JP2017093071A - Motor control device and optical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor control device capable of controlling an advance value so as to generate a maximum torque and an optical device.SOLUTION: The motor control device includes: a motor provided with a rotor on which magnetic poles are formed at every predetermined angle; first detecting means for detecting a rotational position of the rotor, second detecting means having the resolution of detection higher than that of the first detecting means for detecting the rotational position of an output axis of the motor; and control means for controlling motor driving by using an advance value on the basis of an output signal of the second detecting means at the timing when an output signal of the first detecting means is output.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a motor control device and an optical apparatus.

  Patent Document 1 discloses a motor drive device that includes a detection element that detects the position of a magnet rotor (hereinafter referred to as a rotor), determines energization conditions for energizing a drive coil according to the detection result, and drives the motor. Yes.

JP 2013-99055 A

  It is known that maximum torque is generated by driving the motor with an advance value of 90 ° in electrical angle (the phase difference between the timing when the drive coil is energized and the timing when the pole piece is excited, ie, the advance phase angle). Yes. However, in the three-phase brushless motor disclosed in Patent Document 1, since the rotor position detection resolution is 60 ° in electrical angle, the advance value fluctuates between 60 ° and 120 °, and the advance angle. An error occurs for a value of 90 °. Further, in the motor drive device of Patent Document 1, the advance value is not controlled while the motor is being driven.

  In view of such a problem, an object of the present invention is to provide a motor control device and an optical apparatus that can control an advance value so as to generate a maximum torque.

  A motor control device according to one aspect of the present invention includes a motor including a rotor in which magnetic poles are formed at predetermined angles, a first detection unit that detects a rotational position of the rotor, and a first detection unit. A second detection means having a detection resolution higher than the detection resolution and detecting the rotational position of the output shaft of the motor; and an output of the second detection means at a timing at which an output signal of the first detection means is output. Control means for controlling driving of the motor using an advance value based on the signal.

  ADVANTAGE OF THE INVENTION According to this invention, the motor control apparatus and optical apparatus which can control an advance value so that a maximum torque may be generated can be provided.

1 is a configuration diagram of a motor control device (Example 1). FIG. It is a timing chart figure of a 1st position detection means and a 2nd position detection means. It is a phase relationship figure of rotor position detection and an energization waveform. It is explanatory drawing of the energization waveform of a drive coil. It is a timing chart of the control method of an advance value. 3 is a flowchart illustrating control processing (Example 1). (Example 2) which is a block diagram of a motor control apparatus. It is a flowchart which shows a control process (Example 2). (Example 3) which is a block diagram of a motor control apparatus. 10 is a flowchart illustrating a control process (Example 3). (Example 4) which is a block diagram of a motor control apparatus. 10 is a flowchart illustrating a control process (Example 4). 10 is a flowchart illustrating a speed deviation detection control process (Example 4). (Example 5) which is a block diagram of a motor control apparatus. (Example 6) which is a block diagram of a motor control apparatus. It is a flowchart which shows a control process (Example 6). (Example 7) which is a block diagram of a motor control apparatus. It is a flowchart which shows a control process (Example 8). (Example 9) which is a block diagram of an optical apparatus provided with a motor control apparatus.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each figure, the same members are denoted by the same reference numerals, and redundant description is omitted. In each embodiment, a motor control device that controls a two-phase brushless motor (hereinafter referred to as a motor) will be described as an example.

  FIG. 1 is a configuration diagram of a motor control device according to the present embodiment. FIG. 2A is a timing chart of the first position detection means (first detection means) 101 and the second position detection means (second detection means) 107. FIG. 2B is a phase relationship diagram between rotor position detection and energization waveforms. FIG. 3 is an explanatory diagram of the energization waveform of the drive coil unit 5.

  In FIG. 1, the motor unit 10 is a portion surrounded by a two-dot chain line, and includes a position detection unit 1, a rotor 2, a magnetoresistive element 3, an encoder magnet 4, a drive coil unit 5, and an output shaft 6. The position detection unit 1 includes Hall elements 1 a and 1 b that detect the rotational position of the rotor 2. The hall elements 1a and 1b are arranged along the outer periphery of the rotor 2 so as to have a phase difference of 90 ° in electrical angle. Magnetic poles are formed on the rotor 2 at certain angles.

  When the rotor 2 rotates, the first position detection unit 101 acquires output signals from the Hall elements 1 a and 1 b and outputs signals based on these output signals to the timing pulse output unit 102 and the control unit 103. Based on the signal from the first position detection unit 101, the control unit 103 outputs to the energization unit 106 an output signal that is an energization waveform having different phases for energizing the drive coils 5 a and 5 b of the drive coil unit 5. In the present embodiment, the control unit 103 reads the energization waveform for the drive coils 5a and 5b from the storage unit (not shown) using the energization waveform condition based on the signal from the first position detection unit 101. The energizing means 106 supplies energized waveforms having different phases to the drive coils 5a and 5b. In this embodiment, the energizing means 106 supplies a sine wave voltage, but the present invention is not limited to this.

  The phase of the energization waveform is set by the electrical angle (center value θ) at the center of the regions θ1 to θ4 shown in FIG. 2A. Specifically, the central value θ is set to 45 ° in the region θ1 (0 to 90 ° in electrical angle). In the region θ2 (90 ° to 180 ° in electrical angle), the center value θ is set to 135 °. In the region θ3 (electrical angle 180 ° to 270 °), the center value θ is set to 225 °. In the condition θ4 (electrical angle 2270 ° to 360 °), the center value θ is set to 315 °.

  In FIG. 2B, the energization waveform to the drive coil 5a has a lead phase of 90 ° in electrical angle compared to the detection waveform of the magnetic pole by the Hall element 1a. Similarly, the energization waveform to the drive coil 5b has a lead phase of 90 ° in electrical angle compared to the detection waveform of the magnetic pole by the Hall element 1b. Therefore, the magnetic poles of the rotor 2 and the drive coil unit 5 always generate a rotational force by a signal acquired from the first position detection means 101. That is, the advance value of each energization waveform condition in the regions θ1 to θ4 is 90 °. However, since the position detection resolution of the rotor 2 is 90 °, the advance value is accurately 90 ° ± 45 °. It fluctuates within the range of 45 ° to 135 °.

  The timing pulse output unit 102 outputs a signal based on the output signal of the first position detection unit 101 (hereinafter referred to as a timing pulse) to the measurement unit 104. The second position detecting means 107 uses a magnetoresistive element 3 and a multi-phase magnetized encoder magnet 4 that is coaxially fixed to the output shaft 6 so as to rotate integrally with the output shaft 6. Get the signal. As shown in FIG. 2A, the second position detection unit 107 outputs a two-phase rectangular wave (hereinafter referred to as an encoder pulse signal) indicating the rotation direction and the rotation amount from the phase difference between the acquired two-phase signals. It outputs to the means 108. The count pulse output means 108 outputs a pulse signal (hereinafter referred to as a count pulse) obtained by further multiplying the encoder pulse signal by 4 to the measurement means 104 and the control means 103. The measuring means 104 measures the number of count pulses for each timing pulse and records the measured number of count pulses in a storage unit (not shown).

  The control means 103 outputs an energization waveform based on the acquired count pulse to the energization means 106. The energization means 106 supplies voltages V · sin (θ + δθ) and V · cos (θ + δθ) to the drive coils 5a and 5b, respectively. Note that θ is the phase of the energization waveform of the drive coil unit 5, and δθ is an electrical angle corresponding to the cycle of one count pulse. That is, every time the control means 103 acquires the count pulse, the phase of the supply voltage to the drive coil unit 5 is updated as θ + δθ as shown in FIG. The electrical angle (angular resolution) detectable by the count pulse is 9 °, which is 10 times the timing pulse as shown in FIG.

  Next, a method for controlling the advance value using the output signals acquired from the first position detecting means 101 and the second position detecting means 107 will be described. FIG. 3 shows a state where the advance value is maintained at 90 ° and the motor is rotating. As shown in FIG. 3, the number of gunt pulses at the timing of the first timing pulse after the start of driving of the motor is five pulses. That is, when the number of count pulses at the timing of the timing pulse is 5, the apparatus can be started up with an advance value of 90 °. Then, by sequentially updating the phase of the energization waveform (θ = θ + δθ) every time the count pulse is measured, the motor can be driven with the advance value of 90 °.

  However, since the position of the rotor 2 exists between 45 ° and 135 ° in advance before starting the motor drive, the number of count pulses at the timing of the first timing pulse varies between 0 and 10 pulses. . A case where the optimum advance angle value is not obtained will be described with reference to FIG. FIG. 4 is a timing chart of the advance value control method. In FIG. 4, the number of count pulses at the timing of the first timing pulse is two pulses. In the present embodiment, the control means 103 can control the advance value to 90 ° by updating the phase of the energization waveform using the following equation. Here, n is the number of count pulses.

θ = θ + (5-n) · δθ (1)
That is, in the example shown in FIG. 4, the correction value (= (5-n) · δθ) is 27 °, and the advance value is set to 63 ° at the time of startup. In FIG. 4, the processing is set to be executed almost simultaneously at the timing of the timing pulse.

  Next, an advance value control process according to this embodiment will be described with reference to FIG. FIG. 5 is a flowchart showing the advance value control process of the present embodiment.

  In step S101, data temporarily stored in the motor control device is initialized, and in step S102, the rotation direction of the motor is set. The rotation direction may be set in advance or may be set according to an instruction from the outside. In step S103, the position detector 1 detects the rotational position of the rotor 2, and in step S104, the control means 103 sets energization waveform conditions. In step S105, the energizing means 106 supplies voltages V · sin (θ) and V · cos (θ) to the drive coils 5a and 5b, respectively.

  In step S106, it is determined whether there is a count pulse. If no count pulse exists, the process proceeds to step S107, and if present, the process proceeds to step S108. In step S107, it is determined whether or not a timing pulse exists. If no timing pulse exists, the process proceeds to step S103, and if present, the process proceeds to step S111. The control means 103 measures the count pulse in step S108, and sets the energization waveform condition so that the phase of the energization waveform is advanced by an electrical angle of 9 ° for each measured count pulse in step S109.

  In step S110, it is determined whether or not a timing pulse exists. When there is no timing pulse, the process proceeds to step S108, and when there is a timing pulse, the process proceeds to step S111. In step S111, the count pulse number is stored at the timing when the measuring means 104 receives the timing pulse. In step S112, the control means 103 calculates the advance value correction value using the above-described equation (1).

  In step S109, it is determined whether to stop the motor rotation. When continuing motor rotation, it progresses to step S114, and when stopping motor rotation, it progresses to step S115. In step S114, the control means 103 sets the energization waveform condition, and the process of continuing the motor rotation is continued. In step S115, energization to the drive coil unit 5 is maintained. In step S116, a timer (not shown) measures time, and in step S117, it is determined whether or not the time measured in step S116 is longer than a predetermined time during which the motor can be reliably stopped. If the time measured in step S116 is shorter than the predetermined time, the process proceeds to step S116, and if longer than the predetermined time, the process proceeds to step S118. In step S118, the control means 103 stores the energization waveform condition, and then stops energization to the drive coil unit 5. In this embodiment, a timer is used to stop the motor. However, it is determined whether the motor is rotating based on whether there is a count pulse. The energization to the unit 5 may be stopped.

  As described above, the motor control device of this embodiment can control the advance value so as to generate the maximum torque.

  FIG. 6 is a configuration diagram of the motor control device of this embodiment. A description of the same configuration as in the first embodiment will be omitted, and a different configuration will be described.

  In FIG. 6, the speed calculation means 109 measures the cycle (δt) of the count pulse acquired from the count pulse output means 108 and calculates the angular speed (ω = δθ / δt). The speed change detection means (change amount calculation means) 110 detects the change value of the angular velocity calculated by the speed calculation means 109. The control method selection unit 111 determines whether or not the change value detected by the speed change detection unit 110 is larger than a predetermined value, and selects a motor driving method according to the determination result.

  Next, the control processing of the present embodiment will be described with reference to FIG. FIG. 7 is a flowchart showing the control processing of this embodiment. In FIG. 7, the steps having the same step numbers as those in FIG. 5 are the same as those in FIG. 5, and thus detailed description thereof is omitted.

  In step S201, it is determined whether the change value of the angular velocity detected by the velocity change detection unit 110 is greater than a predetermined value. If the change value is larger than the predetermined value, the process proceeds to step S202. If the change value is smaller than the predetermined value, the process proceeds to step S203. After the energization waveform condition is set in step S202, the process proceeds to step S105, and the motor rotation is continued in a state where the advance value correction process is executed. In step S203, the position detector 1 detects the rotational position of the rotor 2, and in step S204, the control means 103 selects an energization waveform pattern. In step S205, the energization means 106 supplies voltages V · sin (θ) and V · cos (θ) to the drive coils 5a and 5b, respectively. That is, if the change value is larger than the predetermined value in step S201, the motor rotation is continued without executing the advance value correction process.

  As described above, in the motor control apparatus of this embodiment, the control method selection unit 111 rotates the motor while correcting the advance value in a region where the speed change in the acceleration region is large from the time of startup, and the speed change is small. In the region, the motor is rotated without correcting the advance value. Therefore, the advance value can be controlled so that the maximum torque is generated in the region where the speed change is large, and the load of the control circuit including the CPU mounted on the control system is reduced in the region where the speed change is small, thereby reducing the power consumption. be able to. When there is a large load fluctuation or when the generation of the maximum torque is maintained, the function of the control method selection unit 111 may be turned off.

  FIG. 8 is a configuration diagram of the motor control device of this embodiment. A description of the same configuration as in the first and second embodiments will be omitted, and a different configuration will be described.

  The target speed setting unit 112 sets a target speed. The speed deviation calculating means 113 calculates a speed deviation δω = (ωa−ω) from the target speed (ωa) set by the target speed setting means 112 and the actual detected speed (ω) calculated by the speed calculating means 109. The PID calculation unit 114 performs the PID control using the speed deviation δω calculated by the speed deviation calculation unit 113, thereby setting the energization waveform condition that makes the rotation speed of the motor a target speed.

  Next, the control processing of the present embodiment will be described with reference to FIG. FIG. 9 is a flowchart showing the control processing of this embodiment. In FIG. 9, the steps with the same step numbers as those in FIGS. 5 and 7 are the same as the steps in each drawing, and detailed description thereof is omitted.

  In step S301, the target speed setting means 112 sets the target speed ωa. In step S302, the speed calculation unit 109 calculates the rotation speed of the motor. In step S303, the speed deviation calculating means 113 calculates a speed deviation δω. In step S304, it is determined whether the calculated speed deviation δω is smaller than a predetermined value. The predetermined value is set according to the load condition and use condition of the motor control device. When the speed deviation δω is smaller than the predetermined value, the process proceeds to step S106, and when larger than the predetermined value, the process proceeds to step S305. In step S305, the PID calculation unit 114 sets an energization waveform condition at which the motor speed becomes the target speed.

  As described above, in the motor control device of the present embodiment, the motor speed is controlled by changing the input power to the drive coil in accordance with the deviation between the target speed and the actual speed. Therefore, the advance value can be controlled so as to generate the maximum torque, and the input power to the drive coil can be set to the minimum necessary input power.

  FIG. 10 is a configuration diagram of the motor control device of the present embodiment. A description of the same configuration as in the first to third embodiments will be omitted, and a different configuration will be described.

  The speed calculation selection means 115 selects whether to use a count pulse or a timing pulse as a signal for speed detection according to the speed deviation δω calculated by the speed deviation calculation means 113. Since the resolution of the count pulse is 10 times that of the timing pulse, it is possible to maintain a constant speed with high accuracy even when the load fluctuation is large and the speed deviation δω is large if control is performed in the cycle of the counter pulse. . On the other hand, when the load fluctuation is small and the speed deviation δω is small, the constant speed can be maintained with high accuracy even if the control is performed at the timing pulse cycle.

  Next, the control processing of the present embodiment will be described with reference to FIGS. 11A and 11B. FIG. 11A is a flowchart showing the control processing of this embodiment. FIG. 11B is a flowchart showing the speed deviation detection control process of the present embodiment. In FIG. 11A and FIG. 11B, the same step numbers as those in FIG. 5, FIG. 7, and FIG.

  In step S401, it is determined whether or not the speed deviation δω is smaller than a predetermined value (the initial set value is the first predetermined value). When the speed deviation δω is smaller than the first predetermined value, the process proceeds to step S402, and when larger than the first predetermined value, the process proceeds to step S405. In step S402, the predetermined value used for comparison with the speed deviation δω is changed from the first predetermined value to a second predetermined value that is larger than the first predetermined value. In step S403, the speed calculation selection means 115 selects a timing pulse as a signal for speed detection. In step S404, the speed deviation detection control shown in FIG. 11B is executed. In step S405, the first predetermined value is maintained as the predetermined value used when compared with the speed deviation δω. In step S406, the speed calculation selection means 115 selects a count pulse as a signal for speed detection.

  Here, the speed deviation detection control will be described with reference to FIG. 11B. In step S411, it is determined whether a timing pulse exists. If no timing pulse exists, the process proceeds to step S103, and if present, the process proceeds to step S412. The control means 103 measures the timing pulse in step S412, and sets the energization waveform condition so that the phase of the energization waveform is advanced by an electrical angle of 90 ° for each measured timing pulse in step S413. In step S414, the speed calculation means 109 calculates the rotational speed ω of the motor, and in step S415, the speed deviation calculation means 113 calculates the speed deviation δω. In step S416, it is determined whether or not the speed deviation δω is smaller than a second predetermined value. When the speed deviation δω is smaller than the second predetermined value, the process proceeds to step S417, and when larger than the second predetermined value, the process proceeds to step S418. In step S417, the second predetermined value is maintained as the predetermined value used when compared with the speed deviation δω, and in step S418, the predetermined value is changed from the second predetermined value to the first predetermined value.

  As described above, in the motor control device of this embodiment, the motor driving method can be selected according to the speed deviation. Therefore, when the load fluctuation is small and the speed deviation is small, the advance value correction is not executed, so the load on the control circuit including the CPU mounted on the control system is reduced, and the power consumption can be reduced.

  FIG. 12 is a configuration diagram of the motor control device of this embodiment. A description of the same configuration as in the first to fourth embodiments will be omitted, and a different configuration will be described.

  In the motor control apparatus of the present embodiment, the output shaft rotation amount (= rotation number × 360 °) of the motor is set. The rotation amount setting means 116 converts the output shaft rotation amount of the motor into an electrical angle according to the number of magnetic poles of the rotor 2. For example, when the number of magnetic poles of the rotor 2 is 2, the mechanical angle and the electrical angle are equal, but the number of magnetic poles of the rotor 2 is generally multipolarized in many cases. When the number of magnetic poles of the rotor 2 is P, the electrical angle can be obtained by the following equation.

Electrical angle = Output shaft rotation x P / 2 (2)
In this embodiment, the motor control device sets the output shaft rotation amount of the motor, but the output shaft rotation amount may be set by an instruction from the outside.

  The D / A conversion means 117 converts the count pulse obtained from the count pulse output means 108 into an electrical angle with one pulse as the electrical angle δθ (9 °). The rotation amount calculation means 118 measures an electrical angle (number of pulses × δθ). The rotation amount deviation calculating means 119 uses the following equation to calculate the rotation amount deviation (phase difference) from the target rotation amount (electrical angle) set by the rotation amount setting means 116 and the calculated value (electrical angle) of the rotation amount calculating means 118. ) Is calculated.

Rotation amount deviation = target rotation amount-calculated value (3)
The PID calculation unit 120 performs PID control using the rotation amount deviation calculated by the rotation amount deviation calculation unit 119. The phase difference limiting means 121 limits the advance value set by the PID control with a predetermined limit value (hereinafter referred to as a limit value). The absolute value of the advance value that generates the maximum torque is 90 °. If the advance value is set to 90 ° or more, the generated torque may decrease or the generated torque for rotating in the same direction may not be obtained. is there. For this reason, in this embodiment, the limit value is set to ± 90 ° so as to correspond to forward and reverse rotation. When the rotation amount deviation is smaller than the limit value, the calculated value is close to the target rotation amount. Therefore, as the rotation amount deviation decreases, the advance value also decreases. Finally, the rotation amount deviation and the advance value become 0 when the target rotation amount and the calculated value match.

  As described above, in this embodiment, the motor is driven with an advance value that always generates the maximum torque up to the vicinity of the target rotation amount, and from the vicinity of the target rotation amount to the target rotation amount according to the rotation amount deviation. The lead angle value is controlled to drive the motor. Therefore, the motor control device of the present embodiment can reach the target rotation amount at high speed and with high accuracy.

  FIG. 13 is a configuration diagram of the motor control device of this embodiment. A description of the same configuration as in the first to fifth embodiments will be omitted, and a different configuration will be described.

  In the present embodiment, the target speed setting unit 112 acquires the rotation amount deviation calculated by the rotation amount deviation calculation unit 119, and sets the target speed based on the acquired rotation amount deviation. The target speed setting means 112 sets the target speed to the first speed when the rotation amount deviation is larger than a predetermined value, and sets the target speed to a second speed lower than the first speed when the rotation amount deviation is smaller than the predetermined value. Set the speed to Thereafter, in the present embodiment, the control for the target speed described in the third embodiment is executed. Accordingly, the advance value is controlled so that the maximum torque is generated, and the speed control according to the rotation amount deviation is also performed, so that the target rotation amount can be reached at high speed and with high accuracy.

  Next, with reference to FIG. 14, the control process of a present Example is demonstrated. FIG. 14 is a flowchart showing the control processing of this embodiment. In FIG. 14, those given the same step numbers as those in FIGS. 5, 7, 9, and 11 are the same as those in each figure, and thus detailed description thereof is omitted.

  In step S601, a target rotation amount is set. In step S602, the rotation amount deviation calculating unit 119 calculates a rotation amount deviation with respect to the target rotation amount using the above-described equation (3). In step S603, the rotation amount calculation unit 118 calculates the rotation amount (δθ × n [pls]), the rotation amount deviation calculation unit 119 calculates the rotation amount deviation, and in step S604, the PID calculation unit 120 performs PID control. In step S606, the target speed setting means 112 sets a target speed according to the rotation amount deviation. In step S607, the speed calculation means 109 calculates the speed ω, in step S608, the speed deviation calculation means 113 calculates the speed deviation, and in step S609, the PID calculation means 114 performs PID control. In step S610, it is determined whether the rotation amount deviation is smaller than a predetermined value. If larger than the predetermined value, the process proceeds to step S114, the energization waveform condition is updated, and the process proceeds to step S106. When the value is smaller than the predetermined value, the flow of the motor rotation stopping operation (steps S115 to S118 in FIG. 5) described in the first embodiment is executed.

  As described above, in the motor control device of this embodiment, the advance angle value is controlled so as to generate the maximum torque, the target speed is reduced in the vicinity of the target rotation amount, and the advance angle value is set according to the rotation amount deviation. Therefore, the control performance for reaching the target rotation amount is improved.

  FIG. 15 is a configuration diagram of the motor control device of the present embodiment. In the present embodiment, parts different from FIG. 13 of the sixth embodiment will be described.

  When a sudden load fluctuation occurs in the vicinity of the target rotation amount, the closed loop control may become unstable. Therefore, in the present embodiment, when the target rotation amount set by the rotation amount setting unit 116 is smaller than a predetermined value, the open / closed loop selection unit 122 changes from the advance value control (closed loop control) to the rotation direction and rotation amount of the motor. An instruction to switch to the open loop control for controlling is output to the control means 103.

  The predetermined value may be set to one count pulse (δθ). When the target rotation amount is smaller than one pulse, it is impossible to detect the count pulse and measure the rotation amount, so it is necessary to switch the motor control method from closed loop control to open loop control.

  The control means 103 outputs the energization waveform read from the open loop energization waveform data stored therein to the energization means 106. Then, the energization unit 106 energizes the drive coil unit 5 based on the energization waveform acquired from the control unit 103, whereby open loop control is performed.

  Further, the control means 103 changes the energized waveform of the sine wave stored therein in a stepwise manner for each predetermined electrical angle to a target rotation amount from a plurality of open loop energized waveforms for microstep driving with different resolutions. A corresponding energization waveform may be selected. The energizing means 106 is based on the energization waveform acquired from the control means 103 so that the motor is driven every microstep so as to drive the motor every microstep until the motor rotation amount reaches the target rotation amount. The drive coil unit 5 is energized.

  As described above, in the motor control device of this embodiment, the advance value is controlled so that the brushless motor always generates the maximum torque until the vicinity of the target rotation amount. Further, when the target rotation amount is smaller than the predetermined value, the target rotation amount can be reached by open loop control, so that the motor can be driven stably.

  With reference to FIG. 16, the control process of a present Example is demonstrated. FIG. 16 is a flowchart illustrating a control process after the completion of the flow of the motor rotation stop operation described in the first embodiment.

  In step S801, it is determined whether there is a restart command. If there is a restart command, the process proceeds to step S802. In step S802, the energization means 106 energizes the drive coil unit 5 for a predetermined time under the energization waveform condition stored in step S118 before stopping. In step S <b> 803, measurement of the count pulse is started simultaneously with the start of energization of the drive coil unit 5. In some cases, the motor rotates due to some external factor after stopping the rotation of the motor. In this case, the motor rotates slightly after the drive coil unit 5 is energized and count pulses are measured. In step S804, in order to confirm whether or not the position of the rotor 2 has changed since the energization of the drive coil unit 5 was turned off, it is determined whether or not the count pulse to be measured is smaller than a predetermined number. If the count pulse is smaller than a predetermined value (for example, 1 to 2 pulses), it is determined that there is almost no change in the position of the rotor 2, and the advance value is set to 90 ° in step S805. In step S806, the control unit 103 updates the energization waveform condition. On the other hand, if the count pulse is larger than the predetermined value, the position of the rotor 2 is detected in step S807, and the control means 103 sets energization waveform conditions in step S808. In step S809, the energization means 106 energizes the drive coil unit 5.

  As described above, the motor control device according to the present embodiment can be started according to the stopped rotor position.

  FIG. 17 is a configuration diagram of an optical apparatus including the motor control device of this embodiment. The optical device is, for example, an imaging lens such as an interchangeable lens for a single-lens reflex camera, a compact camera, or a video camera, and includes optical elements such as a field lens group, a variator group, a compensator group, and a focus group. The motor control device according to the present embodiment is not limited to the lens position control of an optical apparatus, and can be widely applied to devices that drive a driven body by rotational driving of a motor.

  In this embodiment, the lens 12 is a focus group and performs focus adjustment of the optical device. The motor unit 10 is fixed to a lens barrel (not shown), and the lens frame 11 holds a lens 12 and a lead screw screw 13. The lens frame 11 meshes with the lead screw screw 13, and the lead screw screw 13 rotates to drive the lens frame 11 to advance and retreat along the arrow in the figure. The LP 140 is a position sensor that detects the initial position of the lens 12. The absolute position of the lens is detected based on the number of count pulses obtained from the outputs of the LP 140 and the second position detecting means 107. The lens position control means 141 determines an in-focus state and an out-of-focus state of an image from a signal from an image sensor (not shown) that generates an image. The lens position control unit 141 calculates a target rotation amount based on focus adjustment information (control information) output from the imaging device 150 and inputs the target rotation amount to the rotation amount setting unit 116.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

2 Rotor 6 Output shaft 10 Brushless motor section (motor)
101 First position detecting means (first detecting means)
103 control means 107 second position detection means (second detection means)

Claims (13)

A motor including a rotor in which magnetic poles are formed at certain angles;
First detection means for detecting the rotational position of the rotor;
Second detection means that has a detection resolution higher than the detection resolution of the first detection means and detects the rotational position of the output shaft of the motor;
Control means for controlling drive of the motor using an advance value based on the output signal of the second detection means at the timing when the output signal of the first detection means is outputted. Control device. A measuring unit that measures the number of output signals of the second detection unit at a timing when the output signal of the first detection unit is output;
The motor control apparatus according to claim 1, wherein the control unit controls the advance value based on an output of the measurement unit. A change amount calculation means for calculating a change amount of the speed of the motor based on the output signal of the second detection means;
The control means controls the driving of the motor based on the output signal of the first detection means when the change amount is smaller than a predetermined value, and when the change amount is larger than the predetermined value, the advancement is performed. The motor control device according to claim 1, wherein driving of the motor is controlled using an angular value. A speed deviation calculating means for calculating a speed deviation using the speed of the motor based on the output signal of the second detecting means and the target speed of the motor;
3. The motor control device according to claim 1, wherein when the speed deviation is larger than a predetermined value, the control unit controls driving of the motor based on the speed deviation. A speed deviation calculating means for calculating a first speed deviation using a speed of the motor based on an output signal of the second detecting means and a target speed of the motor;
The control means, when the speed deviation is smaller than a predetermined value, based on the second speed deviation calculated using the motor speed and the target speed based on the output signal of the first detection means. 3. The motor control according to claim 1, wherein the driving of the motor is controlled, and when the speed deviation is larger than the predetermined value, the driving of the motor is controlled based on the first speed deviation. apparatus. A rotation amount deviation calculating means for calculating a rotation amount deviation using the rotation amount of the motor and the target rotation amount;
The motor control apparatus according to claim 1, wherein the control unit controls driving of the motor based on the rotation amount deviation.   The motor control device according to claim 6, wherein the rotation amount deviation is limited by the advance value. A rotation amount deviation calculating means for calculating a rotation amount deviation using the rotation amount of the motor and a target rotation amount;
A speed deviation calculating means for calculating a speed deviation using the motor speed based on the output signal of the second detection means and a target speed of the motor set according to the rotation amount deviation; ,
The motor control apparatus according to claim 1, wherein the control unit controls driving of the motor based on the speed deviation.   3. The motor control device according to claim 1, wherein when the target rotation amount of the motor is smaller than a predetermined value, the control unit switches the control for driving the motor from closed loop control to open loop control. .   The motor control device according to claim 9, wherein the control unit controls the driving of the motor by a minimum driving amount corresponding to the target rotation amount up to the target rotation amount in the open loop control.   The motor control apparatus according to claim 9 or 10, wherein the predetermined value is smaller than an angular resolution of the second detection means.   In the case of restarting the motor control device, the control means has a predetermined number of output signals of the second detection means detected when the motor is driven for a predetermined time under the condition before stopping. When the number is smaller than the number, the driving of the motor is controlled under the condition before the stop, and when larger than the predetermined number, the driving of the motor is controlled based on the output signal of the first detection means. The motor control device according to any one of claims 1 to 11. The motor control device according to any one of claims 1 to 12,
And an optical element driven by the motor control device.