Synchronous motor control device and synchronous motor control method

Abstract

To provide a control device capable of obtaining a high suppression effect relative to pulsation of a rotary shaft generated in a synchronous motor.SOLUTION: A control device 6 includes: a compensation current generation unit 38 for generating a compensation current for suppressing pulsation of a rotary shaft; and an addition unit 18 for superposing the compensation current on a current command value. The compensation current generation unit 38 includes: an induced voltage harmonic estimation unit 40 for estimating an induced voltage harmonic component eh; an induced voltage harmonic component extraction unit 42 that extracts an amplitude eqnhamp and a phase ζ qnh of one of the components from the induced voltage harmonic component eh; a current harmonic component extraction unit 44 that extracts an amplitude iqnhamp and a phase δqnh of one of the components from a current harmonic component iqh included in a current flowing through a synchronous motor 2; and a correction current generation unit 46 that generates a compensation current such that the amplitudes iqnhamp coincide with an amplitude command value Iqnhamp of the compensation current generated from the amplitude eqnhamp and the phase δqnh coincides with the phase ζqnh.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a control device for a synchronous motor and the like, and particularly to a control device for a synchronous motor that suppresses pulsation of a rotating shaft generated in the synchronous motor and the like.

Background Art

[0002] Conventionally, in order to suppress pulsation of a rotating shaft generated in a synchronous motor, a control device that suppresses pulsation of the rotating shaft by generating a compensation current and controlling the synchronous motor so as to follow a command value of the generated compensation current is known. For example, Patent Document 1 discloses a control device that generates a compensation current based on the amplitude of a flux harmonic generated in a synchronous motor acquired in advance and the phase difference between a fundamental wave current and a harmonic current flowing in the synchronous motor acquired in advance, and suppresses pulsation of the rotating shaft.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the control device described in Patent Document 1, the amplitude of the flux harmonic generated in the synchronous motor may change due to a temperature change of the synchronous motor or variations in the magnets of the synchronous motor. Further, in the control device, the phase of the flux harmonic may change due to variations in the width of the magnets of the synchronous motor or the pitch of the magnets. In such a case, the control device cannot generate a compensation current corresponding to a change in either the amplitude or the phase of the flux harmonic, so the effect of suppressing pulsation of the rotating shaft generated in the synchronous motor is reduced.

[0005] Therefore, an object of the present disclosure is to provide a control device for a synchronous motor that can achieve a high suppression effect on pulsation of the rotating shaft that occurs in the synchronous motor. [Means for solving the problem]

[0006] In order to achieve the above object, a control device for a synchronous motor according to one embodiment of the present disclosure includes: a position and speed calculation unit that calculates a rotational position and a rotational speed of a rotor of the synchronous motor using an output of an angle detector that detects a rotation angle of the synchronous motor; a current command conversion unit that converts an output of a controller that causes the synchronous motor to follow a rotational speed command value into a d-axis current command value and a q-axis current command value of a rotating coordinate system in vector control; a uvw / dq conversion unit that converts three-phase currents flowing through the synchronous motor into d-axis currents and q-axis currents of the rotating coordinate system; an inverter that controls the synchronous motor based on a difference between the d-axis current command value and the d-axis current and a difference between the q-axis current command value and the q-axis current; a compensation current generation unit that generates a q-axis compensation current that suppresses pulsation of a rotating shaft generated in the synchronous motor; and an adder that superimposes the q-axis compensation current generated by the compensation current generation unit on the q-axis current command value converted by the current command conversion unit. an induced voltage harmonic estimating unit that estimates induced voltage harmonic components induced in a winding from the rotor of the synchronous motor based on the current, the q-axis current, the d-axis voltage and q-axis voltage applied to the synchronous motor, and the rotational position and the rotational speed calculated by the position and speed calculating unit; an induced voltage harmonic component extracting unit that extracts the amplitude and phase of one component from the induced voltage harmonic components estimated by the induced voltage harmonic estimating unit; and an induced voltage harmonic component extracting unit that extracts the amplitude and phase of one component from the current harmonic components included in the q-axis current. The compensation current generating unit includes a current harmonic component extracting unit that extracts an amplitude and a phase, and a correction current generating unit that generates the q-axis compensation current so that the amplitude of the one component extracted by the current harmonic component extracting unit matches an amplitude command value of the q-axis compensation current generated based on the amplitude of the one component extracted by the induced voltage harmonic component extracting unit, and so that the phase of the one component extracted by the current harmonic component extracting unit matches a phase of the one component extracted by the induced voltage harmonic component extracting unit.

[0007] In order to achieve the above object, a control device for a synchronous motor according to an embodiment of the present disclosure includes: a position and speed estimating unit that estimates a rotational position and a rotational speed of a rotor of a synchronous motor; a current command converting unit that converts an output of a controller that causes the output of the controller to follow a rotational speed command value of the synchronous motor into a d-axis current command value and a q-axis current command value of a rotating coordinate system in vector control; a uvw / dq converting unit that converts a three-phase current flowing through the synchronous motor into a d-axis current and a q-axis current of the rotating coordinate system; an inverter that controls the synchronous motor based on a difference between the d-axis current command value and the d-axis current and a difference between the q-axis current command value and the q-axis current; a compensation current generating unit that generates a q-axis compensation current that suppresses rotating shaft pulsation of the synchronous motor; and an adder that superimposes the q-axis compensation current generated by the compensation current generating unit on the q-axis current command value converted by the current command converting unit. an induced voltage harmonic estimating unit that estimates induced voltage harmonic components induced in a winding from the rotor of the synchronous motor based on a d-axis voltage and a q-axis voltage applied to the rotor and the rotational position and the rotational speed estimated by the position and speed estimating unit; an induced voltage harmonic component extracting unit that extracts the amplitude and phase of one component from the induced voltage harmonic components estimated by the induced voltage harmonic estimating unit; and a current harmonic extracting unit that extracts the amplitude and phase of one component from current harmonic components included in the q-axis current. a current harmonic component extraction unit that outputs a current harmonic component that corresponds to a q-axis compensation current command value, and a correction current creation unit that generates the q-axis compensation current so that the amplitude of the one component extracted by the current harmonic component extraction unit matches an amplitude command value of the q-axis compensation current generated based on the amplitude of the one component extracted by the induced voltage harmonic component extraction unit, and so that the phase of the one component extracted by the current harmonic component extraction unit matches a phase of the one component extracted by the induced voltage harmonic component extraction unit.

[0008] In order to achieve the above object, a control method for a synchronous motor according to an embodiment of the present disclosure includes: a position and speed calculation step of calculating a rotational position and a rotational speed of a rotor of the synchronous motor using an output of an angle detector that detects a rotation angle of the synchronous motor; a current command conversion step of converting an output of a controller that causes the synchronous motor to follow a rotation command value into a d-axis current command value and a q-axis current command value of a rotating coordinate system in vector control; a uvw / dq conversion step of converting three-phase currents flowing through the synchronous motor into d-axis currents and q-axis currents of the rotating coordinate system; a control step of controlling the synchronous motor based on a difference between the d-axis current command value and the d-axis current and a difference between the q-axis current command value and the q-axis current; a compensation current generation step of generating a q-axis compensation current that suppresses pulsation of a rotating shaft generated in the synchronous motor; and an addition step of superimposing the q-axis compensation current generated in the compensation current generation step on the q-axis current command value converted in the current command conversion step. an induced voltage harmonic estimation step of estimating induced voltage harmonic components induced in a winding from the rotor of the synchronous motor based on the current, the q-axis current, the d-axis voltage and q-axis voltage applied to the synchronous motor, and the rotational position and the rotational speed calculated in the position and speed calculation step; an induced voltage harmonic component extraction step of extracting the amplitude and phase of one component from the induced voltage harmonic components estimated in the induced voltage harmonic estimation step; and an induced voltage harmonic component extraction step of extracting the amplitude and phase of one component from current harmonic components included in the q-axis current. and a correction current generation step of generating the q-axis compensation current so that the amplitude of the one component extracted in the current harmonic component extraction step matches an amplitude command value of the q-axis compensation current generated based on the amplitude of the one component extracted in the induced voltage harmonic component extraction step, and so that the phase of the one component extracted in the current harmonic component extraction step matches the phase of the one component extracted in the induced voltage harmonic component extraction step.

[0009] In order to achieve the above object, a control method for a synchronous motor according to an embodiment of the present disclosure includes: a position and speed estimation step of estimating a rotational position and a rotational speed of a rotor of the synchronous motor; a current command conversion step of converting an output of a controller that follows a rotation command value of the synchronous motor into a d-axis current command value and a q-axis current command value of a rotating coordinate system in vector control; a uvw / dq conversion step of converting three-phase currents flowing through the synchronous motor into d-axis currents and q-axis currents of the rotating coordinate system; a control step of controlling the synchronous motor based on a difference between the d-axis current command value and the d-axis current and a difference between the q-axis current command value and the q-axis current; a compensation current generation step of generating a q-axis compensation current that suppresses rotating shaft pulsation of the synchronous motor; and an addition step of superimposing the q-axis compensation current generated in the compensation current generation step on the q-axis current command value converted in the current command conversion step. an induced voltage harmonic estimation step of estimating induced voltage harmonic components induced in a winding from the rotor of the synchronous motor based on the d-axis voltage and q-axis voltage estimated in the position and speed estimation step and the rotational position and the rotational speed estimated in the position and speed estimation step; an induced voltage harmonic component extraction step of extracting the amplitude and phase of one component from the induced voltage harmonic components estimated in the induced voltage harmonic estimation step; and a current harmonic extraction step of extracting the amplitude and phase of one component from current harmonic components included in the q-axis current. The method includes a harmonic component extraction step, and a correction current creation step of generating the q-axis compensation current so that the amplitude of the one component extracted in the current harmonic component extraction step matches an amplitude command value of the q-axis compensation current generated based on the amplitude of the one component extracted in the induced voltage harmonic component extraction step, and so that the phase of the one component extracted in the current harmonic component extraction step matches the phase of the one component extracted in the induced voltage harmonic component extraction step.

[0010] To achieve the above goal, a program, control algorithm, etc. according to one embodiment of the present disclosure causes a digital processor or electronic integrated circuit to execute the above-described synchronous motor control method. [Effects of the Invention]

[0011] The present disclosure provides a control device for a synchronous motor that can achieve a high suppression effect on pulsation of the rotating shaft that occurs in the synchronous motor. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a block diagram showing the configuration of a system including a control device according to the first embodiment. [Figure 2] FIG. 2 is a block diagram showing a first configuration example of the compensation current generating unit shown in FIG. [Figure 3] FIG. 3 is a block diagram showing a second configuration example of the compensation current generating unit shown in FIG. [Figure 4] FIG. 4 is a block diagram showing a third example of the configuration of the compensation current generating unit shown in FIG. [Figure 5] FIG. 5 is a flowchart showing the operation performed by the control device according to the first embodiment. [Figure 6] FIG. 6 is a block diagram showing a modification of the control device according to the first embodiment. [Figure 7] FIG. 7 is a block diagram showing a configuration of a system including a control device according to the second embodiment. [Figure 8] FIG. 8 is a flowchart showing the operation performed by the control device according to the second embodiment. [Figure 9] FIG. 9 is a block diagram showing a modified example of the control device according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. Note that each of the embodiments described below represents a specific example of the present disclosure. The numerical values, components, component placement and connection configurations, steps, step order, display examples, etc. shown in the following embodiments are merely examples and are not intended to limit the present disclosure. Therefore, among the components in the following embodiments, components that are not recited in the independent claims of the present disclosure will be described as optional components. Furthermore, each figure is not necessarily an exact illustration. In each figure, substantially identical components are assigned the same reference numerals, and redundant explanations are omitted or simplified.

[0014] (Embodiment 1) [Control device configuration] 1 is a block diagram showing the configuration of a system including a control device 6 according to the first embodiment. The present disclosure is made up of a synchronous motor 2, an angle detector 4, and the control device 6.

[0015] The synchronous motor 2 is a motor, such as a three-phase permanent magnet motor with a permanent magnet as the rotor and motor windings as the stator. The synchronous motor 2 is, for example, a surface permanent magnet motor. The control device 6 controls surface permanent magnet motors and the like.

[0016] The angle detector 4 detects the rotation angle θ of the rotor of the synchronous motor 2. m These are position sensors such as encoders and resolvers that detect the position of the object.

[0017] The control device 6 performs speed control to match the rotational speed command value instructed to the synchronous motor 2 with the rotational speed (number of rotations) of the rotor of the synchronous motor 2 based on the information on the rotational angle output by the angle detector 4. Alternatively, position control may be added to generate the rotational speed command value by making the rotational position of the synchronous motor 2 follow a target rotational position. Furthermore, torque control may be performed to control the current to the synchronous motor 2 to generate a target torque.

[0018] The control device 6 includes a differentiator 8, a controller 10, a current command conversion unit 12, a differentiator 14, a controller 16, an adder 18, a differentiator 20, a controller 22, a dq / uvw conversion unit 24, an inverter 26, a first current sensor 28, a second current sensor 30, a third current sensor 32, a uvw / dq conversion unit 34, a position / speed calculation unit 36, and a compensation current generation unit 38. Some or all of the components of the control device 6 may be implemented by a control application executed on a DSP (Digital Signal Processor) or a microcomputer. The DSP or microcomputer may include peripheral devices such as a core, a memory, an A / D conversion circuit, and a communication port. Some or all of the components of the control device 6 may be implemented by a logic circuit.

[0019] The difference calculator 8 calculates the rotation speed command value (for example, the command rotation speed ω ref The difference between the rotation speed ω of the rotor of the synchronous motor 2 output by the position and speed calculation unit 36 ​​is calculated.

[0020] Based on the difference calculated by the differentiator 8, the controller 10 generates a command value for making the rotation speed of the synchronous motor 2 follow the rotation speed command value.

[0021] The current command conversion unit 12 converts the command value output by the controller 10 into a d-axis current command value I d * and the q-axis current command value I q * The dq coordinate system is a coordinate system in which the phase of the rotor of the synchronous motor 2 is the d-axis and the phase that is 90 degrees ahead of the d-axis is the q-axis. In other words, the d-axis current command value I d * is the command value of the d-axis component among the command values ​​output by the controller 10, and the q-axis current command value I q * is the command value of the q-axis component among the command values ​​output by the controller 10.

[0022] The difference calculator 14 calculates the d-axis current command value Id * and the d-axis current I output by the uvw / dq conversion unit 34. d The difference between the d-axis current I d is the three-phase current I u , I v , I w The three-phase current is the d-axis component current value converted from the

[0023] The controller 16 calculates the d-axis voltage V d The d-axis voltage V d is the voltage value of the d-axis component of the voltage applied to the synchronous motor 2.

[0024] The adder 18 converts the q-axis current command value I q * and the n-th compensation current I output by the compensation current generating unit 38. qnh Here, n is an integer equal to or greater than 2. In addition, the n-th compensation current I qnh is a current value generated to cancel out the n-th order component contained in the pulsation of the synchronous motor 2.

[0025] The difference calculator 20 calculates the current value output by the adder 18 (i.e., the q-axis current command value I q * and n-th compensation current I qnh and the q-axis current I q The difference between the q-axis current I q is the three-phase current I u , I v , I w is the current value of the q-axis component converted from

[0026] The controller 22 calculates the q-axis voltage V q The q-axis voltage Vq is the voltage value of the q-axis component of the voltage applied to the synchronous motor 2.

[0027] The dq / uvw conversion unit 24 converts the d-axis voltage V d and the q-axis voltage V output by the controller 22. q and the U phase voltage V u and V phase voltage V v and W-phase voltage V w Specifically, the dq / uvw conversion unit 24 converts the rotational position θ of the rotor of the synchronous motor 2 calculated by the position and speed calculation unit 36 ​​into e Based on this, the d-axis voltage V d and the q-axis voltage V q and the U phase voltage V u and V phase voltage V v and W-phase voltage V w Convert to and.

[0028] The inverter 26 is, for example, a PWM (Pulse Width Modulation) inverter. d * and d-axis current I d and the q-axis current command value I q * and q-axis current I q Specifically, the inverter 26 controls the synchronous motor 2 based on the difference between the U-phase voltage V output from the dq / uvw conversion unit 24. u and V phase voltage V v and W-phase voltage V w Based on this, the U-phase current I u and V-phase current I v and W-phase current I w and supplied to the synchronous motor 2.

[0029] The first current sensor 28 detects the U-phase current I output from the inverter 26. u and outputs it to the uvw / dq conversion unit 34.

[0030] The second current sensor 30 detects the V-phase current I output from the inverter 26. v and outputs it to the uvw / dq conversion unit 34.

[0031] The third current sensor 32 detects the W-phase current I output by the inverter 26. w and outputs it to the uvw / dq conversion unit 34.

[0032] The uvw / dq conversion unit 34 converts the three-phase current (i.e., the U-phase current I u and V-phase current I v and W-phase current I w and ) is the d-axis current I d and q-axis current I q Specifically, the uvw / dq conversion unit 34 converts the rotational position θ of the rotor of the synchronous motor 2 calculated by the position and speed calculation unit 36 ​​into e Based on this, the three-phase current is converted into the d-axis current I d and q-axis current I q Convert to.

[0033] The position and speed calculation unit 36 ​​calculates the rotation angle θ of the rotor output by the angle detector 4. m Based on this, the rotational position θ of the rotor of the synchronous motor 2 is calculated. e and the rotation speed ω are calculated.

[0034] The compensation current generating unit 38 generates a compensation current that suppresses pulsation (i.e., torque ripple) of the rotating shaft generated in the synchronous motor 2. Specifically, the compensation current generating unit 38 generates a compensation current that suppresses pulsation (i.e., torque ripple) of the rotating shaft generated in the synchronous motor 2. d and the q-axis voltage V output by the controller 22. q and the d-axis current I output by the uvw / dq conversion unit 34. d and q-axis current I q and the rotational position θ output by the position and velocity calculation unit 36. e and the rotation speed ω, the nth-order compensation current I qnh The compensation current generating unit 38 generates the rotational position θ e Without obtaining the rotational speed ω, the rotational position θ e may be calculated.

[0035] [Principles of torque ripple suppression] The principle of torque ripple suppression performed by the compensation current generating unit 38 will be described below.

[0036] The armature interlinkage magnetic flux Φ due to the permanent magnet of the synchronous motor 2 is expressed as in equation (1). Note that Φ1 is the magnetic flux generated by the fundamental wave component. Φ n-1 is the magnetic flux generated by the n-1th harmonic component, and Φ n+1 , Φ m-1 , and Φ m+1 The same is true for δ n-1 is the phase shift of the n-1th harmonic component, and δ n+1 , δ m-1 , and δ m+1 The same applies to the above. Furthermore, m is an integer of 2 or more and is different from n.

[0037]

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[0038] For example, when n is 6 and m is 12, Equation (1) is a mathematical expression that indicates the 5th, 7th, 11th, and 13th harmonic components that are generally included in the armature flux linkage Φ. Furthermore, although Equation (1) shows an example in which the armature flux linkage Φ includes four harmonic components, the armature flux linkage Φ generally includes two or more harmonic components.

[0039] The induced voltage em that occurs in the motor windings (the stator) when the permanent magnet (the rotor) rotates is expressed as in equation (2). Note that equation (2) is calculated by differentiating equation (1) with respect to time.

[0040]

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[0041] The induced voltage em obtained from equation (2) is converted into the d-axis induced voltage e d and q-axis induced voltage e q By converting into , we obtain equation (3). In equation (3), ωe is the electrical rotation speed. f is the magnetic flux of the fundamental wave component. fs(n-1) and Ψ fc(n-1) are expressed by equations (4) and (5), respectively, and Ψ fs(n+1) , Ψ fc(n+1) , Ψ fs(m-1) , Ψ fc(m-1) , Ψ fs(m+1) , and Ψ fc(m+1) The same is true for Φ dnh is the magnetic flux Φ generated by the nth harmonic component n indicates the d-axis component of the magnetic flux, and Φ qnh is the magnetic flux Φ generated by the nth harmonic component n The magnetic flux of the q-axis component is shown. dmh and Φ qmh The same is true for ζ dnh is the phase shift of the d-axis component caused by the n-th harmonic component. dmh , ζ qnh and ζ qmh The same is true for

[0042]

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[0043]

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[0044]

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[0045] In equation (3), the first term on the right side represents the induced voltage due to the fundamental wave, the second term on the right side represents the induced voltage due to the nth harmonic component, and the third term on the right side represents the induced voltage due to the mth harmonic component.

[0046] The torque generated in the synchronous motor 2 is expressed by equation (6). Specifically, equation (6) is expressed by the d-axis induced voltage e d and q-axis induced voltage e qand the current flowing through the synchronous motor 2. In equation (6), the U-phase current I u and V-phase current I v and W-phase current I w and the converted d-axis current I d and q-axis current I q is used. Also, N p is the number of pairs of magnet poles of the synchronous motor 2. Also, ω is the mechanical rotation speed, and ω is the electrical rotation speed. e is the number of pairs of magnet poles of synchronous motor 2, N p It is obtained by dividing by

[0047]

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[0048] In equation (6), the first term on the right-hand side represents the torque generated by the fundamental wave, the second term on the right-hand side represents the pulsation of the rotating shaft generated by the nth-order harmonic component (i.e., the nth-order torque ripple), and the third term on the right-hand side represents the pulsation of the rotating shaft generated by the mth-order harmonic component (i.e., the mth-order torque ripple).

[0049] Furthermore, when the synchronous motor 2 is a surface permanent magnet motor, in equation (6), I d =0, and equation (6) can be rewritten as equation (7).

[0050]

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[0051] In equation (7), similar to equation (6), the first term on the right side represents the torque generated by the fundamental wave, the second term on the right side represents the nth-order torque ripple, and the third term on the right side represents the mth-order torque ripple.

[0052] The compensation current generating unit 38 intentionally generates the q-axis current I q compensation current (i.e., nth-order compensation current I qnh and m-th compensation current I qmhThe compensation current generating unit 38 thus superimposes the n-th order torque ripple and the m-th order torque ripple to cancel each other out.

[0053]

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[0054] [Example of compensation current generation section] Next, a detailed configuration example of the compensation current generating unit 38 shown in FIG. 1 will be described with reference to FIGS. 2 to 4. In addition to the detailed configuration example of the compensation current generating unit 38, an operation for generating a compensation current will also be described. In any of the configurations shown in FIGS. 2 to 4, the compensation current generating unit 38 generates an n-th compensation current I qnh and generates the nth-order compensation current I qnh is output to the adder 18.

[0055] FIG. 2 is a block diagram showing a first example of the configuration of the compensation current generating unit 38 shown in FIG.

[0056] As shown in FIG. 2, the compensation current generation unit 38 includes an induced voltage harmonic estimation unit 40, an induced voltage harmonic component extraction unit 42, a current harmonic component extraction unit 44, a correction current creation unit 46, an amplitude calculation unit 50, a compensation current amplitude calculation unit 52, and a phase calculation unit 54.

[0057] The induced voltage harmonic estimation unit 40 estimates the d-axis voltage V d and the q-axis voltage V output by the controller 22. q and the d-axis current I output by the uvw / dq conversion unit 34. d and q-axis current I q and the rotational position θ output by the position and velocity calculation unit 36. e and the rotation speed ω, the induced voltage harmonic component e induced in the winding from the rotor of the synchronous motor 2 h The induced voltage harmonic estimator 40 estimates the rotational position θ e Without obtaining the rotational speed ω, the rotational position θ eCalculate the induced voltage harmonic component e h may be estimated.

[0058] Specifically, the induced voltage harmonic estimating unit 40 calculates the induced voltage harmonic component e using the electrical equation shown in Equation (9). h In equation (9), L d is the inductance of the d-axis component of the inductance L of the synchronous motor 2, and L q is the inductance of the q-axis component of the inductance L of the synchronous motor 2. R is the winding resistance of the synchronous motor 2. v d is the d-axis voltage applied to the synchronous motor 2, and v q is the q-axis voltage applied to the synchronous motor 2. d is the d-axis current output by the uvw / dq conversion unit 34, and i q is the q-axis current output by the uvw / dq conversion unit 34.

[0059]

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[0060] In addition, the induced voltage harmonic component e h is expressed as in equation (10).

[0061]

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[0062] In equation (10), the first term on the right side is the nth-order induced voltage harmonic component e nh The second term on the right side is the m-th order induced voltage harmonic component e mh Shows.

[0063] In addition, the induced voltage harmonic component e h By transforming equations (9) and (10), it is expressed as equation (11). In equation (11), e dh is the induced voltage harmonic component e h indicates the d-axis component of the magnetic flux, and eqh is the induced voltage harmonic component e h The magnetic flux of the q-axis component is shown. dnh , e qnh , e dmh , and e qmh The same is true for

[0064]

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[0065] The induced voltage harmonic component extractor 42 extracts the induced voltage harmonic component e estimated by the induced voltage harmonic estimator 40. h For example, the induced voltage harmonic component extractor 42 extracts the amplitude and phase of one component from the induced voltage harmonic component e estimated by the induced voltage harmonic estimator 40. h , the induced voltage harmonic component e h The amplitude and phase of one component are extracted by multiplying the sin and cos operators using the rotation angle of the compensation current generator 38. qnh This refers to the nth harmonic component used to generate

[0066] The induced voltage harmonic component extractor 42 includes an n-th order component extractor 48 .

[0067] The n-th order component extractor 48 extracts the induced voltage harmonic component e estimated by the induced voltage harmonic estimator 40. h The q-axis component of the n-th order induced voltage harmonic component is the induced voltage harmonic component e qn Specifically, the n-th order component extractor 48 extracts the induced voltage harmonic component e qn Extract '.

[0068]

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[0069] The n-th order component extraction unit 48 extracts the induced voltage harmonic component e obtained by equation (12). qn' is filtered using a low-pass filter to obtain the induced voltage harmonic component e qnhLPF The induced voltage harmonic component e extracted by the n-th order component extractor 48 is qnhLPF corresponds to one component extracted by the induced voltage harmonic component extractor 42.

[0070]

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[0071] The amplitude calculation unit 50 calculates the induced voltage harmonic component e extracted by the n-th order component extraction unit 48. qnhLPF Based on the amplitude of the magnetic flux Φ qnh Specifically, the amplitude calculation unit 50 calculates the amplitude Φ of the magnetic flux using equation (14). qnh The amplitude Φ of the magnetic flux calculated by the amplitude calculation unit 50 is calculated as follows. qnh corresponds to the amplitude of one component extracted by the induced voltage harmonic component extractor 42.

[0072]

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[0073] The compensation current amplitude calculation unit 52 calculates the amplitude Φ of the magnetic flux calculated by the amplitude calculation unit 50. qnh Specifically, the compensation current amplitude calculation unit 52 derives equation (16) using equation (15) to calculate the amplitude I of the n-th order compensation current. qnhCmd Calculate the amplitude of the calculated nth-order compensation current I qnhCmd The amplitude command value I of the compensation current qnhamp Generate it as:

[0074]

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[0075]

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[0076] The phase calculation unit 54 calculates the induced voltage harmonic component e extracted by the n-th order component extraction unit 48. qnhLPF Based on this, the phase command value ζ of the nth-order compensation current qnh Specifically, the phase calculation unit 54 calculates the phase command value ζ of the n-th order compensation current using equation (17). qnh The phase command value ζ of the n-th order compensation current calculated by the phase calculation unit 54 is qnh corresponds to the phase of one component extracted by the induced voltage harmonic component extractor 42.

[0077]

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[0078] The current harmonic component extractor 44 extracts the q-axis current I q Current harmonic components i qh The amplitude and phase of one component are extracted from the current harmonic component i qh is the q-axis current I of the three-phase current supplied to the synchronous motor 2. q In addition, one component means a harmonic component included in the n-th compensation current I qnh This refers to the nth harmonic component used to generate

[0079] The current harmonic component extractor 44 includes a low-pass filter 56 , an n-th order component extractor 58 , an amplitude calculator 60 , and a phase calculator 62 .

[0080] The low-pass filter 56 filters the q-axis current I q The fundamental component is removed from the current harmonic component i qh Extract.

[0081] The n-th order component extractor 58 extracts the current harmonic component i qh to n-th order current harmonic component i qnh Specifically, the n-th order component extractor 58 extracts the n-th order current harmonic component i qnh In equation (18), i qmhis the current harmonic component i extracted by the low-pass filter 56. qh Among these, it is the m-th order current harmonic component.

[0082]

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[0083] The n-th order component extractor 58 extracts the n-th order current harmonic component i obtained by equation (18). qnh is filtered using a low-pass filter to obtain the n-th harmonic current component i qnhLPF The n-th order current harmonic component i extracted by the n-th order component extractor 48 is qnhLPF corresponds to one component extracted by the current harmonic component extractor 44.

[0084]

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[0085] The amplitude calculation unit 60 calculates the n-th order current harmonic component i extracted by the n-th order component extraction unit 58. qnhLPF Based on this, the amplitude of the nth-order current harmonic component i qnhamp Specifically, the amplitude calculation unit 60 calculates the amplitude i of the n-th order current harmonic component using equation (20). qnhamp The amplitude i of the n-th order current harmonic component calculated by the amplitude calculation unit 60 is calculated. qnhamp corresponds to the amplitude of one component extracted by the current harmonic component extractor 44.

[0086]

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[0087] The phase calculation unit 62 calculates the n-th order current harmonic component i extracted by the n-th order component extraction unit 58. qnhLPF Based on this, the phase δ of the nth-order current harmonic component qnh Specifically, the phase calculation unit 62 calculates the phase δ of the n-th order current harmonic component using equation (21). qnhThe phase δ of the n-th order current harmonic component calculated by the phase calculation unit 62 is qnh corresponds to the phase of one component extracted by the current harmonic component extractor 44.

[0088]

number

[0089] The compensation current generating unit 46 generates the compensation current amplitude command value I based on the amplitude of one component extracted by the induced voltage harmonic component extracting unit 42. qnhamp The amplitude i of one component extracted by the current harmonic component extractor 44 is qnhamp and the phase command value ζ of one component generated and extracted by the induced voltage harmonic component extractor 42 qnh The phase δ of one component extracted by the current harmonic component extractor 44 is qnh The compensation current (i.e., the nth-order compensation current I qnh )

[0090] The correction current generating unit 46 includes a differentiator 64 , a PI controller 66 , a differentiator 68 , a PI controller 70 , and a calculation unit 72 .

[0091] The difference calculator 64 calculates the compensation current amplitude command value I qnhamp and the amplitude i of one component output by the amplitude calculation unit 60 qnhamp The difference between these is calculated and output to the PI controller 66.

[0092] The PI controller 66 adjusts the amplitude I of the compensation current so that the difference output by the difference calculator 64 approaches zero. qnhamp and outputs the output value to the calculation unit 72.

[0093] The differentiator 68 calculates the phase command value ζ of one component output by the phase calculation unit 54. qnh and the phase δ of one component output by the phase calculation unit 62 qnh The difference between these is calculated and output to the PI controller 70.

[0094] The PI controller 70 adjusts the phase δ of one component so that the difference output by the differentiator 68 approaches zero. qnh and outputs the output to the calculation unit 72.

[0095] 3, the calculation unit 78 performs the calculation shown in equation (22), and the calculation result obtained by equation (22) is passed through a low-pass filter to extract the second term on the right side of equation (22). The PI controller 70 adjusts the phase δ of one component so that the value of the extracted second term on the right side becomes 0.5. qnh Adjust.

[0096]

number

[0097] The calculation unit 72 calculates the amplitude I of the compensation current output by the PI controller 66. qnhamp and the phase ζ output by the PI controller 70 qnh and based on the nth-order compensation current I qnh Specifically, the calculation unit 72 uses the equation (23) to generate the n-th order compensation current I qnh Generate.

[0098]

number

[0099] From the above explanation, the control device 6 can calculate the induced voltage harmonic component e h and current harmonic components i qh Since the amplitude and phase are generated for each component extracted from, it is possible to generate a compensation current corresponding to a change in either the amplitude or phase of the magnetic flux harmonic.

[0100] The control device 6 also detects the induced voltage harmonic component e h Rotational position θ e Considering the amplitude of one component extracted from the induced voltage harmonic components, e qnhamp and phase ζ qnhSince the above-mentioned values ​​are extracted, it is possible to generate a compensation current that corresponds to more detailed changes.

[0101] Fig. 3 is a block diagram showing a second configuration example of the compensation current generating unit 38 shown in Fig. 1. Note that, of the compensation current generating unit 38 shown in Fig. 3, components that are similar to those of the compensation current generating unit 38 shown in Fig. 2 have already been explained, so they are assigned the same reference numerals and their explanations are omitted, and the explanation will focus on the differences from the compensation current generating unit 38 shown in Fig. 2.

[0102] The compensation current generating unit 38 shown in FIG. 3 differs from the compensation current generating unit 38 shown in FIG. 2 in that the current harmonic component extracting unit 44 is replaced by a current harmonic component extracting unit 44a, the correction current creating unit 46 is replaced by a correction current creating unit 46a, and in that it has a phase synthesis unit 74.

[0103] The phase synthesis unit 74 calculates the phase command value ζ of the n-th order compensation current calculated by the phase calculation unit 54. qnh and a rotational position θ calculated from the rotational speed ω of the rotor of the synchronous motor 2. e Based on this, the sine wave of the nth compensation current sin(nθ e +ζ qnh ) is input to the compensation current generating unit 38 instead of the rotor rotation speed ω. e Using this, the sine wave of the nth compensation current sin(nθ e +ζ qnh ) may be synthesized.

[0104] 2 in that the current harmonic component extractor 44a includes a phase combiner 76. The current harmonic component extractor 44a differs from the current harmonic component extractor 44 shown in FIG.

[0105] The phase synthesis unit 76 synthesizes the phase δ of the n-th order current harmonic component calculated by the phase calculation unit 62. qnh and a rotational position θ calculated from the rotational speed ω of the rotor of the synchronous motor 2. e Based on this, the sine wave sin(nθ) of the nth-order current harmonic component e +δ qnh) is input to the compensation current generating unit 38 instead of the rotor rotation speed ω. e Using the nth harmonic current sine wave sin(nθ e +δ qnh ) may be synthesized.

[0106] In addition, the correction current generating unit 46a differs from the correction current generating unit 46 shown in FIG. 2 in that it has an arithmetic unit 78 and a low-pass filter 80, and in that the difference calculator 68 has been replaced with a difference calculator 68a.

[0107] The calculation unit 78 calculates the sine wave sin(nθ) of the n-th order compensation current output by the phase synthesis unit 74. e +ζ qnh ) and the sine wave sin(nθ e +δ qnh ) and perform the calculation shown in the above equation (22).

[0108] The low-pass filter 80 extracts the second term from the calculation result output by the calculation unit 78 (the right-hand side of the above-mentioned equation (22)).

[0109] The differentiator 68a calculates the difference between a predetermined command value (for example, 0.5) and the value of the second term output by the low-pass filter 80.

[0110] The PI controller 70 controls the difference output by the differentiator 68a so that it approaches zero.

[0111] From the above explanation, the control device 6 can calculate the induced voltage harmonic component e h The phase of one component extracted from qnh and current harmonic component i qh The phase δ of one component extracted from qnh Since the above is combined, a compensation current corresponding to the change in phase of the magnetic flux harmonics can be generated.

[0112] Fig. 4 is a block diagram showing a third configuration example of the compensation current generating unit 38 shown in Fig. 1. Note that, of the compensation current generating unit 38 shown in Fig. 4, components that are similar to those of the compensation current generating unit 38 shown in Fig. 3 have already been explained, so they are assigned the same reference numerals and their explanations are omitted, and the explanation will focus on the differences from the compensation current generating unit 38 shown in Fig. 3.

[0113] The compensation current generating unit 38 shown in FIG. 4 differs from the compensation current generating unit 38 shown in FIG. 3 in that the induced voltage harmonic component extracting unit 42 is replaced by an induced voltage harmonic component extracting unit 42b, the current harmonic component extracting unit 44a is replaced by a current harmonic component extracting unit 44b, the amplitude calculating unit 50 is replaced by an amplitude searching unit 84, and the phase combining unit 74 is replaced by a signal generating unit 84.

[0114] The induced voltage harmonic component extractor 42b differs from the induced voltage harmonic component extractor 42 shown in FIG. 3 in that the nth-order component extractor 48 is replaced with an nth-order component extractor 48b.

[0115] The n-th order component extractor 48b extracts the induced voltage harmonic component e estimated by the induced voltage harmonic estimator 40. h The q-axis component of the n-th order induced voltage harmonic component is the induced voltage harmonic component e qn Specifically, the n-th order component extractor 48b extracts the induced voltage harmonic component e' using a band-pass filter matched to the rotation speed ω of the synchronous motor 2. qn Extract '.

[0116] The amplitude search unit 82 searches for at least one period of the induced voltage harmonic component e extracted by the n-th order component extraction unit 48b. qn Based on ', the induced voltage harmonic components e qn Search for the maximum and minimum values ​​of the amplitude of ' and find the amplitude e of the induced voltage harmonic component. qnhamp The amplitude e of the induced voltage harmonic component identified by the amplitude search unit 82 is qnhamp corresponds to the amplitude of one component extracted by the induced voltage harmonic component extractor 42b.

[0117] The compensation current amplitude calculation unit 52 calculates the amplitude e of the induced voltage harmonic component identified by the amplitude search unit 82. qnhamp Specifically, the compensation current amplitude calculation unit 52 calculates the amplitude I of the n-th order compensation current using the above-mentioned equation (16). qnhCmd Calculate the amplitude of the calculated nth-order compensation current I qnhCmd The amplitude command value I of the compensation current qnhamp Generate it as:

[0118] The signal generating unit 84 generates the induced voltage harmonic component e extracted by the n-th order component extracting unit 48b. qn The amplitude search unit 82 finds the amplitude e qnhamp By dividing by the signal sin(nθ e +ζ qnh )

[0119] 3 in that the nth-order component extraction unit 58 is replaced by an nth-order component extraction unit 58b, the amplitude calculation unit 60 is replaced by an amplitude search unit 86, and the phase synthesis unit 76 is replaced by a signal generation unit 88, and in that the current harmonic component extraction unit 44b does not have a phase calculation unit 62.

[0120] The n-th order component extractor 58b extracts the current harmonic component i extracted by the low-pass filter 56. qh to n-th order current harmonic component i qnh Specifically, the n-th order component extractor 58b extracts the current harmonic component i using a band-pass filter that matches the rotation speed ω of the synchronous motor 2. qnh Extract.

[0121] The amplitude search unit 86 detects at least one period of the current harmonic component i extracted by the n-th order component extraction unit 58b. qnh Based on this, the nth-order current harmonic component i qnh The maximum and minimum values ​​of the amplitude of the nth-order current harmonic component are searched for. qnhamp Identify.

[0122] The signal generating unit 88 generates the current harmonic component i extracted by the n-th order component extracting unit 58b. qnhIn each case, the amplitude i found by the amplitude search unit 86 qnhamp By dividing by the signal sin(nθ e +δ qnh )

[0123] As explained above, the control device 6 does not calculate specific values ​​of the phase as in the above equations (17) and (21), and therefore can reduce the influence of calculation errors.

[0124] [Control device operation] Next, the operation performed by the control device 6 according to the first embodiment to suppress pulsation of the rotating shaft occurring in the synchronous motor 2 will be described with reference to Fig. 5. Fig. 5 is a flowchart showing the operation performed by the control device 6 according to the first embodiment.

[0125] First, the current command conversion unit 12 converts the output of the controller 10, which is made to follow the rotation speed command value, into a d-axis current command value I d * and q-axis current command value I q * (Step S101).

[0126] The adder 18 calculates the compensation current generated by the compensation current generator 38 as the q-axis current command value I q * (step S102).

[0127] The inverter 26 outputs a d-axis current command value I d * and d-axis current I d and the q-axis current command value I q * and q-axis current I q Based on the difference between the calculated values, the synchronous motor 2 is controlled (step S103).

[0128] The control device 6 determines whether or not to end the control for generating the target torque by controlling the current to the synchronous motor 2 (step S104). For example, when the synchronous motor 2 stops, the control device 6 determines to end the control.

[0129] When it is determined that the control should be ended (Yes in step S104), the control device 6 ends the control.

[0130] When it is determined that the control should not be ended (No in step S104), the position and speed calculation unit 36 ​​calculates the rotational position θ of the rotor of the synchronous motor 2. e and the rotation speed ω is calculated (step S105).

[0131] The uvw / dq conversion unit 34 converts the three-phase current flowing through the synchronous motor 2 into a d-axis current I d and q-axis current I q (step S106).

[0132] The induced voltage harmonic estimation unit 40 estimates the d-axis current I d and q-axis current I q and the d-axis voltage V applied to synchronous motor 2 d and the q-axis voltage V q and the rotational position θ calculated by the position and speed calculation unit 36 e Based on the rotation speed ω and ω, the induced voltage harmonic component e h In step S107, the compensation current generating unit 38 receives the rotational position θ e Without obtaining the rotational speed ω, the rotational position θ e may be calculated.

[0133] The induced voltage harmonic component extractor 42 extracts the induced voltage harmonic component e estimated by the induced voltage harmonic estimator 40. h to the amplitude of one component e qnhamp and phase ζ qnh (Step S108). Step S108 may be performed by induced voltage harmonic component extractor 42a shown in FIG. 3, or by induced voltage harmonic component extractor 42b shown in FIG. 4.

[0134] The current harmonic component extractor 44 extracts the q-axis current I q Current harmonic components i included in qh The amplitude of one component from i qnhamp and phase δqnh and (step S109). Note that step S109 may be performed by the current harmonic component extractor 44a shown in Fig. 3, or by the current harmonic component extractor 44b shown in Fig. 4. Step S109 may also be performed before step S107 or step S108.

[0135] The correction current generator 46 calculates the amplitude e of one of the components extracted by the induced voltage harmonic component extractor 42. qnhamp The amplitude command value I of the compensation current generated based on qnhamp The amplitude i of one component extracted by the current harmonic component extractor 44 is qnhamp and the phase ζ of one component extracted by the induced voltage harmonic component extractor 42 qnh The phase δ of one component extracted by the current harmonic component extractor 44 is qnh The compensation current is generated so as to match the values ​​of the reference voltage and the reference current (step S110). Note that step S110 may be performed by the correction current generating unit 46a shown in FIG.

[0136] [Modification of the control device] Fig. 6 is a block diagram showing a modification of the control device 6 according to embodiment 1. The control device 6 shown in Fig. 6 differs from the control device 6 shown in Fig. 1 in that it includes two adders 18a, 18b and two compensation current generators 38a, 38b.

[0137] 6, the control device 6 includes two adders 18a and 18b and two compensation current generators 38a and 38b. Specifically, the compensation current generator 38a generates an n-th order compensation current I qnh The adder 18a generates the n-th order compensation current I generated by the compensation current generator 38a. qnh is the q-axis current command value I q * In addition, the compensation current generating unit 38b generates an m-th compensation current I qmh The adder 18b generates the m-th compensation current I generated by the compensation current generator 38b. qmh is the q-axis current command value I q* is superimposed on.

[0138] In the explanation of FIG. 6, a modified example has been described in which the control device 6 has two adders 18a, 18b and two compensation current generators 38a, 38b, but the control device 6 may have three or more adders and three or more compensation current generators.

[0139] As explained above, the control device 6 generates a plurality of compensation currents for each component of the pulsation of the rotating shaft occurring in the synchronous motor 2, and therefore can obtain a higher suppression effect on the pulsation of the rotating shaft occurring in the synchronous motor 2.

[0140] [effect] As described above, the control device 6 according to this embodiment can calculate the rotation angle θ of the synchronous motor 2. m The output of the angle detector 4 that detects the rotational position θ of the rotor of the synchronous motor 2 is used to calculate the rotational position θ of the rotor of the synchronous motor 2. e and a position / speed calculation unit 36 ​​that calculates the rotation speed ω, and a controller 10 that makes the output of the controller 10 follow the rotation speed command value of the synchronous motor 2 as a d-axis current command value I in the rotating coordinate system in vector control. d * and q-axis current command value I q * and a current command conversion unit 12 converting the three-phase current flowing through the synchronous motor 2 into a d-axis current I d and q-axis current I q and a uvw / dq conversion unit 34 converting the d-axis current command value I d * and d-axis current I d and the q-axis current command value I q * and q-axis current I q a compensation current generating unit 38 that generates a q-axis compensation current that suppresses pulsation of the rotating shaft occurring in the synchronous motor 2; and a q-axis current command value I q * and an adder 18 that adds a d-axis current I d and q-axis current I qand the d-axis voltage V applied to synchronous motor 2 d and q-axis voltage V q and the rotational position θ calculated by the position and speed calculation unit 36 e and the rotation speed ω, the induced voltage harmonic component e induced in the winding from the rotor of the synchronous motor 2 h and an induced voltage harmonic estimating unit 40 that estimates the induced voltage harmonic component e h to the amplitude of one component e qnhamp and phase ζ qnh and an induced voltage harmonic component extractor 42 that extracts the q-axis current I q Current harmonic components i included in qh The amplitude of one component from i qnhamp and phase δ qnh and a current harmonic component extractor 44 extracting the amplitude e of one of the components extracted by the induced voltage harmonic component extractor 42. qnhamp The amplitude command value I of the q-axis compensation current generated based on qnhamp The amplitude i of one component extracted by the current harmonic component extractor 44 is qnhamp and the phase ζ of one component extracted by the induced voltage harmonic component extractor 42 qnh The phase δ of one component extracted by the current harmonic component extractor 44 is qnh and a correction current generating unit 46 that generates a q-axis compensation current so as to match the

[0141] Such a control device 6 controls the induced voltage harmonic component e h and current harmonic components i qh Since the amplitude and phase are generated for each component extracted from the magnetic flux harmonic, a compensation current corresponding to a change in either the amplitude or phase of the magnetic flux harmonic can be generated. As a result, the control device 6 can achieve a high suppression effect on the pulsation of the rotating shaft generated in the synchronous motor 2.

[0142] In the control device 6 according to the present embodiment, the induced voltage harmonic component extracting unit 42b extracts the induced voltage harmonic component e extracted using a band-pass filter so as to match the rotation speed ω of the synchronous motor 2. qn Based on ', the induced voltage harmonic components eqn Search for the maximum and minimum amplitudes of ' and find the amplitude of one component e qnhamp The current harmonic component extractor 44b extracts the current harmonic component i that is extracted so as to match the rotation speed ω of the synchronous motor 2 using a bandpass filter. qnh Based on the current harmonic components i qnh Search for the maximum and minimum amplitudes of one component, i qnhamp Extract.

[0143] Such a control device 6 controls the induced voltage harmonic component e qn ' and current harmonic components i qnh By searching for the amplitude of the signal, the influence of errors due to signal disturbance can be reduced.

[0144] In the control device 6 according to the present embodiment, the induced voltage harmonic component extracting unit 42b extracts the induced voltage harmonic component e extracted using a band-pass filter so as to match the rotation speed ω of the synchronous motor 2. qn ', the phase of one component ζ qnh The current harmonic component extractor 44b extracts the current harmonic component i that is extracted so as to match the rotation speed ω of the synchronous motor 2 using a bandpass filter. qnh Based on the phase of one component, δ qnh Extract.

[0145] Such a control device 6 can reduce the influence of errors due to signal disturbances by not calculating specific values ​​of the phase.

[0146] In the control device 6 according to this embodiment, the induced voltage harmonic component extractor 42 extracts the induced voltage harmonic component e estimated by the induced voltage harmonic estimator 40. h , the induced voltage harmonic component e h Rotational position θ e Multiplying the sin and cos operators using qnhamp and phase ζ qnh Extract the following.

[0147] Such a control device 6 controls the induced voltage harmonic component eh Rotational position θ e Considering the induced voltage harmonic component e h The amplitude of one component extracted from qnhamp and phase ζ qnh Since the above-mentioned values ​​are extracted, it is possible to generate a compensation current that corresponds to more detailed changes.

[0148] In the control device 6 according to the present embodiment, the correction current generating unit 46a calculates the phase ζ of one of the components extracted by the induced voltage harmonic component extracting unit 42a. qnh is used as a phase command value, and the phase δ of one component extracted by the current harmonic component extractor 44a is qnh or the phase ζ of one component extracted by the induced voltage harmonic component extractor 42a. qnh and the phase δ of one component extracted by the current harmonic component extractor 44a. qnh The difference between these values ​​is calculated, and the difference is made to follow a predetermined command value.

[0149] Such a control device 6 controls the induced voltage harmonic component e h The phase of one component extracted from qnh and current harmonic component i qh The phase δ of one component extracted from qnh Since the above is combined, a compensation current corresponding to the change in phase of the magnetic flux harmonics can be generated.

[0150] Furthermore, in the control device 6 according to this embodiment, the compensation current generating unit 38 generates a plurality of q-axis compensation currents for each component of the pulsation of the rotating shaft occurring in the synchronous motor 2.

[0151] Such a control device 6 generates a plurality of compensation currents for each component of the pulsation of the rotating shaft occurring in the synchronous motor 2, and therefore can obtain a higher effect of suppressing the pulsation of the rotating shaft occurring in the synchronous motor 2.

[0152] In addition, the control method according to the present embodiment is also effective in reducing the rotation angle θ of the synchronous motor 2. m The output of the angle detector 4 that detects the rotational position θ of the rotor of the synchronous motor 2 is used to calculate the rotational position θ of the rotor of the synchronous motor 2. eand a position and speed calculation step (S105) for calculating the rotation speed ω, and a d-axis current command value I of the rotating coordinate system in vector control, which is output from the controller 10 that makes the synchronous motor 2 follow the rotation command value. d * and q-axis current command value I q * and a current command conversion step (S101) converting the three-phase current flowing through the synchronous motor 2 into the d-axis current I d and q-axis current I q and the uvw / dq conversion step (S106) converts the d-axis current command value I d * and d-axis current I d and the q-axis current command value I q * and q-axis current I q a control step (S103) of controlling the synchronous motor 2 based on the difference between the q-axis current command value I and the q-axis current command value I; a compensation current generation step (S110) of generating a q-axis compensation current that suppresses pulsation of the rotating shaft occurring in the synchronous motor 2; and a current command conversion step (S101) of converting the q-axis compensation current generated in the compensation current generation step (S110) into a q-axis current command value I q * and a compensation current generating step (S110) for generating a compensation current I d and q-axis current I d and the d-axis voltage V applied to synchronous motor 2 d and q-axis voltage V q and the rotational position θ calculated in the position and velocity calculation step (S105). e and the rotation speed ω, the induced voltage harmonic component e induced in the winding from the rotor of the synchronous motor 2 h and an induced voltage harmonic component e estimated in the induced voltage harmonic estimation step (S107). h to the amplitude of one component e qnhamp and phase ζ qnh and an induced voltage harmonic component extraction step (S108) for extracting the q-axis current I q Current harmonic components i included in qh The amplitude of one component from i qnhamp and phase δ qnhand the amplitude e of one component extracted in the induced voltage harmonic component extraction step (S108). qnhamp The amplitude command value I of the q-axis compensation current generated based on qnhamp The amplitude i of one component extracted in the current harmonic component extraction step (S109) qnhamp and the phase ζ of one component extracted in the induced voltage harmonic component extraction step (S108) qnh The phase δ of one component extracted in the current harmonic component extraction step (S109) qnh and a correction current generating step (S110) of generating a q-axis compensation current so as to match the q-axis compensation current.

[0153] This control method generates the amplitude and phase for one component extracted from the induced voltage harmonic components and one component extracted from the current harmonic components, and can generate a compensation current that corresponds to changes in either the amplitude or phase of the magnetic flux harmonics, thereby achieving a high effect of suppressing pulsation of the rotating shaft occurring in the synchronous motor 2.

[0154] The control algorithm of the present invention also allows a digital processor or integrated electronic circuit to implement the control method of the present invention.

[0155] Such a digital processor or integrated electronic circuit provides the same effects as the control method according to the present embodiment.

[0156] (Embodiment 2) A system including a control device 6a according to a second embodiment, which is configured by partially modifying the system including the control device 6 according to the first embodiment, will be described below with reference to FIG. 7. FIG. 7 is a block diagram showing the configuration of a system including a control device according to the second embodiment. Of the system including the control device 6a according to the second embodiment shown in FIG. 7, components that are similar to those in the system including the control device 6 according to the first embodiment will be assigned the same reference numerals and will not be described again, as they have already been described. The following description will focus on differences from the system including the control device 6 according to the first embodiment. Note that the system including the control device 6a according to the second embodiment differs from the system including the control device 6 according to the first embodiment in that it does not include an angle detector 4 and that the control device 6a includes a position and speed estimation unit 90 instead of the position and speed calculation unit 36.

[0157] [Control device configuration] The position and speed estimation unit 90 estimates the d-axis voltage V d and the q-axis voltage V output by the controller 22. q and the d-axis current I output by the uvw / dq conversion unit 34. d and q-axis current I q Based on this, the rotational position θ of the rotor of the synchronous motor 2 is calculated. e and the rotation speed ω.

[0158] The dq / uvw conversion unit 24 converts the rotational position θ e Based on this, the d-axis voltage V d and the q-axis voltage V q and the U phase voltage V u and V phase voltage V v and W-phase voltage V w The uvw / dq conversion unit 34 converts the rotational position θ e Based on this, the three-phase current (i.e., U-phase current I u and V-phase current I v and W-phase current I w and ) is the d-axis current I d and q-axis current I q Convert to.

[0159] The compensation current generator 38 also generates a d-axis voltage V d and the q-axis voltage V output by the controller 22. q and the d-axis current I output by the uvw / dq conversion unit 34. d and q-axis current I q and the rotational position θ output by the position and speed estimation unit 90. e and the rotation speed ω, the nth-order compensation current I qnh The compensation current generating unit 38 generates the rotational position θ e Without obtaining the rotational speed ω, the rotational position θ e may be calculated.

[0160] [Control device operation] Next, an operation performed by the control device 6a according to the second embodiment to suppress pulsation of the rotating shaft occurring in the synchronous motor 2 will be described with reference to Fig. 8. Fig. 8 is a flowchart showing the operation performed by the control device 6a according to the second embodiment. Note that steps S201 to S204, step S206, and steps S208 to S210 shown in Fig. 8 are the same as steps S101 to S104, step S106, and steps S108 to S110 shown in Fig. 5, and therefore description thereof will be omitted.

[0161] The position and speed estimation unit 90 estimates the d-axis voltage V d and the q-axis voltage V output by the controller 22. q and the d-axis current I output by the uvw / dq conversion unit 34. d and q-axis current I q Based on this, the rotational position θ of the rotor of the synchronous motor 2 is calculated. e and the rotation speed ω are estimated (step S205).

[0162] The induced voltage harmonic estimation unit 40 estimates the d-axis voltage V d and the q-axis voltage V output by the controller 22. q and the d-axis current I output by the uvw / dq conversion unit 34. d and q-axis current I qand the rotational position θ output by the position and speed estimation unit 90. e Based on the rotation speed ω and ω, the induced voltage harmonic component e h In step S207, the induced voltage harmonic estimator 40 receives the rotational position θ e Without obtaining the rotational speed ω, the rotational position θ e may be calculated.

[0163] From the above explanation, the control device 6a can detect the induced voltage harmonic component e h and current harmonic components i qh Since the amplitude and phase are generated for each component extracted from, it is possible to generate a compensation current corresponding to a change in either the amplitude or phase of the magnetic flux harmonic.

[0164] Furthermore, the control device 6a detects the rotational position θ of the rotor of the synchronous motor 2 without using a position sensor. e and the rotation speed ω are estimated, it is possible to detect the pulsation of the rotating shaft occurring in the synchronous motor 2 with a simpler configuration than when a position sensor is used.

[0165] [Modification of the control device] Fig. 9 is a block diagram showing a modified example of the control device 6a according to embodiment 2. The control device 6a shown in Fig. 9 differs from the control device 6a shown in Fig. 7 in that it includes two adders 18a, 18b and two compensation current generators 38a, 38b.

[0166] As a result, the control device 6a generates a plurality of compensation currents for each component of the pulsation of the rotating shaft occurring in the synchronous motor 2, and therefore, a higher effect of suppressing the pulsation of the rotating shaft occurring in the synchronous motor 2 can be obtained.

[0167] In the explanation of FIG. 9, a modified example in which the control device 6a includes two adders 18a, 18b and two compensation current generators 38a, 38b has been described, but the control device 6a may include three or more adders and three or more compensation current generators.

[0168] [effect] As described above, the control device 6a according to this embodiment can detect the rotational position θ of the rotor of the synchronous motor 2. e and a position and speed estimating unit 90 that estimates the rotation speed ω, and a controller 10 that makes the output of the synchronous motor 2 follow the rotation command value, and converts the output of the controller 10 into a d-axis current command value I d * and q-axis current command value I q * and a current command conversion unit 12 converting the three-phase current flowing through the synchronous motor 2 into a d-axis current I d and q-axis current I q and a uvw / dq conversion unit 34 converting the d-axis current command value I d * and d-axis current I d and the q-axis current command value I q * and q-axis current I q a compensation current generating unit 38 that generates a q-axis compensation current that suppresses pulsation of the rotating shaft occurring in the synchronous motor 2; and a q-axis current command value I q * and an adder 18 that adds a d-axis current I d and q-axis current I q and the d-axis voltage V applied to synchronous motor 2 d and q-axis voltage V q and the rotational position θ estimated by the position and speed estimation unit 90 e and the rotation speed ω, the induced voltage harmonic component e induced in the winding from the rotor of the synchronous motor 2 h and an induced voltage harmonic estimating unit 40 that estimates the induced voltage harmonic component e h to the amplitude of one component e qnhamp and phase ζ qnh and an induced voltage harmonic component extractor 42 that extracts the q-axis current I q Current harmonic components i included in qh The amplitude of one component from i qnhamp and phase δ qnhand a current harmonic component extractor 44 extracting the amplitude e of one of the components extracted by the induced voltage harmonic component extractor 42. qnhamp The amplitude command value I of the q-axis compensation current generated based on qnhamp The amplitude i of one component extracted by the current harmonic component extractor 44 is qnhamp and the phase ζ of one component extracted by the induced voltage harmonic component extractor 42 qnh The phase δ of one component extracted by the current harmonic component extractor 44 is qnh and a correction current generating unit 46 that generates a q-axis compensation current so as to match the

[0169] Such a control device 6a controls the induced voltage harmonic component e h and current harmonic components i qh Since the amplitude and phase are generated for each component extracted from the magnetic flux harmonic, a compensation current corresponding to a change in either the amplitude or phase of the magnetic flux harmonic can be generated. As a result, the control device 6a can effectively suppress the pulsation of the rotating shaft generated in the synchronous motor 2.

[0170] Furthermore, the control device 6a detects the rotational position θ of the rotor of the synchronous motor 2 without using a position sensor. e and the rotation speed ω are estimated, it is possible to detect the pulsation of the rotating shaft occurring in the synchronous motor 2 with a simpler configuration than when a position sensor is used.

[0171] Moreover, in the control device 6a according to this embodiment, the compensation current generating unit 38 generates a plurality of q-axis compensation currents for each component of the pulsation of the rotating shaft occurring in the synchronous motor 2.

[0172] Such a control device 6a generates a plurality of compensation currents for each component of the pulsation of the rotating shaft occurring in the synchronous motor 2, and therefore can obtain a higher effect of suppressing the pulsation of the rotating shaft occurring in the synchronous motor 2.

[0173] In addition, the control method according to the present embodiment is also for controlling the rotational position θ of the rotor of the synchronous motor 2. eand rotational speed ω; a current command conversion step of converting the output of the controller 10 that follows the rotation command value of the synchronous motor 2 into a d-axis current command value and a q-axis current command value of the rotating coordinate system in vector control; and a current command conversion step of converting the output of the controller 10 that follows the rotation command value of the synchronous motor 2 into a d-axis current command value I d * and q-axis current command value I q * and a current command conversion step (S201) converting the three-phase current flowing through the synchronous motor 2 into the d-axis current I d and q-axis current I q and the uvw / dq conversion step (S206) converts the d-axis current command value I d * and d-axis current I d and the q-axis current command value I q * and q-axis current I q a control step (S203) of controlling the synchronous motor 2 based on the difference between the q-axis current command value I and the q-axis current command value I; a compensation current generation step (S210) of generating a q-axis compensation current that suppresses pulsation of the rotating shaft occurring in the synchronous motor 2; and a current command conversion step (S201) of converting the q-axis compensation current generated in the compensation current generation step (S210) into the q-axis current command value I q * and a compensation current generating step (S210) for generating a compensation current based on the d-axis current I d and q-axis current I q and the d-axis voltage V applied to synchronous motor 2 d and q-axis voltage V q and the rotational position θ estimated in the position and speed estimation step (S205). e and the rotation speed ω, the induced voltage harmonic component e induced in the winding from the rotor of the synchronous motor 2 h and an induced voltage harmonic component e estimated in the induced voltage harmonic estimation step (S207). h to the amplitude of one component e qnhamp and phase ζ qnh and an induced voltage harmonic component extraction step (S208) for extracting the q-axis current I qCurrent harmonic components i included in qh The amplitude of one component from i qnhamp and phase δ qnh and the amplitude e of one component extracted in the induced voltage harmonic component extraction step (S208). qnhamp The amplitude command value I of the q-axis compensation current generated based on qnhamp The amplitude i of one component extracted in the current harmonic component extraction step (S209) qnhamp and the phase ζ of one component extracted in the induced voltage harmonic component extraction step (S208) qnh The phase δ of one component extracted in the current harmonic component extraction step (S209) qnh and a correction current generating step (S210) of generating a q-axis compensation current so as to match the q-axis compensation current.

[0174] This control method generates the amplitude and phase for one component extracted from the induced voltage harmonic components and one component extracted from the current harmonic components, and can generate a compensation current that corresponds to changes in either the amplitude or phase of the magnetic flux harmonics, thereby achieving a high effect of suppressing pulsation of the rotating shaft occurring in the synchronous motor 2.

[0175] Furthermore, this control method does not use a position sensor, but detects the rotational position θ of the rotor of the synchronous motor 2. e and the rotation speed ω are estimated, it is possible to detect the pulsation of the rotating shaft occurring in the synchronous motor 2 with a simpler configuration than when a position sensor is used.

[0176] The control algorithm of the present invention also allows a digital processor or integrated electronic circuit to implement the control method of the present invention.

[0177] Such a digital processor or integrated electronic circuit provides the same effects as the control method according to the present embodiment.

[0178] [Variations] Although the control device and the like according to the present disclosure have been described above based on the above-described embodiment, the present disclosure is not limited to the above-described embodiment. As long as they do not deviate from the spirit of the present disclosure, various modifications conceivable by those skilled in the art to the above-described embodiment and configurations constructed by combining components of different embodiments may also be included within the scope of one or more aspects.

[0179] Furthermore, the control algorithm according to the present disclosure may be realized, for example, as a program that causes a digital processor or an integrated electronic circuit to execute the control method according to the present disclosure.

[0180] In the above embodiments, each component may be configured with dedicated hardware, or may be realized by executing a software program suitable for each component. Each component may be realized by a program execution unit such as a CPU or processor reading and executing a software program recorded on a recording medium such as a hard disk or semiconductor memory.

[0181] In the above-described embodiments, some or all of the functions of the components may be realized by a processor such as a CPU executing a program.

[0182] Some or all of the components constituting each of the above devices may be configured as an IC card or a standalone module that can be attached to or detached from each device. The above IC card or module is a computer system composed of a microprocessor, ROM, RAM, etc. The above IC card or module may include a super multi-function LSI. The above IC card or module achieves its functions when the microprocessor operates according to a computer program. The IC card or module may be tamper-resistant.

[0183] [Note] The above description of the embodiments discloses the following techniques.

[0184] (Technology 1) A synchronous motor includes a position and speed calculation unit that calculates a rotational position and a rotational speed of a rotor of the synchronous motor using the output of an angle detector that detects the rotation angle of the synchronous motor; a current command conversion unit that converts the output of a controller that makes the synchronous motor follow a rotational speed command value into a d-axis current command value and a q-axis current command value of a rotating coordinate system in vector control; a UVW / DQ conversion unit that converts three-phase currents flowing through the synchronous motor into d-axis currents and q-axis currents of the rotating coordinate system; an inverter that controls the synchronous motor based on the difference between the d-axis current command value and the d-axis current and the difference between the q-axis current command value and the q-axis current; a compensation current generation unit that generates a q-axis compensation current that suppresses pulsation of a rotating shaft generated in the synchronous motor; and an adder that superimposes the q-axis compensation current generated by the compensation current generation unit on the q-axis current command value converted by the current command conversion unit, an induced voltage harmonic estimating unit that estimates induced voltage harmonic components induced in a winding from the rotor of the synchronous motor based on the applied d-axis voltage and q-axis voltage and the rotational position and the rotational speed calculated by the position and speed calculating unit; an induced voltage harmonic component extracting unit that extracts the amplitude and phase of one component from the induced voltage harmonic components estimated by the induced voltage harmonic estimating unit; and an induced voltage harmonic component extracting unit that extracts the amplitude and phase of one component from current harmonic components included in the q-axis current. a current harmonic component extraction unit; and a correction current creation unit that generates the q-axis compensation current so that the amplitude of the one component extracted by the current harmonic component extraction unit matches an amplitude command value of the q-axis compensation current generated based on the amplitude of the one component extracted by the induced voltage harmonic component extraction unit, and so that the phase of the one component extracted by the current harmonic component extraction unit matches a phase of the one component extracted by the induced voltage harmonic component extraction unit.

[0185] (Technology 2) A synchronous motor includes a position and speed estimation unit that estimates the rotational position and rotational speed of a rotor of the synchronous motor, a current command conversion unit that converts the output of a controller that makes the synchronous motor follow a rotational speed command value into a d-axis current command value and a q-axis current command value of a rotating coordinate system in vector control, a uvw / dq conversion unit that converts a three-phase current flowing through the synchronous motor into a d-axis current and a q-axis current of the rotating coordinate system, an inverter that controls the synchronous motor based on the difference between the d-axis current command value and the d-axis current and the difference between the q-axis current command value and the q-axis current, a compensation current generation unit that generates a q-axis compensation current that suppresses rotating shaft pulsation of the synchronous motor, and an adder that superimposes the q-axis compensation current generated by the compensation current generation unit on the q-axis current command value converted by the current command conversion unit, and the compensation current generation unit converts the d-axis current, the q-axis current, and the d-axis voltage and q-axis voltage applied to the synchronous motor into a d-axis current and a q-axis current. a current harmonic component extraction unit that extracts the amplitude and phase of one component from current harmonic components included in the q-axis current; and a correction current creation unit that generates the q-axis compensation current so that the amplitude of the one component extracted by the current harmonic component extraction unit matches an amplitude command value of the q-axis compensation current generated based on the amplitude of the one component extracted by the induced voltage harmonic component extraction unit and so that the phase of the one component extracted by the current harmonic component extraction unit matches a phase of the one component extracted by the induced voltage harmonic component extraction unit.

[0186] (Technology 3) The control device according to Technology 1 or 2, wherein the induced voltage harmonic component extraction unit searches for a maximum value of the amplitude of the induced voltage harmonic component based on the induced voltage harmonic component extracted using a band-pass filter so as to match the rotation speed of the synchronous motor, and extracts the amplitude of the one component, and the current harmonic component extraction unit searches for a maximum value of the amplitude of the current harmonic component based on the current harmonic component extracted using a band-pass filter so as to match the rotation speed of the synchronous motor, and extracts the amplitude of the one component.

[0187] (Technology 4) The control device according to any one of Technologies 1 to 3, wherein the induced voltage harmonic component extraction unit extracts the phase of the one component based on the induced voltage harmonic component extracted using a band-pass filter so as to match the rotation speed of the synchronous motor, and the current harmonic component extraction unit extracts the phase of the one component based on the current harmonic component extracted using a band-pass filter so as to match the rotation speed of the synchronous motor.

[0188] (Technology 5) The control device according to Technology 1 or 2, wherein the induced voltage harmonic component extraction unit multiplies the induced voltage harmonic component estimated by the induced voltage harmonic estimation unit by sin and cos operators using the rotational position of the induced voltage harmonic component, to extract the amplitude and phase of the one component.

[0189] (Technology 6) The control device according to any one of Technologies 1 to 5, wherein the correction current creation unit uses the phase of the one component extracted by the induced voltage harmonic component extraction unit as a phase command value to make it follow the phase of the one component extracted by the current harmonic component extraction unit, or calculates the difference between the phase of the one component extracted by the induced voltage harmonic component extraction unit and the phase of the one component extracted by the current harmonic component extraction unit, and makes the difference follow a predetermined command value.

[0190] (Technology 7) The control device according to any one of Technologies 1 to 6, wherein the compensation current generating unit generates a plurality of the q-axis compensation currents for each component of pulsation of the rotating shaft occurring in the synchronous motor.

[0191] (Technology 8) A method for controlling a synchronous motor includes a position and speed calculation step of calculating a rotational position and a rotational speed of a rotor of the synchronous motor using an output of an angle detector that detects a rotation angle of the synchronous motor; a current command conversion step of converting an output of a controller that makes the synchronous motor follow a rotation command value into a d-axis current command value and a q-axis current command value of a rotating coordinate system in vector control; a uvw / dq conversion step of converting three-phase currents flowing through the synchronous motor into d-axis currents and q-axis currents of the rotating coordinate system; a control step of controlling the synchronous motor based on a difference between the d-axis current command value and the d-axis current and a difference between the q-axis current command value and the q-axis current; a compensation current generation step of generating a q-axis compensation current that suppresses pulsation of a rotating shaft generated in the synchronous motor; and an addition step of superimposing the q-axis compensation current generated in the compensation current generation step on the q-axis current command value converted in the current command conversion step, an induced voltage harmonic estimation step of estimating induced voltage harmonic components induced in a winding from the rotor of the synchronous motor based on the d-axis voltage and q-axis voltage calculated in the position and speed calculation step and the rotational position and the rotational speed calculated in the position and speed calculation step; an induced voltage harmonic component extraction step of extracting the amplitude and phase of one component from the induced voltage harmonic components estimated in the induced voltage harmonic estimation step; and a current harmonic extraction step of extracting the amplitude and phase of one component from current harmonic components included in the q-axis current. a harmonic component extraction step; and a correction current creation step of generating the q-axis compensation current so that the amplitude of the one component extracted in the current harmonic component extraction step matches an amplitude command value of the q-axis compensation current generated based on the amplitude of the one component extracted in the induced voltage harmonic component extraction step, and so that the phase of the one component extracted in the current harmonic component extraction step matches a phase of the one component extracted in the induced voltage harmonic component extraction step.

[0192] (Technology 9) A method for controlling a synchronous motor includes a position and speed estimation step of estimating a rotation position and a rotation speed of a rotor of a synchronous motor, a current command conversion step of converting an output of a controller that makes the output of the synchronous motor follow a rotation command value into a d-axis current command value and a q-axis current command value of a rotating coordinate system in vector control, a uvw / dq conversion step of converting a three-phase current flowing through the synchronous motor into a d-axis current and a q-axis current of the rotating coordinate system, a control step of controlling the synchronous motor based on a difference between the d-axis current command value and the d-axis current and a difference between the q-axis current command value and the q-axis current, a compensation current generation step of generating a q-axis compensation current that suppresses rotating shaft pulsation of the synchronous motor, and an addition step of superimposing the q-axis compensation current generated in the compensation current generation step on the q-axis current command value converted in the current command conversion step, and the compensation current generation step is performed by converting the d-axis current, the q-axis current, the d-axis voltage and the q-axis voltage applied to the synchronous motor, and the position command value. a induced voltage harmonic estimation step of estimating induced voltage harmonic components induced in a winding from the rotor of the synchronous motor based on the rotational position and the rotational speed estimated in the rotor speed estimation step; a induced voltage harmonic component extraction step of extracting an amplitude and a phase of one component from the induced voltage harmonic components estimated in the induced voltage harmonic estimation step; a current harmonic component extraction step of extracting an amplitude and a phase of one component from current harmonic components included in the q-axis current; and a correction current generation step of generating the q-axis compensation current so that the amplitude of the one component extracted in the current harmonic component extraction step matches an amplitude command value of the q-axis compensation current generated based on the amplitude of the one component extracted in the induced voltage harmonic component extraction step and so that the phase of the one component extracted in the current harmonic component extraction step matches the phase of the one component extracted in the induced voltage harmonic component extraction step.

[0193] (Technology 10) A method for causing a digital processor or an integrated electronic circuit to execute the control method described in Technology 8 or 9. [Industrial Applicability]

[0194] A control device according to the present disclosure is useful, for example, as a device that controls a current to a synchronous motor to generate a target torque. [Explanation of symbols]

[0195] 2 synchronous motor 4 Angle detector 6, 6a Control device 8, 14, 20, 64, 68, 68a differentiator 10, 16, 22 Controller 12 Current command conversion unit 18, 18a, 18b Addition section 24 dq / uvw conversion section 26 inverter 28 First current sensor 30 Second current sensor 32 Third current sensor 34 UVW / DQ conversion section 36 Position speed calculation section 38, 38a, 38b Compensation current generation section 40 Induced voltage harmonic estimation section 42, 42a, 42b Induced voltage harmonic component extraction section 44, 44a, 44b Current harmonic component extraction section 46, 46a Correction current generating section 48, 48b, 58, 58b n-dimensional component extraction section 50, 60 Amplitude calculation section 52 Compensation current amplitude calculation section 54, 62 Phase calculation section 56, 80 Low-pass filter 66, 70 PI controller 72, 78 Arithmetic section 74, 76 Phase synthesis section 82, 86 Amplitude search section 84, 88 Signal generation unit 90 Position speed estimation section

Claims

1. a position and speed calculation unit that calculates a rotational position and a rotational speed of a rotor of the synchronous motor using an output of an angle detector that detects a rotational angle of the synchronous motor; a current command conversion unit that converts an output of a controller that causes the output to follow a rotational speed command value of the synchronous motor into a d-axis current command value and a q-axis current command value of a rotating coordinate system in vector control; a uvw / dq conversion unit that converts the three-phase current flowing through the synchronous motor into a d-axis current and a q-axis current of the rotating coordinate system; an inverter that controls the synchronous motor based on a difference between the d-axis current command value and the d-axis current and a difference between the q-axis current command value and the q-axis current; a compensation current generating unit that generates a q-axis compensation current that suppresses pulsation of a rotating shaft generated in the synchronous motor; an adder that superimposes the q-axis compensation current generated by the compensation current generator on the q-axis current command value converted by the current command converter, The compensation current generating unit an induced voltage harmonic estimating unit that estimates induced voltage harmonic components induced in a winding from the rotor of the synchronous motor based on the d-axis current, the q-axis current, the d-axis voltage and the q-axis voltage applied to the synchronous motor, and the rotational position and the rotational speed calculated by the position and speed calculating unit; an induced voltage harmonic component extracting unit that extracts the amplitude and phase of one component from the induced voltage harmonic components estimated by the induced voltage harmonic estimating unit; a current harmonic component extractor that extracts the amplitude and phase of one component from the current harmonic components included in the q-axis current; a correction current generating unit that generates the q-axis compensation current so that the amplitude of the one component extracted by the current harmonic component extracting unit coincides with an amplitude command value of the q-axis compensation current generated based on the amplitude of the one component extracted by the induced voltage harmonic component extracting unit, and so that the phase of the one component extracted by the current harmonic component extracting unit coincides with the phase of the one component extracted by the induced voltage harmonic component extracting unit. Control device.

2. a position and speed estimation unit that estimates the rotational position and rotational speed of a rotor of the synchronous motor; a current command conversion unit that converts an output of a controller that causes the output to follow a rotational speed command value of the synchronous motor into a d-axis current command value and a q-axis current command value of a rotating coordinate system in vector control; a uvw / dq conversion unit that converts the three-phase current flowing through the synchronous motor into a d-axis current and a q-axis current of the rotating coordinate system; an inverter that controls the synchronous motor based on a difference between the d-axis current command value and the d-axis current and a difference between the q-axis current command value and the q-axis current; a compensation current generating unit that generates a q-axis compensation current that suppresses rotational shaft pulsation of the synchronous motor; an adder that superimposes the q-axis compensation current generated by the compensation current generator on the q-axis current command value converted by the current command converter, The compensation current generating unit an induced voltage harmonic estimating unit that estimates induced voltage harmonic components induced in a winding from the rotor of the synchronous motor based on the d-axis current, the q-axis current, the d-axis voltage and the q-axis voltage applied to the synchronous motor, and the rotational position and the rotational speed estimated by the position / speed estimating unit; an induced voltage harmonic component extracting unit that extracts the amplitude and phase of one component from the induced voltage harmonic components estimated by the induced voltage harmonic estimating unit; a current harmonic component extractor that extracts the amplitude and phase of one component from the current harmonic components included in the q-axis current; a correction current generating unit that generates the q-axis compensation current so that the amplitude of the one component extracted by the current harmonic component extracting unit coincides with an amplitude command value of the q-axis compensation current generated based on the amplitude of the one component extracted by the induced voltage harmonic component extracting unit, and so that the phase of the one component extracted by the current harmonic component extracting unit coincides with the phase of the one component extracted by the induced voltage harmonic component extracting unit. Control device.

3. the induced voltage harmonic component extraction unit searches for a maximum value of the amplitude of the induced voltage harmonic component based on the induced voltage harmonic component extracted using a band-pass filter so as to match the rotation speed of the synchronous motor, and extracts the amplitude of the one component; the current harmonic component extraction unit searches for a maximum value of the amplitude of the current harmonic component based on the current harmonic component extracted using a band-pass filter so as to match the rotation speed of the synchronous motor, and extracts the amplitude of the one component. The control device according to claim 1 or 2.

4. the induced voltage harmonic component extracting unit extracts a phase of the one component based on the induced voltage harmonic components extracted using a band-pass filter so as to match the rotation speed of the synchronous motor; the current harmonic component extraction unit extracts a phase of the one component based on the current harmonic components extracted using a band-pass filter so as to match the rotation speed of the synchronous motor; The control device according to claim 1 or 2.

5. the induced voltage harmonic component extraction unit multiplies the induced voltage harmonic component estimated by the induced voltage harmonic estimation unit by sin and cos operators using a rotational position of the induced voltage harmonic component to extract an amplitude and a phase of the one component; The control device according to claim 1 or 2.

6. the correction current creation unit uses the phase of the one component extracted by the induced voltage harmonic component extraction unit as a phase command value and makes it follow the phase of the one component extracted by the current harmonic component extraction unit, or calculates a difference between the phase of the one component extracted by the induced voltage harmonic component extraction unit and the phase of the one component extracted by the current harmonic component extraction unit, and makes the difference follow a predetermined command value. The control device according to claim 1 or 2.

7. the compensation current generating unit generates a plurality of q-axis compensation currents for each component of pulsation of the rotating shaft occurring in the synchronous motor. The control device according to claim 1 or 2.

8. a position and speed calculation step of calculating a rotational position and a rotational speed of a rotor of the synchronous motor using an output of an angle detector that detects a rotation angle of the synchronous motor; a current command conversion step of converting an output of a controller that follows a rotation command value of the synchronous motor into a d-axis current command value and a q-axis current command value of a rotating coordinate system in vector control; a uvw / dq transformation step of transforming the three-phase currents flowing through the synchronous motor into d-axis currents and q-axis currents in the rotating coordinate system; a control step of controlling the synchronous motor based on a difference between the d-axis current command value and the d-axis current and a difference between the q-axis current command value and the q-axis current; a compensation current generating step of generating a q-axis compensation current that suppresses pulsation of a rotating shaft occurring in the synchronous motor; an adding step of superimposing the q-axis compensation current generated in the compensation current generating step on the q-axis current command value converted in the current command converting step, The compensation current generating step includes: an induced voltage harmonic estimation step of estimating induced voltage harmonic components induced in a winding from the rotor of the synchronous motor based on the d-axis current, the q-axis current, the d-axis voltage and the q-axis voltage applied to the synchronous motor, and the rotational position and the rotational speed calculated in the position and speed calculation step; an induced voltage harmonic component extraction step of extracting the amplitude and phase of one component from the induced voltage harmonic components estimated in the induced voltage harmonic estimation step; a current harmonic component extraction step of extracting the amplitude and phase of one component from the current harmonic components included in the q-axis current; a correction current generating step of generating the q-axis compensation current so that the amplitude of the one component extracted in the current harmonic component extracting step is matched to an amplitude command value of the q-axis compensation current generated based on the amplitude of the one component extracted in the induced voltage harmonic component extracting step, and so that the phase of the one component extracted in the current harmonic component extracting step is matched to the phase of the one component extracted in the induced voltage harmonic component extracting step. Control method.

9. a position and speed estimation step of estimating a rotational position and a rotational speed of a rotor of the synchronous motor; a current command conversion step of converting an output of a controller that follows a rotation command value of the synchronous motor into a d-axis current command value and a q-axis current command value of a rotating coordinate system in vector control; a uvw / dq transformation step of transforming the three-phase currents flowing through the synchronous motor into d-axis currents and q-axis currents in the rotating coordinate system; a control step of controlling the synchronous motor based on a difference between the d-axis current command value and the d-axis current and a difference between the q-axis current command value and the q-axis current; a compensation current generating step of generating a q-axis compensation current for suppressing rotation shaft pulsation of the synchronous motor; an adding step of superimposing the q-axis compensation current generated in the compensation current generating step on the q-axis current command value converted in the current command converting step, The compensation current generating step includes: an induced voltage harmonic estimation step of estimating induced voltage harmonic components induced in a winding from the rotor of the synchronous motor based on the d-axis current, the q-axis current, the d-axis voltage and the q-axis voltage applied to the synchronous motor, and the rotational position and the rotational speed estimated in the position / speed estimation step; an induced voltage harmonic component extraction step of extracting the amplitude and phase of one component from the induced voltage harmonic components estimated in the induced voltage harmonic estimation step; a current harmonic component extraction step of extracting the amplitude and phase of one component from the current harmonic components included in the q-axis current; a correction current generating step of generating the q-axis compensation current so that the amplitude of the one component extracted in the current harmonic component extracting step is matched to an amplitude command value of the q-axis compensation current generated based on the amplitude of the one component extracted in the induced voltage harmonic component extracting step, and so that the phase of the one component extracted in the current harmonic component extracting step is matched to the phase of the one component extracted in the induced voltage harmonic component extracting step. Control method.

10. 10. A control method according to claim 8 or 9, which is carried out by a digital processor or an integrated electronic circuit.

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