JP2001206088A - Hybrid car controlling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure oil pressure required for controlling the speed change of a CVT by driving an engine driven oil pump even in the case where an engine stops while a hybrid car runs because of abnormality in a multiplex communication system comprising control units of a hybrid control system connected to each other. SOLUTION: In a transmission ECU24, the engagement and disengagement of a rock up clutch 2 are controlled based on the target primary pulley revolution of a CVT4, CVT input torque indication and rock up requirements, which are sent from a hybrid ECU2O via multiplex communication, and the speed change ratio of the CVT4 is also controlled. If an abnormality is caused by mixed noise in the multiplex communication system, the transmission ECU24 controls the behavior of the rock up clutch 2 for the hybrid ECU20 based on the car speed detected by a car speed sensor 16. Oil pressure that is required for controlling the speed change of the CVT4 is generated by driving the engine driven oil pump 15 by the reverse driving force from a driving wheels 8 by engaging the rock up clutch 2 while a hybrid car runs.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control apparatus for a hybrid vehicle in which a plurality of control units having different control targets are connected via a multiplex communication system.

[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. 2. Description of the Related Art A technology for improving the efficiency of power energy recovery and ensuring traveling performance by mounting two motors is often employed.

For example, Japanese Unexamined Patent Publication No. Hei 11-198668 discloses that when a required driving force is relatively small in accordance with a required driving force, a lock-up clutch is released and an engine drives a generator motor to generate electric power. In the case of a series driving mode in which the driving is mainly performed by a power source motor, if the required driving force is relatively large, a lock-up clutch is connected to drive the engine alone or the engine and the power source motor. A technology is disclosed in which a parallel running mode is selected in both cases, and the speed ratio of the transmission is hydraulically controlled using a hydraulic pressure generated by an oil pump connected to an output shaft of the engine as a source pressure. .

[0004] The running control of the hybrid vehicle in the prior art is performed by a hybrid control system in which each control unit is connected by a multiplex communication system. That is, a hybrid ECU that controls the entire system is mainly provided, and the hybrid ECU includes a power generation motor controller that drives and controls a power generation motor, a drive source motor controller that drives and controls a drive source motor, and an engine ECU that controls an engine. And a transmission ECU for controlling the lock-up clutch and the transmission.

[0005] For example, in a transmission ECU, a lock-up clutch from a hybrid ECU is connected.
Based on the release command and the shift command, the release and engagement of the lock-up clutch are controlled, and the shift control of the transmission is performed.

[0006]

However, when an abnormality such as noise mixing occurs in a multiplex communication system connecting the control units, the hybrid ECUs are used in the respective control units.
Required information cannot be input from the computer, and it becomes difficult to normally operate all functions such as the engine, the motor for generating electricity, the motor for driving power, and the transmission.

For this reason, if an abnormality occurs in the multiplex communication system during high-speed running and the engine stops, the oil pump driven by the engine also stops.
It becomes impossible to secure the hydraulic pressure required for the shift control of the transmission. For example, in a belt-type continuously variable transmission (CVT),
Belt slip is likely to occur.

In view of the above circumstances, the present invention makes it possible to secure a hydraulic pressure for controlling a transmission even if an abnormality occurs in a multiplex communication system connecting each control unit of a hybrid control system. It is an object to provide a control device for a hybrid vehicle.

[0009]

In order to achieve the above object, a control apparatus for a hybrid vehicle according to the present invention comprises an engine, a motor for a drive source, a transmission, a planetary gear unit, and a shift control system connected to an output shaft of the engine. An oil pump, wherein the first rotating element of the planetary gear unit is connected to the output shaft of the engine, and a second rotating element, which is a reaction force element, is connected to the drive source motor, and a third rotation Components are connected to the transmission, and the first rotating element and the second rotating element are freely connectable and disengageable via a lock-up clutch, and at least the engine, the driving motor, and the transmission And the operation of the lock-up clutch are controlled by a plurality of control units centered on a hybrid control unit, and the control units are connected by a multiplex communication system. The control unit for controlling the operation of the lock-up clutch controls the engagement or disengagement of the lock-up clutch based on the vehicle speed when an abnormality occurs in the multiplex communication system. I do.

In such a configuration, when the multiplex communication system is normal, each control unit coupled to the hybrid control unit via the multiplex communication system controls each control of the engine and the like based on information from the hybrid control unit. Control the target. When an abnormality occurs in the multiplex communication system, a control unit for controlling the operation of the lock-up clutch controls the engagement or release of the lock-up clutch based on the vehicle speed. As a result, even when the engine is stopped due to an abnormality in the multiplex communication system during high-speed running, the oil pump connected to the output shaft of the engine is rotated by the reverse driving force from the transmission side by the engagement of the lock-up clutch. Thus, it is possible to secure the hydraulic pressure required for the shift control of the transmission.

[0011] The control device for the second hybrid vehicle is a first hybrid vehicle.
In the hybrid vehicle control device, the control unit that controls the operation of the lock-up clutch determines whether or not the vehicle speed is immediately before stopping when an abnormality occurs in the multiplex communication system. The up-clutch is disengaged.

In such a configuration, since the lock-up clutch is released immediately before stopping, even if the vehicle is restarted after stopping, the vehicle does not start moving because the direct connection state by the lock-up clutch has already been released.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of a control system of a hybrid vehicle in which each control unit is connected by a multiplex communication system. FIG. 2 is a flowchart showing a lockup clutch control routine that is processed by a transmission ECU when an abnormality occurs in the multiplex communication system. FIG. 3 is an explanatory diagram showing the timing of switching between engagement and disengagement of the lock-up clutch.

The hybrid vehicle according to the present embodiment is
As shown in FIG. 1, the vehicle is a vehicle that uses both an engine and a motor. As shown in FIG. 1, an engine 1, a motor (power generation motor) A responsible for starting the engine 1 and generating / power assisting, and an output shaft 1a of the engine 1, A planetary gear unit 3 connected via a motor A as a power generation motor, and a motor (a power source power source) 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. And a belt-type continuously variable transmission (CVT) 4 that performs a power conversion function during traveling by performing gear shifting and torque amplification.

More specifically, the planetary gear unit 3
Sun gear 3a, which is a first rotating element, and sun gear 3a
Is a single pinion type planetary gear having a carrier 3b as a third rotating element rotatably supporting a pinion 3d meshing with the pinion 3d and a ring gear 3c as a second rotating element meshing with the pinion 3d, and a sun gear 3a and a ring gear 3c. And a lock-up clutch 2 for coupling and releasing the clutch. Reference numeral 15 denotes an oil pump for generating a shift control oil pressure, which is connected to the output shaft 1a of the engine 1 and is connected to the engine 1 (or the motor A).
Driven by

The CVT 4 is composed of a primary pulley 4b supported on the input shaft 4a, a secondary pulley 4d supported on the output shaft 4c, and a drive belt 4e wound between the two. I have.

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

Further, by connecting the sun gear 3a and the ring gear 3c of the planetary gear unit 3 by the lock-up clutch 2 in accordance with the running conditions, the two motors A and B are arranged between the engine 1 and the CVT 4. A drive shaft directly connected to the engine can be formed, and C
The driving force can be transmitted to the VT 4 or the reverse driving force from the driving wheel 8 can be used.

The above drive system has seven control units (E
The ECUs are controlled by a control system (hybrid control system) for controlling the running of a hybrid vehicle in which CUs are connected by a multiplex communication system, and each ECU comprises a microcomputer and a functional circuit controlled by the microcomputer. Have been. It is desirable to employ a communication network capable of coping with high-speed communication as a multiplex communication system for connecting the ECUs. For example, C is one of the ISO standard protocols as a vehicle communication network.
An AN (Controller Area Network) or the like can be adopted.

More specifically, a hybrid ECU (HEV_ECU) 20 for controlling the whole system is mainly used, and a motor A controller 21 for controlling the driving of the motor A, a motor B controller 22 for controlling the driving of the motor B, and the engine 1 are controlled. Engine ECU (E / G_ECU) 2
3, a transmission ECU (T / M_ECU) 24 for controlling the lock-up clutch 2 and the CVT 4, and a battery management unit (BAT_MU) 25 for managing the power of the battery 10 include a first multiplex communication line 3.
A brake ECU (BRK_ECU) 26 that is connected to the HEV_ECU 20 at 0 and performs brake control is connected to the HEV_ECU 20 via a second multiplex communication line 31.

The HEV_ECU 20 controls the entire hybrid control system, and includes sensors and switches for detecting a driving operation state of the driver, for example, an accelerator pedal sensor (APS) 11 for detecting a depression amount 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 a required vehicle drive torque based on signals from the respective sensors and switches and data transmitted from the respective ECUs to determine a torque distribution of the drive system. To send a control command.

The HEV_ECU 20 has various indicators for displaying 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 20 replaces the HEV_ECU 20.
24 performs an abnormal-time control, and displays an abnormality on the display 27.

For example, an abnormality occurs in the multiplex communication system due to noise mixing or the like, and the T / M_ECU 24
If the command to engage / disengage the lock-up clutch 2 output from the ECU 20 cannot be received, T / M_E
The CU 24 controls connection / disconnection of the lock-up clutch 2 based on the vehicle speed detected by the vehicle speed sensor 16.

That is, for example, when the engine 1 and the motor A are stopped due to an abnormality in the multiplex communication system during high-speed running, the oil pump 15 is not driven while the lock-up clutch 2 is kept open. , The control hydraulic pressure for the CVT 4 cannot be obtained, and the belt of the CVT 4 slips.
The lock-up clutch 2 is engaged by the _ECU 24, and the oil pump 15 is driven by the reverse driving force from the driving wheel 8, to secure the control oil pressure for the CVT 4 and to stop the vehicle safely.

When the vehicle stops, the driving wheels 8
Immediately before the vehicle stops, the lock-up clutch 2 is released in order to avoid a direct connection between the engine and the engine 1. As a result, even when the engine 1 is started normally due to the restart, the output of the engine 1 is not transmitted to the drive wheels 8 and the vehicle does not start running by mistake.

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. Also, the motor A controller 21 sends the motor A
The torque, rotation speed, current value, and the like are fed back and transmitted, and further, data such as a torque limit request and a voltage value are transmitted.

The motor B controller 22 includes an inverter for driving the motor B. Basically, a servo ON / OFF (including normal rotation and reverse rotation) command and torque transmitted from the HEV_ECU 20 by multiplex communication are provided. The constant torque control of the motor B is performed by a command (powering, regeneration). Also, the HEV is sent from the motor B controller 22.
_ECU 20 is fed back and transmits the torque, rotation speed, current value, and the like of motor B, and further transmits data such as a voltage value.

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_E
The HEV_ECU 2 transmits to the CU 20 the control torque value of the engine 1, execution of fuel cut, execution of full-open increase correction for the fuel injection amount, ON / OFF state of the air conditioner, throttle valve fully closed data by an idle switch (not shown), and the like.
In addition to transmitting the feedback to 0, a request for warming up the engine 1 and the like are 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. Each control valve in the hydraulic control circuit 28 is controlled 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, the throttle valve fully closed data of the engine 1 by the idle switch, and the like. It controls the engagement / disengagement of the lock-up clutch 2 and the gear ratio of the CVT 4.

From the T / M_ECU 24, HEV_
For the ECU 20, the vehicle speed, the input limiting torque, the primary pulley rotational speed and the secondary pulley rotational speed of the CVT 4,
Data such as the completion of lock-up, the shift state corresponding to the inhibitor switch 14, and the like are fed back and transmitted, and an E / G rotation speed increase request, a low-temperature start request, and the like for increasing the oil amount of the CVT 4 are 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 charging 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 provided by the 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 running mode of the hybrid vehicle controlled by the above-described hybrid control system is disclosed in Japanese Patent Application No. Hei 11-24456 previously filed by the present applicant, and therefore the description thereof is omitted here. .

In the hybrid control system according to the present embodiment, an abnormality is monitored via a multiplex communication system. When an abnormality occurs in the drive system or the control system, and when traveling is impossible, the vehicle is safely stopped. When the vehicle can run, the output of the drive system is limited to ensure the required minimum traveling performance.

The abnormality monitoring via the multiplex communication system is mainly performed by centrally managing the diagnosis result by the self-diagnosis function of each ECU by the HEV_ECU 20 which controls the system. The self-diagnosis function of each ECU includes diagnosis of disconnection and short-circuit occurrence by monitoring the output value of the sensor in addition to diagnosis of the ECU itself by the watchdog timer.
Checking of the consistency between the control data and the sensor output value, diagnosis of disconnection or short circuit occurrence of the actuator system based on the voltage applied to the actuator or the output current value, and the like are performed.

The self-diagnosis function of each ECU is described in Japanese Patent Application No. 10-32863 filed earlier by the present applicant.
No. 8, the description is omitted here.

In the HEV_ECU 20, when an abnormality is detected by self-diagnosis in each ECU and an abnormal notification is received by multiplex communication, when a regular communication from a predetermined ECU is not executed, or when each ECU is multiplexed,
If the control command transmitted to the CU and the control data fed back from each ECU do not match, for example,
Notifying other ECUs that the U is abnormal,
The operation of each ECU is restricted, and the occurrence of an abnormality is displayed on the display 27 to notify the driver of the occurrence of the failure.

As a multiplex communication system for connecting the ECUs,
It is desirable to employ a communication network capable of supporting high-speed communication. In the present embodiment, CAN, which is one of the ISO standard protocols, is used as a vehicle communication network.
(Controller Area Network).

As is well known, there are four types of CAN messages: a data frame of transmission data, a remote frame of a transmission request, an error frame when an error is detected, and an overload frame output when the reception side has not completed reception preparation. In the present embodiment, HEV_EC is used at the time of system startup and periodic system diagnosis using a remote frame.
U20 requests each ECU for a self-diagnosis result, and communicates control data such as a control command from HEV_ECU 20 to each ECU and feedback data from each ECU to HEV_ECU 20 using a data frame at regular time intervals. When the abnormality is detected by the self-diagnosis of HEV or the HEV_ECU 20, the abnormality notification of the random cycle is performed using the data frame.

In this case, each ECU sends HEV_ECU2
In a data frame transmitted at regular time intervals to 0, a counter for the number of transmissions irrespective of the control data is inserted into an empty area of the data field, and the value of the number of transmissions counter is monitored by the HEV_ECU 20, and the counter value is normally If the value is not incremented, it is determined that the abnormality is caused by noise in the multiplex communication system or the like, and the T / M
_ECU 24 is notified of abnormality and T / M_ECU 24 controls engagement / disengagement of lock-up clutch 2 based on the vehicle speed detected by vehicle speed sensor 16 instead of HEV_ECU 20.

The control of the lock-up clutch 2 executed by the T / M_ECU 24 is specifically performed according to the flowchart of FIG.

That is, first, at step S1, the vehicle speed V detected by the vehicle speed sensor 15 is read, and at step S2, H
The EV_ECU 20 checks whether or not the abnormal notification has been performed. If the abnormal notification has not been performed, the process directly exits the routine.

If an abnormal notification has been made, the flow advances to step S3 to check whether or not the current vehicle speed V is equal to or lower than the stop determination speed Vs.
Proceed to 4 to output a lock-up clutch engagement signal to the hydraulic control circuit 28 and exit the routine. On the other hand, immediately before the stop of V ≦ Vs, the process proceeds to step S5, where a lock-up clutch release signal is output to the hydraulic control circuit 28, and the routine exits.

As a result, as shown in FIG. 3, T / M_E
In the CU 24, the lock-up clutch 2 is released or engaged at the stop determination speed Vs. Note that the stop determination speed Vs is set to an extremely low speed of 10 km / h or less.

When the hydraulic control circuit 28 receives the lock-up clutch engagement signal from the T / M_ECU 24, the lock-up clutch 2 is engaged, and the drive wheels 8 are connected via the CVT 4 and the planetary gear unit 3 to the output shaft 1a of the engine 1.
And the oil pump 15 connected to the output shaft 1a is rotated by the reverse driving force from the driving wheel 8 to generate a control oil pressure for the CVT 4, thereby preventing the CVT 4 from slipping during traveling. Secure the hydraulic pressure required for shifting control.

Immediately before stopping, the hydraulic control circuit 28
Receives the lock-up clutch release signal from the T / M_ECU 24 and releases the lock-up clutch 2,
Since the ring gear 3c of the planetary gear unit 3 idles, the vehicle enters a neutral state, and after the vehicle stops,
When the ignition switch is turned off once and the ignition switch is turned on again to crank the engine 1 using the motor A as a starter, the multiplex communication system has returned to a normal state, and the engine 1 is started. Even in this case, since the planetary gear unit 3 is in the neutral state, the vehicle does not start moving.

[0050]

As described above, according to the present invention,
Even if an error occurs in the multiplex communication system that connects each control unit of the hybrid control system and it becomes impossible for each control unit to obtain information from the hybrid control unit, the operation of the lock-up clutch is performed. The control unit that controls the engagement and disengagement of the lock-up clutch based on the vehicle speed, so that even when the engine stops during high-speed running, the oil pump is driven by the reverse driving force from the transmission side. By driving, the hydraulic pressure required for the shift control of the transmission can be secured.

In this case, by releasing the lock-up clutch immediately before stopping the vehicle, the direct connection state by the lock-up clutch is released when the vehicle is restarted after the stop, so that the vehicle does not start at the time of starting.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a control system of a hybrid vehicle in which respective control units are connected by a multiplex communication system.

FIG. 2 is a flowchart showing a lock-up clutch control routine that is processed by a transmission ECU when an abnormality occurs in a multiplex communication system.

FIG. 3 is an explanatory diagram showing switching timing of engagement / disengagement of a lock-up clutch.

[Explanation of symbols]

 Reference Signs List 1 engine 1a output shaft 2 lock-up clutch 3 planetary gear unit 3a sun gear (first rotating element) 3b carrier (third rotating element) 3c ring gear (second rotating element) 4 belt-type continuously variable transmission 15 oil pump 16 Vehicle speed sensor 20 hybrid control unit 21, 22, 23 control unit 24 transmission control unit 30 multiplex communication line B drive source motor V vehicle speed

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) F02D 29/00 B60K 9/00 EF Term (Reference) 3D039 AA02 AA04 AB26 AD02 AD23 AD53 3D041 AA19 AA25 AA79 AB01 AC09 AC20 AE02 AE14 AE37 3G093 AA01 AA06 AA07 BA10 BA19 BA20 BA24 CA12 CB01 CB14 DB05 EB03 5H115 PA08 PC06 PG04 PI16 PI22 PI29 PI30 PO02 PO06 PO17 PU08 PU22 PU24 PU25 PV09 QA01 QA10 QE01 QE03 QE07 QE07 QE07 QE08 QE12 SE04 SE06 TB01 TE02 TI02 TI05 TI06 TO12 TO13 TO21 TO23 TO30 TZ07 UB05 UI13 UI23

Claims (2)

[Claims] An engine, a drive source motor, a transmission, a planetary gear unit, and a shift control oil pump connected to an output shaft of the engine, wherein a first rotating element of the planetary gear unit is used as an output of the engine. A second rotating element, which is a reaction force element, is connected to the drive source motor, a third rotating element is connected to the transmission, and the first rotating element and the second rotating element are connected to each other. A plurality of control units centering on a hybrid control unit for at least the operation of the engine, the drive motor, the transmission, and the lock-up clutch. In a hybrid vehicle control device in which the control units are connected by a multiplex communication system, when an abnormality occurs in the multiplex communication system , Hybrid vehicle control apparatus characterized by control unit for controlling the operation of the lock-up clutch for controlling the coupling or releasing of the lock-up clutch based on the vehicle speed. A control unit for controlling the operation of the lock-up clutch, when an abnormality occurs in the multiplex communication system, determines whether or not the vehicle speed is immediately before stopping; The control device for a hybrid vehicle according to claim 1, wherein the opening operation is performed.