Motor drive control device, motor unit, and motor drive control method

Abstract

To achieve both reduction in starting time and improved vibration after starting.SOLUTION: A motor drive controller 10 comprises a control circuit part 3 that switches electrification patterns of three-phase coils Lu, Lv, Lw electrified with a motor drive part 2 in a predetermined order by outputting a drive control signal Sd to the motor drive part 2 for selectively electrifying the three-phase coils Lu, Lv, Lw of a motor 20. The control circuit part 3 has: an electrification switching signal production part 35 that produces an electrification switching signal S6 for switching the electrification patterns to the three-phase coils Lu, Lv, Lw of the motor 20 in timing determined with either a 180 degree section or a 360 degree section of a positional detection signal Shu as a reference according to a rotation state of the motor 20; and a drive control signal production part 33 that produces a PWM signal S4 for performing sine wave driving of the motor 20 as the drive control signal Sd by switching the electrification patterns based on the electrification switching signal S6.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a motor drive control device, a motor unit, and a motor drive control method.

Background Art

[0002] In the sine wave drive of a motor, for every 360 electrical degrees, a drive signal (PWM signal) with a predetermined duty ratio for each PWM period is generated, and the switching element is turned on and off to control the coil current of the motor to have a sine wave waveform.

[0003] The generation timing of the drive signal with a predetermined duty ratio for every 360 electrical degrees is determined from the change time of the position detection signal immediately before being output from a position detector that detects the position of the rotor of the motor. The change of the position detection signal is every 60 electrical degrees when there are three position detectors, while it is every 180 electrical degrees or every 360 electrical degrees when there is one position detector. Therefore, that section is measured to calculate 60 electrical degrees and realize sine wave drive.

[0004] Conventionally, a motor drive circuit that uses one hall element as a position detector and performs energization phase switching of the motor at the timing obtained for each period of electrical angle 180 degrees / n or electrical angle 360 degrees / n of the hall signal output by the hall element is known (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0005] [[ID=3U]]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the motor drive circuit described in Patent Document 1, there is no specific mention of whether the timing for switching the motor's energized phase is determined (or utilized) based on the 180-degree electrical angle interval or the 360-degree electrical angle interval of the Hall signal.

[0007] In their investigation into the switching of the energized phase of a motor, the inventors found the following differences between determining a 60-degree electrical angle based on a 180-degree electrical angle interval and determining a 60-degree electrical angle based on a 360-degree electrical angle interval.

[0008] In other words, when using a 180-degree interval, the rotational speed of the motor immediately before (change in the position detection signal) can be reflected in the power supply, resulting in higher tracking performance compared to using a 360-degree interval. However, if the duty cycle of the Hall signal varies, the timing of switching the power supply pattern will be off, and in that case, the power supply will become more unstable compared to when using a 360-degree interval, increasing the likelihood of vibration.

[0009] On the other hand, when using a 360-degree interval, even if the duty cycle of the position detection signal varies, it can be averaged to calculate 60 degrees, so the timing of switching the power supply pattern is stable, and the possibility of vibration is lower compared to when using a 180-degree interval. However, because the rotation speed of the motor immediately before (change in the position detection signal) is averaged, the tracking performance is lower compared to when using a 180-degree interval.

[0010] In light of the differences described above, we discovered that by switching the motor's energization pattern based on an electrical angle of 60 degrees determined by an appropriate method, it is possible to achieve both a reduction in startup time and improvement in vibration after startup, leading to the present invention.

[0011] The present invention aims to solve the above-mentioned problems and to provide a motor drive control device, motor unit, and motor drive control method that can achieve both a reduction in startup time and improvement of vibration after startup. [Means for solving the problem]

[0012] A motor drive control device according to a typical embodiment of the present invention comprises: a motor drive unit that selectively energizes multiple phase coils of a motor; a control circuit unit that outputs a drive control signal to the motor drive unit, thereby switching the energization pattern of the multiple phase coils energized by the motor drive unit in a predetermined order; and a position detection signal output unit that outputs a position detection signal corresponding to the position of the motor rotor. The control circuit unit is characterized by comprising: an energization switching signal generation unit that generates an energization switching signal for switching the energization pattern to the multiple phase coils of the motor at a timing determined based on either a 180-degree interval or a 360-degree interval in the position detection signal, depending on the rotation state of the motor; and a drive control signal generation unit that generates a control signal for driving the motor sinusoidally by switching the energization pattern based on the energization switching signal. [Effects of the Invention]

[0013] According to one aspect of the present invention, it is possible to achieve both a reduction in startup time and improvement of vibration after startup. [Brief explanation of the drawing]

[0014] [Figure 1] This figure shows the configuration of a motor unit 1 equipped with a motor drive control device 10 according to this embodiment. [Figure 2] This figure shows an example of a drive signal in a 120-degree energized square wave drive. [Figure 3] This figure shows an example of a drive signal in sinusoidal drive. [Figure 4] This figure shows an example of the drive signal and winding current waveform for the U phase in sinusoidal drive. [Figure 5] This figure shows an example of the control operation in the motor drive control device 10 according to this embodiment. [Figure 6] This diagram illustrates the relationship between the position detection signal Shu and the power switching signal S6. [Figure 7] This figure shows an example of the processing flow for power supply control in the control circuit unit 3. [Modes for carrying out the invention]

[0015] 1. Overview of the Embodiment First, a general overview of a typical embodiment of the invention disclosed in this application will be provided. In the following description, as an example, reference numerals on the drawings corresponding to the components of the invention are indicated in parentheses.

[0016] [1] A motor drive control device (10) according to a typical embodiment of the present invention comprises: a motor drive unit (2) that selectively energizes multiple phase coils (Lu, Lv, Lw) of a motor (20); a control circuit unit (3) that outputs a drive control signal (Sd) to the motor drive unit, thereby switching the energization pattern of the multiple phase coils energized by the motor drive unit in a predetermined order; and a position detection signal output unit (25) that outputs a position detection signal (Shu) corresponding to the position of the rotor of the motor, wherein the control circuit unit comprises: an energization switching signal generation unit (35) that generates an energization switching signal (S6) for switching the energization pattern to the multiple phase coils of the motor at a timing determined based on either a 180-degree interval or a 360-degree interval in the position detection signal according to the rotation state of the motor; and a drive control signal generation unit (33) that generates a drive control signal as the drive control signal, which switches the energization pattern based on the energization switching signal and drives the motor in a sinusoidal manner.

[0017] 〔2〕In the motor drive control device according to 〔1〕 above, the energization switching signal generation unit may include a synchronization determination unit that determines whether the change timing of the position detection signal and the switching timing of the energization switching signal are synchronized, and when it is determined in the synchronization determination unit that the change timing of the position detection signal and the switching timing of the energization switching signal are not synchronized, the energization switching signal is generated at a timing determined based on the 180-degree interval, and when it is determined in the synchronization determination unit that the change timing of the position detection signal and the switching timing of the energization switching signal are synchronized, a signal generation unit that generates the energization switching signal at a timing determined based on the 360-degree interval.

[0018] 〔3〕In the motor drive control device according to 〔2〕 above, before detecting the position detection signal when the motor is started, the control circuit unit gives an instruction to the drive control signal generation unit to generate a control signal for driving the motor in a rectangular wave as the drive control signal, and after detecting the position detection signal when the motor is started, the control circuit unit may further include an energization method instruction unit that gives an instruction to the drive control signal generation unit to generate a control signal for driving the motor in a sine wave as the drive control signal.

[0019] 〔4〕In the motor drive control device according to 〔3〕 above, when the drive control signal generation unit receives an instruction from the energization method instruction unit to generate a control signal for driving the motor in a rectangular wave, the drive control signal generation unit may generate a control signal for performing 120-degree energization as the drive control signal.

[0020] 〔5〕A motor unit (1) according to a typical embodiment of the present invention is characterized by including the motor drive control device (10) according to any one of 〔1〕 to 〔4〕 above and the motor (20).

[0021] [6] A motor drive control method according to a typical embodiment of the present invention is a motor drive control method using a motor drive control device comprising: a motor drive unit that selectively energizes multiple phase coils of a motor; a control circuit unit that outputs a drive control signal to the motor drive unit, thereby switching the energization pattern of the multiple phase coils energized by the motor drive unit in a predetermined order; and a position detector that outputs a position detection signal corresponding to the position of the rotor of the motor, characterized in that the control circuit unit generates an energization switching signal for switching the energization pattern to the multiple phase coils of the motor at a timing determined based on either a 180-degree interval or a 360-degree interval in the position detection signal, depending on the rotation state of the motor; and generates a control signal as the drive control signal for switching the energization pattern based on the energization switching signal and driving the motor in a sinusoidal manner.

[0022] 2. Specific Examples of Embodiments Hereinafter, specific examples of embodiments of the present invention will be described with reference to the figures. In the following description, common components in each embodiment will be denoted by the same reference numerals, and repeated descriptions will be omitted.

[0023] <Embodiment> Figure 1 shows the configuration of a motor unit 1 equipped with a motor drive control device 10 according to this embodiment.

[0024] The motor unit 1 shown in Figure 1 comprises a motor drive control device 10, a motor 20, and a position detector (an example of a position detection signal output unit) 25.

[0025] Motor 20 is a motor having at least one coil. In this embodiment, for example, motor 20 is a brushless DC motor having three phases (U phase, V phase, and W phase) coils (windings) Lu, Lv, Lw. Motor 20 functions as a fan motor by, for example, connecting an impeller (not shown) to the output shaft of motor 20.

[0026] The position detector 25 is a device that generates a position detection signal Shu in accordance with the rotation of the rotor of the motor 20. The position detector 25 is, for example, a Hall IC. In the motor unit 1 according to this embodiment, the Hall IC is provided at a position corresponding to the U-phase coil Lu of the motor 20. The Hall IC detects the magnetic poles of the rotor and converts the signal, whose voltage changes according to the rotation of the rotor, into a signal that periodically becomes high and low, and outputs it as a Hall signal. The Hall signal output from the position detector 25 is input to the motor drive control device 10 as the position detection signal Shu.

[0027] The motor drive control device 10 is a device that controls the driving of the motor 20. The motor drive control device 10 drives the motor 20 by, for example, performing control to generate a drive signal such that the rotational speed of the motor 20 matches the target rotational speed and a rectangular wave or sinusoidal wave current flows through the coils Lu, Lv, Lw of each phase of the motor 20.

[0028] The motor drive control device 10 comprises a control circuit unit 3 and a motor drive unit 2. The motor drive control device 10 receives a DC voltage from an external DC power supply (not shown). The DC voltage is supplied to a power line (not shown) within the motor drive control device 10, for example, via a protection circuit, and is input as a power supply voltage to the control circuit unit 3 and the motor drive unit 2, respectively, via the power line.

[0029] The motor drive unit 2 includes an inverter circuit 2a and a pre-drive circuit 2b. The inverter circuit 2a has, for example, six switching elements (not shown) and supplies AC power to the three-phase coils Lu, Lv, and Lw of the motor 20. Three of the six switching elements are high-side switching elements located on the positive side of the power supply Vcc, and the remaining three low-side switching elements are located on the negative side of the power supply Vcc.

[0030] The pre-drive circuit 2b has six output terminals connected to the gate terminals of each of the six switching elements of the inverter circuit 2a. Based on the drive control signal Sd output from the control circuit unit 3, the pre-drive circuit 2b outputs drive signals Vuh, Vul, Vvh, Vvl, Vwh, and Vwl for each of the six switching elements of the inverter circuit 2a, controlling the on / off operation of the switching elements. The drive signals Vuh, Vul, Vvh, Vvl, Vwh, and Vwl are the U-phase high-side drive signal, U-phase low-side drive signal, V-phase high-side drive signal, V-phase low-side drive signal, W-phase high-side drive signal, and W-phase low-side drive signal, respectively.

[0031] The motor drive unit 2 is a circuit that drives the motor 20 based on the drive control signal Sd output from the control circuit unit 3. The drive control signal Sd is a signal for controlling the drive of the motor 20, and is, for example, a PWM signal.

[0032] The control circuit unit 3 is a circuit for comprehensively controlling the operation of the motor drive control device 10. In this embodiment, the control circuit unit 3 is a program processing device having a configuration in which a processor such as a CPU, various storage devices such as RAM, ROM, and flash memory, and peripheral circuits such as a counter (timer), A / D conversion circuit, D / A conversion circuit, clock generation circuit, and input / output interface circuit are connected to each other via a bus or dedicated line. For example, the control circuit unit 3 is a microcontroller (MCU: Micro Controller Unit).

[0033] The control circuit unit 3 and the motor drive unit 2 may be packaged as a single semiconductor integrated circuit (IC), or they may be packaged as separate integrated circuits, mounted on a circuit board, and electrically connected to each other on the circuit board.

[0034] The control circuit unit 3 performs PWM control. Specifically, the control circuit unit 3 generates a PWM signal (an example of a control signal) S4 with a duty cycle determined so that the rotational speed of the motor 20 matches the target rotational speed and a rectangular wave or sinusoidal wave current flows through the coils Lu, Lv, Lw of each phase of the motor 20, and outputs it as a drive control signal Sd.

[0035] Here, we will explain the method for generating the PWM signal S4 in the control circuit unit 3. In the motor drive control device 10 of this embodiment, the control circuit unit 3 generates a PWM signal S4 using different generation methods depending on the rotation state of the motor 20, thereby enabling both a reduction in startup time and improvement of vibration after startup.

[0036] The control circuit unit 3 generates a PWM signal S4 that causes the current flowing through the coils Lu, Lv, and Lw of each phase of the motor 20 to be square wave (performs square wave driving) until it detects the position detection signal Shu during startup. After detecting the position detection signal Shu during startup, it generates a PWM signal S4 that causes the current flowing through the coils Lu, Lv, and Lw of each phase of the motor 20 to be sinusoidal (performs sinusoidal driving).

[0037] Here, "the position detection signal Shu was detected at startup" means that the position detection signal Shu was detected over a period of time sufficient to determine the rotational position of the motor 20 based on the position detection signal Shu. For example, if the position detection signal Shu is detected over a period of 180 degrees, it can be determined that the motor 20 has rotated half a turn, and therefore it can be determined that "the position detection signal Shu was detected at startup." In other words, at startup, until the position detection signal Shu over a period of 180 degrees is detected, the control circuit unit 3 generates a PWM signal S4 so that a rectangular wave current flows through the coils Lu, Lv, and Lw of each phase of the motor 20, and performs rectangular wave driving by outputting it as a drive control signal Sd.

[0038] Figure 2 shows an example of a drive signal in a 120-degree energized square wave drive. Figure 2 shows the waveforms of the drive signals (on / off signals) input to each switching element of the inverter circuit 2a in a 120-degree energized square wave drive. Specifically, from top to bottom in Figure 2, the waveforms of the position detection signal Shu, the U-phase high-side drive signal Vuh, the U-phase low-side drive signal Vul, the V-phase high-side drive signal Vvh, the V-phase low-side drive signal Vvl, the W-phase high-side drive signal Vwh, and the W-phase low-side drive signal Vwl are shown.

[0039] Figure 2 also shows that the energizing patterns for the three-phase coils Lu, Lv, and Lw are switched every 60 degrees in the order of VU, WU, WV, UV, UW, and VW. Note that energizing pattern VU is an energizing pattern in which the winding current flows from the V-phase coil Lv to the U-phase coil Lu; energizing pattern WU is an energizing pattern in which the winding current flows from the W-phase coil Lw to the U-phase coil Lu; energizing pattern WV is an energizing pattern in which the winding current flows from the W-phase coil Lw to the V-phase coil Lv; energizing pattern UV is an energizing pattern in which the winding current flows from the U-phase coil Lu to the V-phase coil Lv; energizing pattern UW is an energizing pattern in which the winding current flows from the U-phase coil Lu to the W-phase coil Lw; and energizing pattern VW is an energizing pattern in which the winding current flows from the V-phase coil Lv to the W-phase coil Lw. In the example shown in Figure 2, the energization pattern to the three-phase coils Lu, Lv, and Lw of the motor 20 is controlled to switch in a predetermined order (in this example, in the order VU, WU, WV, UV, UW, and VW) by controlling the drive signals Vuh, Vul, Vvh, Vvl, Vwl, Vwl every 60 degrees of electrical angle. The energization pattern is switched based on the energization switching signal S6 for switching the energization pattern of the three-phase coils Lu, Lv, and Lw of the motor 20.

[0040] In square wave driving, as shown in Figure 2, the control circuit unit 3 controls the drive signals Vuh, Vul, Vvh, Vvl, Vwh, and Vwl input to each switching element of the inverter circuit 2a to selectively energize the three-phase coils Lu, Lv, and Lw, thereby switching the energized phase every 60 degrees of electrical angle. The switching timing of the energization switching signal S6 in square wave driving is set to a predetermined 60-degree electrical angle timing by a timer inside the control circuit unit 3.

[0041] On the other hand, at startup, the control circuit unit 3, for example, after detecting a position detection signal Shu for a 180-degree section, generates a PWM signal S4 so that a sinusoidal current flows through the coils Lu, Lv, and Lw of each phase of the motor 20, and performs sinusoidal drive by outputting it as a drive control signal Sd.

[0042] Figure 3 shows an example of a drive signal in sinusoidal drive. Figure 3 shows the waveforms of the drive signals (PWM signals) input to each switching element of the inverter circuit 2a in sinusoidal drive. Specifically, from top to bottom in Figure 3, the waveforms of the position detection signal Shu, the U-phase high-side drive signal Vuh, the U-phase low-side drive signal Vul, the V-phase high-side drive signal Vvh, the V-phase low-side drive signal Vvl, the W-phase high-side drive signal Vwh, and the W-phase low-side drive signal Vwl are shown.

[0043] Figure 4 shows an example of the drive signal and winding current waveform for the U phase in sinusoidal drive. Figure 4 shows the waveforms of the drive signal (PWM signal) input to the U-phase switching element and the winding current flowing through the U-phase coil Lu in a sinusoidal drive. Specifically, from top to bottom in Figure 4, the waveforms of the position detection signal Shu, the U-phase high-side drive signal Vuh, the U-phase low-side drive signal Vul, and the winding current flowing through the U-phase coil Lu are shown.

[0044] As shown in Figure 4, in the control circuit section 3, a sinusoidal winding current flows through the U-phase coil Lu in response to the U-phase high-side drive signal Vuh and the U-phase low-side drive signal Vul.

[0045] In sinusoidal drive, the control circuit unit 3 generates a PWM signal S4 such that sinusoidal winding currents with a phase difference of 120 degrees flow through the U-phase, V-phase, and W-phase coils Lu, Lv, and Lw of the motor 20, and provides this as a drive control signal Sd to the motor drive unit 2. The drive signals (PWM signals) input to each switching element of the inverter circuit 2a are generated, for example, according to the duty cycle of the PWM signals stored in a waveform table. As shown in Figure 3, the control circuit unit 3 switches the waveform table used to generate the drive signals (PWM signals) input to each switching element of the inverter circuit 2a every 60 degrees of electrical angle. That is, in the example shown in Figure 3, the waveform table for generating the drive signals (PWM signals) input to each switching element of the inverter circuit 2a is switched six times per cycle every 60 degrees of electrical angle, thereby controlling the energization pattern to the three-phase coils Lu, Lv, and Lw of the motor 20 to switch in a predetermined order. Even in sinusoidal drive, the energizing pattern is switched based on the energizing switching signal S6 for switching the energizing patterns of the three-phase coils Lu, Lv, and Lw of the motor 20.

[0046] In the motor drive control device 10 of this embodiment, the electrical angle of 60 degrees, which is set as the switching timing for the power supply switching signal S6 in sinusoidal drive, is determined based on either the 180-degree section or the 360-degree section of the position detection signal Shu, depending on the rotation state of the motor 20. That is, when the rotation of the motor 20 is unstable, the 180-degree section of the position detection signal Shu is used as the reference, and one-third of the time corresponding to that section is determined as the time for the electrical angle of 60 degrees. When the rotation of the motor 20 is stable, the 360-degree section of the position detection signal Shu is used as the reference, and one-sixth of the time corresponding to that section is determined as the time for the electrical angle of 60 degrees, and this is set as the switching timing for the power supply switching signal S6.

[0047] Whether or not the rotation of the motor 20 is stable can be determined, for example, by whether or not the timing of the change in the position detection signal Shu and the switching timing of the power supply switching signal S6 for switching the energization pattern of the three-phase coils Lu, Lv, and Lw of the motor 20 are synchronized. Specifically, in sinusoidal drive, the switching timing of the power supply switching signal S6 is set to a timing of 60 degrees of electrical angle determined based on a 180-degree interval in the position detection signal Shu when the timing of the change in the position detection signal Shu and the switching timing of the power supply switching signal S6 are not synchronized (asynchronous), and is set to a timing of 60 degrees of electrical angle determined based on a 360-degree interval in the position detection signal Shu when the timing of the change in the position detection signal Shu and the switching timing of the power supply switching signal S6 are synchronized.

[0048] Furthermore, for example, whether or not the rotation of the motor 20 is stable can be determined by whether or not the rotational speed of the motor 20 is stable, that is, whether or not the difference between the target rotational speed and the actual rotational speed of the motor 20 is below a predetermined value. Specifically, the switching timing of the energization switching signal S6 in sinusoidal drive may be set to a timing of 60 degrees of electrical angle determined based on a 180-degree interval in the position detection signal Shu while the difference between the target rotational speed and the actual rotational speed of the motor 20 is not below a threshold, and may be set to a timing of 60 degrees of electrical angle determined based on a 360-degree interval in the position detection signal Shu while the difference between the target rotational speed and the actual rotational speed of the motor 20 is below a threshold.

[0049] When the rotation of the motor 20 is unstable, the switching timing of the power supply switching signal S6 in sinusoidal drive is set to a timing of 60 degrees of electrical angle determined based on a 180-degree interval in the position detection signal Shu. This allows the rotational speed of the motor 20 immediately before (change in the position detection signal Shu) to be reflected in the power supply, improving responsiveness to approach the target drive state, and consequently shortening the startup time. On the other hand, when the rotation of the motor 20 is stable, the switching timing of the power supply switching signal S6 in sinusoidal drive is set to a timing of 60 degrees of electrical angle determined based on a 360-degree interval in the position detection signal Shu. This allows the 60-degree electrical angle to be calculated by averaging even if the duty cycle of the position detection signal Shu varies, stabilizing the timing of switching the power supply pattern, and consequently suppressing vibrations.

[0050] Figure 5 shows an example of the control operation in the motor drive control device 10 according to this embodiment.

[0051] Figure 5 shows the control operation from the start of the motor 20 until the motor 20 is stably rotated. As shown in Figure 5, the control circuit unit 3 performs square wave drive when the motor 20 is started, and when it detects a position detection signal Shu for a 180-degree interval, it performs sinusoidal drive. As shown in Figure 5, during the period when the timing of the change in the position detection signal Shu after switching to sinusoidal drive and the switching timing of the power supply switching signal S6 are not synchronized (asynchronous), the switching timing of the power supply switching signal S6 is set at the timing of an electrical angle of 60 degrees determined based on the 180-degree interval of the position detection signal Shu, and sinusoidal drive is performed. Furthermore, as shown in Figure 5, during the period when the timing of the change in the position detection signal Shu after switching to sinusoidal drive and the switching timing of the power supply switching signal S6 are synchronized, the switching timing of the power supply switching signal S6 is set at the timing of an electrical angle of 60 degrees determined based on the 360-degree interval of the position detection signal Shu, and sinusoidal drive is performed.

[0052] Thus, in the motor drive control device 10 of this embodiment, the control circuit unit 3 generates a drive control signal Sd using different generation methods depending on the rotation state of the motor 20, thereby enabling both a reduction in startup time and improvement of vibration after startup.

[0053] The following describes in detail a specific configuration example of the control circuit unit 3 for realizing the functions described above. As shown in Figure 1, the control circuit unit 3 is configured as a functional unit for performing the PWM control described above, and includes a rotation speed calculation unit 31, a speed command analysis unit 32, a drive control signal generation unit 33, a power supply method instruction unit 34, and a power supply switching signal generation unit 35. The drive control signal generation unit 33 also includes a PWM command unit 331 and a PWM signal generation unit 332.

[0054] Each of the above-mentioned functional units constituting the control circuit unit 3 is realized, for example, by program processing of the MCU as the control circuit unit 3. Specifically, the processor constituting the MCU as the control circuit unit 3 performs various calculations according to the program stored in memory and controls each peripheral circuit constituting the MCU, thereby realizing the rotational speed calculation unit 31, the speed command analysis unit 32, the drive control signal generation unit 33, the energization method instruction unit 34, and the energization switching signal generation unit 35.

[0055] The rotational speed calculation unit 31 is a functional unit that calculates the actual rotational speed (actual rotational speed) of the motor 20. The rotational speed calculation unit 31 generates an actual rotational speed signal S2 indicating the actual rotational speed of the motor 20 based on the position detection signal Shu input from the position detector 25, for example, using a known calculation method, and outputs it to the PWM command unit 331 of the drive control signal generation unit 33.

[0056] The speed command analysis unit 32 receives a drive command signal Sc output from a higher-level device (not shown) located outside the motor drive control device 10. The drive command signal Sc is a signal that indicates a target value for driving the motor 20, and is, for example, a speed command signal that indicates the target rotational speed of the motor 20.

[0057] The speed command analysis unit 32 obtains information on the specified target rotational speed by analyzing the drive command signal Sc. For example, if the drive command signal Sc is a PWM signal having a duty cycle corresponding to the target rotational speed, the speed command analysis unit 32 analyzes the duty cycle of the drive command signal Sc and outputs the rotational speed information corresponding to that duty cycle as the target rotational speed signal S1 to the PWM command unit 331.

[0058] The drive control signal generation unit 33 generates a PWM signal S4 with a duty cycle determined so that the actual rotational speed of the motor 20 becomes the target rotational speed, and outputs it as a drive control signal Sd at the desired energization method and desired energization switching timing. A detailed explanation follows below.

[0059] The PWM command unit 331 receives the actual rotation signal S2 output from the rotation speed calculation unit 31 and the target rotation speed signal S1 corresponding to the drive command signal Sc output from the speed command analysis unit 32. The PWM command unit 331 also receives the energization method instruction signal S5 output from the energization method instruction unit 34 and the energization switching signal S6 output from the energization switching signal generation unit 35. Based on the target rotation speed signal S1 and the actual rotation speed signal S2, the PWM command unit 331 determines the amount of control for the motor 20 necessary to match the actual rotation speed of the motor 20 to the target rotation speed, and generates a PWM command value S3 to generate a PWM signal having a duty cycle to be used as the determined amount of control for the motor 20, according to the energization method input as the energization method instruction signal S5 and according to the timing of the 60-degree electrical angle specified by the switching timing of the energization switching signal S6.

[0060] The PWM signal generation unit 332 generates a PWM signal S4 based on the PWM command value S3 and outputs it as a drive control signal Sd.

[0061] The energization method instruction unit 34 instructs the drive control signal generation unit 33 to use a square wave drive, in which a square wave winding current flows through the coils Lu, Lv, and Lw of each phase of the motor 20, until it detects the position detection signal Shu at startup. After it detects the position detection signal Shu at startup, it instructs the drive control signal generation unit 33 to use a sinusoidal drive, in which a sinusoidal winding current flows through the coils Lu, Lv, and Lw of each phase of the motor 20.

[0062] Here, "the position detection signal Shu was detected at startup" means that a change in the level of the position detection signal Shu was detected twice. In other words, if the position detection signal Shu is detected over a 180-degree interval, it can be determined that "the position detection signal Shu was detected at startup."

[0063] The power supply switching signal generation unit 35 generates a power supply switching signal S6 having a switching timing corresponding to the rotation state of the motor 20. The power supply switching signal S6 is a signal for switching the energization pattern to the three-phase coils Lu, Lv, and Lw of the motor 20 in a predetermined order, and its switching timing indicates an electrical angle of 60 degrees. Specifically, until the position detection signal Shu is detected at startup, the power supply switching signal generation unit 35 generates a power supply switching signal S6 containing information indicating an electrical angle of 60 degrees at a timing predetermined by an internal timer. After the position detection signal Shu is detected at startup, the power supply switching signal generation unit 35 generates a power supply switching signal S6 having a switching timing of an electrical angle of 60 degrees, which is determined based on either the 180-degree section or the 360-degree section of the position detection signal Shu, depending on the rotation state.

[0064] The power switching signal generation unit 35 includes a timer 351, a signal generation unit 352, a power synchronization adjustment unit (an example of a synchronization determination unit) 353, and an electrical angle indicator unit 354. The timer 351 counts the time to define a predetermined electrical angle 60, and outputs a signal to the signal generation unit 352 each time it counts to 60 degrees.

[0065] The signal generation unit 352 generates a power switching signal S6 with a switching timing set to an electrical angle of 60 degrees, received from the timer 351, until it detects a position detection signal Shu during startup.

[0066] After detecting the position detection signal Shu at startup, the signal generation unit 352 generates a power-on switching signal S6 having a switching timing set to the timing of 60 degrees of electrical angle determined based on either the 180-degree section or the 360-degree section of the position detection signal Shu, rather than the timing of 60 degrees of electrical angle received from the timer 351, depending on the rotation state of the motor 20. Specifically, the signal generation unit 352 generates a power-on switching signal S6 having a switching timing set to the timing determined based on the electrical angle generation reference instruction signal S8 output from the electrical angle instruction unit 354. The electrical angle generation reference instruction signal S8 is a signal that includes an instruction on whether to use the 180-degree section or the 360-degree section of the position detection signal Shu as the reference for determining the 60-degree electrical angle.

[0067] When the signal generation unit 352 receives an electrical angle generation reference instruction signal S8 which includes an instruction to set an electrical angle of 60 degrees based on the 180-degree interval in the position detection signal Shu, it determines the timing of the electrical angle of 60 degrees based on the 180-degree interval in the position detection signal Shu and generates a power switching signal S6 having a switching timing set at the determined timing.

[0068] When the signal generation unit 352 receives an electrical angle generation reference instruction signal S8 which includes an instruction to set an electrical angle of 60 degrees based on the 360-degree interval in the position detection signal Shu, it determines the timing of the electrical angle of 60 degrees based on the 360-degree interval in the position detection signal Shu and generates a power switching signal S6 having a switching timing set at the determined timing.

[0069] The electrical angle indicator unit 354 generates an electrical angle generation reference indicator signal S8, which includes an instruction on whether to use a 180-degree interval or a 360-degree interval in the position detection signal Shu as the reference for generating an electrical angle of 60 degrees, depending on the rotation state of the motor 20.

[0070] The electrical angle indicator unit 354 generates an electrical angle generation reference indicator signal S8, which includes an instruction on whether to use a 180-degree interval or a 360-degree interval in the position detection signal Shu as the reference for determining an electrical angle of 60 degrees, based on a synchronization notification signal S7 generated by the energization synchronization adjustment unit 353. The synchronization notification signal S7 is a signal that includes synchronization status information, which is information on whether or not the timing of the change in the position detection signal Shu and the switching timing of the energization switching signal S6 are synchronized.

[0071] The synchronization information included in the synchronization notification signal S7 is one form of information indicating whether or not the rotation of the motor 20 is in a stable state. In this embodiment, the rotation state of the motor 20 is determined by whether or not the timing of the change in the position detection signal Shu and the switching timing of the power supply switching signal S6 are synchronized, but this is not limited to this. If the rotation state of the motor 20 is determined by other criteria, the synchronization notification signal S7 can be a signal that includes other information indicating whether or not the rotation state of the motor 20 is stable.

[0072] When the electrical angle indicator unit 354 receives a synchronization notification signal S7 from the power supply synchronization adjustment unit 353 indicating that the timing of the change in the position detection signal Shu and the switching timing of the power supply switching signal S6 are synchronized, it determines that the rotation of the motor 20 is in a stable state, generates an electrical angle generation reference instruction signal S8 which includes an instruction that the generation of an electrical angle of 60 degrees should be based on the 360-degree interval of the position detection signal Shu, and outputs it to the signal generation unit 352 of the power supply switching signal generation unit 35.

[0073] If the electrical angle indicator unit 354 receives a synchronization notification signal S7 from the power supply synchronization adjustment unit 353 indicating that the timing of the change in the position detection signal Shu and the switching timing of the power supply switching signal S6 are not synchronized, it determines that the rotation of the motor 20 is not in a stable state, and generates an electrical angle generation reference instruction signal S8 which includes an instruction that the generation of an electrical angle of 60 degrees should be based on the 180-degree interval in the position detection signal Shu, and outputs it to the signal generation unit 352 of the power supply switching signal generation unit 35.

[0074] The energization synchronization adjustment unit 353 determines whether the timing of the change in the position detection signal Shu and the switching timing of the energization switching signal S6 are synchronized, based on the position detection signal Shu input from the position detector 25 and the PWM command value S3 input from the PWM command unit 331, and generates a synchronization notification signal S7 that includes synchronization status information. Since the PWM command value S3 includes information on the timing of an electrical angle of 60 degrees specified by the energization switching signal S6, the switching timing of the energization switching signal S6 can be determined based on the PWM command value S3.

[0075] Here, we will explain the synchronization between the position detection signal Shu and the power switching signal S6.

[0076] Figure 6 illustrates the relationship between the position detection signal Shu and the power switching signal S6. Figure 6 shows six patterns of timing for the position detection signal Shu in relation to the timing of the power switching signal S6 at an electrical angle of 60 degrees. In Figure 6, the dashed lines extending vertically indicate the rising or falling edge of the power switching signal S6.

[0077] In this embodiment, during the 360-degree electrical angle in which the energizing switching signal S6, which indicates a timing of 60 degrees electrical angle, is output six times, the winding current flowing through the U-phase coil Lu of the motor 20 forms a single sinusoidal waveform. That is, the time when the energizing switching signal S6 is output six times corresponds to the time of one rotation period of the motor 20. The energizing synchronization adjustment unit 353 can identify the six timings corresponding to (1) to (6) of the energizing switching signal S6 shown in Figure 6 by counting the sinusoidal drive PWM command value S3.

[0078] The top row of Figure 6 shows the relationship between the position detection signal Shu (solid line) and the power switching signal S6 when synchronized, while (a) to (e) show the relationship between the position detection signal Shu (dashed line) and the power switching signal S6 when not synchronized.

[0079] In the example shown in Figure 6, the power synchronization adjustment unit 353 determines that synchronization is occurring when the falling edge of the position detection signal Shu is detected at timing (1) of the power switching signal S6, and the rising edge of the position detection signal Shu is detected at timing (4) of the power switching signal S6.

[0080] On the other hand, the energization synchronization adjustment unit 353 determines that synchronization is not occurring if the phase of the position detection signal Shu, which indicates the rotational position of the rotor, is either ahead or behind the energization switching signal S6. Such cases are shown in Figure 6 (a) to (e).

[0081] Case (a) is when the detection timing of the position detection signal Shu is delayed by one step relative to the power switching signal S6. That is, the falling edge of the position detection signal Shu is detected at timing (2) of the power switching signal S6, and the rising edge of the position detection signal Shu is detected at timing (5) of the power switching signal S6.

[0082] Case (b) is when the detection timing of the position detection signal Shu is delayed by two steps relative to the power switching signal S6. That is, the falling edge of the position detection signal Shu is detected at timing (3) of the power switching signal S6, and the rising edge of the position detection signal Shu is detected at timing (6) of the power switching signal S6.

[0083] Case (c) is when the detection timing of the position detection signal Shu is delayed by three steps relative to the power switching signal S6. That is, the falling edge of the position detection signal Shu is detected at timing (4) of the power switching signal S6, and the rising edge of the position detection signal Shu is detected at timing (1) of the power switching signal S6.

[0084] Case (d) is when the detection timing of the position detection signal Shu is delayed by four steps relative to the power switching signal S6. That is, the falling edge of the position detection signal Shu is detected at timing (5) of the power switching signal S6, and the rising edge of the position detection signal Shu is detected at timing (2) of the power switching signal S6.

[0085] Case (e) is when the detection timing of the position detection signal Shu is delayed by 5 units relative to the power switching signal S6. That is, the falling edge of the position detection signal Shu is detected at timing (6) of the power switching signal S6, and the rising edge of the position detection signal Shu is detected at timing (3) of the power switching signal S6.

[0086] The power supply synchronization adjustment unit 353 determines whether the timing of the change in the position detection signal Shu and the switching timing of the power supply switching signal S6 are synchronized, based on the position detection signal Shu and the PWM command value S3. Since the PWM command value S3 includes information on the timing of the electrical angle of 60 degrees specified by the power supply switching signal S6, the switching timing of the power supply switching signal S6 can be determined based on the PWM command value S3.

[0087] If the power supply synchronization adjustment unit 353 determines, for example, that the case corresponds to the top row of Figure 6, it determines that the timing of the change in the position detection signal Shu and the switching timing of the power supply switching signal S6 are synchronized, and generates a synchronization notification signal S7 that includes synchronization status information indicating that the timing of the change in the position detection signal Shu and the switching timing of the power supply switching signal S6 are synchronized.

[0088] If the power supply synchronization adjustment unit 353 determines, for example, that the case falls under one of cases (a) through (e) in Figure 6, it determines that the position detection signal Shu and the power supply switching signal S6 are not synchronized, and generates a synchronization notification signal S7 that includes synchronization status information indicating that the position detection signal Shu and the power supply switching signal S6 are not synchronized.

[0089] Figure 7 shows an example of the processing flow for power supply control in the control circuit unit 3. In Figure 7, the control circuit unit 3 first instructs to energize at 120 degrees during startup (step S101). Specifically, the energization method instruction unit 34 generates an energization method instruction signal S5 indicating that square wave driving by energizing at 120 degrees is to be instructed immediately after startup and outputs it to the PWM command unit 331 of the drive control signal generation unit 33. The energization switching signal generation unit 35 outputs an energization switching signal S6 indicating a predetermined timing of an electrical angle of 60 degrees to the PWM command unit 331 of the drive control signal generation unit 33.

[0090] The control circuit unit 3 determines whether or not it was able to acquire (detect) the position detection signal Shu (step S102). Specifically, the energization method indicator unit 34 determines, for example, whether or not it was able to acquire (detect) the position detection signal Shu for a 180-degree section. If the control circuit unit 3 cannot determine that it was able to acquire the position detection signal Shu (step S102: NO), it waits until it can determine this.

[0091] If the control circuit unit 3 determines that it has been able to acquire the position detection signal Shu (step S102: YES), it instructs sinusoidal drive (step S103). Specifically, the energization method instruction unit 34 generates an energization method instruction signal S5 indicating that sinusoidal drive is to be instructed and outputs it to the PWM command unit 331.

[0092] If the control circuit unit 3 determines that it has been able to acquire the position detection signal Shu (step S102: YES), it determines whether the timing of the change in the position detection signal Shu and the switching timing of the power supply switching signal S6 are synchronized (step S104). Specifically, the power supply synchronization adjustment unit 353 determines whether the timing of the change in the position detection signal Shu and the switching timing of the power supply switching signal S6 are synchronized based on the position detection signal Shu and the PWM command value S3.

[0093] If the control circuit unit 3 determines that the timing of the change in the position detection signal Shu and the switching timing of the power supply switching signal S6 are not synchronized (step S104: NO), it instructs that an electrical angle of 60 degrees be determined based on a 180-degree interval in the position detection signal Shu (step S105). Specifically, the power supply synchronization adjustment unit 353 determines that the timing of the change in the position detection signal Shu and the switching timing of the power supply switching signal S6 are not synchronized, and outputs a synchronization notification signal S7 to the electrical angle indicator unit 354, which includes synchronization status information indicating that the signals are not synchronized. Upon receiving this synchronization notification signal S7, the electrical angle indicator unit 354 outputs an electrical angle generation reference instruction signal S8 to the signal generation unit 352, which instructs that an electrical angle of 60 degrees be generated based on a 180-degree interval in the position detection signal Shu.

[0094] On the other hand, if the control circuit unit 3 determines that the timing of the change in the position detection signal Shu and the switching timing of the power supply switching signal S6 are synchronized (step S104: YES), it instructs the unit to determine an electrical angle of 60 degrees based on the 360-degree interval in the position detection signal Shu (step S106). Specifically, the power supply synchronization adjustment unit 353 determines that the timing of the change in the position detection signal Shu and the switching timing of the power supply switching signal S6 are synchronized, and outputs a synchronization notification signal S7 to the electrical angle indicator unit 354, which includes synchronization status information indicating that synchronization is occurring. Upon receiving this synchronization notification signal S7, the electrical angle indicator unit 354 outputs an electrical angle generation reference instruction signal S8 to the signal generation unit 352, which instructs the unit to generate an electrical angle of 60 degrees based on the 360-degree interval in the position detection signal Shu.

[0095] The signal generation unit 352 generates an electrical angle of 60 degrees based on the interval in the position detection signal Shu instructed by the processing in steps S105 and S106, and outputs it to the PWM command unit 331 as a power switching signal S6.

[0096] The control circuit unit 3 determines whether or not to stop driving the motor 20 (step S107). If it decides to stop driving the motor 20 (step S107: YES), it terminates the process. If it decides not to stop driving the motor 20 (step S107: YES), it returns to step S104 (step S107: NO) and continues the process.

[0097] In the motor drive control device 10 according to this embodiment, the control circuit unit 3 generates an energization switching signal S6 to switch the energization pattern to the three-phase coils Lu, Lv, and Lw of the motor 20 at a timing determined based on either a 180-degree interval or a 360-degree interval in the position detection signal Shu, according to the rotation state of the motor 20, and generates a drive control signal Sd to drive the motor 20 in a sinusoidal wave by switching the energization pattern based on the energization switching signal S6.

[0098] According to this, in sinusoidal drive, if the rotation of the motor 20 is not stable, a power switching signal S6 is generated to switch the energizing pattern to the three-phase coils Lu, Lv, and Lw of the motor 20 at a timing determined based on a 180-degree interval in the position detection signal Shu. This allows the rotational speed of the motor 20 immediately before (change in the position detection signal Shu) to be reflected in the energizing, improving responsiveness to approach the target drive state, and consequently shortening the startup time. On the other hand, when the rotation of the motor 20 is stable, a power switching signal S6 is generated to switch the energizing pattern to the three-phase coils Lu, Lv, and Lw of the motor 20 at a timing determined based on a 360-degree interval in the position detection signal Shu. This allows the electrical angle of 60 degrees to be calculated by averaging even if the duty cycle of the position detection signal Shu varies, thus stabilizing the timing of switching the energizing pattern and consequently suppressing vibration.

[0099] In the motor drive control device 10 according to this embodiment, the power supply switching signal generation unit 35 determines the rotation state of the motor 20 by determining whether the timing of the change of the position detection signal Shu and the switching timing of the power supply switching signal S6 are synchronized.

[0100] According to this, the rotation state of the motor 20 can be determined based on the position detection signal Shu and the PWM command value S3, thus simplifying the configuration for determining the rotation state of the motor 20.

[0101] In the motor drive control device 10 according to this embodiment, the control circuit unit 3 generates a PWM signal (an example of a control signal) S4 for driving the motor 20 with a square wave as a drive control signal Sd before detecting the position detection signal Shu when the motor 20 is started, and generates a PWM signal (an example of a control signal) S4 for driving the motor 20 with a sine wave as a drive control signal Sd after detecting the position detection signal Shu when the motor 20 is started.

[0102] According to this, when the motor 20 is in a state where sinusoidal drive is possible, a drive control signal Sd for sinusoidal drive can be generated. Sine wave drive generates a drive signal (PWM signal) with a predetermined duty cycle for each PWM period at every 360 degrees of electrical angle, switches each switching element of the inverter circuit 2a, and controls the winding current of the motor 20 to be sinusoidal. The timing of generating the PWM signal at every 360 degrees of electrical angle is determined from the change time of the immediately preceding position detection signal Shu, so at startup the motor 20 is driven with a square wave, and when the change time of the position detection signal Shu can be detected, it switches to sinusoidal drive.

[0103] <<Extension of the Embodiment>> Although the present invention has been specifically described above based on embodiments, it goes without saying that the present invention is not limited thereto and can be modified in various ways without departing from its essence.

[0104] For example, in the above embodiment, the method described with reference to Figure 6 was used to determine whether the timing of the change in the position detection signal Shu and the switching timing of the power supply switching signal S6 are synchronized. However, the method is not limited to this, and any known synchronization determination method can be used.

[0105] Furthermore, if the energization synchronization adjustment unit 353 determines that the system is asynchronous, it may include information indicating the degree of asynchronous operation in the synchronization notification signal S7, for example, information indicating which of cases (a) to (e) shown in Figure 6 applies. In this case, for example, information indicating which of cases (a) to (e) shown in Figure 6 applies may be included in the electrical angle generation reference instruction signal S8 generated by the electrical angle instruction unit 354 or the energization switching signal S6 generated by the signal generation unit 352. Depending on the information indicating the degree of asynchronous operation included in the energization switching signal S6, the drive control signal generation unit 33 can adjust the phase of the PWM signal S4 generated as the drive control signal Sd.

[0106] Furthermore, in the above embodiment, the motor 20 is not limited to a brushless DC motor. Also, the motor 20 is not limited to a 3-phase motor, but may have a configuration of 2 or more phases.

[0107] In the above embodiment, after starting sinusoidal drive, the process of first calculating an electrical angle of 60 degrees based on a 180-degree interval and then calculating an electrical angle of 60 degrees based on a 360-degree interval after synchronization is achieved is shown. However, these switching processes are not limited to startup. For example, if synchronization is lost again due to a sudden deceleration after synchronization has been achieved, the process may be to switch from calculating an electrical angle of 60 degrees based on a 360-degree interval to calculating an electrical angle of 60 degrees based on a 180-degree interval, and then calculate an electrical angle of 60 degrees based on a 360-degree interval after synchronization is achieved again.

[0108] In the above embodiment, the use of a Hall IC as the position detector 25 is illustrated, but the invention is not limited to this. For example, a Hall element, encoder, resolver, etc., may be provided as the position detector 25, and their detection signals may be input to the motor drive control device 10 as the position detection signal Shu. Furthermore, the number of position detectors 25 is not particularly limited. In addition, the motor drive control device 10 may calculate the rotational speed and electrical angle of the motor 20 by known position sensorless calculation methods such as synchronous detection using winding voltage, without providing position detectors 25.

[0109] In the above embodiment, the case of energizing at 120 degrees as a rectangular wave drive was described as an example, but other energizing angles such as 150 degrees may also be used.

[0110] Furthermore, while the example given illustrates a case where each functional part of the control circuit unit 3 is implemented by the program processing of the MCU, the case is not limited to this, and some or all of the functional parts of the control circuit unit 3 may be implemented by dedicated circuits (hardware).

[0111] Furthermore, the flowchart described above is merely an example and is not limited to these steps. For example, other processes may be inserted between each step, or the processes may be parallelized. [Explanation of Symbols]

[0112] 1...Motor unit, 2...Motor drive unit, 2a...Inverter circuit, 2b...Pre-drive circuit, 3...Control circuit unit, 31...Rotation speed calculation unit, 32...Speed ​​command analysis unit, 33...Drive control signal generation unit, 331...PWM command unit, 332...PWM signal generation unit, 34...Power supply method indicator unit, 35...Power supply switching signal generation unit, 351...Timer, 352...Signal generation unit, 353...Power supply synchronization adjustment unit (example of synchronization determination unit), 354...Electrical angle indicator unit, 10...Motor drive control device, 20...Motor, 25...Position detector (position detection signal output) (Example of power unit), Shu...position detection signal, Sc...drive command signal, Sd...drive control signal, S1...target rotational speed signal, S2...actual rotational speed signal, S3...PWM command value, S4...PWM signal (example of control signal), S5...energy supply method instruction signal, S6...energy supply switching signal, S7...synchronous notification signal, S8...electrical angle generation reference instruction signal, Lu...U-phase coil, Lv...V-phase coil, Lw...W-phase coil, Vuh, Vul, Vvh, Vvl, Vwh, Vwl...drive signals, VU, WU, WV, UV, UW, VW...energy supply pattern.

Claims

1. A motor drive unit that selectively energizes the coils of multiple phases of the motor, A control circuit unit outputs a drive control signal to the motor drive unit, thereby switching the energization pattern of the multiple phase coils energized by the motor drive unit in a predetermined order. A position detection signal output unit outputs a position detection signal corresponding to the position of the rotor of the motor, Equipped with, The aforementioned control circuit unit is A power supply switching signal generation unit generates a power supply switching signal for switching the energizing pattern to the multiple phase coils of the motor at a timing determined based on either a 180-degree interval or a 360-degree interval in the position detection signal, according to the rotation state of the motor. The system includes a drive control signal generation unit that switches the energization pattern based on the energization switching signal and generates a control signal for sinusoidal driving of the motor as the drive control signal, The aforementioned power supply switching signal generation unit is: A synchronization determination unit that determines whether the timing of the change in the position detection signal and the switching timing of the power supply switching signal are synchronized, The synchronization determination unit generates the power supply switching signal at a timing determined based on the 180-degree interval when it determines that the timing of the change in the position detection signal and the switching timing of the power supply switching signal are not synchronized, and the signal generation unit generates the power supply switching signal at a timing determined based on the 360-degree interval when it determines that the timing of the change in the position detection signal and the switching timing of the power supply switching signal are synchronized. Motor drive control device.

2. A motor drive unit that selectively energizes multiple phase coils of a motor, A control circuit unit outputs a drive control signal to the motor drive unit, thereby switching the energization pattern of the multiple phase coils energized by the motor drive unit in a predetermined order. A position detection signal output unit outputs a position detection signal corresponding to the position of the rotor of the motor, Equipped with, The aforementioned control circuit unit is A power supply switching signal generation unit generates a power supply switching signal for switching the energizing pattern to the multiple phase coils of the motor at a timing determined based on either a 180-degree interval or a 360-degree interval in the position detection signal, according to the rotation state of the motor. The system includes a drive control signal generation unit that switches the energization pattern based on the energization switching signal and generates a control signal for sinusoidal driving of the motor as the drive control signal, The aforementioned power supply switching signal generation unit is: The signal generation unit generates the power supply switching signal at a timing determined based on a 180-degree interval in the position detection signal as long as the difference between the target rotational speed and the actual rotational speed of the motor is not less than a predetermined value, and generates the power supply switching signal at a timing determined based on a 360-degree interval in the position detection signal as long as the difference between the target rotational speed and the actual rotational speed of the motor is less than or equal to a predetermined value. Motor drive control device.

3. In the motor drive control device according to claim 1, The aforementioned control circuit unit is The motor further includes an energization method instruction unit that, before detecting the position detection signal at the start of the motor, instructs the drive control signal generation unit to generate a control signal for driving the motor with a square wave as the drive control signal, and after detecting the position detection signal at the start of the motor, instructs the drive control signal generation unit to generate a control signal for driving the motor with a sinusoidal wave as the drive control signal. Motor drive control device.

4. In the motor drive control device according to claim 3, When the drive control signal generation unit receives an instruction from the energization method instruction unit to generate a control signal for driving the motor with a rectangular wave, it generates a control signal for energizing at 120 degrees as the drive control signal. Motor drive control device.

5. A motor drive control device according to any one of claims 1 to 4, The motor comprises Motor unit.

6. A motor drive control method using a motor drive control device comprising: a motor drive unit that selectively energizes multiple phase coils of a motor; a control circuit unit that outputs a drive control signal to the motor drive unit, thereby switching the energization pattern of the multiple phase coils energized by the motor drive unit in a predetermined order; and a position detector that outputs a position detection signal corresponding to the position of the rotor of the motor, wherein The control circuit unit generates a power switching signal to switch the power supply pattern to the multiple phase coils of the motor at a timing determined based on either a 180-degree interval or a 360-degree interval in the position detection signal, according to the rotation state of the motor. The second step includes switching the energization pattern based on the energization switching signal and generating a control signal for sinusoidal driving the motor as the drive control signal, In the first step described above, A synchronization determination substep for determining whether the timing of the change in the position detection signal and the switching timing of the power supply switching signal are synchronized, The system includes a signal generation substep in which, if it is determined in the synchronization determination substep that the timing of the change in the position detection signal and the switching timing of the power supply switching signal are not synchronized, the power supply switching signal is generated at a timing determined based on the 180-degree interval, and if it is determined in the synchronization determination substep that the timing of the change in the position detection signal and the switching timing of the power supply switching signal are synchronized, the power supply switching signal is generated at a timing determined based on the 360-degree interval. Motor drive control method.

7. A motor drive control method using a motor drive control device comprising: a motor drive unit that selectively energizes multiple phase coils of a motor; a control circuit unit that outputs a drive control signal to the motor drive unit, thereby switching the energization pattern of the multiple phase coils energized by the motor drive unit in a predetermined order; and a position detector that outputs a position detection signal corresponding to the position of the rotor of the motor, wherein The control circuit unit generates a power switching signal to switch the power supply pattern to the multiple phase coils of the motor at a timing determined based on either a 180-degree interval or a 360-degree interval in the position detection signal, according to the rotation state of the motor. The second step includes switching the energization pattern based on the energization switching signal and generating a control signal for sinusoidal driving the motor as the drive control signal, In the first step described above, The system has a signal generation substep which generates the power switching signal at a timing determined based on a 180-degree interval in the position detection signal as long as the difference between the target rotational speed and the actual rotational speed of the motor is not less than a predetermined value, and generates the power switching signal at a timing determined based on a 360-degree interval in the position detection signal as long as the difference between the target rotational speed and the actual rotational speed of the motor is less than or equal to a predetermined value. Motor drive control method.

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