JP2003148156A - Device for controlling motor position of turbocharger, and method for controlling motor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for controlling a motor position preventing displacement of a motor of a position control device using a motor. SOLUTION: This control device is constituted by a CPU, a peripheral circuit thereof and an I/F circuit to the outside, controls at least a motor driver by target opening degree signals inputted from the outside for rotating the motor, opens or closes a passage of an intake air induction path of a turbocharger of an automobile by the output of the rotary shaft of the motor, and adjusts the supercharged pressure of the turbocharger. Also, this motor position control device compares output signals of a motor rotation position detecting device installed to the output shaft of the motor with target opening degree signals, and controls the motor position in a manner to equalize two kinds of signals. In this device, a motor operation is initialized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a controlled object at a target position by using a mechanical portion of a DC motor.

[0002]

2. Description of the Related Art In order to eliminate the influence of noise generated in an encoder when a motor position is detected by using two encoders, Japanese Patent No. 3039512 discloses that a signal of one encoder should rise or fall. A method for eliminating the influence of noise by measuring the other signal after a fixed time after detection is described.

[0003]

However, according to the method disclosed in Japanese Patent No. 3039512,
It is not possible to eliminate false counts at all. That is, it is necessary to prevent the deviation of the control position of the motor from being accumulated more and more due to incorrect counting. Further, even in the case of a device in which a potentiometer or the like is attached to the output shaft of the motor to detect the operating position of the actuator, it is necessary to grasp the fully closed position and the fully opened position, so the initialization operation is necessary.

An object of the present invention is to provide a motor position control device capable of further preventing motor position shift of a position control device using a motor.

[0005]

SUMMARY OF THE INVENTION A motor is controlled by a motor driver controlled by a target opening signal input from at least the outside, which is composed of a CPU, a peripheral circuit thereof and an external I / F circuit, and a rotary shaft of the motor. The output signal of the control device for opening and closing the passage of the intake air introduction path of the turbocharger of the automobile to adjust the boost pressure of the turbocharger, and the output signal of the motor rotation position detection device provided on the output shaft of the motor, and the output signal In the motor position control device that controls the motor position so that they are compared with the target opening signal so that they match, the initialization of the motor operation (operation to the fully open position and the fully closed position within the motor control operation range, or either One operation) is performed.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the configuration of an embodiment.

The blade angle in the turbocharger is changed via a gear provided on the output shaft of the motor to change the boost pressure of the turbocharger 1.

In addition to the gear, the worm gear 7 is provided with a rotary encoder 3 for detecting the rotational position of the motor.

In this embodiment, two incremental encoders are used.

The encoder 3 is provided with a Hall element 4 for converting the rotational position into a signal, and the rotational position of the encoder is converted into a signal and input to the control device 5.

FIG. 3 shows a signal waveform from the encoder described above.

The ΦA signal and the ΦB signal are out of phase with each other by 90 degrees. For example, the direction of rotation of the motor can be known by looking at the level of the ΦB signal when the ΦA rises or falls, and the pulse number of the signal is counted. It is possible to detect the rotational position of the motor. On the other hand, the control target position signal 6a of the turbocharger motor rotation position (rotor blade angle in the turbocharger) is input from the other control device 6 to the control device 5, and the control device 5 makes the control target position signal 6a equal to the rotation position of the motor. In this system, the signal 5a for driving the motor 2 is output so that the rotational position of the motor 2 is controlled according to the control target position signal 6a.

In this embodiment, the controller 5 and the other controller 6
Although they are separated, the same function can be obtained by integrating both.

The rotary encoder 3 is attached to the rotary shaft of the worm gear 7 for detecting the rotational position of the motor. Alternatively, a potentiometer is attached to the rotary shaft of the gear 2c to directly measure the rotational angle of the gear 2c and the turbocharger. It is also possible to control the inner rotor blade angle according to the control target position signal. It is also possible to use an absolute type encoder instead of the potentiometer.

FIG. 2 shows an internal block diagram of the control device 5 of this embodiment.

CPU 9 (Central Processing Unit), I
/ O8 (Input / Output), A / D14 (Analog to Digital
converter), RAM15 (Random Access Memory),
ROM 16 (Read Only Memory), non-volatile memory 1
7, a motor driver 10, and a communication driver 13, and in the case of the present embodiment, a control signal to the motor driver 10 so that the target opening signal 11b input to the I / O and the rotational position signal 11a of the motor become equal. 9a
Is output.

The CPU 9 has a function of reading a control arithmetic expression from the ROM 16 and holding the calculated value in the RAM 15.

The non-volatile memory is used when it is desired to retain the above-mentioned calculation data and the like even after the power of the control unit is turned off, and may be omitted if there is no data to be retained.

The CPU also has a function of exchanging data with the outside through the communication driver 13, and the same function is provided even if the target opening signal is input to the CPU 9 through the communication driver 13. I can do things.

When a potentiometer is used, the signal is analog data, and the gear position is detected via the A / D 14.

In this control device, initialization is first carried out to detect the motor position.
First, since the position of the first motor is not known by the control device, it is necessary to rotate the motor in either direction to operate it until it is mechanically locked. In this case, since the gears are used for driving, if the motor is rotated at a speed higher than a certain value, the gear will be caught when it hits the stopper, and even if it sticks and is reversed at maximum torque, it will get caught. The drive speed must be such that the above gears do not get caught during the initializing operation.The rotation direction of the motor should be set during protection of the turbocharger and engine and during normal operation. When doing it, it should be done in the direction of lowering the boost pressure on the safe side. FIG. 4 shows the operation logic at the time of initialization.

FIG. 4-A shows that the encoder pulse signal starts to change when the motor is rotated at a constant speed equal to or lower than the motor speed C at which mechanical biting occurs, and the state in which the signal does not change continues for a certain time or longer. This is the logic for determining the stopper position at the time point, and FIG. 4-A- (1) shows the state of the motor speed with respect to the change of the encoder pulse.

FIG. 4B has the same purpose, but the motor speed is not a constant value, but is started from 0 and gradually increased, and the mechanical resistance is increased within the operating range. This is an effective method when there is.

In FIG. 4-C, when the resistance portion is reached as compared with FIG. 4-B, the motor is returned in the opposite direction at least once and then the force is passed to pass the mechanical resistance portion. And is a more effective method.

Next, an embodiment of a method for performing initialization during normal operation will be described.

After completion of initialization when the power of the control device is turned on, the control is shifted to normal control, and the motor position is controlled according to the target opening signal input from the outside. This control device is for turbo control. Therefore, there are modes that have little effect on the control even during normal control, such as when the engine is idling and the boost pressure is low, when the engine load is low, and when the accelerator opening is small. In addition, there is a case where an initialization execution command or the like is input from the outside.

When the method of detecting the rotation direction and the position of the motor by the encoder is used, there is a case where the rotation position detection position of the motor cannot be obtained when noise is mixed in the signal of the encoder.

FIG. 5 shows an example of this.

FIG. 5A shows the waveform of the encoder in the normal case.

The following method is generally used as a motor position detection method using an encoder.

When the encoder signal ΦA rises, the encoder signal ΦB is Low level, and the encoder signal ΦA
Encoder signal ΦB at the falling edge of the signal is High
Similarly, when the encoder signal ΦA at the rising edge of the encoder signal ΦB is at the high level and the encoder signal ΦA at the falling edge of the encoder signal ΦB is at the low level, it is determined to be normal rotation and the counter is incremented.

In the case of inversion, the pattern is the reverse of that described above. In this case, the counter is downed. With this logic, the position of the motor can be detected with a resolution of ¼ cycle of the encoder pulse.

FIG. 5B shows an example in which noise is mixed in the encoder .PHI.A and misalignment occurs due to rising and falling of noise, resulting in misalignment.

In the method of detecting the rotational position of the motor by using the encoder as shown in this figure, if noise or the like is mixed in the encoder signal, erroneous counting may occur and the detected position may be displaced.

In order to prevent this displacement, a logic for determining whether the encoder signal is a normal signal or noise may be provided. However, when the logic processing requires time and the encoder signal period is short. In some cases, the processing may not be completed and the signal processing may be adversely affected.

For this reason, in this embodiment, the power source O
The initialization operation is performed even during the normal control other than N time and OFF time to cancel the positional deviation and prevent the positional deviation from being integrated.

Next, an embodiment in the case where the initialization operation is performed during the normal control will be described.

Various conditions can be considered for the initialization during the normal control, but in the example using FIG. 7, the target opening signal is smaller than the constant value E and the change of the target opening signal continues for a constant value F or more. The case of time is shown.

When the value of the target opening signal is smaller than the low boosting pressure state E that does not affect the engine during the normal operation and there is no change in the target opening signal for the time F or more, the normal operation state is set. Perform the initializing operation.

During the initialization operation, the initialization flag is regularly monitored, and when the initialization is prohibited (the initialization flag is cleared) due to the change of the target opening during the initialization operation, the normal control is restored at that time. ing.

At the time of returning to the normal control, if the motor position is larger than the difference between the old position before the initialization and the target value, there is a problem that the operation is delayed by performing the initialization. In the state, it is necessary to increase the operation speed of the motor so that no operation delay occurs.

FIG. 7 shows an embodiment, and when the conditions for executing the initialization in the normal state depend on the accelerator opening and the boost pressure of the turbocharger, the number of times the motor has been operated and the operating time since the initialization was carried out last time. It is conceivable that the above method or the like, or the combination of these conditions may be used.

As described above, by performing the initialization during the normal operation, it is possible to cancel the deviation of the motor position due to the variation of the position accuracy of the motor and the accumulation of erroneous counts.

Further, since the turbocharger is directly connected to the exhaust pipe of the engine, it is always exposed to high temperature conditions, and the mechanical components of the variable blades for varying the intake air amount of the turbocharger are easily deteriorated. The mechanical resistance component also tends to gradually increase unless it is operated frequently.

Therefore, in order to reduce the operating resistance of the mechanical portion, the initialization should be carried out. By performing the initialization, the resistance of the mechanical portion can be prevented from increasing and the durability of the mechanical portion can be improved and the drive motor can be improved. Since the burden is reduced, the durability of the motor can be improved.

As described above, according to the embodiment, it is possible to prevent the displacement of the motor of the position control device using the motor. Further, the durability of the control device can be improved.

[0047]

According to the present invention, it is possible to provide a motor position control device capable of further preventing the displacement of the motor of the position control device using the motor.

[Brief description of drawings]

FIG. 1 is a system diagram of a motor control device.

FIG. 2 is a block diagram of a motor control device.

FIG. 3 is a signal of a motor position detection encoder.

FIG. 4-A is an example of an initialization process.

FIG. 4-A- (1) is an example of an initialization process.

FIG. 4-B is an example of an initialization process.

FIG. 4-B- (1) is an example of initialization processing.

FIG. 4-C is an example of an initialization process.

FIG. 4-C- (1) is an example of initialization processing.

FIG. 5-A is a motor position counting method using an encoder.

FIG. 5-B is a motor position counting method using an encoder.

FIG. 6 shows an initialization sequence in normal time.

FIG. 7 shows a normalizing process at a normal time.

FIG. 8 is an operating resistance characteristic of a mechanical part.

[Explanation of symbols]

1 ... Turbocharger, 1-a ... Variable blade, 2 ... Motor,
2a, 2b, 2c ... Gear, 3 ... Encoder, 4 ... Hall element, 4a ... Encoder pulse, 5 ... Control device, 6 ... Other control device, 6a, 11b ... Target opening signal, 6b ... Communication signal, 7 ... Worm gear, 8 ... I / O, 9 ... CPU, 1
0 ... motor driver, 11a ... motor rotation position signal I,
11c ... IGN signal, 13 ... Communication driver, 14 ... A / D, 15 ... RAM, 16 ... ROM, 17
... non-volatile memory.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shoji Sasaki             Hitachinaka City, Ibaraki Prefecture 2520 Takaba             Ceremony Company Hitachi Ltd. Automotive equipment group (72) Inventor Hiroaki Saeki             2477 Takaba, Hitachinaka City, Ibaraki Prefecture Stock Association             Inside Hitachi Car Engineering (72) Inventor Masayuki Suga             Hitachinaka City, Ibaraki Prefecture 2520 Takaba             Ceremony Company Hitachi Ltd. Automotive equipment group F term (reference) 3G005 EA15 FA23 GA04 GB25 GC08                       GD13 JA06 JA31                 3G071 AB06 BA11 BA22 CA09 EA01                       FA07

Claims (19)

[Claims] 1. An I / F for a CPU, its peripheral circuits and the outside.
The motor driver is controlled by at least the target opening signal input from the outside, which is composed of a circuit, to rotate the motor, and the rotation shaft output of the motor causes the passage of the intake air introduction path of the turbocharger of the automobile to be opened and closed. A motor that controls the motor position so that the control device that adjusts the pressurizing pressure and the output signal of the motor rotation position detection device that is provided on the output shaft of the motor and the target opening signal are compared and they match. A motor position control device characterized by performing initialization of a motor operation (operation to a fully open position and a fully closed position within a motor control operation range, or one of the operations) in a position control device. 2. The initializing operation described in claim 1 is to operate at a constant speed at a speed at which mechanical biting does not occur and to operate until it hits a stopper, and to rotate for initializing. The direction of the motor is at least the direction in which the boost pressure of the turbocharger is lowered, and when the state in which the signal from the motor position detection device does not change continues for a certain period of time, that position is determined to be the stopper position of the control device. Motor position control device. 3. The initializing operation described in claim 1 is performed at a speed at which mechanical entrapment does not occur, at least initially, starting from 0 and gradually increasing until it hits a stopper. Yes, and the direction of the motor rotated for initialization is at least the direction of decreasing the boost pressure of the turbocharger, and if the signal from the motor position detector does not change for a certain period of time, the position is stopped by the stopper of the controller. A motor position control device characterized by determining a position. 4. The initializing operation according to claim 1 is performed at a speed below a speed at which mechanical biting does not occur, at least initially, starting from 0 and gradually increasing until reaching a stopper. In addition, the direction of the motor rotated for initialization is at least the direction of lowering the boost pressure of the turbocharger, and at least once once if the signal from the motor position detection device remains unchanged for a certain period of time. Return to the intermediate position from the start position or the initialization start position to the current position in the reverse direction, operate again toward the stopper position at the same speed, and hit the stopper and the signal from the motor position detector does not change for a certain period of time. In addition, the position is determined to be the stopper position of the control device. Motor position controller. 5. The initialization operation of the motor according to claim 1 is externally input via an input / output I / F circuit, an A / D input circuit, or an external input via a communication circuit. Among the external input signals, the motor position control device is operated at least when the power is turned on, or when the IGN signal is turned on or when the IGN signal is turned off. 6. The initializing operation of the motor operation according to claim 1 is input from the outside via an input / output I / F circuit, an A / D input circuit, or a communication circuit. It is a signal of the accelerator opening position of the engine among the external input signals, and is characterized in that it is performed at least once in a normal control state and when the accelerator opening position has exceeded a certain value for a certain time or more. And a motor position control device. 7. The initializing operation of the motor position control device is canceled during normalizing operation of the motor position during normal control, and the initializing operation is stopped by a factor such as a change of the target opening position signal. A motor position control device characterized in that, when it is necessary to restore the motor, the operation speed of the motor is changed and the delay of the operation response time caused by switching from the initialization operation to the normal control is eliminated. 8. The initializing operation of the motor operation according to claim 1 is externally input via an input / output I / F circuit, an A / D input circuit, or an external input via a communication circuit. At least the engine speed, the accelerator opening signal, the idle determination signal, and the table value of the load state among the external input signals that can be used to determine the load state of the engine. From these signals, the engine load is smaller than a certain value. A motor position control device characterized in that initialization is performed at least once when the state continues for a certain period of time. 9. The initialization operation of the motor operation according to claim 1 is externally input via an input / output I / F circuit, an A / D input circuit, or an external input via a communication circuit. Of the external input signals that are output, it is based on at least the signal that shows the elapsed time since the power was turned on, and the initialization is permitted at least once if a certain time has elapsed after the previous initialization. And a motor position control device. 10. The initializing operation of the motor operation according to claim 1 is externally input via an input / output I / F circuit, an A / D input circuit, or an external input via a communication circuit. Of the external input signals that are output, it is a signal that can determine at least the traveling distance of the vehicle.If the vehicle has been traveling a certain distance since the last initialization, the initialization should be permitted at least once. A motor position control device. 11. The initialization operation of the motor operation according to claim 1 counts the opening / closing operations of the motor above a certain value, and the number of opening / closing operations of the motor position is more than a certain value since the previous initialization operation was performed. If
A motor position control device characterized by permitting execution of initialization at least once. 12. The initialization operation of the motor operation according to claim 1 is externally input via an input / output I / F circuit, an A / D input circuit, or an external input via a communication circuit. Of the external input signals that are generated, at least the booster pressure signal of the turbocharger must be permitted at least once during normal control and when the booster pressure of the turbocharger remains below a certain value for a certain period of time. A motor position control device. 13. The initialization operation of the motor operation according to claim 1 is at least an initialization permission signal among external input signals input from the outside through a communication circuit, and at least one of them is input at the time of inputting the initialization permission signal. A motor position control device characterized by permitting a circular initializing operation. 14. The initializing operation of the motor operation according to claim 1 is externally input via an input / output I / F circuit, an A / D input circuit, or an external input via a communication circuit. A motor position control device which permits an initialization operation at least once when it is determined that the motor position control device has failed due to an external input signal. 15. The initializing operation of the motor operation according to claim 1 has a movable range narrower than a normal control range due to an increase in mechanical resistance or the like based on a signal from a motor position detecting device of a control device. A motor position control device characterized by permitting an initializing operation at least once when it is judged that the motor position has been exceeded. 16. A CPU, its peripheral circuits, and an external I / I.
The motor driver is controlled by at least the target opening signal input from the outside, which is configured by the F circuit, to rotate the motor, and the output of the rotation shaft of the motor causes the passage of the intake air introduction path of the turbocharger of the automobile to be opened and closed. In the control device that adjusts the pressurizing pressure, the mechanical lock operation is prevented by increasing the mechanical frictional force by performing the mechanical operation to the fully open position and the fully closed position during normal control. And a motor position control device. 17. An electronic circuit for controlling a motor, an interface circuit for connecting the electronic circuit to the outside, a turbocharger having variable vanes on an intake air introduction path for supplying intake air to an engine, and a motor rotation for an output shaft. In a motor position control device having a position detection device and having a motor for changing the direction of the variable blades of the turbocharger via a gear under the control of the electronic circuit, a fully open position or a full position within a control operation range of the motor A method for controlling a motor position of a turbocharger, wherein at least one of operations to a closed position is performed to set a reference point of a motor control position. 18. The method for controlling a motor position of a turbocharger according to claim 17, wherein the operation to the fully open position or the fully closed position is performed before starting the engine to which the motor position control device is attached. 19. The motor position control for a turbocharger according to claim 17, wherein the operation to the fully open position or the fully closed position is performed at least once each time the motor position control device is powered on. Method.