JP3449229B2 - System control unit - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system control device for performing feedback control on, for example, a belt type continuously variable transmission.

[0002]

2. Description of the Related Art Conventionally, a belt type continuously variable transmission (CVT) has been known as a continuously variable transmission for vehicles. The control device for controlling this belt type continuously variable transmission controls the gear ratio of the continuously variable transmission to the operating condition of the vehicle by controlling the pulley position and the primary rotation speed (the rotation speed of the drive pulley). It controlled so that it might become a gear ratio.

In order to adjust the gear ratio, the belt type continuously variable transmission has a secondary hydraulic pressure control system for setting a secondary hydraulic pressure (hydraulic pressure for adjusting the belt holding force of the driven pulley) according to the input torque. , And a gear ratio control system that sets a primary oil pressure (oil pressure for adjusting the pulley position of the drive pulley) necessary to obtain a predetermined gear ratio according to the input torque and the secondary oil pressure.

Then, in the gear ratio control system, in order to realize the target gear ratio, the corresponding target primary pulley position (target pulley position) or target primary rotational speed is calculated, and the actual value of these pulley position or primary rotational speed is calculated. The target primary hydraulic pressure for feedback control is calculated based on the deviation between the and, and the actual hydraulic pressure is adjusted by controlling the valves and the like so as to reach this target primary hydraulic pressure.

[0005]

However, in the feedback control described above, when setting the target primary hydraulic pressure which is the control instruction value, the target primary hydraulic pressure is set to a predetermined value from the viewpoint of the structure of the continuously variable transmission and the safety of control. The target primary hydraulic pressure was sometimes limited to prevent deviation from the range.

By applying this limiter, the target primary hydraulic pressure is set within a predetermined range, which is advantageous in improving safety and the like, but another problem may occur. For example, as shown in FIG. 16, in the conventional case, when the target primary oil pressure is set as indicated by the line a at the time of transition, the limiter of the line b is applied, so that the target primary oil pressure cannot be greatly reduced. It was Therefore, the actual primary hydraulic pressure is in a state where the pressure reduction is small as shown by the line c, and the desired primary hydraulic pressure as shown by the line d cannot be realized, and there is a problem in control followability.

As a countermeasure against this, even if an attempt is made to advance the phase by a large amount (with respect to the target primary hydraulic pressure) as indicated by the line e, the limiter is applied early and the line e does not actually go below the line b. Therefore, the actual primary hydraulic pressure with less pressure reduction as shown by the line f cannot be realized, and the desired primary hydraulic pressure on the line d cannot be realized, and the followability is not improved so much.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a system controller having excellent control followability.

[0009]

Means for Solving the Problems and Effects of the Invention

(1) According to the invention of claim 1, a control instruction value for bringing an actual value of a controlled object close to a target value is calculated from a deviation between the target value and the actual value, and an actuator is driven based on the control instruction value. Thus, in a system control device that performs feedback control, a limiter processing unit that applies a limiter set in consideration of the characteristics of the control target to the control instruction value, and compensation that compensates for a transient operation in the control instruction value. Regarding the item, the gist is a system control device including a limiter limiting unit that limits the process of applying the limiter.

Conventionally, a control target (for example, continuously variable transmission)
From the viewpoint of the structure and safety of control, a control instruction value (for example, target primary hydraulic pressure) for bringing an actual value (for example, actual pulley position or actual primary rotation speed) close to a target value (target pulley position or target primary rotation speed) In some cases, a limiter may be applied, that is, the control instruction value may be limited to a predetermined range. However, when this limiter is applied, the response (following property) during transient may be deteriorated.

Therefore, in the present invention, with respect to the compensation term for compensating the transient operation of the control instruction value, the process of applying the limiter is limited (for example, prohibited). As a result, when feedback control is performed, the function of the compensation term for compensating for the transient operation when setting the control instruction value is not impaired, so a sufficiently transient operation (that is, an operation that quickly responds to changes) is performed. ) Can be done.

That is, in the present invention, the actuator is driven based on the control instruction value including the control term for compensating for the transient operation, so that the actual value can be made to quickly follow the target value. As a result, there is an effect that the followability during the transition is improved. (2) The invention of claim 2 is a dynamic component filter (for example, a high-pass filter) that passes only a signal that indicates a transient operation, and a static component filter (for example, a high-pass filter) that passes only a signal that indicates a steady operation. The system controller according to claim 1, further comprising: a low-pass filter) for performing the process of applying the limiter to the output from the static component filter.

The present invention exemplifies the invention according to claim 1, wherein, for example, a limiter is applied to the output of the low-pass filter. Therefore, as illustrated in FIG. 1, for example, by a high-pass filter,
Of the outputs of the feedback calculation unit (which calculates the output that reduces the deviation), only the high-frequency component that enhances the transient response is output to the actuator, so that the followability during transient is improved.

On the other hand, for example, the low-frequency component of the output of the low-pass filter, that is, the output of the feedback calculation unit is
Since it is limited by the limiter processing unit, safety is secured. As a result, the remarkable effect that the followability can be improved while ensuring necessary safety and the like is achieved.

(3) According to a third aspect of the present invention, a control instruction value that brings the actual value of the controlled object close to the target value is calculated from the deviation between the target value and the actual value, and the actuator is operated based on the control instruction value. By driving, in a system control device that performs feedback control, the control instruction value, a limiter processing unit that applies a limiter set in consideration of the characteristics of the control target, based on the deviation between the target value and the actual value. And a compensating means for obtaining a compensation term for compensating the transient operation of the control instruction value and adding the compensation term to the control instruction value .

As described in the above item (1), if the control instruction value is limited, the followability during transition may be deteriorated. Therefore, in the present invention, based on the deviation between the target value (for example, the target pulley position or the target primary rotation speed) and the actual value (for example, the actual pulley position or the actual primary rotation speed), the transient in the control instruction value (for example, the target primary hydraulic pressure) The compensating term for compensating for the specific operation is obtained, and the actuator is driven based on the value obtained by adding the compensating term to the control instruction value .

As a result, when feedback control is performed, the transient operation can be sufficiently performed without impairing the function of the compensation term for compensating the transient operation when setting the control instruction value. As a result, there is an effect that the followability during the transition is improved.

(4) According to the invention of claim 4, the differential compensation term calculation unit obtains a differential value of the deviation between the target value and the actual value, and the compensation value calculated based on the differential value is used as the compensation term. The system control device according to claim 3 is characterized in that.

The present invention exemplifies the invention of claim 3 as shown in, for example, FIG. 2, and here, as a compensation term for compensating for transient operation, a deviation between a target value and an actual value is used. The differential value is obtained, and the compensation value calculated based on this differential value is used. The compensation value based on the differential value is a value for improving the transient response, like the high frequency component passing through the high pass filter.

For example, as shown in FIG. 2, the output of the feedback calculation unit is processed by the limiter processing unit, but the output from the differential compensation term calculation unit is used as it is to drive the actuator without being limited. can do. As a result, the remarkable effect that the followability can be improved while ensuring necessary safety and the like is achieved.

(5) The invention according to claim 5 provides the system control device according to any one of claims 1 to 4, characterized in that the control instruction value is a pressure. The present invention exemplifies the inventions of claims 1 to 4, and here, a pressure (for example, a target primary hydraulic pressure in a continuously variable transmission) can be adopted as the control instruction value.

(6) The invention according to claim 6 is characterized in that an actuator instruction value calculation unit for converting the control instruction value into a control amount of the actuator is provided.
The gist is the system control device described in any one of to 5.

The present invention exemplifies the inventions of claims 1 to 5, and, for example, as shown in FIG. 1 and FIG.
An actuator instruction value calculation unit is provided. Therefore, the actuator instruction value calculation unit can convert the control instruction value (for example, target primary hydraulic pressure) into the control amount (for example, current or voltage) of the actuator, and the actuator can be controlled based on this control amount. it can.

As the actuator, for example, in the case of a continuously variable transmission, a valve (electromagnetic valve) driven by electromagnetic force for controlling the primary hydraulic pressure can be used. (7) The invention according to claim 7 provides the system control device according to claim 6, characterized in that the control amount of the actuator is a current.

The present invention is an exemplification of the invention of claim 6, wherein an electric current can be used as a control amount of an actuator (for example, the valve). (8) The invention according to claim 8 provides the system control device according to any one of claims 1 to 7, characterized in that the controlled object is a belt type continuously variable transmission.

The present invention exemplifies the inventions of claims 1 to 7, wherein a belt type continuously variable transmission can be adopted as the controlled object. This belt type continuously variable transmission (C
VT) is, for example, a belt type continuously variable transmission in which the gear ratio is controlled by adjusting the holding position of the drive pulley with respect to the belt and the holding position of the driven pulley with respect to the belt.

(9) A ninth aspect of the present invention provides the system control apparatus according to any one of the first to eighth aspects, wherein the feedback control is sliding mode control. The present invention exemplifies the inventions of claims 1 to 8, and here, sliding mode control can be adopted as the feedback control.

The sliding control will be described in detail later, but the state of the controlled object is expressed in a certain phase space, and the system transient state desired by the designer is represented by a function s that represents the state point of the system. The state of the system is controlled so as to be constrained to the switching plane by setting it on the switching plane, and the state is asymptotically converged to the origin of the phase space along the switching plane. This is a method of controlling the controlled object while satisfying the condition.

The function of realizing the above-described system control device configuration in a computer system is, for example,
It can be provided as a program activated on the computer system side. In the case of such a program, for example, a floppy disk, a magneto-optical disk, a CD-RO
It can be used by storing it in a machine-readable recording medium such as a hard disk or a hard disk, loading it into a computer system and starting it as necessary. Besides this, R
The program may be stored as a machine-readable recording medium such as an OM or a backup RAM, and the ROM or the backup RAM may be incorporated into a computer system for use.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the invention to which the system controller of the present invention is applied will be described with reference to the drawings. [First Embodiment] In a first embodiment of the present invention, in a system controller for performing a sliding mode control on a continuously variable transmission, a high-pass filter, a low-pass filter, and a limiter processing unit are provided in order to improve control followability. It is characterized by combining and.

A) FIG. 3 is a block diagram showing a schematic configuration of the continuously variable transmission 2, the control device 4, and the peripheral devices of the first embodiment to which the above-described invention is applied. These belt type continuously variable transmission (hereinafter simply referred to as CVT) 2 and control device 4 are
It is configured as a continuously variable transmission 2 and a control device 4 of an automobile.

The continuously variable transmission 2 includes a drive side primary pulley 10 (corresponding to a drive pulley) including a movable conical disc 6 and a fixed conical disc 8, a movable conical disc 12 and a fixed conical disc 14.
A secondary pulley 16 on the driven side (corresponding to a driven pulley) and a primary pulley cylinder 1 on the driving side.
8, a secondary pulley cylinder 20 on the driven side, a metal belt 22 spanned between the primary pulley 10 and the secondary pulley 16, an oil pump 24 driven by an engine E as an internal combustion engine, a primary hydraulic control actuator 26, A secondary hydraulic control actuator 28 and a starting device 30 such as a torque converter that adjusts the transmission of torque from the engine E are provided.

The control device 4 includes a control unit 32 including an electronic control circuit, a primary rotation sensor 34 for detecting the rotation speed of the primary pulley 10, a secondary rotation sensor 36 for detecting the rotation speed of the secondary pulley 16,
A throttle opening sensor 38 for detecting the throttle opening for adjusting the intake air amount to the engine E, and the engine E
The engine rotation sensor 40 for detecting the rotation speed of the engine is provided.

The control unit 32 is configured as a microcomputer centered on a CPU, and uses the detection data of the primary rotation sensor 34, the secondary rotation sensor 36, the throttle opening sensor 38, and the engine rotation sensor 40 as state detection means. A target gear ratio is set based on the target gear ratio, and the primary hydraulic control actuator 26 is adjusted to achieve this target gear ratio, and the hydraulic pressure generated by the oil pump 24 and supplied to the primary pulley cylinder 18 is controlled. Further, the control unit 32 adjusts the secondary hydraulic pressure control actuator 28 so that the metal belt 22 does not slip, and controls the hydraulic pressure generated by the oil pump 24 and supplied to the secondary pulley cylinder 20.

Here, detailed control executed by the control unit 32 will be described with reference to the control block diagrams of FIGS. 4 and 5. FIG. 4 is a control block diagram on the secondary pulley 16 side, in which the secondary hydraulic control actuator 28 of the secondary pulley cylinder 20 is adjusted to prevent the metal belt 22 from slipping with respect to the secondary pulley 16 so that the movable conical disc is moved. The control processing for sufficiently generating the clamping force between the fixed cone 12 and the fixed conical disc 14 is shown.
Of these, the input torque estimation unit 42 and the target secondary hydraulic pressure calculation unit 44 are realized as programs executed by the CPU of the control unit 32. The secondary hydraulic pressure controller 46 is a drive circuit provided in the control unit 32 for driving the secondary hydraulic pressure control actuator 28.

When the control is started, the input torque estimating unit 4
2 is the engine speed NE and the throttle opening θ and the input torque shown in FIG. 6 based on the throttle opening θ detected by the throttle opening sensor 38 and the engine speed NE detected by the engine rotation sensor 40. The input torque Tin is estimated from the map showing the relationship with Tin.
The input torque Tin is a torque generated in the engine E and input from the engine E to the continuously variable transmission 2 via the starting device 30.

Next, the target secondary hydraulic pressure calculation unit 44
Input torque Tin obtained by the input torque estimation unit 42
And a target gear ratio TRt obtained by a target gear ratio setting unit 48, which will be described later, based on the target secondary oil pressure PSt.
Is calculated. The target secondary hydraulic pressure PSt is a hydraulic pressure at which torque can be transmitted without slippage of the metal belt 22 with respect to the secondary pulley 16, and 3 shown in FIG.
Obtained from the dimensional map.

The target secondary hydraulic pressure P thus obtained
The secondary hydraulic pressure controller 46 drives and controls the secondary hydraulic pressure control actuator 28 based on the signal of St, and the secondary hydraulic pressure PS that does not cause belt slip is realized. FIG. 5 is a control block diagram on the side of the primary pulley 10, in which the primary hydraulic control actuator 26 of the drive side primary pulley cylinder 18 is adjusted so that the primary pulley 10 and the secondary pulley 16 are connected to each other with a metal. The gear shifting performed via the belt 22
The control processing which makes target gear ratio TRt is shown.

Among these, the target gear ratio setting unit 48 and the gear ratio-
Pulley position conversion unit 50, primary hydraulic feedforward term calculation unit 52, sliding mode control unit 54,
An actual gear ratio detector 58, a gear ratio / pulley position converter 60,
The high-pass filter 62, the low-pass filter 64, and the limiter processing unit 66 are realized as a program executed by the CPU of the control unit 32. The primary hydraulic controller 56 is a drive circuit provided in the control unit 32 for driving the primary hydraulic control actuator 26.

The high-pass filter 62 and the low-pass filter 64 may have a hardware configuration instead of a so-called digital filter. When the control is started,
The target gear ratio setting unit 48 includes a throttle opening degree θ detected by the throttle opening degree sensor 38, a secondary rotation speed NS detected by the secondary rotation sensor 36, and the like.
Based on the states of the continuously variable transmission 2 and the engine E that drives the continuously variable transmission 2 obtained from various sensors, the target gear ratio TRt is obtained from a predetermined map.

Next, based on the target gear ratio TRt, the target secondary oil pressure PSt, and the input torque Tin, the primary oil pressure feedforward term calculation unit 52.
Calculates the target primary hydraulic feedforward term P1. In this calculation, first, the target secondary hydraulic pressure PS
Based on t, the maximum torque Tmax that can be transmitted without slippage of the metal belt 22 on the secondary pulley 16 is calculated from the table showing the relationship between the secondary hydraulic pressure PS and the input torque Tin that is measured in advance as shown in FIG. Desired. Next, the torque ratio Tin / Tmax is calculated from the ratio between the input torque Tin and the maximum torque Tmax.

Next, based on this torque ratio Tin / Tmax, based on the primary hydraulic pressure feedforward term calculation map shown in FIG. 9, the hydraulic ratio (PP: primary hydraulic pressure / PS: secondary hydraulic pressure) from the line of the corresponding gear ratio TR. Is calculated, the product of this hydraulic pressure ratio and the target secondary hydraulic pressure PSt is calculated, and the value is taken as the primary hydraulic pressure feedforward term P1.

Specifically, for example, the torque ratio Tin / Tm
When ax = 0.25 and target gear ratio TRt = 2.0, as shown in FIG. 9, the hydraulic pressure ratio (PP / PS) =
0.41 is obtained, and the primary hydraulic feedforward term P1 is obtained when P1 = 0.41 · PSt. In addition,
FIG. 9 is an example, and the map varies depending on the type of the continuously variable transmission 2.

On the other hand, the target gear ratio TRt obtained by the target gear ratio setting unit 48 is converted by the gear ratio / pulley position conversion unit 50 into the target pulley position xt, that is, the target position xt of the movable conical disc 6 of the primary pulley 10. It Next, the actual gear ratio detection unit 58 calculates the actual gear ratio TRr from the ratio of the primary rotation speed NP and the secondary rotation speed NS obtained from the detection of the primary rotation sensor 34 and the secondary rotation sensor 36 of the continuously variable transmission 2. Then, the gear ratio / pulley position conversion unit 60 determines the actual gear ratio TRr as the actual pulley position xr,
That is, it is converted into the actual position xr of the movable conical disc 6 of the primary pulley 10.

The deviation err between the target pulley position xt from the gear ratio / pulley position conversion unit 50 and the actual pulley position xr from the gear ratio / pulley position conversion unit 60 is calculated by the following equation [1], and The deviation err is input to the sliding mode control unit 54. err = xr−xt ... [1] In the sliding mode control unit 54, this deviation err
Based on the above, the primary hydraulic pressure feedback term P2 by the sliding mode control is calculated and output.

Next, the sliding mode control calculation executed by the sliding mode control unit 54 based on the deviation err will be described. Here, first, it is considered that the primary hydraulic feedforward term P1 and the pulley position xt correspond to each other, and from the experimental data for the configuration of FIG. 3, the following approximation is made between the primary hydraulic feedback term P2 and err. It can be considered that the formula [2] holds.

D (err) /dt=A.err+B.P2 ... [2] Here, the values of A and B depend on the secondary hydraulic pressure PS, the input torque Ti, and the gear ratio TR. In order to eliminate the steady deviation, the variable ie defined by the deviation integral calculation of the following equation [3]
Introduce rr.

Ierr = ∫err · dt ... [3] The state point s (the switching surface corresponds to s = 0) in the sliding mode control is defined by the following expression [4]. s = s1.ierr + err ... [4] Based on the above-mentioned formula [4], the primary hydraulic pressure feedback term P2 is calculated as in the following formula [5].

P2 = (− 1 / B0) · ((s1 + A0) · err + k · sat (s)) [5] Note that A0 and B0 are numbers that fluctuate, A and B, respectively.
Is the nominal value of. Further, the saturation function sat () is the function shown in FIG. 10, and d in FIG. 10 is the width of the boundary layer existing on both sides of the switching surface (s = 0) in the phase space shown in FIG. k is a nonlinear feedback term gain (also called a robustness parameter).

In order that the actual pulley position xr follows the target pulley position xt when A and B change and take different values from A0 and B0 respectively, the value of k is expressed by the following inequality [6]. Need to be satisfied. k> max (| dA · err |) + max (| dB · P2 |) ... [6] where dA = | A−A0 |, dB = | B−B0 |
Is. max () indicates to take the maximum value.

The above equation [6] is derived as follows. In the above formula [2], A = A0 + dA, B = B0
If it is + dB, the expression [2] becomes as the following expression [7]. d (err) / dt = (A0 + dA) * err + (B0 + dB) * P2 = A0 * err + B0 * P2 + dA * err + dB * P2 ... [7] At this time, when the expression [4] representing the switching surface is differentiated, the following expression [8] ] It becomes like.

S ′ = s1 · d (ierr) / dt + d (err) / dt = s1 · err + A0 · err + B0 · P2 + dA · err + dB · P2 [8] Substituting the expression [5] into the expression [8]. Then, s'is given by the following equation [9].

S '= s1 * err + A0 * err- (s1 + A0) * err-k * sat (s) + dA * err + dB * P2 = -k * sat (s) + dA * err + dB * P2 ... [9] Here, sliding In order for the mode to exist,
Since it is necessary to satisfy s ′ · s <0, the formula [9]
It is understood that the above equation [6] is sufficient for all of dA and dB to have a different sign from s.

As described above, the primary hydraulic pressure feedback term P2 is determined and added to the primary hydraulic pressure feedforward term P1 determined by the primary hydraulic pressure feedforward term calculation unit 52 to obtain the target primary hydraulic pressure PPt. And this target primary hydraulic pressure PP
Based on the signal of t, the control amount (current value) is calculated by the primary hydraulic pressure controller 56 as described in detail below, and the primary hydraulic pressure control actuator 26 is drive-controlled based on the calculated control amount, and the belt The primary hydraulic pressure PP that does not slip is realized, and the actual gear ratio TRr of the continuously variable transmission 2 is adjusted toward the target gear ratio TRt.

That is, first, the target primary hydraulic pressure PPt
Signal is input to the low-pass filter 64. As is well known, the low-pass filter 62 is a filter that passes only low-frequency components, and therefore the limiter processing unit 66.
Only the low-frequency component of the target primary hydraulic pressure PPt is input to.

The limiter processing section 66 is used when the target primary oil pressure PPt is out of a predetermined range (for example, when it is lower than the lower limit value).
This is a means for performing a process of applying a so-called limiter by cutting t, and setting it within a predetermined range (for example, a lower limit value). Therefore, when the low frequency component of the target primary hydraulic pressure PPt deviates from the predetermined range, , The deviated low frequency component is cut. In particular, here, a case where all low frequency components are cut will be described.

The predetermined range is an allowable range of the target primary hydraulic pressure PPt set from the viewpoint of the structure and safety of the continuously variable transmission 2. Therefore, the low frequency component of the target primary oil pressure PPt is not input to the primary oil pressure controller 56.

On the other hand, the signal of the target primary oil pressure PPt is inputted not only to the low pass filter 62 but also to the high pass filter 62. As is well known, the high-pass filter 62 is a filter that allows only a high-frequency component to pass, that is, a filter that allows a component for compensating the operation of the primary hydraulic control actuator 26 during a transition, and therefore the primary hydraulic controller 56. A high-frequency component of the target primary hydraulic pressure PPt is input to.

That is, unlike the low frequency component, this high frequency component is not limited by the limiter processing unit 66, and therefore is input to the primary hydraulic pressure controller 56 as it is. Therefore, the primary hydraulic controller 56
Then, the target primary oil pressure P corresponding to this high frequency component
Only Pt is converted into a current value which is a control amount, and the current having the current value is output to the primary hydraulic control actuator 26.

When there is a low frequency component within the allowable range, the target primary hydraulic pressure PPt obtained by adding the low frequency component to the high frequency component is converted into a current value. The primary hydraulic pressure control actuator 26 is a valve (electromagnetic valve) whose opening / closing operation is controlled by an electromagnetic force, and the opening / closing of this valve adjusts the primary hydraulic pressure. That is, the current corresponding to the high-frequency component of the target primary oil pressure PPt is applied to the solenoid valve to control the opening / closing of the valve and adjust the primary oil pressure.

B) Next, the function and effect of the first embodiment having the above-mentioned structure will be described. The first embodiment includes a high pass filter 62, a low pass filter 64, and a limiter processing unit 66.

Then, the low-pass filter 64 extracts only the low-frequency component from the components of the target primary hydraulic pressure PPt. This low frequency component, that is, the component corresponding to the offset in the steady state is input to the limiter processing unit 66,
It is cut by applying a so-called limiter. This ensures the safety of control and the like.

On the other hand, the high pass filter 62 extracts only the high frequency component from the components of the target primary oil pressure PPt. This high frequency component, that is, the component for improving (compensating) the transient response, is directly input to the primary hydraulic pressure controller 56, converted into a current, and used for driving the primary hydraulic pressure control actuator 26. This allows
Since the transient response of the primary hydraulic control actuator 26 is improved, the actual value (actual position xr, and therefore the actual gear ratio TR
t) is a target value (target position xt, and therefore target gear ratio TR
It is possible to quickly follow r).

That is, the safety is ensured by providing the high-pass filter 62 and the low-pass filter 64, cutting only the low-frequency component from the low-pass filter 64 by the limiter processing section 66, and using the high-frequency component for the valve control. In addition to the above, a remarkable effect that control followability can also be realized is achieved.

Therefore, here, the high-pass filter 62 is used.
However, it will function as a limiter restriction unit that prohibits applying a limiter. The control state in the first embodiment is shown in FIG. As is apparent from FIG. 12, the target primary hydraulic pressure PP of the line a is
Since it can be set smaller than the limiter on the line b, the actual primary hydraulic pressure on the line c can be brought close to the desired primary hydraulic pressure.

As a result, as shown in FIG. 13, the actual value (actual position xr, therefore the actual gear ratio TRt) can be made to quickly follow the target value (target position xt, therefore the target gear ratio TRr). [Second Embodiment] Next, a second embodiment will be described.

In the second embodiment, in a system controller for performing a sliding mode control on a continuously variable transmission, a differential compensation term calculation unit and a limiter processing unit are combined in order to improve control followability. There is a feature in the point. In addition, the same description as in the first embodiment will be given below.
Omit or simplify.

A) First, the control configuration on the primary pulley side will be described with reference to FIG. FIG. 14 is a control block diagram on the primary pulley side. The control configuration on the continuously variable transmission side and the secondary pulley side is the same as that of the first embodiment, and the same symbols are used for the same configurations.

FIG. 14 shows that the primary hydraulic pressure control actuator 26 of the drive-side primary pulley cylinder 18 is adjusted to shift gears between the primary pulley 10 and the secondary pulley 16 via the metal belt 22. Shows a control process for setting the target gear ratio TRt.

Among these, target gear ratio setting unit 148, gear ratio-pulley position conversion unit 150, primary hydraulic feedforward term calculation unit 152, sliding mode control unit 154, actual gear ratio detection unit 158, gear ratio-pulley position conversion. The section 160, the differential compensation term calculation section 162, and the limiter processing section 166 are the CPU of the control unit 32.
Is implemented as a program to be executed by. Further, the primary hydraulic pressure controller 56 is provided in the control unit 32, and the primary hydraulic pressure control actuator 26 is provided.
Is a drive circuit for driving.

When the control is started, the target gear ratio setting unit 1
Reference numeral 48 denotes the continuously variable transmission 2 and the continuously variable transmission 2 obtained from various sensors such as the throttle opening θ detected by the throttle opening sensor 38 and the secondary rotation speed NS detected by the secondary rotation sensor 36. The target gear ratio TRt is obtained from a predetermined map based on the state of the engine E to be driven.

Next, based on the target gear ratio TRt, the target secondary hydraulic pressure PSt, and the input torque Tin, the primary hydraulic pressure feedforward term calculation unit 152.
Calculates the target primary hydraulic feedforward term P1 in the same manner as in the first embodiment.

On the other hand, the target gear ratio TRt obtained by the target gear ratio setting unit 148 is calculated by the gear ratio / pulley position conversion unit 150 as the target pulley position xt, that is, the primary pulley 1
The target position xt of the movable conical disc 6 is converted to 0. next,
The actual gear ratio detection unit 158 obtains the actual gear ratio TRr from the ratio of the primary rotation speed NP and the secondary rotation speed NS actually obtained from the detection of the primary rotation sensor 34 and the secondary rotation sensor 36 of the continuously variable transmission 2, The gear ratio / pulley position conversion unit 160 converts the actual gear ratio TRr into the actual pulley position xr, that is, the actual position xr of the movable conical disc 6 of the primary pulley 10.

The deviation err between the target pulley position xt from the gear ratio / pulley position conversion unit 150 and the actual pulley position xr from the gear ratio / pulley position conversion unit 160 is the above equation [1].
And the deviation err is input to the sliding mode control unit 154.

In the sliding mode controller 154,
Based on this deviation err, the primary hydraulic pressure feedback term P2 by sliding mode control is calculated and output as in the first embodiment. Next, this primary hydraulic pressure feedback term P2 is added to the primary hydraulic pressure feedforward term P1 calculated by the primary hydraulic pressure feedforward term calculation unit 152 to obtain the target primary hydraulic pressure PPt.

This target primary hydraulic pressure PPt is input to the limiter processing unit 166. Limiter processing unit 166
When the target primary hydraulic pressure PPt is out of the predetermined range, the target primary hydraulic pressure PPt is cut,
The target primary hydraulic pressure PPt is a means for performing processing for applying a so-called limiter and setting it within a predetermined range.
Is deviated from the predetermined range, the deviated portion is cut.

Therefore, the primary hydraulic controller 56 has
Only the target primary hydraulic pressure PPt within the allowable range is input. On the other hand, the above-mentioned deviation err is calculated by the differential compensation term calculation unit 1
It is also input to 62. In the differential compensation term calculation unit, the deviation er
r is differentiated, the differential value err 'is calculated, and the differential value err' is multiplied by a predetermined coefficient to calculate a compensation value. The differential value err 'is a difference err, that is, a difference between the actual value (actual position xr, therefore the actual gear ratio TRt) and the target value (target position xt, therefore the target gear ratio TRr), The compensation value calculated based on the differential value err 'is a compensation term for improving the transient response, like the high frequency component described above.

Therefore, the primary hydraulic controller 56 is
In addition to the target primary hydraulic pressure PPt within the allowable range, the compensation value obtained from this differential value err 'is input. The primary hydraulic pressure controller 156 calculates a control amount (current value) based on the target primary hydraulic pressure PPt within the allowable range and the compensation value obtained from the differential value err ', and the current of the current value is used as the primary hydraulic pressure. Output to the control actuator 26.

Primary hydraulic control actuator 26
Is controlled by the current to realize the primary hydraulic pressure PP that does not cause belt slip, and the actual speed ratio TRr of the continuously variable transmission 2 is adjusted toward the target speed ratio TRt. b) Next, the function and effect of the second embodiment having the above-described configuration will be described.

In the second embodiment, the differential compensation term calculation unit 1
62 and a limiter processing unit 166. Then, the limiter calculation unit 166 cuts the target primary hydraulic pressure PPt by applying a limiter. This ensures the safety of control and the like.

On the other hand, the differential compensation term calculator 162 calculates the differential value err 'of the deviation err, and this differential value er
A value obtained by multiplying r ′ by a predetermined coefficient is calculated as a compensation value. Since the transient response of the primary hydraulic control actuator 26 is improved by using the compensation value for driving the primary hydraulic control actuator 26, the actual value (actual position xr, and thus the actual gear ratio TRt) is set to the target value ( It is possible to quickly follow the target position xt, and thus the target gear ratio TRr).

In other words, the configuration of the differential compensation term calculation unit 162 and the limiter processing unit 166 has the remarkable effect that the safety can be secured and the control followability can be realized. Therefore, here, the differential compensation term calculation unit 162 functions as a compensation unit for adding the compensation term.

FIG. 1 shows the control state in the second embodiment.
5 shows. As is apparent from FIG. 15, when the limiter is applied, the current value and the target primary hydraulic pressure are as shown by lines a and b, respectively, and the actual primary hydraulic pressure of line c is the line d.
It deviates from the desired primary hydraulic pressure. as a result,
The actual value (actual position xr, that is, the actual gear ratio TRt) is the target value (target position xt, that is, the target gear ratio T of the line f as shown by the line e
It deviates greatly from Rr).

On the other hand, when the compensation value based on the differential value err 'is used, the current value once becomes a very large value at the start of the transient state as shown by the line g. The hydraulic pressure becomes a value close to the desired primary hydraulic pressure on the line d. As a result, the actual value (actual position xr, and hence the actual gear ratio T
Rt) quickly approaches the target value (target position xt, and thus target gear ratio TRr) of line f, as shown by line i, and has excellent followability.

Needless to say, the present invention is not limited to the examples of the above-described embodiment, and can be carried out in various modes without departing from the scope of the present invention.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating the invention of claim 2;

FIG. 2 is a block diagram illustrating the invention of claim 4;

FIG. 3 is a block diagram showing a schematic configuration of a continuously variable transmission, a control device, and peripheral devices according to the first embodiment.

FIG. 4 is a control block diagram of a secondary pulley according to the first embodiment.

FIG. 5 is a control block diagram of the primary pulley according to the first embodiment.

FIG. 6 is a map showing a relationship between an engine speed NE, a throttle opening θ and an input torque Tin in the first embodiment.

FIG. 7 is a diagram showing a target secondary hydraulic pressure PS based on an input torque Tin and a target gear ratio TRt in the first embodiment.
It is a three-dimensional map for obtaining t.

FIG. 8 is a graph showing the relationship between the secondary hydraulic pressure PS and the input torque Tin in the first embodiment.

FIG. 9 is a map showing a relationship between a torque ratio Tin / Tmax according to a gear ratio TR and a hydraulic pressure ratio PP / PS in the first embodiment.

FIG. 10 is a saturation function sat according to the first embodiment.
It is a graph which shows (s).

FIG. 11 is a graph showing boundary layers existing on both sides of a switching surface (s = 0) in the phase space of the control system in the first embodiment. It is

FIG. 12 is a timing chart showing a control state in the first embodiment.

FIG. 13 is a timing chart showing the relationship between the actual value and the target value in the first embodiment.

FIG. 14 is a control block diagram of a primary pulley in the first embodiment.

FIG. 15 is a timing chart showing a control state in the first embodiment.

FIG. 16 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

E ... Engine 2 ... Continuously Variable Transmission 4 ... Control Device 6 ... Movable Cone 8 ... Fixed Cone 10 ... Primary Pulley 12 ... Movable Cone 14 ... Fixed Cone 16 ... Secondary Pulley 18 ... Primary Pulley Cylinder 20 ... Secondary Pulley Cylinder 22 ... Metal belt 24 ... Oil pump 26 ... Primary hydraulic control actuator 28 ... Secondary hydraulic control actuator 30 ... Start device 32 ... Control unit 34 ... Primary rotation sensor 36 ... Secondary rotation sensor 38 ... Throttle opening sensor 40 ... Engine rotation sensor 42 ... Input torque estimation unit 44 ... Target secondary hydraulic pressure calculation unit 46 ... Secondary hydraulic pressure controller 48, 148 ... Target gear ratio setting unit 50, 150 ... Gear ratio-pulley position conversion unit 52, 152 ... Primary hydraulic feedforward term calculation unit 54, 154 ... Sliding mode controller 56, 156 ... Primary hydraulic pressure controller 58, 158 ... Actual gear ratio detector 60, 160 ... Gear ratio-pulley position converter 62 ... High pass filter 64 ... Low pass filter 66, 166 ... Limiter processing Unit 162 ... Differential compensation term calculation unit

Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) F16H 59/00-61/12 F16H 61/16-61/24 F16H 63/40-63/48

Claims (9)

(57) [Claims] 1. Feedback control is performed by calculating a control instruction value that brings an actual value of a controlled object closer to a target value from a deviation between the target value and the actual value, and driving an actuator based on the control instruction value. In the system control device to be performed, the control instruction value, a limiter processing unit for applying a limiter set in consideration of the characteristics of the control target, and a compensation term for compensating for a transient operation in the control instruction value, A system control device comprising: a limiter limiting unit that limits processing for applying a limiter. 2. An output from the static component filter, comprising: a dynamic component filter that passes only a signal that indicates a transient operation; and a static component filter that passes only a signal that indicates a steady operation. The system control device according to claim 1, further comprising: a process of applying the limiter. 3. A feedback control is performed by calculating a control instruction value that brings an actual value of a controlled object close to a target value from a deviation between the target value and the actual value, and driving an actuator based on the control instruction value. In the system control device to perform, the control instruction value, a limiter processing unit for applying a limiter set in consideration of the characteristics of the control target, based on the deviation between the target value and the actual value, the transition of the control instruction value And a compensating means for adding the compensation term to the control instruction value to obtain a compensation term for compensating the dynamic operation. 4. The differential compensation term calculation unit obtains a differential value of the deviation between the target value and the actual value, and the compensation value calculated based on the differential value is used as the compensation term. 3. The system control device according to item 3. 5. The system control device according to claim 1, wherein the control instruction value is pressure. 6. The system control device according to claim 1, further comprising an actuator instruction value calculation unit that converts the control instruction value into a control amount of the actuator. 7. The system controller according to claim 6, wherein the control amount of the actuator is a current. 8. The system control device according to claim 1, wherein the control target is a belt type continuously variable transmission. 9. The method according to claim 1, wherein the feedback control is sliding mode control.
8. The system control device according to any one of 8.