JP2005080458A - Motor controlling device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor controlling device that makes it possible to start a motor smoothly, when it is started from the state that a permanent magnet motor is rotating. <P>SOLUTION: When a slip determining means 18 determines immediately after a start that the motor is rotating, a presumed gain by a rotor position presuming means 15 is increased to quicken presuming response until the DC component of a value, obtained by subtracting the product of a d-axis voltage high-frequency component and a d-axis current high-frequency component from that of a q-axis voltage high-frequency component and a q-axis current high-frequency component calculated by the rotor position presuming means 15, converges into a prescribed range. The presuming gain is returned to a normal state after the conversion of the DC component into the prescribed range. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a control device for a permanent magnet motor.

  2. Description of the Related Art Conventionally, there has been known a motor control device that uses a magnetic special polarity of a permanent magnet motor rotor to grasp a rotor position (see, for example, Patent Document 1), and a configuration example thereof is shown in FIG.

  As shown in FIG. 6, the motor control device includes high-frequency current command superimposing means 11, current control means 12, voltage command coordinate conversion means 13, current coordinate conversion means 14, and rotor position estimation means 15. And applied to the inverter unit 2 that drives the permanent magnet motor 1.

  The high-frequency current superimposing means 11 superimposes a rotational current command having a high-frequency component different from the rotational frequency of the motor rotor of the motor 1 on the d-axis current command and the q-axis current commands IdRef1, IqRef1 necessary for outputting torque. . Here, the q axis is the rotor protrusion direction, and the d axis is a direction perpendicular to the rotor protrusion direction.

  The current control unit 12 outputs the current command values IdRef2 and IqRef2 output from the high-frequency current command superimposing unit 11 based on the actual values Id and Iq of the d-axis current and the q-axis current of the motor 1 which are outputs from the current coordinate conversion unit 14. The d-axis voltage command and the q-axis voltage command of the output of the inverter 2 are manipulated so as to follow.

  The voltage command coordinate conversion means 13 uses the d-axis voltage command and the q-axis voltage commands VdRef and VqRef, which are outputs from the current control means 12, and the estimated position θh of the motor rotor, which is an output from the rotor position estimation means 15. Is converted into a three-phase voltage command Vu, Vv, Vw of the inverter 2 and given to the inverter unit 2.

  The current coordinate conversion means 14 uses the three-phase currents (current detection values of two phases out of three phases) Iu and Iw of the motor 1 and the estimated position value θh of the motor rotor, which is the output from the rotor position estimation means 15. And converted into actual values Id and Iq of the d-axis current and the q-axis current, which are values on the dq coordinate axis.

The rotor position estimator 15 performs actual processing of the d-axis voltage command and q-axis voltage commands VdRef and VqRef output from the current controller 12 and the d-axis current and q-axis current output from the current coordinate converter 14. Using the values Id and Iq, the frequency component of the high-frequency current superimposed by the high-frequency current command superimposing means 11 of each input value is extracted by the bandpass filter (BPF) 15a, and the q-axis voltage high-frequency component and q A product of the axial current high frequency component is obtained by the multiplier 15b, a value obtained by subtracting the product of the d axis voltage high frequency component and the d axis current high frequency component from this product is calculated, and the DC component H of this calculated value becomes zero. In this way, the estimated rotational speed value ωh of the motor rotor is corrected by the PI controller 15c and output, and the time integral value of the estimated rotational speed value of the motor rotor is obtained by the integrator 15d. And outputs as the position estimate θh of the motor rotor.
JP 2001-339999 A

  However, since the gain of the PI controller 15c is fixed in the rotor position estimation means 15 in the above-described conventional apparatus, the rotor position estimation means 15 is activated when the permanent magnet motor 1 is started from the rotating state. If the control gain for estimating the rotor position at is low, the estimated value may not converge. In such a case, current control becomes unstable, undesired torque is generated, and in the worst case, restart is impossible due to an overcurrent protection operation.

  An object of the present invention is to provide a motor control device that can start smoothly when a permanent magnet motor starts from a rotating state.

In order to solve the above problems, the present invention provides a motor control device applied to a permanent magnet motor having a magnetic saliency in a motor rotor and supplied with an output from an inverter that converts DC power into AC power. ,
A rotational current command having a high frequency component different from the rotational frequency of the motor rotor, a d-axis current command related to the rotor projecting direction necessary for outputting torque, and a q-axis current command related to a direction perpendicular to the rotor projecting direction High frequency current command superimposing means for superimposing each on
The d-axis voltage command and q-axis voltage command of the inverter output are operated so that the actual values of the d-axis current and q-axis current of the motor follow the current command value output from the high-frequency current command superimposing means. Current control means;
Using the actual values of the d-axis voltage command, the q-axis voltage command, the d-axis current, and the q-axis current, the frequency component of the high-frequency current superimposed by the high-frequency current command superimposing means for each input value is extracted, and A value obtained by subtracting the product of the d-axis voltage high-frequency component and the d-axis current high-frequency component from the product of the q-axis voltage high-frequency component and the q-axis current high-frequency component is calculated, and the direct current component of the calculated value is zero. A rotor position estimating means for correcting and outputting the estimated rotational speed value of the rotor, and outputting a time integral value of the estimated rotational speed value of the motor rotor as the estimated position value of the motor rotor;
Voltage command coordinate conversion for converting a d-axis voltage command and a q-axis voltage command, which are outputs from the current control unit, into a three-phase voltage command using the estimated position value of the motor rotor by the rotor position estimation unit Means,
Current coordinate conversion means for converting the three-phase current of the motor into the d-axis current and the q-axis current, which are values on the dq-axis coordinate axes, using the estimated position of the motor rotor;
Immediately after start-up, current feedback control is performed so that the current flowing into the motor becomes a desired value including zero. When the output voltage command at this time exceeds a predetermined amount, the motor is rotating. An idling determination means for determining that there is,
If the idling determination means determines that the motor is rotating immediately after start-up, the d-axis voltage high-frequency component is calculated from the product of the q-axis voltage high-frequency component and the q-axis current high-frequency component calculated by the rotor position estimation means. Until the DC component of the value obtained by subtracting the product of the high-frequency component and the d-axis current converges within the predetermined range, the estimated gain of the rotor position estimating means is increased to speed up the estimation response, and the DC component is within the predetermined range. And control means for returning the estimated gain to the normal state after the convergence.

  According to the present invention, only current feedback control with a current reference of 0 is performed for a certain time from the start, and if the voltage vector amplitude during that time is greater than or equal to a certain value, it is determined that the permanent magnet motor is idling. By increasing the rotor position estimation gain at the time of harmonic superposition and performing position estimation at a high speed, the permanent magnet motor can be started smoothly even when the permanent magnet motor is rotating at a high speed.

  As described above, according to the present invention, it is possible to provide a motor control device that can start smoothly when the permanent magnet motor starts from a rotating state.

(First embodiment)
The motor control apparatus of 1st Embodiment by this invention is demonstrated with reference to FIG.1 and FIG.2. In FIG. 1, the same circuit elements as those in FIG. 6 are denoted by the same reference numerals.

  As shown in FIG. 1, the motor control device of this embodiment includes a high frequency current command superimposing means 11, a current control means 12, a voltage command coordinate converting means 13, a current coordinate converting means 14, and a rotor position estimating means. 15 ', an operation command means 16, a current reference signal switching means 17, an idling detection means 18, and an estimated gain switching means 19, and is applied to the inverter unit 2 that drives the permanent magnet motor 1.

  Here, the rotor position estimating means 15 'is obtained by adding an estimation completion setting means 15a and a comparator 15b to the rotor position estimating means 15 shown in FIG. In addition, the function of the estimation completion setting means 15a and the comparator 15b is achieved. That is, the DC component H, which is a value obtained by subtracting the product of the d-axis voltage high-frequency component and the d-axis current high-frequency component from the product of the q-axis voltage high-frequency component and the q-axis current high-frequency component, is set by the estimation completion setting means 15a. When the value is smaller than the value, the output HI_GAIN from the operation command means 16 is turned OFF, and the rotor position is estimated by the gain G1.

  The operation command means 16 receives the start command START at the time of start-up, the output H_LEVEL from the rotor position estimation means 15 'and the FRUN signal from the idling detection means 18, and the high frequency superposition command HF_ON for the high frequency current superposition means 11, the current reference A switching signal 0_CURR for the signal switching means 17 and a command HI_GAIN for the estimated gain switching means 19 are output.

  The current reference signal switching unit 17 is provided between the high-frequency current command superimposing unit 11 and the current control unit 12 and switches the current references IdRef2 and IdRef2 to be given to the current control unit 12 as they are or to 0.

The idling detection unit 18 includes a vector amplitude calculation unit 18a, an idling detection setting unit 18b, and a comparator 18c. The amplitude value E1_R is obtained by the following equation 1, and the amplitude value E1_R is set by the idling detection setting unit 18b. If greater than the value, the FRUN signal is output from the idling detection means 18.

  The estimated gain switching means 19 responds to the command HI_GAIN from the operation command means 16 and switches between the normal gain setting means 19a and the idling start gain setting means 19b, and the PI controller 15c of the rotor position estimating means 15 '. Are selectively given gains G1 and G2. In this case, the gain has a relationship of G1 <G2, and is set so that the rotor position estimation converges quickly during idling.

  In the motor control device according to the present embodiment configured as described above, when the start command START is input to the operation command means 16 at the time of start-up, the operation command means 16 performs a time t_OC interval as shown in FIG. The switching signal 0_CURR for the current reference signal switching means 17 is set to 1.

  As a result, the current references IdRef2 and IdRef2 output from the high-frequency current command superimposing unit 11 and applied to the current control unit 12 become zero.

  At this time, if the permanent magnet motor is in the idling state, the d-axis voltage command and the q-axis voltage commands VdRef and VqRef, which are outputs from the current control means 12, become the values of the reverse phase of the counter electromotive voltage, and the idling detection means 18 The amplitude value E1_R is obtained as in the above equation.

  In the idling detection means 18, if the amplitude value E1_R is larger than the value set by the idling detection setting means 18b, the FRUN signal is output to the operation command means 16, as shown in FIG.

  As shown in FIG. 2, after t_0C has elapsed, the operation command means 16 sets the value of H in the rotor position estimation means 15 to the high-frequency current superposition means 11 together with the high-frequency superposition command HF_ON by the estimation completion setting means 15a. The HI_GAIN signal is output to the estimated gain switching means 19 for a period longer than the value.

  Thereby, the estimated gain switching means 19 switches from the gain G1 set in the normal time gain setting means 19a to the gain G2 set in the idling start gain setting means 19b, and the PI controller of the rotor position estimating means 15 '. 15c. The rotor position estimating means 15 'performs rotor position estimation with the gain G2 set in the idling start gain setting means 19b.

  On the other hand, when the value of the DC component H in the rotor position estimating means 15 becomes smaller than the value set by the estimation completion setting means 15a, the output HI_GAIN from the operation command means 16 is turned OFF, and the rotor position estimating means 15 ' The rotor position is estimated by the gain G1 set in the normal time gain setting means 19a.

  As described above, in the motor control device of the present embodiment, only the current feedback control with the current reference being 0 is performed for a certain time from the start, and if the voltage vector amplitude during that time is equal to or greater than a certain value, the permanent magnet motor 1 Is determined to be idling, and the position estimation is performed at high speed by increasing the rotor position estimation gain when the harmonics are superimposed. Thereby, even if the permanent magnet motor 1 is rotating at high speed, it can start smoothly.

(Second Embodiment)
A motor control apparatus according to a first embodiment of the present invention will be described with reference to FIG. In FIG. 3, the same circuit elements as those in FIGS. 1 and 6 are denoted by the same reference numerals.

  As shown in FIG. 3, the motor control apparatus according to the present embodiment includes a high-frequency current command superimposing unit 11, a current control unit 12, a voltage command coordinate conversion unit 13, a current coordinate conversion unit 14, and a rotor position estimation unit. 15, operation command means 16, current reference signal switching means 17, idling detection means 18, and estimated gain switching means 19 ′, and is applied to the inverter unit 2 that drives the permanent magnet motor 1.

  The estimated gain switching means 19 'has a t_hg one-shot circuit 19c so that the output HI_GAIN from the operation command means 16 is turned ON after t_hg has elapsed, and after this t_hg has elapsed, the normal gain setting means 19a is provided. And the idling start gain setting means 19b are switched to selectively give gains G1 and G2 to the PI controller 15c of the rotor position estimating means 15 '. The gain has a relationship of G1 <G2, and is set so that the rotor position estimation converges quickly during idling.

  In the motor control device of the present embodiment configured as described above, when the start command START is input to the operation command means 16 at the time of start-up, the operation command means 16 is set to the current reference signal switching means 17 for the time t_OC. The switching signal 0_CURR for is set to 1.

  As a result, the current references IdRef2 and IdRef2 output from the high-frequency current command superimposing unit 11 and applied to the current control unit 12 become zero.

  At this time, if the motor 1 is in the idling state, the d-axis voltage command and the q-axis voltage commands VdRef and VqRef, which are outputs from the current control means 12, become values of opposite phases of the counter electromotive voltage, and the idling detection means 18 The amplitude value E1_R is obtained as in Equation 1 above.

  If the amplitude value E1_R is larger than the value set by the idling detection setting means 18b, the FRUN signal is output from the idling detection means 18, and after the elapse of t_0C from the operation command means 16, the high frequency current superposition means 11 is instructed. Along with HF_ON, the rotor position estimating means 15 outputs a HI_GAIN signal to the estimated gain switching means 19 for a preset t_hg time.

  Thereby, the estimated gain switching means 19 ′ is used for estimating the rotor position by switching from the gain G1 set in the normal time gain setting means 19a to the gain G2 set in the idling start gain setting means 19b.

  After t_hg elapses after the output HI_GAIN from the operation command means 16 is turned on, it is turned off and the rotor position is estimated by the gain G1.

  As described above, in the motor control device of the present embodiment, only the current feedback control with the current reference being 0 is performed for a certain time from the start, and if the voltage vector amplitude during that time is equal to or greater than a certain value, the permanent magnet motor 1 Is determined to be idling, and the position estimation is performed at high speed by increasing the rotor position estimation gain when the harmonics are superimposed. Thereby, even if the permanent magnet motor 1 is rotating at high speed, it can start smoothly.

  Further, after the estimated gain is increased by the t_hg one-shot circuit 19c of the estimated gain switching means 19 'to speed up the estimated response, the estimated gain can be returned to the normal state.

(Third embodiment)
A motor control apparatus according to a third embodiment of the present invention will be described with reference to FIG. In FIG. 3, the same circuit elements as those in FIGS. 1, 3 and 6 are denoted by the same reference numerals.

  As shown in FIG. 4, the motor control apparatus of this embodiment includes a high frequency current command superimposing means 11, a current control means 12, a voltage command coordinate converting means 13, a current coordinate converting means 14, and a rotor position estimating means. 15 ′, operation command means 16, current reference signal switching means 17, idling detection means 18, and high-frequency current command switching means 20, and is applied to the inverter unit 2 that drives the permanent magnet motor 1.

  The high-frequency current command switching means 20 responds to the HF_SEL signal input during a period when the value of the DC component H is larger than the value set by the estimation completion setting means 15a in the rotor position estimating means 15 ′, The high frequency current applied by the superimposing means 11 is switched from the high frequency current command HF1 set in the setting means 20a to the high frequency current command HF2 set in the idling start time setting means 20b. In this case, the high-frequency current command is set so that the rotor position estimation converges quickly in the rotor position estimating means 15 'when starting from idling due to the relationship of HF1 <HF2.

  In the motor control device of the present embodiment configured as described above, when the start command START is input to the operation command means 16 at the time of start-up, the operation command means 16 is set to the current reference signal switching means 17 for the time t_OC. The switching signal 0_CURR for is set to 1.

  As a result, the current references IdRef2 and IdRef2 output from the high-frequency current command superimposing unit 11 and applied to the current control unit 12 become zero.

  At this time, if the permanent magnet motor is in the idling state, the d-axis voltage command and the q-axis voltage commands VdRef and VqRef, which are outputs from the current control means 12, become the values of the reverse phase of the counter electromotive voltage, and the idling detection means 18 The amplitude value E1_R is obtained as shown in Equation 1 above.

  If the amplitude value E1_R is greater than the value set by the idling detection setting means 18b, the FRUN signal is output from the idling detection means 18, and after the elapse of t_0C from the operation command means 16, the high frequency superposition command HF_ON At the same time, the HF_SEL signal is output to the harmonic current command switching means 20 during a period when the value of the DC component H is larger than the value set by the estimation completion setting means 15a in the rotor position estimation means 15 '.

  The harmonic current command switching means 20 responds to the HF_SEL signal, and sets the high frequency current applied by the high frequency current superimposing means 11 at the normal time from the high frequency current command HF1 set in the setting means 20a to the idling start time setting means 20b. The high-frequency current command HF2 is switched to.

  When the value of the DC component H in the rotor position estimating means 15 'becomes smaller than the value set by the estimation completion setting means 15a, the output HF_SEL from the operation command means 16 is turned OFF and is applied by the high frequency current superimposing means 11 in normal times. The normal high frequency current command in which the set high frequency current is set in the setting means 20a is applied.

  As described above, in the motor control device of the present embodiment, only the current feedback control with the current reference set to 0 is performed for a certain time from the start, and if the voltage vector amplitude during that time is equal to or greater than a certain value, the permanent magnet motor 1 The position is estimated at high speed by determining that the vehicle is idling and increasing the high-frequency current command when the harmonics are superimposed.

  Thereby, even if the permanent magnet motor 1 is rotating at high speed, it can be started smoothly, and vibration and noise due to high frequency can be minimized by using the minimum high frequency current command in normal times.

(Fourth embodiment)
A motor control apparatus according to a fourth embodiment of the present invention will be described with reference to FIG. In FIG. 3, the same circuit elements as those in FIGS. 1, 3, 4 and 6 are denoted by the same reference numerals.

  As shown in FIG. 5, the motor control device of this embodiment includes a high-frequency current command superimposing means 11, a current control means 12, a voltage command coordinate conversion means 13, a current coordinate conversion means 14, and a rotor position estimation means. 15, operation command means 16, current reference signal switching means 17, idling detection means 18, and high-frequency current command switching means 20 ′, and is applied to the inverter unit 2 that drives the permanent magnet motor 1.

  The high-frequency current command switching means 20 'outputs a high-frequency superposition command HF_ON from the operation command means 16 to the high-frequency current superposition means 11, and also outputs an HF_SEL signal to the harmonic current command switching means 20' and a t_hg one-shot circuit 20c. The high frequency current command set in the idling start time setting means 20b from the high frequency current command HF1 set in the setting means 20a to the high frequency current applied by the high frequency current superimposing means 11 at the normal time when output for t_hg time set in advance by It switches to HF2. In this case, the high-frequency current command is set so that the rotor position estimation means converges quickly in the rotor position estimating means 15 when starting from idling because of the relationship of HF1 <HF2.

  In the motor control device of the present embodiment configured as described above, when the start command START is input to the operation command means 16 at the time of start-up, the operation command means 16 is set to the current reference signal switching means 17 for the time t_OC. The switching signal 0_CURR for is set to 1.

  As a result, the current references IdRef2 and IdRef2 output from the high-frequency current command superimposing unit 11 and applied to the current control unit 12 become zero.

  At this time, if the permanent magnet motor is in the idling state, the d-axis voltage command and the q-axis voltage commands VdRef and VqRef, which are outputs from the current control means 12, become the values of the reverse phase of the counter electromotive voltage, and the idling detection means 18 The amplitude value E1_R is obtained as shown in Equation 1 above.

  If the amplitude value E1_R is larger than the value set by the idling detection setting means 18b, the FRUN signal is output from the idling detection means 18, and after the elapse of t_0C from the operation command means 16, the high frequency current superposition means 11 is instructed. Together with HF_ON, the rotor position estimating means 15 outputs the HF_SEL signal to the harmonic current command switching means 20 for a preset t_hg time.

  As a result, the harmonic current command switching means 20 'causes the high-frequency current applied by the high-frequency current superimposing means 11 at the normal time from the high-frequency current command HF1 set in the setting means 20a to the high frequency set in the idling start setting means 20b. Switch to current command HF2.

  After t_hg has elapsed since the output HF_SEL from the operation command means 16 is turned ON, it is turned OFF, and the normal high frequency current command in which the high frequency current applied by the high frequency current superimposing means 11 is set in the setting means 20a is applied. The

  As described above, in the motor control device of the present embodiment, only the current feedback control with the current reference set to 0 is performed for a certain time from the start, and if the voltage vector amplitude during that time is equal to or greater than a certain value, the permanent magnet motor 1 The position is estimated at high speed by determining that the vehicle is idling and increasing the high-frequency current command when the harmonics are superimposed.

  Thereby, even if the permanent magnet motor 1 is rotating at high speed, it can be started smoothly, and vibration and noise due to high frequency can be minimized by using the minimum high frequency current command in normal times.

  Further, after the high frequency current command is increased by the action of the t_hg one-shot circuit 20c of the high frequency current command switching means 20 'to speed up the estimated response, the high frequency current command value can be returned to the normal state.

  Note that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention at the stage of implementation. In addition, the embodiments may be appropriately combined as much as possible, and in that case, combined effects can be obtained. Furthermore, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, when an invention is extracted by omitting some constituent elements from all the constituent elements shown in the embodiment, when the extracted invention is implemented, the omitted part is appropriately supplemented by a well-known common technique. It is what is said.

The block diagram which shows 1st Embodiment of the motor control apparatus by this invention. The sequence diagram in 1st Embodiment of the motor control apparatus by this invention. The block diagram which shows 2nd Embodiment of the motor control apparatus by this invention. The block diagram which shows 3rd Embodiment of the motor control apparatus by this invention. The block diagram which shows 4th Embodiment of the motor control apparatus by this invention. The block diagram which shows an example of the conventional motor control apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Permanent magnet motor, 2 ... Inverter, 11 ... High frequency current command superimposing means, 12 ... Current control means, 13 ... Voltage command coordinate conversion means, 14 ... Current coordinate conversion means, 15 ... Rotor position estimation means, 15a ... Estimation Completion setting means, 16 ... operation command means, 17 ... current reference signal switching means, 18 ... idling detection means, 18a ... vector amplitude calculation unit, 18b ... idling detection setting means, 18c ... comparator, 19 ... estimated gain switching means, 19a: Normal gain setting means, 19b: idling gain setting means, 20 ... high frequency current command switching means, 20a ... normal high frequency current setting means, 20b ... idling high frequency current setting means.

Claims (4)

In a motor control device applied to a permanent magnet motor having a magnetic saliency on a motor rotor and supplied with an output from an inverter that converts DC power into AC power,
A rotational current command having a high frequency component different from the rotational frequency of the motor rotor, a d-axis current command related to the rotor projecting direction necessary for outputting torque, and a q-axis current command related to a direction perpendicular to the rotor projecting direction High frequency current command superimposing means for superimposing each on
The d-axis voltage command and q-axis voltage command of the inverter output are operated so that the actual values of the d-axis current and q-axis current of the motor follow the current command value output from the high-frequency current command superimposing means. Current control means;
Using the actual values of the d-axis voltage command, the q-axis voltage command, the d-axis current, and the q-axis current, the frequency component of the high-frequency current superimposed by the high-frequency current command superimposing means for each input value is extracted, and A value obtained by subtracting the product of the d-axis voltage high-frequency component and the d-axis current high-frequency component from the product of the q-axis voltage high-frequency component and the q-axis current high-frequency component is calculated, and the direct current component of the calculated value is zero. A rotor position estimating means for correcting and outputting the estimated rotational speed value of the rotor, and outputting a time integral value of the estimated rotational speed value of the motor rotor as the estimated position value of the motor rotor;
Voltage command coordinate conversion for converting a d-axis voltage command and a q-axis voltage command, which are outputs from the current control unit, into a three-phase voltage command using the estimated position value of the motor rotor by the rotor position estimation unit Means,
Current coordinate conversion means for converting the three-phase current of the motor into the d-axis current and the q-axis current, which are values on the dq-axis coordinate axes, using the estimated position of the motor rotor;
Immediately after start-up, current feedback control is performed so that the current flowing into the motor becomes a desired value including zero. When the output voltage command at this time exceeds a predetermined amount, the motor is rotating. An idling determination means for determining that there is,
If the idling determination means determines that the motor is rotating immediately after start-up, the d-axis voltage high-frequency component is calculated from the product of the q-axis voltage high-frequency component and the q-axis current high-frequency component calculated by the rotor position estimation means. Until the DC component of the value obtained by subtracting the product of the high-frequency component and the d-axis current converges within a predetermined range, the estimated gain of the rotor position estimating means is increased to speed up the estimation response, and the DC component is within the predetermined range. And a control means for returning the estimated gain to the normal state after the convergence to the motor control device. When the control means determines that the motor is rotating immediately after the start of the start, the control means increases the estimated gain of the rotor position estimating means for a certain period of time to accelerate the estimated response, and then estimates 2. The motor control device according to claim 1, further comprising means for returning the gain to a normal state. If the control means determines that the motor is rotating immediately after starting, the control means calculates the product of the q-axis voltage high-frequency component and the q-axis current high-frequency component calculated by the rotor position estimating means. The high-frequency current command superimposed by the high-frequency current command superimposing means is increased until the DC component of the value obtained by subtracting the product of the d-axis voltage high-frequency component and the d-axis current high-frequency component converges within a predetermined range. 2. The motor control device according to claim 1, further comprising means for returning the high-frequency current command to a normal state after the DC component converges within a predetermined range. When the control means determines that the motor is rotating immediately after start-up, the control means increases the high-frequency current command superimposed by the high-frequency current command superimposing means for a certain period of time to speed up the estimated response. 2. The motor control device according to claim 1, further comprising means for returning the high-frequency current command value to a normal state.

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