JP2024010452A - Driving force control device for hybrid vehicle - Google Patents

Abstract

To provide a driving force control device for a hybrid vehicle capable of executing an OBD diagnosis at an operating point of a predetermined specified operating state and maintaining accuracy of abnormality detection of the OBD diagnosis to enable accurate diagnosis.SOLUTION: A driving force control device for a hybrid vehicle performs line trace control for controlling a value of a yaw rate that is a change rate of a yaw angle during turning to a target value. The hybrid vehicle includes a controller that controls an operating point of an operating state determined by engine torque and engine speed. The driving force control device for the hybrid vehicle includes: diagnosis request determination means for determining that a diagnosis of abnormality determination of an engine is requested; line trace control request means for determining satisfaction of a control request of the engine torque through the line trace control; and line trace control prohibition means for prohibiting the control of the engine torque through the line trace control when both of the diagnosis request determination means and the line trace control request means are satisfied.SELECTED DRAWING: Figure 2

Description

The present invention relates to a driving force control device for a hybrid vehicle equipped with an engine and a motor as driving force sources.

Patent Document 1 describes a vehicle driving force control device that can control the yaw rate, which is the rate of change of the yaw angle, without using a device that creates a difference between the torque applied to left and right drive wheels when the vehicle turns. has been done. According to the device described in Patent Document 1, a target value of the yaw rate is set when the vehicle turns, and a yaw moment amount that causes the yaw rate to reach the target value is calculated. The engine torque is then lowered based on the calculated yaw moment amount, and the motor compensates for the torque reduction by performing so-called line trace control, thereby preventing unintended vehicle behavior due to rolling and pitching that occurs when turning. It is believed that it can be suppressed.

Japanese Patent Application Publication No. 2021-133811

By the way, an in-vehicle fault diagnosis device called OBD (On-Board Diagnostics) is usually installed inside electronic control devices such as engines and transmissions, and when OBD diagnosis is executed, various sensors in the vehicle are It is possible to detect signal abnormalities, disconnections, and system failures.

In addition, OBD diagnosis is performed after the engine condition reaches a predetermined operating point determined by engine torque and engine speed, thereby improving the accuracy of abnormality detection in OBD diagnosis. is conventionally known. For example, when diagnosing catalyst deterioration or detecting abnormal failures in air-fuel ratio sensors, etc., the accuracy of detecting these abnormalities can be improved by increasing the amount of intake air in the engine to reach the operating point of a predetermined operating state. and can perform accurate OBD diagnosis.

However, when executing the OBD diagnosis, if the engine torque is reduced by the above-mentioned line trace control, it is difficult to reach the operating point of the predetermined operating state, and the OBD diagnosis is not accurately detected. There is a risk that the detection accuracy of diagnosis will decrease.

The present invention has been made by focusing on the above-mentioned technical problem, and it performs OBD diagnosis at a predetermined operating point of a predetermined operating state, maintains the accuracy of abnormality detection in OBD diagnosis, and performs accurate diagnosis. It is an object of the present invention to provide a driving force control device for a hybrid vehicle that is capable of controlling the driving force of a hybrid vehicle.

In order to achieve the above object, the present invention provides a line that controls the value of the yaw rate, which is the rate of change of the yaw angle during turning, to a predetermined target value in a hybrid vehicle that has an engine and a motor as a driving force source. A driving force control device for a vehicle equipped with trace control, wherein the hybrid vehicle includes a controller that controls an operating point of a driving state determined by engine torque and engine rotation speed, and the controller is configured to perform abnormality determination of the engine. diagnosis request determining means for determining that diagnosis of the engine torque is requested by the line trace control; line trace control requesting means for determining that the engine torque control request by the line trace control is satisfied; The present invention is characterized by comprising a line trace control prohibition means for prohibiting control of the engine torque by the line trace control when both the trace control request means and the trace control request means are satisfied.

According to this invention, when both the OBD diagnosis request determination means and the line trace control request means are established, the line trace control prohibition means prohibits control of engine torque by line trace control, thereby making it possible to perform OBD diagnosis. is performed at a predetermined operating point in a predetermined operating state, the accuracy of abnormality detection in OBD diagnosis can be maintained, and diagnosis can be made accurately.

Specifically, when executing OBD diagnosis, engine torque control such as engine torque reduction by line trace control is prohibited, so the operating point of the predetermined operating state required for abnormality detection accuracy of OBD diagnosis cannot be reached. , OBD diagnosis detection is performed accurately, and a decrease in detection accuracy of OBD diagnosis can be avoided.

FIG. 1 is a schematic diagram for explaining the configuration of an embodiment of the present invention. 1 is a flowchart for explaining a control example of a driving force control device for a hybrid vehicle in an embodiment of the present invention.

An example of a driving force control device for a hybrid vehicle according to an embodiment of the present invention will be described with reference to FIG. The vehicle Ve shown in FIG. 1 is driven by a power train 1, transmits the driving force from the power train 1 to an output shaft 2, and the output shaft 2 is connected to rear left and right drive wheels 4 via a differential gear unit 3. It is a so-called FR (front engine, rear drive) type vehicle.

Here, the power train 1 may have a conventionally known configuration for hybrid vehicles, and includes, for example, an engine 5 and a generator 6 as driving power sources, and a transmission 7, a torque converter (not shown), etc. The structure may include a power transmission mechanism.

An electronic control unit (hereinafter referred to as ECU) 8 for controlling the power train 1 described above is provided. This ECU 8 corresponds to the "controller" in the embodiment of the present invention, and is mainly composed of a microcomputer, similar to conventionally known electronic control devices, and controls various functions installed in the vehicle Ve. A signal is input from the sensor, and a command signal is output to actuators such as the engine 5 and motor 6 in the power train 1 based on the input signal and a pre-stored calculation formula, map, or control flow. . Note that the ECU 8 may be configured by individual ECUs that control the engine 5, motor 6, transmission 7, etc., respectively.

Examples of signals input to the ECU 8 include a signal from a sensor that detects the rotational speed of the engine 5, a signal from an accelerator opening sensor that detects the operation amount of an accelerator pedal (not shown), and the like. Further, the map stored in the ECU 8 includes a driving force map for determining the driving force required of the vehicle Ve based on the accelerator opening degree and the vehicle speed.

The ECU 8 includes at least a diagnostic request determination means 9, a line trace control request means 10, and a line trace control prohibition means 11 as a functional configuration.

The diagnostic request determining means 9 has a function of determining whether or not there is a request to increase the intake air amount of the engine 5 in conjunction with execution of OBD diagnosis for diagnosing abnormality of the engine 5. After detecting the start of execution of the OBD diagnosis, the state of the engine 5 is brought to the operating point of a predetermined operating state predetermined by the engine torque and engine rotation speed in conjunction with the OBD diagnosis. It is determined whether there is a request to increase the intake air amount of the engine 5 in order to reach that operating point. Here, the intake air amount is detected based on, for example, the engine speed and the accelerator opening, and the required intake air amount is calculated from the detected intake air amount.

The line trace control requesting means 10 has a function of determining whether there is a request to control engine torque by line trace control. After detecting the start of execution of line trace control, it is determined whether or not there is a request for torque control, such as reducing engine torque, in conjunction with line trace control.

The line trace control prohibition means 11 has a function of prohibiting engine torque control by line trace control when both the diagnosis request determination means 9 and the line trace control request means 10 are satisfied.

FIG. 2 is a flowchart showing an example of control of the driving force control device for a hybrid vehicle in an embodiment of the present invention. In the example shown in FIG. 2, first, it is determined whether there is a request to increase the amount of intake air (step S1). Here, the diagnosis request determining means 9 determines whether there is a request to increase the amount of intake air. If there is no request to increase the amount of intake air, that is, if the determination in step S1 is negative, this routine is temporarily terminated without performing any particular control.

On the contrary, if there is a request to increase the amount of intake air, that is, if it is determined affirmatively in step S1, it is determined whether there is a request to control the engine torque by line trace control (step S2). . Here, the presence or absence of a request to control the engine torque by line trace control is determined by the line trace control requesting means 10. If there is no request to control the engine torque by line trace control, that is, if the determination in step S2 is negative, this routine is temporarily terminated without performing any particular control.

On the contrary, if there is a request to control the engine torque by line trace control, that is, if the determination in step S2 is affirmative, line trace control is prohibited (step S3). That is, if both the diagnosis request determination means 9 and the line trace control request means 10 are satisfied, the line trace control prohibition means 11 prohibits engine torque control by line trace control.

According to this invention, when both the OBD-based diagnosis request determination means 9 and the line trace control request means 10 are established, the line trace control prohibition means 11 prohibits engine torque control by line trace control. , OBD diagnosis is executed at a predetermined operating point of a predetermined operating state, and the accuracy of abnormality detection of OBD diagnosis can be maintained and accurate diagnosis can be performed. Specifically, when executing OBD diagnosis, engine torque control such as engine torque reduction by line trace control is prohibited, so it is impossible to reach the operating point of the predetermined operating state required for abnormality detection accuracy of OBD diagnosis. , OBD diagnosis detection is performed accurately, and a decrease in detection accuracy of OBD diagnosis can be avoided.

Note that this invention is not limited to the embodiments described above, and can be implemented with appropriate modifications within the scope of the objective of this invention. Furthermore, the present invention is not limited to the configuration of the flowchart described above. For example, the order of step S1 and step S2 may be changed, and although step S1 is set to increase the amount of intake air, the invention is not limited to this. Requirements can be changed.

Further, although an FR type vehicle is cited as an example of the present invention, the present invention is not limited to this, and the same operation and effect can be achieved regardless of whether the vehicle is attached to the power train 1 or the drive wheels 4 in the front or rear direction. Can be done.

1 Powertrain 2 Output shaft 3 Differential gear unit 4 Drive wheel 5 Engine 6 Motor 7 Transmission 8 ECU
9 Diagnosis request determination means 10 Line trace control request means 11 Line trace control prohibition means Ve Vehicle

Claims (1)

A driving force control device for a hybrid vehicle equipped with line trace control that controls a yaw rate value, which is the rate of change of the yaw angle during turning, to a predetermined target value in a hybrid vehicle that has an engine and a motor as a driving power source. There it is,
The hybrid vehicle includes a controller that controls an operating point of a driving state determined by engine torque and engine rotation speed,
The controller includes:
Diagnosis request determining means for determining that a diagnosis for abnormality determination of the engine is requested; line trace control requesting means for determining that the request for controlling the engine torque by the line trace control is satisfied; and the diagnostic request. Driving a hybrid vehicle characterized by comprising: line trace control prohibition means for prohibiting control of the engine torque by the line trace control when both the determination means and the line trace control request means are established. Force control device.

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