JP2003156134A - Speed change performance simulation device for automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a speed change performance simulation device for an automatic transmission which easily minimizes simulation computation time while securing desired reproducibility by providing an index beforehand when determining a simulation computation period to a set torque slip ratio. SOLUTION: The speed change performance simulation device for the automatic transmission is provided with: a convergence condition determining means of determining a convergence condition of simulation computation as a relationship between a frictional element transmission torque model considering transmission torque of a frictional element as one function to a relative rotational frequency, providing the transmission torque in a minute slip area of a relative rotational frequency set value or lower by a product of the torque slip ratio and the relative rotational frequency and providing the transmission torque in a slip area exceeding the relative rotational frequency set value by torque capacity, the torque slip ratio used in the frictional element transmission torque model, and the simulation computation period; and a simulation computation period setting means of setting the simulation computation period existing in a simulation convergence region by the set torque slip ratio by using the determined convergence condition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technical field of a shift performance simulation device for an automatic transmission, which predicts a motion such as a gear shift shock and estimates a motion at a development stage.

[0002]

2. Description of the Related Art A stepped automatic transmission is now multi-staged from a mainstream forward 4-speed automatic transmission to fifth and sixth speeds in order to improve fuel efficiency, power performance and speed change performance. There is a tendency. Since the multi-stage automatic transmission has a complicated structure, the shift control for that is inevitably complicated. Therefore, further improvement in development efficiency is required.

Therefore, the method of developing an automatic transmission will be described. First, when a new power train such as a planetary gear, a clutch and a brake is determined, this power train is modeled, and a shift shock based on this power train model. Also, the gear shift performance simulation is performed by analyzing the rotation state of each member and the gear shift mechanism, and the motion prediction and motion estimation associated with the gear shift of the automatic transmission are performed.

That is, reducing the development man-hours of the gear shifting performance simulation greatly contributes to the improvement of the development efficiency as it is, and by performing the simulation with high reproducibility by the actual machine, it is possible to predict a defect in advance at the design stage. Therefore, unnecessary design and experiment can be omitted, which also greatly contributes to the improvement of development efficiency.

On the other hand, in the conventional shifting performance simulation method, the relational expression of the torque of each rotating member constituting the power train, the angular acceleration, and the transmission torque of the clutch, brake and one-way clutch is used as a motion equation. Describe. To this, the angular acceleration relational expression of each rotating member of the planetary gear is added and described as a determinant. Then, an inverse matrix is created from the determinant, and the angular velocity of each rotating member is calculated according to the input torque and the transmission torque of the clutch, brake, and one-way clutch.

In this simulation calculation, the transmission torque of the friction element (hereinafter, generically referred to as the clutch) that is engaged by the hydraulic pressure applied to the clutch or the brake is treated as a known parameter, but the clutch is in the engaged state. Since the transmission torque at and the transmission torque at the slip state are different, it was necessary to separate the cases in order to solve the equation of motion.

That is, as shown in FIG. 11, the clutch transmission torque Ttrans in the engaged state in which the clutch relative rotational speed Δω is zero is equal to or less than the clutch torque capacity Tclutch, so Ttrans = Tclutch input (input torque). However, since the clutch transmission torque Ttrans in the slipping state in which the clutch relative speed Δω is generated exceeds the clutch torque capacity Tclutch, the input torque Tclutch i
Ttrans = Tclutch (clutch torque capacity) regardless of the size of nput. As described above, there is a problem that it is necessary to solve the equation of motion by dividing into two cases, and it takes a lot of man-hours to create the power train model.

Therefore, the clutch transmission torque Ttrans is
A function of the clutch relative rotational speed Δω, that is, a system in which a torque capacity is generated due to the presence of a slight slip has been proposed. In this system, as shown in FIG. 12, the clutch transmission torque Ttrans in a minute slip range equal to or less than the clutch relative rotational speed setting value Δω slip is given by the product of the torque slip ratio κ and the clutch relative rotational speed Δω, The clutch transmission torque Ttrans in the slip range exceeding the relative rotational speed setting value Δω slip is given by Ttrans = Tclutch.
That is, the clutch transmission torque Ttrans is obtained by the following formula. Ttrans = min (Tclutch, κ · Δω) In this case, when applying the clutch transmission torque Ttrans, it is not necessary to distinguish between the engaged state and the slipping state, and continuous handling is possible.

[0009]

However, when the clutch transmission torque Ttrans is continuously given by the above equation, the torque slip ratio κ becomes a very important parameter, and as shown in FIG. 13 (a). , If the value of this torque slip ratio κ is too small, this clutch will converge (engage) with a large value of the relative rotational speed Δω, so when studying the gear ratio, etc. A large error occurs between the two, resulting in a simulation with low reproducibility.

Further, as shown in FIG. 13 (b), when the value of the torque slip ratio κ is too large, the characteristics are close to those in FIG. 11, and the error between the simulation data and the actual machine data is small (reproducibility). However, if the clutch relative rotation speed Δω approaches zero, if the simulation calculation period Δt is set to a relatively long period so that the simulation calculation time can be suppressed in a short time, Δω = The positive and negative values of the clutch transmission torque Ttrans are repeated before and after 0, and the simulation calculation diverges. That is, in order to converge the simulation calculation when the value of the torque slip ratio κ is set large, it is necessary to set the simulation calculation cycle Δt to a very short cycle.

On the other hand, with respect to the setting of the torque slip ratio κ and the simulation calculation period Δt, only empirical values (tries & errors) have been used so far. When the value of the torque slip ratio κ is set to a large value in order to obtain reproducibility, the simulation calculation cycle Δt is shortened more than necessary in order to avoid divergence of the simulation calculation. For this reason, the simulation calculation time has become long.

The present invention has been made by paying attention to the above problems, and an object thereof is to give a desired index by giving an index in advance when determining a simulation calculation cycle for a set torque slip ratio. While ensuring reproducibility,
An object of the present invention is to provide a shift performance simulation device for an automatic transmission, which can easily minimize the simulation calculation time.

[0013]

In order to achieve the above-mentioned object, in the invention according to claim 1, the transmission torque of the friction element, which is a known parameter, with respect to the power train model of the automatic transmission expressed by the equation of motion. A simulation for calculating the angular velocity of each rotating member, the gear transmission torque, etc., which are unknown parameters, is performed by inputting and calculating etc., and based on the result of this simulation, the operation prediction related to the shift of the automatic transmission is performed. In a gear shifting performance simulation device for an automatic transmission, the transmission torque of a friction element is taken as a function of the relative rotation speed, and the transmission torque in a minute slip region equal to or less than a relative rotation speed set value is compared with a torque slip ratio and a relative rotation speed. Friction element transmission, which is given by the product and gives the transmission torque by the torque capacity in the slip region that exceeds the relative rotation speed setting value. And Rukumoderu, wherein the friction element transmits torque model torque slip ratio used, and the convergence condition determining means for simulation calculation as the relationship to determine the condition of convergence between the simulation calculation period,
Using the convergence condition determined by the convergence condition determining means,
And a simulation calculation cycle setting means for setting a simulation calculation cycle existing in the simulation convergence region with the set torque slip ratio.

According to a second aspect of the present invention, in the shift performance simulation device for an automatic transmission according to the first aspect, the convergence condition determining means has the following formula | 1- (κ / I) · Δt | < 1 where κ is the torque slip ratio, I is the inertia, and Δt is the simulation calculation cycle. Is a means for determining the convergence condition represented by.

According to a third aspect of the present invention, in the shift performance simulation device for an automatic transmission according to the first or second aspect, the simulation calculation cycle setting means sets the slip amount of the friction element allowed in the actual machine. The relative rotation speed is set, and the torque slip ratio is set by using a friction element transmission torque model.

According to a fourth aspect of the present invention, in the shift performance simulation device for an automatic transmission according to any one of the first to third aspects, the simulation calculation cycle setting means sets the torque slip ratio and the convergence condition. Is a means for determining the simulation calculation cycle as a boundary value between divergence and convergence, and setting the simulation calculation cycle by shortening the simulation calculation cycle.

According to a fifth aspect of the invention, in the shift performance simulation device for an automatic transmission according to the fourth aspect, a data deviation amount for calculating a data deviation amount between the simulation data obtained by performing the simulation and the actual machine data. The calculation means is provided, and the simulation calculation cycle setting means is means for further shortening the set simulation calculation cycle when the data deviation amount exceeds the allowable deviation amount.

According to a sixth aspect of the present invention, in the shift performance simulation device for an automatic transmission according to any one of the first to fifth aspects, the power train model of the automatic transmission has a large number of general-purpose numerical analysis functions. It is a feature created by using the software "MATLAB" that it has.

[0019]

In the invention according to claim 1, in the friction element transmission torque model, the transmission torque of the friction element is a function of the relative rotation speed, and is a minute value equal to or less than the relative rotation speed set value. The transmission torque in the slip region is given by the product of the torque slip ratio and the relative rotation speed, and the transmission torque in the slip region exceeding the relative rotation speed set value is given by the torque capacity. Then, the convergence condition determining means determines a condition for the simulation calculation to converge as a relationship between the torque slip ratio used in the friction element transfer torque model and the simulation calculation cycle, and the simulation calculation cycle setting means determines the convergence condition. Using the convergence condition determined by the means, the simulation calculation period existing in the simulation convergence region is set with the set torque slip ratio.

In other words, by adopting a model in which the friction element is always slightly slipping even during complete engagement as the friction element transmission torque model, the transmission torque of the friction element can be obtained in the cases of engagement and slippage. It can be handled continuously without doing. Moreover, in the past, with respect to the setting of the value of the torque slip ratio and the simulation calculation cycle, conventionally, the empirical value (trie & error) was used.
As the relationship between the torque slip ratio and the simulation calculation cycle, the convergence condition for convergence of the simulation calculation is used, and the simulation calculation cycle is set. Therefore, for example, even if the value of the torque slip ratio is set to a large value in order to obtain good reproducibility, without shortening the simulation calculation period more than necessary,
The optimum simulation calculation cycle can be easily set. As a result, the simulation calculation time can be set to the minimum necessary calculation time in which the simulation calculation does not diverge.

Therefore, by giving an index (convergence condition) in advance when deciding the simulation calculation cycle for the set torque slip ratio, while ensuring desired reproducibility,
The simulation calculation time can be easily minimized.

In the invention according to claim 2, in the convergence condition determining means, the following equation | 1- (κ / I) · Δt | <1κ: torque slip ratio, I: inertia, Δt: The convergence condition represented by the simulation calculation cycle is determined.

This equation is a condition of the torque-slip ratio κ that does not diverge calculated by using Euler's method integration for the one-degree-of-freedom friction element model. The torque-slip ratio κ and the simulation calculation period Δt can be calculated by a simple equation. A convergence condition between and can be given.

In the invention according to claim 3, in the simulation calculation cycle setting means, the slip amount of the friction element allowed in the actual machine is set as the relative rotation speed set value, and the torque slip is calculated using the friction element transmission torque model. The ratio is set.

Therefore, by setting the slip amount of the friction element allowed in the actual machine as the relative rotation speed setting value, the torque slip ratio becomes the largest value among the appropriate values, and a highly reproducible simulation can be performed. it can.

In the invention according to claim 4, in the simulation calculation cycle setting means, the simulation calculation cycle as a boundary value between divergence and convergence is determined by the set torque slip ratio and the convergence condition, and this simulation calculation cycle is set. The simulation calculation cycle is set by shortening.

Therefore, it is possible to set the simulation calculation period slightly within the convergence region from the boundary value of divergence and convergence, and the simulation calculation time is set to the shortest time by the longest simulation calculation period at which the simulation calculation converges. Can be set to.

In the invention according to claim 5, the data deviation amount calculating means calculates the data deviation amount between the simulation data obtained by performing the simulation and the actual machine data, and the simulation calculation cycle setting means calculates the data deviation amount. When the deviation amount exceeds the allowable deviation amount, the set simulation calculation cycle is further shortened.

Therefore, even if the simulation calculation diverges due to factors other than the factors considered in the convergence condition, the simulation can be performed until the data deviation amount becomes equal to or less than the allowable deviation amount by the further shortened simulation calculation period. The simulation calculation time can be set to the shortest time by the longest simulation calculation cycle in which the simulation calculation converges.

In the invention according to claim 6, the power train model of the automatic transmission is created by using "MATLAB" which is software having a large number of general-purpose numerical analysis functions.

That is, conventionally, the programming itself such as power train model creation was performed using the language such as Fortran, so that the developer also had to create the basic function in the program. Therefore, the program became complicated and it was difficult for anyone other than the creator to understand, and it was necessary to prepare a detailed manual for standardization.

On the other hand, "MATLAB (MATLA)
B) ”can greatly improve programming work such as model creation, and can be easily understood by visualizing and standardizing the model.

[0033]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment for realizing a shift performance simulation device for an automatic transmission according to the present invention will be described based on a first embodiment corresponding to the inventions according to claims 1 to 6. .

(First Embodiment) First, the structure will be described. FIG. 1 is a skeleton diagram showing a power train of an automatic transmission to be modeled by the gear shifting performance simulation apparatus of the first embodiment. In FIG. 1, INPUT is an input shaft and OUT.
PUT is output shaft, TC is transmission case, FP
Is front planetary gear, MP is mid planetary gear, RP is rear planetary gear, F / B is front brake, I / C is input clutch, D / C is direct clutch, H & LR / C is high & low reverse clutch. , R / B
Is reverse brake, FWD / B is forward brake, LC /
B is low coast brake, 1st OWC is 1st speed one-way clutch, FWDOWC is forward one-way clutch, 3rdO
WC is a 3-speed one-way clutch, M1 is the first rotating member,
M2 is a second rotating member, M3 is a third rotating member, M4 is a fourth rotating member, M5 is a fifth rotating member, M6 is a sixth rotating member, M7 is a seventh rotating member, and M8 is an eighth rotating member. .

The front brake F / B fixes the front sun gear. The input clutch I / C connects the input shaft INPUT, the mid ring gear and the front ring gear. The direct clutch D / C connects the rear carrier and the rear sun gear. The high & low reverse clutch H & LR / C connects the mid sun gear and the rear sun gear.

The reverse brake R / B fixes the rear carrier. The forward brake FWD / B fixes the mid sun gear. The low coast brake LC / B
Fix the mid sun gear.

The first-speed one-way clutch 1st OWC frees rotation of the rear sun gear in the forward rotation direction with respect to the mid sun gear, and fixes the reverse rotation. The forward one-way clutch FWD OWC frees the rotation of the mid sun gear in the forward rotation direction and fixes the reverse rotation. 3rd one-way clutch 3r
dOWC is free to rotate the front sun gear in the forward direction,
Fix the reversal.

FIG. 2 is a diagram showing a speed change element operation table of the automatic transmission shown in FIG. 1. By operating each speed change element as shown in FIG. 2, an automatic speed change of 5 forward speeds and a reverse speed 1 speed are obtained. I am trying. That is, for the automatic transmission to be modeled, a skeleton, which is expected to be small and lightweight, can be selected, and three sets of single planetary gears can achieve high gear train efficiency, and "running" It is possible to select a gear ratio that is suitable for pursuing. In addition, by devising the arrangement of the seven clutches and brakes, the three one-way clutches can be efficiently arranged, and the shift performance can be improved at the same time.

FIG. 3 shows a general-purpose numerical analysis program "MATL".
It is a block diagram which shows the example which programmed the power train model using "AB".

In FIG. 3, 1 is a running resistance model, 2 is an engine & torque converter model, 3 is a clutch model, 4 is a power train model, 5 is a member rotational speed output unit, 6 is a vehicle model, 7 is a vehicle, and 8 is a vehicle. , 9 are terminators.

The running resistance model 1 has an absolute vehicle speed value | Vs
The running resistance torque Ts is calculated based on p | and input to the power train model 4.

Engine and torque converter model 2
Calculates the turbine torque Tt based on the throttle opening Tvo and the vehicle speed Vsp and inputs it to the power train model 4.

The clutch model 3 has front brake torque TFB, direct clutch torque TDC, input clutch torque TIC, high & low river based on each member rotation speed ω1 to ω8 and a fastening pressure given by a hydraulic model 10 which will be described later. Scratch torque THLRC, forward brake torque TFWDB, reverse brake torque TRB, low coast brake torque TLCB, third speed one-way clutch torque T3rdOWC, first speed one-way clutch torque T1stOWC, forward one-way clutch torque TFOWC are calculated and input to the power train model 4. .

The power train model 4 includes the torques TFB, TDC, TIC, THLRC, TFW from the clutch model 3.
DB, TRB, TLCB, T3rdOWC, T1stOWC, TFOWC are input, and based on these input torque information, the member rotation speed ω1 of the first rotation member M1, the member rotation speed ω2 of the second rotation member M2, and the third rotation member. M3 member speed ω
3, member rotation speed ω4 of the fourth rotation member M4, member rotation speed ω5 of the fifth rotation member M5, member rotation speed ω6 of the sixth rotation member M6, member rotation speed ω7 of the seventh rotation member M7, eighth rotation member The member rotation speed ω8 of M8 is calculated, and each member rotation speed ω1 to ω8 is calculated as the member rotation speed output unit 5
Output to. Also, the front ring gear transmission torque T1
And rear ring gear transmission torque T3 are calculated and output to the terminators 8 and 9, respectively. Further, the mid ring gear transmission torque T2 is calculated and output to the vehicle model 6.
The power train model 4'is shown by the Matlab expression of the equation (3) described later.
In this power train model 4 ′, K represents an inverse matrix.

The vehicle model 6 inputs the mid ring gear transmission torque T2 from the power train model 4 and estimates the longitudinal acceleration G, the vehicle speed Vsp and the torque Td of the vehicle 7.

FIG. 4 is a diagram showing the hydraulic model 10, which includes front brake pressure PFB, input clutch pressure PIC, high &
Low reverse clutch pressure PHLRC, reverse brake pressure P
RB, direct clutch pressure PDC, low coast brake pressure PLCB, forward brake pressure PFWDB, line pressure PL
Are produced according to the hydraulic characteristics determined by the time axis.

Next, the operation will be described.

[Formulation of Power Train Model] The equations of motion for each of the rotating members M1 to M8 are set and expressed as a matrix as follows.・ Torque relational expressions ((1) to (8))

[Formula 1] ・ Planetary gear relational expressions ((19) to (11))

[Formula 2] ・ Equation (1) to (8) of modified equation (1), the left side is the term including unknown parameters (angular acceleration of each rotating member, ring gear transmission torque), and the right side is the known parameter (clutch). The equation is modified as a term of only transmission torque, brake transmission torque, OWC transmission torque, turbine torque, and running resistance torque.

If this is expressed by a determinant,
It becomes like the formula (3).

[Formula 3] Therefore, from the above equation (3), the angular acceleration of each rotating member,
The ring gear transmission torques T1, T2, T3 can be calculated.
The member velocities ω1 to ω8 of each rotating member are calculated by integrating the angular acceleration of each rotating member.

[Clutch Transmission Torque Model] The clutch transmission torque Ttrans is a function of the clutch relative rotational speed Δω,
In other words, we adopted a method in which torque capacity is generated due to the presence of slight slippage.

In this system, as shown in FIG. 12, the clutch transmission torque Ttrans in a minute slip range equal to or less than the clutch relative rotational speed setting value Δω slip is calculated by multiplying the torque slip ratio κ by the clutch relative rotational speed Δω. The clutch transmission torque Ttrans in the slip range that exceeds the clutch relative rotation speed setting value Δω slip is given by Ttrans = Tclutch. That is, the clutch transmission torque Ttran is calculated by the following formula.
s is calculated (friction element transfer torque model). Ttrans = min (Tclutch, κ · Δω) (4) In this case, when applying the clutch transmission torque Ttrans, it is not necessary to distinguish between the engaged state and the slipping state, and continuous handling is possible.

[Concept of model (function)] In this simulation, the torque slip ratio κ representing "torque / slip amount" is a very important parameter.

That is, when the inclination of the torque slip ratio κ is too small, this clutch converges (engages) at a large value of the relative rotation speed, and as a result, a large error occurs when the gear ratio is examined ( FIG. 13 (a)). Conversely, if the inclination of the torque slip ratio κ is made too large, the simulation calculation will diverge (FIG. 13 (b)).

This time, in constructing the simulation, the conditions of the torque slip ratio κ at which divergence does not occur are obtained so that the future torque slip ratio κ can be easily set. That is, the condition of the torque-slip ratio κ that does not diverge when the Euler method integration is used for the one-degree-of-freedom clutch model is shown in Expression (9). The calculation flow is shown in FIG. 5, and the one-degree-of-freedom clutch model is shown in FIG.

The torque balance of the clutch model shown in FIG.

[Formula 4] Becomes Equation (5) is the condition of ω ≒ 0,

[Formula 5] Discretizing equation (6),

[Formula 6] From the equation (7), the relationship between the n and the n-1th ω is

[Formula 7] The condition for the right side of equation (8) to converge is equation (9).

[Formula 8] This equation (9) is shown in the graph of FIG. 7 with the vertical axis representing the torque slip ratio κ and the horizontal axis representing the simulation calculation period Δt. That is, Δt which is a modification of equation (9)
= 2I / κ as the boundary line, and Δt> 2
The hatched area of I / κ diverges, Δt <2I / κ
This means that the region of is a convergence, and when the torque slip ratio κ is set to a certain value, the simulation calculation period Δt existing in the convergence region can be determined (convergence condition determining means).

[Simulation Calculation Processing] FIG. 8 is a flowchart showing the flow of the simulation calculation processing executed by the computer. Each step will be described below.

In step S1, a mathematical expression of the modeling target (power train of the automatic transmission) is performed. Specifically, 1) Variable setting of rotating member to model power train 2) Creation of relational expression of torque (Equation (1) above) 3) Creation of relational expression of rotation basic equation of planetary gear (Equation (2) above) ) 4) Expressing 1) to 3) in a matrix (Equation (3) above) In step S2, the relation of the determinant expressed in step S1 is "MATLAB" having a large number of general-purpose numerical analysis functions.
To enter.

At step S3, the output shaft angular velocity error Δ which is the difference between the theoretical output shaft angular velocity value and the actual output shaft angular velocity value.
Calculate ω '. Here, the theoretical value of the output shaft angular velocity is a value with respect to the input shaft angular velocity when the clutch / brake does not slip at each shift stage, and the actual output shaft angular velocity value is the clutch / brake at each shift stage. This is the value for the input shaft angular velocity when it is assumed that the actual amount of slip is allowed.

In step S4, the output shaft angular velocity error Δω 'is assigned to each of the plurality of clutches / brakes to be engaged at that gear, and the assigned value (slip of the friction element allowed by the actual machine is used). Amount) as the clutch relative rotation speed setting value Δω slip, and the torque slip ratio κ is set based on the clutch relative rotation speed setting value Δω slip and the Ttrans-Δω characteristic shown in FIG.

In step S5, the set torque slip ratio κ, the inertia I which is a known value, and Δt = 2I / κ, which is an expression representing the boundary line in FIG. 7, are used as a boundary period. The simulation calculation period Δt is determined.

In step S6, the simulation calculation period Δt 'is set to a value on the convergence side of the simulation calculation period Δt. For example, the calculation formula Δt ′ = Δt−α is used.

In step S7, the set simulation calculation period Δt 'and the torque slip ratio κ are set to "MATL".
The simulation is carried out by inputting to "AB" and performing calculation.

In step S8, the simulation data is compared with the actual machine data to calculate the data deviation amount between the simulation data and the actual machine data (data deviation amount calculating means).

In step S9, it is determined whether the data deviation amount calculated in step S8 is less than or equal to the allowable deviation amount,
If the data deviation amount exceeds the allowable deviation amount, step S1
If the data deviation amount is equal to or less than the allowable deviation amount, the process proceeds to step S11.

In step S10, since the data deviation amount exceeds the permissible deviation amount, it is considered that the simulation calculation has diverged due to another unexpected factor, and the simulation calculation is performed so that the simulation calculation tends to converge. The period Δt 'is shortened (corresponding to the simulation calculation period setting means in claim 5). For example, Δt '(n) =
A calculation formula of Δt ′ (n−1) −β is used. Note that Δt '(n)
Is a new simulation calculation period, and Δt '(n-1) is a simulation calculation period up to now.

In step S11, based on the results up to step S9, the estimated result of the operation prediction of the automatic transmission is continuously output in "MATLAB". (Specific example of estimation result output) 1) Gear shift mechanism estimation result 2) Gear shift shock simulation estimation result In this flowchart, steps SS3 to S6.
Corresponds to the simulation calculation cycle setting means in claims 1 to 4.

[Simulation Example] FIG. 9 is a diagram showing the results of gear shift shock simulation estimation in the 1-2 upshift using this simulation model. Figure 9
The solid line in (a) is a simulation data characteristic diagram of vehicle acceleration at 1-2 upshift, and the dotted line in FIG. 9 (a) is 1
2 is a characteristic diagram of actual vehicle data of vehicle acceleration at the time of upshifting, and FIG. 9B is a characteristic diagram of direct clutch pressure.

As is clear from FIG. 9 (a), it is found that the simulation data of the vehicle acceleration and the actual machine data have a high degree of agreement.
It is possible to perform a shift shock simulation with two upshifts with high reproducibility.

Next, at the design stage, a failure is predicted in advance,
We will introduce examples of measures taken. FIG. 10 is a diagram showing a shift shock simulation estimation result in a 5-2 downshift using this simulation model. Figure 10
(a) is a rotational speed characteristic diagram and vehicle acceleration characteristic diagram of each rotating member when imbalanced oil pressure is applied to each clutch / brake, and FIG. 10 (b) shows a balanced oil pressure to each clutch / brake. FIG. 6 is a rotational speed characteristic diagram and a vehicle acceleration characteristic diagram of each rotating member when applied.

5-2 Downshift is performed by a plurality of clutches.
Since the brake is released and engaged, it is difficult to design the optimum control unit by conventional design study, and it is necessary to repeat the experiment. On the other hand, in this simulation, as shown in FIG.
When the release timing of the low reverse clutch H & LR / C is delayed, it was found that a projection-like acceleration change (whisker-like shock) occurs during shifting.

This simulation model is effective for the mechanism analysis of the shift because the calculation result includes the rotational speed and the transmission torque of each part. By analyzing these parameters, the cause of the aforementioned acceleration change was extracted. This result was fed back to the design to use the controller as the optimal solution (Fig. 10 (b)) for the progress of the shift, which accelerates the release timing of the high & low reverse clutch H & LR / C, to prevent problems.

Next, the effect will be described.

(1) The clutch transmission torque Ttrans is set as a function of the clutch relative rotation speed Δω, and the clutch transmission torque Ttrans in the minute slip range equal to or less than the clutch relative rotation speed set value Δωslip is calculated as the torque slip ratio κ and the clutch. The clutch transmission torque Ttrans in the slip range exceeding the clutch relative rotation speed setting value Δωslip is given by the clutch torque capacity Tcluch.
As a relationship between the torque slip ratio κ and the simulation calculation period Δt, a condition for the simulation calculation to converge is determined, and the determined convergence condition is used, and the simulation calculation period Δ existing in the simulation convergence region at the set torque slip ratio κ. Since t is set, an index (convergence condition) is given in advance when determining the simulation calculation cycle Δt for the set torque slip ratio κ, so that the simulation calculation can be easily performed while ensuring desired reproducibility. The time can be minimized.

(2) The convergence condition is │1- (κ / I) Δt
Since it is given by the formula represented by | <1,
A simple condition can give a convergence condition between the torque slip ratio κ and the simulation calculation period Δt.

(3) Let the clutch / brake slip amount allowed in the actual machine be the clutch relative rotation speed set value Δωslip, and
Since the torque slip ratio κ is set using trans = min (Tclutch, κ · Δω), the torque slip ratio κ becomes the largest value among the proper values, and a highly reproducible simulation should be performed. You can

(4) Set torque slip ratio κ and | 1-
(Κ / I) · Δt | = 1 determines the simulation calculation period Δt as a boundary value between divergence and convergence, and shortens the simulation calculation period Δt to perform the simulation calculation. '
Since (<Δt) is set, it is possible to set the simulation calculation period Δt 'slightly within the convergence range from the boundary value of divergence and convergence, and the longest simulation in which this simulation calculation converges. The simulation calculation time can be set to the shortest time by the calculation cycle Δt ′.

(5) The data deviation amount between the simulation data obtained by executing the simulation and the actual machine data is calculated, and when the data deviation amount exceeds the allowable deviation amount, the set simulation calculation period Δt ' Even if the simulation calculation diverges due to factors other than the factors considered in the setting of the convergence condition, the simulation calculation time can be reduced by the longest simulation calculation period Δt 'at which the simulation calculation converges. It can be set in the shortest time.

(6) The power train model of the automatic transmission is the software "MAT" which has a large number of general-purpose numerical analysis functions.
Since it is created by using "LAB", programming work such as model creation can be made significantly efficient, and anyone can easily understand it by visualizing or standardizing the model.

(Other Embodiments) The shift performance simulating apparatus for an automatic transmission according to the present invention has been described above based on the first embodiment. However, the specific configuration is not limited to this first embodiment. Rather, changes and additions to the design are allowed without departing from the gist of the invention according to each claim of the claims.

[Brief description of drawings]

FIG. 1 is a skeleton diagram showing a power train of an automatic transmission to be modeled by a gear shifting performance simulation device according to a first embodiment.

FIG. 2 is a diagram showing a shift element operation table of the automatic transmission shown in FIG.

FIG. 3 is a block diagram showing an example in which the power train model of the automatic transmission shown in FIG. 1 is programmed by using a general-purpose numerical analysis program “MATLAB”.

4 is a diagram showing a hydraulic model of the automatic transmission shown in FIG.

FIG. 5 is a block diagram showing a calculation flow of a condition of a torque slip ratio κ that does not diverge when the Euler method integration is used.

FIG. 6 is a diagram showing a one-degree-of-freedom clutch model.

FIG. 7 is a convergence condition characteristic diagram showing boundary conditions of convergence and divergence between the torque slip ratio κ of clutch transmission torque and the simulation period Δt.

FIG. 8 is a flowchart showing a flow of a simulation calculation process executed by a computer.

FIG. 9 is a diagram showing a shift shock simulation estimation result in a 1-2 upshift using this simulation model.

FIG. 10 is a diagram showing a shift shock simulation estimation result in a 5-2 downshift using this simulation model.

FIG. 11 is a diagram showing a clutch transmission torque model which is divided into cases of engagement and slippage.

FIG. 12 is a diagram showing a clutch transmission torque model expressed as a function of clutch relative rotation speed.

13 is a diagram showing a clutch transmission torque model when the torque slip ratio is too small and when the torque slip ratio is too large in the clutch transmission torque model shown in FIG.

[Explanation of symbols]

1 Running resistance model 2 Engine & torque converter model 3 clutch model 4 power train model 5 Member rotation speed output section 6 Vehicle model 7 vehicles 8, 9 terminator 10 Hydraulic model

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazuhito Sano             No. 1-1 Yoshiwara Takaracho, Fuji City, Shizuoka Prefecture             Co-Trans Technology Co., Ltd. (72) Inventor Kazuo Tomioka             No. 1-1 Yoshiwara Takaracho, Fuji City, Shizuoka Prefecture             Co-Trans Technology Co., Ltd. F-term (reference) 3J552 MA03 NA01 PA02 PA54 RA02                       SA07 SA13 SA18 SA52                 5B046 AA04 JA07

Claims (6)

[Claims] 1. A power train model of an automatic transmission expressed by a motion equation is input by a transmission torque of a friction element, which is a known parameter, and is calculated.
A simulation is performed to calculate the angular velocity and gear transmission torque of each rotating member, which is an unknown parameter, and based on this simulation result, in the shift performance simulation device of the automatic transmission that predicts the operation related to the shift of the automatic transmission, The transmission torque of the friction element is taken as a function of the relative rotation speed, and the transmission torque in the minute slip range below the relative rotation speed setting value is given by the product of the torque slip ratio and the relative rotation speed. A friction element transfer torque model that gives a transfer torque in a slip range exceeding the torque capacity, a torque slip ratio used in the friction element transfer torque model, and a condition for the simulation calculation to converge as a relationship between the simulation calculation cycle are determined. And the convergence condition determining means for determining Using the convergence conditions,
A shift performance simulation device for an automatic transmission, comprising: a simulation calculation period setting means for setting a simulation calculation period existing in a simulation convergence region with a set torque slip ratio. 2. The shift performance simulation device for an automatic transmission according to claim 1, wherein the convergence condition determining means has the following equation | 1- (κ / I) · Δt | <1, where κ is torque. The slip ratio, I is the inertia, and Δt is the simulation calculation period. A shift performance simulation device for an automatic transmission, which is means for determining a convergence condition represented by 3. The shift performance simulation device for an automatic transmission according to claim 1 or 2, wherein the simulation calculation cycle setting means sets a slip amount of a friction element allowed in an actual machine as a relative rotation speed set value. A shift performance simulation device for an automatic transmission, characterized in that it is means for setting a torque slip ratio using a friction element transmission torque model. 4. The shift performance simulation device for an automatic transmission according to claim 1, wherein the simulation calculation cycle setting means sets a boundary between divergence and convergence according to the set torque slip ratio and convergence condition. A shift performance simulation device for an automatic transmission, characterized in that it is means for determining a simulation calculation cycle as a value and setting the simulation calculation cycle by shortening the simulation calculation cycle. 5. The shift performance simulation device for an automatic transmission according to claim 4, further comprising data deviation amount calculation means for calculating a data deviation amount between the simulation data obtained by performing the simulation and the actual device data, The shift performance simulation apparatus for an automatic transmission, wherein the simulation calculation cycle setting means is means for further shortening the set simulation calculation cycle when the data deviation amount exceeds the allowable deviation amount. 6. The shift performance simulation device for an automatic transmission according to claim 1, wherein the power train model of the automatic transmission is software having a large number of general-purpose numerical analysis functions. (MATLA
B) ”is used to create a shift performance simulation device for an automatic transmission.