JP2000291457A - Hybrid vehicle control device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To prevent waste of power when an engine is stopped and to reduce the load on a control device. An E / G_ECU checks whether a fuel cut instruction has been received from an HEV_ECU (S101).
When the fuel cut instruction is received, the control power supply to the injector is turned off, the injector is deactivated, the fuel injection is stopped, and the fuel is cut (S10).
2) Further, the ignition power supply to the ignition coil is turned off, the igniter (not shown) is deactivated, and the ignition is cut (S103). As a result, unnecessary power consumption can be avoided when the engine is stopped, and the load on engine control can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control system for a hybrid vehicle using both an engine and a motor, and more particularly, to a control system for a hybrid vehicle which simultaneously performs an ignition cut at the time of fuel cut for stopping the engine.

[0002]

2. Description of the Related Art In recent years, hybrid vehicles that use both an engine and a motor have been developed for vehicles such as automobiles from the viewpoint of low pollution and resource saving. In this hybrid vehicle, the remaining capacity of the battery is insufficient. When the vehicle does not need to be charged and the vehicle is traveling at a low load where the required driving force is small, the engine is stopped and the traveling or the regenerative operation is performed only by the motor.

For example, Japanese Patent Application Laid-Open No. 8-79914 discloses that during regenerative braking of a hybrid vehicle, electric power generated by a motor is used for charging a battery, and when the battery voltage is equal to or higher than a set value, energy generated during regenerative braking is used. There is disclosed a technology for efficiently using regenerative energy by absorbing a part of the power by driving a generator having an engine as a load.

[0004]

However, in the conventional hybrid vehicle, when the engine is stopped for running only by the motor or for regenerative operation, the engine is stopped only by the fuel cut for stopping the supply of fuel. The idle ignition is performed in the normal control state.

As a result, wasteful electric power is wasted in the ignition when the engine is stopped. As a result, not only is the energy recovery efficiency reduced, but also the load on the control device for the ignition remains, and This is an obstacle to improving the overall controllability.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a control device for a hybrid vehicle which can prevent unnecessary power consumption and reduce the load on the control device when the engine is stopped. And

[0007]

In order to achieve the above object, an invention according to claim 1 is a first motor connected between an output shaft of an engine and a sun gear of a single pinion type planetary gear, and a first motor connected to the planetary gear. A second motor connected to the ring gear, a lock-up clutch for fastening and releasing the sun gear and the carrier of the planetary gear, and a second motor connected to the planetary gear carrier;
A control device for a hybrid vehicle including a power conversion mechanism that performs a speed change and a torque amplification between said planetary gears and drive wheels according to a speed ratio that can be switched in a plurality of stages or in a stepless manner, and supplies electric power to said motor. When the engine is stopped in accordance with the remaining capacity of the battery and the operating state of the vehicle, engine control means for executing an ignition cut together with a fuel cut is provided.

According to a second aspect of the present invention, in the first aspect of the invention, the engine control means includes a central control means for controlling a plurality of control systems of the hybrid vehicle and outputting a control command to each control system. When receiving a fuel cut instruction,
The ignition cut is executed together with the fuel cut.

That is, in the hybrid vehicle according to the first aspect of the present invention, when the engine is stopped by the engine control means, the ignition cut is executed together with the fuel cut, thereby preventing waste of power consumed by ignition when the engine is stopped. In addition, the calculation load of the ignition control is reduced.

According to the second aspect of the present invention, the engine is stopped when a fuel cut instruction is received from a central control unit that controls a plurality of control systems of the hybrid vehicle and outputs a control command to each control system. According to the fuel cut instruction, the fuel cut and the ignition cut are performed.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 relate to an embodiment of the present invention, FIG. 1 is a flowchart showing a control routine in an engine ECU, FIG. 2 is an explanatory diagram showing a configuration of a drive control system, and FIG. 3 is a control centering on HEV_ECU. FIG. 4 is an explanatory diagram showing a signal flow.

The hybrid vehicle according to the present invention is a vehicle that uses both an engine and a motor. As shown in FIG. 2, an engine 1 and a motor A (first motor) ) And Engine 1
A planetary gear unit 3 connected to the output shaft 1a of the motor B via a motor A, and a motor B (second motor) that controls the functions of the planetary gear unit 3 and serves as a driving force source at the time of starting and reversing and is responsible for recovery of deceleration energy. Motor)
And a power conversion mechanism 4 having a basic configuration and a power conversion mechanism 4 that performs a power conversion function during traveling by performing gear shifting and torque amplification.

Specifically, the planetary gear unit 3
A single pinion type planetary gear having a sun gear 3a, a carrier 3b rotatably supporting a pinion meshing with the sun gear 3a, and a ring gear 3c meshing with the pinion. The sun gear 3a is fastened to the carrier 3b.
A lock-up clutch 2 for disengaging is provided.

As the power conversion mechanism 4, a transmission combining a gear train, a transmission using a fluid torque converter, or the like can be used. The primary pulley 4b supported by the input shaft 4a and the transmission It is desirable to employ a belt-type continuously variable transmission (CVT) in which a drive belt 4e is wound around a secondary pulley 4d supported by the output shaft 4c. In the present embodiment, a power conversion mechanism will be described below. 4 will be described as CVT4.

That is, in the drive system of the hybrid vehicle according to the present invention, the planetary gear unit 3 having the lock-up clutch 2 interposed between the sun gear 3a and the carrier 3b includes the output shaft 1a of the engine 1 and the input shaft 4a of the CVT 4.
And the sun gear 3a of the planetary gear unit 3 is coupled to the output shaft 1a of the engine 1 via one motor A, and the carrier 3b is connected to the CVT 4
, And the other motor B is connected to the ring gear 3c. And the output shaft 4c of the CVT 4
A differential mechanism 6 is continuously provided through a reduction gear train 5, and a front or rear drive wheel 8 is continuously provided to the differential mechanism 6 via a drive shaft 7.

In this case, as described above, the engine 1 and the motor A are connected to the sun gear 3a of the planetary gear unit 3 and the motor B is connected to the ring gear 3c to obtain an output from the carrier 3b. Since the output is shifted and torque amplified by the CVT 4 and transmitted to the driving wheels 8, the two motors A and B can be used for both power generation and driving force supply, and a relatively small output motor Can be used.

The sun gear 3a of the planetary gear unit 3 is
And the carrier 3b, it is possible to form a drive shaft directly connected to the engine from the engine 1 to the CVT 4 in which the two motors A and B are disposed between the two motors A and B.
The driving force can be transmitted to the VT 4 or the braking force from the driving wheel 8 can be used.

The torque transmission of the engine 1 and the motors A and B via the planetary gear unit 3 when the lock-up clutch 2 is engaged and disengaged and the flow of electricity due to power generation are described in Japanese Patent Application No. Flat 10-4080
Issue.

The above-mentioned drive system is controlled by a control system (hybrid control system) for controlling the running of a hybrid vehicle in which seven electronic control units (ECUs) are connected by a multiplex communication system. Is composed of a microcomputer and a functional circuit controlled by the microcomputer.

Specifically, a hybrid ECU (HEV_ECU) for controlling the entire system as a central control means
A motor A controller 21 for driving and controlling the motor A, a motor B controller 22 for driving and controlling the motor B, an engine ECU (E / G_ECU) 23 for controlling the engine 1 as engine control means, a lock-up clutch 2, A transmission ECU (T / M_ECU) 24 for controlling the CVT 4 and a battery management unit (BA) for managing the power of the battery 10
T_MU) 25 on the first multiplex communication line 30
A brake E that is connected to the ECU 20 and performs brake control
CU (BRK_ECU) 26 is the second multiplex communication line 3
1 is connected to the HEV_ECU 20.

The HEV_ECU 20 controls the entire hybrid control system, and includes sensors and switches for detecting the driving operation status of the driver, for example, an accelerator pedal sensor (APS) 11 for detecting the amount of depression of an accelerator pedal (not shown). A brake switch 12 which is turned on by depressing a brake pedal (not shown);
An inhibitor switch 14 and the like, which are turned on when the operation position of the select mechanism 13 of the transmission is in the P range or the N range and turned off when the transmission is set in the D range, the R range, or the like, are connected.

The HEV_ECU 20 calculates the required vehicle drive torque based on the signals from the sensors and switches and the data transmitted from each ECU to determine the torque distribution of the drive system, as shown in FIG. Then, a control command is transmitted to each ECU by multiplex communication.

The HEV_ECU 20 has various indicators for indicating the operating state of the vehicle, such as the vehicle speed, the engine speed, the state of charge of the battery, etc., and a display 27 comprising a warning lamp for warning the driver when an abnormality occurs. Is connected. The indicator 27 is also connected to the T / M_ECU 24, and when an abnormality occurs in the HEV_ECU 20, the T / M_ECU 2 replaces the HEV_ECU 20.
4 performs an abnormal-time control, and displays an abnormality on the display 27.

On the other hand, the motor A controller 21 has an inverter for driving the motor A,
Basically, the constant rotation speed control of the motor A is performed by a servo ON / OFF command and a rotation speed command transmitted from the HEV_ECU 20 by multiplex communication. Further, the motor A controller 21 feeds back the torque, rotation speed, current value, and the like of the motor A to the HEV_ECU 20, and transmits data such as a torque limit request and a voltage value.

The motor B controller 22 includes an inverter for driving the motor B, and basically includes a servo ON / OFF (including normal rotation and reverse rotation) command and torque transmitted from the HEV_ECU 20 by multiplex communication. The constant torque control of the motor B is performed by a command (powering, regeneration). Also, HE from the motor B controller 22
The torque, the number of revolutions, the current value, and the like of the motor B are fed back and transmitted to the V_ECU 20, and data such as the voltage value is transmitted.

The E / G_ECU 23 basically controls the torque of the engine 1, and the HEV_ECU 20
And positive / negative torque commands, fuel cut commands, air-conditioner ON / OFF permission commands, and other control commands transmitted by multiplex communication, actual torque feedback data, vehicle speed, and shift select position (P, N) by the inhibitor switch 14.
Range, etc.), accelerator full-open data and accelerator full-close data by APS11 signal, brake switch 12 O
N, OFF state, a fuel injection amount from an injector (not shown) based on a brake operation state including ABS, E
Throttle opening by TC (electric throttle valve), A /
It controls power correction learning of auxiliary equipment such as C (air conditioner) and fuel cut.

In the E / G_ECU 23, HEV_
The ECU 20 issues a control torque value of the engine 1, a fuel cut, a full-open increase correction to the fuel injection amount,
The HEV_ECU sends the ON / OFF state of the air conditioner, data on the throttle valve fully closed by an idle switch (not shown), and the like.
20 and send it back to the engine 1
Is transmitted.

T / M_ECU 24 is provided by HEV_ECU 2
Control commands such as the target primary pulley rotation speed of the CVT 4 transmitted from 0, multiplex communication, a CVT input torque instruction, a lock-up request, etc., an E / G rotation speed, an accelerator opening, a shift select position by the inhibitor switch 14, a brake. Based on information such as the ON / OFF state of the switch 12, the air conditioner switching permission, the brake operation state including the ABS, and the data on the throttle valve fully closed of the engine 1 by the idle switch, the engagement / release of the lock-up clutch 2 is controlled and the CVT 4 Control the transmission gear ratio.

Further, the T / M_ECU 24 outputs the HEV
_ECU 20 for vehicle speed, input limiting torque, CVT4
The data of the primary pulley rotation speed and the secondary pulley rotation speed, the lockup completion, the shift state corresponding to the inhibitor switch 14 and the like are fed back and transmitted, and the E / G rotation speed increase request for increasing the oil amount of the CVT 4 is requested. , A low temperature start request or the like is transmitted.

The BAT_MU 25 is a so-called power management unit, and performs various controls for managing the battery 10, that is, charge / discharge control of the battery 10, fan control, external charge control, and the like.
Data such as voltage and current limit values and data indicating that external charging is being performed are transmitted to the HEV_ECU 20 by multiplex communication. When performing external charging, the contactor 9 is switched to disconnect the battery 10 from the motor A controller 21 and the motor B controller 22.

The BRK_ECU 26 is a HEV_ECU 2
A necessary braking force is calculated based on information such as a regenerable amount and regenerative torque feedback transmitted by multiplex communication from 0, and a hydraulic pressure of a brake system is controlled.
A regenerative amount command (torque command), a vehicle speed, a hydraulic pressure, a brake operation state including ABS and the like are fed back and transmitted to the HEV_ECU 20.

The driving modes of the hybrid vehicle controlled by the above-described hybrid control system can be roughly classified into the following three basic modes as viewed from the transmission input shaft. Is repeated. (1) Series (series & parallel) traveling mode When the required driving force is small, the lock-up clutch 2 is disengaged, and the engine 1 and the motor A travel mainly with the motor B while supporting the reaction force of the motor B. At this time, part of the driving force of the engine 1 is input to the sun gear 3a of the planetary gear unit 3, is combined with the driving force of the motor B of the ring gear 3c, and is output from the carrier 3b. (2) Parallel traveling mode When the required driving force is large, the lock-up clutch 2 is engaged to couple the sun gear 3a of the planetary gear unit 3 and the carrier 3b, and the driving force of the motor B from the ring gear 3c is applied to the driving force of the engine 1. The added value is output from the carrier 3b, and the vehicle travels using the torque of the engine 1 alone or both the engine 1 and the motor B. (3) Braking force regeneration mode In braking, the motor B regenerates braking force in coordination with the brake control. That is, the regenerative braking is performed by cooperatively sharing the braking torque corresponding to the depression amount of the brake pedal with the regenerative torque by the motor B and the braking torque by the brake mechanism.

In each of the above modes, in the low load series running mode in which the required driving force is small, if the remaining capacity of the battery 10 is sufficient, the running and the regenerative operation are performed using only the motors A and B. And during this time, H
The engine cut-off is instructed from the EV_ECU 20 to the E / G_ECU 23 to stop the engine 1.

That is, when the remaining capacity of the battery 10 falls below a specified value, the engine 1
Is driven as a generator, and travels while replenishing the power consumption of the battery 10 by driving the motor B. When the remaining capacity of the battery 10 is equal to or greater than a specified value and charging is not required, the motor A and the motor While driving with B,
At the time of regeneration, a driving force corresponding to the absorption torque of the motor A is generated in the motor B by the electric power generated by the motor A, and the battery 1
A braking force equivalent to engine braking is generated without charging to zero.

In the E / G_ECU 23, the HEV_ECU
When a fuel cut instruction is received from the engine 20, the engine 1 is stopped by the control routine of FIG. Hereinafter, E / G
A control routine in the _ECU 23 will be described.

In this control routine, first, at step S
At 101, it is checked whether a fuel cut instruction for stopping the engine has been received from the HEV_ECU 20. When the fuel cut instruction is received, the process proceeds from step S101 to step S102, in which the control power supply for the injector (not shown) is turned off, the injector is deactivated, the fuel injection is stopped, and the fuel cut is performed. Next, the process proceeds to step S103, in which the ignition power supply for the ignition coil (not shown) is turned off, the igniter (not shown) is deactivated, the ignition is cut off, and the routine exits.

That is, when the engine is stopped, the fuel cut and the ignition cut are performed, so that unnecessary power consumption can be avoided, the ignition control can be stopped, and the load on the engine control can be reduced.

When a fuel cut release instruction for driving the engine is received from the HEV_ECU 20, the flow advances from step S101 to step S104 to turn on the control power supply for the injector, return the injector to the operating state, and release the fuel cut. Restart fuel injection. Then, in step S105, the ignition power is turned on and the igniter is returned to the operating state to release the ignition cut, and ignition is started in accordance with the fuel injection timing.

[0039]

As described above, according to the present invention, when the engine of the hybrid vehicle is stopped, the ignition cut is executed together with the fuel cut, so that wasteful power consumed by ignition when the engine is stopped is prevented. At the same time, the burden on the ignition control can be reduced, and the energy utilization efficiency and the controllability of the entire system can be improved.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a control routine in an engine ECU.

FIG. 2 is an explanatory diagram showing a configuration of a drive control system.

FIG. 3 is an explanatory diagram showing a flow of a control signal centered on HEV_ECU.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Engine 2 ... Lock-up clutch 3 ... Planetary gear unit (single pinion type planetary gear) 3a ... Sun gear 3b ... Carrier 3c ... Ring gear 4 ... Belt type continuously variable transmission (power conversion mechanism) A ... 1st motor B ... 2nd Motor 20 HEV_ECU 23 E / G_ECU

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) F02D 43/00 301 F16H 3/72 A B60K 9/00 Z // F16H 3/72 F term (reference) 3G084 BA11 BA16 CA00 DA00 FA05 FA06 FA10 FA33 3G093 AA06 AA07 BA00 CA00 DA01 DA06 DB05 DB11 DB15 DB19 DB25 EA05 EA09 EA12 3J028 EA27 EB10 EB33 EB35 EB44 EB62 EB63 FB05 FB13 FC13 FC23 FC64 GA02 5H01 PU12 PU12 GA24 QN02 QN06 QN09 RB08 RE01 RE05 SE04 SE05 SE06 SE08 SJ12 SJ13 TB01 TE02 TI02 TI05 TI06 TO21 TO23 TO26 TR19 TZ07

Claims (2)

[Claims] A first motor connected between an output shaft of an engine and a sun gear of a single pinion type planetary gear, a second motor connected to a ring gear of the planetary gear, a sun gear of the planetary gear and a carrier are fastened. A lock-up clutch to be disengaged, and a power conversion mechanism that is connected to the planetary gear carrier and that performs a speed change and a torque amplification between the planetary gear and the drive wheels in accordance with a speed ratio that can be switched in a plurality of stages or steplessly. A control device for a hybrid vehicle, comprising: stopping the engine according to a remaining capacity of a battery that supplies power to the motor and an operating state of the vehicle.
A control device for a hybrid vehicle, comprising: engine control means for executing an ignition cut together with a fuel cut. 2. The engine control means, when receiving a fuel cut instruction from a central control means for controlling a plurality of control systems of the hybrid vehicle and outputting a control command to each control system, performs an ignition cut together with a fuel cut. The control device for a hybrid vehicle according to claim 1, wherein the control is executed.