KR102568959B1 - Method and apparatus for controlling rpm flare of mild hybrid electric vehicle - Google Patents

Abstract

The present invention relates to a method and apparatus for controlling RPM flare of a mild hybrid vehicle for controlling generation of RPM flare in a mild hybrid vehicle to which an intelligent manual transmission is applied. The present invention provides an engine, an MHSG that transmits power to the engine or generates power by the output of the engine, an automated manual transmission, an ECU that controls the engine, an MCU that controls the MHSG, and controls the automated manual transmission. In the RPM flare control apparatus of a mild hybrid vehicle including a TCU, it is determined whether flare control activation for preventing RPM flare of the engine is necessary according to a clutch operation signal of the automated manual transmission and a shift lever operation signal of the automated manual transmission and a flare control unit that calculates a target MHSG torque for preventing the RPM flare and provides it to the MCU.

Description

RPM flare control method and apparatus for mild hybrid vehicle {METHOD AND APPARATUS FOR CONTROLLING RPM FLARE OF MILD HYBRID ELECTRIC VEHICLE}

The present invention relates to a method and apparatus for controlling RPM flare of a mild hybrid vehicle. More specifically, the present invention relates to a method and apparatus for controlling RPM flare of a mild hybrid vehicle for controlling generation of RPM flare in a mild hybrid vehicle to which an intelligent manual transmission is applied.

A hybrid vehicle may be classified into a mild type and a hard type according to a power sharing ratio between an engine and a motor. A mild hybrid vehicle (hereinafter, referred to as a mild hybrid vehicle) includes a mild hybrid starter & generator (MHSG) that starts an engine or generates power by an output of an engine instead of an alternator. A hybrid vehicle of the hard type includes a starter generator that starts an engine or generates electricity by an output of the engine and a drive motor that drives the vehicle.

Mild hybrid vehicles do not have a driving mode in which the vehicle is driven only by the torque of the MHSG, but engine torque can be assisted according to the driving condition using the MHSG, and the battery (EX: 48V battery) can be charged through regenerative braking. Accordingly, fuel efficiency of the mild hybrid vehicle may be improved.

Meanwhile, an intelligent manual transmission (iMT) is a manual transmission in which an actuator operates a clutch that transmits power from an engine to a transmission. It is different from a conventional manual transmission in which a driver directly connects and disconnects a clutch by a wire connected to the clutch pedal by stepping on the clutch pedal. In the case of using an intelligent manual transmission, driving pleasure and fuel efficiency improvement according to manual transmission can be obtained, and difficulties in clutch operation during manual transmission can be solved.

Registered Patent No. 10-2221400

The RPM flare phenomenon refers to an unintentional increase in engine RPM due to residual torque of the engine while the clutch is released during the gear shifting process. In a vehicle equipped with a manual transmission, the clutch falls off during shifting and the power connection is cut off. The target torque of the vehicle quickly converges to 0, but the engine demand torque does not immediately drop to 0 due to the driver's demand torque filter. Accordingly, residual torque exists in the engine and RPM flare occurs.

As a way to prevent this, it may be considered to perform fuel cut-off at the moment when the accelerator pedal is not applied and the clutch is operated to disengage. However, during the corresponding cutoff, oxygen introduced into the three-way catalyst of the exhaust system is accumulated. In order to maintain the exhaust gas purification efficiency of the three-way catalyst, it is necessary to maintain a constant oxygen concentration in the three-way catalyst. Therefore, when the accelerator pedal is input after the fuel cutoff, the air-fuel ratio must be richly controlled for a certain period of time to remove oxygen in the three-way catalyst during fuel injection (catalyst purge). However, this has a problem of deteriorating fuel economy.

In order to solve this problem, the present invention proposes a method for controlling RPM flare in a vehicle to which iMT is applied.

Accordingly, an object of the present invention is to provide a method and apparatus for controlling RPM flare of a mild hybrid vehicle for controlling generation of RPM flare in a mild hybrid vehicle to which an intelligent manual transmission is applied.

The present invention provides an engine, an MHSG that transmits power to the engine or generates power by the output of the engine, an automated manual transmission, an ECU that controls the engine, an MCU that controls the MHSG, and controls the automated manual transmission. In the RPM flare control apparatus of a mild hybrid vehicle including a TCU, it is determined whether flare control activation for preventing RPM flare of the engine is necessary according to a clutch operation signal of the automated manual transmission and a shift lever operation signal of the automated manual transmission and a flare control unit that calculates a target MHSG torque for preventing the RPM flare and provides it to the MCU.

In one embodiment, the flare control unit may include: a flare control activation unit determining whether the flare control activation is necessary; an RPM modeling unit modeling prediction engine RPM at which the RPM flare does not occur, by using the RPM of the engine as an initial value at the time of flare control activation when it is determined that the flare control activation is necessary; a flare control determination unit determining whether control of the MHSG is necessary to prevent the RPM flare based on a difference between the predicted engine RPM and the actual engine RPM after the flare control activation time; and a target torque calculator configured to calculate the target MHSG torque.

Also, the flare control activator may determine whether the flare control needs to be activated in consideration of the clutch actuation signal, the shift lever actuation signal, and an accelerator pedal amount.

In addition, the flare control activation unit may consider the accelerator pedal amount at the time of determining whether the flare control activation is necessary, the accelerator pedal amount before that, or the amount of change in the accelerator pedal amount.

In addition, the flare control activator may further consider an engine torque at a time point of determining whether the flare control activation is necessary and an engine torque before that.

In addition, the flare control activation unit may further consider a charge amount of a battery connected to the MHSG.

In one embodiment, the flare control activation unit may terminate the flare control activation when the actual engine RPM of the engine reaches a flare control release RPM.

In one embodiment, the RPM modeling unit sets the engine RPM at the time of activation of the flare control as an initial value, the vehicle speed of the vehicle, the acceleration of the vehicle, the road slope on which the vehicle travels, and immediately before the automated manual transmission The predicted engine RPM may be modeled by considering at least one of the number of gears and the number of new gears to be shifted.

In one embodiment, the target torque calculator calculates a road slope on which the vehicle travels based on a difference between the predicted engine RPM and the actual engine RPM after the flare control activation time point, and at or after the flare control activation time point. The target MHSG torque may be calculated by further considering at least one of , the reduction amount of the actual engine RPM, and the time required from the activation of the flare control to the clutch operation.

In addition, the present invention is a method for controlling the RPM flare of the vehicle engine by the flare control unit of a mild hybrid vehicle having an MHSG and an automated manual transmission, (a) for controlling the RPM flare from the driving state of the vehicle determining whether flare control activation is required; (b) generating a predicted engine RPM by modeling the RPM of the engine when the flare control is activated; (c) calculating a target MHSG torque for the RPM flare control based on a difference between the actual engine RPM after the flare control activation point and the predicted engine RPM; and (d) controlling the MHSG according to the target MHSG torque.

In one embodiment, in step (a), the accelerator pedal at the time of determination in step (a) is in an off state, the accelerator pedal before that is in an on state, and the automated manual transmission When there is a clutch operation signal of , it may be determined that the flare control activation is necessary.

Further, the step (a) may be determined in consideration of the accelerator pedal amount at the time of determination of the step (a), the accelerator pedal amount before that, and the amount of change in the accelerator pedal amount.

In addition, in the step (a), it may be determined that the flare control is required to be activated on the condition that the gear range of the automated manual transmission is shifted.

In one embodiment, the control method further includes (e) terminating the flare control activation when the actual engine RPM reaches a flare control release RPM.

In addition, in the step (b), the engine RPM at the time of activating the flare control is set as an initial value, the vehicle speed of the vehicle, the acceleration of the vehicle, the road slope on which the vehicle travels, and the previous gear stage of the automated manual transmission The predicted engine RPM may be modeled by considering at least one of the new gear stage to be shifted to.

In addition, the step (c) is based on the difference between the predicted engine RPM and the actual engine RPM after the flare control activation time, and the road slope on which the vehicle travels at or after the flare control activation time, the actual The target MHSG torque may be calculated by further considering at least one of a decrease in engine RPM and a time required from the point of time when the flare control is activated to when the clutch is operated.

According to the present invention, in a mild hybrid vehicle equipped with an intelligent manual transmission, drivability can be improved through effective RPM flare control during shifting. In addition, it is possible to charge the battery by controlling the directional torque of the MHSG for RPM flare control.

In addition, according to the present invention, since it is not necessary to perform cutoff to control RPM flare, fuel efficiency can be improved because the air-fuel ratio enrichment control due to catalyst purge after cutoff is unnecessary.

1 is a diagram showing an example of a mild hybrid vehicle to which the present invention is applied.
2 is a flowchart illustrating a method for controlling RPM flare of a mild hybrid vehicle according to an embodiment of the present invention.
3 is a diagram for explaining application of an RPM flare control method for a mild hybrid vehicle according to an embodiment of the present invention.
4 is a block diagram showing the configuration of a flare control unit constituting an RPM flare control device according to an embodiment of the present invention.
5 is a diagram illustrating a process of determining whether a flare control is activated by a flare control activation unit of a flare control unit in an RPM flare control apparatus according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, in adding reference numerals to components of each drawing, it should be noted that the same components have the same numerals as much as possible even if they are displayed on different drawings. In addition, in describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description will be omitted. In addition, although preferred embodiments of the present invention will be described below, the technical idea of the present invention is not limited or limited thereto and can be modified and implemented in various ways by those skilled in the art.

1 is a diagram showing an example of a mild hybrid vehicle to which the present invention is applied.

The mild hybrid vehicle includes an engine 10 , a mild hybrid starter & generator (MHSG) 12 , a battery 14 and a transmission 16 . In addition, the mild hybrid vehicle may further include an engine control unit (ECU) 20, a motor control unit 30 (MCU), a transmission control unit (TCU) 40, and a flare control unit 50 for preventing RPM flare. can

The power generated by the engine 10 is transmitted to the axle via the transmission 16 .

The MHSG 12 may start the engine 10 or generate power by output of the engine 10 . MHSG 12 may assist torque of engine 10 in a manner that assists output of engine 10 . The battery 14 supplies power to the MHSG 12 or stores power generated in the MHSG 12, for example, the battery 14 may be a 48V lithium-ion battery.

The transmission 16 may be configured as an intelligent manual transmission (iMT). In the intelligent manual transmission, an actuator operates to control a clutch when a shift lever is operated or a driver presses a clutch pedal for gear shifting, and gear shifting is performed by the shift lever.

ECU 20 controls the operation of engine 10 . The ECU sets the target torque based on information such as the accelerator pedal sensor, clutch position sensor, vehicle speed sensor, crankshaft position (CKP) sensor, camshaft position (CMP) sensor, etc. The operation of the engine 10, such as the amount of injection, is controlled.

The MCU 30 controls the operation of the MHSG 12 according to the control mode of the MHSG 12. Under the control of the MCU 30, the MHSG 12 performs operations such as start-up of the engine 10, power generation using output torque of the engine 10, or torque assistance of the engine 10.

The TCU 40 controls the operation of the transmission 16. The TCU 40 may recognize the position of the shift lever provided in the driver's seat and control the operation of the clutch of the transmission 16 according to the operation of the shift lever or the operation of the clutch pedal. In the iMT type transmission 16, the clutch is operated under the control of the TCU 40 according to the shift position of the shift lever or the operation of the iMT clutch pedal provided in the vehicle.

The flare control unit 50 determines whether RPM flare control is necessary based on the information transmitted from the ECU 20, the MCU 30, and the TCU 40, and the engine 10 or MHSG 12 for RPM flare control of control information. Control information of the flare control unit 50 is transferred to the MCU 30 and the MHSG 12 is controlled. In one embodiment, the flare control unit 50 may set a target torque of the MHSG 12 and transmit it to the MCU 30 when RPM flare is expected to occur and it is determined that it is necessary to prevent the RPM flare. The MCU 30 controls the MHSG 12 to drive the MHSG 12 so that RPM flare in the engine 10 does not occur. In one embodiment, when the MHSG 12 generates power using the torque of the engine 10, RPM flare can be prevented by providing reverse driving torque to the engine 10.

2 is a flowchart illustrating a method for controlling RPM flare of a mild hybrid vehicle according to an embodiment of the present invention.

RPM flare control by the flare controller 50 is in a deactivated state (S10).

The flare control unit 50 determines the driving state of the vehicle based on information transmitted from the ECU 20, the MCU 30, and the TCU 40 (S20).

The information transmitted from the ECU 20 may include accelerator pedal sensor information, current engine torque, target engine torque, current vehicle torque, target vehicle torque, current engine RPM, engine target RPM, and the like. The information transmitted from the MCU 30 may include information such as a current control mode of the MHSG 12, a target control mode, a target MHSG talk, and a current MHSG talk. The information transmitted from the TCU 40 may include shift lever position information, clutch operation information, and the like.

The flare control unit 50 determines whether it is necessary to activate the RPM flare control based on the information transmitted from the ECU 20, the MCU 30, and the TCU 40 (S14). As an example of the case where it is determined that it is necessary to activate the RPM flare control, the previous accelerator pedal state is 'On', the current accelerator pedal state is "Off", and the current clutch state is operating due to the shift request of the iMT (clutch is dropped). state) may be the case.

If it is determined in step S14 that there is no need to activate the RPM flare control, step S10 is maintained. In step S14, when it is determined that activation of RPM flare control is necessary, the flare control of the flare control unit 50 is activated (S16).

The flare control unit 50 models the engine RPM after the RPM flare control is activated (S18). The modeled engine RPM is the engine RPM at which RPM flare may not occur, and the engine RPM predicted to operate without RPM flare occurring after the point at which RPM flare control is activated (the point at which flare control is activated) (predicted engine RPM) can be

In one embodiment, the predicted engine RPM to be modeled is engine RPM after being predicted based on the engine RPM at the time of activation of flare control as an initial value and the actual engine RPM before or after the time of activation of flare control. can Modeling of the engine RPM may be performed based on an RPM change amount (decrease amount) for a predetermined time after RPM flare control is activated. In addition, engine RPM modeling may be performed in consideration of vehicle speed, acceleration, road gradient, gear stage, clutch operating time, etc. at or before or after the flare control is activated.

It is determined whether the difference between the actual engine RPM and the predicted engine RPM after the flare control activation point is out of a reference value (S20). If the difference between the actual engine RPM and the predicted engine RPM is not large under the condition that RPM flare can occur according to the iMT shift, it means that the RPM flare does not occur and the engine RPM naturally decreases during the shift process. However, if the difference between the actual engine RPM and the predicted engine RPM is greater than the reference value, it means that the RPM flare is highly likely to occur.

If the difference between the actual engine RPM and the predicted engine RPM is greater than the reference value in step S20, the flare control unit 50 calculates a target MHSG torque for RPM flare control according to the difference between the actual engine RPM and the predicted engine RPM (S24). The target MHSG torque may be understood as a reverse drive torque capable of reducing engine RPM.

The flare control unit 50 transmits the target MHSG torque to the MCU 30 (S26), and the MCU 30 controls the MHSG 12 to provide reverse driving torque to the engine 10 (S28). At this time, the MHSG 12 may generate power according to the reverse driving torque and store it in the battery 14 .

3 is a diagram for explaining application of an RPM flare control method for a mild hybrid vehicle according to an embodiment of the present invention.

(a) of FIG. 3 shows the transition of engine RPM after the point at which the clutch is applied for shifting of the iMT. This means that the clutch is applied for shifting at time t0 and the RPM flare control is activated at time t0. The predicted engine RPM indicates modeling of an engine RPM at which RPM flare does not occur using the engine RPM at t0 and other vehicle condition information. In this respect, the actual engine RPM represents the actual RPM of the engine. When a deviation occurs between the actual engine RPM and the predicted engine RPM, and the deviation is greater than or equal to a reference value, it may be determined that an RPM flare may occur. A deviation between the actual engine RPM and the predicted engine RPM may be determined at time t1. If the deviation as a result of the determination at t1 is greater than or equal to the reference value, the MHSG 12 may be controlled for RPM flare control.

The flare control release RPM may be set, and at t3 the actual engine RPM reaches the flare control release RPM so that the RPM flare control is released.

Figure 3 (b) shows an example of the MHSG target torque for RPM flare control.

An existing MHSG target torque unrelated to RPM flare control may be set. In response, the first MHSG target torque for RPM flare control is calculated, and the final MHSG target torque considering the first MHSG target torque and the existing MHSG target torque is presented. In (b) of FIG. 3 , after time t1, the final MHSG target torque is controlled to follow the first MHSG target torque, and after t3, the RPM flare control is released to return to the original MHSG target torque.

Meanwhile, in the practice of the present invention, the comparison between the actual engine RPM and the predicted engine RPM may be performed at t2 after t1 or multiple times, and the target torque of the MHSG 12 may be modified accordingly.

4 is a block diagram showing the configuration of a flare control unit constituting an RPM flare control device according to an embodiment of the present invention.

The flare control unit 50 may include a flare control activation unit 52 , an RPM modeling unit 54 , a flare control determination unit 56 and a target torque calculation unit 58 . The flare control activation unit 52 determines whether activation of the RPM flare control is necessary, and activates the RPM flare control logic when it is determined that the activation of the RPM flare control is necessary. The RPM modeling unit 54 models the predicted engine RPM when RPM flare does not occur. The flare control determining unit 56 compares the predicted engine RPM with the actual engine RPM to determine whether an RPM flare occurs. The target torque calculation unit 58 calculates the MHSG target torque to be provided from the MHSG 12 in order to prevent RPM flare.

The flare control activation unit 52 determines whether activation of the RPM flare control is required. In the case of an iMT vehicle, it may be difficult to determine whether actual shifting occurs only by operating the clutch. In the case of an automatic transmission, a predetermined RPM, vehicle speed, and an accelerator pedal signal (driver's requested torque) are comprehensively determined to automatically shift gears. In a vehicle equipped with an automatic transmission, RPM information on the output side of the transmission is used, and in the case of a hybrid vehicle in which a drive motor is connected to the transmission, a change in RPM is predicted and the occurrence of RPM flare can be determined using information on the drive motor. . However, since the output side RPM of the transmission cannot be measured in the transmission to which the iMT is applied, it is necessary to determine and control the RPM flare using the engine RPM and engine control related information.

Accordingly, the flare control activating unit 52 according to the present invention provides other vehicle control information immediately before clutch application, such as an accelerator pedal amount, an accelerator pedal change amount, and an engine target before clutch application, in addition to the clutch application status. It may be necessary to predict whether an actual shift will be performed using the amount of torque, the degree of current torque reduction, and the like.

5 is a diagram illustrating a process of determining whether a flare control is activated by a flare control activation unit of a flare control unit in an RPM flare control apparatus according to an embodiment of the present invention.

The flare control activation unit 52 may check transmission information from the TCU 40 (S100). In the confirmation of the transmission information, it may be confirmed whether a clutch application request has been made or whether gear shifting is in progress. The clutch application request may be determined by whether the driver has stepped on the clutch pedal or there is a clutch operation request for shifting of the iMT transmission by operating the shift lever. In addition, whether the gear is shifted may be confirmed by the operation of the shift lever. Since flare control activation is basically for controlling the occurrence of RPM flare when the clutch is released for shifting, transmission information is a basic premise for flare control activation.

The flare control activation unit 52 can check the accelerator pedal amount (S110). The confirmed accelerator pedal amount may include at least one of a past accelerator pedal amount, a current accelerator pedal amount, and an accelerator pedal change amount. In one embodiment, when the past accelerator pedal amount is greater than the reference value, the current accelerator pedal amount is less than the reference value, and the past and present accelerator pedal change amounts are greater than the reference value, it can be seen that RPM flare is expected to occur.

In the above description and the following description, the expression "past" may be understood as the immediately preceding time based on the present, in order to determine whether or not the RPM flare is controlled, and may be a time prior to the current reference several ms to hundreds of ms. . In addition, in the above description and the following description, it should be understood that the reference value may be different for each measured quantity, and even though it is expressed as a reference value, it does not mean that all values are the same.

The flare control activation unit 52 may check the engine torque (S120). The checked engine torque may be a past engine torque amount and an engine torque reduction amount. When the past engine torque amount is greater than the reference value and the current engine torque reduction amount compared to the past is greater than the reference value, it can be seen that RPM flare is expected to occur.

The flare control activation unit 52 may check the state of the battery 14 . This is because, since the RPM flare is controlled using the MHSG 12 in the present invention, flare control can be performed using the MHSG 12 when the charged amount of the battery 14 is greater than or equal to the reference value.

In the implementation of the present invention, the flare control activation unit 52 may first determine whether to activate the flare control by synthesizing the determination results in steps S100 to S130 (S140). However, in the practice of the present invention, it may be possible to set the RPM flare control to be active not only when all conditions in steps S100 to S130 are satisfied, but also when some conditions are satisfied. In some cases, it may be possible to determine whether to activate the RPM flare control by assigning a weight to each condition.

In addition, in the implementation of the present invention, the flare control activation unit 52 may further consider whether to activate the RPM flare control in consideration of the current engine RPM (S150). In one embodiment, a map for an engine RPM reference value for RPM flare control according to engine RPM and gear stage may be utilized.

The flare control activation unit 52 synthesizes the determination results of steps S140 and S150 (S160), and activates RPM flare control when the condition is satisfied (S170).

The RPM modeling unit 54 models the engine RPM after the RPM flare control is activated and provides the predicted engine RPM. The prediction engine RPM modeled by the RPM modeling unit 54 may be the RPM of the engine 10 in a normal state where the RPM flare predicted based on the information on the activation time of the RPM flare control does not occur. The predicted engine RPM is set considering at least one of the actual engine RPM at the time when the RPM flare control is activated, the vehicle speed or vehicle acceleration, the slope of the road on which the vehicle travels, and the previous gear range and the new gear range to be shifted together. can In addition, a time required from when the logic is activated to when the clutch operates may also be considered.

In one embodiment, the RPM modeling unit 54 sets the actual engine RPM at the time of activation of the flare control as an initial value, and predicts the behavior of the RPM of the engine based on the number of gears immediately before and after the time of activation of the flare control. Also, the RPM modeling unit 54 may model the engine RPM by adjusting the slope of the engine RPM per hour according to the speed, acceleration, and/or road gradient of the vehicle with respect to the predicted engine RPM. Here, modeling of the engine RPM may be performed by adjusting the time constant of the low pass filter.

The flare control determining unit 56 compares the actual engine RPM after the RPM flare control activation point with the predicted engine RPM modeled by the RPM modeling unit 54 to determine whether to drive the MHSG 12 to prevent RPM flare or drive It is determined whether to adjust the target torque of the MHSG 12 in progress.

The target torque calculator 58 determines that the target torque of the MHSG 12 needs to be reset or changed to prevent RPM flare as a result of the determination of the flare control determiner 56. The MHSG target torque for preventing RPM flare yields

The target torque calculator 58 may calculate the MHSG target torque (the first MHSG target torque in FIG. 3(b) ) based on the difference between the actual engine RPM and the predicted engine RPM. In one embodiment, the target torque calculator 58 calculates the calculated MHSG target torque, the slope of the road on which the vehicle travels at or after the flare control activation time, the reduction amount of the actual engine RPM, and the clutch after the flare control activation time. The MHSG target torque can be corrected by considering other vehicle operating conditions and environmental factors, such as time required for operation.

The target torque calculator 58 sets the calculated MHSG target torque as the first MHSG target torque, and provides the final MHSG target torque in consideration of the existing MHSG target torque and the RPM flare control release point in FIG. 3 (b). can In addition, the target torque calculator 58 adjusts the minimum MHSG torque to be provided by the MHSG 12 and the maximum MHSG torque that the MHSG 12 can provide as the lower limit and the upper limit of the final MHSG target torque. After that, the final MHSG target torque may be provided.

The MCU 30 controls the MHSG 12 according to the final MHSG target torque provided by the target torque calculation unit 58 of the flare control unit 50, thereby preventing RPM flare during shifting in a mild hybrid vehicle to which iMT is applied. make it possible

The above description is merely an example of the technical idea of the present invention, and those skilled in the art can make various modifications, changes, and substitutions without departing from the essential characteristics of the present invention. will be. Therefore, the embodiments disclosed in the present invention and the accompanying drawings are not intended to limit the technical idea of the present invention, but to explain, and the scope of the technical idea of the present invention is not limited by these embodiments and the accompanying drawings. . The protection scope of the present invention should be construed according to the claims below, and all technical ideas within the equivalent range should be construed as being included in the scope of the present invention.

10 : engine
12: MHSG
14: battery
16: Transmission
20: ECU
30: MCU
40: TCU
50: flare control unit
52: flare control activation unit
54: RPM modeling unit
56: flare control judgment unit
58: target torque calculation unit

Claims (16)

Includes an engine, an MHSG that transmits power to the engine or generates power by the output of the engine, an automated manual transmission, an ECU that controls the engine, an MCU that controls the MHSG, and a TCU that controls the automated manual transmission In the RPM flare control device of a mild hybrid vehicle to
According to the clutch operation signal of the automated manual transmission and the shift lever operation signal of the automated manual transmission, it is determined whether it is necessary to activate flare control to prevent RPM flare of the engine, and to calculate a target MHSG torque for preventing RPM flare, the MCU Including a flare control provided by,
The flare control unit,
a flare control activating unit that determines whether the flare control needs to be activated;
an RPM modeling unit modeling prediction engine RPM at which the RPM flare does not occur, by using the RPM of the engine as an initial value at the time of flare control activation when it is determined that the flare control activation is necessary;
a flare control determination unit determining whether control of the MHSG is necessary to prevent the RPM flare based on a difference between the predicted engine RPM and the actual engine RPM after the flare control activation time; and
a target torque calculator configured to calculate the target MHSG torque;
Characterized in that it comprises a, RPM flare control device for a mild hybrid vehicle. delete According to claim 1,
The flare control activation unit determines whether or not the flare control activation is necessary in consideration of the clutch operation signal, the shift lever operation signal, and an accelerator pedal amount. According to claim 3,
The flare control activation unit considers the accelerator pedal amount at the time of determining whether the flare control activation is necessary, the accelerator pedal amount before that, or the amount of change in the accelerator pedal amount. Flare control for RPM of a mild hybrid vehicle Device. According to claim 3,
The flare control activating unit further considers an engine torque at a time of determining whether the flare control activation is necessary and an engine torque before that, the flare control device for RPM of a mild hybrid vehicle. According to claim 3,
The flare control activation unit further considers a charge amount of a battery connected to the MHSG, the RPM flare control device for a mild hybrid vehicle. According to claim 1,
The flare control activation unit terminates the flare control activation when the actual engine RPM of the engine reaches a flare control release RPM. The method according to any one of claims 1 and 3 to 7,
The RPM modeling unit sets the engine RPM at the time of activating the flare control as an initial value, and determines the speed of the vehicle, the acceleration of the vehicle, the slope of the road on which the vehicle travels, the previous gear stage of the automated manual transmission and the new gear to be shifted. An RPM flare control device for a mild hybrid vehicle, characterized in that modeling the predicted engine RPM by considering at least one of the gear stages together. The method according to any one of claims 1 and 3 to 7,
The target torque calculation unit calculates, based on a difference between the predicted engine RPM and the actual engine RPM after the flare control activation time, a road slope on which the vehicle travels at or after the flare control activation time, and the actual engine RPM. The RPM flare control device for a mild hybrid vehicle, characterized in that the target MHSG torque is calculated by further considering at least one of a reduction amount and a time required from the point of time when the flare control is activated until the clutch is operated. A method for controlling the RPM flare of a vehicle engine by a flare control unit of a mild hybrid vehicle having an MHSG and an automated manual transmission,
(a) determining whether it is necessary to activate flare control for controlling the RPM flare from the driving state of the vehicle;
(b) generating a predicted engine RPM by modeling the RPM of the engine when the flare control is activated;
(c) calculating a target MHSG torque for the RPM flare control based on a difference between the actual engine RPM after the flare control activation point and the predicted engine RPM; and
(d) controlling the MHSG according to the target MHSG torque;
RPM flare control method of a mild hybrid vehicle comprising a. According to claim 10,
In step (a), the accelerator pedal at the time of determination in step (a) is in an off state, the accelerator pedal before that is in an on state, and the clutch operation signal of the automated manual transmission is present. RPM flare control method for a mild hybrid vehicle, characterized in that it is determined that the flare control activation is necessary when According to claim 11,
The step (a) is determined in consideration of the accelerator pedal amount at the time of determination in step (a), the accelerator pedal amount before that, and the amount of change in the accelerator pedal amount. RPM flare of a mild hybrid vehicle, characterized in that control method. According to claim 11,
In step (a), it is determined that the flare control needs to be activated on the condition that the gear range of the automated manual transmission is shifted. According to claim 11,
(e) terminating the activation of the flare control when the actual engine RPM reaches the flare control release RPM. According to any one of claims 10 to 14,
In the step (b), the engine RPM at the time of activation of the flare control is set as an initial value, the vehicle speed of the vehicle, the acceleration of the vehicle, the slope of the road on which the vehicle travels, and the previous gear stage and shift of the automated manual transmission An RPM flare control method for a mild hybrid vehicle, characterized in that modeling the predicted engine RPM in consideration of at least one of the new gear stages to be selected together. According to any one of claims 10 to 14,
The step (c) is based on the difference between the predicted engine RPM and the actual engine RPM after the flare control activation time, and the road slope on which the vehicle travels at or after the flare control activation time, the actual engine RPM The method of controlling RPM flare of a mild hybrid vehicle, characterized in that the target MHSG torque is calculated by further considering at least one of a decrease in , and a time required from the flare control activation point to clutch operation.

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