during operation proceeds to step s61 to 76 shown in FIG. 24. Incidentally, the processing proceeds to step s61 to 76 during engine operation, as described above, the activation of the detected temperature T _E of the three-way catalyst 291 is lower limit temperature T _{E 1} (L) and the upper limit of the activation temperature T _E2 (H) On / off control of the second heater 292 is performed so that the temperature T _S of the O ₂ sensor 30 is maintained between the lower limit activation temperature T _S1 (L) and the upper limit activation temperature T _S2 (H). The first heater 301 is controlled as described above.

When step s102 is reached when the engine is not operating, a flag Fi indicating that the second energization start control is being performed is performed here.
Is determined to be 1 or not. If No, the process proceeds to step s103. If Yes, the process proceeds to step s140. In step s103, the process enters the process of calculating tv for the time when the charging rate V1 at which the engine needs to be started is reached. As shown in FIG. 36, in the subroutine for calculating the time tv until the charging rate V1 at which the engine needs to be started, the current charging rate Vc of the battery 3 is acquired in step s201. At step s202, the charging rate Vc is sequentially fetched every predetermined sampling time (for example, 60 seconds), and the current value Vc ₀ , the previous value Vc ₁ ...
Update c _(n-1) sequentially. Then each step s203, n-1 times the average difference value V _A of difference values V _A0 of the previous value and the current value (= Vc ₁ -Vc _{0) [= (V A (n-2} ) + ···· +
V _A0 ) / (n-1)]. In step s204, based on the current state of charge Vc ₀ and the average difference value _VA that is the rate of change of the decrease in the state of charge, each average difference value _{VA in} FIGS. 27 and 28 is used.
Tv calculation map m-9 (V _A = 1) or m-10 (V _A
= 2) (each shown in a characteristic diagram), and the charging rate is V
A time tv until _C <V1 is calculated, and the same value is obtained as a predicted engine start time at the present time.
Return to 04.

[0062] performing each temperature T _S of the step s104 O ₂ sensor 30 and the three-way catalyst (EHC) 291, the detection processing of T _E as in step s4. Then, step s
At 105, the heating times t _S and t _E required for the current temperatures T _S and T _E of the O ₂ sensor 30 and the three-way catalyst 291 to reach the activation temperatures T _S1 and T _E1 are determined in the same manner as steps s38 and s39. The calculation is performed, and the process proceeds to step s106. Here, it is determined whether or not the current heating time t _E of the three-way catalyst 291 is shorter than the predicted engine start time tv.
If it exceeds, the process proceeds to step s135. Step s135
Then, it is determined whether or not the heating time t _S of the O ₂ sensor 30 is lower than the predicted engine start time tv.
If it exceeds 25, steps s136 to s13
Go to 9. Heating time t from engine start prediction time tv
_{When it} is determined that both _S and t _E are large and the process reaches steps s136 to s139, the O ₂ sensor 30 and the first and second heaters 30 of the three-way catalyst (EHC) 291 are used here.
1 and 292 are driven to set the first and second heater energizing flags F _S and F _E to 1, respectively, and return to the main routine.

On the other hand, assuming that the heating time t _E of the three-way catalyst 291 is shorter than the predicted engine start time tv, step s1
07, where it is determined whether the heating time t _S of the O ₂ sensor 30 is below the predicted engine start time tv, and if it is below, the process returns to the main routine.
Proceed to 108. In step s108, it is determined whether the flag F _S indicating that the first heater 301 of the O ₂ sensor 30 is energized is 1 or not. If No, the process proceeds to steps s109 to s110 to energize the first heater 301 of the O ₂ sensor 30; sets the first heater energization flag F _S 1, directly in Yes, the process proceeds to step s111. In steps s111 to s114, the difference ti1 between the heating times t _S and t _E of the O ₂ sensor 30 and the three-way catalyst 291 is obtained, the second power supply start control flag Fi is set to 1, and the power supply during the second power supply start control is performed. The value tc of the timer for counting the middle elapsed time is cleared, the value tc of the timer is incremented by 1, and the process proceeds to step s115.

In step s115, the timer value tc is set to t
Wait for the difference ti1 of _S− t _E to be exceeded, and if so, proceed to steps s116 and s117, where the second
Drives the heater 292, and sets the second heater energization flag F _E to 1, the process proceeds to step s118. Step s1
18 and s119 in the temperature T _E of the three-way catalyst 291 exceeds the activation temperature T _{E 1,} the process proceeds only to step s120 if the temperature T _S of the O ₂ sensor 30 exceeds the activation temperature T _S1,
Otherwise, return to the main routine. In steps s120 to s122, engine start processing, that is,
A drive command D is output to the engine control unit 20, the engine drive flag Fc is set to 1, the second power supply start control flag Fi is cleared, and the process returns to the main routine.

[0065] proceeds to the aforementioned step s106 from s135, wherein the heating time t _S of the O ₂ sensor 30 is advanced to step s125 as below tv starting predicted timing of the engine, wherein the second heater energization flag F _E Is determined to be 1 or not, and if No, the process proceeds to steps s126 and s127,
To drive the second heater 292 of the three-way catalyst 291, and sets the second heater energization flag F _E to 1, directly in Yes proceeds to step s128.

In steps s128 to s131, the difference ti2 between the heating times t _E and t _S of the three-way catalyst 291 and the O ₂ sensor 30 is obtained, the second energization start control flag Fi is set to 1, and the second energization start time is set. The value tc of the timer for counting the elapsed time is cleared, the value tc of the timer is incremented by 1, and the process proceeds to step s132. Step s132 the timer value tc waits for the above differences ti2 of t _E -t _S, than the process proceeds to step S133, s134, drives the first heater 301 of the O ₂ sensor 3, the first heater energization flag F
_S is set to 1, the routine proceeds to step s118, and the processing proceeds to the engine start determination processing. Step s1 shown in FIG.
02, the flag Fi indicating that the second energization start control is being performed.
There In step s140 it is determined in 1, the second heater energization flag F _E is determined whether 1 here, Yes
Then, the process advances to step s141.

In step s141, it is determined whether the first heater energizing flag F _S is 1 or not.
8, the process proceeds to an engine start determination process. If No, the process proceeds to step s114, where the timer value tc is set to the difference ti1
When the value exceeds, the process proceeds to the process of driving the second heater 292. On the other hand, if at step s140 is the second heater energization flag F _E proceeds to step s142 off, here, waits for the first heater energization flag F _S is set to 1, when set to 1 step Proceeds to s131, where the timer value t
When c exceeds the difference ti2, the process proceeds to the process of driving the first heater 301. In the above description, the time t until the charge rate V1 required to start the engine according to the second embodiment becomes 1 and 1 is reached.
v In the subroutine for calculating the (see FIG. 36) captures the charging rate Vc of the battery 3 for each sample time, calculates the average difference value V _A of difference values V _A0 of the previous value and the current value of the charging rate Vc, the charge The time tv until the charging rate becomes Vc <V1 is determined as the predicted engine start time based on the average difference value _VA , which is the rate of change of the rate reduction, and the current charging rate Vc ₀ . Instead of this processing, the calculation of the time tv until the state of charge V1 at which engine start is required as a modification of the second embodiment may be performed by a subroutine shown in FIG.

The charging rate V1 required to start the engine shown in FIG. 37
Is between charging rate Vc is specified value Vc ₁ and Vc ₂ in the subroutine of tv calculating the time until the property during the engine non-operation, the flag Fi indicating the second energization start control in the off (step s101 , S102), and enters a process of calculating tv at a time when the charging rate V1 at which the engine needs to be started is reached. In step s211, the current charging rate Vc of the battery 3 is fetched. In steps s212 and s213, the charging rate Vc is fetched every predetermined sampling time as in steps s202 and s203, and the current value Vc ₀ and the previous value Vc _1.
... n-1 times the previous value Vc _(n-1) is sequentially updated, and then
N−1 of the difference value V _A0 (= Vc ₁ −Vc ₀ ) between the previous value and the current value
Average difference value V _A [= (V _{A (n−2)} +... + V _A0 )
/ (N-1)]. Steps s214, s21
In 5, the respective temperatures T _S and T _E of the O ₂ sensor 30 and the three-way catalyst (EHC) 291 are detected, and then the three-way catalyst 291 is activated based on the current temperature T _E of the three-way catalyst 291. Heating time t _{E to} reach T _E1 and O ₂ sensor 30
There calculates the heating time t _S until the activation temperature T _S1 as in step s10, s11.

In step s216, the electric powers V _S and V _E consumed by the heating times t _S and t _E until the O ₂ sensor 30 and the three-way catalyst 291 reach the activation temperatures T _S1 and T _E1 are shown in FIGS. 310 V _S, is calculated along the V _E calculation map m-11, m-12 (indicated by characteristic diagram). The calculation maps of the power consumption V _S and V _E used here are stored in the control unit 1 in advance.
0 is stored in the ROM (not shown). In step s217, the current charging rate Vc ₀ and power consumption V _S ,
Vc from _{V E 0 - (V E +} V S) is calculated and equivalence with the charging rate V
The time tv until Vc ≦ V1 is calculated from the average difference value _VA that is the rate of change of c, and the process proceeds to step s104. Note that the power consumption changes over time, as indicated by the dashed line in FIG.

[0070]

As is evident from the foregoing description, according to the first aspect of the present invention, by looking at the state of charge of the battery, at the start timing of the engine is determined, in each of the oxygen sensor and catalyst activation temperature or higher When the engine is started, the first energization start time and the second energization start time are shifted for a set time so that the oxygen sensor and the catalyst have the activation temperature at the time of the setting, and the charge of the battery of the hybrid vehicle is performed.
Inability to drive properly due to low engine starting
In addition, when the engine is started, unnecessary battery discharge due to cooling and reheating can be avoided, and the air-fuel ratio feedback can be performed while improving energy efficiency. It is possible to reduce the emission level of HC, CO, and the like in the exhaust gas at the time of starting the engine. Further, according to the invention of claim 2, in the start control device for a hybrid engine according to claim 1, the first heating means is particularly provided as an oxygen sensor temperature detection means for predicting the temperatures of the first heater and the oxygen sensor. When the second heating means functions as a catalyst temperature detecting means for predicting the temperature of the second heater and the catalyst, unnecessary battery discharge is avoided, and HC and CO in exhaust gas at the time of engine start are prevented. And other emission levels can be reduced.

Further, as another form of the first aspect , the first power supply start time and the second power supply start time are shifted by a set time so that the oxygen sensor and the catalyst are simultaneously activated at the time of starting the engine. In this case, unnecessary battery discharge due to cooling and reheating can be avoided, and the emission level of HC, CO, and the like in the exhaust gas at the time of starting the engine can be reduced. Further, as another two forms of the first aspect , in particular,
When the first energization control unit controls energization or non-energization of the first and second heating units, the air-fuel ratio feedback during the operation of the engine is enabled, and HC in the exhaust gas is activated by the activated catalyst. The emission level of CO and the like can be reduced.

Further, according to the third aspect of the present invention, the battery
By looking at the state of charge, at the start of the engine is predicted, when each of the oxygen sensor and catalyst to start the engine when the activation temperature or higher, a first prediction communication <br/> electric start timing The second predicted energization start time is shifted for a set time,
Oxygen sensor and catalyst is such that the activation temperature at the same time
The battery charge of the hybrid vehicle is
The engine cannot be started properly and the vehicle cannot run.
In addition, at the time of engine start, unnecessary battery discharge due to cooling and reheating can be avoided to improve energy efficiency and to enable air-fuel ratio feedback.
H in the exhaust gas at the start of the engine by the activated catalyst
The emission level of C, CO, etc. can be reduced. Further, according to the invention of claim 4, in the start control device for a hybrid engine according to claim 3, the first
When the heating means functions as oxygen sensor temperature detecting means for predicting the temperature of the first heater and the oxygen sensor, and the second heating means functions as catalyst temperature detecting means for predicting the temperature of the second heater and the catalyst, Unnecessary battery discharge can be avoided, and the emission level of HC, CO, and the like in exhaust gas at the time of engine start can be reduced.

Further, as another form of the third aspect, in particular, the first and second temperatures are determined based on the temperatures of the oxygen sensor and the catalyst so that the oxygen sensor and the catalyst are simultaneously activated.
If you set the respective first and second prediction energization start timing of the heating means, cooling, and avoiding unnecessary battery discharge due to reheating, H in the exhaust gas during engine start
The emission level of C, CO, etc. can be reduced. Furthermore, as another form of a two claims 3, in particular, to predict the start timing of the engine in accordance with a decrease in the rate of change of the charging rate, when the you start the engine, in the exhaust gas during engine start The emission level of HC, CO, etc. can be reduced.

In a third aspect of the present invention , the engine start timing is predicted based on the first and second power consumptions consumed by the first and second heating means until the engine start timing. , in the case of the you start the engine
Is cooled, to avoid unnecessary battery discharge due to reheating, HC in the exhaust gas at the start of the engine, it is possible to reduce the emission levels of CO and the like. Furthermore, another form of claim 3
As fourth state, in particular, as an oxygen sensor and catalyst during operation of the engine becomes the activation temperature range, respectively, was that controls the energization or non-energization of the first and second heating means situ
In this case, the air-fuel ratio feedback during the operation of the engine is enabled, and the activated catalyst can reduce the emission level of HC, CO, and the like in the exhaust gas.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a start control device for a hybrid engine as a first embodiment of the present invention.

FIG. 2 is a circuit diagram of a heater drive circuit for an O ₂ sensor used by the control device of FIG. 1;

FIG. 3 is a T _S characteristic diagram of a first heater used by the control device of FIG. 1;

FIG. 4 is a circuit diagram of a catalyst heater drive circuit used by the control device of FIG. 1;

FIG. 5 is a _TE characteristic diagram of a second heater used by the control device of FIG. 1;

[6] the control device of FIG. 1 represents the relationship between the accelerator pedal depression amount θa and the target vehicle speed V _T to be used in the running control subroutine is a characteristic diagram of the target vehicle speed V _T setting map.

FIG. 7 is a characteristic diagram of a vehicle acceleration α setting map, showing a relationship between a vehicle speed signal Vc and a vehicle acceleration α used by the control device of FIG. 1 in a travel control subroutine.

FIG. 8 is a graph showing a change over time in a battery charge rate used by the control device of FIG. 1;

FIG. 9 shows an activation temperature T _{E1 of a} catalyst used by the control device of FIG.
FIG. 4 is a characteristic diagram of a heating time t _E.

10 is a characteristic diagram of an activation temperature T _S1 -heating time t _{S of an} O ₂ sensor used by the control device of FIG. 1;

FIG. 11 shows the activation temperature T of the catalyst used by the control device of FIG.
_E1 - is t _E characteristic diagram heating time.

FIG. 12 is a characteristic diagram of an activation temperature T _S1 -heating time t _{S of an} O ₂ sensor used by the control device of FIG. 1;

FIG. 13 shows an activation temperature T of a catalyst used by the control device of FIG.
_E1 - is t _E characteristic diagram heating time.

14 is a characteristic diagram of an activation temperature T _S1 -heating time t _{S of an} O ₂ sensor used by the control device of FIG. 1; FIG. 2 is a characteristic diagram of an activation temperature T _E1 -heating time t _E used by the control device of FIG. 1.

FIG. 15 shows the activation temperature T of the catalyst used by the control device of FIG.
_{E It is a} time-dependent change diagram.

FIG. 16 is a graph showing an activation temperature T _S of the O ₂ sensor used by the control device of FIG. 1 over time.

FIG. 17 is a flowchart of a main routine used by the control unit of the control device in FIG. 1;

FIG. 18 is a flowchart of a temperature detection subroutine of an O ₂ sensor and a three-way catalyst used by a control unit of the control device in FIG. 1;

FIG. 19 is a flowchart of a travel control subroutine used by the control unit of the control device in FIG. 1;

FIG. 20 is a flowchart of a battery charging subroutine used by the control unit of the control device in FIG. 1;

FIG. 21 is a flowchart of a battery charging subroutine used by the control unit of the control device in FIG. 1;

FIG. 22 is a flowchart of a battery charging subroutine used by the control unit of the control device in FIG. 1;

FIG. 23 is a flowchart of a battery charging subroutine used by the control unit of the control device in FIG. 1;

FIG. 24 is a flowchart of a battery charging subroutine used by the control unit of the control device in FIG. 1;

FIG. 25 is a flowchart of a battery charging subroutine used by the control unit of the control device in FIG. 1;

FIG. 26 is a flowchart of an engine control routine used by the engine control unit of the control device of FIG. 1;

FIG. 27 is a characteristic diagram of a t _V time calculation map when the average difference value V _A = 1 is used by the control unit of the control device in FIG. 1;

FIG. 28 is a characteristic diagram of a t _V time calculation map for each average difference value V _A = 2 used by the control unit of the control device in FIG. 1;

FIG. 29 is a diagram illustrating the V used for calculating the power V _E consumed during the heating time t _E used by the control unit of the control device in FIG. 1;
It is a characteristic line diagram of an _E calculation map.

FIG. 30 is a diagram showing V used for calculating power V _E consumed during heating time t _S used by the control unit of the control device in FIG. 1;
FIG. 7 is a characteristic diagram of an _S calculation map.

FIG. 31 is a graph showing a transient characteristic curve of power consumption at a charging rate Vc ₀ used by the control unit of the control device in FIG. 1;

FIG. 32 is a flowchart of a battery charging subroutine used by the control unit of the control device in FIG. 1 in the second embodiment.

FIG. 33 is a flowchart of a battery charging subroutine used by the control unit of the control device in FIG. 1 in the second embodiment.

FIG. 34 is a flowchart of a battery charging subroutine used by the control unit of the control device in FIG. 1 in the second embodiment.

FIG. 35 is a flowchart of a battery charging subroutine used by the control unit of the control device in FIG. 1 in the second embodiment.

FIG. 36 is a flowchart of a time calculation subroutine until the control unit of the control device in FIG. 1 reaches the charging rate V1 used in the second embodiment.

FIG. 37 is a flowchart of a time calculation subroutine until a control unit of the control device in FIG. 1 reaches a charging rate V1 used in a modification of the second embodiment.

FIG. 38 is a time-dependent change diagram of the output during operation of the O ₂ sensor.

FIG. 39 is a time-dependent change diagram of the air-fuel ratio output that changes along with switching of the operating range of the engine.

[Explanation of symbols]

1 hybrid vehicle 2 motor 3 Battery 4 engine 5 generator 10 control unit 20 engine control unit 29 a catalytic converter 291 a three-way catalyst 292 the second heater 30 O ₂ sensor 301 first heater 34 Battery sensor A1 engine start timing determining unit A2 first Power supply control means A3 First engine start control means A4 Oxygen sensor temperature detection means A5 Catalyst temperature detection means T _S detection temperature T _E detection temperature T _S1 activation temperature T _E1 activation temperature R _S Resistance value of first heater R _E 2 the power V _E of the resistance value B1 engine starting time prediction unit B2 second energization control means B3 second engine start control means B4 O ₂ sensor temperature detector B5 catalyst temperature detecting means Vc charging ratio V _S first heater heater Power consumption of 2 heaters

──────────────────────────────────────────────────の Continuation of the front page (51) Int.Cl. ⁷ identification code FI F02N 17/02 F02N 17/02 D (58) Investigated field (Int.Cl. ⁷ , DB name) F02D 45/00 310 F01N 3 / 20 F02D 41/14 310

Claims (4)

(57) [Claims] 1. An electric motor for driving wheels of a vehicle, a battery for supplying electric power to the electric motor, an engine for driving a generator for supplying electric power to at least the battery, and oxygen provided in an exhaust passage of the engine. A sensor, first heating means for heating the oxygen sensor to an activation temperature and detecting the temperature of the oxygen sensor, a catalyst provided in the exhaust path, and heating the catalyst to an activation temperature and detecting the catalyst temperature A second heating means, a charge state detection means for detecting a charge state of the battery, an engine start time determination means for determining a start time of the engine according to an output of the charge state detection means, and an engine start time determination means. When it is determined that the engine is to be started, the first heating means or the second heating means based on the detected temperatures of the oxygen sensor and the catalyst. A first energization control means for starting energization to the other of the first heating means or the second heating means at a second energization start time after a set time has elapsed from a first energization start time to one of the stages; A first engine which starts the engine when it is determined by the timing determination means that the engine is to be started and the detected temperature of each of the oxygen sensor and the catalyst is equal to or higher than the activation temperature of each of the oxygen sensor and the catalyst.
A start control device for a hybrid engine, comprising: engine start control means. 2. The first heating means comprises a first heater for heating the oxygen sensor to an activation temperature, and an oxygen sensor temperature detecting means for predicting the temperature of the oxygen sensor from a resistance value of the first heater. The second heating means comprises a second heater for heating the catalyst to an activation temperature and a catalyst temperature detecting means for predicting the temperature of the catalyst from a resistance value of the second heater. Item 2. A start control device for a hybrid engine according to Item 1. 3. An electric motor for driving wheels of a vehicle, a battery for supplying electric power to the electric motor, an engine for driving a generator for supplying electric power to at least the battery, and oxygen provided in an exhaust passage of the engine. A sensor, first heating means for heating the oxygen sensor to an activation temperature and detecting the temperature of the oxygen sensor, a catalyst provided in the exhaust path, and heating the catalyst to an activation temperature and detecting the catalyst temperature A second heating means, a charge state detection means for detecting a charge state of the battery, an engine start time prediction means for predicting a start time of the engine at least according to an output of the charge state detection means, and at least the engine start time prediction The oxygen sensor and the catalyst such that the oxygen sensor and the catalyst are simultaneously at the activation temperature at the time predicted by the means. Second energization control means for controlling the first and second predicted energization start timings to the first and second heating means based on the respective detected temperatures, and the engine start timing is already determined by the engine start timing estimation means. A second engine start control means for starting the engine when the predicted temperature of each of the oxygen sensor and the catalyst is equal to or higher than the activation temperature of each of the oxygen sensor and the catalyst. Engine start control device. 4. The first heating means comprises a first heater for heating the oxygen sensor to an activation temperature, and an oxygen sensor temperature detecting means for predicting the temperature of the oxygen sensor from a resistance value of the first heater. The second heating means comprises a second heater for heating the catalyst to an activation temperature and a catalyst temperature detecting means for predicting the temperature of the catalyst from a resistance value of the second heater. Item 4. A start control device for a hybrid engine according to Item 3.