JP2007288948A - Motor controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress the deterioration of the control accuracy of a motor operation position caused by a shift of a detection operation position from an actual operation position, and suppress the erroneous determination of a defective operation status. <P>SOLUTION: This device is provided with a stopper member for restricting changes in a ratio angle of a brushless motor at a limit operation angle; and a position detecting system for detecting the rotation angle of the motor (detected rotation angle) on the basis of an output signal of a position sensor cyclically changing in response to a change in rotation angle. The device executes feedback control based on the detected rotation angle, and abnormality determination for determining that the device is in an operation defective state in a state that the detected rotation angle does not match a target rotation angle. If it is determined that the detected rotation angle does not match an actual rotation angle (NO in S219), the detected rotation angle is corrected to match the angles (S211-S218), and the execution of abnormality determination is prohibited (S221) until the detected rotation angle matches the actual rotation angle (NO→YES in S219). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a motor control device that controls driving of a motor based on an actual operation position of the motor.

  In recent years, for example, a motor (for example, an electric rotating machine) is frequently used as a drive source for driving various mechanisms such as a variable valve mechanism for changing valve characteristics of an engine valve of an internal combustion engine. Such a motor control device that controls the operation position of the motor includes a position detection system that includes a position sensor that outputs a signal corresponding to the operation position of the motor, an electronic control device that captures the output signal, and the like. Then, the operation position of the motor is feedback-controlled so that the operation position detected by the position detection system matches the operation position corresponding to the target drive state of various mechanisms (see Patent Document 1).

  Further, as a position sensor, a motor control device provided with a sensor that periodically changes an output signal with a change in the operation position of the motor, such as an encoder, is often used. In this motor control device, the operation position stored in the electronic control device (specifically, its memory) is sequentially updated in accordance with the periodic change in the output signal of the position sensor, and the updated operation position is It is detected as an operating position.

  On the other hand, the motor control device is in a malfunction state in which the motor operation position cannot be changed properly, for example, the motor cannot be rotated due to the foreign matter biting into various mechanisms or the motor itself. May be. In order to appropriately cope with such a malfunction state, an apparatus for determining the occurrence of an abnormality has been put into practical use.

Incidentally, the operation failure state can be determined when, for example, all the conditions described below are satisfied.
-The operation position of the motor is not a position (limit operation position) that is regulated by the contact between the stopper member and the portion that operates as the motor is driven.
• The motor is driven to change the motor operating position.
• The motor operating position has not changed.
JP 2005-23883 A

  By the way, in the motor control device, noise enters the output signal of the position sensor, or a phenomenon in which power supply to the position detection system is stopped for a very short time (so-called instantaneous interruption phenomenon) occurs. As a result, the operation position (detection operation position) detected by the position detection system may deviate from the actual operation position (actual operation position).

  In this case, it becomes impossible to drive the motor, and thus various mechanisms, in a target driving state. Further, if the actual operation position may become the limit operation position in this state, it is determined that the detection operation position is not the limit operation position but the motor can be rotated at this time. Nevertheless, there is a possibility that the motor cannot actually be rotated in a specific direction, so that it may be erroneously determined as the above-described malfunction state.

  Here, when the detected operation position deviates from the actual operation position as described above, it is also conceivable to execute a correction process for matching the detected operation position and the actual operation position. By executing such a correction process, the deviation between the detected operation position and the actual operation position is eliminated, and a decrease in the control accuracy of the motor operation position is suppressed.

  However, even in such a device, if the actual operation position becomes the limit operation position before the deviation between the detection operation position and the actual operation position is resolved, the operation is There is a risk of erroneous determination.

  Although the apparatus that performs the correction process as described above can suppress a decrease in the control accuracy of the motor operation position, it cannot be said that it is possible to accurately avoid an erroneous determination of an operation failure state. There remains room for improvement.

  The present invention has been made in view of such circumstances, and an object of the present invention is to suppress a decrease in control accuracy of the motor operation position due to the detection operation position deviating from the actual operation position and to erroneously determine an operation failure state. It is an object of the present invention to provide a motor control device capable of accurately suppressing the above.

In the following, means for achieving the above object and its operational effects will be described.
According to a first aspect of the present invention, there is provided a stopper member that restricts a change in the operation position of the motor at a limit operation position through contact with a portion that operates as the motor is driven, and a change in the operation position of the motor. And a position detection system that detects the operation position of the motor based on the output signal of the position sensor that periodically changes, and the detection operation position detected by the position detection system becomes a target operation position. In addition, the feedback control of the operation position of the motor based on the detected operation position is executed, and when the detected operation position does not change in a situation where the detected operation position and the target operation position do not match, A motor control device that executes an abnormality determination to determine that there is a match, the presence or absence of a match between the detected operation position and the actual operation position. When it is determined that the detected operation position is corrected, the abnormality determination is performed until the detected operation position and the actual operation position match through the correction. The gist is to prohibit it.

  According to the above configuration, when the detected operation position does not match the actual operation position, the mismatch is eliminated through correction of the detected operation position. Therefore, it is possible to suppress a decrease in control accuracy of the motor operation position due to the detection operation position deviating from the actual operation position.

  Here, if the actual operation position becomes the limit operation position when the actual operation position does not match the detection operation position, the detection operation position is not the limit operation position but the position where the motor can be rotated. However, the motor cannot be rotated in a specific direction. Therefore, if the abnormality determination is executed at this time, it is erroneously determined that the operation is in a malfunctioning state. In this regard, according to the above-described configuration, when the detected operation position and the actual operation position do not coincide with each other, execution of abnormality determination is prohibited, so that erroneous determination of an operation failure state can be accurately suppressed. Can do.

  According to a second aspect of the present invention, in the motor control device according to the first aspect, the motor is an electric rotating machine, and a plurality of pulse signals whose phases are shifted from each other with the rotation thereof are periodically output. The electrical angle sensor is driven through switching of energized phases based on the output pattern of the electrical angle sensor, and the position detection system outputs pulse signals that are out of phase with each other as the motor rotates. A plurality of the position sensors that output each of them, and an edge interval of pulse signals from the position sensors is set shorter than an edge interval of pulse signals from the plurality of electrical angle sensors, The operation position of the motor is detected based on the count value obtained by counting the edges of the pulse signal from the position sensor. Every time an edge of a pulse signal from a plurality of electrical angle sensors is generated, an actual relationship between the count value at the time of the previous edge generation and the count value at the time of the current edge generation is obtained, and the obtained actual relationship is a normal relationship. The gist is to be judged with different things.

  Usually, when a motor (electric rotating machine) rotates, pulse signals whose phases are shifted from each other are periodically output from a plurality of electrical angle sensors. Therefore, by counting the edges of the pulse signals from these electric angle sensors, it is possible to roughly detect the operation position (rotation angle) of the motor based on the count value. However, when high accuracy is required for detecting the operation position of the motor, such rough position detection is insufficient in detection accuracy. Therefore, in the above configuration, a position sensor that periodically outputs a pulse signal at an edge interval shorter than the edge interval of the pulse signal from each electrical angle sensor as the motor rotates is provided, and the pulse signal from the position sensor is The operating position of the motor is detected based on the count value obtained by counting the edges. This makes it possible to detect the operation position of the motor with high accuracy.

  In such a device, when noise enters the signal from the position sensor, the edge of the noise is mistakenly recognized as the edge of the pulse signal from the position sensor, and this is counted, and the count value does not correspond to the actual operating position of the motor. There is a risk of becoming.

  In the above configuration, the deviation of the count value from the value corresponding to the actual operation position is the difference between the count value at the previous edge generation of the pulse signal from each electrical angle sensor and the current edge generation. Appears in relation to the count value. Specifically, the actual relationship deviates from the normal relationship by the deviation.

  According to the above configuration, it is determined that the detected motion position and the actual motion position match when the actual relationship and the normal relationship are the same, and the actual relationship and the normal relationship are different from each other. The presence / absence of a match between the detected motion position and the actual motion position can be determined using the actual relationship, such as determining that the motion positions do not match. Moreover, the actual relationship can be obtained by using an electrical angle sensor that is usually attached to the motor for driving without adding a new sensor or the like for obtaining this.

The actual relationship includes the difference between the count value at the time of the previous edge generation of the pulse signal from each electrical angle sensor and the count value at the time of the current edge generation, and the ratio of the count values.
According to a third aspect of the present invention, in the motor control device according to the second aspect, the correction of the detection operation position is equivalent to the amount of deviation of the actual relationship from the normal relationship. It is the gist of what is done by changing.

  According to the above configuration, the deviation of the count value from the value corresponding to the actual operation position can be accurately corrected, and the deviation of the detection operation position from the actual operation position can be accurately corrected.

  The gist of the invention described in claim 4 is that, in the motor control device according to claim 3, the count value is gradually changed so that the detection operation position gradually shifts to the actual operation position. And

  Here, when the detection operation position is corrected, it is gradually changed, so that it is possible to avoid a sudden change in the motor rotation torque accompanying the correction. However, in this case, since the period until the detected operation position coincides with the actual operation position becomes longer, there is a high possibility that the operation failure state described above is erroneously determined.

According to the said structure, in the apparatus which changes a detection operation position gradually in that way, the misjudgment of a malfunctioning state can be suppressed appropriately.
According to a fifth aspect of the present invention, in the motor control device according to any one of the first to fourth aspects, the motor is used to drive a variable valve mechanism that changes a valve characteristic of an engine valve of an internal combustion engine. The gist of this is

  When the motor is used to drive a variable valve mechanism of an internal combustion engine, the operation position of the motor is detected by a position detection system, and the detected operation position becomes a position corresponding to a target valve characteristic. The motor is driven as follows. As a result, the variable valve mechanism is driven and controlled so that the valve characteristic of the engine valve becomes the target valve characteristic. According to the said structure, while being able to suppress the fall of the control precision of such a variable valve mechanism, the misdetection about the malfunctioning state can be suppressed exactly.

Hereinafter, an embodiment in which a motor control device according to the present invention is embodied will be described.
FIG. 1 shows a cross-sectional structure around a cylinder head of an internal combustion engine on which a motor control device according to the present embodiment is mounted.

  As shown in FIG. 1, a combustion chamber 6 is defined by a cylinder head 2, a cylinder block 3, and a piston 5 inside the internal combustion engine 1, and an intake passage 7 and an exhaust passage 8 are formed in the combustion chamber 6. Is connected. The combustion chamber 6 and the intake passage 7 are connected and cut off by the opening / closing operation of the intake valve 9, and the combustion chamber 6 and the exhaust passage 8 are connected and cut off by the opening / closing operation of the exhaust valve 10.

  The cylinder head 2 is provided with an intake camshaft 11 for driving the intake valve 9 and an exhaust camshaft 12 for driving the exhaust valve 10. The intake camshaft 11 and the exhaust camshaft 12 rotate by transmission of rotation from the crankshaft of the internal combustion engine 1. The intake camshaft 11 is provided with an intake cam 11a, and the exhaust camshaft 12 is provided with an exhaust cam 12a. Then, the intake valve 9 is opened and closed through integral rotation of the intake camshaft 11 and the intake cam 11a, and the exhaust valve 10 is opened and closed through integral rotation of the exhaust camshaft 12 and the exhaust cam 12a.

  In addition, a variable valve mechanism that varies the valve characteristics of the intake valve 9 (specifically, the maximum lift amount of the intake valve 9 and the operating angle of the intake cam 11a) between the intake valve 9 and the intake cam 11a. 14 is provided. The drive control of the variable valve mechanism 14 is executed so that, for example, the maximum lift amount and the operating angle increase as the engine operation state that requires a larger amount of intake air is achieved. This is because as the maximum lift amount of the intake valve 9 and the operating angle of the intake cam 11a are increased, the intake of air from the intake passage 7 to the combustion chamber 6 is performed more efficiently, and the above-described requirements regarding the intake air amount can be satisfied. This is possible.

Next, the structure of the variable valve mechanism 14 will be described.
The variable valve mechanism 14 includes a rocker shaft 15 and a control shaft 16 that extend parallel to the intake camshaft 11, and an input arm 17 and an output arm 18 that swing about the axes of the shafts 15 and 16. Yes. When the input arm 17 swings when pushed by the rotating intake cam 11a, the output arm 18 swings accordingly.

  The input arm 17 is urged toward the intake cam 11a by a spring 20 so as to be pressed against the intake cam 11a. A rocker arm 21 is provided between the output arm 18 and the intake valve 9, a base end portion of the rocker arm 21 is supported by a lash adjuster 22, and a distal end portion is in contact with the intake valve 9. Further, the rocker arm 21 is urged toward the output arm 18 by the valve spring 24 of the intake valve 9 and is pressed against the output arm 18. When the input arm 17 swings together with the output arm 18 as the intake cam 11a rotates, the swing of the output arm 18 is transmitted to the intake valve 9 via the rocker arm 21, and the intake valve 9 is lifted. The

  In the variable valve mechanism 14, the rocker shaft 15 is formed in a pipe shape, and the control shaft 16 is disposed in the rocker shaft 15 so as to be movable in the axial direction. The variable valve mechanism 14 has a structure capable of changing the relative position of the input arm 17 and the output arm 18 in the swinging direction by changing the axial position of the control shaft 16 with respect to the rocker shaft 15. By changing the relative position of the input arm 17 and the output arm 18 in the swing direction in this way, the maximum lift of the intake valve 9 when the output arm 18 swings with the rotation of the intake cam 11a. The amount and the operating angle of the intake cam 11a with respect to the intake valve 9 are changed. Specifically, the closer the input arm 17 and the output arm 18 are to each other in the swing direction, the smaller the maximum lift amount of the intake valve 9 and the operating angle of the intake cam 11a.

  Next, a drive mechanism for displacing the control shaft 16 in the axial direction to drive the variable valve mechanism 14 and a control device for controlling the drive of the drive mechanism will be described with reference to FIG.

  As shown in FIG. 2, a brushless motor 25 is connected to a base end portion (right end portion in the drawing) of the control shaft 16 via a conversion mechanism 26. The conversion mechanism 26 is for converting the rotational motion of the brushless motor 25 into linear motion in the axial direction of the control shaft 16. The control shaft 16 is displaced in the axial direction through rotational driving within a predetermined rotation angle range (for example, a rotation angle range for 10 rotations (0 to 3600 °)) of the brushless motor 25, and a variable valve mechanism. 14 is driven.

  The variable valve mechanism 14 contacts the control shaft 16 and a stopper member 27 that restricts the movement of the control shaft 16 toward the tip (left end in the figure) at the limit operation position, and the base of the control shaft 16. A stopper member 28 that restricts movement toward the end (right end in the figure) at the limit operation position is provided. Regarding the rotation angle of the brushless motor 25, the angle corresponding to the limit operation position on the distal end side of the control shaft 16 and the angle corresponding to the limit operation position on the base end side are the limit operation positions (limit operation angles). The predetermined rotation angle range is determined by the limit rotation angle.

  Incidentally, when the brushless motor 25 is rotated in the forward direction, the control shaft 16 is displaced to the tip side, and the relative positions of the input arm 17 and the output arm 18 in the swing direction are changed so as to approach each other. On the other hand, when the brushless motor 25 is rotated in the reverse direction, the control shaft 16 is displaced to the proximal end side, and the relative positions of the input arm 17 and the output arm 18 in the swing direction are changed so as to be separated from each other.

  The brushless motor 25 is a 4-pole 6-winding motor having three-phase windings. The brushless motor 25 is driven through switching of a phase for supplying power (an energized phase). Specifically, six energization patterns that can be switched are set in the brushless motor 25, and when the drive of the brushless motor 25 is controlled, one of these energization patterns is selectively set. Energization of the windings of each phase of the brushless motor 25 is performed.

  The apparatus according to the present embodiment includes an electronic control unit 30 that executes various engine controls such as drive control of the brushless motor 25. The electronic control unit 30 includes a CPU that executes various arithmetic processes, a ROM that stores programs and data necessary for the arithmetic operation, a RAM such as a nonvolatile memory 30a that temporarily stores the arithmetic results of the CPU, an external Input / output ports for inputting / outputting signals to / from.

  Three electrical angle sensors S1, S2, S3 and two position sensors S4, S5 are connected to the input port of the electronic control unit 30. In the present embodiment, the electric angle sensors S1 to S3 and the electronic control device 30 constitute a position detection system that detects the operating position (rotation angle) of the brushless motor 25. An input port of the electronic control unit 30 has an accelerator position sensor 31 for detecting the amount of depression of the accelerator pedal, a rotation speed sensor 32 for detecting the rotation speed of the crankshaft of the internal combustion engine 1 (engine rotation speed), An ignition switch 33 and the like are also connected.

A drive circuit for the brushless motor 25 is connected to the output port of the electronic control unit 30.
In controlling the driving of the brushless motor 25, the electronic control unit 30 calculates the engine operating state and the rotation angle of the brushless motor 25 based on the output signals of various sensors, and the brushless motor 25 is operated based on the calculation result. Driven. As a result, the drive of the variable valve mechanism 14 (specifically, the axial position of the control shaft 16) is controlled, and the valve characteristics of the intake valve 9 are controlled.

  Incidentally, the valve characteristic of the intake valve 9 corresponds to the axial position of the control shaft 16, in other words, the rotation angle of the brushless motor 25 within the predetermined rotation angle range. Therefore, in order to accurately control the valve characteristics of the intake valve 9, the rotation angle of the brushless motor 25 is accurately detected, and the brushless motor 25 is adjusted so that the rotation angle becomes an angle corresponding to the target valve characteristic. It becomes important to drive.

  Therefore, in this embodiment, the rotation angle of the brushless motor 25 is detected based on the output signals of the electrical angle sensors S1 to S3 and the position sensors S4 and S5 described above, and the rotation angle is highly accurate. Is detected.

Hereinafter, a procedure for detecting the rotation angle of the brushless motor 25 will be described.
Here, first, output signals of the sensors S1 to S5 will be described.
FIG. 3 shows changes in the output signals of the sensors S1 to S5 accompanying the change in the rotation angle of the brushless motor 25 ((a) to (e) in FIG. 3), and various counters that are changed according to the changes in the output signals (F) to (h) in FIG.

  As shown in FIG. 3, each of the electrical angle sensors S <b> 1 to S <b> 3 ((a) to (c) in FIG. 3) has four poles that rotate integrally with the rotor of the brushless motor 25 when the brushless motor 25 rotates. A pulse signal, that is, a high signal “H” and a low signal “L” are alternately and periodically output according to the magnetism of the multipolar magnet. The circumferential positions of the electrical angle sensors S1 to S3 with respect to the rotor are determined so that the pulse signals from the electrical angle sensors S1 to S3 are output at a timing shifted from each other. Note that the edges of the pulse signals output from the electrical angle sensors S1 to S3 are generated every 45 ° rotation of the brushless motor 25, respectively. Further, the pulse signal from one of the electrical angle sensors S1 to S3 is delayed or delayed by 30 ° of the brushless motor 25 with respect to the pulse signals from the other two sensors. Occurs at the rotation angle.

  On the other hand, each of the position sensors S4 and S5 (FIGS. (D) and (e)) corresponds to the magnetism of the 48-pole multipole magnet that rotates integrally with the rotor of the brushless motor 25 when the brushless motor 25 rotates. Thus, a pulse signal, that is, a high signal “H” and a low signal “L” are alternately and periodically output. The circumferential positions of the position sensors S4 and S5 with respect to the rotor are determined so that the pulse signals from the position sensors S4 and S5 are output at a timing shifted from each other. The edges of the pulse signals output from the position sensors S4 and S5 are generated every 7.5 ° rotation of the brushless motor 25, respectively. Further, the pulse signal from one of the position sensors S4 and S5 is generated at a rotation angle shifted by 3.75 ° rotation of the brushless motor 25 with respect to the pulse signal from the other sensor.

  Thus, the edge interval of the pulse signals from the position sensors S4 and S5 is shorter (3.75 °) than the edge interval (15 °) of the pulse signals from the electrical angle sensors S1 to S3. Further, every time the edge of the pulse signal from the position sensors S4 and S5 is generated four times, the edge of the pulse signal from the electric angle sensors S1 to S3 is generated once.

Next, the count values of various counters that are changed according to the output signals of the sensors S1 to S5 will be described with reference to FIGS.
FIG. 4 is a flowchart showing a specific processing procedure of processing (count processing) for changing count values of various counters. A series of processing shown in this flowchart is periodically executed by the electronic control unit 30 at intervals shorter than the edge intervals of the pulse signals from the position sensors S4 and S5.

  As shown in FIG. 4, in this process, first, in the process of step S101, the electrical angle counter is based on the output patterns of the pulse signals (FIGS. 3A to 3C) from the electrical angle sensors S1 to S3. Count value Ce (FIG. 3F) is changed. Specifically, as shown in FIG. 5A, the relationship between the count value Ce of the electrical angle counter and the above output pattern, the output value (high signal) of each electrical angle sensor S1 to S3 is used as the count value Ce of the electrical angle counter. Depending on the combination of “H” or low signal “L”), any one of the integer values “0” to “5” is set. Specifically, when the brushless motor 25 rotates in the forward direction, every time it rotates 15 °, “0” → “1” → “2” → “3” → “4” → “5” → “0” A value that changes in order is set as the count value Ce of the electrical angle counter.

  Each value (0, 1, 2, 3, 4, 5) set as the count value Ce corresponds to each of the six energization patterns of the brushless motor 25 described above. In the present embodiment, the rotation of the brushless motor 25 is controlled by switching the energization pattern for the windings of each phase of the brushless motor 25 based on the count value Ce of the electrical angle counter.

  Next, in the processing of step S102 (FIG. 4), the count value Cp (FIG. 3 (FIG. 3)) of the position counter is based on the output pattern of the pulse signal from each position sensor S4, S5 (FIG. 3 (d), (e)). g)) is increased or decreased. The count value Cp of the position counter is increased or decreased at the timing when the output signal of one of the position sensors S4 and S5 becomes a rising edge or a falling edge. Specifically, as shown in FIG. 5B, the relationship between the count value Cp of the position counter and the above output pattern, the output signal of one of the position sensors S4 and S5 is a rising edge “↑” or a falling edge “ ↓ "and the count value Cp of the position counter is" +1 "or"-"depending on whether the output signal of the other sensor is the high signal" H "or the low signal" L ". 1 "is added.

  Through such processing, the count value Cp of the position counter is incremented by “1” at the time of forward rotation of the brushless motor 25 and “1” at the time of reverse rotation every time the pulse signal from each of the position sensors S4 and S5 becomes an edge. Subtracted one by one. The count value Cp of the position counter is reset to “0” every time the ignition switch 33 is turned off. Therefore, the count value Cp of the position counter is a value corresponding to the amount of change in the rotation angle of the brushless motor 25 after the ignition switch 33 is turned on.

  Thereafter, in the process of step S103 (FIG. 4), the count value Cs (FIG. 3 (h)) of the stroke counter is changed in accordance with the count value Cp of the position counter that changes as described above. Specifically, a value (= Cp−Pr) obtained by adding a value (−Pr) obtained by inverting the sign of a learning value Pr, which will be described later, to the count value Cp of the position counter is set as the count value Cs of the stroke counter.

  Note that the learning value Pr is the value of the position counter when the rotation angle of the brushless motor 25 is changed so that the control shaft 16 is in the limit operation position on the tip end side (left end side in FIG. 2) in the movable range. This is a value corresponding to the count value Cp. The learning value Pr is learned when a predetermined learning condition is satisfied after the ignition switch 33 is turned on, and is stored in the nonvolatile memory 30a of the electronic control unit 30. Therefore, the count value Cs of the stroke counter obtained as described above is a value representing the rotation angle of the brushless motor 25 with the angle corresponding to the limit operation position of the control shaft 16 as a reference.

  In the present embodiment, the count value Ce of the electrical angle counter and the count value Cs of the stroke counter thus obtained are used as the rotation angle of the brushless motor 25, and the brushless motor 25 based on the rotation angle is used. Drive control is executed.

  Hereinafter, the process concerning the drive control of the brushless motor 25 will be specifically described. Note that a series of processing relating to this drive control is executed by the electronic control device 30 at predetermined intervals shorter than the edge generation cycle of the pulse signals from the position sensors S4 and S5.

First, of the above drive control, control for adjusting the rotational torque of the brushless motor 25 based on the count value Cs of the stroke counter will be described.
In the process related to this control, first, a control target value (target rotation angle TMA) for the rotation angle of the brushless motor 25 is calculated based on the depression amount of the accelerator pedal and the engine rotation speed. Next, a deviation between the target rotation angle TMA and the rotation angle detected as described above (detected rotation angle MA (here, count value Cs of the stroke counter)) is obtained, and motor control is performed based on the deviation. The quantity Msig is calculated. And according to this motor control amount Msig, the power supply amount and power supply time with respect to the winding of each phase of the brushless motor 25 are adjusted. Through such processing, the rotational torque of the brushless motor 25 is adjusted to match the engine operating state. When the target rotation angle TMA and the detected rotation angle MA coincide with each other, the rotation angle of the brushless motor 25 is maintained at the current angle with respect to each winding corresponding to the energization pattern set at this time. A predetermined amount of power that can be supplied is supplied.

  Incidentally, the amount of electric power supplied to the brushless motor 25 is adjusted by setting a duty signal output to the drive circuit of the brushless motor 25 according to the motor control amount Msig. This duty signal is a signal that defines a ratio (duty ratio) between a time during which power is supplied to the brushless motor 25 and a time during which the same power is not supplied in a very short predetermined unit time. The higher the power is, the more electric power is supplied to the brushless motor 25.

Next, control for switching the energized phase of the brushless motor 25 based on the count value Ce of the electrical angle counter in the drive control will be described.
When the target rotational angle TMA and the detected rotational angle MA are different, the energization patterns described above are sequentially switched so that the brushless motor 25 rotates in the rotational direction determined by the relationship between the target rotational angle TMA and the detected rotational angle MA. It is done.

  Since the rotation speed of the brushless motor 25 is not constant, if the energization pattern is switched simply by changing the count value Ce of the electrical angle counter, the execution time of the processing for the switching and the rise time of the current in the winding As a result, a difference occurs in the timing when the energization pattern is actually switched. When such a deviation occurs, this causes an unnecessary decrease in the rotational torque of the brushless motor 25, and the variable valve mechanism 14 cannot be driven appropriately.

  The higher the rotational speed of the brushless motor 25, the shorter the time interval at which the count value Ce changes. On the other hand, the rotational speed of the brushless motor 25 changes depending on the execution time of the processing for switching, the rise time of the current in the winding, and the like. It doesn't change much. Therefore, by starting the switching of the energization pattern at an earlier timing as the rotational speed of the brushless motor 25 is higher, it is possible to match the timing at which the count value Ce changes with the timing at which the energization pattern is actually switched. It can be said. Based on this point, in the present embodiment, on the basis of the timing at which the count value Ce of the electrical angle counter changes, the switching of the energization pattern is started at an earlier time as the rotational speed of the brushless motor 25 is higher. An energization pattern (target energization pattern) as a control target is set.

  When the target energization pattern is set in this way, the amount of change in the count value Cp of the position counter and the amount of change in the count value Cs of the stroke counter during a predetermined period are used as the rotation speed of the brushless motor 25. .

  As described above, by executing the drive control of the brushless motor 25 based on the count value Cs of the stroke counter and the count value Ce of the electric angle sensor, the detected rotation angle MA is accurately controlled to the target rotation angle TMA. As a result, the valve characteristic of the intake valve 9 is accurately controlled to the target characteristic.

  The motor control device according to the present embodiment is in an operation failure state (motor lock state) in which the rotation angle of the brushless motor 25 cannot be changed due to foreign matter biting into the variable valve mechanism 14 or the brushless motor 25. May be. For this reason, in the present embodiment, an abnormality determination for determining whether or not a motor lock state has occurred is executed.

In this abnormality determination, it is determined that the motor is locked when the detected rotation angle MA does not change in a situation where the target rotation angle TMA and the detected rotation angle MA do not match. Specifically, the occurrence of abnormality is determined when all of the following (Condition 1) to (Condition 3) are satisfied.
(Condition 1) The control shaft 16 is not in contact with the stopper members 27 and 28. Specifically, the detected rotation angle MA is not the limit operating angle.
(Condition 2) A current is actually flowing through the brushless motor 25. Specifically, the winding current of the brushless motor 25 is a predetermined amount or more. The winding current is detected using, for example, a current detection resistor incorporated in a switching element that switches between energization / non-energization of each phase winding of the brushless motor 25.
(Condition 3) The target rotation angle TMA and the detected rotation angle MA are different, and the brushless motor 25 is driven to change the detected rotation angle MA. Specifically, the duty ratio of the duty signal is not less than a predetermined ratio.

  By the way, the count value Cp of the position counter does not always correspond to the actual rotation angle of the brushless motor 25, and may deviate from the value corresponding to the actual rotation angle. For example, when noise is generated in the signals output from the position sensors S4 and S5, the edge due to the noise cannot be distinguished from the edge of the pulse signal from the position sensors S4 and S5, and the edge due to the noise is regarded as the edge of the pulse signal. This is mistakenly counted, and the count value Cp of the position counter does not correspond to the actual rotation angle of the brushless motor 25.

  Hereinafter, a situation where such a problem occurs will be described in detail with reference to FIG. In FIG. 6, (a) and (b) show changes in the output signals of the position sensors S4 and S5, (c) shows changes in the count value Ce of the electrical angle counter, and (d) shows the brushless motor 25. (E) shows the transition of the count value Cp of the position counter during the reverse rotation.

  During the forward rotation of the brushless motor 25, when noise enters the signal from the position sensor S4 ((a) in the figure) and the noise overlaps with the falling edge of the pulse signal from the position sensor S5, the above noise is generated. The output pattern of signals from the position sensors S4 and S5 at the timings T12, T13, and T14 is as shown in FIG. As a result, at timings T12, T13, and T14, “−1” is added to the count value Cp of the position counter, and the count value Cp decreases by “1” as shown by a two-dot chain line in FIG. Go.

  If the noise does not enter here, as indicated by a solid line in FIG. 6D, the count value Cp of the position counter is not changed at timings T12 and T14, and the count value Cp of the position counter is changed to timing T13. “1” is added.

  For this reason, when the noise enters, the count value Cp of the position counter (two-point difference line) is “4” with respect to the value (solid line) corresponding to the actual rotation angle of the brushless motor 25 after the timing T14. Only smaller.

  On the other hand, when the brushless motor 25 rotates in the reverse direction, noise enters the signal from the position sensor S4 (FIG. 5A) and overlaps the rising edge of the pulse signal from the position sensor S5. The count value Cp of the position counter deviates from a value corresponding to the actual rotation angle of the brushless motor 25.

  That is, the output patterns of signals from the position sensors S4, S5 at the timings T14, T13, T12 where the noise is generated become patterns as shown in FIG. 7B, and at the timings T14, T13, T12, respectively. “1” is added to the count value Cp of the position counter. As a result, as indicated by a two-dot difference line in FIG. 6E, the count value Cp increases by “1” at timings T14, T13, and T12.

  If the noise does not enter, the count value Cp of the position counter is not changed at timings T14 and T12, and “−1” is added to the count value Cp at timing T13.

  For this reason, when the noise occurs, the count value Cp of the position counter (two-point difference line) is “4” with respect to the value (solid line) corresponding to the actual rotation angle of the brushless motor 25 after timing T12. Only get bigger.

  Thus, when the count value Cp of the position counter does not correspond to the actual rotation angle of the brushless motor 25, the detection of the brushless motor 25 detected based on the count value Cp (more precisely, the count value Cs of the stroke counter). The rotation angle MA becomes an incorrect value. Therefore, even if the drive control of the brushless motor 25 is executed based on the detected rotation angle MA, the variable valve mechanism 14 cannot be driven in the target drive state, and the valve characteristic of the intake valve 9 is the target. There is a risk that the operation of the internal combustion engine 1 will be adversely affected.

  In order to suppress the occurrence of such inconvenience, a deviation amount between the count value of the position counter corresponding to the actual rotation angle of the brushless motor 25 and the count value Cp of the actual position counter is obtained, and the amount corresponding to the deviation amount is obtained. It is only necessary to correct the count value Cp. In the present embodiment, the following processing (a) to (d) is executed to correct the count value Cp of the position counter, and the count value Cp corresponds to the actual rotation angle of the brushless motor 25. To return to the value you want.

  (A) Every time the edge of the pulse signal from the electrical angle sensors S1 to S3 is generated, the difference ΔCp (= the difference between the count value Cpt of the position counter when the current edge is generated and the count value Cpl of the position counter when the previous edge is generated) Cpt−Cpl) is calculated.

  (B) Based on the change in the count value Ce of the electrical angle counter, it is determined whether the rotation state of the brushless motor 25 is “forward rotation state”, “reverse rotation state”, or “rotation inversion state”. Specifically, first, the change direction of the count value Ce when the current edge occurs and the change direction of the count value Ce when the previous edge occurs are obtained. As shown in FIG. 8, when both of the change directions are directions indicating the normal rotation of the brushless motor 25, it is determined that the rotation direction is normal, and both the change directions indicate a reverse rotation of the brushless motor 25. If it is, it is determined that the vehicle is in the reverse rotation state. When the change directions are different from each other, it is determined that the rotation is reversed.

  (C) A normal value J that is a normal value of ΔCp is set according to the rotation state of the brushless motor 25. Specifically, “n” is set as the normal value J in the case of the forward rotation state, “−n” is set in the case of the reverse rotation state, and “−n” is set in the case of the rotation inversion state. “0” is set. Note that “n” is the number of edges of the pulse signals output from the position sensors S4 and S5 between the edges of the pulse signals from the electrical angle sensors S1 to S3 (“4” in the present embodiment).

(D) A deviation “J−ΔCp” of the difference ΔCp from the normal value J is calculated as a correction value Kcp, and a correction corresponding to the correction value Kcp is added to the count value Cp of the position counter.
In the apparatus of the present embodiment, when the count value Cp of the position counter deviates from a value corresponding to the actual rotation angle of the brushless motor 25 due to the occurrence of the noise, the difference ΔCp is equal to the normal value J by the deviation. The deviation appears in the difference ΔCp, such as deviating. Therefore, as in the process (d) above, the correction of the difference ΔCp by the correction value Kcp corresponding to the amount of deviation from the normal value J is added to the count value Cp of the position counter, so The deviation of the count value Cp from the value corresponding to the rotation angle can be eliminated. Further, in the present embodiment, the electrical angle sensors S1 to S3 attached to the brushless motor 25 are used for driving without adding a new sensor or the like for obtaining the difference ΔCp and the correction value Kcp. Can be obtained.

Hereinafter, an outline of correction of the count value Cp of the position counter described above will be described with reference to FIG.
As described above, when noise enters the output signal of the position sensor S4 (FIG. 4A) during the forward rotation of the brushless motor 25 (timing T12 to T14), the count value Cp of the position counter (FIG. 4D). (Value indicated by a two-dot difference line) is smaller by “4” than the value corresponding to the actual rotation angle of the brushless motor 25 (value indicated by the solid line in FIG. 4D). Thereafter, when the count value Ce (c) of the electrical angle counter changes (timing T11), the difference ΔCp is a value shifted by “−4” with respect to the normal value J (= 4). (= 0) is calculated. Then, the deviation amount (= 4) of the difference ΔCp from the normal value J is calculated as the correction value Kcp, and the correction value Kcp is added to the count value Cp (two-dot chain line) of the position counter. As a result, the count value Cp of the position counter is corrected so as to be a value (solid line) corresponding to the actual rotation angle of the brushless motor 25 as indicated by an arrow A in FIG.

  On the other hand, as described above, when noise enters the output signal of the position sensor S4 (FIG. 5A) during the reverse rotation of the brushless motor 25 (timing T14 to T12), the count value Cp of the position counter (FIG. (A value indicated by a two-dot difference line in (e)) is increased by “4” with respect to a value corresponding to the actual rotation angle of the brushless motor 25 (a value indicated by a solid line in (e) of FIG. 5). Thereafter, when the count value Ce (FIG. 6C) of the electric angle counter changes (timing T14), the value ΔCp is shifted by “4” from the normal value J (= −4) (= 0). ) Is calculated. Then, the deviation amount (= −4) of the difference ΔCp from the normal value J is calculated as the correction value Kcp, and the correction value Kcp is added to the count value Cp (two-dot chain line) of the position counter. As a result, the count value Cp of the position counter is corrected so as to be a value (solid line) corresponding to the actual rotation angle of the brushless motor 25 as indicated by an arrow B in FIG.

  As described above, in the present embodiment, even when the detected rotation angle MA of the brushless motor 25 does not coincide with the actual rotation angle, the detected rotation angle MA is obtained through the correction of the count value Cp of the position counter described above. And the actual rotation angle are resolved. For this reason, a decrease in the control accuracy for the rotation angle of the brushless motor 25 due to the detected rotation angle MA of the brushless motor 25 deviating from the actual rotation angle, and a decrease in the control accuracy for the drive state of the variable valve mechanism 14. Can be suppressed.

  If the correction value Kcp is temporarily added to the count value Cp at the time of correcting the count value Cp of the position counter described above, the detected rotation angle MA changes suddenly at the time of the addition, and the detected rotation angle MA and the target rotation angle TMA. Therefore, the brushless motor 25 is driven to set the difference to “0”, which may cause a sudden change in the rotational torque. As a result, the drive state of the variable valve mechanism 14 changes suddenly and the intake air amount of the internal combustion engine 1 changes suddenly, which may cause a sudden change (torque shock) in the output torque of the internal combustion engine 1.

  Based on this point, in the present embodiment, when the correction value Kcp is added to the count value Cp of the position counter, the correction value Kcp is gradually added to the count value Cp, thereby correcting the count value Cp. A sudden change in the detected rotation angle MA is avoided. Specifically, the process of correcting the count value Cp of the position counter by a predetermined value α every predetermined time period Tk is repeatedly executed until the total amount of the correction amount becomes equal to the absolute value of the correction value Kcp. The

  By the way, in the apparatus of the present embodiment, when the actual rotation angle of the brushless motor 25 and the detected rotation angle MA do not coincide with each other, if the actual rotation angle becomes the limit operating angle, the detected rotation angle MA is In spite of the angle that allows the brushless motor 25 to be rotated instead of the limit operating angle, the brushless motor 25 cannot be rotated in a specific direction. Therefore, if the above-described abnormality determination is executed at this time, it is erroneously determined that all of the (condition 1) to (condition 3) are satisfied and the motor is locked.

  In addition, in the present embodiment, when the detected rotation angle MA deviates from the actual rotation angle, the count value Cp of the position counter is corrected so that the detected rotation angle MA gradually shifts to the actual rotation angle. For this reason, the period until the detected rotation angle MA and the actual rotation angle coincide with each other tends to be long. Therefore, there is a higher possibility that the motor lock state is erroneously determined as compared with the configuration in which the count value of the position counter is corrected so that the detected rotation angle MA temporarily shifts to the actual rotation angle.

  Therefore, in the present embodiment, when it is determined that the detected rotation angle MA and the actual rotation angle do not match, the detected rotation angle MA and the actual rotation angle are obtained by correcting the count value Cp of the position counter. Execution of the abnormality determination is prohibited until they coincide.

Hereinafter, details of a process (correction process) for correcting the count value Cp of the position counter including a process for prohibiting the execution of the abnormality determination will be described with reference to FIGS. 9 and 10.
9 and 10 are flowcharts showing specific processing procedures of the correction processing, and a series of processing shown in these flowcharts is performed by the electronic control unit 30 to generate edge of pulse signals from the position sensors S4 and S5. It is executed every predetermined cycle shorter than the cycle.

  As shown in FIG. 9, in this process, first, it is determined whether or not the correction execution flag is turned off (step S201). The correction execution flag is turned off when it is determined that the detected rotation angle MA matches the actual rotation angle (correction value Kcp = “0”), and the detected rotation angle MA and the actual rotation angle are determined. Is a flag that is turned on when it is determined that they do not match (correction value Kcp ≠ “0”).

Here, when the correction execution flag is turned off (step S201: YES), the above-described process (a) is executed (steps S202 to S204).
That is, first, when the edge of the pulse signal from the electrical angle sensors S1 to S3 occurs (step S202: YES), the count value Cp of the position counter at this time is stored as the count value Cpt at the time of the current edge generation. At the same time, the stored count value Cpt is stored as the count value Cpl at the previous edge generation (step S203). Thereafter, a difference ΔCp (= Cpt−Cpl) between the count values Cpt and Cpl is calculated (S204).

Next, the processes (b) and (c) described above are executed (steps S205 to S209).
That is, first, the rotational state of the brushless motor 25 is determined based on the change direction of the count value Ce of the electrical angle counter at the time of the previous edge generation and the current edge generation of the pulse signals from the electrical angle sensors S1 to S3. Determination is made (steps S205 and S206). If the brushless motor 25 is in the normal rotation state (step S205: YES), “4” is set as the normal value J (step S207). On the other hand, when the brushless motor 25 is in the reverse rotation state (step S205: NO and step S206: YES), “−4” is set as the normal value J (step S208). On the other hand, when the brushless motor 25 is in the rotationally reversed state (step S205: NO and step S206: NO), “0” is set as the normal value J (step S209).

Thereafter, a deviation amount (= J−ΔCp) of the difference ΔCp from the normal value J is calculated, and the deviation amount is set as a correction value Kcp (step S210).
Then, after the correction value Kcp is set in this way, processing for adding the correction value Kcp to the count value Cp of the position counter is executed (steps S211 to S218 in FIG. 10).

  Specifically, when the correction value Kcp is a positive value (Kcp> 0) (step S211: YES), at the correction timing every predetermined period Tk (step S212: YES), the count value Cp of the position counter Is added to the predetermined value α (step S213), and the predetermined value α is subtracted from the correction value Kcp (step S214).

  On the other hand, when the correction value Kcp is a negative value (Kcp <0) (step S211: NO and step S215: YES), the position counter counts at the correction timing for each predetermined period Tk (step S216: YES). The predetermined value α is subtracted from the value Cp (step S217), and the predetermined value α is added to the correction value Kcp (step S218).

  The correction timing (steps S212 and S216) means that the predetermined period Tk has elapsed after the correction value Kcp has been set, or that the predetermined period Tk has elapsed since the addition or subtraction of the predetermined value α has been performed. Judgment is made with Therefore, through this processing, the count value Cp of the position counter is added / subtracted by a predetermined value α every predetermined period Tk, and the count value Cp is gradually changed to a value corresponding to the actual rotation angle of the brushless motor 25. It becomes like this.

  Here, the transition of the count value Cp of the position counter accompanying the above-described correction differs depending on the setting period of the predetermined period Tk and the predetermined value α. Specifically, the count value Cp of the position counter changes more gradually as the predetermined period Tk is set longer and as the predetermined value α is set smaller. In the present embodiment, the predetermined period Tk and the predetermined value α are set to a time and a value that do not cause a sudden change in the intake air amount of the internal combustion engine 1 that causes the above-described torque shock. Specifically, a time equal to the time between edges immediately before the pulse signals from the position sensors S4 and S5 is set as the predetermined period Tk, and “1” is set as the predetermined value α.

Then, each time the count value Cp of the position counter is corrected in this way, it is determined whether or not the correction value Kcp has become “0” (step S219).
When the correction value Kcp is not “0” (step S219: NO), the correction execution flag is turned on (step S220). Therefore, in this case (step S201 in FIG. 9: NO), the process of correcting the count value Cp of the position counter (steps S211 to S218 in FIG. 10) is repeatedly executed.

  In this case, the determination prohibition flag is turned on (step S221). This determination prohibition flag is a flag that prohibits execution of the above-described abnormality determination when this is turned on. Therefore, in this case, execution of abnormality determination is prohibited.

  Thereafter, when this process is repeatedly executed and the correction value Kcp becomes “0” (step S219: YES), the correction execution flag is turned “off” (step S222). In this case, the count value Cp of the position counter is corrected until the correction value Kcp newly set through the processing of steps S202 to S210 is not “0” (step S211: NO and step S215: NO). Processing (steps S212 to S214, steps S216 to S218) to be performed is not executed.

In this case, the determination prohibition flag is operated to “off” (step S223), and thereafter, the abnormality determination is permitted.
Hereinafter, the processing mode of the above-described correction processing will be specifically described with reference to FIG.

  FIG. 11 is a timing chart showing an example of the processing mode of the correction process. 11, (a) and (b) show changes in the output signals of the position sensors S4 and S5, (c) shows changes in the count value Ce of the electrical angle counter, and (d) shows the brushless motor 25. (E) shows the transition of the count value Cp of the position counter during the reverse rotation.

  First, during the forward rotation of the brushless motor 25, when noise enters the detection signal of the position sensor S4 ((a) in the figure) (timing T23 to T25), immediately after that, the count value Ce (c (c) in the figure (c)). )) Changes (timing T26), the above-described deviation “J− (Cpt−Cpl) = 4” is set as the correction value Kcp.

  Then, in order to correct the count value Cp of the position counter by the correction value Kcp, a predetermined value α is added to the count value Cp every predetermined period Tk. Thus, every time the predetermined value α is added, the count value Cp of the position counter (the value indicated by the two-dot chain line in FIG. 4D) corresponds to the actual rotation angle of the brushless motor 25 (FIG. 4D). Gradually approach the value indicated by the solid line.

  Such correction of the count value Cp is repeatedly executed until the total value of the predetermined value α added to the count value Cp of the position counter becomes equal to the absolute value of the correction value Kcp (timing T26 to T27). When the total value becomes equal to the absolute value of the correction value Kcp (timing T27), the count value Cp of the position counter becomes equal to the value corresponding to the actual rotation angle of the brushless motor 25.

  On the other hand, during the reverse rotation of the brushless motor 25, when noise enters the detection signal of the position sensor S4 ((a) in the figure) (timing T25 to T23), the count value Ce of the electric angle counter (c (c )) Changes (timing T22), the above-described deviation “J− (Cpt−Cpl) = − 4” is set as the correction value Kcp.

  Then, a predetermined value α is subtracted from the count value Cp every predetermined period Tk so as to correct the count value Cp of the position counter by the correction value Kcp. Thus, each time the predetermined value α is subtracted, the count value Cp of the position counter (value indicated by a two-dot chain line in FIG. 5E) corresponds to the actual rotation angle of the brushless motor 25 (FIG. 5E). Gradually approach the value indicated by the solid line.

  Such correction of the count value Cp is repeatedly executed until the total value of the predetermined value α subtracted from the count value Cp of the position counter becomes equal to the absolute value of the correction value Kcp (timing T22 to T21). When the total value becomes equal to the absolute value of the correction value Kcp (timing T21), the count value Cp of the position counter becomes equal to the value corresponding to the actual rotation angle of the brushless motor 25.

  Thus, even if the detected rotation angle MA and the actual rotation angle do not coincide with each other by executing the correction processing according to the present embodiment, the mismatch is detected by the detected rotation angle MA (more precisely, It is eliminated through correction of the count value Cp) of the position counter. Therefore, it is possible to suppress a decrease in control accuracy of the brushless motor 25 and a decrease in control accuracy of the variable valve mechanism 14 due to the detected rotation angle MA deviating from the actual rotation angle.

  Further, since the detected rotation angle MA (more precisely, the count value Cp of the position counter) is corrected so that the detected rotation angle MA gradually changes, a sudden change in the rotational torque of the brushless motor 25 due to the correction is avoided. It is possible to suppress the occurrence of a torque shock due to a sudden change in the intake air amount of the internal combustion engine 1.

  Further, after it is found that the detected rotation angle MA and the actual rotation angle do not match (correction value Kcp ≠ “0”), the detected rotation angle MA and the actual rotation angle come to match. During the period until (timing T26 to T27 during normal rotation, timing T22 to T21 during reverse rotation), the execution of abnormality determination is prohibited. For this reason, even during the above period, even if all of the above (Condition 1) to (Condition 3) are satisfied, it is not determined that the motor is in the locked state, and erroneous detection of the locked state of the motor is accurately performed. Can be suppressed.

As described above, according to the present embodiment, the effects described below can be obtained.
(1) When it is determined that the detected rotation angle MA and the actual rotation angle do not coincide with each other, the count value Cp of the position counter is corrected so as to make the rotation angles coincide with each other. During the period until the actual rotation angle matches, the execution of abnormality determination for determining whether or not the motor lock state has occurred is prohibited. Therefore, it is possible to suppress a decrease in the control accuracy of the rotation angle of the brushless motor 25 and a decrease in the control accuracy of the variable valve mechanism 14 due to the detected rotation angle MA deviating from the actual rotation angle, and erroneous determination of the motor lock state Can be accurately suppressed.

  (2) Every time an edge of a pulse signal from the plurality of electrical angle sensors S1 to S3 is generated, a difference ΔCp between the count value Cpl of the position counter at the time of the previous edge generation and the count value Cpt of the position counter at the time of the current edge generation is calculated. It can be determined that the detected rotation angle MA and the actual rotation angle are inconsistent when the difference ΔCp is different from the normal value J. Moreover, the difference ΔCp can be obtained using the electrical angle sensors S1 to S3 attached to the brushless motor 25 for driving without adding a new sensor or the like for obtaining the difference ΔCp.

  (3) Since the count value Cp of the position counter is corrected by the amount of deviation from the normal value J of the difference ΔCp, it corresponds to the actual rotation angle of the brushless motor 25 of the count value Cp of the position counter. The deviation from the value can be accurately corrected, and the deviation of the detected rotation angle MA from the actual rotation angle can be accurately corrected.

  (4) Since the count value Cp of the position counter is corrected so that the detected rotation angle MA gradually shifts to the actual rotation angle, there is a high possibility that the motor lock state is erroneously determined. The erroneous determination can be accurately suppressed.

The embodiment described above may be modified as follows.
The condition for determining that the state is malfunctioning is detected, for example, by adopting a condition that the state where the deviation between the detected rotational angle MA and the target rotational angle TMA is a predetermined value or more is continued for a predetermined period. The condition can be appropriately changed as long as it can be determined that the detected rotation angle MA is almost unchanged in a situation where the rotation angle MA and the target rotation angle TMA do not match.

  The method for determining whether or not the actual rotation angle of the brushless motor 25 matches the detected rotation angle MA is not limited to the method of determining that the difference ΔCp and the normal value J do not match, and can be arbitrarily changed. is there.

  For example, the ratio (Cpl / Cpt or Cpt / Cpl) between the count value Cpl at the time of the previous edge generation and the count value Cpt at the time of the current edge generation is calculated, and the ratio is different from the ratio at the normal time. It may be determined that the detected rotation angle MA and the actual rotation angle do not match. In this way, the actual relationship between the count values Cpl and Cpt is obtained, and the presence / absence of coincidence between the detected rotation angle MA and the actual rotation angle is determined by comparing the obtained actual relationship with a normal relationship. Can do.

  The correction process is a process in which there is a time lag from when it is determined that the detected rotation angle MA does not match the actual rotation angle until the detected rotation angle MA matches the actual rotation angle. Any change is possible. As such correction processing, for example, processing for learning the learning value Pr can be employed. Further, if the process has such a time lag, a correction process may be executed in which correction for eliminating the difference between the detected rotation angle MA and the actual rotation angle is performed at one time.

  The present invention provides a correction process for correcting a phenomenon in which the power supply to the position detection system is stopped for a very short time, that is, a so-called instantaneous interruption phenomenon, and the detected rotation angle deviates from the actual rotation angle. It can also be applied to an executing device. In the same configuration, it may be determined that the detected rotation angle and the actual rotation angle do not coincide with each other when the instantaneous interruption phenomenon occurs.

  Normally, the value calculated by the electronic control unit is stored in a volatile memory, so when an instantaneous interruption occurs, the count value of the position counter, which is such a calculated value, disappears, and the detected rotation angle is actually It will deviate from the rotation angle. Even in such a case, the detected rotation angle can be corrected so that the detected rotation angle matches the actual rotation angle by learning the count value of the position counter at the limit rotation angle of the brushless motor. Further, in such a device, the period from when it is determined that the detected rotation angle and the actual rotation angle do not coincide with each other until the rotation angles coincide (for example, the learning is completed after the occurrence of the instantaneous interruption phenomenon). By prohibiting the execution of the abnormality determination, the erroneous determination of the malfunction state can be accurately suppressed.

  The present invention can also be applied to a motor control device that controls driving of an electric rotating machine other than a brushless motor, such as a motor control device that controls driving of a stepping motor.

  The present invention also relates to an internal combustion engine having a variable valve mechanism that makes the valve characteristics of an exhaust valve variable, and also to a motor control device that controls the rotation of an electric rotary machine used to drive the variable valve mechanism. Can be applied.

  -The motor control apparatus concerning this invention is applicable also to electric rotating machines other than the electric rotating machine used for the drive of the variable valve mechanism which makes the valve characteristic of an engine valve variable. As such an electric rotating machine, for example, an exhaust gas recirculation mechanism that recirculates exhaust gas from the exhaust passage to the intake passage through drive control of a flow path control valve provided in the middle of the communication passage connecting the exhaust passage and the intake passage. Examples of the internal combustion engine include an electric rotating machine used for driving control of the flow path control valve.

  The present invention can be applied not only to a motor control device that controls driving of an electric rotating machine but also to a motor control device that controls driving of a hydraulically driven rotating machine. Further, the present invention can be applied not only to a motor control device that controls driving of a rotating machine, but also to a motor control device that controls driving of a motor in which a movable portion moves linearly.

1 is a cross-sectional view showing a cross-sectional structure around a cylinder head of an internal combustion engine to which a motor control device according to an embodiment embodying the present invention is applied. 1 is a schematic diagram showing a drive mechanism that drives a variable valve mechanism according to the embodiment and a control device that controls the drive of the drive mechanism. (A)-(h) The timing chart which shows transition of the output value of various sensors, and transition of the count value of various counters changed according to the change of these output signals. The flowchart which shows the specific physical procedure of a count process. (A) Table showing the relationship between the count value of the electrical angle counter and the output pattern of the pulse signal from each electrical angle sensor, (b) Table showing the relationship between the count value of the position counter and the output pattern from each position sensor . (A)-(e) The timing chart which shows an example of transition of the count value of a position counter at the time of noise generation. (A) And (b) Table which shows the addition / subtraction mode of the counter value of the position counter according to the signal from the position sensor at the timing T12, T13, T14 of FIG. The table | surface which shows the relationship between the change direction of the count value of an electrical angle counter, and the rotation state of a brushless motor. The flowchart which shows the specific process sequence of a correction process. The flowchart which shows the specific process sequence of a correction process. (A)-(e) The timing chart which shows an example of the process aspect of a correction process.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Internal combustion engine, 2 ... Cylinder head, 3 ... Cylinder block, 5 ... Piston, 6 ... Combustion chamber, 7 ... Intake passage, 8 ... Exhaust passage, 9 ... Intake valve, 10 ... Exhaust valve, 11 ... Intake camshaft, 11a ... intake cam, 12 ... exhaust camshaft, 12a ... exhaust cam, 14 ... variable valve mechanism, 15 ... rocker shaft, 16 ... control shaft, 17 ... input arm, 18 ... output arm, 20 ... spring, 21 ... rocker arm , 22 ... Rush adjuster, 24 ... Valve spring, 25 ... Brushless motor, 26 ... Conversion mechanism, 27, 28 ... Stopper member, 30 ... Electronic control unit, 30a ... Non-volatile memory, 31 ... Accelerator position sensor, 32 ... Rotational speed Sensor, 33 ... Ignition switch, S1, S2, S3 ... Electrical angle sensor, S4, S5 ... Position sensor Support.

Claims (5)

A stopper member that restricts a change in the operating position of the motor at a limit operating position through contact with a portion that operates as the motor is driven, and a position sensor that periodically changes as the operating position of the motor changes. And a position detection system for detecting the operation position of the motor based on the output signal, and the motor based on the detection operation position so that the detection operation position detected by the position detection system becomes a target operation position. The feedback control of the operation position is performed, and the abnormality determination is performed to determine that the operation is in a defective state when the detection operation position does not change in a situation where the detection operation position does not coincide with the target operation position. A motor control device,
The presence or absence of a match between the detected motion position and the actual motion position is determined. When it is determined that the motion positions do not match, the detection motion position is corrected to match the motion positions, and through the correction, the detection motion position is corrected. Execution of the abnormality determination is prohibited until the detected operation position matches the actual operation position. The motor control device according to claim 1,
The motor is an electric rotating machine and has a plurality of electrical angle sensors that periodically output pulse signals that are out of phase with each other as the motor rotates. Is driven through switching,
The position detection system includes a plurality of position sensors that individually output pulse signals that are out of phase with each other as the motor rotates, and the edge intervals of the pulse signals from the position sensors are the plurality of positions. It is set shorter than the edge interval of the pulse signal from the electrical angle sensor, and detects the operating position of the motor based on the count value obtained by counting the edges of the pulse signals from the plurality of position sensors,
The inconsistency is obtained by obtaining an actual relationship between the count value at the time of the previous edge generation and the count value at the time of the current edge generation for each edge generation of the pulse signals from the plurality of electrical angle sensors. The motor control device is characterized in that it is determined that the actual relationship is different from the normal relationship. The motor control device according to claim 2,
Correcting the detection operation position is performed by changing the count value by an amount corresponding to a deviation amount of the actual relationship from the normal relationship. The motor control device according to claim 3,
The motor control device characterized by gradually changing the count value so that the detection operation position gradually shifts to the actual operation position. The motor control device according to any one of claims 1 to 4, wherein the motor is used for driving a variable valve mechanism that changes a valve characteristic of an engine valve of an internal combustion engine.

Images