JP2003148157A - Device for controlling motor position of turbocharger, and method for controlling motor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve accuracy for detecting the position of a motor in 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, so as to equalize two kinds of signals. By the motor position control device, the motor position is once moved to an entire closed position or an entire opening position from an initial position, and an action in an entire opening or closed direction, which is opposed to the entire closed position or the entire opening position is performed after the motor is stopped. The movement volume between the entire opening position and the entire closed position is detected by the difference of the motor position signals at the time of the entire opening position and the motor position signals at the time of the entire closed position, so as to grasp the current position of the motor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor position control device for a turbocharger and a motor device control method.

[0002]

2. Description of the Related Art There is a method of measuring the absolute position of a motor by directly connecting a potentiometer whose resistance value changes in accordance with the rotation angle of the motor to the position of the motor when controlling the position of the motor, to the output shaft of the motor. In this case, the absolute position of the motor can be detected relatively easily, but if the potentiometer is a contact type, it is not durable and it is common to use a non-contact type potentiometer to prevent this. However, this potentiometer is expensive, and the output linearity with respect to the rotation angle may be poor, which may require correction.

As a countermeasure for this, there is a case where an incremental encoder having good linearity is used instead of the potentiometer.

However, when the incremental encoder is used, the absolute position cannot be detected.
The method is to detect the current position by performing processing such as turning the actuator all the way in one direction within the operating range at the start of operation, etc., determining the reference position in at least one direction, and then counting the number of encoder pulses. Was there.

A rotary encoder device is described in Japanese Patent No. 3039512.

[0006]

As described above, in the method of performing the alignment in only one direction before the start of control, the resistance component increases due to the increase of mechanical friction in the operating range and the motor is caught at this place. If the motor cannot be operated from this position, the motor stops at this position and control is performed with this position as a reference, so the accurate position of the motor cannot be detected.

An object of the present invention is to improve the motor position detection accuracy of a position control device using a motor.

[0008]

In order to achieve the above object, the motor driver is controlled by a target opening signal which is composed of a CPU, its peripheral circuits and an external I / F circuit and which is input at least from the outside. A control device for rotating the intake air introduction path of the turbocharger of the automobile by the output of the rotation shaft of the motor to adjust the charging pressure of the turbocharger, and the motor rotation provided on the output shaft of the motor. In the motor position control device that controls the motor position so that the output signal of the position detection device and the target opening signal are compared to each other, the motor position is temporarily moved from the initial position to the fully closed position or the fully opened position. After stopping at the fully closed position or fully open position, the motor is operated in the opposite direction, fully open or fully closed, and the motor position signal at the fully closed position and the fully closed position Difference by the fully open position of the motor position signal - detecting the amount of movement between the fully closed position, to grasp the current position of the motor.

After the operation to the fully closed position, the operation to the fully open position is performed, and the pulses during this time are counted to determine whether or not the operation is normal. This makes it possible to detect the absolute position, and by repeating this operation during normal control, the motor control position detection accuracy can be ensured and durable deterioration can be determined.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the configuration of an embodiment. In the present 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 above-mentioned encoder.

The ΦA signal and the ΦB signal are out of phase with each other by 90 degrees. For example, by looking at the level of the ΦB signal when ΦA rises or falls, the direction of rotation of the motor can be known, and the number of signal pulses can be 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. The signal 5a for driving the motor 2 is output so that the motor 2 is driven according to the control target position signal 6a.
It is a system that controls the rotational position of the.

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

CPU 9 (Central Processing Unit), I
/ O8 (Input / Output), A / D14 (Analog to Digita
l Converter), RAM15 (Random Access Memor
y), a ROM 16 (Read Only Memory), a non-volatile memory 17, a motor driver 10, and a communication driver 13, and in the case of this embodiment, a target opening signal 11b and a motor rotation position signal 11a input to the I / O.
The control signal 9a is output to the motor driver 10 so that the values of 1 and 2 become equal.

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.

In this control device, it is unknown where the motor is located when the power is turned on, so that the motor is first operated in the fully closing direction.

On the fully closed side, the boost pressure of the turbo is increased and the engine output is increased. Therefore, even when the engine is rotating, the throttle is fully closed and the turbo blades are closed. This is especially done when the power is turned on, because it is difficult to close it except in the mode where the boost pressure is hard to rise.

The count value of the pulse signal from the encoder mounted on the shaft of the motor decreases with the above operation.

This state is shown in FIG. When the motor moves to the closing side and reaches the fully closed position, the pulse count value does not change and the motor is locked.

In this state, when the change pulse count value for a certain period of time does not change, this position is determined to be the fully closed position.

After detecting the fully closed position, the motor is reversed in the opening direction.

Along with this, the pulse count value increases, and after reaching the fully open position, the pulse count value does not increase. If this state continues for a certain period of time, it is determined to be the fully open position. After this operation, the difference between the pulse count values should be essentially equal to the dynamic range C between the fully closed position and the fully open position, and if they are not the same, it can be determined to be abnormal.

The abnormality referred to here is a mode in which the mechanical resistance does not move at an intermediate position between the fully open position and the fully closed position due to an increase in the operating resistance of the mechanical part due to the change with time of the turbocharger. Count value B-count value A <dynamic range This is the case of C.

On the contrary, when the ridges of the gears of the motor drive device are lost, etc., the rotation and the like occur, so that the relationship of count value B-count value A> dynamic range C is established.

As described above, the absolute position can be detected by using the potentiometer while using the incremental encoder, and the failure diagnosis of the motor position control device can be performed.

It is not necessary to simultaneously perform the operation to the fully closed position, the operation to the fully opened position, and the comparison with the dynamic range. The fully closed operation is limited only when the power is turned on, idling, and when the power is shut off, and the fully opened operation is not performed. It is possible to do it frequently as long as it does not affect the drivability.

If the power is turned off after the motor position is set to the fully closed position, the fully open position, or a specific position in the normal state, the start position at the next power-on is uniquely determined. It is possible to detect the current position without performing the operation to the closed position and the operation to the fully open position.

FIG. 5 shows the case where a mechanical friction is increased in the motor position control device and a catch occurs between the fully closed position and the fully open position. The count value is monitored for the absolute position where the catch occurs. Since it can be understood from the fact that the motor is once returned to the specific position from the place where the catch occurs, it can be returned with a momentum and the part of the catch can be passed through, preventing the occurrence of catch due to deterioration of the durability of the turbocharger. it can.

In FIG. 6, the normal control is temporarily stopped during the normal control,
The operation when there is a need to return to normal control during the execution of this control is shown. The normal control in this case is control that is performed corresponding to the accelerator opening and the engine speed.

After the operation to the fully closed position is started, the vehicle is moved to the destination of the normal control. However, if the motor is operated at the same motor speed as that of the normal control, the time required to move to the destination is extra. It will take time and control delay will occur.

In this embodiment, in order to prevent the control delay, the control speed is moved faster than the normal control speed so that the response delay is not generated.

In this embodiment, the control speed is increased to initialize (to operate between the fully closed position and the fully open position).
However, the initialization may be interrupted midway to return to the normal control.

[0037]

According to the present invention, the position detection accuracy of the motor of the position control device using the motor can be improved.

[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 shows an example of initialization processing.

FIG. 5 is a method of counting motor positions using an encoder.

FIG. 6 shows a normalizing process at normal time.

[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.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) F04D 29/46 F02B 37/12 301Q (72) Inventor Shoji Sasaki 2520 Takaba, Hitachi, Naka, Ibaraki Prefecture Company Hitachi, Ltd. Automotive Equipment Group (72) Inventor Hiroaki Saeki 2477 Takaba, Hitachinaka City, Ibaraki Prefecture Stock Company Hitachi Car Engineering (72) Inventor Masayuki Sugawa 2520, Takaba, Hitachinaka City, Ibaraki Hitachi Ltd. F-terms in automobile equipment group (reference) 3G005 EA15 FA23 GA04 GB15 GB25 GD08 JA05 JA31 3G071 AB06 BA01 BA11 CA09 FA07 GA06 JA01 JA03 JA04 3H021 BA06 DA04 DA11 3H034 AA02 BB01 BB06 CC03 DD07 DD26 EE09 EE15

Claims (14)

[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 the two match. In the position control device, move the motor position from the initial position to the fully closed position or fully open position, stop at the fully closed position or fully open position, and then operate in the reverse direction, fully open or fully closed. The current position of the motor can be grasped by detecting the amount of movement between the fully open position and the fully closed position based on the difference between the motor position signal and the motor position signal at the fully closed position. Motor position controller. 2. The motor position control device according to claim 1, wherein the movement amount between the fully closed position and the fully opened position is mechanically clarified, that is, the fully closed position and the fully opened position. A motor position control device that compares the differences and determines that some failure has occurred between the fully closed position and the fully open position when the difference between the two is greater than a certain value. 3. The motor position control device according to claim 1, when the power is cut off to stop the operation, the operation is stopped after stopping the motor at the fully closed position or the fully open position. Motor position control device. 4. The motor position control device according to claim 1, when it is determined that a problem such as catching has occurred due to an increase in mechanical friction between the fully closed position and the fully open position, the problem A motor position control device characterized by storing the generated position. 5. The motor position control device according to claim 1, wherein when the operation is stopped due to a catch or the like during the operation between the fully closed position and the fully open position, the motor position is returned to the original position at least once. Is operated, the motor is operated again in the direction in which there is a catch, and the part where the catch is generated is passed by the momentum of the motor to eliminate mechanical friction such as a catch occurring. Motor position control device. 6. The motor position control device according to claim 1, wherein the operation to the fully closed position or the fully open position for detecting the current position of the motor is at least after power-on.
A motor position control device, which is performed immediately before power-off, when the engine is idling, or when the above operation is permitted. 7. The motor position control device according to claim 1, wherein the fully closed position for detecting the current position of the motor during normal control or the operation to the fully open position is permitted, so that the fully closed position is obtained. If it becomes necessary to perform normal control after the motor is moved to the fully open position or to the fully open position, the above operation is performed by operating the motor earlier than when operating to the fully open position or fully closed position. The motor position control device is characterized in that the response time is not delayed as compared with the case where it is not. 8. 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 orientation of the variable vanes of the turbocharger via a gear under the control of the electronic circuit, the variable vanes within the control operation range of the motor A method for controlling a motor position of a turbocharger, which comprises operating a fully open position and a fully closed position to set a reference point of a motor control position. 9. The operation according to claim 8, wherein the operation to the fully open position and the fully closed position is performed before the engine to which the motor position control device is attached is started and when the engine is powered off. A method of controlling a motor position of a turbocharger, which is performed at least one of immediately before the cutoff. 10. The motor position control for a turbocharger according to claim 8 or 9, wherein the operation to the fully open position and the fully closed position is performed at least once each time the motor position control device is powered on. Method. 11. The motor position control method according to claim 8 or 9, wherein after the variable vanes are moved to either the fully open position or the fully closed position, the power of the motor is shut off. 12. The method according to claim 8 or 9, wherein when the variable blade is moved from one of the fully open position and the fully closed position to the other, the load on the motor reaches a certain value or more, A motor position control method characterized in that the motor rotational position at which the load is generated is stored in the electronic circuit. 13. The moving blade according to claim 8, wherein one of the fully open position and the fully closed position is a starting point and the other is an ending point, and the variable blade is moved from the starting point to the ending point. In addition, when the load on the motor reaches a certain value or more, the variable vane is returned to a direction approaching the starting point and moved again toward the ending point. 14. The motor according to claim 8 or 9, wherein when the electronic circuit receives a signal for performing a normal operation during the operation to the fully open position and the fully closed position, the operation speed of the motor is increased. And motor position control method.