JP2006034070A - Method and device for controlling motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress the occurrence of beat, and to control a rotational speed of a motor. <P>SOLUTION: A control unit 1a of the motor comprises a skip operation section 11 that is a rotational speed command value updating section, a speed control unit 12, an adder/subtractor 121, an arithmetic section 13, and a motor control unit 7. The arithmetic section 13 obtains a prescribed value m×f<SB>T</SB>/n(=f<SB>m10</SB>). The skip operation section 11 uses a given prescribed value f<SB>m10</SB>as a reference, obtains prescribed ranges f<SB>beat-</SB>, f<SB>beat+</SB>before and after it as the range of the rotational speed for causing a beat, performs comparison with the given rotation speed command value f<SB>m1</SB><SP>*</SP>, and outputs a new rotational speed command value f<SB>m</SB><SP>*</SP>. The adder/subtractor 121 subtracts the rotational speed f<SB>m</SB>from the rotational speed command value f<SB>m</SB><SP>*</SP>, thus obtaining a deviation Δf<SB>m</SB><SP>*</SP>. The speed control section 12 obtains a command value T<SP>*</SP>of torque applied to the motor, based on the deviation Δf<SB>m</SB><SP>*</SP>. The motor control section 7 controls an invertor 42, based on the command value T<SP>*</SP>of the torque, thus applying desired torque to the motor 2 for leading to a desired rotational speed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a motor control method and a motor control device, and can be applied to, for example, an air conditioner.

  The motor is provided, for example, in an air conditioner or the like, and rotates by applying torque. Torque is generated by the current supplied to the motor. Therefore, for example, the rotation of the motor is controlled by supplying a desired current to the motor by controlling the inverter.

  In addition, the technique relevant to this invention is shown below. Patent Document 1 discloses an inverter control technique that improves the waveform of an input current by causing a torque to pulsate at a frequency twice the power supply frequency.

JP 2002-51589 A

  However, when the motor rotates, a sound including a component having a frequency that is an integral multiple of the rotation speed and a component having a frequency that is an integral multiple of the pulsation frequency of the torque applied to the motor is generated from the motor. . At this time, the beat caused by the beat frequency, which is the difference between the frequency that is an integral multiple of the rotational speed and the frequency that is an integral multiple of the pulsation frequency of the torque, occurred. For example, even in the technique disclosed in Patent Document 1, there is a possibility that a beat is generated from the motor.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to control the rotation speed of a motor while suppressing the occurrence of beats.

In the motor control method according to claim 1 of the present invention, when the motor (2) is rotated by applying torque, the rotation speed (f _m ) of the motor is beaten in the rotation sound of the motor. If the rotation speed is within the range (f _{beat +} , f _beat− ), the rotation speed is substantially matched with the boundary value (f _m10 , f _m11 , f _m12 ) of the range.

A motor control method according to a second aspect of the present invention is the motor control method according to the first aspect, wherein (a) a rotational speed command value (f _m1 ^* ) which is a command value of the rotational speed (f _m ) ^. ) And (b) if the rotational speed command value is within the range, the boundary values (f _m10 , f _m11 , f _m12 ) are set as the new rotational speed command value (f _m ^* ). And (c) controlling the rotational speed so that there is no difference (Δf _m ^* ) from the rotational speed command value updated in step (b).

A motor control method according to a third aspect of the present invention is the motor control method according to the first or second aspect, wherein the first frequency is a first integer (n) times the rotational speed (f _m ). (N · f _m ) and a predetermined value (m of the rotation speed) at which the second frequency (m · f _T ) approximately equal to the second integer (m) times the pulsation frequency (f _T ) at which the torque pulsates F _T / n = f _m10 ), the range has one of the boundary values, and the rotational speed is changed to the predetermined value.

A motor control method according to a fourth aspect of the present invention is the motor control method according to the second aspect, wherein the first frequency (n · f) is a first integer (n) times the rotation speed (f _m ). _m ) and a predetermined value (m · f _T / _M ) of the rotational speed at which the second frequency (m · f _T ) approximately equal to the second integer (m) times the pulsation frequency (f _T ) at which the torque pulsates n = f _m10 ) as the boundary value, and the predetermined value is updated as the new rotation speed command value (f _m2 ^* ) in the step (b).

A motor control method according to a fifth aspect of the present invention is the motor control method according to the fourth aspect, wherein the step (c) includes (c-1) the rotation speed (f _m ) and the predetermined value. The rotation speed command value (f _m2 ^* ) updated in the step (b) is further updated so that the difference (Δf _m ) from (m · f _T / n) is eliminated, and this is updated with the new rotation. The rotational speed so that there is no difference (Δf _m ^* ) between the step of setting the speed command value (f _m3 ^* ) and (c-2) the rotation speed command value updated in step (c-1). And a step of controlling.

A motor control method according to a sixth aspect of the present invention is the motor control method according to the fourth aspect, wherein the step (c) includes (c-1) a phase (θ _m ) of the motor (2). Detecting the first phase (n · θ _m ) by multiplying it by the first integer (n), and (c-2) detecting the phase (θ _T ) at which the torque pulsates, Multiplying the second integer (m) by the second phase (m · θ _T ), and (c-3) eliminating the difference (Δθ _m ) between the first phase and the second phase. , Further updating the rotational speed command value (f _m2 ^* ) updated in the step (b) to make this a new rotational speed command value (f _m4 ^* ), (c-4) The rotational speed is controlled so that there is no difference (Δf _m ^* ) from the rotational speed command value updated in step (c-3). Step.

A motor control method according to a seventh aspect of the present invention is the motor control method according to any one of the third to sixth aspects, wherein the pulsation frequency is applied to the motor (2) by the torque. Is twice the frequency of the AC voltage (V _ac ) provided to apply.

The motor control device according to claim 8 of the present invention is a control device that controls the rotational speed (f _m ) of the motor (2) based on the rotational speed command value (f _m1 ^* ) that is the command value. If the rotation speed command value is within the rotation speed range (f _{beat +} , f _beat- ) where the rotation sound of the motor is generated, the rotation speed command value is set to a boundary value (f It comprises a _{15); m10, f m11,} f m12; f m10; rotational speed command value update unit for changing the f _m10) (11; 14.

A motor control apparatus according to a ninth aspect of the present invention is the motor control apparatus according to the eighth aspect, further comprising a speed control unit (12), wherein the speed control unit is configured to update the rotational speed command value update unit. The rotational speed is controlled based on a deviation (Δf _m ^* ) between the rotational speed command value (f _m ^* ) obtained from (11) and the rotational speed (f _m ).

A motor control apparatus according to a tenth aspect of the present invention is the motor control apparatus according to the eighth aspect, further comprising a first calculation section (13), wherein the first integer (the rotation speed (f _m )) n) times the first frequency (n · f _m ) and the second frequency (m · f _T ) substantially equal to the second integer (m) times the pulsation frequency (f _T ) at which the torque pulsates. A predetermined value (m · f _T / n = f _m10 ) of the rotation speed is included as one of the boundary values in the range, the first calculation unit obtains the predetermined value, and the rotation speed command value update unit (11; 14; 15) adopts the predetermined value as the boundary value at which the rotation speed command value is changed.

A motor control device according to an eleventh aspect of the present invention is the motor control device according to the tenth aspect, further comprising a speed control unit (12), wherein the speed control unit is configured to update the rotational speed command value update unit. The rotational speed is controlled based on a deviation (Δf _m ^* ) between the rotational speed command value (f _m ^* ) obtained from (11) and the rotational speed (f _m ).

A motor control apparatus according to a twelfth aspect of the present invention is the motor control apparatus according to the tenth aspect, further comprising a speed control section (12), wherein the rotational speed command value updating section (14) is changed. A skip operation unit (141) for outputting the predetermined value (m · f _T / n = f _m10 = f _m2 ^* ) when the previous rotation speed command value (f _m1 ^* ) is within the range; a predetermined value and the rotational speed (f _m) and the new speed command value in order to deviation (Delta] f _m) is converged to zero (f _m3 ^*) deviation converging unit for generating the (142), the The speed control unit controls the rotation speed based on a deviation (Δf _m ^* ) between the rotation speed command value obtained from the deviation convergence unit and the rotation speed (f _m ).

A motor control device according to a thirteenth aspect of the present invention is the motor control device according to the tenth aspect, further comprising a speed control unit (12), wherein the rotational speed command value update unit (15) is changed. A skip operation unit (151) for outputting the predetermined value (m · f _T / n = f _m10 = f _m2 ^* ) when the previous rotation speed command value (f _m1 ^* ) is within the range; A second operation unit (155) for obtaining a first phase (n · θ _m ) by multiplying the phase (θ _m ) of the motor (2) by the first integer (n); and a phase (θ _T ) at which the torque pulsates ) Is multiplied by the second integer (m) to obtain the second phase (m · θ _T ), and the deviation (Δθ _m ) between the first phase and the second phase is zero. and a deviation converging unit for generating (153) a new speed command value (f _m4 ^*) to converge to, the speed control unit, Controlling the rotational speed based on the said rotational speed command values obtained from serial deviation converging portion rotational speed (f _m) and deviation (Δf _m ^*).

A motor control device according to a fourteenth aspect of the present invention is the motor control device according to any one of the tenth to thirteenth aspects, wherein the pulsation frequency (f _T ) is the motor ( It is twice the frequency of the AC voltage (V _ac ) provided to apply the torque to 2).

  A motor control device according to a fifteenth aspect of the present invention is the motor control device according to any one of the eighth to fourteenth aspects, further comprising a voltage conversion unit (4), and the voltage conversion unit. AC voltage is supplied to the unit, and the voltage conversion unit rectifies the AC voltage and outputs a DC voltage, an inverter (42) that converts the DC voltage into a desired AC voltage, And a capacitor (C) that bypasses harmonics generated by switching of the inverter.

  According to the motor control method of the first aspect of the present invention or the motor control apparatus of the eighth aspect of the present invention, the rotational speed of the motor is controlled to a boundary value within a range in which the beat occurs, so that the rotational speed is made significantly different. Eliminate the beat without it.

  According to the motor control method of the second aspect of the present invention, the rotational speed is changed to the boundary value of the range in which the beat occurs by controlling the rotational speed with the rotational speed command value according to steps (a) to (c). Is done. Therefore, the occurrence of beat is accurately suppressed.

  According to the motor control method according to claim 3 or claim 4 of the present invention or the motor control device according to claim 10, the first frequency and the second frequency substantially coincide with each other. Noise is reduced.

  According to the motor control method of the present invention or the motor control device of the twelfth aspect of the present invention, the error between the rotational speed command value and the rotational speed obtained in step (b) or the skip operation unit is reduced. Therefore, the occurrence of beat is suppressed with higher accuracy.

  In the motor control method according to the sixth aspect of the present invention or the motor control apparatus according to the thirteenth aspect, since the first phase and the second phase are synchronized, the step (b) or the skip operation unit is obtained. The error between the rotational speed command value and the rotational speed is reduced. Therefore, the occurrence of beat is suppressed with higher accuracy.

  The motor control method according to the seventh aspect of the present invention or the motor control apparatus according to the fourteenth aspect of the present invention is applied, for example, when the capacity of the smoothing capacitor included in the voltage conversion unit that supplies a desired voltage to the motor is small. The

  According to the motor control device of the ninth or eleventh aspect of the present invention, the rotational speed command value and the rotational speed can be made to coincide with each other with high accuracy.

  According to the motor control device of a fifteenth aspect of the present invention, even if the smoothing capacitor has a small capacity and a beat is likely to occur, the control unit according to any one of the eighth to fourteenth aspects may be used. The beating is resolved.

  The controlled object 10 and the drive power supply 3 controlled by the motor control device according to the present invention are shown in FIGS. 3, 12, and 13, respectively.

The drive power supply 3 generates an alternating voltage V _ac and supplies it to the voltage converter 4.

The control target 10 includes a motor 2 and a voltage conversion unit 4. The voltage conversion unit 4 includes a converter 41, a capacitor C, and an inverter 42, and converts the AC voltage V _ac into desired three-phase AC voltages V _u , V _v , and V _w .

Converter 41 includes diodes 411 to 414. The diodes 411 and 412 are connected in series between the output terminals N3 and N4 of the converter 41 via the connection point N1. At this time, the diodes 411 and 412 are arranged such that current flows from the output end N4 side to the output end N3 side, respectively. The diodes 413 and 414 are connected in series between the output terminals N3 and N4 via the connection point N2. At this time, the diodes 413 and 414 are arranged such that current flows from the output end N4 side to the output end N3 side, respectively. The connection points N1 and N2 are connected to the drive power source 3 and input with the AC voltage V _ac .

  The capacitor C is connected between the output terminals N3 and N4.

  The inverter 42 includes IGBT (Insulated Gate Bipolar Transistor) modules 421 to 426. Each of the IGBT modules 421 to 426 includes an IGBT and a diode, and the diode is connected between the emitter terminal and the collector terminal of the IGBT. At this time, the diode is arranged so that a current flows from the emitter terminal side to the collector terminal side.

  The IGBT module 421 has an emitter terminal connected to the collector terminal of the IGBT module 422 via the connection point N5, and a collector terminal connected to the input terminal N3 of the inverter 42. The IGBT module 422 has an emitter terminal connected to the input terminal N4 of the inverter 42. Here, the output terminals N3 and N4 of the converter 41 are grasped as the input terminals of the inverter 42. The connection point N5 is connected to the motor 2.

  The IGBT module 423 has an emitter terminal connected to the collector terminal of the IGBT module 424 via the connection point N6, and a collector terminal connected to the input terminal N3. The IGBT module 424 has an emitter terminal connected to the input terminal N4. The IGBT module 425 has an emitter terminal connected to the collector terminal of the IGBT module 426 via the connection point N7, and a collector terminal connected to the input terminal N3. The IGBT module 426 has an emitter terminal connected to the input terminal N4. Connection points N6 and N7 are connected to the motor 2, respectively.

Converter 41 rectifies AC voltage V _ac supplied from drive power supply 3 and outputs DC voltage V _dc between output terminals N3 and N4.

The inverter 42 converts the DC voltage V _dc input to the input terminals N3 and N4 into desired three-phase AC voltages V _u , V _v and V _w . At this time, the capacitor C bypasses the harmonics generated by the switching of the inverter 42. AC voltages V _u , V _v , V _w are input to the motor 2, and torque is applied to the motor 2 by three-phase currents I _u , I _v , I _{w that} flow according to the AC voltages V _u , V _v , V _w. .

In the control object 10 described above, pulsation is likely to be included in the DC voltage V _dc . In particular, when the capacitance of the capacitor C is small, the pulsation becomes significant. When the DC voltage V _dc includes pulsation, the torque applied to the motor 2 also pulsates. This content is disclosed in Patent Document 1, for example.

Therefore, when the motor 2 torque is applied to rotate, and an integer n times the frequency n · f _m of the rotational speed f _m of the motor 2, integral m multiple of the frequency m of the pulsation frequency f _T which torque pulsates the absolute value of the difference between the _{· f T | n · f m} -m · f T | beat due to the beat frequency which is expressed by results from the motor 2. However, the beat frequency is 0 (Hz), that is, the frequency n · f _m and the frequency m · f _T substantially matches _{| n · f m -m · f} T | when = 0, the beat does not occur.

FIG. 1 is a diagram conceptually showing the range of the rotational speed f _m at which beat occurs. When the rotational speed f _m is a predetermined value m · f _T / n (= f _m10 ), that is, when | n · f _m −m · f _T | = 0 is satisfied, no beat occurs.

On the other hand, _{beats occur in} the predetermined ranges f _beat− and f _{beat +} around the predetermined value m · f _T / n. Here, the predetermined range f _beat− is in the range of f _m12 <f _beat− <f _m10 , and the predetermined range f _{beat +} is in the range of f _m10 <f _{beat +} <f _m11 . _Further, the lower limit value f _m12 of the predetermined range f _{beat− and} the upper limit value f _m11 of the predetermined range f _{beat +} are rotational speeds at which beat is eliminated before and after the predetermined value f _m10 .

The predetermined value f _m10 is obtained in advance. The predetermined range f _Beat- width Delta] f of _beat- (= f _m10 -f _m12) and a predetermined range f _{beat +} width _{Δf beat + (= f m11 -f} m10) is set in advance. The predetermined value f _m10 and the widths Δf _beat− and Δf _{beat +} may be obtained by calculation or may be obtained by actual detection.

In FIG. 2, the predetermined value f _m10 is specifically illustrated. That is, when the combination of integers m and n is (m, n) = (1,3), (1,2), (3,4), (1,1), (3,2), The predetermined values f _m10 (Hz) are obtained as 33.3, 50, 75, 100, and 150, respectively. Here, the pulsation frequency f _T is set to 100 (Hz).

  In the following embodiments, techniques for eliminating beating will be described using the above-described range of rotation speed at which beating occurs.

First embodiment.
FIG. 3 is a block diagram conceptually showing the motor control apparatus 1a according to the present embodiment. The motor control device 1a includes a skip operation unit 11, a speed control unit 12, an adder / subtractor 121, a calculation unit 13, a pulsation frequency calculation unit 5, a rotation speed calculation unit 6, and a motor control unit 7 which are rotation speed command value update units. Prepare.

In the controlled object 10, especially when the capacity of the capacitor C is small, the pulse frequency f _T which pulsation of torque has twice the frequency f _in of the AC voltage V _ac.

The pulsation frequency calculation unit 5 includes calculation units 51 and 52. The computing unit 52 obtains the frequency f _in of the AC voltage V _ac by, for example, time-differentiating the phase θ _in of the AC voltage V _ac detected from the drive power supply 3. Calculation unit 51 obtains the pulse frequency f _T and doubling the frequency f _in. The pulsation frequency f _T is given to the calculation unit 13.

The calculation unit 13 multiplies the pulsation frequency f _T by a value m / n obtained by dividing the integer m by the integer n to obtain a predetermined value m · f _T / n (= f _m10 ). The predetermined value f _m10 is given to the skip operation unit 11.

The skip operation unit 11 stores, for example, the widths Δf _beat− and Δf _{beat +} of the predetermined ranges f _beat− and f _{beat +} , and the predetermined range f _beat− before and after the given value f _m10 is used as a reference. , F _{beat +} is determined as the range of rotation speed at which the beat occurs.

The skip operation unit 11, the rotation speed f rotational speed command value is a command value _m f _m1 ^* is further provided. The skip operation unit 11 outputs a new rotation speed command value f _m ^* to be described later by comparing this with the rotation speed ranges f _beat− and f _{beat +} . The new rotation speed command value f _m ^* is given to the adder / subtractor 121.

FIG. 4 conceptually shows the operation of the skip operation unit 11 in a flowchart. In step 101, if the rotational speed command value f _m1 ^* is determined to be _{m · f T / n-Δf} beat- (= f m12) below, the rotation speed command value f _m1 ^* of step 103 The value is directly used as a new rotation speed command value f _m ^* .

If it is determined in step 101 that the rotational speed command value f _m1 ^* is larger than m · f _T / n−Δf _beat− , it is further determined in step 102.

If it is determined in step 102 that the rotational speed command value f _m1 ^* is greater than or equal to m · f _T / n + Δf _{beat +} (= f _m11 ), the value of the rotational speed command value f _m1 ^* remains unchanged in step 104. A new rotation speed command value f _m ^* is set.

If it is determined in step 102 that the rotational speed command value f _m1 ^* is smaller than m · f _T / n + Δf _{beat +,} m · f _T / n−Δf _beat− is determined as a new rotational speed command in step 105. Updated as the value f _m ^* .

FIG. 5 shows the above-described content in the relationship between the input f _m1 ^* and the output f _m ^* in the skip operation unit 11. In FIG. 5, when the rotational speed command value f _m1 ^* is within the ranges f _beat− and f _{beat +} , the skip operation unit 11 _sets the lower limit value f _m12 of the range f _{beat− as} the boundary value to a new rotation. Update and output as speed command value f _m ^* . When the rotational speed command value f _m1 ^* is outside the ranges f _beat− and f _{beat +} , the value as it is is output as the rotational speed command value f _m ^* .

When the rotational speed command value f _m1 ^* matches a predetermined value f _m10 may output the raw values as the rotational speed command value f _m ^*, the range f _Beat- lower limit value f _m12 or range f The upper limit value f _m11 of _{beat +} may be output as a new rotation speed command value f _m ^* . 4 and 5, the lower limit value f _m12 of the range f _beat− is output as a new rotation speed command value f _m ^* .

FIG. 6 conceptually shows an operation of the skip operation unit 11 different from FIG. 4 by a flowchart. In step 105 shown in FIG. 6, m · f _T / n + Δf _{beat +} is updated as a new rotation speed command value f _m ^* . The other steps 101 to 104 are the same as steps 101 to 104 shown in FIG.

FIG. 7 shows the above-described content in the relationship between the input f _m1 ^* and the output f _m ^* in the skip operation unit 11. In FIG. 7, when the rotational speed command value f _m1 ^* is within the ranges f _beat− and f _{beat +} , the skip operation unit 11 sets the upper limit value f _m11 of the range f _{beat +} as the new rotational speed command. Update and output as value f _m ^* . When the rotational speed command value f _m1 ^* is outside the ranges f _beat− and f _{beat +} , the value as it is is output as the rotational speed command value f _m ^* .

FIG. 8 conceptually shows the operation of the skip operation unit 11 different from those in FIGS. 4 and 6 by a flowchart. Steps 101 to 104 are the same as steps 101 to 104 shown in FIG. If it is determined in step 102 that the rotational speed command value f _m1 ^* is smaller than m · f _T / n + Δf _{beat +} , it is further determined in step 106.

If it is determined in step 106 that the rotational speed command value f _m1 ^* is greater than or equal to m · f _T / n (= f _m10 ), then in step 107 m · f _T / n + Δf _{beat +} becomes the new rotational speed. It is updated as the command value f _m ^* .

When it is determined in step 106 that the rotational speed command value f _m1 ^* is smaller than m · f _T / n, in step 108, m · f _T / n−Δf _beat− is a new rotational speed command value. Updated as f _m ^* .

FIG. 9 shows the above-described contents in relation to the input f _m1 ^* and the output f _m ^* in the skip operation unit 11. In FIG. 9, when the rotational speed command value f _m1 ^* is within the range f _beat− , the skip operation unit 11 _sets the lower limit value f _m12 of the range f _beat− as the new rotational speed command value f. update output as _m ^*, when the rotational speed command value f _m1 ^* is in the range f _{beat +} a is a range f _{beat +} upper limit f new rotational speed command values _m11 f _m ^* is a boundary value Update and output. When the rotational speed command value f _m1 ^* is outside the ranges f _beat− and f _{beat +} , the value as it is is output as the rotational speed command value f _m ^* .

In any of FIGS. 6, 7, 8, and 9 described above, when the rotational speed command value f _m1 ^* coincides with the predetermined value f _m10 , the upper limit value f _m11 of the range f _{beat +} is a new rotational speed. It is output as a command value f _m ^* . However, if the rotational speed command value f _m1 ^* matches the predetermined value f _m10 , the value as it is may be output as the rotational speed command value f _m ^* , or the lower limit value f _m12 of the range f _beat- it may be output as a new speed command value f _m ^*.

Returning to FIG. 3, the rotational speed calculation unit 6 obtains the rotational speed f _m of the motor 2 by, for example, time-differentiating the phase θ _m of the motor 2 detected from the motor 2. The rotation speed f _m is given to the adder / subtractor 121.

The adder / subtractor 121 obtains the deviation Δf _m ^* by subtracting the rotation speed f _m from the rotation speed command value f _m ^* . The deviation Δf _m ^* is given to the speed control unit 12.

The speed control unit 12 obtains a command value T ^{* of the} torque to be applied to the motor, for example, by performing PI calculation based on the deviation Δf _m ^* . The torque command value T ^* is given to the motor control unit 7.

The motor control unit 7 controls the inverter 42 based on the torque command value T ^* . As a result, a desired torque is applied to the motor 2 and led to a desired rotational speed.

That is, the difference Delta] f _m ^* as eliminates the rotational speed command value f _m ^* outputted from the step operation unit 11, the rotational speed f _m is controlled.

According to the motor control device 1a described above, the rotational speed f _m is remarkably increased because the rotation speed of the motor 2 is controlled to the boundary values f _m12 , f _m11 , and f _m10 of the range f _beat− and f _{beat + in which} the _beat occurs. Eliminate beating without making it different.

In addition, by controlling the rotational speed f _m using the rotational speed command value f _m ^* , the rotational speed f _m is changed to the boundary values f _m12 , f _m11 , and f _m10 of the ranges f _beat− and f _{beat +} where the beat occurs. Is done. Therefore, the occurrence of beat is accurately suppressed.

In particular, according to the operation of the skip operation unit 11 shown in FIG. 8, differs significantly from that without the rotational speed command value f _m1 ^*, since the new rotational speed command value f _m ^* is output, the rotational speed f _m is This is desirable in that it does not differ significantly from the rotational speed command value f _m1 ^* .

Second embodiment.
In the present embodiment, the operation of the skip operation unit 11 shown in FIG. 1 is different from that of the first embodiment. Other operations are the same as those in the first embodiment.

FIG. 10 conceptually shows the operation of the skip operation unit 11 by a flowchart. In step 201, if the rotational speed command value f _m1 ^* is determined to be _{m · f T / n-Δf} beat- (= f m12) below, the rotation speed command value f _m1 ^* of step 203 The value is directly used as a new rotation speed command value f _m ^* .

If it is determined in step 201 that the rotational speed command value f _m1 ^* is larger than m · f _T / n−Δf _beat− (= f _m12 ), it is further determined in step 202.

If it is determined in step 202 that the rotation speed command value f _m1 ^* is equal to or greater than m · f _T / n + Δf _{beat +} (= f _m11 ), the value of the rotation speed command value f _m1 ^* is left as it is in step 204. A new rotation speed command value f _m ^* is set.

If it is determined in step 202 that the rotational speed command value f _m1 ^* is smaller than m · f _T / n + Δf _{beat +} (= f _m11 ), then in step 205 m · f _T / n (= f _m10 ) Is updated as a new rotation speed command value f _m ^* .

FIG. 11 shows the above-described contents in relation to the input f _m1 ^* and the output f _m ^* in the skip operation unit 11. That is, when the rotational speed command value f _m1 ^* is within the ranges f _beat− and f _{beat +} , the skip operation unit 11 uses the predetermined value m · f _T / n (= f _m10 ) as a new rotational speed command value. Update as f _m ^* and output. If the rotational speed command value f _m1 ^* matches the predetermined value f _m10 , it is output as it is. When the rotational speed command value f _m1 ^* is outside the ranges f _beat− and f _{beat +} , the value as it is is output as the rotational speed command value f _m ^* .

With such control technique, since the frequency n · f _m and the frequency m · f _T substantially coincides, the noise due to their beat frequency is reduced.

Third embodiment.
In the embodiment described above, by controlling so that the deviation Delta] f _m ^* is eliminated, thereby matching the rotational speed f _m of the rotational speed command value f _m ^*. However, it may be difficult to converge the deviation Δf _m ^* to 0 and make the rotational speed f _m coincide with the rotational speed command value f _m ^* .

In particular, for the second embodiment, when the rotational speed f _m does not match the rotational speed command value f _m ^* = f _m10 , the rotational speed f _m falls within the ranges f _beat− and f _{beat +} . And roar occurs.

Therefore, in the present embodiment, a technique for precisely matching the rotation speed f _m with the rotation speed command value f _m ^* = f _m10 will be described.

  FIG. 12 is a block diagram conceptually showing the motor control apparatus 1b according to the present embodiment. The motor control device 1b includes a rotation speed command value update unit 14 instead of the skip operation unit 11 shown in FIG. 12 that are the same as those shown in FIG. 1 are assigned the same reference numerals and operate in the same manner.

The rotation speed command value update unit 14 includes a skip operation unit 141 and a deviation convergence unit 142. The skip operation unit 141, the rotation speed command value is a command value speed f _m f _m1 ^* is given, provided further predetermined value m · f _T / n from the operation unit 13 (= f _m10) is. Then, similarly to the skip operation unit 11 described in the second embodiment, a rotation speed command value f _m2 ^* is output from the skip operation 141 (see FIG. 11). Here, a symbol f _m2 ^* is used in place of the symbol f _m ^* as a symbol representing the output rotation speed command value. The rotational speed command value f _m2 ^* is given to the deviation convergence unit 142, particularly an adder 1424 described later.

  The deviation convergence unit 142 includes an adder / subtractor 1421, a PI control unit 1422, a switching unit 1423, and an adder 1424.

The adder / subtractor 1421 is given a predetermined value m · f _T / n from the calculation unit 13 and a rotation speed f _m from the rotation speed calculation unit 6. The subtracter 1421 obtains the deviation Delta] f _m by subtracting the rotational speed f _m from a predetermined value m · f _T / n, be provided to the PI control unit 1423.

PI control unit 1422, by PI calculation on the basis of the deviation Delta] f _m, obtains a command value f _S1 ^* for converging the deviation Delta] f _m. The command value f _S1 ^* is obtained by, for example, the formula (1). Here, symbols K _P and K _I represent a proportional control gain and an integral control gain, respectively.

The switching unit 1423 is turned on when the predetermined value f _m10 is set to the rotation speed command value f _m2 ^* in the skip operation unit 141, and the value of the rotation speed command value f _m1 ^* is directly used as the rotation speed command value f _m2. When it is set to ^* , it is controlled off.

When the switching unit 1423 is controlled to be turned on, the command value f _S1 ^* output from the PI control unit 1422 is given to the adder 1424.

The adder 1424 obtains the sum of the rotation speed command value f _m2 ^* and the command value f _S1 ^* , updates this as a new rotation speed command value f _m3 ^* , and outputs it.

The adder / subtractor 121 obtains the deviation Δf _m ^* by subtracting the rotation speed f _m from the rotation speed command value f _m3 ^* . Hereinafter, based on the deviation Delta] f _m ^*, the rotation speed f _m is controlled in the same manner as described in the first embodiment.

According to the motor control device 1b described above, the effects described in the second embodiment can be obtained, and the error between the rotational speed command value f _m2 ^* and the rotational speed f _m becomes small, and therefore, the occurrence of beats. We suppress more accurately.

Fourth embodiment.
FIG. 13 is a block diagram conceptually showing the motor control apparatus 1c according to the present embodiment. The motor control device 1c includes a rotation speed command value update unit 15 instead of the skip operation unit 11 shown in FIG. Of the components shown in FIG. 13, the same components as those shown in FIG. 1 are given the same reference numerals and operate in the same manner.

The rotation speed command value update unit 15 includes a skip operation unit 151, a calculation unit 152, a deviation convergence unit 153, and a phase calculation unit 154. The skip operation unit 151 operates in the same manner as the skip operation unit 141 described in the third embodiment, and outputs a rotation speed command value f _m2 ^* (see FIG. 11). Here, a symbol f _m2 ^* is used in place of the symbol f _m ^* as a symbol representing the output rotation speed command value. The rotational speed command value f _m2 ^* is given to the deviation convergence unit 153, particularly an adder 1534 described later.

The phase calculator 154 is given the phase θ _in of the AC voltage V _ac detected from the drive power supply 3. Then, the phase calculation unit 154 obtains the pulsation phase θ _T based on the phase θ _in . Specifically, the pulsation frequency f _T with the torque ripple in the control object 10, since twice the frequency f _in of the AC voltage V _ac, the phase theta _T pulsations phase theta _in the AC voltage V _ac Is obtained by doubling the value.

The computing unit 152 multiplies the phase θ _T by an integer m to obtain the phase m · θ _T. The phase m · θ _T is given to the deviation convergence unit 153, particularly an adder / subtractor 1531 described later.

The computing unit 155 multiplies the phase θ _m by an integer n to obtain the phase n · θ _m . The phase n · θ _m is given to the adder / subtractor 1531 similarly to the phase m · θ _T.

  The deviation convergence unit 153 includes an adder / subtractor 1531, a PI control unit 1532, a switching unit 1533, and an adder 1534.

The adder / subtractor 1531 obtains a deviation Δθ _m by subtracting the phase n · θ _m from the phase m · θ _T , and gives this to the PI control unit 1533.

PI control unit 1532, by PI calculation on the basis of the deviation [Delta] [theta] _m, obtains the command value f _S2 ^* for converging the deviation [Delta] [theta] _m. The command value f _S2 ^* is obtained by, for example, equation (2). Here, symbols K _P and K _I represent a proportional control gain and an integral control gain, respectively.

The switching unit 1533 is controlled to be turned on when the predetermined value f _m10 is set to the rotation speed command value f _m2 ^* in the skip operation unit 151, and the value of the rotation speed command value f _m1 ^* is directly used as the rotation speed command value f _m2. When it is set to ^* , it is controlled off.

When switching unit 1533 is controlled to be on, command value f _S2 ^* output from PI control unit 1532 is provided to adder 1534.

The adder 1534 obtains the sum of the rotation speed command value f _m2 ^* and the command value f _S2 ^* , updates this as a new rotation speed command value f _m4 ^* , and outputs it.

The adder / subtractor 121 obtains the deviation Δf _m ^* by subtracting the rotation speed f _m from the rotation speed command value f _m4 ^* . Hereinafter, based on the deviation Δf _m ^* , the rotational speed is controlled in the same manner as described in the first embodiment.

According to the motor control device 1c described above, the effects described in the second embodiment can be obtained, and the phase m · θ _T and the phase n · θ _m are synchronized, so that the rotational speed command value f _m2 ^* And the rotation speed f _m are reduced. Therefore, the occurrence of beat is suppressed with higher accuracy.

It is a figure which shows notionally the range of the rotational speed which a beat produces. Is a diagram schematically showing an predetermined value _{m · f T / n (=} f m10). It is a block diagram which shows notionally the control apparatus of the motor demonstrated by 1st Embodiment. FIG. 6 is a flowchart conceptually showing the operation of a skip operation unit 11. Is a diagram conceptually illustrating the output f _m ^* relationship input f _m1 ^* and. FIG. 6 is a flowchart conceptually showing the operation of a skip operation unit 11. Is a diagram conceptually illustrating the output f _m ^* relationship input f _m1 ^* and. FIG. 6 is a flowchart conceptually showing the operation of a skip operation unit 11. Is a diagram conceptually illustrating the output f _m ^* relationship input f _m1 ^* and. It is a flowchart figure which shows notionally the operation | movement of the skip operation | movement part 11 demonstrated by 2nd Embodiment. Is a diagram conceptually illustrating the output f _m ^* relationship input f _m1 ^* and. It is a block diagram which shows notionally the control apparatus of the motor demonstrated by 3rd Embodiment. It is a block diagram which shows notionally the control apparatus of the motor demonstrated by 4th Embodiment.

Explanation of symbols

2 Motor f _m rotational speed _{f beat} +, f beat- range of the rotation speed f _m11, f _m12, f _m10 boundary value _{m · f T / n (=} f m10) predetermined value ^{_{f m *, f m1 *,}} f m2 * , F _m3 ^* , f _m4 ^* rotational speed command value n, m integer n · f _m , m · f _T frequency f _T pulsation frequency θ _m motor phase θ _T pulsation phase m · θ _T / n predetermined phase Δf _m ^* , Δf _m , Δθ _m deviation 11 Skip operation part (rotation speed command value update part)
14, 15 Rotational speed command value update unit 13, 152, 155 Calculation unit 12 Speed control unit 141, 151 Skip operation unit 142, 153 Deviation convergence unit 3 Drive power supply 4 Voltage conversion unit 41 Converter C capacitor 42 Inverter

Claims (15)

When rotating the motor (2) by applying a torque, the rotational speed of the motor (f _m) is the range of the rotational speed _{(f beat +,} f beat-) to beat the rotation noise of the motor is generated in the if any, the causes the rotational speed is substantially equal to the boundary value of the range _{(f m10, f m11, f} m12), a motor control method. (A) inputting the rotational speed rotational speed command value is a command value ^{_{(f m) (f m1 *}} ),
(B) If the rotation speed command value is within the range, _{updating the} boundary values (f _m10 , f _m11 , f _m12 ) as a new rotation speed command value (f _m ^* );
2. The motor control method according to claim 1, further comprising: (c) controlling the rotation speed so that a difference (Δf _m ^* ) from the rotation speed command value updated in the step (b) is eliminated. . A first frequency (n · f _m ) that is a first integer (n) times the rotational speed (f _m ) and a second frequency that is a second integer (m) times the pulsation frequency (f _T ) at which the torque pulsates. A predetermined value (m · f _T / n = f _m10 ) of the rotational speed at which (m · f _T ) substantially coincides with the range as one of the boundary values;
The motor control method according to claim 1, wherein the rotation speed is changed to the predetermined value. A first frequency (n · f _m ) that is a first integer (n) times the rotational speed (f _m ) and a second frequency that is a second integer (m) times the pulsation frequency (f _T ) at which the torque pulsates. A predetermined value (m · f _T / n = f _m10 ) of the rotational speed at which (m · f _T ) substantially coincides with the range as one of the boundary values;
The motor control method according to claim 2, wherein, in the step (b), the predetermined value is updated as a new rotation speed command value (f _m2 ^* ). The step (c)
(C-1) The rotational speed command value updated in step (b) so that the difference (Δf _m ) between the rotational speed (f _m ) and the predetermined value (m · f _T / n) is eliminated. Further updating (f _m2 ^* ) and setting it as a new rotational speed command value (f _m3 ^* );
(C-2) The step of controlling the rotational speed so as to eliminate a difference (Δf _m ^* ) from the rotational speed command value updated in the step (c-1) is performed. Motor control method. The step (c)
(C-1) detecting the phase (θ _m ) of the motor (2) and multiplying it by the first integer (n) to obtain the first phase (n · θ _m );
(C-2) detecting a phase (θ _T ) at which the torque pulsates and multiplying the phase by the second integer (m) to obtain a second phase (m · θ _T );
(C-3) Further updating the rotational speed command value (f _m2 ^* ) updated in step (b) so that the difference (Δθ _m ) between the first phase and the second phase is eliminated. A step of setting this as a new rotation speed command value (f _m4 ^* );
(C-4) The step of controlling the rotational speed so as to eliminate the difference (Δf _m ^* ) from the rotational speed command value updated in the step (c-3) is performed. Motor control method. 7. The pulsation frequency according to claim 3, wherein the pulsation frequency is twice the frequency of an alternating voltage (V _ac ) provided to apply the torque to the motor (2). Motor control method. A control device that controls the rotational speed (f _m ) of the motor (2) based on a rotational speed command value (f _m1 ^* ) that is a command value thereof,
If the rotational speed command value is within the rotational speed range (f _{beat +} , f _beat- ) where the roaring sound of the motor is generated, the rotational speed command value is changed to a boundary value (f _m10 , A motor control device comprising a rotation speed command value update unit (11; 14; 15) that changes to f _m11 , f _m12 ; f _m10 ; f _m10 ). A speed control unit (12);
The speed control unit is based on a deviation (Δf _m ^* ) between the rotation speed command value (f _m ^* ) obtained from the rotation speed command value update unit (11) and the rotation speed (f _m ). The motor control device according to claim 8, wherein the rotation speed is controlled. A first operation unit (13);
A first frequency (n · f _m ) that is a first integer (n) times the rotational speed (f _m ) and a second frequency that is a second integer (m) times the pulsation frequency (f _T ) at which the torque pulsates. A predetermined value (m · f _T / n = f _m10 ) of the rotational speed at which (m · f _T ) substantially coincides with the range as one of the boundary values;
The first calculation unit obtains the predetermined value,
The motor control device according to claim 8, wherein the rotation speed command value update unit (11; 14; 15) employs the predetermined value as the boundary value at which the rotation speed command value is changed. A speed control unit (12);
The speed control unit is based on a deviation (Δf _m ^* ) between the rotation speed command value (f _m ^* ) obtained from the rotation speed command value update unit (11) and the rotation speed (f _m ). The motor control device according to claim 10, wherein the rotation speed is controlled. A speed control unit (12);
The rotation speed command value update unit (14)
A skip operation unit (141) for outputting the predetermined value (m · f _T / n = f _m10 = f _m2 ^* ) when the rotation speed command value (f _m1 ^* ) before the change is within the range;
And a predetermined value and the rotational speed (f _m) and deviation (Delta] f _m) a new speed command value to converge to zero (f _m3 ^*) deviation converging unit for generating (142),
11. The speed control unit according to claim 10, wherein the speed control unit controls the rotation speed based on a deviation (Δf _m ^* ) between the rotation speed command value obtained from the deviation convergence unit and the rotation speed (f _m ). Motor control device. A speed control unit (12);
The rotational speed command value update unit (15)
A skip operation unit (151) for outputting the predetermined value (m · f _T / n = f _m10 = f _m2 ^* ) when the rotational speed command value (f _m1 ^* ) before the change is within the range;
A second arithmetic unit (155) for obtaining a first phase (n · θ _m ) by multiplying the phase (θ _m ) of the motor (2) by the first integer (n);
A third computing unit (152) for obtaining a second phase (m · θ _T ) by multiplying the phase (θ _T ) at which the torque pulsates by the second integer (m);
A deviation convergence unit (153) that generates a new rotational speed command value (f _m4 ^* ) in order to converge the deviation (Δθ _m ) between the first phase and the second phase to zero;
11. The speed control unit according to claim 10, wherein the speed control unit controls the rotation speed based on a deviation (Δf _m ^* ) between the rotation speed command value obtained from the deviation convergence unit and the rotation speed (f _m ). Motor control device. 14. The pulsation frequency (f _T ) according to any one of claims 10 to 13, wherein the pulsation frequency (f _T ) is twice the frequency of an AC voltage (V _ac ) provided to apply the torque to the motor (2). The motor control apparatus as described in one. Voltage converter (4)
Further comprising
AC voltage is supplied to the voltage converter,
The voltage converter is
A converter (41) for rectifying the AC voltage and outputting a DC voltage;
An inverter (42) for converting the DC voltage into a desired AC voltage;
The motor control device according to any one of claims 8 to 14, further comprising a capacitor (C) that bypasses harmonics generated by switching of the inverter.

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