KR20190072804A - Method and apparatus for controlling mhsg of mild hybrid electric vehicle - Google Patents

Abstract

The present invention relates to a method for controlling a mild hybrid starter and generator (MHSG) of a mild hybrid vehicle and an apparatus thereof, which can prevent danger arising from an automatic halt of a vehicle on an uphill road which is highly slanted. The method for controlling an MHSG of a mild hybrid vehicle according to an embodiment of the present invention may comprises the following steps of: detecting information about the speed of a vehicle; determining whether the speed of the vehicle is below a predetermined low speed based on the detected information about the speed of the vehicle; detecting information as to a driving situation or a driving environment of the vehicle; determining whether the road on which the vehicle is driving is an uphill road based on the information about a driving situation or a driving environment of the vehicle; detecting information about the inclination of the road on which the vehicle is driving; determining whether the inclination of the road exceeds a predetermined angle based on the information about the inclination of the road on which the vehicle is driving; prohibiting an automatic halt by means of an idle stop and go (ISG) function of an MHSG; and determining whether the speed of the vehicle exceeds a predetermined high speed.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a MHSG control method and apparatus for a mild hybrid vehicle,

The present invention relates to a method and an apparatus for controlling an MHSG of a mild hybrid vehicle, and more particularly, to a method and an apparatus for controlling an MHSG of a mild hybrid vehicle capable of preventing a danger of automatic stopping of a vehicle on an ascending road having a high gradient will be.

As is known, a hybrid electric vehicle uses an internal combustion engine together with a battery power source. That is, the hybrid vehicle uses the power of the internal combustion engine and the power of the motor in an efficient combination.

Hybrid vehicles can be classified into a mild type and a hard type according to the power sharing ratio between the engine and the motor. A hybrid vehicle of a mild type (hereinafter referred to as a mild hybrid vehicle) is provided with a mild hybrid starter & generator (MHSG) which starts the engine instead of the alternator or is generated by the output of the engine. The hybrid vehicle of the hard type is provided with a starter generator that starts the engine or generates power by the output of the engine and a drive motor that drives the vehicle.

Mild hybrid vehicles use MHSG to assist the engine torque according to driving conditions and to charge the battery through regenerative braking. Thus, the energy efficiency of the mild hybrid vehicle can be improved.

The control by the MHSG includes an idle stop and go (ISG) function. If the ISG function is performed on an uphill road with a high gradient, the vehicle may be pushed rearward and cause danger.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an MHSG control method and apparatus for a mild hybrid vehicle capable of preventing a danger of an automatic stop of a vehicle on an ascending road having a high gradient, .

According to another aspect of the present invention, there is provided an MHSG control method for a mild hybrid vehicle, comprising: detecting information about a speed of a vehicle; detecting a speed of the vehicle based on information on the speed of the detected vehicle; A step of determining whether a road running on the basis of information on a running condition or a running environment of the vehicle is ascending; A step of detecting information on the inclination of the road; a step of judging whether inclination of the road exceeds a set angle based on the information of inclination of the traveling road; and a step of prohibiting automatic stop according to the ISG function of the MHSG And determining whether the vehicle speed exceeds the setting speed.

The MHSG control method of the mild hybrid vehicle according to the embodiment of the present invention can be started when the engine is in a low load state.

If it is determined that the vehicle speed is not less than the set low speed, it may be determined that the vehicle speed exceeds the set high speed.

The MHSG control method of the mild hybrid vehicle according to the embodiment of the present invention may be terminated when it is determined that the vehicle speed exceeds the set high speed.

The MHSG control method of the mild hybrid vehicle according to the embodiment of the present invention can be restarted when it is determined that the vehicle speed does not exceed the set high speed.

If it is determined that the vehicle speed is lower than the set low speed, a step of detecting information on the running state or the running environment of the vehicle may be performed.

If it is determined that the road on which the vehicle is traveling is not uphill, a step of determining whether the vehicle speed exceeds the set high speed may be performed.

If it is determined that the running road is uphill, a step may be performed in which information on the inclination of the running road is detected.

If it is determined that the inclination of the road exceeds the set angle, a step may be performed in which it is determined whether the vehicle speed exceeds the set high speed after the automatic stop according to the ISG function is prohibited.

If it is determined that the inclination of the road does not exceed the set angle, the step of determining whether the road on which the vehicle is traveling may be performed again.

A control may be preceded by delaying the release of the brake before the step of determining whether the road on which it is traveling is ascending is performed again.

The setting low speed, the setting angle, and the setting speed may be preset values.

An MHSG control apparatus for a mild hybrid vehicle according to an embodiment of the present invention includes a data detection unit for detecting data for controlling an MHSG generated by an engine or by starting an engine; And stop the automatic stop control when the automatic stop prohibition condition is satisfied.

The controller may determine whether a condition for delaying the release of the brake is satisfied, and may delay the release of the brake if the brake release delay condition is satisfied.

The data detecting unit includes a brake pedal position sensor for transmitting operation request information for the brake to the controller, a vehicle speed sensor for transmitting speed information of the vehicle to the controller, a gradient sensor for transmitting road gradient information to the controller, And navigation for transmitting the driving environment information to the controller.

The controller may determine whether the brake release delay condition is satisfied by integrating information received from the brake pedal position sensor, the vehicle speed sensor, the gradient sensor, and the navigation.

The data detecting unit may include a vehicle speed sensor for transmitting speed information of the vehicle to the controller, a gradient sensor for transmitting the road gradient information to the controller, and a navigation unit for transmitting the driving environment information to the controller.

The controller can determine whether the automatic stop prohibition condition is satisfied by integrating the information transmitted from the vehicle speed sensor, the gradient sensor, and the navigation.

As described above, according to the embodiment of the present invention, the automatic stop control by the MHSG is selectively prohibited, and the release of the brake is delayed, so that the safety of the vehicle can be improved in an uphill road with a high gradient.

1 is a block diagram showing a mild hybrid vehicle according to an embodiment of the present invention.
2 is a block diagram showing an MHSG control apparatus of a mild hybrid vehicle according to an embodiment of the present invention.
3 is a flowchart of an MHSG control method of a mild hybrid vehicle according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. However, the present invention is not limited to the embodiments described herein but may be embodied in other forms.

In order to clearly illustrate the present invention, parts not related to the description are omitted, and the same or similar components are given the same reference numerals throughout the specification.

In addition, since the components shown in the drawings are arbitrarily shown for convenience of explanation, the present invention is not necessarily limited to those shown in the drawings.

1 is a block diagram showing a mild hybrid vehicle according to an embodiment of the present invention.

1, a mild hybrid vehicle according to an embodiment of the present invention includes an engine 10, a transmission 20, a mild hybrid starter & generator 30, a battery 40, a differential gear device 50 ), And a wheel 60.

The engine 10 burns fuel and air to convert chemical energy into mechanical energy. The ignition timing, the air amount, the fuel amount, and the air / fuel ratio, and the like, so that the combustion torque of the engine 10 can be generated.

The power transmission of the mild hybrid vehicle is such that the torque generated in the engine 10 is transmitted to the input shaft 25 of the transmission 20 and the torque output from the output shaft 27 of the transmission 20 is transmitted to the differential gear device 50 To the axle. The mild hybrid vehicle is driven by the torque generated by the engine 10 by rotating the wheel 60 with the axle.

The transmission (20) includes a shift clutch (21) and a gear train (23). The shift clutch 21 is disposed between the engine 10 and the gear train 23 and selectively connects the engine 10 and the gear train 23. That is, the shift clutch 21 selectively transmits the torque generated in the engine 10 to the gear train 23. [ The gear train 23 changes the gear ratio according to the running state of the mild hybrid vehicle, so that the shifting to the target speed change stage is realized.

The MHSG 30 converts electrical energy into mechanical energy or mechanical energy into electrical energy. The MHSG 30 can start the engine 10 or generate power by the output of the engine 10. [ In addition, the MHSG 30 may assist the torque of the engine 10. [ The mild hybrid vehicle can use the torque of the MHSG 30 as an auxiliary power while making the combustion torque of the engine 10 the main driving force. The engine 10 and the MHSG 30 may be connected via a belt 32.

The battery 40 may be charged via electricity supplied to the MHSG 30 or recovered through the MHSG 30 in a regenerative braking mode. The battery 40 may be a 48 V battery. The mild hybrid vehicle may further include a low voltage DC-DC converter (LDC) for converting a voltage supplied from the battery 40 to a low voltage and a 12 V battery for supplying a low voltage to a battery load using a low voltage.

2 is a block diagram of an MHSG control apparatus of a mild hybrid vehicle according to an embodiment of the present invention.

As shown in FIG. 2, the MHSG control apparatus according to the embodiment of the present invention includes a data detecting unit 70 and a controller 80.

The data detector 70 detects data for controlling the MHSG 30 and the brake 90 and the data detected by the data detector 70 is transmitted to the controller 80. The data detector 70 includes a TPEG (Transport Protocol Expert Group) 71, a brake pedal position sensor 72, a vehicle speed sensor 73, a gradient sensor 75, a navigation 77 and an engine speed sensor 79 .

The TPEG 71 is a device for displaying real-time traffic information, travel information, and driving conditions on an automobile display using a DMB broadcasting frequency. The TPEG 71 is a device having a person skilled in the art ), So that a detailed description thereof will be omitted. Here, the display may be a navigation 77, and the TPEG 71 transmits real-time traffic information, travel information, driving conditions, etc. to the controller 80.

The brake pedal position sensor 72 detects the position value of the brake pedal (not shown) (i.e., the degree to which the brake pedal is depressed) and transmits a signal to the controller 80. When the brake pedal is fully depressed, the position value of the brake pedal is 100%, and when the brake pedal is not depressed, the position value of the brake pedal is 0%.

The vehicle speed sensor 73 detects the speed of the mild hybrid vehicle and transmits a signal to the controller 80.

The gradient sensor 75 detects the inclination of the road and transmits a signal to the controller 80.

The navigation unit 77 detects the traveling environment information using the GPS signal and transmits the information to the controller 80. Other basic functions of the navigation 77 will be apparent to those skilled in the art and will not be described in detail.

The engine speed sensor 79 detects the speed of the engine 10 and the load condition of the engine 10 and transmits a signal to the controller 80.

The controller 80 controls the MHSG 30 and the brake 90 on the basis of the data detected by the data detector 70. Here, the brake 90 for performing the braking of the vehicle in accordance with the position value of the brake pedal is obvious to those skilled in the art, so a detailed description thereof will be omitted. The controller 80 can determine whether the release delay condition of the brake 90 is satisfied based on the data and determine whether the condition for prohibiting the automatic stop control according to the idle stop and go function is satisfied . For this purpose, the controller 80 may be implemented with one or more processors operating according to the set program, and the set program may be implemented in each step included in the MHSG control method of the mild hybrid vehicle according to the embodiment of the present invention Lt; RTI ID = 0.0 > commands. ≪ / RTI >

3 is a flowchart of an MHSG control method of a mild hybrid vehicle according to an embodiment of the present invention.

As shown in FIG. 3, the MHSG control method of the mild hybrid vehicle according to the embodiment of the present invention starts when the engine 10 is in a low load state (S100). Here, the controller 80 receives the information on the load state of the engine 10 from the engine speed sensor 79, and can determine the low load state of the engine 10.

When the MHSG control method of the mild hybrid vehicle according to the embodiment of the present invention is started (S100), the controller 80 detects information on the speed of the mild hybrid vehicle from the vehicle speed sensor 73 (S110). In addition, the controller 80 determines whether the vehicle speed is less than a set low speed based on information on the speed of the mild hybrid vehicle transmitted from the vehicle speed sensor 73 (S120). Here, the set low speed is a value previously stored in the controller 80 by a person skilled in the art.

If it is determined that the vehicle speed is not lower than the set low speed, the controller 80 determines whether the vehicle speed exceeds the setting speed based on information on the speed of the mild hybrid vehicle transmitted from the vehicle speed sensor 73 in step S130. Here, the setting speed is a value previously set by a person skilled in the art and stored in the controller 80.

If it is determined that the vehicle speed exceeds the setting high speed, the controller 80 determines that the engine 10 is out of the low load state and ends the MHSG control method of the mild hybrid vehicle according to the embodiment of the present invention (S200) . On the other hand, if it is determined that the vehicle speed does not exceed the setting speed, the MHSG control method of the mild hybrid vehicle according to the embodiment of the present invention is returned to the start step S100. Herein, the termination of the MHSG control method of the mild hybrid vehicle according to the embodiment of the present invention is performed before the MHSG control method of the mild hybrid vehicle according to the embodiment of the present invention is started by the general control of the MHSG 30 and the brake 90 Is performed.

If it is determined that the vehicle speed is lower than the set lower speed, the controller 80 detects information on the running condition or running environment of the mild hybrid vehicle from the TPEG 71 or the navigation 77 (S140). In addition, the controller 80 determines whether the road traveling on the basis of the driving situation of the mild hybrid vehicle or the driving environment transmitted from the TPEG 71 or the navigation 77 is uphill (S150).

If it is determined that the road on which the vehicle is traveling does not ascend, the controller 80 performs step S130 of determining whether the vehicle speed exceeds the set speed.

If it is determined that the road on which the vehicle is traveling is ascending, the controller 80 detects information on the inclination of the road on which the mild hybrid vehicle travels from the gradient sensor 75 (S160). In step S170, the controller 80 determines whether the inclination of the road exceeds a predetermined angle based on information on the inclination of the road on which the mild hybrid vehicle is transmitted from the gradient sensor 75. Here, the setting angle is a value previously set by the person skilled in the art and stored in the controller 80.

If it is determined that the inclination of the road exceeds the set angle, the controller 80 prohibits the automatic stop control according to the ISG function of the MHSG 30 (S180) and then determines whether the vehicle speed exceeds the set speed ). On the other hand, if it is determined that the inclination of the road does not exceed the set angle, the controller 80 performs control for delaying the release of the brake 90, and thereafter controls the MHSG control of the mild hybrid vehicle according to the embodiment of the present invention The method is performed again from step S150 in which it is determined whether the road on which the vehicle is traveling is ascending. Here, the control for delaying the release of the brake 90 is started when the brake 90 is released from the time point when the position value of the brake pedal transmitted from the brake pedal position sensor 72 becomes 0% at a value exceeding 0% This control prevents the vehicle from being pushed backward until the accelerator pedal (not shown) is depressed after the position value of the brake pedal reaches 0% even if automatic stop control according to the ISG function is performed. do.

As described above, according to the embodiment of the present invention, the automatic stop control by the MHSG 30 is selectively prohibited, and the release of the brake 90 is delayed, so that the safety of the vehicle is improved in a high gradient road .

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, And all changes to the scope that are deemed to be valid.

10: engine 20: transmission
30: MHSG 40: Battery
50: Differential gear device 60: Wheel
70:
71: TPEG 72: Brake pedal position sensor
73: vehicle speed sensor 75: gradient sensor
77: Navigation 79: Engine speed sensor
80: Controller 90: Brake

Claims (18)

Detecting information on the speed of the vehicle;
Determining whether the vehicle speed is less than a set low speed based on information on the detected vehicle speed;
Detecting information on a running state or a running state of the vehicle;
Determining whether a road traveling on the basis of information on the driving situation or the driving environment of the vehicle is uphill;
Detecting information about a slope of a running road;
Determining whether the inclination of the road exceeds a set angle based on the information on the inclination of the running road;
Prohibiting automatic stop according to the ISG function of the MHSG; And
Determining whether the vehicle speed exceeds a setting speed;
Wherein the MHSG control method comprises the steps of: The method according to claim 1,
Wherein the engine is started when the engine is in a low load state. The method according to claim 1,
And if it is determined that the vehicle speed is not lower than the set low speed, the step of determining whether the vehicle speed exceeds the set high speed is performed. The method according to claim 1,
And terminates when it is determined that the vehicle speed exceeds the set speed. The method according to claim 1,
And restarts when it is determined that the vehicle speed does not exceed the set high speed. The method according to claim 1,
Wherein the step of detecting information on a running state or a running environment of the vehicle is performed when it is determined that the vehicle speed is lower than the set low speed. The method according to claim 1,
Wherein the step of determining whether the vehicle speed exceeds the set high speed is performed when it is determined that the traveling road is not an uphill. The method according to claim 1,
Wherein the step of detecting information on the inclination of the road to be driven is performed when it is determined that the road on which the vehicle is traveling is ascending. 9. The method of claim 8,
Wherein the step of determining whether the vehicle speed exceeds the set high speed is performed after the automatic stop according to the ISG function is prohibited if it is determined that the inclination of the road exceeds the set angle. 9. The method of claim 8,
Wherein when it is determined that the inclination of the road does not exceed the set angle, the step of determining whether the road on which the vehicle is traveling is ascending is performed again. 11. The method of claim 10,
Characterized in that the control for delaying the release of the brake is performed before the step of judging whether the road on which the vehicle is traveling is ascending is performed again. The method according to claim 1,
Wherein the set low speed, the set angle, and the set high speed are pre-set stored values. A data detection unit for detecting data for controlling the MHSG that starts the engine or is generated by the output of the engine; And
A controller for determining whether a condition for prohibiting automatic stop control according to the ISG function of the MHSG is satisfied based on the data, and prohibiting automatic stop control when the automatic stop prohibition condition is satisfied;
And the MHSG control device of the mild hybrid vehicle. 14. The method of claim 13,
Wherein the controller determines whether a condition for delaying the release of the brake is satisfied and delays the release of the brake when the brake release delay condition is satisfied. 15. The method of claim 14,
Wherein the data detecting unit comprises:
A brake pedal position sensor for transmitting operation request information for the brake to the controller;
A vehicle speed sensor for transmitting speed information of the vehicle to the controller;
A gradient sensor for transmitting road gradient information to the controller; And
Navigation for transmitting driving environment information to the controller;
And an MHSG controller for controlling the MHSG of the mild hybrid vehicle. 16. The method of claim 15,
Wherein the controller is configured to determine whether the brake release delay condition is satisfied by integrating information received from the brake pedal position sensor, the vehicle speed sensor, the gradient sensor, and the navigation device. 14. The method of claim 13,
Wherein the data detecting unit comprises:
A vehicle speed sensor for transmitting speed information of the vehicle to the controller;
A gradient sensor for transmitting road gradient information to the controller; And
Navigation for transmitting driving environment information to the controller;
And an MHSG controller for controlling the MHSG of the mild hybrid vehicle. 18. The method of claim 17,
Wherein the controller is configured to determine whether the automatic stop prohibition condition is satisfied by synthesizing information transmitted from the vehicle speed sensor, the gradient sensor, and the navigation.

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