KR20160133998A - Apparatus and method for learning engine friction torque for vehicle - Google Patents

Abstract

The present invention relates to a device for learning engine friction torque of a vehicle and, specifically, to a device and a method for learning engine friction torque of a vehicle, which learn engine friction torque using motor charging torque in a battery charging mode while the vehicle stops. To achieve the same, according to an embodiment of the present invention, the device for learning engine friction torque of the vehicle includes: an engine and a driving motor which are a power source; an engine controller controlling the engine by detecting an operation state of the engine; a motor controller controlling driving and the torque of the driving motor; and a vehicle controller integrally controlling the engine controller and the motor controller via a network in accordance with a vehicle state. The vehicle controller includes: a state determining unit determining whether the engine has a part load and whether the vehicle is in a battery charging mode and stops based on the vehicle state; a deviation calculation unit calculating an engine friction torque deviation based on engine output torque and motor charging torque; and a torque learning unit learning the engine friction torque based on the engine friction torque deviation.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an apparatus and method for learning an engine friction torque of a vehicle,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine friction torque learning apparatus for a vehicle, and more particularly, to an apparatus and method for learning an engine friction torque of a vehicle using a motor charging torque in a battery charging mode during stopping of a vehicle.

The use of pollution-free energy is becoming increasingly important as the environmental pollution problem of the earth becomes serious every day. Especially, the problem of air pollution in big cities is becoming serious day by day, and automobile exhaust gas is one of the main causes.

Environment-friendly vehicles including hybrid vehicles, electric vehicles, and the like have been developed and operated in order to solve problems related to exhaust gas and provide fuel economy improvement.

Generally, a hybrid vehicle means that two or more different kinds of power sources are efficiently combined to drive the vehicle. However, in most cases, this means a vehicle driven by an engine that obtains a rotational force by burning fuel and a motor that obtains a rotational force by battery power.

Such hybrid vehicles are being studied more actively in response to the demand for the improvement of fuel efficiency and development of environmentally friendly products as vehicles that not only use engines but also electric motors as auxiliary power sources to reduce battery and improve fuel efficiency .

The hybrid vehicle uses an electric vehicle (EV) mode, an electric vehicle mode, an HEV (Hybrid Electric Vehicle) mode, which uses the rotational power of the engine as the main power and serves as an auxiliary power for the motor, And a regenerative braking mode in which energy is recovered and charged to the battery by generating the motor with braking and inertia energy while driving.

In this way, the hybrid vehicle uses both the mechanical energy of the engine and the electric energy of the battery, utilizes the optimal operating range of the engine and the motor, and recovers energy from the motor during braking, thereby improving fuel efficiency and utilizing energy efficiently.

Generally, gasoline vehicles proceed to learn the engine friction torque during engine idling during stopping. However, the hybrid vehicle was unable to learn the engine friction torque when the engine stopped at a stop. Therefore, the hybrid vehicle can not learn the engine friction torque, so the accuracy of the engine torque is lowered.

The matters described in the background section are intended to enhance the understanding of the background of the invention and may include matters not previously known to those skilled in the art.

An embodiment of the present invention provides an apparatus and method for learning an engine friction torque of a vehicle that learns an engine friction torque using a motor charging torque in a battery charging mode during stopping of a vehicle.

An embodiment of the present invention provides an apparatus and method for learning an engine friction torque of a vehicle capable of learning an engine friction torque during part load operation of an engine in a battery charging mode during a stop.

In an embodiment of the present invention, an engine and a drive motor, which are power sources, An engine controller for detecting the operating state of the engine and controlling the engine; A motor controller for controlling driving and torque of the driving motor; And a vehicle controller for integrally controlling the engine controller and the motor controller via a network according to the vehicle condition, wherein the vehicle controller is in a stopped state based on the vehicle condition, part; A deviation arithmetic unit for calculating an engine friction torque deviation based on an engine output torque and a motor charging torque; And a torque learning unit that learns an engine friction torque based on the engine friction torque deviation.

Further, the vehicle controller may further include: a torque calculation unit for calculating the engine output torque based on a target charging torque and an engine friction setting torque; And a torque detector for detecting the motor charge torque by driving the drive motor based on the engine speed and the engine target speed.

The deviation arithmetic unit may calculate an engine friction drive torque according to the engine output torque and the motor charge torque, and calculate the engine friction torque deviation based on the engine friction drive torque and the engine friction set torque.

Further, the torque learning unit may learn the engine friction torque based on the engine friction setting torque and the engine friction torque deviation.

According to another embodiment of the present invention, there is provided a method for controlling a vehicle, comprising: determining whether a vehicle state satisfies a torque learning entry condition; Calculating an engine output torque when the vehicle condition meets a torque learning entry condition; Detecting a motor charge torque based on an engine speed and an engine target speed; Calculating an engine friction torque deviation based on the engine output torque and the motor charging torque; And learning the engine friction torque based on the engine friction torque deviation.

According to another embodiment of the present invention, the method further comprises: determining whether the vehicle is in a stopped state or in a battery charging mode; Determining whether the engine is in a part load state when the vehicle is in a stopped state and in a battery charging mode; Calculating an engine output torque based on a target charging torque and an engine friction setting torque when the engine is in a part load state; Controlling a motor speed based on an engine target speed and an engine speed to detect a motor charging torque; Calculating an engine friction torque deviation based on the motor impact torque and the motor charging torque; And a step of updating the engine friction torque based on the engine friction torque deviation to perform learning of the engine friction torque.

The embodiment of the present invention can improve the fuel efficiency because it can follow the optimum efficiency operating point of the engine by learning the engine friction torque based on the motor charging torque in the battery charging mode during the stop of the vehicle and outputting the accurate engine torque .

Further, the embodiment of the present invention can improve the accuracy of the engine torque, so that the vehicle shock can be reduced in the shift and other transition periods.

In addition, effects obtainable or predicted by the embodiments of the present invention will be directly or implicitly disclosed in the detailed description of the embodiments of the present invention. That is, various effects to be predicted according to the embodiment of the present invention will be disclosed in the detailed description to be described later.

1 is a view schematically showing an apparatus for learning an engine friction torque of a vehicle according to an embodiment of the present invention.
2 is a block diagram schematically showing a vehicle controller of an engine friction torque learning apparatus of a vehicle according to an embodiment of the present invention.
3 is a flowchart showing a method of learning an engine friction torque of a vehicle according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an operation principle of an embodiment of an apparatus and method for learning an engine friction torque of a vehicle according to the present invention will be described in detail with reference to the accompanying drawings and description. It should be understood, however, that the drawings and the following detailed description are exemplary and explanatory of various embodiments for effectively illustrating the features of the present invention. Therefore, the present invention should not be limited to the following drawings and descriptions.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. The terms used below are defined in consideration of the functions of the present invention, which may vary depending on the user, intention or custom of the operator. Therefore, the definition should be based on the contents throughout the present invention.

In order to efficiently explain the essential technical features of the present invention, the following embodiments will appropriately modify, integrate, or separate terms to be understood by those skilled in the art to which the present invention belongs , And the present invention is by no means thereby limited.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a view schematically showing an apparatus for learning an engine friction torque of a vehicle according to an embodiment of the present invention.

1, an engine friction torque learning apparatus (hereinafter referred to as an "engine friction torque learning apparatus") 100 of a vehicle includes a state detector 50, an engine 110, an engine clutch 120, a drive motor 130 A battery 140, a transmission 150, an engine control unit (hereinafter referred to as ECU) 160, a motor control unit (MCU) 170, a transmission controller A Traction Control System (TCS) 190, and a Hybrid Control Unit (HCU) 180 are collectively referred to as a TCU (Transmission Control Unit) 200).

The state detector 50 detects the vehicle state. That is, the state detector 50 detects the overall vehicle condition including the vehicle speed, the speed change stage, the displacement of the accelerator pedal, the displacement of the brake pedal, and the like in the operation of the hybrid vehicle. The status detector 50 provides the HCU 200 with the detected vehicle status.

The thrust is controlled by the engine 160 under the control of the ECU 160, and the driving of the engine 110 is controlled to the optimum operating point under the control of the ECU 160. [

The engine clutch 120 is disposed between the engine 110 and the drive motor 130 and is operated under the control of the HCU 200 to intercept power transmission between the engine 110 and the drive motor 130. That is, the engine clutch 120 connects or disconnects the power between the engine 110 and the drive motor 130 in accordance with the switching between the EV (Electric Vehicle) mode and the HEV (Hybrid Electric Vehicle) mode.

When the engine clutch 120 is open, the hybrid vehicle is driven only by the drive motor 130, so that the hybrid vehicle is driven by the drive motor 130. When the engine clutch 120 is locked, Or may be driven by the engine 110 and the drive motor 130 only.

The driving motor 130 is operated by the three-phase AC voltage applied from the MCU 170 to generate torque. The drive motor 130 is operated as a generator during the other running or regenerative braking to supply a voltage to the battery 140.

The battery 140 is composed of a plurality of unit cells, and a high voltage for providing a driving voltage to the driving motor 130 is stored. The battery 140 supplies the drive voltage to the drive motor 130 in the EV mode or the HEV mode and is charged with the voltage generated by the motor during the regenerative braking.

The battery 140 may be charged by the voltage and current supplied through the charging device when the commercial power source is plugged in.

The transmission 150 adjusts the transmission ratio under the control of the TCU 180 and distributes the applied output torque through the engine clutch 120 to the drive wheels according to the operation mode to deliver the output torque to the drive wheels to drive the hybrid vehicle .

The ECU 160 is connected to the HCU 200 via a network and is interlocked with the HCU 200 to control the engine operation state such as the driver's required torque signal, cooling water temperature, engine speed, throttle valve opening, And controls the overall operation of the engine 110 according to the operation of the engine 110. The ECU 160 provides the operating state of the engine 110 to the HCU 200.

The MCU 170 controls driving and torque of the driving motor 130 under the control of the HCU 200 and stores the voltage generated by the driving motor 130 in the battery 140 during the regenerative braking.

The TCU 180 controls the overall operation of the transmission 150 by controlling the speed ratio according to the output torque of the ECU 160 and the MCU 170 and determining the regenerative braking amount. The TCU 180 provides the operating state of the transmission 150 to the HCU 200.

The TCS 190 is a safety system that controls the driving force of the hybrid vehicle so that excessive driving force is generated at the time of starting or accelerating on an eye, an ice sheet, or an asymmetric road surface so that the tire does not slip.

The TCU 180 and the TCS 190 cooperate with each other to control the output torque of the engine 110 by adjusting the fuel injection amount, the ignition timing, the throttle valve and the like. The output torque of the drive motor 130 Can be controlled simultaneously.

The HCU 200 is a top-level controller for setting the hybrid traveling mode and controlling the overall operation of the hybrid vehicle. The HCU 200 integrally controls the lower controllers connected through the network, collects and analyzes the information of each lower controller, and executes coordination control to control the output torque of the engine and the driving motor 130.

The HCU 200 determines whether the engine frictional torque entry condition is satisfied based on the vehicle condition received from the lower controller. The HCU 200 calculates the engine friction torque deviation based on the engine output torque and the motor charging torque and learns the engine friction torque based on the engine friction torque deviation when the vehicle condition satisfies the engine frictional torque entry condition.

The HCU 200 will be described in more detail with reference to FIG.

The conventional operation of the hybrid vehicle according to the present invention including the above-described functions is the same as or similar to that of the conventional hybrid vehicle, so a detailed description thereof will be omitted.

2 is a block diagram schematically showing a vehicle controller of an engine friction torque learning apparatus 100 of a vehicle according to an embodiment of the present invention.

2, the HCU 200 includes a communication unit 210, a state determination unit 220, a torque calculation unit 230, a torque detection unit 240, a deviation calculation unit 250, a torque learning unit 260, 270 and a storage unit 280.

The communication unit 210 is connected to the controllers of the engine friction torque learning apparatus 100 to receive data from the controllers and transmit data to the controllers. That is, the communication unit 210 is connected to the lower controllers through a CAN (Controller Area Network) communication network, and receives the vehicle status for controlling the hybrid vehicle. In addition, the communication unit 210 can receive the operating state of the engine 110 from the ECU 160. [

The state determination unit 220 determines whether the engine frictional torque entry condition is satisfied based on the vehicle state received from the communication unit 210. In other words, the state determination unit 220 determines whether the hybrid vehicle is stopped and the battery 140 is being charged based on the vehicle state. At this time, the state determination unit 220 can determine whether the vehicle is stopped through the vehicle speed included in the vehicle state, the opening of the accelerator pedal, the opening of the brake pedal, the operation state of the motor, and the like.

The state determination unit 220 determines whether the engine 110 is in the part load state based on the vehicle state. That is, the state determination unit 220 can determine whether the engine 110 is in the part load state based on the engine speed, the throttle opening, the intake amount, and the oxygen amount included in the operation state of the engine 110.

The torque calculation unit 230 calculates the engine output torque when the vehicle state is the engine friction torque entry condition in the state determination unit 220. [ That is, the torque calculating unit 230 calculates the engine output torque based on the target charging torque and the engine friction setting torque when the vehicle condition is the engine friction torque entry condition. The target charging torque indicates the target torque of the driving motor 130 for charging the battery 140 when the vehicle stops, and the engine friction setting torque indicates an engine friction torque preset in accordance with the specifications of the engine 110 . The target charging torque and the engine friction setting torque may be set by an administrator or by a predetermined algorithm (e.g., a program or a probabilistic model).

The torque detection unit 240 detects the motor charging torque. That is, the torque detector 240 drives the driving motor 130 based on the engine speed and the engine target speed. At this time, the torque detector 240 can drive the driving motor through the MCU 170. [

The deviation calculator 250 calculates the engine friction torque deviation based on the engine output torque and the motor charging torque. That is, the deviation arithmetic unit 250 calculates the engine friction drive torque based on the engine output torque and the motor charge torque to confirm the deviation between the set engine friction torque and the engine friction torque obtained by driving the actual vehicle, And the engine friction set torque. At this time, the engine friction drive torque may indicate the engine friction torque used when the engine 110 is actually driven.

The torque learning unit 260 learns the engine friction torque based on the engine friction torque deviation. That is, the torque learning unit 260

The control unit 270 includes a communication unit 210, a status determination unit 220, a torque calculation unit 230, a torque detection unit 240, a deviation calculation unit 250, a torque learning unit 260, And controls the storage unit 280 to learn the engine friction torque.

The storage unit 280 stores data required by the components of the HCU 200 and data generated by the HCU 200. For example, the storage unit 280 stores the state of the vehicle received through the communication unit 210, and may store the determination result determined by the state determination unit 220. The storage unit 280 stores the engine friction torque and updates and stores the engine friction torque when learning is performed by the torque learning unit 260.

In addition, the storage unit 280 stores various programs for controlling the overall operation of the engine friction torque device.

The storage unit 280 includes a communication unit 210, a status determination unit 220, a torque calculation unit 230, a torque detection unit 240, a deviation calculation unit 250, a torque learning unit 260, You can provide the necessary data on request. The storage unit 280 may be an integrated memory or may be subdivided into a plurality of memories. For example, the storage unit 280 may be a read only memory (ROM), a random access memory (RAM), a flash memory, or the like.

Hereinafter, a method of learning engine friction torque of a vehicle according to an embodiment of the present invention will be described.

3 is a flowchart showing a method of learning an engine friction torque of a vehicle according to an embodiment of the present invention. The controllers of the engine friction torque learning apparatus 100 of the vehicle according to an embodiment of the present invention described above with reference to FIGS. 1 and 2 can be integrated or subdivided, Functions can be configured as an apparatus for learning an engine friction torque of a vehicle 100 according to an embodiment of the present invention. Therefore, in describing the method of learning the engine friction torque of the engine friction torque learning apparatus 100 of a vehicle according to an embodiment of the present invention, the main body of each step is not the controllers but the engine friction torque learning apparatus (100) will be mainly described.

Referring to FIG. 3, the engine friction torque learning apparatus 100 confirms the vehicle condition (S310). In other words, the engine friction torque learning apparatus 100 includes the vehicle speed, the speed change stage, the displacement of the accelerator pedal, the displacement of the brake pedal, the cooling water temperature, the engine speed, the throttle valve opening, the intake air amount, Check the vehicle condition.

The engine friction torque learning apparatus 100 determines whether the vehicle is in a stop state based on the vehicle state and is in the charging mode of the battery 140 (S320).

On the other hand, the engine friction torque learning apparatus 100 stops the engine friction torque learning if the vehicle state is not stopped or the battery 140 is not in the charging mode.

The engine friction torque learning apparatus 100 determines whether the engine 110 is a part load if the vehicle state is stopped and the battery 140 is being charged (S330). That is, the engine friction torque learning apparatus 100 can determine whether the engine 110 is a part load based on the cooling water temperature, the engine speed, the throttle valve opening, the intake air amount, the oxygen amount, etc. included in the vehicle state.

On the other hand, the engine friction torque learning apparatus 100 stops learning the engine friction torque if the engine 110 is not a part load, based on the vehicle condition.

The engine friction torque learning device 100 calculates the engine output torque based on the target charging torque and the engine friction setting torque (S340). In other words, the engine friction torque learning apparatus 100 confirms the preset target charging torque and the engine friction setting torque, and calculates the engine output torque using the target charging torque and the engine friction setting torque. That is, the engine friction torque learning apparatus 100 can calculate the engine output torque using the following equation (1).

[Equation 1]

Engine output torque = Target charge torque + Engine friction setting torque

The engine friction torque learning device 100 detects the motor charging torque (S350). In other words, the engine friction torque learning apparatus 100 confirms the motor torque based on the engine speed and the engine target speed. The engine friction torque learning apparatus 100 controls the speed of the drive motor 130 based on the motor torque to detect the motor charge torque which is the torque output from the drive motor 130. [

The engine friction torque learning apparatus 100 calculates an engine friction torque deviation (S360). In other words, the engine friction torque learning apparatus 100 calculates the engine friction drive torque based on the engine output torque calculated in step S340 and the motor charge torque in step S350. That is, the engine friction torque learning apparatus 100 can calculate the engine friction drive torque using the equation (2).

&Quot; (2) "

Engine friction drive torque = Engine output torque - Motor charge torque

Then, the engine friction torque learning apparatus 100 calculates the engine friction torque deviation based on the engine friction drive torque and the engine friction set torque. That is, the engine friction torque learning apparatus 100 can calculate the engine friction torque deviation through the following equation (3).

&Quot; (3) "

Engine Friction Torque Deviation = Engine Friction Drive Torque - Engine Friction Set Torque

The engine friction torque learning apparatus 100 learns the engine friction torque based on the engine friction torque deviation (S370). Specifically, the engine friction torque learning apparatus 100 calculates the engine friction calculation torque based on the engine friction setting torque and the engine friction torque deviation. That is, the engine friction torque learning apparatus 100 can calculate the engine friction calculation torque through the following equation (4).

&Quot; (4) "

Engine friction calculation torque = engine friction setting torque + engine friction torque variation

The engine friction torque learning apparatus 100 updates the engine friction calculation torque with the engine friction torque and stores the updated engine friction torque. On the other hand, when the first vehicle is operated, the engine friction torque may be stored at the initial set engine friction torque, and after the running, the engine friction torque may be stored after performing S370 at step S310. Further, the engine friction setting torque after the running is progressed may be the calculated engine friction torque that performed the S370 to S310.

Accordingly, the engine friction learning apparatus of the vehicle according to the embodiment of the present invention learns the engine friction torque based on the motor charging torque in the battery charging mode during the stopping of the vehicle and outputs the accurate engine torque, Fuel ratio can be improved.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the appended claims. It will be understood that the invention may be varied and varied without departing from the scope of the invention.

50: state detector
100: an engine friction torque learning device of a vehicle
110: engine
130: motor
140: Battery
150: Transmission
160: ECU
170: MCU
180: TCU
190: TCS
200: HCU

Claims (13)

An engine and a drive motor which are power sources;
An engine controller for detecting the operating state of the engine and controlling the engine;
A motor controller for controlling driving and torque of the driving motor; And
A vehicle controller for integrally controlling the engine controller and the motor controller via a network according to the vehicle condition;
, ≪ / RTI &
The vehicle controller
A state determining unit for determining whether the engine is a part load and is in a battery charging mode based on the vehicle state;
A deviation arithmetic unit for calculating an engine friction torque deviation based on an engine output torque and a motor charging torque; And
A torque learning unit for learning an engine friction torque based on the engine friction torque deviation;
And an engine friction torque learning device. The method according to claim 1,
The vehicle controller
A torque calculation unit for calculating the engine output torque based on a target charging torque and an engine friction setting torque; And
A torque detector for detecting the motor charge torque by driving the drive motor based on the engine speed and the engine target speed;
Further comprising: an engine friction torque estimating device for estimating the frictional torque of the vehicle. 3. The method of claim 2,
The deviation calculation unit
Calculates an engine friction drive torque according to the engine output torque and the motor charge torque, and calculates the engine friction torque deviation based on the engine friction drive torque and the engine friction set torque. The method according to claim 1,
The torque learning unit
And the engine friction torque is learned based on the engine friction setting torque and the engine friction torque deviation. Determining whether the vehicle condition satisfies a torque learning entry condition;
Calculating an engine output torque when the vehicle condition meets a torque learning entry condition;
Detecting a motor charge torque based on an engine speed and an engine target speed;
Calculating an engine friction torque deviation based on the engine output torque and the motor charging torque;
Learning engine friction torque based on the engine friction torque deviation;
Wherein the engine friction torque learning method comprises the steps of: 6. The method of claim 5,
The step of calculating the engine output torque
Confirming a preset target charging torque and an engine friction setting torque; And
Calculating an engine output torque based on the target charging torque and an engine friction setting torque;
Wherein the engine friction torque learning method comprises the steps of: The method according to claim 6,
The step of computing the engine friction torque deviation
Computing an engine friction drive torque based on the engine output torque and the motor charge torque; And
Computing an engine friction torque deviation based on the engine friction drive torque and the engine friction set torque;
A method of learning an engine friction torque of a vehicle. The method according to claim 6,
The step of computing the engine friction torque deviation
Calculating an engine friction drive torque by subtracting the motor charge torque from the engine output torque; And
Subtracting the engine friction set torque from the engine friction drive torque to calculate an engine friction torque deviation;
Wherein the engine friction torque learning method comprises the steps of: 6. The method of claim 5,
The step of learning the engine friction torque
And updating and storing the engine friction torque based on the engine friction set torque and the engine friction torque deviation. 6. The method of claim 5,
The step of learning the engine friction torque
Adding the engine friction set torque and the engine friction torque deviation to generate an engine friction calculation torque; And
Updating the engine friction torque with the engine friction calculation torque;
Wherein the engine friction torque learning method comprises the steps of: 6. The method of claim 5,
The step of detecting the motor charging torque
Confirming the motor torque based on the engine speed and the engine target speed; And
Controlling the speed of the driving motor based on the motor torque to detect the output torque of the motor;
Wherein the engine friction torque learning method comprises the steps of: 6. The method of claim 5,
The step of determining whether the vehicle condition is satisfied with the torque learning entry condition
Wherein the vehicle condition is a step of determining whether the vehicle is at a stop and a battery charging mode and the engine is a part load. Determining whether the vehicle state is at rest and in a battery charging mode;
Determining whether the engine is in a part load state when the vehicle is in a stopped state and in a battery charging mode;
Calculating an engine output torque based on a target charging torque and an engine friction setting torque when the engine is in a part load state;
Controlling a motor speed based on an engine target speed and an engine speed to detect a motor charging torque;
Calculating an engine friction torque deviation based on the motor impact torque and the motor charging torque; And
Updating the engine friction torque based on the engine friction torque deviation to perform learning of the engine friction torque;
Wherein the engine friction torque learning method comprises the steps of:

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