JPH08148333A - Solenoid driver - Google Patents

Abstract

PURPOSE: To quickly detect abnormality of a solenoid driver. CONSTITUTION: The linear solenoid driver 100 comprises a hydraulic control valve 2 for controlling a hydraulic line pressure, being pressure fed from a hydraulic pump in order to control a vehicle, to a predetermined working pressure, a linear solenoid L for driving the hydraulic control valve 2, means 3, 4 for detecting the conduction current of the linear solenoid L, a microcomputer 1 for controlling the conduction current of the linear solenoid L, and means 40 for amplifying the output value of the microcomputer 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive device for a linear solenoid used in a control device for an automatic transmission.

[0002]

2. Description of the Related Art Conventionally, as a method for determining an abnormality in a linear solenoid that continuously changes its output value according to the amount of current supplied to the solenoid, Japanese Patent Laid-Open No. 2-180
As disclosed in Japanese Patent No. 357, there is known a method of determining a short circuit between terminals when a current value detected between terminals of a solenoid continuously exceeds a predetermined threshold value for a certain period of time.

For example, when the battery voltage is 14 V and the resistance value of the linear solenoid is 5.3 Ω, the relationship between the duty ratio value, which is the current control amount in the linear solenoid, and the current value that actually flows is shown in FIG. And the current value are in a proportional relationship that changes on a straight line L1, and areas that cannot be in a normal state apart from the current control range N are set as abnormality detection areas E1 and E2, and the power supply line to the linear solenoid is If the wire is disconnected, the current value becomes 0 (A), so the control system controls the duty ratio value to increase,
This is a method of eventually entering the abnormality detection area E1 or E2, and at that time, determining the abnormality of the drive system of the linear solenoid.

At this time, the resistance value of the linear solenoid changes in accordance with the change in environmental temperature, so that the characteristics of the duty ratio value and the current value shown in FIG. 7 change, and when the environmental temperature rises, the linear solenoid changes. The resistance value increases and moves to the straight line L2 side in the figure, and the resistance value of the linear solenoid decreases when the environmental temperature decreases, and the straight line L in the figure decreases.
Move to side 3.

[0005]

However, in this method, since the threshold value that is the reference for the abnormality determination of the drive system of the linear solenoid is uniform, the straight line L2 and the straight line L in FIG.
3 has a wide range of current values or duty ratio values that reach the abnormality detection region, and the abnormality detection region E1 or E2 must be set with a considerable margin, and therefore, the abnormality of the drive system of the linear solenoid is inevitable. At times, there is a problem in that control is performed in an abnormal state until the abnormality determination is made, that is, failsafe operation cannot be entered.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a drive device which promptly determines an abnormality of a drive system of a linear solenoid and does not control in an abnormal state.

[0007]

In order to solve the above-mentioned problems, the structure of the present invention detects the current value flowing in the solenoid and, in accordance with the deviation from the target current value, the current flowing in the solenoid in the next control cycle. In a drive device that performs feedback control of the current, the detected current follows the target current based on the current detection means for detecting the current value flowing in the solenoid and the deviation between the detected current value detected by the current detection means and the target current value. As described above, control amount calculation means for calculating the current control amount of the solenoid in the next control cycle, and energization control means for controlling the value of the current flowing through the solenoid based on the current control amount calculated by the control amount calculation means. Regarding the current control amount, the abnormality detection area setting that sets a large value range that does not occur in normal operation as the abnormality detection area Means and a reference value setting means for setting a reference value for the current control amount that is smaller than the lower limit value of the abnormality detection region by a predetermined value, and the current control amount is in the range of the reference value or more and less than the lower limit value of the abnormality detection region. If you do
When the current control amount in the next control cycle is forcibly changed to the lower limit value instead of the current control amount calculated by the control amount calculation means, and the current control amount exists in the abnormality detection area Has an abnormality processing means for performing abnormality processing.

According to the second aspect of the invention, in the drive device for detecting the current value flowing in the solenoid and performing feedback control of the current flowing in the solenoid in the next control cycle in accordance with the deviation from the target current value, the solenoid is used. Based on the deviation between the current detection means for detecting the flowing current value and the detected current value detected by the current detection means and the target current value, so that the detected current follows the target current, the solenoid of the next control cycle Control amount calculation means for calculating the current control amount, energization control means for controlling the value of the current flowing through the solenoid based on the current control amount calculated by the control amount calculation means, and normal operation with respect to the current control amount There is a difference between the current control amount and the abnormality detection area setting means that sets a small value range that cannot be taken Reference value setting means for setting a reference value that is larger than the upper limit value of the detection area by a predetermined value, and if the current control amount is within the reference value and higher than the upper limit value of the abnormality detection area, the next control cycle In place of the current control amount calculated by the control amount calculation means, the current control amount is forcedly changed to the upper limit value, and if the current control amount exists in the abnormality detection area, And an abnormality processing means for performing processing.

The configuration of the third invention is characterized in that the current control amount is a duty ratio of a current flowing through the solenoid.

According to a fourth aspect of the present invention, with respect to the current control amount, a fail safe region setting means for setting a range from a value larger than the reference value to the lower limit value of the abnormality detection region as a fail safe region, and the current control amount fails. When it exists in the safe area, it is characterized by further comprising a fail-safe processing means for performing a fail-safe processing before performing the abnormal processing.

A fifth aspect of the present invention relates to a fail-safe area setting means for setting a range from a value smaller than a reference value to an upper limit value of the abnormality detection area as a fail-safe area, and a current-controlled quantity in a fail-safe area. In the case of the above, it further comprises a fail-safe processing means for performing a fail-safe processing before performing the abnormal processing.

[0012]

[Operation and effect] When the current control amount becomes equal to the reference value during normal operation, the current control amount in the next control cycle is not the control amount determined by the feedback control, but is forced to the lower limit of the abnormality detection area. Is changed to. That is, the control amount is increased stepwise. As a result, in the next control cycle, the actual current increases, the detected current value also increases, and the deviation of the detected current value from the target current value increases in the positive direction. The control amount becomes small. Then, the current control amount becomes smaller than the reference value, and the current control amount is not forcibly changed by the control amount changing means, and the feedback control in the normal operation is restored in the next control cycle. As a result, the current control amount does not exceed the reference value.

On the other hand, when the current control amount becomes equal to the reference value during abnormal operation due to, for example, disconnection, the current control amount in the next control cycle is the control amount determined by the feedback control, as in the normal state. Instead, it is forcibly changed to the lower limit of the abnormality detection area. However, in the abnormal state, unlike the normal state, the actual current does not increase even in the next control cycle. Therefore, the detected current value does not increase,
The deviation of the detected current value from the target current value is still
Since it is a large negative absolute value, the current control amount calculated by the control amount calculation means further increases than the value determined in the previous control cycle. Then, since the current control amount further exceeds the reference value, the control amount changing means also forcibly changes the current control amount to the lower limit value of the abnormality detection range in the next control cycle. After all, as a result of repeating the above-described processing, the current control amount is held at the lower limit value. After that, the current control amount calculated by the control amount calculation means, that is, the current control amount determined by the feedback control, exceeds the lower limit value of the abnormality detection region, and the abnormality processing is executed.

When the current control amount becomes equal to the reference value during an abnormal operation due to, for example, a short circuit, the current control amount in the next control cycle is the control amount determined by the feedback control as in the normal state. Instead, it is forcibly changed to the upper limit of the abnormality detection area. However, in the abnormal state, unlike the normal state, the actual current does not decrease even in the next control cycle. Therefore, the detected current value does not decrease,
The deviation of the detected current value from the target current value is still
Since it is a large positive absolute value, the current control amount calculated by the control amount calculation means is further reduced than the value determined in the previous control cycle. Then, the current control amount will be lower than the reference value, and therefore, in the next control cycle as well, the current control amount is forcibly changed to the upper limit value of the abnormality detection range by the control amount changing means. After all, as a result of repeating the above-described processing, the current control amount is held at the upper limit value. After that, the current control amount calculated by the control amount calculation means, that is, the current control amount determined by the feedback control becomes lower than the upper limit value of the abnormality detection region, and the abnormality processing is executed.

In this way, the time taken for the current control amount to reach the abnormality detection region is shortened, and abnormality detection is performed at high speed.
Also, in the event of a failure such as a wire break or short circuit, by setting the fail-safe area before the abnormality detection area, the output is turned off as fail-safe processing before the abnormality detection processing, and control is performed without a linear solenoid. Therefore, the quality of the solenoid drive device can be further improved without performing control in an abnormal state.

[0016]

EXAMPLES The present invention will be described below based on specific examples. FIG. 1 is a block diagram showing a linear solenoid drive device 100. Linear solenoid drive device 10
0 is, for example, a hydraulic control valve 2 and a hydraulic control valve that control a vehicle control line hydraulic pressure (transmission hydraulic pressure for automatic transmission control, etc.) pumped from a hydraulic pump driven by an internal combustion engine to a predetermined operating hydraulic pressure. The output values of the linear solenoid L for driving 2, the current detection means 3 and 4 for detecting the energization current of the linear solenoid L, the microcomputer 1 for controlling the energization current of the linear solenoid L, and the microcomputer (hereinafter referred to as the microcomputer) 1 It is composed of amplification means 40 for amplifying.

Next, the operation of the linear solenoid drive device 100 will be described. The microcomputer 1 stores in advance the relationship between the control position and the target current value in a predetermined environment, compares the current value detected by the current detecting means 3 and 4 with the target current value corresponding to the control position, Output is performed with feedback so that the detected value follows the target value. The output from this microcomputer 1 is output terminal 1-1 in the figure.
And the output is amplified by the amplification means 40,
It is supplied to the linear solenoid L.

The energization output of the linear solenoid L can be controlled by changing the duty ratio value.
The current value flowing through the linear solenoid L is the current detection means 3
It is detected as the voltage across the current detection resistor RS therein. The voltage across the current detection resistor RS is amplified by the amplification means 30 and further integrated by the integration means 20,
The average current of the currents flowing through the linear solenoid is taken into the AD converter 10 as a voltage value. Microcomputer 1 is A
The voltage value is read from the D converter 10 at any time, and the duty ratio value output to the linear solenoid L is corrected based on the voltage value.

Now, a method for determining an abnormality of the linear solenoid drive device 100 according to this embodiment will be described. The present invention relates to the abnormality determination of the linear solenoid drive device 100, and in addition to the abnormality detection areas E1 and E2 that have been conventionally set in the relationship between the duty ratio value and the current value, the fail safe area F1 is provided in the adjacent area. Set up F2,
The schematic diagram is shown in FIG.

When the characteristic of the linear solenoid L reaches a predetermined first reference value a'before the fail-safe area F1 on the straight line L0, the duty ratio value is changed to the abnormality detection area E.
It increases to the lower limit value b of 1. If the linear solenoid drive device 100 is normal, the duty ratio value or the current value is controlled in the fail-safe region F1 because the duty ratio value is controlled to decrease by the current feedback.
It does not enter the abnormality detection area E1.

When the linear solenoid drive device 100 is abnormal, for example, when the wire is broken, even if the duty ratio value is increased to the lower limit value b of the abnormality detection area E1, it still works in the direction of increasing the duty ratio value. First, the duty ratio value or the current value enters the fail safe area F1.
Eventually, the abnormality detection area E1 is entered, and the abnormality determination of the linear solenoid drive device 100 can be performed.

The above-described abnormality determination method will be described with reference to the flowchart shown in FIG. First, in step 200, a deviation Δ between the target current value I and the detected current value i is calculated, and the deviation Δ is used to calculate an actual output duty ratio value TDUTY in the following step 210, and the process proceeds to step 220. Here, k and h in the figure represent a proportional term coefficient and an integral term coefficient, respectively.

In step 220, the duty ratio value DUTY (output duty buffer RAM for abnormality determination) obtained from the detected current value i is compared with a predetermined first reference value a '(%) in FIG. Duty ratio value DUT
If Y is greater than or equal to the first reference value a '(%), step 23
0, the duty ratio value DUTY and the abnormality detection lower limit value b
(%) Is compared with the size. When the duty ratio value DUTY is smaller than the first reference value a ′ (%) in step 220, the process proceeds to step 310 of FIG.

At step 230, the duty ratio value DU
When TY is smaller than the abnormality detection lower limit value b (%), the routine proceeds to step 240, where the actual output duty ratio value TDUTY is set as the abnormality detection lower limit value b (%). Here, if the linear solenoid drive device 100 is normal, the duty ratio value decreases, so that it does not enter the fail-safe area F1.
The duty ratio value DUTY is the fail safe lower limit value a.
Since it is smaller than (%), NO is determined in step 260, and the process returns in step 280.

When the linear solenoid drive device 100 is abnormal, the duty ratio value does not decrease and enters the fail safe region F, so that the duty ratio value DUTY becomes larger than the fail safe lower limit value a (%), and step 260 is executed. Is determined to be YES, the process proceeds to step 270, the fail-safe process of cutting off the energization of the linear solenoid L is performed, and the process returns to step 280. In step 230, when the duty ratio value DUTY is greater than or equal to the abnormality detection lower limit value b (%), it is considered that the linear solenoid drive device 100 is abnormal, the process proceeds to step 290, and the linear safe process performed in step 270 is performed. The energization cut of the solenoid L is maintained, and an abnormality detection process such as lighting of a warning lamp is performed.

A schematic representation of the above operation is shown in FIG. The solid line and the broken line in the figure show the actual output duty ratio value TDUTY and the duty ratio value DUTY, respectively (a)
Shows the time history when the drive system is normal, and (b) shows the time history when the drive system is abnormal. When the drive system is normal, if the actual output duty ratio value TDUTY is momentarily raised to the abnormality detection lower limit value b when the duty ratio value DUTY reaches the first reference value a ′, immediately after that, the duty ratio value Although DUTY increases, it decreases immediately because the control works, and gradually decreases.

When the drive system has an abnormality due to disconnection, when the duty ratio value DUTY reaches the first reference value a ', the actual output duty ratio value TDUTY is instantaneously raised to the abnormality detection lower limit value b. Does not work, the duty ratio value DUTY reaches the abnormality detection lower limit value b, and the abnormality of the linear solenoid drive device 100 is detected. In the present embodiment, the processing flow of the abnormality determination of the linear solenoid drive device 100 based on the duty ratio value DUTY is shown, but the abnormality detection of the drive system may be performed by the current detection value i of the linear solenoid L.

Similarly, on the straight line L0 in FIG. 2, when the characteristic of the linear solenoid L reaches a predetermined second reference value c'before the fail-safe area F2, the duty ratio value is changed to the abnormality detection area E2. To the upper limit value d. If the linear solenoid drive device 100 is normal, the duty ratio value or the current value does not enter the fail safe region F2 or the abnormality detection region E2 because the duty ratio value is controlled to increase by the current feedback. .

In the case where the linear solenoid drive device 100 is abnormal due to a short circuit, even if the duty ratio value is reduced to the upper limit value d of the abnormality detection area E2, the duty ratio value still works in the decreasing direction. Alternatively, the current value first enters the fail-safe area F2 and then enters the abnormality detection area E2, and the linear solenoid drive device 100
It is possible to determine the abnormality.

The above-described abnormality determination method will be described with reference to the flowchart shown in FIG. Step 310
Then, the duty ratio value DUTY is compared with a predetermined second reference value c ′ (%) in FIG.
If UTY is equal to or less than the first reference value c ′ (%), the routine proceeds to step 320, where the duty ratio value DUTY and the abnormality detection upper limit value d (%) are compared in magnitude. When the duty ratio value DUTY is larger than the second reference value c '(%) in step 310, the process proceeds to step 380, and the actual output duty ratio value TDUTY is output.

At step 320, the duty ratio value DU
When TY is larger than the abnormality detection upper limit value d (%), the routine proceeds to step 330, where the actual output duty ratio value TDUTY is set as the abnormality detection upper limit value d (%). Here, if the linear solenoid drive device 100 is normal, the duty ratio value increases, so it does not enter the fail-safe area F2.
The duty ratio value DUTY is the fail safe upper limit value c.
Since it is larger than (%), NO is determined in step 350, and the process returns in step 370.

When the linear solenoid drive device 100 is abnormal, the duty ratio value does not increase and enters the fail safe region F2, so the duty ratio value DUTY becomes smaller than the fail safe upper limit value c (%), and step 350
Is determined to be YES, the process proceeds to step 360, the fail-safe process of cutting the energization of the linear solenoid L is performed, and the process returns to step 370. In step 320, when the duty ratio value DUTY is equal to or less than the abnormality detection upper limit value d (%), it is considered that the linear solenoid drive device 100 is abnormal, the process proceeds to step 390, and the linear process performed in the fail-safe process of step 360 is performed. The energization cut of the solenoid L is maintained, and an abnormality detection process such as lighting of a warning lamp is performed.

A schematic representation of the above operation is shown in FIG. The solid line and the broken line in the figure show the actual output duty ratio value TDUTY and the duty ratio value DUTY, respectively (a)
Shows the time history when the drive system is normal, and (b) shows the time history when the drive system is abnormal. When the drive system is normal, if the actual output duty ratio value TDUTY is momentarily reduced to the abnormality detection upper limit value d when the duty ratio value DUTY reaches the second reference value c ′, immediately after that, the duty ratio value Although DUTY decreases, it immediately increases and gradually decreases due to the control.

When the drive system has an abnormality due to a short circuit, when the duty ratio value DUTY reaches the second reference value c ', the actual output duty ratio value TDUTY is instantaneously lowered to the abnormality detection upper limit value d. Does not work, the duty ratio value DUTY reaches the abnormality detection upper limit value d, and the abnormality of the linear solenoid drive device 100 is detected. At this time, the processing flow of the abnormality determination of the linear solenoid drive device 100 based on the duty ratio value DUTY is shown, but the abnormality detection of the drive system may be performed by the current detection value i of the linear solenoid L.

As indicated above, according to the present invention,
When fail-safe areas F1 and F2 are provided in areas adjacent to the abnormality detection areas E1 and E2 of the linear solenoid L, and when the duty ratio value DUTY reaches a predetermined first reference value a ′ before the fail-safe area F1. , Forcibly set the actual output duty ratio value TDUTY to the abnormal detection lower limit value b (%)
By instantaneously increasing the duty ratio value DUTY to the predetermined second reference value c ′ before the fail-safe region F2, the actual output duty ratio value TDUTY is forcibly detected by the abnormality detection upper limit. By instantaneously reducing the value to the value d (%), the abnormality of the drive system can be detected at a higher speed, and the linear solenoid drive device 100
The quality of can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of a linear solenoid drive device according to the present invention.

FIG. 2 is an explanatory diagram showing a relationship between an abnormality determination area and a fail-safe area.

FIG. 3 is a flowchart showing a processing procedure of abnormality detection due to disconnection of a linear solenoid drive device.

FIG. 4 is a flowchart showing a processing procedure of abnormality detection due to a short circuit of a linear solenoid drive device.

FIG. 5 is a schematic diagram showing a time history of duty ratio values when the linear solenoid drive device according to the present invention is normal (a) and when it is abnormal due to disconnection (b).

FIG. 6 is a schematic diagram showing a time history of duty ratio values when the linear solenoid drive device according to the present invention is normal (a) and when it is abnormal due to a short circuit (b).

FIG. 7 is a schematic diagram showing a conventional method for determining an abnormality of a linear solenoid.

[Explanation of symbols]

 L linear solenoid 1 microcomputer (microcomputer) 1-1 output terminal 2 hydraulic control valve 3, 4 current detection means 10 AD converter 20 integration means 30, 40 amplification means 100 linear solenoid control device F1, F2 fail-safe area E1, E2 Abnormality detection area N Current control range RS Current detection resistance a Fail safe lower limit value b Abnormality detection lower limit value a'First reference value c Fail safe upper limit value d Abnormality detection upper limit value c'Second reference value I Target current value i Detected current Value DUTY Duty ratio value TDUTY Actual output duty ratio value k Proportional term coefficient h Integral term coefficient

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Claims (5)

[Claims] 1. A drive device for detecting a current value flowing through a solenoid and feedback controlling the current flowing through the solenoid in the next control cycle in accordance with a deviation from a target current value. The current detecting the current value flowing through the solenoid. Based on the deviation between the detection means and the detected current value detected by the current detection means and the target current value, the current control amount of the solenoid in the next control cycle is calculated so that the detected current follows the target current. Control amount calculation means, energization control means for controlling the value of the current flowing through the solenoid based on the current control amount calculated by the control amount calculation means, and the current control amount for normal operation With regard to the current control amount, an abnormality detection area setting means for setting a range of a large value as Reference value setting means for setting a reference value that is smaller than the lower limit value of the abnormality detection region by a predetermined value, and if the current control amount is greater than or equal to the reference value and smaller than the lower limit value of the abnormality detection region. Is a control amount changing unit for forcibly changing the current control amount in the next control cycle to the lower limit value instead of the current control amount calculated by the control amount calculation unit, and the current control amount is A solenoid drive device having an abnormality processing means for performing abnormality processing when the solenoid drive device exists in the abnormality detection region. 2. A drive device for detecting a current value flowing through a solenoid and feedback-controlling the current flowing through the solenoid in the next control cycle in accordance with a deviation from a target current value. Based on the deviation between the detection means and the detected current value detected by the current detection means and the target current value, the current control amount of the solenoid in the next control cycle is calculated so that the detected current follows the target current. Control amount calculation means, energization control means for controlling the value of the current flowing through the solenoid based on the current control amount calculated by the control amount calculation means, and regarding the current control amount, in normal operation With respect to the current control amount, an abnormality detection area setting unit that sets a range of a small value that does not exist as an abnormality detection area Reference value setting means for setting a reference value that is larger than the upper limit value of the abnormality detection region by a predetermined value, and the current control amount is equal to or less than the reference value and is in a range larger than the upper limit value of the abnormality detection region. The current control amount in the next control cycle, in place of the current control amount calculated by the control amount calculation means, the control amount changing unit forcibly changing to the upper limit value, the current control amount is A solenoid drive device having an abnormality processing means for performing abnormality processing when the solenoid drive device exists in the abnormality detection region. 3. The current control amount is a duty ratio of a current flowing through the solenoid.
Alternatively, the solenoid drive device according to claim 2. 4. A fail-safe region setting means for setting a range from a value larger than the reference value to the lower limit value of the abnormality detection region as a fail-safe region for the current control amount, and the current control amount being the fail. The solenoid drive device according to claim 1, further comprising: fail-safe processing means for performing fail-safe processing before performing abnormal processing when the solenoid drive exists in the safe area. 5. With respect to the current control amount, a fail safe region setting means for setting a range from a value smaller than the reference value to the upper limit value of the abnormality detection region as a fail safe region, and the current control amount is the fail control region. The solenoid drive device according to claim 2, further comprising: fail-safe processing means for performing fail-safe processing before performing abnormality processing when the solenoid drive exists in the safe area.