JP5724318B2 - Feedback control device - Google Patents

Description

  The present invention includes a detector that detects an actual control amount, a controller that operates an operation amount of a control target to control the actual control amount detected by the detector to a target control amount, and the target control amount The present invention relates to a feedback control device including an integrator that operates the operation amount in accordance with a cumulative value of deviation from the actual control amount.

  Generally, in manual transmission vehicles, gear shifting is performed by the driver depressing the clutch pedal to release the clutch, operating the shift lever to switch the transmission gear, and then depressing the clutch pedal to re-engage the clutch. Is done. However, in order to perform a smooth gear shift, a delicate operation of the clutch pedal is required, which is not easy for beginners of driving. Therefore, an automatic clutch that automatically performs clutch operation during gear shifting has been proposed and put into practical use.

  Such an automatic clutch includes a concentric slave cylinder (CSC) that operates based on clutch operating hydraulic pressure generated by a master cylinder. Conventionally, as such a CSC, one having a two-divided piston as shown in Patent Document 1 is known.

  As shown in FIG. 4, a substantially circular tube-shaped outer housing 52 is disposed on the outer periphery of a substantially circular tube-shaped inner housing 51. Between the inner housing 51 and the outer housing 52, a first piston 53 and a second piston 54, both of which are formed in an annular shape, are disposed so as to be reciprocally slidable in the axial direction of the CSC. A pressure chamber 55 to which the clutch operating hydraulic pressure generated by the master cylinder is supplied is defined on the right side of the first piston 53 in the drawing.

  The second piston 54 is connected to a friction clutch (both not shown) via a diaphragm spring, and is biased rightward in the drawing by the diaphragm spring. The second piston 54 is urged to the left in the drawing by a spring 56. The second piston 54 when the clutch operating hydraulic pressure in the pressure chamber 55 is unloaded is positioned at a position where the spring force of the diaphragm spring and the spring 56 is balanced.

  In the CSC configured as described above, when the clutch operating oil pressure is introduced into the pressure chamber 55, the first piston 53 is displaced to the left in the drawing. Then, the second piston 54 is pushed to the left in the figure by being pushed by the first piston 53, thereby releasing the friction clutch.

  On the other hand, as an automatic clutch feedback control device, a device described in Patent Document 2 is known. The feedback control device described in the document includes an integrator that performs feedback control in accordance with a cumulative value of deviation between a target value of CSC piston displacement and an actual value. Patent Document 3 discloses a feedback control device for an automatic clutch that performs proportional integral control of piston displacement and stops control when the feedback integral value exceeds a specified value, thereby preventing excessive hydraulic pressure from acting. It is disclosed.

JP 2010-164110 A JP 11-193832 A JP-A-01-269729

  By the way, in the automatic clutch provided with the above-described two-divided piston, the first piston 53 is pushed by the clutch operating hydraulic pressure in the pressure chamber 55 and the state in contact with the second piston 54 is maintained. . Here, as shown in FIG. 5A, when the clutch operating hydraulic pressure in the pressure chamber 55 is unloaded, if the external force F is applied from the friction clutch side serving as the cylinder load of the CSC, the second piston 54 is actuated. Is pushed to the right in the drawing, and accordingly, the first piston 53 is also displaced to the right in the drawing. Thereafter, when the external force no longer acts, the second piston 54 moves back to the original position by the spring force of the spring 56, but the first piston 53 to which such a spring force does not act remains in the displaced position. As a result, a gap C is generated between the first piston 53 and the second piston 54 as shown in FIG.

  FIG. 6 shows the transition of the actual displacement of the second piston 54 when the target trajectory of the displacement of the second piston 54 is set as indicated by the dotted line in the same figure and no gap C is generated between the pistons. It is shown with a solid line. Further, in the figure, the transition of the actual displacement of the second piston 54 when the gap C is generated between the pistons is indicated by a one-dot chain line.

  When the supply of the clutch operating hydraulic pressure to the pressure chamber 55 is started, the first piston 53 starts to be displaced to the cylinder load side. Here, if the gap C is not generated between the pistons, the second piston 54 is displaced simultaneously with the displacement of the first piston 53. However, if the gap C is generated between the pistons, even if the first piston 53 starts moving, the second piston 54 is not displaced until the gap C is closed. Therefore, the response delay of the actual displacement of the second piston 54 at this time increases more than when the gap C is not generated between the pistons. If the response delay increases, the absolute value of the feedback integral value increases during that time, so that the actual displacement easily exceeds the target displacement and overshoots easily.

  Even in a CSC in which the piston is not divided, if the piston displacement stagnates at the control start point due to temporary sticking or the like and the response delay increases, the absolute value of the feedback integral value also increases, and the overshoot also occurs. It becomes easy to do. Also, in the feedback control system other than the CSC of the automatic clutch, if the actual control amount stagnates near the value at the start of control, the same problem may occur due to an increase in the feedback integral term.

  The present invention has been made in view of such circumstances, and the problem to be solved is that the actual control amount when the response delay increases due to the stagnation of the actual control amount in the vicinity of the value at the start of control. An object of the present invention is to provide a feedback control device capable of suitably suppressing overshoot.

The invention according to claim 1 is directed to a system comprising a first moving body that is displaced by an actuator and a second moving body that is displaced by receiving a pressure from the first moving body, A detector for detecting the displacement of the second moving body as an actual control amount; a controller for operating an operation amount for operating the actuator to control the actual control amount to a target control amount; a target control amount and an actual control amount; The premise is a feedback control device that includes an integrator that operates an operation amount in accordance with a cumulative value of deviation from the control amount. In order to solve the above problem, the invention according to claim 1 determines whether or not the actual control amount is stagnating near the value at the start of control, and the determination unit determines whether the actual control amount is stagnant. And an initialization unit for instructing re-execution of control of the actual control amount to the target control amount after initializing control when it is determined that the An observer for detecting and estimating a state quantity of the control target including a control quantity, further comprising a target trajectory setting unit for setting a target trajectory of the actual control quantity from a control start point to a control completion point, and the initialization parts, upon initialization of the control, instructs the initialization of the state quantity to the observer instructs the initialization of the target trajectory to the target trajectory setting unit, the actual control amount to the target control amount As the control of So that the target track is re-set by target trajectory setting unit.

  In the above configuration, when the stagnation of the actual control amount near the value at the start of control occurs and the response delay increases, the control is initialized and the feedback control is started again from the beginning. Therefore, an increase in the absolute value of the accumulated value (feedback integral value) of the deviation in the response delay period due to the stagnation of the actual control amount is suppressed. Therefore, according to the above configuration, it is possible to suitably suppress the overshoot of the actual control amount when an increase in response delay due to the stagnation of the control amount near the value at the start of control occurs. Here, the initialization of the control means returning the target control amount, the operation amount of the control target, and the state amount to the values at the start of the control.

In addition , in the configuration including an observer that detects and estimates the state quantity of the control target including the actual control quantity as a detector, the initialization unit is configured to initialize the state quantity estimated by the observer, thereby controlling the state quantity. Can be initialized.

Also, in the configuration including the target trajectory setting unit for setting a target trajectory of the actual control quantity of the control start point to the control completion point, by configuring an initialization unit to initialize the target trajectory, the control Initialization can be performed.

Such feedback control system of the present invention, first be displaced by a first moving body which is displaced by an actuator that operates in response to the operation amount operated by the controllers, the pressure from the first moving body that The present invention is particularly suitable for application to a control system in which a system comprising two moving bodies is a control target and a detector is configured to detect the displacement of the second moving body as an actual control amount. ing.

Further, the feedback control device of the present invention can be applied to a control system in which the piston displacement of the concentric slave cylinder of the automatic clutch that connects and disconnects the torque transmission of the vehicle is an actual control amount, as in claim 2. is there.

The block diagram which shows typically the structure of the feedback control apparatus which concerns on one embodiment of this invention. The time chart which shows transition of the target track | orbit and actual displacement of the 2nd piston in the embodiment. The flowchart of the clutch servo control routine employ | adopted as the same embodiment. Sectional drawing which shows the side part cross-section of CSC of an automatic transmission. (A), (b) Sectional drawing which each shows the state of the 1st and piston before and behind each external force effect | action. The time chart which shows transition of the target trajectory and actual displacement of a 2nd piston in the conventional feedback control apparatus.

(First embodiment)
Hereinafter, an embodiment of a feedback control device according to the present invention will be described in detail with reference to FIGS. In the present embodiment, the feedback control device of the present invention is controlled by the CSC of the automatic clutch provided with the piston of the two-part structure shown in FIG. 4, and the displacement of the second piston 54 of the CSC is actually controlled. It is applied to the control system for quantity.

  First, the configuration of the feedback control apparatus of the present embodiment will be described with reference to FIG. The feedback control device of the present embodiment controls the supply current of the master cylinder 1 to set the actual displacement RY of the second piston 54 (see FIG. 4) of the concentric slave cylinder (CSC) 2 as the target displacement TY. To implement clutch servo control.

  As shown in the figure, a target trajectory setting unit 3 is provided in this feedback control device. The target trajectory setting unit 3 moves the trajectory of the second piston 54 from the control start point that is the displacement of the second piston 54 at the start of the clutch operation to the control end point that is the displacement of the second piston 54 at the completion of the clutch operation. A target trajectory TR) is set. The target trajectory setting unit 3 calculates and outputs a target displacement TY from the target trajectory TR. The target displacement TY indicates the position of the target trajectory TR at that time, and is a function that changes along the target trajectory TR from the control start point to the control completion point as time elapses.

  On the other hand, the actual displacement RY of the second piston 54 is detected by the observer 6 as a detector. The observer 6 inputs an actual displacement RY and a control input U described later, and calculates estimated state quantities X0, X1, X2 and an estimated displacement PY based on them. The estimated state quantities X0, X1, and X2 indicate state quantities that are not actually measured among the state quantities constituting the operation model of the second piston 54. Then, the observer 6 calculates the estimated displacement PY of the second piston 54 based on the estimated state quantities X0, X1, and X2.

  In this feedback control device, a deviation E between the current target displacement TY obtained from the target trajectory TR set by the target trajectory setting unit 3 and the estimated displacement PY calculated by the observer 6 is input to the integrator 5. The integrator 5 integrates the deviation E between the estimated displacement PY and the target displacement TY with time to calculate an error integrated value Z that is a cumulative value of the deviation E, and outputs it to the sliding mode controller 4.

  The sliding mode controller 4 inputs the estimated state quantities X0, X1, and X2 calculated by the observer 6 and the deviation E in addition to the error integrated value Z calculated by the integrator 5. Then, the sliding mode controller 4 calculates the control input U based on the deviation E, the estimated state quantities X0, X1, X2 and the error integral value Z, and after performing a guard process for limiting the input, Output.

  The control input U corresponds to the current supplied to the master cylinder 1 and determines the displacement speed of the first piston 53 (see FIG. 4) of the CSC 2 and consequently the displacement speed of the second piston 54 of the CSC 2. It has become. That is, if the value of the control input U increases, the amount of oil supplied from the master cylinder 1 to the pressure chamber 55 of the CSC 2 increases, and the displacement speed of the first piston 53 and thus the second piston 54 increases. Become. On the other hand, if the value of the control input U decreases, the amount of oil supplied from the master cylinder 1 to the pressure chamber 55 of the CSC 2 decreases, so that the displacement speed of the first piston 53 and consequently the second piston 54 decreases. Become. Incidentally, in the present embodiment, the supply current to the master cylinder 1 as the control input U is a parameter corresponding to the operation amount to be controlled.

  Further, the feedback control apparatus of the present embodiment is provided with a stagnation monitoring unit 7 as a determination unit and an initialization unit. The stagnation monitoring unit 7 inputs the actual displacement RY of the second piston 54 and monitors whether the actual displacement RY is stagnating in the vicinity of the control start point. Then, when the stagnation of the actual displacement RY is confirmed, the stagnation monitoring unit 7 instructs the observer 6 to initialize (reset) the estimated state quantities X0, X1, X2 and the estimated displacement PY. Further, the stagnation monitoring unit 7 at this time instructs the target track setting unit 3 to initialize the target track TR.

  As shown in FIG. 2, also in this embodiment, if the gap between the first piston 53 and the second piston 54 as described above is generated, the response delay of the actual displacement RY after the start of control increases. To come. However, in the present embodiment, even if the response delay increases in this way, if the stagnation near the control start point of the actual displacement RY is confirmed (time T1), the estimated state quantities X0, X1, X2 and the target trajectory TR Is initialized, and control is restarted from the beginning. For this reason, an increase in the error integral value Z, which is a cumulative value of the deviation E between the target displacement TY and the actual displacement RY, can be suppressed according to the increase in response delay, and the occurrence of overshoot can be avoided. .

  FIG. 3 shows a flowchart of a clutch servo control routine employed in this embodiment. This routine is executed by the feedback control device together with the start of the clutch servo control.

  When the clutch servo control is started, first, at step S100, it is determined whether or not the actual displacement RY of the second piston 54 is stagnating in the vicinity of the control start value (control start point). In this determination, all of the following provisional stagnation determination conditions (A) to (C) are satisfied, and further, the stagnation determination condition (D) below is satisfied, so that it is determined that there is a stagnation. It has become.

(A) The supply current of the master cylinder 1 is not in the range of null current ± current threshold value α.
(B) The deviation E between the target displacement TY and the actual displacement RY is greater than or equal to the deviation threshold β.
(C) The elapsed time after the start of control is equal to or greater than the determination value γ.

(2) The state where the change amount of the actual displacement RY within the specified time is not more than the change amount threshold value ε continues for the specified determination time or longer.
The temporary stagnation determination condition (A) is for preventing the supply current to the master cylinder 1 from becoming excessive and for not erroneously determining that there is a stagnation when trying to displace the second piston 54 at a very low speed. Is set. The provisional stagnation determination condition (b) is set in order not to erroneously determine that there is a stagnation when trying to displace the second piston 54 at a very low speed. Further, the provisional stagnation determination condition (c) is set so that the non-response state after the start of control is not erroneously determined as stagnation.

  If it is determined that there is no stagnation (S100: NO), normal processing of clutch servo control is performed in step S103. In this normal process, the supply current to the master cylinder 1 is feedback-adjusted so that the actual displacement RY follows the target displacement TY that moves along a preset target trajectory TR.

  On the other hand, if it is determined that there is a stagnation (S100: YES), the estimated state quantities X0, X1, and X2 are initialized in step S101, and the values of the estimated state quantities X0, X1, and X2 are the initial values. Returned to In the subsequent step S102, the target trajectory TR is initialized, and the target trajectory TR is reset so that the time point is the control start point. In this case, after initializing the control in this way, normal processing of clutch servo control in step S103 is performed.

  When the normal processing of the clutch servo control is performed, in step S104, it is determined whether or not the clutch servo control is completed, that is, whether or not the actual displacement RY of the second piston 54 has reached the control completion point. Is done. Here, if the clutch servo control is completed (S104: YES), the processing of this routine at this time is terminated. If not (S104: NO), the processing is returned to step S100.

  In the present embodiment described above, the master cylinder 1 is used as the actuator that operates according to the operation amount, the first piston 53 is used as the first moving body that is displaced by the actuator, and the second piston is used as the second piston. Reference numerals 54 respectively correspond to the second moving bodies that are displaced by being pressed by the first moving body.

According to the above embodiment, the following effects can be obtained.
(1) In the present embodiment, it is determined whether or not the actual displacement RY of the second piston 54, which is the controlled variable, is stagnating near the value at the start of control, and the actual displacement RY is stagnating. When the determination is made, the target trajectory TR and the estimated state quantities X0, X1, and X2 are initialized. In the present embodiment, when the stagnation of the actual displacement RY near the value at the start of control occurs due to the generation of a gap between the first piston 53 and the second piston 54, the response trajectory TR increases. And the estimated state quantities X0, X1, and X2 are initialized, and the control is restarted from the beginning. Therefore, an increase in the absolute value of the error integrated value Z in the response delay period due to the stagnation of the actual displacement RY is suppressed. Therefore, according to the above configuration, it is possible to suitably suppress overshoot of the actual displacement RY when an increase in response delay occurs due to the stagnation of the actual displacement RY near the value at the start of control.

  (2) Even in a control system in which a gap is generated between the first piston 53 and the second piston 54 and the response delay may increase, it is possible to suitably suppress the occurrence of overshoot due to the increase in the response delay. it can. Therefore, even in such a control system, feedback control can be suitably performed.

(3) Since overshoot does not occur, the same control performance as when the clutch is engaged can be obtained even when a gap between the pistons is generated.
(4) Since overshoot does not occur, it is possible to prevent the actuator (master cylinder 1) from hitting the stopper and protect the actuator.

In addition, the said embodiment can also be changed and implemented as follows.
In the above embodiment, the sliding mode controller 4 is used as a controller. However, the present invention is applicable to a control system that employs a controller other than the sliding mode controller as long as the control system includes an integrator. The present invention can be applied in a manner similar to or equivalent to the above embodiment.

  In the above embodiment, the observer 6 that detects and estimates the state quantity of the CSC2 including the actual displacement RY is provided as a detector, and the estimated state quantities X0, X1, and X2 estimated by the observer 6 are initialized. The control was initialized. The present invention can also be applied to a control system that does not perform estimation of the state quantity of the controlled object by the observer 6 or feedback control using the estimated state quantity. Even in such a case, if the target trajectory TR and the target control amount are initialized, an increase in the absolute value of the error integral value Z due to the stagnation of the actual control amount at the control start point can be suppressed, and overshoot can be suppressed. Become.

  In the above embodiment, the feedback control is performed so that the actual displacement RY changes following the target trajectory TR set by the target trajectory setting unit 3 from the control start point to the control completion point. The present invention can also be applied to a control system that does not set the target trajectory TR. Even in such a case, if the target control amount and the state quantity of the control target are initialized, the increase in the absolute value of the error integral value Z due to the stagnation of the actual control amount at the control start point can be suppressed, and overshoot can be suppressed. It becomes possible.

  In the above embodiment, a CSC having a bipartite structure piston is a control target. However, even in a CSC having a non-partition structure piston, the piston displacement is controlled at the start of control due to temporary fixation of the piston. Response delay may increase due to stagnation in the vicinity of the value. Even in such a case, the absolute value of the error integral value becomes excessive during the response delay, and an overshoot may occur. Even in such a case, if the state quantity and the target trajectory are initialized according to the confirmation of such stagnation, the occurrence of overshoot can be suppressed.

  In the above embodiment, the CSC of the automatic clutch that connects and disconnects the torque transmission of the vehicle is the control target. However, the feedback control device and the feedback control method of the present invention can be similarly applied to other control systems. it can. That is, the present invention includes a detector that detects an actual control amount, a controller that operates an operation amount of a control target to control the actual control amount detected by the detector to a target control amount, and a target control amount. The present invention can be applied to any feedback control device that includes an integrator that manipulates an operation amount in accordance with a cumulative value of deviation between the actual control amount and the actual control amount.

  The present invention includes a first moving body that is displaced by an actuator that operates according to an operation amount operated by a controller, a second moving body that is displaced by receiving a pressure from the first moving body, It is particularly suitable to apply to a control system in which a detector is configured to detect a displacement of the second moving body as a control amount. That is, the present invention detects the displacement of the second moving body that is indirectly displaced by the actuator through the pressing of the first moving body, not the first moving body that is directly displaced by the actuator, and provides feedback. Application to a control system that performs control is more suitable.

DESCRIPTION OF SYMBOLS 1 ... Master cylinder (actuator), 2 ... Concentric slave cylinder (CSC: Control object), 3 ... Target track setting part, 4 ... Sliding mode controller (controller), 5 ... Integrator, 6 ... Observer (detector), 7: Stagnation monitoring unit (determination unit, initialization unit ), 51 ... Inner housing, 52 ... Outer housing, 53 ... First piston (first moving body), 54 ... Second piston (second moving body), 55 ... Pressure chamber, 56 ... Spring.

Claims (2)

A system comprising a first moving body that is displaced by an actuator and a second moving body that is displaced by receiving a pressure from the first moving body is a control target.
A detector for detecting the displacement of the second moving body as an actual control amount; a controller for operating an operation amount for operating the actuator to control the actual control amount to a target control amount; and the target control amount; In a feedback control device comprising: an integrator that operates the operation amount in accordance with a cumulative value of deviation from the actual control amount;
A determination unit for determining whether or not the actual control amount is stagnating near a value at the start of control;
An initialization unit for instructing re-execution of control of the actual control amount to the target control amount after initializing control when it is determined by the determination unit that the stagnation of the actual control amount has occurred And comprising
The detector is an observer that detects and estimates the state quantity of the control target including the actual control quantity,
A target trajectory setting unit for setting a target trajectory of the actual control amount from the control start point to the control completion point;
Wherein the initialization unit, upon initialization of the control, instructs the initialization of the state quantity to the observer instructs the initialization of the target trajectory to the target trajectory setting unit,
The feedback control device according to claim 1, wherein the target trajectory is reset by the target trajectory setting unit in accordance with the control of the actual control amount to the target control amount . The feedback controller, the feedback control apparatus according to claim 1, formed by applying the piston displacement of the concentric slave cylinder of an automatic clutch which a torque transmission of a vehicle control system to the actual control quantity.

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