JP2014007894A - Motor control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor control device capable of performing control up to a higher rotating speed at low cost.SOLUTION: The motor control device comprises: position detection means (11) which outputs a rotating position signal of a rotor (100a); a position detection section (25) which generates a capture signal each time the rotor rotates at a predetermined electric angle; a timer section (26) which generates an interrupt trigger signal in timing determined on the basis of the capture signal; a calculation section (24) which calculates a PWM duty by executing interrupt processing in accordance with the interrupt trigger signal; and a PWM output section (27) which outputs a PWM signal on the basis of the calculated PWM duty. The timer section includes a function for changing the generation timing of the interrupt trigger signal in such a manner that a generation cycle of the interrupt trigger signal becomes a time corresponding to n-times ((n) is an integer equal to or more than 2) as much as the predetermined electric angle in the case where the interrupt processing is not completed within a time corresponding to the predetermined electric angle.

Description

  The present invention relates to a motor control device that PWM-controls a motor including a rotor and a stator provided with multiphase windings.

  Conventionally, as described in Patent Document 1, for example, a motor control device that performs PWM control on a motor including a rotor and a stator provided with a multiphase winding is known.

  In this motor control device, the rotational position of the rotor is detected for each predetermined electrical angle (for example, electrical angle of 60 degrees) by the position detection circuit. Then, interrupt processing (software processing) by the microcomputer, such as calculation of PWM duty, is executed at the timing of rotational position detection.

JP 2009-11134 A

  By the way, the interrupt processing of the microcomputer must be completed within the rotation time of the predetermined electrical angle described above. For this reason, conventionally, the performance of the microcomputer is determined so that the time required for the interrupt processing of the microcomputer is shorter than the rotation time of the predetermined electrical angle at the maximum rotation of the motor. Therefore, the standard rotational speed is far from the maximum rotational speed, and even when the high rotational speed is used irregularly, a microcomputer having a high-performance CPU must be used, which increases the cost. there were.

  Further, when a motor with a higher maximum speed is controlled by a motor controller of the same specification, there may be a problem that the interrupt process of the microcomputer does not end within the rotation time of a predetermined electrical angle.

  In view of the above problems, an object of the present invention is to provide a motor control device that can control up to a higher rotational speed at low cost.

  In order to achieve the above object, the present invention provides a motor control device that PWM-controls a motor (100) including a rotor (100a) and a stator provided with a multiphase winding, and a rotational position signal of the rotor is obtained. Based on the position detection means (11) for output, the position detection unit (25) for generating a capture signal every time the rotor rotates by a predetermined electrical angle based on the rotation position signal, and the timing determined based on the capture signal, A timer unit (26) that generates an interrupt trigger signal, an interrupt process based on the interrupt trigger signal, a calculation unit (24) that calculates a PWM duty, and a PWM output that outputs a PWM signal based on the calculated PWM duty Unit (27), and the timer unit does not end interrupt processing in the arithmetic unit within an interrupt interval corresponding to a predetermined electrical angle. As the generation cycle of the interrupt trigger signal is time corresponding to n times (n is an integer of 2 or more) of a predetermined electrical angle, and having a function of changing the timing of generating an interrupt trigger signal.

  When the interrupt process is completed within a time corresponding to a predetermined electrical angle (hereinafter, referred to as a first rotation time), the timer unit generates an interrupt trigger signal with the first rotation time as a generation cycle. In other words, an interrupt trigger signal is generated for each capture signal. On the other hand, when the motor is at a high speed and the interruption process is not completed within the first rotation time, a time corresponding to n times the predetermined electrical angle (n is an integer of 2 or more) (hereinafter referred to as the second rotation time). An interrupt trigger signal is generated as a generation cycle. In other words, an interrupt trigger signal is generated not for every capture signal but for every other capture signal, for example. Thus, since the timing for generating the interrupt trigger signal can be changed, it is possible to control up to a higher rotational speed without using a microcomputer having a high-performance CPU.

1 is a diagram illustrating a schematic configuration of a motor control system to which a motor control device according to a first embodiment is applied. It is a figure which shows arrangement | positioning of a motor and a Hall element. It is a figure which shows schematic structure of a timer part among motor control apparatuses. It is a figure which shows schematic structure of a time comparison control part among timer parts. It is a flowchart which shows the process performed in a PWM output. It is a timing chart which shows the generation timing of a capture signal and an interrupt trigger signal, and the processing timing of a software processing part. It is a figure which shows schematic structure of a timer part among the motor control apparatuses which concern on 2nd Embodiment. It is a figure which shows schematic structure of a time comparison control part among timer parts. It is a flowchart which shows a characteristic part among the processes performed in a PWM output. It is a timing chart which shows a generation timing of a capture signal, a processing end timing signal, and an interrupt trigger signal, and a processing timing of a software processing unit. It is a figure which shows schematic structure of a timer part among the motor control apparatuses which concern on 3rd Embodiment. It is a flowchart which shows a characteristic part among the processes performed in a PWM output. It is a timing chart which shows the generation timing of a capture signal, a status signal, and an interrupt trigger signal, and the processing timing of a software processing part.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each embodiment, common or related elements are given the same reference numerals.

(First embodiment)
As shown in FIGS. 1 and 2, the motor 100 includes, for example, a rotor 100a having a permanent magnet and a stator 100b having a three-phase winding. The motor control apparatus 10 that performs PWM control of the motor 100 includes a hall element 11 as a position detection unit and a microcomputer 12 (hereinafter referred to as a microcomputer 12).

  The hall element 11 is attached to the motor 100 in order to detect the rotational position of the rotor 100a. In the present embodiment, as shown in FIG. 2, the three hall elements 11 are provided, and the three hall elements 11 are arranged every 120 degrees with respect to the rotation center of the rotor 100a.

  Note that the position detecting means is not limited to the Hall element 11, and other well-known means, for example, a circuit for processing the induced voltage of each phase of the motor 100 may be employed. Further, the number of Hall elements 11 is not limited to the above example.

  As shown in FIG. 1, the microcomputer 12 has a CPU 20, a ROM 21, a RAM 22, a motor control circuit 23, and an address bus / data bus (not shown). The CPU 20 uses the RAM 22 according to a control program stored in the ROM 21 and executes software processing. That is, the CPU 20, ROM 21, and RAM 22 function as the software processing unit 24. The software processing unit 24 corresponds to a calculation unit described in the claims. Further, the CPU 20 controls the motor control circuit 23 via the address bus / data bus.

  The motor control circuit 23 includes a position detection unit 25 that generates a capture signal, a timer unit 26 that generates an interrupt trigger signal, and a PWM output unit 27 that outputs a PWM signal.

  The position detection unit 25 generates a capture signal and outputs it to the timer unit 26 every time the rotor 100 a rotates by a predetermined electrical angle based on the rotation position signal output from the Hall element 11. In this embodiment, as shown in FIG. 2, the rotor 100a has two magnetic poles, and the Hall elements 11 are arranged every 120 degrees, so that a capture signal is generated every 60 electrical angles as is well known. . The signal output from the position detection unit 25 to the timer unit 26 is “0” or “1”, and the capture signal is “1”. Further, the position detection unit 25 generates an energization timing generation signal based on the rotational position signal output from the Hall element 11 and outputs the generated energization timing signal to the PWM output unit 27. This energization timing generation signal indicates commutation timing, and is generated every 60 electrical angles, like the capture signal. The signal output from the position detection unit 25 to the PWM output unit 27 is “0” or “1”, and the energization timing signal is “1”.

  The timer unit 26 generates an interrupt trigger signal at a timing determined based on the capture signal and outputs the interrupt trigger signal to the software processing unit 24. The motor control device 10 according to the present embodiment is characterized by the timer unit 26, and details thereof will be described later.

  The software processing unit 24 executes an interrupt process according to the interrupt trigger signal and calculates the PWM duty. Specifically, the rotation speed is calculated from the interrupt trigger signal. Then, PI control is performed with the deviation between the calculated rotation speed and the set speed, and the PWM duty is calculated.

  The PWM output unit 27 outputs a PWM signal based on the calculated PWM duty. Based on the energization timing generation signal output from the position detection unit 25, the output of the PWM signal, that is, the energization pattern to the three-phase winding is switched. This PWM signal is input to the inverter 102 via the gate driver 101.

  Next, the timer unit 26 will be described with reference to FIGS.

  As shown in FIG. 3, the timer unit 26 includes a capture control unit 30, a timer counter 31, a time comparison control unit 32, and a storage unit 33. The capture control unit 30 calculates the time from when the capture signal is input until the next capture signal is input, from the timer count value of the timer counter 31 (for example, a free-run timer). As described above, since the capture signal is generated every 60 degrees of electrical angle, the time calculated by the capture control unit 30 is the time required for the rotor 100a to rotate 60 degrees of electrical angle. Hereinafter, this time is referred to as 60 ° rotation time. Then, the time comparison control unit 32 compares the calculated 60-degree rotation time with a reference time preset in the storage unit 33, and selectively generates and outputs an interrupt trigger signal according to the comparison result. . The reference time is set by adding a predetermined margin to the software processing time (PWM duty calculation time) by the software processing unit 24.

  The time comparison control unit 32 includes a time comparator 40, a NOT gate 41, an interrupt mask control unit 42, and an OR gate 43. The time comparator 40 compares the 60-degree rotation time calculated by the capture control unit 30 with the reference time read from the storage unit 33. When the 60-degree rotation time is longer than the reference time, “1” is set. Output. On the other hand, when the 60 degree rotation time is shorter than the reference time, “0” is output. This determination signal is input to the OR gate 43 and also input to the interrupt mask control unit 42 via the NOT gate 41.

  When “1” is output from the time comparator 40, “0” is input to the interrupt mask control unit 42, and the interrupt mask control unit 42 outputs “0” to the OR gate 43. Therefore, “1” is output from the OR gate 43, that is, the timer unit 26. That is, an interrupt trigger signal is generated and output.

  On the other hand, when “0” is output from the time comparator 40, “1” is input to the interrupt mask control unit 42. The interrupt mask control unit 42 accumulates the input signal and outputs 1 when the value exceeds 1. That is, when “1” is input for the first time, the accumulated value is “1”, and “0” is output from the interrupt mask control unit 42. Therefore, both inputs to the OR gate 43 are “0”, and “0” is output from the OR gate 43 (timer unit 26). That is, no interrupt trigger signal is generated. When “2” is input for the second time, the accumulated value is “2” and exceeds 1, and therefore “1” is output from the interrupt mask control unit 42. Therefore, “1” is output from the OR gate 43 (timer unit 26). That is, an interrupt trigger signal is generated and output. Further, the interrupt mask control unit 42 resets the accumulated value when “0” is input or the accumulated value becomes “2” and “1” is output. In other words, when “1” is output from the OR gate 43, that is, when the interrupt trigger gate signal is output, the accumulated value is reset.

  As described above, in this embodiment, when the 60-degree rotation time is longer than the reference time, the interrupt trigger signal is generated with the 60-degree rotation time as a generation period. When the 60-degree rotation time is shorter than the reference time, the interrupt trigger signal generation timing is masked once, and the interrupt trigger signal is generated with the 120-degree rotation time as the generation period.

  In addition, the interrupt mask control unit 42 outputs “1” and also outputs a mask signal indicating that the masking has been performed once to the software processing unit 24. Therefore, when the mask signal is input, the software processing unit 24 calculates the rotation speed as 120-degree rotation time.

  Next, processing executed in PWM output will be described with reference to FIG.

  When the ignition switch is turned on and electric power is supplied, the motor control device 10 starts operating and executes the process of FIG. And the process shown below is repeatedly performed in the state with which electric power was supplied.

  First, the hall element 11 detects the rotational position of the rotor 100a and outputs a rotational position signal (step S10). This rotational position signal is input to the microcomputer 12, and the position detection unit 25 generates a capture signal every time the rotor 100a rotates 60 degrees from the change timing of the rotational position signal (step S11). Further, the position detection unit 25 generates an energization timing generation signal from the change timing of the rotational position signal (step S12).

  Next, as described above, the timer unit 26 generates a 60-degree rotation time based on the capture signal (step S13). Then, the generated 60-degree rotation time is compared with the reference time (step S14). As a result, when the 60-degree rotation time is longer than the reference time, an interrupt trigger signal is generated (step S16).

  On the other hand, if the 60-degree rotation time is shorter than the reference time in step S14, it is determined whether or not the accumulated value is greater than 1 (step S15). That is, it is determined whether or not the mask for generating the interrupt trigger signal is the first time. In step S15, only when the accumulated value is “1”, that is, when the mask is the first time, the process returns to step 10, and steps S10 to S14 are repeated. In step S14, if the 60-degree rotation time is longer than the reference time, an interrupt trigger signal is generated (step S16). In this case, an interrupt trigger signal is generated with a 120-degree rotation time as a generation cycle. In step S15, an interrupt trigger signal is also generated when the accumulated value is “2” (step S16). In this case as well, an interrupt trigger signal is generated with a 120-degree rotation time as a generation cycle.

  As described above, along with the generation of the interrupt trigger signal, the timer unit 26 (interrupt mask control unit 42) resets the accumulated value (step S17). Then, the software processing unit 24 executes the above-described software processing based on the interrupt trigger signal and the above-described mask signal. That is, the PWM duty is calculated (step S18). The PWM output unit 27 outputs a PWM signal to the gate driver 101 based on the calculated PWM duty and energization timing generation signal.

  The software processing (step S18) by the software processing unit 24 is software processing performed by the CPU 20 according to the control program as described above, and other processing is performed by the motor control circuit 23 configured in the microcomputer 2. This is a process performed by (hardware logic).

  Next, the effect of the characteristic part of the motor control apparatus 10 according to the present embodiment will be described.

  When the 60 ° rotation time is longer than the reference time, that is, when the software processing of the software processing unit 24 is completed within the 60 ° rotation time, the timer unit 26 generates an interrupt trigger signal with the 60 ° rotation time as a generation cycle. . In other words, an interrupt trigger signal is generated for each capture signal.

  On the other hand, when the motor 100 has a high rotation speed and the 60-degree rotation time is shorter than the reference time, that is, when the software process is not completed within the 60-degree rotation time, as shown in FIGS. An interrupt trigger signal is generated with the generation period as. Thus, since the timing for generating the interrupt trigger signal can be changed, it is possible to control up to a higher rotational speed without using a microcomputer having a high-performance CPU.

  In the present embodiment, an example in which the generation timing of the interrupt trigger signal is masked once is shown. However, the number of masks is not limited to one. For example, it may be twice. In this case, an interrupt trigger signal is generated with a 180 ° rotation time as a generation cycle.

(Second Embodiment)
In this embodiment, the description of the parts common to the motor control device 10 shown in the above embodiment is omitted.

  The feature of this embodiment is that the software processing unit 24 outputs a processing end timing signal of the software processing. Then, as shown in FIG. 7, the timer unit 26 calculates the software processing time in the software processing unit 24 based on the processing end timing signal, and uses the 60-degree rotation time and the software processing time to generate an interrupt trigger signal. Is to determine the generation timing.

  As shown in FIG. 7, the timer unit 26 includes a capture control unit 30, a timer counter 31, and a time comparison control unit 32. The capture control unit 30 generates a 60-degree rotation time from the timer count value of the timer counter 31 as in the first embodiment. Further, the software processing time in the software processing unit 24 is calculated based on the processing end timing signal and the interrupt trigger signal.

  As shown in FIG. 8, the time comparison control unit 32 includes a time comparator 40, a NOT gate 41, an interrupt mask control unit 42, an OR gate 43, and a storage unit 44. The time comparator 40 compares the difference between the 60 ° rotation time and the software processing time calculated by the capture control unit 30 (soft processing time−60 ° rotation time) with the threshold value read from the storage unit 44, and the difference When is larger than the threshold, “1” is output. On the other hand, when the difference is smaller than the threshold, “0” is output. This determination signal is input to the OR gate 43 and also input to the interrupt mask control unit 42 via the NOT gate 41. As the threshold value, a margin for the software processing time of the software processing unit 24 is set.

  When “1” is output from the time comparator 40, “0” is input to the interrupt mask control unit 42, and the interrupt mask control unit 42 outputs “0” to the OR gate 43. Therefore, “1” is output from the OR gate 43, that is, the timer unit 26. That is, an interrupt trigger signal is generated and output.

  On the other hand, when “0” is output from the time comparator 40, “1” is input to the interrupt mask control unit 42. The interrupt mask control unit 42 accumulates the input signal and outputs 1 when the value exceeds 1. That is, when “1” is input for the first time, the accumulated value is “1”, and “0” is output from the interrupt mask control unit 42. Therefore, both inputs to the OR gate 43 are “0”, and “0” is output from the OR gate 43 (timer unit 26). That is, no interrupt trigger signal is generated. When “2” is input for the second time, the accumulated value is “2” and exceeds 1, and therefore “1” is output from the interrupt mask control unit 42. Therefore, “1” is output from the OR gate 43 (timer unit 26). That is, an interrupt trigger signal is generated and output. Further, the interrupt mask control unit 42 resets the accumulated value when “0” is input or the accumulated value becomes “2” and “1” is output. In other words, when “1” is output from the OR gate 43, that is, when the interrupt trigger gate signal is output, the accumulated value is reset.

  As described above, in this embodiment, when the difference between the software processing time and the 60-degree rotation time is larger than the threshold value, the interrupt trigger signal is generated using the 60-degree rotation time as a generation cycle. When the difference becomes smaller than the threshold value, the interrupt trigger signal generation timing is masked once, and the interrupt trigger signal is generated with the 120 ° rotation time as the generation cycle.

  In addition, the interrupt mask control unit 42 outputs “1” and also outputs a mask signal indicating that the masking has been performed once to the software processing unit 24. Therefore, when the mask signal is input, the software processing unit 24 calculates the rotation speed as 120-degree rotation time.

  Next, processing executed in PWM output will be described with reference to FIG. The processing in the present embodiment is substantially the same as the processing shown in the first embodiment (see FIG. 5), so only the differences will be described.

  Steps S20 to S23 are the same as steps S10 to S13 shown in the first embodiment. Following step S23, the timer unit 26 calculates the software processing time of the software processing unit 24 based on the processing end timing signal as described above (step S24). Then, the difference between the software processing time and the 60-degree rotation time is compared with the threshold value (step S25). As a result, if the difference is larger than the threshold, an interrupt trigger signal is generated (step S27).

  On the other hand, if the difference is smaller than the threshold value in step S25, it is determined whether or not the above-described accumulated value is larger than 1 (step S26). That is, it is determined whether or not the mask for generating the interrupt trigger signal is the first time. In step S26, only when the accumulated value is “1”, that is, when the mask is the first time, the process returns to step 20, and steps S20 to S25 are repeated. If the 60-degree rotation time is longer than the reference time in step S25, an interrupt trigger signal is generated (step S27). In this case, an interrupt trigger signal is generated with a 120-degree rotation time as a generation cycle. In step S26, an interrupt trigger signal is also generated when the accumulated value is “2” (step S27). In this case as well, an interrupt trigger signal is generated with a 120-degree rotation time as a generation cycle.

  Since Step 28 to Step 30 are the same as Step S17 to Step S19 shown in the first embodiment, description thereof will be omitted.

  Next, the effect of the characteristic part of the motor control apparatus 10 according to the present embodiment will be described.

  When the difference is larger than the threshold value, that is, when the software processing of the software processing unit 24 ends within the 60-degree rotation time, the timer unit 26 generates an interrupt trigger signal with the 60-degree rotation time as a generation cycle. In other words, an interrupt trigger signal is generated for each capture signal.

  On the other hand, when the motor 100 is at a high rotation speed and the difference is smaller than the threshold value, that is, when the software process is not completed within the 60-degree rotation time, as shown in FIG. Is generated. Thus, since the timing for generating the interrupt trigger signal can be changed, it is possible to control up to a higher rotational speed without using a microcomputer having a high-performance CPU.

  Also in this embodiment, an example in which the generation timing of the interrupt trigger signal is masked once is shown. However, the number of masks is not limited to one. For example, it may be twice. In this case, an interrupt trigger signal is generated with a 180 ° rotation time as a generation cycle.

  In addition, an example in which the margin for the software processing time of the software processing unit 24 is set as a threshold is shown. However, for example, 10% of the 60-degree rotation time immediately before the 60-degree rotation time for obtaining the difference may be set as the threshold value.

(Third embodiment)
In this embodiment, the description of the parts common to the motor control device 10 shown in the above embodiment is omitted.

  A feature of the present embodiment is that a status signal indicating whether the software processing unit 24 is executing a software process or is waiting until the software process ends and the next software process is executed. Output. The timer unit 26 is to generate an interrupt trigger signal when a capture signal is input in a state in which a state signal indicating standby is input.

  As shown in FIG. 11, the timer unit 26 includes an AND gate 34 and a mask number counting unit 35. The AND gate 34 receives a capture signal and a status signal. As the status signal, “0” is input during execution of software processing, and “1” is input during standby. Therefore, when a capture signal is input during standby, the AND gate 34 generates and outputs “1”, that is, an interrupt trigger signal.

  A state signal and a capture signal are input to the mask number counting unit 35. The mask number counting unit 35 counts how many times the capture signal is input after the state signal becomes “0”. Since this count value is the number of masks for which an interrupt trigger signal was not generated even though a capture signal was input, this count value is output to the software processing unit 24 as a mask signal. The software processing unit 24 calculates the rotation speed based on the interrupt trigger signal and the mask signal. The count value is reset when “1” is input to the mask number counting unit 35, that is, when a status signal indicating standby is input.

  Next, processing executed in PWM output will be described with reference to FIG. The processing in the present embodiment will not be described for the same parts as the processing shown in the first embodiment.

  Steps S40 to S42 are the same as steps S10 to S12 shown in the first embodiment. Next, in step S43, the signal “1” indicating standby is input as a status signal to the AND gate 34 constituting the timer unit 26, and further, a capture signal is input to the AND gate 34 in step S44. The timer unit 26 (AND gate 34) generates and outputs an interrupt trigger signal only when it is detected.

  In step S43, when the status signal is a signal “0” indicating that the software process is being performed, the process returns to step S40 in order to mask the generation of the interrupt trigger signal. In step S44, if no capture signal is input even though a signal indicating standby is input, the process returns to step S43.

  Steps S46 and S47 are the same as steps S18 and S19 shown in the first embodiment, and thus description thereof is omitted.

  Next, the effect of the characteristic part of the motor control apparatus 10 according to the present embodiment will be described.

  As shown in FIG. 13, the timer unit 26 of the present embodiment generates an interrupt trigger signal when a capture signal is input in a state where a state signal indicating standby is input. On the other hand, in a state where a state signal indicating that soft processing is in progress, an interrupt trigger signal is not generated even if a capture signal is input. According to this, when the software process ends within the 60-degree rotation time, the interrupt trigger signal can be generated with the 60-degree rotation time as a generation cycle. On the other hand, when the motor 100 becomes a high rotation and the software processing is not completed within the 60-degree rotation time, a time corresponding to n times a predetermined electrical angle (n is an integer of 2 or more) is generated according to the software processing time. An interrupt trigger signal can be generated. Thus, since the timing for generating the interrupt trigger signal can be changed, it is possible to control up to a higher rotational speed without using a microcomputer having a high-performance CPU.

  In particular, according to the present embodiment, since the number of masks is not limited, the timing (in other words, the generation cycle) for generating the interrupt trigger signal can be changed according to the number of rotations of the motor 100.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 10 ... Motor control apparatus, 11 ... Hall element (position detection means), 12 ... Microcomputer, 20 ... CPU, 21 ... ROM, 22 ... RAM, 23 ... Motor Control circuit, 24... Software processing unit (calculation unit), 25... Position detection unit, 26... Timer unit, 27... PWM output unit, 30. Timer counter 32... Time comparison control unit 33... Storage unit 34... AND gate 35. Mask number counting unit 40 40 Time comparator 41. 42 ... Interrupt mask control unit, 43 ... OR gate, 44 ... Storage unit, 100 ... Motor, 100a ... Rotor, 100b ... Stator, 101 ... Gate driver, 102 ..Inverters

Claims (4)

A motor control device that PWM-controls a motor (100) including a rotor (100a) and a stator provided with a multiphase winding,
Position detecting means (11) for outputting a rotational position signal of the rotor;
A position detector (25) that generates a capture signal each time the rotor rotates by a predetermined electrical angle based on the rotational position signal;
A timer unit (26) for generating an interrupt trigger signal at a timing determined based on the capture signal;
A calculation unit (24) for executing an interrupt process by the interrupt trigger signal and calculating a PWM duty;
A PWM output unit (27) for outputting a PWM signal based on the calculated PWM duty,
When the interrupt process in the arithmetic unit does not end within the time corresponding to the predetermined electrical angle, the timer unit has a generation cycle of the interrupt trigger signal that is n times the predetermined electrical angle (n is 2 or more). A motor control device having a function of changing a timing for generating the interrupt trigger signal so that a time corresponding to an integer) is reached. The timer unit is
Based on the capture signal, the rotation time required to rotate the predetermined electrical angle is calculated, and the calculated rotation time is compared with a reference time set in advance according to the interrupt processing time of the arithmetic unit. ,
When the rotation time is longer than the reference time, the interrupt trigger signal is generated so that the generation period is a time corresponding to the predetermined electrical angle,
When the rotation time is shorter than the reference time, the interrupt trigger signal is generated so that the generation cycle is a time corresponding to n times the predetermined electrical angle (n is an integer of 2 or more). The motor control device according to claim 1, wherein The arithmetic unit outputs a process end timing signal at the end of the interrupt process,
The timer unit is
Based on the capture signal, a rotation time required to rotate the predetermined electrical angle is calculated, and on the basis of the processing end timing signal, an interruption processing time in the calculation unit is calculated, and the rotation time and the rotation time are calculated. Compare with interrupt processing time,
When the difference between the interrupt processing time and the rotation time is greater than a preset threshold, the interrupt trigger signal is generated so that the generation period is a time corresponding to the predetermined electrical angle,
When the difference is smaller than the threshold, the interrupt trigger signal is generated so that the generation period is a time corresponding to n times the predetermined electrical angle (n is an integer of 2 or more). The motor control device according to claim 1. The arithmetic unit outputs a status signal indicating whether the interrupt process is being executed, and whether the interrupt process is completed and waiting until the next interrupt process is executed,
The timer unit is
The motor control device according to claim 1, wherein the interrupt trigger signal is generated when the capture signal is input in a state where the state signal indicating standby is input.

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