KR102463719B1 - Shift control method for vehicle - Google Patents

Abstract

The present invention relates to a shift control method of a vehicle, comprising the steps of: (a) determining whether a vehicle enters a power-on upshift; (b) when it is determined that the vehicle has entered the power-on upshift, setting a compensation torque for additionally applying to the input shaft so as to constantly maintain the output shaft torque during handover; and (c) increasing the input shaft torque by the compensation torque compared to the starting point input shaft torque at the start time of the handover to perform the handover.

Description

Shift control method of vehicle {SHIFT CONTROL METHOD FOR VEHICLE}

The present invention relates to a method for controlling a shift in a vehicle.

Recently, eco-friendly vehicles are rapidly developing in accordance with environmental improvement problems. Such eco-friendly vehicles include electric vehicles or hybrid vehicles using electric energy.

In particular, the hybrid vehicle refers to a vehicle that is provided with a battery and a motor for driving the vehicle using electric energy, and is equipped with an engine like a general vehicle.

In such a hybrid vehicle, when the power-on upshift is entered, the engagement-side clutch torque is increased while decreasing the release-side clutch torque in the handover section. As such, the output shaft torque is reduced during the handover process will do For this reason, the conventional hybrid vehicle has a problem in that a feeling of deceleration, a feeling of power cut, etc. occur due to a decrease in output shaft torque generated during handover.

The present invention is to solve the problems of the prior art, and to provide an improved vehicle shift control method so that acceleration linearity can be maintained while a handover is in progress when a hybrid vehicle enters a power-on upshift. There is a purpose.

According to a preferred embodiment of the present invention for solving the above problems, there is provided a vehicle shift control method, comprising the steps of: (a) determining whether the vehicle has entered a power-on upshift; (b) when it is determined that the vehicle has entered the power-on upshift, setting a compensation torque for additionally applying to the input shaft so as to constantly maintain the output shaft torque during handover; and (c) increasing the input shaft torque by the compensation torque compared to the starting point input shaft torque at the start time of the handover to perform the handover.

Preferably, in step (b), the compensation torque is set to increase in proportion to a rising speed of the engagement-side clutch torque while the handover is in progress.

Preferably, in the step (b), additionally applying to the input shaft based on a difference between the target engagement-side clutch torque at the end of the handover and the clutch torque at the starting point at the start of the handover The maximum compensation torque is set and performed, and step (c) is performed by increasing the torque of the input shaft by the compensation compensation torque calculated by multiplying the maximum compensation torque by the progress rate of the handover.

Preferably, (d) setting a ratio of a current progress time of the handover to the target progress time of the handover or a ratio of a current torque increase amount to a target torque increase amount of the engagement-side clutch as the progress rate of the handover The method further includes a step, wherein step (c) is performed based on the progress rate of the handover set in step (d).

Preferably, the method comprising: (e) determining whether the vehicle is being driven in any of a charge consumption mode and a charge maintenance mode; (f) determining whether the sum of the starting point input shaft torque and the maximum compensation torque is smaller than the maximum output of the driving motor when the vehicle is being driven in the charge consumption mode; and (g) determining whether the sum of the starting point input shaft torque and the maximum compensation torque is smaller than the sum of the maximum output of the driving motor and the maximum output of the engine when the vehicle is being driven in the charge-holding mode. Further comprising, in step (c), when the vehicle is driven in the charge consumption mode, the sum of the starting point input shaft torque and the maximum compensation torque is smaller than the maximum output of the driving motor, or the vehicle This is performed when the sum of the starting point input shaft torque and the maximum compensation torque is smaller than the sum of the maximum output of the driving motor and the maximum output of the engine while driving in the charge-holding mode.

Preferably, (h) if the sum of the starting point input shaft torque and the maximum compensation torque is equal to or greater than the maximum output of the driving motor, performing the handover while maintaining the torque of the input shaft as the starting point input shaft torque. include

Preferably, (i) if the sum of the starting point input shaft torque and the maximum compensation torque is greater than or equal to the sum of the maximum output of the driving motor and the maximum output of the engine, the hand torque while maintaining the input shaft torque as the starting point input shaft torque It further includes the step of proceeding over.

The present invention relates to a method for controlling a shift in a vehicle, and it is possible to maintain a constant output shaft torque by compensating for a decrease in output shaft torque generated due to an increase in coupling-side clutch torque during handover through an increase in input shaft torque. According to the present invention, it is possible to prevent a feeling of deceleration, a feeling of power cut off due to a decrease in output shaft torque, and the like, and it is possible to maintain acceleration linearity to improve riding comfort and to secure shift consistency and robustness.

1 is a flowchart illustrating a method for controlling a shift of a vehicle according to a preferred embodiment of the present invention;
2 is a diagram showing a schematic configuration of a shift control system of a hybrid vehicle;
3 is a graph illustrating a decrease in torque of an output shaft of a transmission in a handover section;
4 is a graph illustrating a mode in which compensation torque is applied to an input shaft of a transmission.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. In adding reference numerals to the components of each drawing, it should be noted that the same components are given the same reference numerals as much as possible even though they are indicated on different drawings. In addition, in describing the embodiment of the present invention, if it is determined that a detailed description of a related known configuration or function interferes with the understanding of the embodiment of the present invention, the detailed description thereof will be omitted.

In describing the components of the embodiment of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only for distinguishing the elements from other elements, and the essence, order, or order of the elements are not limited by the terms. In addition, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

1 and 2 , in the method for controlling the shift of a vehicle according to a preferred embodiment of the present invention, when the hybrid vehicle enters the power-on upshift, torque of the engagement-side clutch 32 during handover The decrease in the torque (-T _o ) of the output shaft 36 of the transmission 30 due to the increase in (T _y ) is compensated for through the increase in the torque (T _i ) of the input shaft 31, and the transmission during the handover is in progress. The torque (-T _o ) of the output shaft 36 of (30) is provided to keep constant.

First, the controller 40 determines whether the vehicle has entered the power-on upshift (S10).

Next, when it is determined that the vehicle enters the power-on-upshift, the controller 40 sets a compensation torque ΔT _i to be additionally applied to the input shaft 31 while the handover is in progress ( S20 ).

The handover is a shift preparation work in which the engagement side clutch 32 is engaged while releasing the release side clutch 34, and the output (-T _o ω _o ) of the output shaft 36 during this handover is expressed by the following equation equal to 1.

ω _o : output shaft speed

ω _i : input shaft speed

I _i α _i : input shaft inertia

(Δω) _y : Relative speed of the coupling side clutch (= target speed of the input shaft at the rear end of the shift - the speed of the input shaft)

(Δω) _x : Relative speed of the clutch release side (= target speed of the input shaft before the shift - speed of the input shaft)

T _x : Release side clutch torque

In general, during handover, the speed (ω _i ) of the input shaft 31), the torque (T _i ) of the input shaft 31 (hereinafter referred to as ‘input shaft torque (T _i )’), the engagement-side clutch relative speed ( (Δω) _y ) does not change, and the inertia (I _i α _i ) of the input shaft 31 and the release-side clutch relative speed ((Δω) _x ) are zero. Therefore, the above-mentioned Equation 1 can be arranged as Equations 2 to 4 below.

According to Equations 2 and 3, during the handover, the torque (-T _o ) of the output shaft 36 (hereinafter referred to as 'output shaft torque (-T _o )') is the engagement-side clutch torque T _y . It can be seen that the decrease is proportional to the increase. From this, as shown in Equation 5 below, during handover, the input shaft torque (T _i ) is adjusted to be proportional to the rising speed and the rising amount (ΔT _y ) of the engagement-side clutch slip torque (T _y ) at the start time of the handover. By increasing the input shaft torque (T _i ) by a predetermined amount (hereinafter referred to as 'compensation torque (ΔT _i )') compared to the input shaft torque (hereinafter, referred to as 'starting point input shaft torque (T _is )'), the output shaft torque (-T _o ) can be reduced (-ΔT _o ) to keep the output shaft torque (-T _o ) constant.

As shown in FIG. 4 , during the handover, it can be seen that the engagement-side clutch torque T _y is gradually increased from the start time of the handover to the time of the type of the handover. That is, the engagement-side clutch torque T _y is the lowest at the start time of the handover and the highest at the end time of the handover. Hereinafter, the engagement-side clutch torque (T _y ) at the start time of the handover is named as the start-point engagement-side clutch torque (T _ye ), and the engagement-side clutch torque (T _y ) at the end time of the handover is the target engagement The side clutch torque (T _yt ) will be named.

In view of the upward trend of the coupling-side clutch torque (T _y ), the compensation torque (ΔT _i ) should be gradually increased according to the progress rate (β) of the handover from the start point of the handover to the end point of the handover. Able to know. To this end, as shown in Equation 6 below, the controller 40 controls the engagement-side clutch torque T _y corresponding to the difference between the target engagement-side clutch torque T _yt and the starting point engagement-side clutch torque T _y . The maximum compensation torque α proportional to the target torque increase amount ΔT _ymax may be preferentially calculated.

Thereafter, the controller 40 determines in which mode the vehicle is being driven between the charge consumption mode and the charge maintenance mode ( S30 ). The charge consumption mode (CD mode) is a mode that gives priority to EV driving compared to the charge maintenance mode (CS mode). That is, in the charging consumption mode, the vehicle is driven using the output of the driving motor 10 , and in the charging and maintaining mode, the vehicle is driven using both the output of the driving motor 10 and the output of the engine 20 .

Next, when it is determined that the vehicle is being driven in the charge consumption mode, the controller 40 determines that the sum of the starting point input shaft torque T _is and the maximum compensation torque α is less than the maximum output T _max1 of the driving motor 10 . It is determined whether or not it is recognized (S 40).

Thereafter, when it is determined that the sum of the starting point input shaft torque T _is and the maximum compensation torque α is equal to or greater than the maximum output of the driving motor 10 , the controller 40 uses the compensation torque ΔT _i to the output shaft torque Without compensating for the decrease amount (-ΔT ₀ ) of (-T _o ), the handover proceeds in the usual way (S 50). This is, considering that the engine 20 is inevitably turned on during handover if the sum of the starting point input shaft torque T _is and the maximum compensation torque α is equal to or greater than the maximum output of the driving motor 10 , the engine 20 during handover ) to prevent it from turning on.

Next, when it is determined that the vehicle is being driven in the charge holding mode, the controller 40 determines that the sum of the starting point input shaft torque T _is and the maximum compensation torque α is the maximum output of the driving motor 10 and the engine 20 . It is determined whether it is smaller than the sum of the maximum outputs of (S60).

Thereafter, the controller 40 says that the sum of the starting point input shaft torque T _is and the maximum compensation torque α is equal to or greater than the sum of the maximum output of the driving motor 10 and the maximum output of the engine 20 (T _max2 ). If it is determined, the handover is performed in the usual way without compensating for the decrease amount (-ΔT ₀ ) of the output shaft torque (-T ₀ ) using the compensation torque (ΔT _i ) ( S70 ). This is, if the sum of the starting point input shaft torque (T _is ) and the maximum compensation torque (α) is equal to or greater than the sum of the maximum output of the driving motor 10 and the maximum output of the engine 20 (T _max2 ), the starting point input shaft torque during handover ( The compensation torque (ΔT _i ) is constrained so that the sum of T _is ) and the compensation torque (ΔT _i ) is less than or equal to the sum of the maximum output of the driving motor 10 and the maximum output of the engine 20 (T _max2 ). In consideration of the inevitable occurrence of a sense of disparity, this is to prevent the occurrence of such a sense of disparity in shifting during handover.

Next, the controller 40 calculates the handover progress rate β (S80). The method of calculating the handover progress rate β is not particularly limited. For example, as shown in Equations 7 and 8 below, the handover progress rate β ₁ is calculated using the ratio of the handover current progress time to the target handover progress time, or the engagement-side clutch 32 ), the handover progress rate (β ₂ ) can be calculated using the ratio of the current torque increase amount to the target torque increase amount (ΔT _ymax ). It is preferable that the controller 40 determines a smaller value among the handover progress rates β ₁ and β ₂ calculated by the two methods as the handover progress rate β, but is not limited thereto.

Thereafter, the controller 40 multiplies the maximum compensation torque α by the handover progress rate β to calculate the compensation compensation torque α·β to be actually applied to the input shaft 31 , and then the input shaft torque T _i ) is increased by the correction compensation torque (α·β) compared to the starting point input shaft torque (T _is ) to proceed with the handover (S 90). Then, as shown in FIG. 4 , the decrease amount (-ΔT o ) of the output shaft torque (-T _o ) is corrected by _increasing the input shaft torque (T _i ) during handover.

As such, in the method for controlling the shift of a vehicle according to a preferred embodiment of the present invention, a decrease in the output shaft torque (-T _o ) generated due to an increase in the coupling-side clutch torque Ty during handover is reduced by an increase in the input shaft torque (T _i ). It is possible to keep the output shaft torque (-T _o ) constant by compensating for it. According to the shift control method of the vehicle according to the preferred embodiment of the present invention, it is possible to prevent a feeling of deceleration and a feeling of power cut due to a decrease in the output shaft torque (-T _o ) from occurring, and it is possible to prevent the occurrence of a feeling of power cut off and the like, and to maintain the acceleration linearity of the occupant. It is possible to secure shift consistency and robustness while improving riding comfort.

The above description is merely illustrative of the technical spirit of the present invention, and various modifications and variations will be possible without departing from the essential characteristics of the present invention by those skilled in the art to which the present invention pertains.

Therefore, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical spirit of the present invention is not limited by these embodiments. The protection scope of the present invention should be construed by the following claims, and all technical ideas within the equivalent range should be construed as being included in the scope of the present invention.

1: shift control system
10: drive motor
20: engine
30: gearbox
31: input shaft
32: coupling side clutch
34: release side clutch
36: output shaft
40: controller

Claims (7)

(a) determining whether the vehicle has entered the power-on upshift;
(b) when it is determined that the vehicle has entered the power-on upshift, setting a compensation torque for additionally applying to the input shaft so as to constantly maintain the output shaft torque during handover; and
(c) increasing the input shaft torque by the compensation torque compared to the starting point input shaft torque at the start time of the handover to perform the handover. According to claim 1,
Step (b) is,
The compensation torque is set to increase in proportion to a rising speed of the coupling-side clutch torque while the handover is in progress. According to claim 1,
In step (b), the maximum compensation for additionally applying to the input shaft is based on the difference between the target engagement-side clutch torque at the end of the handover and the clutch torque at the starting point at the start of the handover. It is done by setting the torque,
The step (c) is performed by increasing the torque of the input shaft by the corrected compensation torque calculated by multiplying the maximum compensation torque by the progress rate of the handover. 4. The method of claim 3,
(d) setting the ratio of the current progress time of the handover to the target progress time of the handover or the ratio of the current torque increase amount to the target torque increase amount of the engagement-side clutch as the progress rate of the handover including,
The step (c) is performed based on the progress rate of the handover set in the step (d). 4. The method of claim 3,
(e) determining whether the vehicle is being driven in any of a charge consumption mode and a charge maintenance mode;
(f) determining whether the sum of the starting point input shaft torque and the maximum compensation torque is smaller than the maximum output of the driving motor when the vehicle is being driven in the charge consumption mode; and
(g) determining whether the sum of the starting point input shaft torque and the maximum compensation torque is smaller than the sum of the maximum output of the driving motor and the maximum output of the engine when the vehicle is being driven in the charge and maintenance mode; including,
In the step (c), when the vehicle is driven in the charge consumption mode, the sum of the starting point input shaft torque and the maximum compensation torque is smaller than the maximum output of the driving motor, or the vehicle is in the charge maintenance mode and the sum of the starting point input shaft torque and the maximum compensation torque is smaller than the sum of the maximum output of the driving motor and the maximum output of the engine when driving at 6. The method of claim 5,
(h) if the sum of the starting point input shaft torque and the maximum compensation torque is equal to or greater than the maximum output of the driving motor, performing the handover while maintaining the torque of the input shaft as the starting point input shaft torque A vehicle shift control method characterized in that. 6. The method of claim 5,
(i) If the sum of the starting point input shaft torque and the maximum compensation torque is equal to or greater than the sum of the maximum output of the driving motor and the maximum output of the engine, the handover is performed while maintaining the torque of the input shaft as the starting point input shaft torque The shift control method of the vehicle, characterized in that it further comprises the step of:

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