JP3479211B2 - Solenoid drive - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solenoid drive device, and more particularly to a technique for controlling a drive current of a solenoid used for hydraulic control in a hydraulic automatic transmission for a vehicle, for example.

[0002]

2. Description of the Related Art Conventionally, a current actually flowing in a solenoid is detected, and a feedback control of an energization operation amount (for example, duty) is performed so that the actual current reaches a target value. There is known a solenoid drive device capable of controlling to a target current even if there is a variation in power supply voltage (Japanese Patent Laid-Open No. 3-19935).
No. 7, JP-A-8-148333, etc.).

[0003]

By the way, in the case of a structure in which the fluid pressure is controlled by a solenoid, for example, the target current is set based on the target fluid pressure, but the set load of the return spring of the solenoid varies. Therefore, even if the target current set as corresponding to the target pressure can be properly feedback-controlled, the pressure actually obtained may not match the target pressure.

If the set load adjusting mechanism is provided and the set load is adjusted to the reference value in advance, the target current is set based on the basic correlation between the drive current and the fluid pressure. Thus, the target pressure can be obtained with high accuracy, but providing a set load adjusting mechanism is disadvantageous in terms of cost, and there is a problem that the number of adjusting steps increases.

On the other hand, if the drive current corrected corresponding to the variation of the set load can be applied to the solenoid, the set pressure can be controlled to the target pressure without being adjusted to the reference value. However, in order to make the target current in the feedback control correspond to the above variation, it is necessary to change the correlation between the target pressure and the drive current for each solenoid, and the feedback control is performed according to the characteristic change of the target current. In some cases, it is necessary to change the responsiveness, etc., and if the configuration is such that the correlation between the target pressure and the drive current is changed, there is the problem that it takes a lot of man-hours to change the control specifications. there were.

The present invention has been made in view of the above problems, and the adjustment work of the set load is performed even if the correlation between the fluid pressure (or flow rate) and the drive current varies due to the variation of the set load. It is possible to obtain a target pressure (or flow rate) by feedback control to a target current, and yet to provide a solenoid drive device that can cope with characteristic variations among solenoids with a minimum change in specifications. .

[0007]

Therefore, the invention according to claim 1 provides a solenoid for adjusting fluid flow rate or fluid pressure.
Based on the control deviation between the driving current and the target current which flows in the solenoid driving device in which the feedback control of the energization control of the solenoid, the target flow rate or target pressure
Depending on the target current set according to the drive current and fluid flow rate or
Based on the value obtained by subtracting the correction value from the actual drive current of the solenoid and the target current, while setting the feedforward amount based on the value obtained by adding the correction value for correcting the variation in correlation with the fluid pressure. and configured to determine the control deviation to be used for feedback frequency setting Te.

According to this configuration, the basic target current
Is set according to the target flow rate or pressure, while
Target flow rate or pressure can be obtained according to the variation of id
As described above, correct the basic target current with the correction value
Dohoward minutes are set. On the other hand, the control deviation used for setting the feedback amount is calculated from the value obtained by subtracting the correction value from the actual drive current and the basic target current, and the correction by the correction value is performed only on the feed-forward control. Functioning and on feedback control,
Similar to the case without correction, feedback is made to the basic target current.

[0009]

According to the second aspect of the invention, the correction value is stored in advance corresponding to the target current. According to this configuration, different correction values are added for each target current, and different correction requests for each target current are met. Claim 3
In the described invention, the target current is set based on the basic correlation between the target flow rate or target pressure and the drive current corresponding to the target value, and the target flow rate or target pressure is actually obtained. The deviation between the drive current to be generated and the target current based on the basic correlation is stored in advance as a correction value for each target current.

According to this configuration, when the target flow rate or the target pressure cannot be obtained with the target current in the basic correlation, the excess / deficiency is corrected as a correction value for each target current (in other words, for each target flow rate or target pressure). ) And adding the correction value to the target current set according to the target flow rate or pressure, the drive current corresponding to the target flow rate or pressure is set as the feed forward amount.

According to a fourth aspect of the present invention, there is provided a solenoid drive device for adjusting a fluid flow rate or a fluid pressure, wherein a target current corresponding to the target flow rate or the target pressure is a basic value of the fluid flow rate or the fluid pressure and the drive current. A target current setting unit that is set based on a dynamic correlation and a table that stores a correction value corresponding to the target current, and the correction corresponding to the target current set by the target current setting unit with reference to the table. Correction value setting means for setting a value, addition correction means for adding the correction value set by the correction value setting means to the target current set by the target current setting means, and the target corrected by the addition correction means Feed forward amount setting means for setting the feed forward amount of the energization control amount of the solenoid based on the current, and a current for detecting the drive current actually flowing in the solenoid. Detection means, subtraction correction means for subtracting the correction value set by the correction value setting means from the drive current detected by the current detection means, drive current corrected by the subtraction correction means, and the target current setting means Control deviation calculating means for calculating a deviation from the target current set in step 1, feedback amount setting means for setting a feedback amount of the energization control amount of the solenoid based on the deviation calculated by the control deviation calculating means, An energization control unit that controls the drive current of the solenoid based on the energization control amount obtained by adding the feed forward amount and the feedback amount.

According to this structure, while the target current is set from the target flow rate or pressure, the correction value corresponding to the target current is obtained, and the feedforward amount is calculated based on the value obtained by adding the correction value to the target current. Is set. On the other hand, in a feedback system for feedback controlling the actual drive current of the solenoid to a target value, the correction value is subtracted from the detection result of the actual drive current, and the control deviation is calculated from the subtraction correction result and the target current. Then, the feedback amount is set in order to perform feedback control to the basic target current set as corresponding to the target flow rate or pressure.

[0014]

According to a first aspect of the present invention according to the present invention, it is possible to provide the drive current necessary to solenoid compensates for the excess or deficiency of the target current due to a variation in the set load etc., solenoid
Even if there are variations in the set load of the
While that can be controlled to the force, can be excess or deficiency causes the non basic target current in the feedback control is corrected, than Te, be carried out as it is used in feedback control of the control specification corresponding to the basic target current characteristics The effect is that you can do it.

According to the second aspect of the present invention, the target current can be corrected with a different correction value for each target current.
There is an effect that it is possible to accurately set the amount of feed forward corresponding to the target flow rate or pressure.

According to the third aspect of the present invention, the drive current that actually obtains the target flow rate or pressure is previously obtained for each solenoid, and the deviation between this drive current and the basic target current is used as the correction value. Therefore, there is an effect that the correction value corresponding to the variation of the set load of the solenoid can be accurately set. According to the invention described in claim 4, the drive current necessary for obtaining the target flow rate or the pressure can be provided by supplementing the excess or deficiency of the target current due to the variation of the set load, etc., while the excess or deficiency is not corrected. By performing the feedback control to the target current, the feedback control can be performed by using the control specifications corresponding to the basic target current characteristics as they are.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. FIG. 1 shows a hydraulic automatic transmission for a vehicle including a solenoid drive device according to the present invention. In FIG. 1, torque of an engine 1 mounted on a vehicle (not shown) is transmitted to drive wheels (not shown) via an automatic transmission 2. The automatic transmission 2 may be either a continuously variable transmission or a stepped transmission.

Further, a control device 3 (denoted as A / TC / U in the drawing) for controlling the shift of the automatic transmission 2 is
A microcomputer including a CPU, a RAM, a ROM and the like is built-in, and a plurality of solenoids for adjusting hydraulic pressures for respective friction engagement elements (clutch, brake, etc.) of the automatic transmission 2 are controlled to control a gear stage. Control automatically. The control device 3 is mounted as a unit in the ATF (automatic transmission fluid) atmosphere in the case of the automatic transmission 2 together with the plurality of solenoids.

The solenoid displaces the plunger (movable iron core) urged by the return spring by a magnetic force against the urging force of the return spring, thereby changing the opening area of the oil passage. , Which controls the hydraulic pressure supplied to each frictional engagement element, and the control device 3 determines the target hydraulic pressure and determines the target hydraulic pressure based on the correlation between the drive current i given to the solenoid and the hydraulic pressure. The drive current i corresponding to is calculated as the target current and output to the solenoid, and the energization control amount of the solenoid (for example, the on-duty of the transistor) so that the current actually flowing in the solenoid matches the target current.
Feedback control.

Specifically, with the configuration shown in FIG. 2, the energization of the solenoids is individually feedback-controlled. In FIG. 2, a target current calculation unit 51
The (target current setting means) calculates a target current corresponding to the target hydraulic pressure at that time from the correlation between the target hydraulic pressure and the drive current stored in advance.

The median value setting section 52 (feed-forward amount setting means) sets a reference duty (median value) corresponding to the target current, and this is set as a feed-forward amount (F / F).
(F correction amount). On the other hand, in the feedback correction unit 53 (feedback amount setting means), the solenoid 5
The deviation between the detected value of the current actually flowing and the target current is obtained, and the feedback amount (F / B correction amount) is output by the proportional, integral, and derivative (PID) control operation based on the deviation.

Then, for the feed forward (F / F
The result (duty) obtained by adding the correction amount) and the feedback amount (F / B correction amount) is output to a transistor (not shown) that controls the amount of electricity to the solenoid 5 (energization control means), and the transistor is the above-mentioned. Since the on / off control is performed according to the duty, the energization amount of the solenoid 5 is controlled according to the on time ratio.

The current detection of the solenoid 5 is output as a terminal voltage of a resistor provided for current detection, and the voltage is input to an A / D converter 56 via a low pass filter 55 and A / D converted. It The voltage data after A / D conversion is
It is converted into current data by the voltage-current converter 57 (current detection means). Then, the detection data of the current is
Subtraction is performed from the target current, and the deviation obtained by the subtraction processing is output to the feedback correction unit 53 as an error amount.

A correction amount setting unit 58 (correction value setting means) having a table (see FIG. 3) in which correction currents (correction values) corresponding to the target currents are stored in advance is provided.
The correction amount setting unit 58 obtains a correction current corresponding to the target current calculated by the target current calculation unit 51 by referring to the table, adds the correction current to the target current, and sets the median value. While outputting to the unit 52 (addition correction unit), the correction current is subtracted from the output of the voltage-current converter 57 (subtraction correction unit), and the detection result after the subtraction correction is calculated by the target current calculation unit 51. An error amount (control deviation) is calculated as a deviation from the set target current (control deviation calculating means).

The correction current set in the correction amount setting unit 58 is for correcting the variation in the correlation between the drive current and the hydraulic pressure due to the variation in the set load of the solenoid, and the correction current in the target current calculation unit 51. As described above, the correction current is added to the target current output to the median value setting unit 52 in order to cope with the characteristic variation of each solenoid without changing the setting characteristic of the target current. Further, if the actual current of the solenoid 5 is directly compared with the target current calculated by the target current calculation unit 51, feedback control is performed so as to match the target current calculated by the target current calculation unit 51. Since the correction by the correction current does not work, the correction current is subtracted from the detection result of the current, and the detected current value obtained by subtracting the correction current amount is compared with the target current calculated by the target current calculation unit 51. In this way, feedback control is performed using the deviation from the target current as an error amount in the same manner as when the correction by the correction current is not performed.

The table of the correction current in the correction amount setting unit 58 is set for each solenoid based on the result of actual pressure adjustment for each solenoid in the assembly line process of the automatic transmission. Specifically, the target pressure for inspection is set, the actual pressure adjusted by the solenoid is detected, and the drive current is feedback-controlled so that the target pressure is obtained. At this time, the deviation between the drive current for which the target pressure is obtained and the drive current (target current) set as corresponding to the target pressure in the target current calculation unit 51 is obtained. This process is performed for a plurality of inspection target pressures, the deviation is set as a correction current at the inspection target pressure, and a correction current that should correspond to another target current is obtained by interpolation calculation (see FIG. 3).

In the above embodiment, the solenoid used for hydraulic pressure adjustment in the automatic transmission has been described, but it may be a solenoid used for flow rate adjustment, and the applicable device is limited to the automatic transmission. Not a thing.

[Brief description of drawings]

FIG. 1 is a diagram showing a vehicle automatic transmission including a solenoid drive device according to the present invention.

FIG. 2 is a block diagram showing a solenoid drive device according to the embodiment.

FIG. 3 is a diagram showing a characteristic of a correction current (correction value) in the embodiment.

[Explanation of symbols]

1 engine 2 automatic transmission 3 control device 5 solenoid 51 Target current calculator 52 Median setting section 53 Feedback correction section 55 Low-pass filter 56 A / D converter 57 Voltage-current converter 58 Correction amount setting section

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) G05F 1/10 F16H 61/00 F16K 31/06

Claims (4)

(57) [Claims] 1. Solenoid for adjusting fluid flow rate or fluid pressure
Based on the control deviation between the drive current flowing in the drive and the target current
In the solenoid drive device configured to perform feedback control of the energization control amount of the solenoid, the target current set according to the target flow rate or the target pressure,
Compensates for variations in correlation between drive current and fluid flow rate or fluid pressure
While setting the feed forward amount based on the value obtained by adding the correction value for correction, it is used for setting the feedback amount based on the value obtained by subtracting the correction value from the actual drive current of the solenoid and the target current. A solenoid drive device configured to obtain a control deviation. Wherein said correction value, a solenoid driving device according to claim 1, wherein the stored beforehand corresponding to the target current. 3. A configuration in which the target current is set based on a basic correlation between the target flow rate or target pressure and a drive current corresponding to the target value, and the target flow rate or target pressure is actually obtained. 3. The solenoid drive device according to claim 2 , wherein a deviation between a drive current to be generated and a target current based on the basic correlation is stored in advance as a correction value for each target current. 4. A solenoid drive device for adjusting a fluid flow rate or fluid pressure, wherein a target current corresponding to the target flow rate or target pressure is set based on a basic correlation between the fluid flow rate or fluid pressure and the drive current. And a correction value for setting a correction value corresponding to the target current set by the target current setting means with reference to the table. Setting means, addition correction means for adding the correction value set by the correction value setting means to the target current set by the target current setting means, and a solenoid based on the target current corrected by the addition correction means Feed-forward amount setting means for setting the feed-forward amount of the energization control amount, current detection means for detecting the drive current actually flowing in the solenoid, and the current Subtraction correction means for subtracting the correction value set by the correction value setting means from the drive current detected by the output means, the drive current corrected by the subtraction correction means, and the target current set by the target current setting means And a feedback deviation setting means for setting a feedback quantity of the energization control amount of the solenoid based on the deviation calculated by the control deviation calculation means, the feed forward quantity and the feedback quantity. An energization control unit that controls the drive current of the solenoid based on an energization control amount obtained by adding the following, and a solenoid drive device.