Motor drive control device and control method of motor drive control device

Abstract

The present application provides a motor drive control device and a control method of the motor drive control device, which can reduce the lead wire from the position sensor, and has simple structure, and can determine the rotation direction of the motor. The control circuit part (3) of the motor drive control device (1) has: the first comparator (C1) which compares the size of the first positive Hall signal (H + ) output from the first Hall element (H1) with the size of the first negative Hall signal (H － ) to generate the first position detection signal (S5), the second comparator (C2) which compares the size of the second negative Hall signal (H2 － ) output from the second Hall element (H2) with the size of the first negative Hall signal (H － ) to generate the second position detection signal (S6), and the rotation direction determination part (37) which compares the variation of the first position detection signal (S5) with the variation of the second position detection signal (S6) to determine the rotation direction of the motor (20).

Description

Technical Field

[0001] This invention relates to a motor drive control device and a control method for the motor drive control device. Background Technology

[0002] As a method for determining the rotation direction of a multiphase motor with, for example, three phases, the following methods using induced voltage are known: methods based on the induced voltage generated in the windings when the motor rotates, or methods based on a magnetic sensor and induced voltage, etc.

[0003] Furthermore, Patent Document 1 discloses a control device for a sensorless brushless motor, in which the rotor position is estimated by monitoring the induced voltage, and the energizing phase is switched based on the estimated rotor position. In the case of a position-sensing-free method like Patent Document 1, the rotation direction can be determined by the induced voltage when no power is applied or when energized in an accurate energizing mode. However, when energized, if the energizing mode does not match the rotation direction, it is difficult to perform zero-cross detection, and it is difficult to estimate the rotation direction based on the induced voltage.

[0004] (Prior technical documents)

[0005] (Patent Documents)

[0006] Patent document 1: JP2019-13121A. Summary of the Invention

[0007] (The problem the invention aims to solve)

[0008] If a position sensor is used instead of the method described above that uses induced voltage to determine the direction of rotation, the direction of rotation can be determined even when the energization pattern is disordered. For example, in two position sensors arranged along the direction of rotation of the motor, the direction of rotation can be determined by detecting the change in magnetic flux caused by rotation as an electrical signal.

[0009] As such a position sensor, a Hall element can be used, for example. The electrical signals generated by each Hall element are output as positive and negative signals, and are then output from each Hall element to a control circuit via two leads. The control circuit then generates polarity signals for each of the two Hall elements.

[0010] Thus, in order to use two position sensors to detect the direction of rotation, at least four leads are required to input to the control circuit, which may complicate the configuration of the device.

[0011] The present invention addresses the aforementioned problems. The technical problem of the present invention is to provide a motor drive control device and a control method for the motor drive control device, which can reduce the number of leads from the position sensor, simplify the structure, and at the same time determine the rotation direction of the motor.

[0012] (Technical solution used to solve the problem)

[0013] To address the aforementioned issues, one embodiment of the motor drive control device includes: a motor drive unit that drives a motor; and a control circuit unit that outputs a drive control signal to the motor drive unit. The control circuit unit includes: a first comparison element that generates a first polarity signal by comparing the magnitude of a positive output signal output from a first Hall element with the magnitude of a negative output signal, the first Hall element being disposed at a first position capable of detecting changes in magnetic flux caused by the rotation of the motor; a second comparison element that generates a second polarity signal by comparing the magnitude of a positive or negative output signal output from a second Hall element with the magnitude of a comparison signal being compared, the second Hall element being disposed at a second position capable of detecting changes in magnetic flux caused by the rotation of the motor; and a rotation direction determination unit that determines the rotation direction of the motor by comparing the changes in the first polarity signal with the changes in the second polarity signal.

[0014] (Invention Effects)

[0015] According to the motor drive control device and control method of the present invention, the number of lead wires from the position sensor can be reduced, simplifying the structure, while also enabling the determination of the rotation direction of the motor. Attached Figure Description

[0016] Figure 1 This is a diagram that roughly illustrates the circuit configuration of the motor drive control device 1 according to the first embodiment.

[0017] Figure 2 This is a diagram showing the configuration of two Hall elements in a motor drive control device.

[0018] Figure 3 This is a block diagram showing the configuration of the control circuit section 3 in the first embodiment.

[0019] Figure 4 This is a signal waveform diagram used to illustrate the forward / reverse rotation discrimination method in the first embodiment.

[0020] Figure 5 This is a flowchart illustrating an example of the rotation direction determination process in the first embodiment.

[0021] Figure 6This is a diagram illustrating the first mode of the method for determining forward / reverse rotation.

[0022] Figure 7 This is a diagram illustrating the second mode of the method for determining forward / reverse rotation.

[0023] Figure 8 This is a block diagram showing the configuration of the control circuit section 3 in the second embodiment.

[0024] Figure 9 This is a diagram showing the relationship between the signal waveforms input to the rotational position detection unit in the second embodiment.

[0025] Figure 10 This is a flowchart illustrating an example of the rotation direction determination process in the second embodiment.

[0026] Figure 11 This is a block diagram showing the configuration of the control circuit section 3 in the third embodiment.

[0027] Figure 12 This is a signal waveform diagram used to illustrate the forward / reverse rotation discrimination method in the third embodiment.

[0028] Figure 13 This is a flowchart illustrating an example of the rotation direction determination process in the third embodiment. Detailed Implementation

[0029] 1. Overview of the implementation method

[0030] First, a summary description of representative embodiments of the invention disclosed in this application will be provided. Furthermore, in the following description, as an example, reference numerals corresponding to the components of the invention will be enclosed in parentheses.

[0031] [1] The motor drive control device (1) according to a representative embodiment of the present invention includes: a motor drive unit (2) that drives a motor (20); and a control circuit unit (3) that outputs a drive control signal (Sd) to the motor drive unit (2). The control circuit unit (3) has: a first comparator (C1) that compares the positive output signal (H1) output from the first Hall element (H1) with the positive output signal (H1) from the first Hall element (H1). + The magnitude of the positive or negative output signal (H1-) is compared with the magnitude of the negative output signal (H1-) to generate a first polarity signal (S5). The first Hall element is positioned at a first position capable of detecting changes in magnetic flux caused by the rotation of the motor (20). The second comparator (C2) compares the magnitude of the positive or negative output signal (H2-) from the second Hall element (H2) to generate a first polarity signal (S5). －The magnitude of the first polarity signal (S5) is compared with the magnitude of the comparison signal used as the comparison object to generate a second polarity signal (S6). The second Hall element is disposed at a second position that can detect the change in magnetic flux caused by the rotation of the motor (20). The rotation direction determination unit (37) determines the rotation direction of the motor by comparing the change of the first polarity signal (S5) with the change of the second polarity signal (S6).

[0032] [2] According to the motor drive control device described in [1] above, when the polarity of one of the first polarity signal and the second polarity signal changes, the rotation direction determination unit determines the rotation direction of the motor based on the direction of change of the changing polarity signal and the polarity of the other polarity signal at the time of the change.

[0033] [3] In the motor drive control device described in [2] above, the second comparison element may use the positive output signal or the negative output signal output from the first Hall element as the comparison signal.

[0034] [4] In the motor drive control device described in [2] above, the second comparison element may use a signal of a given reference voltage as the comparison signal.

[0035] [5] According to the motor drive control device described in [3] above, the rotation direction determination unit determines that the motor rotates in the forward direction when the first polarity signal changes from the first polarity to the second polarity and the second polarity signal is the second polarity, and when the first polarity signal changes from the second polarity to the first polarity and the second polarity signal is the first polarity; and when the first polarity signal changes from the first polarity to the second polarity and the second polarity signal is the first polarity, and when the first polarity signal changes from the second polarity to the first polarity and the second polarity signal is the second polarity, the rotation direction determination unit determines that the motor rotates in the reverse direction.

[0036] [6] According to the motor drive control device described in [3] above, the rotation direction determination unit determines that the motor rotates in the forward direction when the first polarity signal changes from the second polarity to the first polarity and the second polarity signal is the first polarity, and when the first polarity signal changes from the first polarity to the second polarity and the second polarity signal is the second polarity; and when the first polarity signal changes from the second polarity to the first polarity and the second polarity signal is the second polarity, and when the first polarity signal changes from the first polarity to the second polarity and the second polarity signal is the first polarity, the rotation direction determination unit determines that the motor rotates in the reverse direction.

[0037] [7] According to the motor drive control device described in [4] above, the first polarity signal is the second polarity when the second polarity signal changes from the second polarity to the first polarity, and the first polarity signal is the first polarity when the second polarity signal changes from the first polarity to the second polarity, in which case the rotation direction determination unit determines that the motor is rotating in the forward direction; and the first polarity signal is the first polarity when the second polarity signal changes from the second polarity to the first polarity, and the first polarity signal is the second polarity when the second polarity signal changes from the first polarity to the second polarity, in which case the rotation direction determination unit determines that the motor is rotating in the reverse direction.

[0038] [8] According to the motor drive control device described in [1] above, the rotation direction determination unit may determine the rotation direction of the motor by the moment when the polarity of the second polarity signal changes during half a cycle of the change of the first polarity signal.

[0039] [9] The control method of the motor drive control device according to the representative embodiment of the present invention controls a motor drive control device including a motor drive unit for driving a motor and a control circuit unit for outputting drive control signals to the motor drive unit. The control method of the motor drive control device includes: a first comparison step, wherein a first polarity signal is generated by comparing the magnitude of a positive output signal output from a first Hall element with the magnitude of a negative output signal, the first Hall element being disposed at a first position capable of detecting changes in magnetic flux caused by the rotation of the motor; a second comparison step, wherein a second polarity signal is generated by comparing the magnitude of a positive output signal or a negative output signal output from a second Hall element with the magnitude of a comparison signal being compared, the second Hall element being disposed at a second position capable of detecting changes in magnetic flux caused by the rotation of the motor; and a rotation direction determination step, wherein the rotation direction of the motor is determined by comparing the changes in the first polarity signal with the changes in the second polarity signal.

[0040] 2. Specific examples of implementation methods

[0041] Hereinafter, specific examples of embodiments of the present invention will be described with reference to the accompanying drawings. Furthermore, in the following description, common components in each embodiment will be given the same reference numerals, and repeated descriptions will be omitted.

[0042] (First Implementation)

[0043] First, the motor drive control device and the control method of the motor drive control device according to the first embodiment will be described.

[0044] Figure 1 This is a diagram that roughly illustrates the circuit configuration of the motor drive control device 1 according to the first embodiment.

[0045] The motor drive control device 1 drives the motor 20. In this embodiment, the motor 20 is, for example, a three-phase brushless motor. The motor drive control device 1 rotates the motor 20 by periodically flowing drive current through the armature coils Lu, Lv, and Lw of the motor 20.

[0046] The motor drive control device 1 includes a motor drive unit 2, a control circuit unit 3, a first Hall element H1, and a second Hall element H2 (H1 and H2 are sometimes simply referred to as Hall elements). Furthermore... Figure 1 The components of the motor drive control device 1 shown are part of a whole; the motor drive control device 1 is in Figure 1 In addition to the components shown, it may have other components.

[0047] In this embodiment, the motor drive control device 1 is an integrated circuit device (IC) in which a portion (e.g., the control circuit section 3 and the pre-drive circuit 2b described later) is packaged. Alternatively, the entire motor drive control device 1 may be packaged as a single integrated circuit device, or all or a portion of the motor drive control device 1 may be packaged together with other devices to form a single integrated circuit device.

[0048] The motor drive unit 2 includes an inverter circuit 2a and a pre-drive circuit 2b. The motor drive unit 2 drives the motor 20 by outputting a drive signal to the motor 20 based on the drive control signal Sd output from the control circuit unit 3.

[0049] The pre-drive circuit 2b, based on the control of the control circuit section 3, generates an output signal for driving the inverter circuit 2a and outputs it to the inverter circuit 2a. The inverter circuit 2a, based on the output signal from the pre-drive circuit 2b, outputs a drive signal to the motor 20 and energizes the armature coils Lu, Lv, and Lw included in the motor 20. The inverter circuit 2a is configured, for example, as a series circuit pair of two switching elements located at both ends of the DC power supply Vcc, respectively arranged relative to each phase (U phase, V phase, W phase) of the armature coils Lu, Lv, and Lw. In each pair of switching elements, the terminals (not shown) of each phase of the motor 20 are connected at the connection points between the switching elements. The pre-drive circuit 2b, based on the drive control signal Sd output from the control circuit section 3 as described later, outputs, for example, six signals Vuu, Vul, Vvu, Vvl, Vwu, and Vwl corresponding to each switching element of the inverter circuit 2a as an output signal. By outputting these output signals, the corresponding switching elements are turned on and off, and drive signals are output to the motor 20 to supply power to each phase of the motor 20 (not shown).

[0050] The speed command signal Sc is input to the control circuit section 3 from an external source, for example. The speed command signal Sc is a signal related to the rotational speed of the motor 20. For example, the speed command signal Sc is a PWM (Pulse Width Modulation) signal corresponding to the target rotational speed of the motor 20. In other words, the speed command signal Sc is information corresponding to the target value of the rotational speed of the motor 20. Alternatively, a clock signal can be input as the speed command signal Sc.

[0051] The first Hall element H1 is disposed at a first position capable of detecting changes in magnetic flux caused by the rotation of the motor 20, and the second Hall element H2 is disposed at a second position capable of detecting changes in magnetic flux caused by the rotation of the motor 20. That is, the first Hall element H1 and the second Hall element H2 are disposed at different positions capable of detecting changes in magnetic flux caused by the rotation of the motor.

[0052] Figure 2 This diagram shows the configuration of the two Hall elements H1 and H2 in the motor drive control device 1 of this embodiment.

[0053] In the motor drive control device 1 of this embodiment, two Hall elements, H1 and H2, are arranged circumferentially separated around the rotor of a motor 20 having six slots. The first Hall element H1 is positioned at any position (first position) capable of detecting changes in magnetic flux caused by the rotation of the motor 20, and the second Hall element H2 is positioned at a mechanical angle of 60 degrees from the first position toward the forward rotation (CW) direction of the motor 20 (second position). Since the motor 20 has six slots, there is an electrical angle of 120 degrees between the first Hall element H1 and the second Hall element H2. The first Hall element H1 detects the magnetic poles of the rotor (not shown) and outputs a first positive Hall signal (an example of a positive output signal) H1. + The first negative Hall signal (an example of a negative output signal) H1 － The second Hall element H2 detects the magnetic poles of the rotor (not shown) and outputs a second negative Hall signal (an example of a negative output signal) H2. － (Hereinafter, H1) + H1 － H2 － Sometimes simply referred to as Hall signal.

[0054] like Figure 1 As shown, in this embodiment, three Hall signals H1 + H1 － H2 － Hall elements H1 and H2, located on motor 20, are input to control circuit section 3. Control circuit section 3 uses Hall signal H1. + H1 － H2 － This yields actual speed information and rotational position information related to the actual speed of the rotor of motor 20.

[0055] The control circuit unit 3 is composed of, for example, a microcomputer, digital circuitry, etc. The control circuit unit 3 is based on a first positive Hall signal H1 input from the first Hall element H1. + First negative Hall signal H1 － The second negative Hall signal H2 input from the second Hall element H2 － The speed command signal Sc input from the outside is used to output the drive control signal Sd to the motor drive unit 2 (pre-drive circuit 2b).

[0056] The control circuit unit 3 controls the rotation of the motor 20 by outputting a drive control signal Sd, causing the motor 20 to rotate at a speed corresponding to the speed command signal Sc. That is, the control circuit unit 3 outputs the drive control signal Sd for driving the motor 20 to the motor drive unit 2 to control the rotation of the motor 20.

[0057] Figure 3This is a block diagram showing the configuration of the control circuit section 3.

[0058] The control circuit section 3 includes, for example, a processor such as a CPU, various memories such as ROM and RAM, timers (counters), A / D conversion circuits, input / output (I / F) circuits, and clock generation circuits, and is composed of a program processing device (e.g., a microcontroller: MCU) whose components are connected to each other via a bus or dedicated line.

[0059] The control circuit unit 3 performs various calculations by a processor according to a program stored in a memory or other storage device (not shown), and controls peripheral circuits such as the A / D conversion circuit and the input / output (I / F) circuit, thereby achieving... Figure 3 The structure of each functional unit is shown. That is, as... Figure 3 As shown, the control circuit unit 3 includes a speed calculation unit 31, a speed command parsing unit 32, a PWM command unit 33, a PWM signal generation unit 35, a rotation position detection unit 36, a rotation direction determination unit 37, and a rotation abnormality detection unit 38 as functional units.

[0060] A Hall signal H1 is input from the first Hall element H1 to the speed calculation unit 31. + H1 － The rotational speed calculation unit 31 calculates the rotational speed based on the input Hall signal H1. + H1 － The output is a position signal indicating the phase relationship between the first Hall element H1 and the rotor. Additionally, the speed calculation unit 31 calculates the speed based on the Hall signal H1. + H1 － The unit generates and outputs actual rotational speed information corresponding to the period of the position signal. That is, the speed calculation unit 31 outputs actual rotational speed information related to the actual rotational speed of the rotor of the motor 20. Figure 3 In this circuit, the actual rotation signal S2 is displayed by combining the position signal and the actual rotation speed information. The actual rotation signal S2 is output to the PWM command unit 33.

[0061] A speed command signal Sc is input to the speed command parsing unit 32. Based on the speed command signal Sc, the speed command parsing unit 32 outputs a target speed signal S1 (hereinafter sometimes simply referred to as target speed S1), representing the target speed of the motor 20. The target speed S1 is a PWM signal representing the duty cycle corresponding to the speed command signal Sc. The target speed S1 is output to the PWM command unit 33.

[0062] The PWM command unit 33 receives the actual rotation signal S2 output from the speed calculation unit 31 and the target speed S1 corresponding to the speed command signal Sc, output from the speed command parsing unit 32. Based on the actual rotation signal S2 (i.e., the position signal), the actual speed information, and the target speed S1, the PWM command unit 33 outputs a PWM setting indication signal S3. The PWM setting indication signal S3 indicates the duty cycle used to output the drive control signal Sd. The PWM setting indication signal S3 is output to the PWM signal generation unit 35.

[0063] The PWM instruction unit 33 compares the target speed S1 with the actual speed information corresponding to the speed of the motor 20, and generates a PWM setting instruction signal S3 in such a way that the rotational speed of the motor 20 corresponds to the target speed S1.

[0064] A PWM setting indication signal S3 is input to the PWM signal generation unit 35. Based on the PWM setting indication signal S3, the PWM signal generation unit 35 generates a PWM signal S4 for driving the motor drive unit 2. The PWM signal S4 is, for example, a signal with the same duty cycle as the PWM setting indication signal S3. In other words, the PWM signal S4 is a signal with a duty cycle corresponding to the PWM setting indication signal S3.

[0065] The PWM signal S4 output from the PWM signal generation unit 35 is output as a drive control signal Sd from the control circuit unit 3 to the motor drive unit 2. As a result, the motor drive unit 2 outputs a drive signal to the motor 20 to drive the motor 20.

[0066] The rotational position detection unit 36 ​​will output Hall signal H1 from the two Hall elements (first Hall element and second Hall element) H1 and H2 disposed on the motor 20. + H1 － H2 － As an input signal, a signal capable of detecting rotational position is generated. Specifically, a first positive Hall signal H1 is input from the first Hall element H1. + First negative Hall signal H1 － and the second negative Hall signal H2 input from the second Hall element H2 － The change in magnetic flux caused by the rotation of motor 20 is shown; therefore, by processing these signals, the rotational position of motor 20 can be detected. In this embodiment, a first position detection signal S5 (an example of a first polarity signal) and a second position detection signal S6 (an example of a second polarity signal) are output as signals capable of detecting rotational position. The first position detection signal S5 is based on a first positive Hall effect signal H1. + The value of the first negative Hall signal H1 －The signal obtained by comparing the values ​​of the first negative Hall signal H1, the second position detection signal S6 is based on the comparison of the values ​​of the first negative Hall signal H1. － The inverted value (an example of a comparison signal used as a comparison object) and the second negative Hall signal H2 － The result is obtained by comparing the values.

[0067] Rotational position detection unit 36, for example Figure 3 As shown, it has two comparators C1 and C2 (an example of a first comparator element and a second comparator element). The rotation position detection unit 36 ​​inputs the Hall signal H1 to the first comparator C1. + H1 － The values ​​are compared, and the comparison output is used as the first position detection signal S5. The rotation position detection unit 36 ​​takes the Hall signal H1 input to the second comparator C2. － H2 － The values ​​are compared, and the comparison output is used as the second position detection signal S6.

[0068] The rotation direction determination unit 37 determines the rotation direction of the motor 20 by comparing the changes in the first position detection signal S5 with the changes in the second position detection signal S6. Specifically, based on the first position detection signal S5 and the second position detection signal S6, which indicate the rotation position and are output from the rotation position detection unit 36, it determines whether the rotation direction of the motor 20 is forward rotation (CW) or reverse rotation (CCW), and outputs the rotation direction determination signal S7 to the rotation abnormality detection unit 38.

[0069] Figure 4 This is a signal waveform diagram used to illustrate the forward / reverse rotation discrimination method in the first embodiment. Figure 4 In the diagram, (a) shows the relationship between the signal waveform input to the rotation position detection unit 36 ​​and the signal waveform output, (b) shows the determination conditions for determining forward rotation (clockwise rotation) and reverse rotation (counter-clockwise rotation) based on the signal waveforms of the first position detection signal S5 and the second position detection signal S6, and (c) shows the determination conditions in more detail.

[0070] like Figure 4 As shown in (a), the first positive Hall signal H1 is compared in the first comparator C1 of the rotation position detection unit 36. + The value of the first negative Hall signal H1 － The value is then used as the value of the first position detection signal S5 and output. In the second comparator C2, it is compared with the first negative Hall signal H1. － The inverted value and the second negative Hall signal H2 －The value is then output as the value of the second position detection signal S6. The rotation direction determination unit 37 is based on... Figure 4 The determination conditions shown in (b) and (c) determine which value of the second position detection signal S6 is being determined at the moment when the first position detection signal S5 changes, thereby determining whether the motor 20 is rotating in the forward direction or in the reverse direction. Figure 4 The signal waveform shown in (a) changes from left to right on the paper when the motor 20 is rotating in the forward direction, and from right to left on the paper when the motor 20 is rotating in the reverse direction.

[0071] Figure 5 This is a flowchart illustrating an example of the rotation direction determination process in the first embodiment.

[0072] The rotation direction determination unit 37 first monitors the value of the first position detection signal S5 and determines whether the value of the first position detection signal S5 has changed (step S101). If it is determined that the value of the first position detection signal S5 has changed (step S101: yes), it determines whether the change is an increase in the signal, that is, the value changes from "0" (an example of the first polarity) to "1" (an example of the second polarity) (step S102). If it is determined that the change in the first position detection signal S5 is an increase (step S102: yes), it determines whether the value of the second position detection signal S6 is H (high) level "1" (step S103).

[0073] If the rotation direction determination unit 37 determines in step S103 that the value of the second position detection signal S6 is H level "1" (step S103: Yes), it determines that the motor 20 is rotating in the forward direction (CW) (step S104). On the other hand, if the rotation direction determination unit 37 determines in step S103 that the value of the second position detection signal S6 is not H level "1" (step S103: No), it determines that the motor 20 is rotating in the reverse direction (CCW) (step S105).

[0074] Similarly, if the rotation direction determination unit 37 determines in step S102 that the change in the value of the first position detection signal S5 is not an increase (i.e., a decrease) (step S102: No), it determines whether the value of the second position detection signal S6 is an L (low) level "0" (step S106). If the rotation direction determination unit 37 determines that the value of the second position detection signal S6 is an L level "0" (step S106: Yes), it determines that the motor 20 is rotating in the forward direction (CW) (step S107). On the other hand, if the rotation direction determination unit 37 determines that the value of the second position detection signal S6 is not an L level "0" (step S106: No), it determines that the motor 20 is rotating in the reverse direction (CCW) (step S108). It should be noted that if the value of the first position detection signal S5 does not change in step S101 (step S101: No), rotation direction determination is not performed, and the process ends.

[0075] The rotation direction determination unit 37 outputs the determination result of forward or reverse rotation as a rotation direction determination signal S7 to the rotation anomaly detection unit 38.

[0076] The discrimination method in the rotation direction discrimination unit 37 can be determined based on different judgment conditions by setting the two comparators C1 and C2 in the rotation position detection unit 36.

[0077] Figure 6 This is a diagram illustrating the first mode of the method for determining forward / reverse rotation. Figure 7 This is a diagram illustrating the second mode of the method for determining forward / reverse rotation. In Figure 6 , 7 In the diagram, (a) shows the relationship between the signal waveform input to the rotation position detection unit 36 ​​and the signal waveform output in each mode, and (b) and (c) show the discrimination conditions for determining forward rotation (clockwise rotation) and reverse rotation (counter-clockwise rotation) based on the signal waveforms of the first position detection signal S5 and the second position detection signal S6.

[0078] The first mode is a diagram representing the discrimination condition for the following situation, namely, that H1 is set in the first comparator C1 so that H1 － >H1 + The first position detection signal S5 becomes L(0) level (low level), and H1 － + The first position detection signal S5 becomes H(1) level (high level). In this case, the second comparator C2 is further set, thus there are mode 1 and mode 2. The second position detection signal S6 of the second comparator C2 is at H1 － >H2 － When it is at level L(0), and at H1​－ <H2 － When it is at the H(1) level, it is Mode 1. On the contrary, the second position detection signal S6 of the second comparator C2 is at the H1 － >H2 － When it is at the H(1) level and at the H1 － <H2 － When it is at the L(0) level, it is Mode 2.

[0079] The second mode is a diagram showing the discrimination condition as follows. That is, in the first comparator C1, it is set so that H1 － >H1 + When the first position detection signal S5 at this time becomes the H(1) level and H1 － <H1 + When the first position detection signal S5 at this time becomes the L(0) level. In this case, further through the setting of the second comparator C2, there are Mode 3 and Mode 4. The second position detection signal S6 of the second comparator C2 is at the H1 － >H2 － When it is at the H(1) level and at the H1 － <H2 － When it is at the L(0) level, it is Mode 3. On the contrary, the second position detection signal S6 of the second comparator C2 is at the H1 － >H2 － When it is at the L(0) level and at the H1 － <H2 － When it is at the H(1) level, it is Mode 4.

[0080] In this way, based on the settings of the two comparators C1 and C2, the discrimination modes are different. The rotation direction discrimination unit 37 determines the values of the first and second position detection signals S5 and S6 based on these modes, thereby being able to discriminate the rotation direction.

[0081] Figure 3 When the rotation abnormality detection unit 38 shown receives the rotation direction discrimination signal S7 indicating the discrimination result of forward rotation or reverse rotation from the rotation direction discrimination unit 37, it determines whether this discrimination result conforms to a rotation abnormality. In the case of determining that there is a rotation abnormality, it outputs the rotation abnormality detection signal S8 to the PWM command unit 33. When the PWM command unit 33 receives the rotation abnormality detection signal S8, for example, it can issue an instruction to stop the generation of the PWM signal to the PWM signal generation unit 35 as needed.

[0082] In this way, according to the motor drive control device and the control method of the motor drive control device of the present embodiment, it is possible to reduce the lead wires drawn from the position sensor, and the structure is simple, and at the same time, it is possible to discriminate the rotation direction of the motor.

[0083] (Second Implementation)

[0084] Next, the motor drive control device and the control method of the motor drive control device according to the second embodiment will be described.

[0085] Figure 8 This is a block diagram showing the configuration of the control circuit section 3A in the second embodiment.

[0086] In the motor drive control device 1 of the first embodiment, a Hall signal H1 is input to the rotational position detection unit 36. + H1 － H2 － However, in the motor drive control device 1A of this embodiment, the difference is as follows: Figure 8 As shown, in the rotational position detection unit 36, in addition to the input Hall signal H1 + H1 － H2 － In addition, a reference voltage with a specified potential is input (for example, a comparison signal used as a comparison object). Furthermore, the difference lies in that the rotation direction determination unit 37A compares the changes in the first position detection signal S5 and the second position detection signal S6 corresponding to these inputs according to a determination criterion different from that of the first embodiment, thereby determining the rotation direction of the motor. Regarding other configurations, they are the same as those of the motor drive control device 1 and its control method in the first embodiment, therefore their description is omitted.

[0087] Figure 9 This is a diagram showing the relationship between the signal waveforms input to the rotational position detection unit 36A in the second embodiment. Figure 9 In the diagram, (a) is the input signal waveform when rotating in the forward direction, and (b) is the input signal waveform when rotating in the reverse direction.

[0088] Figure 10 This is a flowchart illustrating an example of the rotation direction determination process in the second embodiment.

[0089] Furthermore, in this embodiment, the following settings are made in the first comparator C1: H1 － >H1 + The first position detection signal S5 becomes level H(1), H1 － + The first position detection signal S5 becomes L(0) level. Similarly, in the second comparator C2, it is set such that: H2 － When the second position detection signal S6 is greater than (reference voltage), it becomes level H(1), and H2 becomes level H2. － ​When the voltage is less than (reference voltage), the second position detection signal S6 becomes the L(0) level.

[0090] Firstly, regarding Figure 9 The rotation direction determination operation performed by the rotation direction determination unit 37A at time point T1 (a) will be explained. The rotation direction determination unit 37A first determines whether the second position detection signal S6 has been interrupted (step S201). Here, interruption means a change in the value of the second position detection signal S6. The rotation direction determination unit 37A determines at time point T1 that an interruption has occurred (step S201: Yes), and then determines whether an increase has occurred due to the interruption (step S202). Here, at time point T1, the second position detection signal S6 changes from "0" to "1", therefore the rotation direction determination unit 37A determines that an increase has occurred (step S202: Yes), and determines whether the value of the first position detection signal S5 indicates H1. + >H1 － (Step S203). At time point T1, the value of the first position detection signal S5 is not shown as H1. + >H1 － In the case of (step S203: no), the rotation direction determination unit 37A determines that it is rotating in the forward direction (CW) (step S205).

[0091] In addition, Figure 9 Similarly, at time point T4 (b), the rotation direction determination unit 37A makes the same determination as at time point T1 up to step S203. In step S203, the value of the first position detection signal S5 at time point T4 indicates H1. + >H1 － In the case of (step S203: yes), it is determined that it is in reverse rotation (CCW) (step S204).

[0092] against Figure 9 The rotation direction determination operation performed by the rotation direction determination unit 37A at time point T3 (b) will be explained. The rotation direction determination unit 37A first determines at time point T3 that the second position detection signal S6 has been interrupted (step S201: Yes), and then determines whether an increase has occurred due to the interruption (step S202). Here, at time point T3, the second position detection signal S6 changes from "1" to "0", therefore the rotation direction determination unit 37A determines that no increase has occurred (step S202: No), and determines whether the value of the first position detection signal S5 indicates H1. + － (Step S206). At time point T3, the value of the first position detection signal S5 indicates H1. + － ​​In the case of (step S206: Yes), the rotation direction determination unit 37A determines that it is in reverse rotation (CCW) (step S208).

[0093] In addition, Figure 9 Similarly, at time point T2 (a), the rotation direction determination unit 37A makes the same determination as at time point T3 up to step S206. However, in step S206, the value of the first position detection signal S5 at time point T2 is not shown (H1). + － In the case of (step S206: yes), it is determined that it is in the forward rotation (CW) (step S207).

[0094] Even the motor drive control device 1A and the control method of the motor drive control device 1A in the second embodiment can, like the first embodiment, reduce the number of leads from the position sensor, have a simple structure, and be able to determine the rotation direction of the motor.

[0095] (Third Implementation)

[0096] Next, the motor drive control device and the control method of the motor drive control device according to the third embodiment will be described.

[0097] Figure 11 This is a block diagram showing the configuration of the control circuit section 3B in the third embodiment.

[0098] In the motor drive control devices 1 and 1A described above, when the output of either the first position detection signal S5 or the second position detection signal S6 received by the rotation direction determination unit 37 and 37A from the rotation position detection unit 36 ​​changes, the rotation direction of the motor is determined based on the direction of the change (whether it changes from "0" to "1" or from "1" to "0") and a comparison with the output of the other position detection signal S5 or S6 at the time of the change (whether it is "0" or "1"). In the motor drive control device 1B of this embodiment, the rotation direction determination unit 37B compares the change in the first position detection signal S5 with the change in the second position detection signal S6 according to a different determination criterion than in the first and second embodiments. The rotation direction determination unit 37B is configured to determine the rotation direction of the motor by the moment when the change in the output of the second position detection signal S6 occurs within half a cycle of the change in the first position detection signal S5. Regarding other components, they are the same as those of the motor drive control device 1 and the control method of the motor drive control device 1 in the first embodiment, so their description is omitted.

[0099] Figure 12 This is a diagram showing the relationship of the signal waveforms input to the rotational position detection unit 36.​ Figure 12 In the diagram, (a) is the input signal waveform when rotating in the reverse direction, and (b) is the input signal waveform when rotating in the forward direction.

[0100] Figure 13 This is a flowchart illustrating an example of the rotation direction determination process in the third embodiment.

[0101] Furthermore, in this embodiment, the first comparator C1 is configured such that: H1 － >H1 + The first position detection signal S5 becomes H(1) level, and H1 － + The first position detection signal S5 becomes L(0) level. Similarly, in the second comparator C2, it is set such that: H2 － >H1 － When the comparison output S6 becomes level H(1), and H2 － － The comparison output S6 becomes the L(0) level.

[0102] Firstly, regarding Figure 12 The rotation direction determination operation performed by the rotation direction determination unit 37B at the time point T5 of the reverse rotation in (a) will be explained. The rotation direction determination unit 37B uses timer 39. First, it measures the time of half a cycle of the first position detection signal S5, that is, the time it takes for the value of the first position detection signal S5 to change (the time it takes for the electrical angle to move 180 degrees) (step S301). The rotation direction determination unit 37B saves the half-cycle time measured in step S301.

[0103] The rotation direction determination unit 37B uses timer 39 to measure the time from the point when the first position detection signal S5 changes (power-on switching moment) to the point when the second position detection signal S6 changes (T5(H2)). － H1 － The elapsed time up to the switching time (step S302) is measured, and it is determined whether the measured elapsed time up to time point T5 is less than 1 / 3 of the half-cycle time (time for 180 electrical degrees) saved in step S301 (an example of a judgment condition) (step S303). Figure 12 In the example shown in (a), the time from the time point of change of the first position detection signal S5 to the time point T5 is less than 1 / 3 of the half cycle (step S303: Yes), so it is determined that the motor is rotating in the reverse direction (CCW) (step S304).

[0104] Next, regarding Figure 12 ​​The rotation direction determination operation performed by the rotation direction determination unit 37B at the time point T6 of the forward rotation of (b) will be explained. Steps S301 and S302 are performed in the same manner as described above.

[0105] The rotation direction determination unit 37B uses timer 39 to measure the time from the point when the first position detection signal S5 changes (power-on switching moment) to the point when the second position detection signal S6 changes (T6(H2)). － H1 － The elapsed time up to the switching time (step S302) is measured, and it is determined whether the measured elapsed time up to time point T6 is less than 1 / 3 of the half-cycle time (time for 180 electrical degrees) saved in step S301 (an example of a judgment condition) (step S303). Figure 12 In the example shown in (a), the time from the moment the first position detection signal S5 changes to time point T6 is not less than 1 / 3 of the half-cycle (step S303: No). Therefore, it is further determined whether the time from the moment the first position detection signal S5 changes to time point T6 is more than 2 / 3 of the half-cycle (step S305). Since the time from the moment the first position detection signal S5 changes to time point T6 is more than 2 / 3 of the half-cycle (step S305: Yes), the rotation direction determination unit 37B can determine that it is rotating in the forward direction (CW) (step S306).

[0106] Even the motor drive control device and control method of the third embodiment can, like other embodiments, reduce the number of leads from the position sensor, have a simple structure, and can determine the rotation direction of the motor.

[0107] (Modifications of the implementation method)

[0108] In the above embodiments, the configuration of the motor drive control device is not limited to... Figure 1 The configuration of the two Hall elements in the motor drive control device is not limited to... Figure 2 The configuration is as follows. For example, although a 3-phase brushless motor was described as an example in the above embodiment, the type of motor and the number of phases are not particularly limited. In addition, for example, although the position of the two Hall elements is not particularly limited, the waveforms of the first position detection signal S5 and the second position detection signal S6 can be determined based on the configuration conditions of the Hall elements.

[0109] The configuration of the control circuit section is not limited to Figure 3 , 8 The composition of 11.

[0110] In the above implementation methods Figure 5 , 10 The processing flow shown in Figure 13 is a specific example, and the processing flow is not limited to this. For example, different judgment processes can be performed according to the judgment conditions. In this case, the judgment conditions of the second and third embodiments are the same as those of the first embodiment. By changing the settings of the first comparator C1 and the second comparator C2, different judgment conditions can be used. In addition, as the judgment condition of the third embodiment, the judgment condition corresponding to the configuration conditions of the two Hall elements can be set as the judgment condition, instead of the judgment of less than 1 / 3 of the half-cycle time or the judgment of more than 2 / 3 of the half-cycle time.

[0111] Label Explanation

[0112] 1. 1A, 1B Motor drive control device; 2. Motor drive unit; 2a Inverter circuit; 2b Pre-drive circuit; 20 Motor; 3. 3A, 3B Control circuit unit; 31 Speed ​​calculation unit; 32 Speed ​​command parsing unit; 33 PWM command unit; 35 PWM signal generation unit; 36 Rotation position detection unit; 37, 37A, 37B Rotation direction discrimination unit; 38 Rotation anomaly detection unit; Sd Drive control signal; Sc Speed ​​command signal; S1 Target speed (target speed signal); S2 Actual speed signal; S3 PWM setting indication signal; S4 PWM signal; S5 First position detection signal (an example of a first polarity signal); S6 Second position detection signal (an example of a second polarity signal); S7 Rotation direction discrimination signal; S8 Rotation anomaly detection signal; H1 First Hall element; H2 Second Hall element; H1 + The first positive Hall signal (an example of a positive output signal), H1 － The first negative Hall signal (an example of a negative output signal), H2 － Second negative Hall signal (an example of a negative output signal), C1 first comparator (an example of a first comparator element), C2 second comparator (an example of a second comparator element), Lu, Lv, Lw armature coils, Vcc DC power supply.

Claims

1. A motor drive control device, characterized in that, include: The motor drive unit, which drives the motor; as well as The control circuit section outputs drive control signals to the motor drive section. The control circuit section includes: The first comparator generates a first polarity signal by comparing the magnitude of a positive output signal output from a first Hall element with the magnitude of a negative output signal. The first Hall element is disposed at a first position capable of detecting changes in magnetic flux caused by the rotation of the motor. The second comparator generates a second polarity signal by comparing the magnitude of a positive or negative output signal from the second Hall element with the magnitude of a comparison signal used as the comparison object. The second Hall element is positioned at a second position capable of detecting changes in magnetic flux caused by the rotation of the motor. The rotation direction determination unit determines the rotation direction of the motor by comparing the changes in the first polarity signal with the changes in the second polarity signal. When the polarity of one of the first polarity signals and the second polarity signal changes, the rotation direction determination unit determines the rotation direction of the motor based on the direction of change of the polarity signal and the polarity of the other polarity signal at the time of the change. The second comparator uses the positive output signal or the negative output signal output from the first Hall element, or a signal of a given reference voltage, as the comparison signal.

2. The motor drive control device according to claim 1, wherein, The comparison signal is either the positive output signal or the negative output signal output from the first Hall element. The rotation direction determination unit determines that the motor is rotating in the forward direction under the following conditions: when the first polarity signal changes from the first polarity to the second polarity, the second polarity signal is the second polarity; and when the first polarity signal changes from the second polarity to the first polarity, the second polarity signal is the first polarity. The rotation direction determination unit determines that the motor is rotating in the opposite direction under the following conditions: when the first polarity signal changes from the first polarity to the second polarity, the second polarity signal is the first polarity; and when the first polarity signal changes from the second polarity to the first polarity, the second polarity signal is the second polarity.

3. The motor drive control device according to claim 1, wherein, The comparison signal is either the positive output signal or the negative output signal output from the first Hall element. The rotation direction determination unit determines that the motor is rotating in the forward direction under the following conditions: when the first polarity signal changes from the second polarity to the first polarity, the second polarity signal is the first polarity; and when the first polarity signal changes from the first polarity to the second polarity, the second polarity signal is the second polarity. The rotation direction determination unit determines that the motor is rotating in the opposite direction under the following conditions: when the first polarity signal changes from the second polarity to the first polarity, the second polarity signal is the second polarity, and when the first polarity signal changes from the first polarity to the second polarity, the second polarity signal is the first polarity.

4. The motor drive control device according to claim 1, wherein, The comparison signal is a signal of a given reference voltage. The rotation direction determination unit determines that the motor is rotating in the forward direction under the following conditions: when the second polarity signal changes from the second polarity to the first polarity, the first polarity signal is the second polarity; and when the second polarity signal changes from the first polarity to the second polarity, the first polarity signal is the first polarity. The rotation direction determination unit determines that the motor is rotating in the opposite direction under the following conditions: when the second polarity signal changes from the second polarity to the first polarity, the first polarity signal is the first polarity; and when the second polarity signal changes from the first polarity to the second polarity, the first polarity signal is the second polarity.

5. The motor drive control device according to claim 1, wherein, The rotation direction determination unit determines the rotation direction of the motor by the moment when the polarity of the second polarity signal changes within half a cycle of the change of the first polarity signal.

6. A control method for a motor drive control device, the motor drive control device comprising: The motor drive unit, which drives the motor; And a control circuit section, which outputs drive control signals to the motor drive section. The control method of the motor drive control device is characterized by including: In the first comparison step, a first polarity signal is generated by comparing the magnitude of a positive output signal output from a first Hall element with the magnitude of a negative output signal. The first Hall element is disposed at a first position capable of detecting changes in magnetic flux caused by the rotation of the motor. The second comparison step involves generating a second polarity signal by comparing the magnitude of a positive or negative output signal from the second Hall element with the magnitude of a comparison signal used as the comparison object. The second Hall element is positioned at a second position capable of detecting changes in magnetic flux caused by the rotation of the motor. The rotation direction determination step involves comparing the changes in the first polarity signal with the changes in the second polarity signal to determine the rotation direction of the motor. When the polarity of one of the first polarity signals and the second polarity signal changes, the rotation direction determination step determines the rotation direction of the motor based on the direction of change of the changing polarity signal and the polarity of the other polarity signal at the time of the change. The second comparison step uses the positive output signal or the negative output signal output from the first Hall element, or a signal of a given reference voltage, as the comparison signal.

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