WO2017081977A1 - Motor control device and elevator in which same is used - Google Patents

Abstract

The invention is equipped with a control unit (150) that, according to switching criteria calculated from the magnetic characteristics of an AC motor (9), executes an operating sequence for selecting one of three control modes: an online control mode in which torque ripple suppression is performed using a torque ripple suppression unit (80), a learning control mode in which, at the same time torque ripple suppression is performed using the torque ripple suppression unit (80), suppression control parameters are stored in a suppression control parameter storage unit (120), and an offline control mode in which torque ripple suppression is performed using the suppression control parameters stored in the suppression control parameter storage unit (120).

Description

Motor control device and elevator using the same

The present invention relates to a motor control device such as a three-phase AC motor and an elevator using the same.

AC motors, in particular PM motors (Permanent Magnet Synchronous Motors), are characterized by their small size and high efficiency, and in recent years have been widely used for industrial equipment.

However, since the PM motor includes a harmonic component in the induced voltage due to its structure, an order component that is an integral multiple (mainly 6 times) the motor electrical angle with respect to the generated torque (hereinafter, this order component is referred to as a 6f component). ) With torque ripple that is a disturbance that vibrates. Since this torque ripple can cause problems such as vibration, noise, mechanical resonance, etc., its reduction technology (hereinafter referred to as torque ripple suppression control) is required.

In order to perform torque ripple suppression control, it is necessary to acquire information corresponding to the target torque ripple. For this purpose, a feed-forward method (hereinafter referred to as FF method) in which information is obtained by performing tests and analyzes in advance and stored in the control device, and a feedback method (hereinafter referred to as FF method) that is acquired online during motor driving ( Hereinafter, it is broadly classified as “FB method”.

While the former FF method has the advantage of being able to suppress torque ripple with high response, it requires complicated pre-acquisition work of torque ripple information, and torque ripple information acquired in advance due to aging of motors and devices is appropriate. There is a disadvantage that it disappears.
The latter FB method does not require complicated acquisition of torque ripple information in advance, and has the advantage of being able to perform appropriate torque ripple suppression control in response to aging of motors and devices, but the torque ripple suppression response is torque ripple. There are disadvantages that it cannot be higher than the frequency and that there are high technical barriers to acquiring information equivalent to torque ripple online.

Therefore, a learning control method combining these two methods has been proposed (see, for example, Patent Document 1 below). That is, when driving as the FB system online, the torque ripple suppression command value is stored, and when high response is required, the stored command command value is used to operate in the FF system. In other words, there is a method of driving the FF system basically, and updating the suppression command value by the FB system during steady operation.

Japanese Patent No. 5434369

Thus, in the learning method, torque ripple suppression control can be performed by combining the advantages of both by appropriately switching between the FF method and the FB method. However, when the switching timing is not appropriate, an incorrect suppression command value is learned. Therefore, it is important to set an operation sequence for managing the switching timing. In particular, there is a problem particularly when torque ripple transfer characteristics cannot be accurately grasped, such as when estimating torque ripple based on motor parameters from electrical information to simplify the system.

For torque ripple suppression control, it is necessary to estimate the information of the 6f component online, but this is very difficult in the RL circuit model on the commonly used rotational coordinates (dq coordinates). Exists.

FIG. 15 is an example showing a change in the q-axis magnetic flux φ _q when the q-axis current i _q is increased in a state where the PM motor is controlled at a constant speed. The slope in this figure is the q-axis inductance, but the following two points are problematic here.

(I) Changes in the fundamental wave component of the inductance, that is, the inductance changes according to the current due to the magnetic saturation of the motor.
(Ii) A change in the harmonic component of the inductance, that is, the inductance forms a hysteresis minor loop.
Here, the hysteresis minor loop, the enlarged view of FIG. 15, since the q-axis magnetic flux phi _q can take multiple values even for the same q-axis current i _q, the q-axis magnetic flux phi _q is a small loop It is to change as it forms.

With regard to (i) above, the inductance is saturated and becomes smaller as the current increases, so that the torque transfer characteristics may differ due to an error between the motor circuit model recognized by the controller and that of the actual motor. It becomes a problem.

As for (ii) above, since the inductance value differs depending on the rotor position even with the same current, a hysteresis minor loop is formed since it has a harmonic component corresponding to the motor electrical angle, similar to the torque ripple. To do. If it has such characteristics, even if it is set so that the inductance changes according to the current in consideration of the magnetic saturation characteristics, the inductance seen on the coordinates of the harmonics changes according to the rotor position. become. That is, even if the torque transmission characteristics are matched, the torque ripple transmission characteristics are different, so that it is difficult to obtain accurate torque ripple information.

The present invention has been made to solve the above-described problems, and when performing torque ripple suppression control in accordance with changes in the speed and magnetic characteristics of the motor, the operation sequence is appropriately managed to achieve high accuracy. An object of the present invention is to provide a motor control device capable of torque ripple suppression control and an elevator using the same.

A motor control device according to the present invention includes an AC motor, a current detection unit that detects a current of at least two phases of three phases, and a current control unit that generates a voltage command value in a control coordinate axis using the detected current value A torque estimation unit that estimates the torque of the AC motor based on the voltage command value and the current detection value, a torque ripple suppression unit that generates a suppression command that suppresses torque ripple of the AC motor based on the estimated torque, and the suppression command And a suppression control parameter storage unit that stores the suppression control parameter for generating the motor in association with the speed and current command value of the AC motor, and according to the switching condition calculated from the magnetic characteristics of the AC motor, Online control mode in which torque ripple suppression is performed by the torque ripple suppression unit, and torque ripple by the torque ripple suppression unit. The control mode includes a learning control mode in which the suppression control parameter is stored in the suppression control parameter storage unit and an offline control mode in which torque ripple suppression is performed by the suppression control parameter stored in the suppression control parameter storage unit. A control unit that executes an operation sequence for selecting one of the above.
The elevator according to the present invention includes the motor control device having the above-described configuration, a car, a counterweight, a rope that connects the car and the counterweight, and the rope that rotates by the driving force of the AC motor. And a drive sheave on which is wound.

The motor control device according to the present invention and an elevator using the motor control device have one of three control modes, an online control mode, a learning control mode, and an offline control mode, according to the switching condition based on the magnetic characteristics of the AC motor. Since the operation sequence to be selected is executed, it becomes possible to learn appropriate suppression control parameters and to effectively suppress torque ripple.

It is a block diagram which shows the structure of the motor control apparatus which concerns on Embodiment 1 of this invention. It is a block diagram which shows an example of a structure of the torque ripple compensation instruction | command production | generation part of the motor control apparatus of Embodiment 1 of this invention. It is a block diagram which shows operation | movement of the online control mode of the motor control apparatus of Embodiment 1 of this invention. It is a block diagram which shows operation | movement of the learning control mode of the motor control apparatus of Embodiment 1 of this invention. It is a block diagram which shows operation | movement of the offline control mode of the motor control apparatus of Embodiment 1 of this invention. It is a flowchart which shows the switching operation sequence of the control mode in the motor control apparatus of Embodiment 1 of this invention. It is a graph which shows typically the switching operation sequence of the control mode in the motor control device of Embodiment 1 of this invention. It is a graph which shows typically the other switching operation sequence of the control mode in the motor control apparatus of Embodiment 1 of this invention. It is a graph which shows typically the other switching operation sequence of the control mode in the motor control apparatus of Embodiment 1 of this invention. It is a block diagram which shows the structure of the motor control apparatus which concerns on Embodiment 2 of this invention. It is a block diagram which shows operation | movement of the on-line control mode of the motor control apparatus of Embodiment 2 of this invention. It is a block diagram which shows operation | movement of the learning control mode of the motor control apparatus of Embodiment 2 of this invention. It is a block diagram which shows operation | movement of the offline control mode of Embodiment 2 motor control apparatus of this invention. It is a flowchart which shows the switching operation sequence of the control mode in the motor control apparatus of Embodiment 4 of this invention. It is a characteristic view which shows an example of the magnetic saturation characteristic of an AC motor. It is a schematic block diagram in Embodiment 5 which applied the motor control apparatus in this invention to the elevator. It is a flowchart which shows the switching operation sequence of the control mode in the motor control apparatus with which the elevator of Embodiment 5 of this invention is provided.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a configuration of a motor control device according to Embodiment 1 of the present invention.

The motor control device according to the first embodiment controls a PM motor (hereinafter simply referred to as a motor) 9 that is an AC motor via a power converter 3. The motor control device includes a current command generation unit 10 that outputs current command values i ^* _d and i ^* _q based on a torque command value τ ^* , and an output of the current command generation unit 10 that outputs a current from the three-phase-dq converter 5. Subtractors 6 and 7 for subtracting the output, current control unit 1 for generating voltage command values v ^* _d and v ^* _q on the control coordinate axes using the outputs of these subtractors 6 and 7, and the voltage from this current control unit 1 Dq-three-phase converter 2 that generates a three-phase AC voltage based on the command values v ^* _d and v ^* _q, and electric power that controls the power supplied to the motor 9 based on the output of the dq-three-phase converter 2 Converter 3, current detector 4 that detects at least two of the three-phase currents supplied to motor 9, rotational position detector 8 such as an encoder that detects the rotational position of motor 9, and current detector 4 The detected current obtained in step d is the d-axis current of the control coordinate axis. comprising a three-phase -dq converter 5 which converts the _d and q-axis current _{i q.}

Furthermore, the motor control device of the first embodiment associates the torque ripple suppression unit 80 that generates a suppression command for torque ripple suppression of the motor 9 and the suppression control parameter for torque ripple suppression with the speed of the motor 9 and the current command value. And a control unit 150 such as a microcomputer for controlling the suppression control parameter storage unit 120.

The torque ripple suppression unit 80 includes a torque estimation unit 90 that calculates the estimated torque value τ of the motor 9 based on the voltage command value v ^* _dq , the detected current value i ^* _dq , and the rotational position θ _re of the motor 9, and the motor 9 Torque ripple compensation signal for generating a torque ripple compensation signal τ ^* _rip as a suppression command for suppressing torque ripple of the motor 9 based on the rotational position θ _{re of} the motor and the estimated torque value τ from the torque estimating unit 90 and outputting it to the current command generating unit 10 The command generation unit 100 is included.

The control unit 150 controls the operation of the torque ripple suppression unit 80 and the suppression control parameter storage unit 120, and based on the speed of the motor 9 and the magnetic characteristics of the motor 9 (inductance characteristics shown in FIG. 15 above). Online suppression control mode in which torque ripple suppression is performed by the torque ripple suppression unit 80 and torque ripple suppression is performed by the torque ripple suppression unit 80 in accordance with the switching conditions (ω _{re_low} , ω _{re_high} , i _{q_mg} , i _{q_hys} ) described later. At the same time, one of the three control modes of the learning control mode in which the suppression control parameter is stored in the suppression control parameter storage unit 120 and the offline control mode in which torque ripple suppression is performed using the suppression control parameter stored in the suppression control parameter storage unit 120. To select one It is to run the Sequence.

FIG. 2 is a block diagram showing an example of the configuration of the torque ripple compensation command generation unit 100 described above. The configuration and operation of each part shown in FIGS. 1 and 2 are further clarified by the following description of the operation.

Next, in the motor control device having the above-described configuration, the operation of the online control mode for estimating the power of the motor 9 from the voltage and current supplied to the motor 9 and suppressing the torque ripple based on the estimated power will be described with reference to FIG. Will be described.

The torque estimation unit 90 includes a motor constant, an actual current vector i _dq composed of dq axis actual currents i _q and i _d , and a voltage vector v ^* _dq composed of voltage command values v ^* _d and v ^* _q to the motor 9. Based on the electrical angle θ _re of the motor detected by the rotational position detector 8, an estimated voltage estimated value vector _edq as an estimated induced voltage of the motor 9 is estimated by the calculation of the following equation (1).

Here, R represents the winding resistance of the motor, L is the self-inductance, P _m is the number of pole pairs, s is a differential operator, omega _rm is mechanical angular, the omega _re represents the speed of the motor 9 (electrical angular velocity).

Further, the torque estimation unit 90 estimates the torque of the motor 9 by the following formula (2) based on the induced voltage estimated value vector _edq and the actual current vector i _dq obtained by the formula (1), The estimated torque value τ is output to the torque ripple compensation command generation unit 100.

The torque ripple compensation command generation unit 100 generates a torque ripple compensation signal τ ^* _rip that extracts the vibration component included in the estimated torque value τ and cancels the vibration, and uses the torque ripple compensation signal τ ^* _rip as the current command generation unit 10. Output to. There are a number of known techniques for generating the torque ripple compensation signal τ ^* _rip based on the estimated torque value τ. Here, as an example, the torque ripple compensation command generation unit 100 having the configuration shown in FIG. 2 is adopted. Yes.

In FIG. 2, first, a pulsation component included in the estimated torque value τ is extracted by the extraction unit 101 a constituting the processing unit 101. As the calculation method, any known technique can be used. For example, the calculation of the following equation (3) with reference to Fourier series expansion can be used for the estimated torque value τ.

Where τ _Cn is the cosine coefficient of the estimated torque value τ, τ _Sn is the sine coefficient of the estimated torque value τ, F _LPF (s) is the gain of the low-pass filter, n is the torque ripple order, and Δθ _est is the actual value of the estimated torque value τ. This is a phase compensation setting value for compensating for the estimated delay from the torque, and is set in the phase compensation unit 101 b constituting the processing unit 101. In this case, the compensation set value Δθ _est is obtained in advance from actual measurements or models.

Next, the cosine coefficient τ _Cn and the sine coefficient τ _Sn obtained by the processing unit 101 are input to the subtracters 102a and 103a, respectively. The subtractors 102a and 103a and the suppression control units 102b and 103b calculate a torque ripple amplitude suppression value by calculating the following equation (4), and calculate a torque ripple compensation cosine coefficient τ ^* _Cn and a torque ripple compensation sine coefficient τ ^* _Sn . And output to the multipliers 105b and 106b, respectively.

Here, G _rip (s) represents transfer characteristics of the suppression control units 102b and 103b, and τ ^** _Cn and τ ^** _Sn represent torque ripple suppression command values.

The multipliers 105b and 106b and the adder 107 perform the calculation of the following equation (5) to convert them into a periodic signal as a conversion signal synchronized with the torque ripple period, and output a torque ripple compensation signal τ ^* _rip. The compensation signal τ ^* _rip is input to the current command generator 10 to suppress torque ripple.

The periodic signal generators 105a and 106a are based on an electrical angular velocity (hereinafter simply referred to as speed) ω _re obtained by differentiating the electrical angle θ _re of the motor 9 obtained by the rotational position detector 8 by the differentiator 108. A periodic signal that has undergone phase compensation is generated based on the phase compensation setting value Δθ _i corresponding to the control delay of the current control system.

However, Δθ _i represents a set value of phase compensation based on the control delay of the control system. In this case, the phase compensation set value Δθ _i is obtained from actual measurements or models and set in advance.

Next, the operation in the learning control mode shown in FIG. 4 will be described.
In this learning control mode, in parallel to the operation in the online control mode, in addition to this, the suppression control parameter storage unit 120 is in an operating state, and the suppression control unit 102b constituting the torque ripple compensation command generation unit 100, torque ripple compensation cosine coefficient tau ^* _Cn outputted from the 103b, and the torque ripple compensation sine coefficient tau ^* _Sn, as suppression control parameters for generating a torque ripple compensation signal tau ^* _rip, velocity omega _re and the q-axis current command of the motor 9 _Stored in association with the value i ^* _q .

Next, the operation in the offline control mode shown in FIG. 5 will be described.
In the offline control mode, the torque estimation unit 90 is in a stopped state. For this reason, the control operation of the suppression control units 102b and 103b of the torque ripple compensation command generation unit 100 is also stopped. Therefore, in this case, the control unit 150 controls the suppression control parameters τ ^* _Cn and τ ^* corresponding to the speed _ωre and the q-axis current command value i ^* _q of the motor 9 stored in the suppression control parameter storage unit 120 ^. _Sn is read and output to the multipliers 105b and 106b. Thereby, the calculation based on the above-described equations (4) and (5) is performed, and the torque ripple compensation signal τ ^* _rip is generated off-line from the torque ripple compensation command generation unit 100, and this torque ripple compensation signal τ ^* _rip is converted into the current command. The torque ripple is suppressed by being input to the generation unit 10.

Next, a sequence operation for switching the above three control modes to each other will be described. To do this, represents: (a) a switching condition for setting the appropriate control mode for speed omega _re of the motor 9, (b) the magnetic characteristics of the motor 9 (inductance characteristics shown above in FIG. 15) It is divided into switching conditions for setting an appropriate control mode for the q-axis current command value i ^* _q .
First, a description will be given switching condition for setting the appropriate control mode for speed omega _re of the motor 9 in the (a).

At the first start-up, the torque ripple frequency is low and the online control response cannot be increased, so the start-up is performed in the off-line control mode. Then, the speed omega _re of the motor 9 until the predetermined first speed threshold omega _{Re_low} than a preset continues the offline control mode as the activation period.

Here, as an example of the setting of the first velocity threshold omega _{Re_low} above, torque ripple will be described when it is desired to operate in the offline control mode until more frequency velocity response omega _sc. Since the torque ripple as previously described is a vibration generated in order component of an integral multiple of motor electrical angle, the frequency is nω _re. Therefore, the speed condition in which the torque ripple frequency is equal to or higher than the speed response ω _sc is ω _sc <nω _re ⇔ω _re > ω _sc / n. That is, if ω _{re — low} > ω _sc / n [rad / sec] is set, the operation in the offline control mode can be continued until the torque ripple becomes a frequency equal to or higher than the speed response.

Since the velocity omega _re of the motor 9 is also equal to or more than the first speed threshold omega _{Re_low,} during acceleration and deceleration reduction control parameter τ ^* _Cn, τ ^* _Sn keep changing, suppressing control parameter τ ^* _Cn, τ ^* _Sn The learning process is not performed, and the online control mode is entered.

Once in steady operation deceleration is completed, proceeds suppressing control parameter from the online control mode to the learning control mode τ ^* _Cn, τ ^* _Sn and speed of the motor 9 omega _re and q-axis current command value i ^* _q And stored in the suppression control parameter storage unit 120.

Further, in this steady operation, when the speed omega _re of the motor 9 is at too high speed, there is a case where the torque ripple is high frequency such as exceed the bandwidth of the control system. In such a case, it is difficult to appropriately suppress the torque ripple, and the suppression control parameters τ ^* _Cn and τ ^* _Sn obtained at that time are not appropriate. Therefore, set in advance predetermined second speed threshold _ω re_high (> ω re_low), when the speed omega _re of the motor 9 was a second speed threshold omega _{Re_high} above, online control mode or learning Shift to the offline control mode without shifting to the control mode.

Here, an example of setting the second speed threshold value _{ωre_high} will be described. In this embodiment, when the q-axis current command value i ^* _q is corrected and torque ripple is suppressed via the current control unit 1, the frequency of the correction signal is equal to or higher than the current control response ω _cc in the current control unit 1. The effect is attenuated. That is, on-line control functions accurately if the relationship of ω _cc > nω _re ⇔ω _re <ω _cc / n holds between the torque ripple frequency nω _re and the current control response ω _cc . Accordingly, by _setting ω _{re_high} <ω _cc / n [rad / sec], an appropriate online control mode or learning control mode can be operated.

Next, switching conditions for setting an appropriate control mode for the magnetic characteristics of the motor 9 in (b) will be described by taking as an example the case where the motor 9 has an inductance characteristic as shown in FIG.

From the inductance characteristics of the motor 9 as shown in FIG. 15, the switching threshold value for each control mode is set in advance for the q-axis current command value i ^* _q . First, when the rating is 100% or less, the learning control mode is set in the steady state. Next, since the magnetic saturation starts from the point where the rating exceeds 100% and the inductance becomes small, appropriate suppression control parameters τ ^* _Cn and τ ^* _Sn are obtained even in a steady state in the region where the magnetic saturation starts. Therefore, the learning control mode is not shifted to, but only the online control mode is operated. The condition of the q-axis current command value i ^* _q at which this magnetic saturation starts is set as the first current threshold i _{q_mg} .

Furthermore, since an inductance hysteresis minor loop appears from around the rated value of 200%, appropriate suppression control parameters τ ^* _Cn and τ ^* _Sn cannot be obtained. For example, when the q-axis current command value i ^* _q is a value corresponding to a load of 150% or more, a margin is provided so that the offline control mode is always operated. The condition of the q-axis current command value i ^* _q in which this hysteresis minor loop appears is set as a second current threshold value i _{q_hys} (> i _{q_mg} ).

As described above, in the first embodiment, the control unit 150 matches the conditions of both the speed _ωre of the motor 9 and the magnetic characteristics (particularly, the inductance characteristics in this case) of the motor 9, and the online control mode and the learning control mode. Then, an operation sequence for selecting one of the three control modes of the offline control mode is executed.

The operation sequence when the control unit 150 selects and switches between the three control modes in this case is shown in the flowchart of FIG. Reference sign S means a processing step.
That is, step S101 is performed after starting, and operation | movement is started as an offline control mode. During operation of the offline control mode determination of the switching condition regarding speed omega _re of the motor 9 in Step S102 it is performed. That is, it is determined whether the speed omega _re of the motor 9 is first velocity threshold omega _{Re_low} more.
In step S103, the switching condition relating to the inductance characteristic (q-axis current command value i ^* _q ) is determined. That is, it is determined whether the q-axis current command value i ^* _q is equal to or less than the second current threshold value i _{q_hys} .
If at least one of step S102 and step S103 is negative, the offline control mode is continued. On the other hand, step S104 is executed only when step S102 and step S103 are both true, and the process shifts to the online control mode.

During the operation in the online control mode, the switching condition relating to the inductance characteristic (q-axis current command value i ^* _q ) is determined in step S105. That is, it is determined whether the q-axis current command value i ^* _q is equal to or less than the first current threshold value i _{q_mg} .
Moreover, the determination of the switching condition on the velocity omega _re carried out in step S106, S107. That is, in step S106, it is determined whether the motor is in a steady state without acceleration / deceleration. Speed omega _re step S107 the motor 9 is determined or less than a second speed threshold _ω re_high.
If at least one of step S105 and step S106 is negative, a determination is further made in step S102 and step S103 to determine whether to continue the online control mode.
If both steps S105 and S106 are true, a determination is made in step S107. If not in this case, step S101 is executed to shift to the offline control mode. If true in step S107, step S108 is executed to shift to the learning control mode.

During the operation in the learning control mode, the determinations in steps S105, S106, and S107 are performed, and it is determined whether to continue the learning control mode or to shift to the offline control mode or the online control mode.

FIG. 7 is a graph schematically showing the switching of the control mode.
In FIG. 7, the horizontal axis represents the first speed threshold value ω _{re_low} and the second speed threshold value ω _{re_high} , and the vertical axis represents the first current threshold value i _{q_mg} and the second current threshold value i _{q_hys.} Each is divided into nine regions (I) to (IX). In this case, the offline control mode is selected in all of the regions (I) to (III), (VI), and (VII) to (IX). In the region (IV), the online control mode is learned when not in the steady state, and the learning is performed in the steady state. The control mode is selected, and the online control mode is selected in the region (V).

As described above, in the first embodiment, the online control mode, the learning control mode, and the offline control mode are matched to the conditions of both the speed _ωre of the motor 9 and the magnetic characteristics (particularly, the inductance characteristics in this case) of the motor 9. Since an operation sequence for selecting one of the three control modes is provided, it is possible to learn an appropriate suppression control parameter and to effectively suppress torque ripple.

It should be noted that the present invention is not limited to the case where each control mode is assigned to each of the regions (I) to (IX) shown in FIG. 7, but the q-axis current command value i ^* _q is set to i _{q_mg} <i as shown in FIG. ^{In *} _q <i _{q_hys} (region (V) in FIG. 8), the learning control mode may be selected instead of the online control mode. Further, the q-axis current command value i ^* _q is i _q > i _{q_hys} (in the region (VI) in FIG. 8, the learning control mode cannot be performed, but the online control mode may be selected instead of the offline control mode). .

In the first embodiment, the online control mode, the learning control mode, and the offline control are performed in accordance with both conditions of the speed _ωre of the motor 9 and the q-axis current command value i ^* _q that is the magnetic characteristic of the motor 9. Although the three control modes are selected and switched, the present invention is not limited to this, and as shown in FIG. 9, one of the three control modes is selected according to only the condition of the q-axis current command value i ^* _q. May be selected.

That is, in FIG. 9, when the q-axis current command value i ^* _q is _greater than or _equal to the second current threshold value i _{q_hys} (in the case of regions (III), (VI), and (IX)), the offline control mode is all selected. The learning control mode is selected in all cases where the current threshold value is less than or equal to the second current threshold value i _{q_hys} (in the case of the regions (I), (II), (IV), (V), (VII), (VIII)).

Embodiment 2. FIG.
FIG. 10 is a block diagram showing the configuration of the motor control apparatus according to Embodiment 2 of the present invention. In the second embodiment, FIG. 11 is a block diagram during operation in the online control mode, FIG. 12 is a block diagram during operation in the learning control mode, and FIG. 13 is a block diagram during operation in the offline control mode. , Respectively.

The feature of the second embodiment is that a rotational position estimation unit 130 is provided instead of the rotational position detector 8 of the first embodiment, and the estimated rotational position value _θre is used for the control calculation.
Since other configurations are the same as those of the first embodiment shown in FIGS. 1 and 2, detailed description thereof is omitted here.

Rotational position estimation of the motor 9 is roughly divided into two methods: a method using an induced voltage and a method of directly estimating a position using a high frequency voltage when the motor 9 has saliency. The former method can estimate the rotational position only from the electrical information, but cannot estimate the position in a low speed region where the induced voltage is low. On the other hand, the latter method can estimate the position from the low speed range to the zero speed range, but it is necessary to apply a high frequency voltage that may cause noise and vibration.

For this reason, the rotational position of the motor 9 is generally determined by setting a certain speed threshold ω _sh and using a high-frequency voltage in a low speed range where the speed ω _{re of the} motor 9 is lower than the speed threshold ω _sh. However, in the middle speed range higher than the speed threshold value ω _sh, a method using an induced voltage is adopted, and both methods are often switched and used.

Therefore, in the second embodiment, the first speed threshold value ω _{re_low} for switching the control mode is made to coincide with the switching speed threshold value ω _sh for using the induced voltage and using the high frequency, that is, ω _sh (switching). (Speed threshold) = ω _re — _low (first speed threshold). Therefore, the control unit 150 calculates a rotational position estimation value θ _re by adopting a method of using a high frequency voltage in a low speed region equal to or lower than the first speed threshold value ω _{re_low with} respect to the rotational position estimation unit 130. in the first speed threshold omega _{Re_low} medium speeds or greater than calculates the rotational position estimate theta _re employ a method of utilizing an induced voltage. As described above, the control unit 150 controls the rotational position estimating unit 130 so that the calculation method of the rotational position estimated value θ _re is switched with the first speed threshold value ω _{re_low} as a boundary.

In this way, in the first speed threshold omega _{Re_low} following the low-speed range, the rotational position estimator 130 is thus to estimate the rotational position estimate theta _re using a high frequency voltage, in which case, torque ripple suppression The unit 80 operates in the offline control mode, and can prevent the torque ripple suppression unit 80 from adversely using the rotational position estimation value θ _re in the control calculation in the low speed range.

Further, in the high speed range _{equal to} or higher than the first speed threshold value ω _{re — low} , the rotational position estimation unit 130 estimates the rotational position estimation value θ _re using the induced voltage. In this case, the torque ripple suppression unit 80 Since the operation is performed in the online control mode or the learning control mode, the torque ripple suppression unit 80 can be prevented from having an adverse effect when the rotational position estimation value θ _re is used for the control calculation in a high speed range, and an appropriate suppression control parameter can be obtained. Learning is possible.

Other configurations and operational effects are the same as in the case of the first embodiment, and detailed description thereof is omitted here.

Embodiment 3 FIG.
Since the configuration of the motor control apparatus in the third embodiment is the same as that of the first embodiment shown in FIGS. 1 and 2, detailed description thereof will be omitted here.

First speed for switching this feature the third embodiment, the control mode using the load device and not shown and is connected to it and the motor 9 is a speed omega _{Re_v} that resonates with certain margin rate omega _{Re_m} The threshold value _{ωre_low} is set. That is, _{ωre_low} (first speed threshold) = _{ωre_v} (speed at which the motor and the load device resonate) + _{ωre_m} (margin speed) is set.

As a result, only when the torque ripple of the motor 9 itself becomes dominant while avoiding the influence of mechanical resonance, it operates as the online control mode or the learning control mode, so that appropriate suppression control parameters can be learned. Become.

Embodiment 4 FIG.
Since the basic configuration of the motor control apparatus according to the fourth embodiment is the same as that of the first embodiment shown in FIGS. 1 and 2, detailed description thereof is omitted here.

A feature of the fourth embodiment is that a temperature detector (not shown) for detecting the temperature t _m is provided for the motor 9 and a temperature threshold value t _{m_high} is set for the detected temperature t _m . Then, the control unit _150, so that to operate as an offline control mode in the case of _{t m_high <t m.}

This makes it possible to operate in the online control mode or the learning control mode while avoiding a high temperature region in which the characteristics of the motor 9 greatly change, so that appropriate suppression control parameters can be learned.

FIG. 14 is a flowchart showing an operation sequence when the control unit 150 selects and switches three control modes based on the switching condition in the fourth embodiment.

In FIG. 14, compared with FIG. 6, the determination of the switching condition related to the temperature t _{m in} step S <b> 202 is added to the determination of the transition from the online control mode to the learning control mode. The mode (step S101) is shifted to the learning control mode (step S202) only when the mode is true.

The motor control device of the present invention is not limited to the configurations of the first to fourth embodiments described above, and each of the first to fourth embodiments described above can be used without departing from the spirit of the present invention. They can be freely combined, or the configurations of Embodiments 1 to 4 can be modified or omitted as appropriate.

Embodiment 5 FIG.
FIG. 16 is a configuration diagram showing an example in which the motor control device of the first to fourth embodiments is applied to control a motor that rotates a drive sheave 205 provided in a hoist that raises and lowers an elevator car. is there.

In the elevator according to the fifth embodiment, a car 203 and a counterweight 204 are wound around a drive sheave 205 as a hoisting machine via a rope 202 and connected. The drive sheave 205 is connected to the rotation shaft of the PM motor 9 and is driven to rotate by the PM motor 9. The elevator also includes a rotational position detector 8 and a control device 201 for driving and controlling the PM motor 9 to raise and lower the car 203 in the hoistway.

The control device 201 in this case is composed of the remaining portions excluding the PM motor 9 and the rotational position detector 8 in FIGS. 1 and 2, and the basic configuration is the implementation shown in FIGS. 1 and 2. Therefore, detailed description of the configuration is omitted here.

The feature of the fifth embodiment is that a weight detector (not shown) is provided for the car 203, and a weight threshold value M _{m_high} is set in advance for the _car weight Mm to be detected and the weight Mw of the counterweight 204. The unit 150 is configured to operate as the offline control mode when | M _{m_high} −Mw | <| M _{m ”} −Mw |.

If heavier than the weight there is a car weight M _m is. The PM motor 9 is driven with a high torque from the start. That is, there may be a case where a current exceeding the current threshold value i _{q_hys} (> i _{q_mg} ) at which a hysteresis minor loop appears from the time of startup is required.

Therefore, in the fifth embodiment, when it can be predicted in advance that such a hysteresis minor loop will appear, it can be operated in advance as an offline control mode, and thereafter, it shifts to an online control mode or a learning control mode. Whether or not it is determined _twice based on the weight threshold value M _{m_high} and the current threshold value i _{q_hys} , so that it is possible to learn an appropriate suppression control parameter more safely.

In the fifth embodiment, an operation sequence when the control unit 150 selects and switches between the three control modes is shown in the flowchart of FIG. Reference sign S means a processing step.
In FIG. 17, when compared with FIG. 6, the determination of the switching condition regarding the car weight Mm in step S <b> 203 is added as the determination of the transition from the offline control mode to the online control mode, and the determination result in step S <b> 203 is negative. Shifts to the offline control mode (step S101), and to the online control mode (step S103) only when it is true.

The elevator according to the fifth embodiment has been described on the assumption that the motor control device having the configuration of the first embodiment is provided. However, the present invention is not limited to this, and the motor having the configurations of the other second to fourth embodiments. It is possible to apply a control device.

Claims (9)

1. An AC motor, a current detection unit that detects a current of at least two of the three phases, a current control unit that generates a voltage command value in the control coordinate axis using the current detection value detected by the current detection unit, and a voltage A torque estimation unit that estimates the torque of the AC motor based on the command value and the current detection value; and a torque ripple suppression unit that generates a suppression command that suppresses the torque ripple of the AC motor based on the estimated torque estimated by the torque estimation unit; A suppression control parameter storage unit that stores the suppression control parameter for generating the suppression command in association with the speed of the AC motor and the current command value, and
   In accordance with the switching condition calculated from the magnetic characteristics of the AC motor, an online control mode in which torque ripple suppression is performed by the torque ripple suppression unit, and torque ripple suppression by the torque ripple suppression unit, and at the same time, a suppression control parameter in the suppression control parameter storage unit A control unit that executes an operation sequence for selecting one of three control modes, namely, a learning control mode that stores torque and an offline control mode that performs torque ripple suppression using the suppression control parameter stored in the suppression control parameter storage unit A motor control device.
2. 2. The motor control device according to claim 1, wherein the control unit does not select the learning control mode when the operation sequence is executed and the magnetic characteristic of the magnetic flux with respect to the current of the AC motor forms a hysteresis minor loop. 3. .
3. When the control unit executes the operation sequence, a current threshold value or a torque threshold value corresponding to a condition in which a magnetic characteristic of magnetic flux with respect to the current of the AC motor forms a hysteresis minor loop is set, and the current threshold value or the torque is set. The motor control device according to claim 1, wherein the learning control mode is selected according to a threshold value.
4. The control unit, when executing the operation sequence, selects one of the three control modes according to a speed threshold value calculated from a transfer characteristic from a torque command value to a torque estimation value. The motor control device according to claim 3.
5. When the speed estimation unit is installed in the AC motor, the control unit selects one of the three control modes according to the operation condition of the speed estimation unit when executing the operation sequence. The motor control device according to any one of claims 1 to 3.
6. When the AC motor is connected to an arbitrary load device, the control unit, when executing the operation sequence, selects one of the three control modes according to the speed threshold value calculated from the resonance characteristic of the load device. The motor control device according to any one of claims 1 to 3, wherein one of the two is selected.
7. 7. The control unit according to claim 1, wherein when the operation sequence is executed, the control unit selects one of the three control modes according to a temperature threshold value calculated from a temperature characteristic of the AC motor. The motor control apparatus of Claim 1.
8. The motor control device according to any one of claims 1 to 7, a cage, a counterweight, a rope connecting the cage and the counterweight, and rotation by the driving force of the AC motor And a drive sheave around which the rope is wound.
9. The said control part selects one of said three control modes according to the weight threshold value computed based on the weight of the said cage | basket, and the weight of the said counterweight, when performing the said operation | movement sequence. 8. The elevator according to 8.

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