JP2006197769A - Control unit of ac rotary machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control unit of an AC rotary machine capable of surely reducing the speed even if an angular speed instruction value abruptly changes from a high rotational angular speed to around zero speed, and capable of determining that a switch is near the zero speed even if the resistance value of an AC rotary machine changes due to heating or the like. <P>SOLUTION: The control unit includes a speed estimating means 5 which outputs a first estimated angular speed and a first angular frequency for the rotary angular speed of an AC rotary machine 1 based on the current of AC rotary machine 1 which is detected by a current detector 2 and the voltage applied to the AC rotary machine 1 by a power converter 3, and an instruction calculating means 6 which calculates a deviated angular speed from a deviation between the angular speed instruction and the first estimated angular speed and outputs a torque current instruction and power supply angular frequency. The instruction calculating means 6 selects a torque current instruction and power source angular frequency to be outputted based on the value limiting the range of deviation angular speed and the first estimated angular speed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to an AC rotating machine control device for variable speed control of an AC rotating machine.

  The rotational angular velocity detector for variable speed control of an AC rotating machine is desired to be eliminated in terms of price and wiring. In order to solve this problem, in the conventional control device for an AC rotating machine, the estimated rotation of the induction motor based on the current detection means for detecting the primary current of the induction motor and the primary voltage and the primary current supplied to the induction motor. Rotational angular velocity estimation means for calculating the angular velocity, and speed control means for inputting the rotational angular velocity command of the induction motor and controlling the primary voltage based on the estimated rotational angular velocity so that the estimated rotational angular velocity follows the rotational angular velocity command. The rotational angular velocity estimation means includes an adaptive observer that calculates the estimated secondary magnetic flux, estimated primary current, and estimated rotational angular speed of the induction motor based on the primary current and the primary voltage, and the estimated rotational angular speed obtained from the adaptive observer. And a gain calculator that calculates the feedback gain in the adaptive observer based on the AC rotating machine (induction motor) without a rotational angular velocity detector ) The are variable speed control (for example, Patent Document 1).

  Also, a variable speed control device for a conventional AC rotating machine intended for a synchronous motor as an AC rotating machine has been invented. The present invention relates to a current detector for detecting the current of an AC rotating machine (synchronous motor), and a current on a rotating biaxial coordinate (dq axis) that rotates the current obtained by the current detector at an angular frequency. A coordinate converter for coordinate conversion, and a rotation biaxial coordinate (dq) so that the current on the rotation biaxial coordinate (dq axis) follows the current command on the rotation biaxial coordinate (dq axis). A current controller that outputs a voltage command on the axis), a coordinate converter that converts the voltage command on the rotating biaxial coordinates (dq axes) obtained from the current controller into a three-phase voltage command, and Based on the current on the rotating biaxial coordinate (dq axis) and the voltage command on the rotating biaxial coordinate (dq axis), the angular frequency and the estimated current of the AC rotating machine (synchronous motor) An adaptive observer for calculating an estimated rotor magnetic flux and an estimated rotational angular velocity, and the alternating current based on the voltage command And an inverter that applies a voltage to a rotary machine (synchronous motor), and the adaptive observer calculates an angular frequency so that a q-axis component of the estimated rotor magnetic flux becomes zero, and also calculates an estimated rotational angular velocity from a rotational angular angular velocity command. Is output to the speed controller, and the speed controller outputs a q-axis current command based on the deviation between the rotational angular velocity command and the estimated rotational angular velocity (for example, Patent Document 2).

  In such an AC rotating machine control device, the accuracy of estimation of the rotational angular velocity in the vicinity of zero speed is reduced, and there is a problem that the start of the load is delayed. A control device for an AC rotating machine has been invented for the purpose of solving this problem. The AC rotating machine variable speed control device obtains a torque current command and an excitation current command from a speed control system based on the speed estimation of the induction motor, and based on these commands, supplies a current supplied from the inverter to the induction motor by the current control system. A function generator and a changeover switch for generating a constant torque current command instead of a torque current command from the speed control system when the angular velocity command is in the vicinity of zero speed of the induction motor in the speed sensorless vector control device to be controlled And a changeover switch that uses the angular velocity command as a rotational angular velocity detection value instead of the estimated angular velocity when the angular velocity command is in the vicinity of the zero velocity of the induction motor, thereby reducing a control delay near the zero velocity. (For example, patent document 3).

  A power converter for driving the induction motor; current detection means for detecting an alternating current supplied to the induction motor; and a current (of a magnetic flux axis (d-axis) component of the rotating magnetic field coordinate system for the detected alternating current ( Hereinafter, conversion means for converting the d-axis current) and a component orthogonal to the d-axis (hereinafter, q-axis current), first speed estimation means for generating a speed estimation value from the q-axis current, and the speed estimation value In the induction motor drive control device comprising means for controlling the drive of the induction motor based on the above, a second speed estimation means for generating a speed estimate value from the d-axis current command value and the q-axis current command value is provided, When the speed estimation value becomes a predetermined value or less during the deceleration operation, the AC rotating machine that performs stable speed estimation to a low speed range and reliably decelerates by switching to the second speed estimation means and controlling the induction motor Control device invented It is (for example, Patent Document 4).

Japanese Patent Laid-Open No. 11-4599 (page 7, paragraph 0017, FIG. 3) Re-published patent WO02 / 91558 (2 pages 3-14 lines, 16 pages 43-47 lines, FIGS. 1 and 14) JP 2002-142499 A (2 pages, paragraph 0009, paragraph 0011, FIG. 1) JP 2001-238497 A (2-3 pages, paragraph 0006, FIG. 1)

  In the control device for an AC rotating machine as in Patent Document 3, since the angular velocity command is used to determine whether or not it is in the vicinity of zero speed, the angular velocity command value suddenly changes from a high rotational angular velocity to near zero speed. In this case, although the actual rotational angular velocity does not reach the vicinity of the zero speed, the changeover switch determines that the rotation speed is in the vicinity of the zero speed, and the vehicle cannot be decelerated.

  In addition, since a constant torque current command is generated instead of the torque current command when near zero speed, the torque current value becomes a desired value when the angular velocity command changes or when the load inertia is large. There was a problem that the angular velocity commands could not be tracked near zero speed.

  Furthermore, since the angular velocity command was changed to the rotational angular velocity instead of the estimated angular velocity when in the vicinity of the zero velocity, the estimated angular velocity did not match the actual rotational angular velocity when the angular velocity command value changed suddenly and departed from the vicinity of the zero velocity. There was also a problem that switching shock occurred.

  In the control apparatus for an AC rotating machine as in Patent Document 4, it is determined based on the estimated rotational angular speed whether or not the speed is near zero speed. When the resistance value of the AC rotating machine changes due to heat generation or the like, the estimated rotational angular velocity becomes a value different from the actual value. If the resistance value changes, the change-over switch cannot be judged to be near zero speed even though the actual rotational angular speed has reached around zero speed, and stable speed estimation cannot be performed up to the low speed range, so it cannot be decelerated reliably. There was a problem.

  That is, when the switching speed is determined by the angular velocity command as in Patent Document 3 or when the switching speed is determined by the estimated rotational angular speed or not as in Patent Document 4, the switching operation is performed. There was a problem.

  The present invention has been made to solve the above-described problems. The first object is to change the angular velocity command value from a high rotational angular velocity to a value near zero speed, and to change the actual rotational angular velocity to a value near zero speed. The purpose is to solve the problem of being unable to decelerate if not reached, and the problem that the changeover switch cannot be determined to be near zero speed when the resistance value of the AC rotating machine changes due to heat generation, etc. is there.

  Another object of the present invention is to improve the speed response when the angular velocity command changes near zero speed or when the load inertia is large.

  Furthermore, even if the angular velocity command value changes suddenly when it is in the vicinity of the zero speed and the value deviates from the vicinity of the zero speed, the estimated angular velocity is made to coincide with the actual rotational angular velocity, and the purpose is to eliminate the switching shock.

  The control apparatus for an AC rotating machine according to the present invention includes a power converter that applies a voltage to the AC rotating machine, a current detector that detects a current of the AC rotating machine, a current detected from the current detector, and the power. Based on the voltage applied by the converter, the rotational angular velocity of the AC rotating machine is derived from the deviation between the angular velocity command and the first estimated angular velocity, the velocity estimating means for outputting the first estimated angular velocity and the first angular frequency. Command arithmetic means for calculating a deviation angular velocity and outputting a torque current command and a power source angular frequency, the command arithmetic means based on a value limiting the range of the deviation angular velocity and the first estimated angular velocity. The torque current command to be output and the power source angular frequency are selected.

  The control device for the AC rotary machine of the present invention selects a torque current command and a power supply angular frequency that are output by adding a value obtained by restricting the deviation angular velocity to the first estimated angular velocity by the command calculation means. This solves the problem that the angular velocity command value suddenly changes to near zero speed and the motor cannot be decelerated when the actual rotational angular speed does not reach near zero speed, and the resistance value of the AC rotating machine changes due to heat generation. In this case, it is possible to solve the problem that the change-over switch cannot be determined to be near zero speed.

Embodiment 1 FIG.
1 is a diagram showing a configuration of a control device for an AC rotary machine according to Embodiment 1 of the present invention. In FIG. 1, a phase current supplied to an AC rotating machine (induction machine) 1 is detected by a current detector 2. Power is supplied to the AC rotating machine (induction machine) 1 by a power converter 3. The coordinate converter 4 converts the phase current obtained from the current detector 2 into a current on rotating biaxial coordinates (dq axes) rotating at the power source angular frequency ω.
The speed estimator 5 includes a power source angular frequency ω, a current on a rotating biaxial coordinate (dq axis) obtained from the coordinate converter 4, and a voltage on a rotating biaxial coordinate (dq axis) described later. Based on the command, the first angular frequency ω1, the first estimated angular velocity ^ ωr1, and the d-axis estimated magnetic flux (estimated magnetic flux amplitude) ^ φdr on the rotating biaxial coordinates (dq axes) are output. Here, the symbol ^ means an operation value.

The command calculation means 6 is configured so that the angular velocity command ωr * and the d-axis magnetic flux command φdr on the rotational biaxial coordinates (dq axes) so that the rotational angular velocity of the AC rotating machine (induction machine) 1 coincides with the angular velocity command ωr *. Based on *, the first angular frequency ω1, and the first estimated angular velocity ^ ωr1, the q-axis current command iqs * on the rotating biaxial coordinates (dq axes), the power source angular frequency ω, and the second estimated angular velocity ^ Ωr2 is output. Here, the symbol * means the command value.
The magnetic flux controller 7 controls the d-axis current command ids * on the rotating biaxial coordinates (dq axes) so that the d-axis estimated magnetic flux ^ φdr obtained from the speed estimating means 5 coincides with the d-axis magnetic flux command φdr *. Is output.

The control means 8 is based on the d-axis current command ids * on the rotating biaxial coordinates (dq axes), the q-axis current command iqs * on the rotating biaxial coordinates (dq axes), and the power source angular frequency ω. Thus, a phase voltage command to be supplied to the power converter 3 is output. The control means 8 includes a current controller 9, an integrator 10, and a coordinate converter 11.
The current controller 9 uses the rotation biaxial coordinates (dq axes) obtained from the coordinate converter 4 to the d axis current command ids * on the rotation biaxial coordinates (dq axes) obtained from the magnetic flux controller 7. ) The two d-axis current ids coincide with each other, and the two rotation axes obtained from the coordinate converter 4 to the q-axis current command iqs * on the rotation two-axis coordinates (dq axes) obtained from the command calculation means 6 The voltage command on the rotating biaxial coordinates (dq axes) described above is output so that the q axis currents iqs on the coordinates (dq axes) match.
The integrator 10 integrates the power supply angular frequency ω obtained from the command calculation means 6 to calculate the phase θ. Based on the phase θ, the coordinate converter 11 converts the voltage command on the rotating biaxial coordinates (dq axes) into a phase voltage command to be supplied to the power converter 3 and outputs the phase voltage command.

  In FIG. 1, when the switching signal SW1 is FALSE, the speed estimation means 5 uses the rotation command input from the coordinate converter 4 and the voltage command on the rotation biaxial input from the control means 8 to the first estimated angular speed ^ ωr1. The first estimated angular velocity {circumflex over (ω)} r1 is calculated based on the current on the two axes and the power supply angular frequency ω input from the command calculation means 6. When the switching signal SW1 is TRUE, the speed estimation means 5 replaces the first estimated angular speed ^ ωr1 with the second estimated angular speed ^ ωr2 input from the command calculation means 6.

FIG. 2 is a diagram showing a configuration of command calculation means 6 in the control device for an AC rotary machine according to Embodiment 1 of the present invention.
In FIG. 2, the switching signal calculator 20 outputs a switching signal SW1 based on the estimated angular velocity ^ ωr1 obtained from the velocity estimating means 5, the deviation angular velocity Δωr described later, and a first q-axis current command iqs1 * described later. To do.
The speed response calculator 21 prepares in advance a response ωsc (rad / s) that the rotational angular speed of the AC rotating machine (induction machine) 1 should follow the angular speed command ωr * as a design value, and the response ωsc (rad / s) Based on s), the second estimated angular velocity ^ ωr2 is calculated. As will be described later, when the speed controller 26 is given by proportional integral control, the response that the rotational angular velocity of the AC rotating machine (induction machine) 1 should follow the angular velocity command ωr * is a secondary system. The speed response calculator 21 gives the operation of the speed controller 26 as a primary system of the expression (1) in which the high frequency band is omitted so that the high frequency band is simplified.
^ ωr2 ＝ ωsc ÷ (s + ωsc) × ωr * (1)
Where s: Laplace operator

The relationship of equation (2) is established between the rotational angular velocity ωr (rad / s) and the output torque τm (Nm).
ωr = Pm ÷ (Jm × s) × τm (2)
However, Pm: Number of pole pairs of AC rotating machine (induction machine) 1 Jm: Total inertia of AC rotating machine (induction machine) 1 and load (kgfm2)
s: Laplace operator The torque command calculator 22 calculates the torque command τm * by the calculation of the equation (3) using the relationship of the equation (2) based on the second estimated angular velocity ^ ωr2, the inertia Jm, and the number of pole pairs Pm. Is output.
τm * = (Jm × s) ÷ Pm × ^ ωr2 (3)

The relationship of the formula (4) is established between the q-axis current iqs on the rotating biaxial coordinates (dq axis) and the output torque τm.
τm = Pm × M ÷ Lr × φdr × iqs (4)
However, Lr: primary inductance M of AC rotating machine (induction machine) 1: mutual inductance coefficient calculator 23 of AC rotating machine (induction machine) 1 is based on d-axis magnetic flux command φdr * and torque command τm * (4 ) The second q-axis current command iqs2 * is output by the calculation of the equation (5) using the relationship of the equation (5).
iqs2 * = Lr ÷ (Pm × M × φdr *) × τm * (5)

The relationship of the formula (6) is established among the power source angular frequency ω, the rotational angular velocity ωr, the q-axis current iqs, and the secondary magnetic flux φdr.
ω = ωr + M × Rr ÷ Lr × iqs ÷ φdr (6)
The angular frequency calculator 24 uses the relationship of Equation (6) based on the d-axis magnetic flux command φdr *, the second estimated angular velocity ^ ωr2, and the second q-axis current command iqs2 *. The second angular frequency ω2 is calculated by calculation.
ω2 = ^ ωr2 + M × Rr ÷ Lr × iqs * ÷ φdr * (7)
The subtracter 25 subtracts the first estimated angular velocity ^ ωr1 from the angular velocity command ωr * and outputs a deviation angular velocity Δωr.
The speed controller 26 amplifies the deviation angular speed Δωr and outputs it as a first q-axis current command iqs1 *. In the first embodiment, the speed controller 26 gives amplification of the deviation angular velocity Δωr by proportional integral control.

The switch 27 receives the first angular frequency ω1, the second angular frequency ω2, the first q-axis current command iqs1 *, and the second q-axis current command iqs2 *, and based on the switching signal SW1, the power supply angle Outputs frequency ω and q-axis current command iqs *.
Specifically, when SW1 is FALSE, the power supply angular frequency ω is given by the first angular frequency ω1, and at the same time, the q-axis current command iqs * is given by the first q-axis current command iqs1 *. When SW1 is TRUE, the power supply angular frequency ω is given by the second angular frequency ω2, and at the same time, the q-axis current command iqs * is given by the second q-axis current command iqs2 *.

FIG. 3 is a diagram showing the configuration of the switching signal calculator 20 in the command calculation means 6 according to Embodiment 1 of the present invention. In FIG. 3, the limiter 30 limits the amplitude of the input deviation angular velocity Δωr. The output of the limiter 30 and the first estimated angular velocity ^ ωr1 are added by the adder 31, and the output is input to the filter 32.
The filter 32 takes the output of the adder 31 as an input, performs a first-order lag calculation of the break frequency at the angular frequency ωF for the purpose of preventing chattering, and outputs it as a judgment speed ^ ωr3. The determiner 33 determines whether or not the AC rotating machine (induction machine) 1 is near zero speed based on the determination speed ^ ωr3. If it is determined that it is near zero speed, TRUE is output, and if it is determined that it is outside the vicinity of zero speed, FALSE is output.

When the input of the limiter 30 matches the output, the input of the filter 32 matches the angular velocity command ωr *, and when the input of the limiter 30 does not match the output, the input of the filter 32 matches the first estimated angular velocity ^ ωr1. A value obtained by adding the deviation angular velocity Δωr. The determination speed ^ ωr3 is a first-order lag calculation with respect to the input of the filter 32.
In the conventional control device for an AC rotary machine, when the resistance value changes, the estimated rotational angular velocity has an error, and the changeover switch is in the vicinity of the zero velocity even though the actual rotational angular velocity has reached the zero velocity. There was a problem that could not be determined. In the first embodiment, the limit range of the limiter 30 is set to be larger than the estimated speed error caused by the resistance change, so that the judgment speed ^ ωr3 in the vicinity of the zero speed is a value obtained by adding the filter 32 to the angular speed command ωr *. Therefore, there is an effect that reliable switching can be performed without being affected by the presence or absence of an error in the estimated rotational speed.

  When the AC rotating machine is an induction machine, the slip frequency increases and the angular frequency ω also increases if the load is large even in the vicinity of zero speed. In the control device for an AC rotating machine, there is a problem that the estimation accuracy of the rotational angular velocity in the vicinity of zero speed is lowered, and thus there is a problem that the start of the load is delayed. This phenomenon is remarkable when the power source angular frequency ω is small. Conversely, when the power supply angular frequency ω is large to some extent, the estimation accuracy of the rotational angular velocity hardly decreases. Therefore, the power supply angular frequency ω is given by the second angular frequency ω2 only in the region where the power supply angular frequency ω is small, and at the same time, the q-axis current command iqs * is given by the second q-axis current command iqs2 *.

By providing the determination unit 34 and the logical product calculator 35, the power supply angular frequency ω is given by the second angular frequency ω2 only in the region where the power supply angular frequency ω is small even near the zero speed, and at the same time, the q-axis current command iqs * Can be given by the second q-axis current command iqs2 *. The determiner 34 determines whether or not the first q-axis current command iqs1 * is a light load on the AC rotating machine (induction machine) 1. If it is determined that the load is light, TRUE is output. If it is determined that the load is not light, FALSE is output.
The AND operator 35 performs an AND operation on the outputs of the determiner 33 and the determiner 34. That is, when the determiner 33 and the determiner 34 output TRUE at the same time, the AND operator 35 outputs TRUE, and otherwise, the AND operator 35 outputs FALSE.

FIG. 4 is a waveform showing internal variables in the control device for an AC rotary machine according to Embodiment 1 of the present invention. The total inertia Jm is 20 times the inertia of the AC rotating machine (induction machine) 1. In FIG. 4, the horizontal axis represents time (seconds), the vertical axis represents the rotational angular velocity (r / min), and the angular velocity command ωr *, the first estimated angular velocity ^ ωr1, and the determination velocity ^ ωr3 are plotted. The AC rotating machine (induction machine) 1 is rotating at 200 r / min until time 1 second, and the angular velocity command ωr * is stepped from 200 r / min to 0 r / min at time 1 second.
The magnitude of torque that can be output by the AC rotating machine (induction machine) 1 is finite. When the inertia is large, the actual rotational angular velocity cannot be reduced to zero stepwise. The first estimated angular velocity ^ ωr1 in the figure correctly estimates the actual rotational angular velocity (not shown), and when the inertia is 20 times, it reaches the vicinity of zero speed around 6 seconds. The judgment speed ^ ωr3 is generated by adding the value that limits the deviation angular speed Δωr to the first estimated angular speed ^ ωr1, so the maximum difference between the judgment speed ^ ωr3 and the first estimated angular speed ^ ωr1 is the deviation. This is the limit value of the angular velocity Δωr. In the first embodiment, the limit value of the deviation angular velocity Δωr is set to 60 r / min. At the time of 1 second when the angular velocity command changes to 0, the determination speed ^ ωr3 in the figure has a maximum difference of 60 r / min from the first estimated angular velocity ^ ωr1.

In the conventional AC rotating machine control device, since the rotational angular velocity is determined to be near zero based on the rotational angular velocity command, the inertia is large (when the inertia is 20 times in FIG. 4), In spite of not sufficiently decelerating, it is erroneously determined as zero speed at the time of FIG. 4 (a), and there is a problem that deceleration torque cannot be output.
In the first embodiment, it is determined that the rotational angular velocity is near zero based on the determination speed ^ ωr3. According to the first embodiment, the switching signal calculator 20 determines that the determination speed ^ ωr3 is near zero speed at the time of (b) in FIG. That is, even when the inertia is large (in FIG. 4, the inertia is 20 times), the switching signal calculator 20 does not erroneously determine that the speed is zero at the time of FIG. Judged as near the speed. As a result, it is possible to solve the problem that the deceleration torque cannot be output if the inertia is large when the angular velocity command is decelerated by a step change.

  As described above, in the first embodiment, the switching signal calculator 20 adds the value obtained by limiting the deviation angular velocity Δωr to the first estimated angular velocity ^ ωr1 to generate the determination velocity ^ ωr3. The problem that the angular velocity command value suddenly changes near zero speed and the actual rotational angular velocity does not reach near zero speed cannot be reduced can be solved.

FIG. 5 is a waveform showing internal variables and actual rotational angular velocities of the control apparatus for an AC rotary machine according to Embodiment 1 of the present invention. FIG. 5 shows the state of the angular velocity command ωr *, the second estimated angular velocity ^ ωr2, the second q-axis current command iqs2 *, and the actual rotational angular velocity ωr. The total inertia Jm is an AC rotating machine ( (Induction machine) 1 inertia unit.
The switching signal calculator 20 determines that the speed is near zero if the rotational angular velocity is 60 r / min, and SW1 is set to TRUE. In the figure, the angular velocity command ωr * is stepped from 0 to 60 r / min at a time of 0.1 second, and the switching signal calculator 20 gives the power source angular frequency ω at the second angular frequency ω2 and q The shaft current command iqs * is given by the second q-axis current command iqs2 *.
The speed response calculator 21 prepares in advance as a design value a response ωsc (rad / s) that the rotational angular velocity of the AC rotary machine (induction machine) 1 should follow the angular velocity command ωr *. The response ωsc (rad / s) is set to 50 rad / s, and the second estimated angular velocity ^ ωr2 is calculated based on this response.
The torque command calculator 22 outputs a torque command τm * by the calculation of equation (3) based on the second estimated angular velocity ^ ωr2, the inertia Jm, and the pole pair number Pm, and the coefficient calculator 23 calculates τm * ( A value multiplied by Lr ÷ Pm × M × φdr *) is output as the second q-axis current command iqs2 *.

As shown in FIG. 5, when the angular velocity command changes stepwise near zero speed, the second estimated angular velocity is a response 50 (rad / s) that the rotational angular velocity of the AC rotating machine (induction machine) 1 should follow. Follow. The second q-axis current command iqs2 * outputs a desired value during the acceleration of the second estimated angular velocity by the calculation of equation (3) considering the rate of change of the second estimated angular velocity. Since SW1 of the switching signal calculator 20 is TRUE, the switching unit 27 gives the q-axis current command iqs * by the second q-axis current command iqs2 *.
The second estimated angular velocity follows the angular velocity command with the response 50 (rad / s) that the rotational angular velocity of the AC rotating machine (induction machine) 1 should follow, and the q-axis current command iqs with the second q-axis current command iqs2 *. As shown in FIG. 5, the actual rotational angular velocity ωr of the AC rotating machine (induction machine) 1 is the angular velocity with a response 50 (rad / s) to be followed, as in the second estimated angular velocity ^ ωr2, as shown in FIG. Follow the command.

FIG. 6 is a waveform showing internal variables and actual rotational angular velocities of the control apparatus for an AC rotary machine according to Embodiment 1 of the present invention. FIG. 6 shows an angular velocity command ωr *, a second estimated angular velocity ^ ωr2 and a second q-axis current command iqs2 * when the total inertia Jm is 10 times the inertia of the AC rotating machine (induction machine) 1 alone. This shows the actual rotational angular velocity ωr, and the conditions are the same as in FIG. 5 except for the total inertia Jm.
Since the total inertia Jm is 10 times that in FIG. 5, the torque command τm * is 10 times that in FIG. Command iqs2 * is also 10 times. When the inertia is large, it is necessary to increase the q-axis current command in order to obtain the same speed response. The torque command calculator 22 considers the response and the total inertia Jm that the actual rotational angular velocity ωr should follow in the process of calculating the equation (3). As a result, the second q-axis current command iqs2 * is also a value that takes into account the response that the actual rotational angular velocity ωr should follow and the total inertia Jm.

  As described above, in the first embodiment, the speed response computing unit 21 uses the second response ωsc (rad / s) based on the response ωsc (rad / s) that the rotational angular velocity of the AC rotating machine (induction machine) 1 should follow the angular velocity command ωr *. The estimated angular velocity ^ ωr2 is calculated, the torque command calculator 22 outputs a torque command τm * considering the response that the actual rotational angular velocity ωr should follow and the total inertia Jm, and the coefficient calculator 23 calculates τm * (Lr ÷ Pm). * M × φdr *) times the value is output as the second q-axis current command iqs2 *, so the response that the rotational angular velocity should follow even when the angular velocity command changes near zero speed or when the load inertia is large This has the effect of following the angular velocity command with ωsc (rad / s).

FIG. 7 is a waveform showing internal variables and actual rotational angular velocities of the control apparatus for an AC rotary machine according to Embodiment 1 of the present invention. FIG. 7 shows the state of the angular velocity command ωr *, the first and second estimated angular velocities, the first and second q-axis current commands, and the actual rotational angular velocity ωr, and the total inertia Jm is the AC rotating machine. (Induction machine) 5 times the inertia unit of 1
In FIG. 7, the switching signal SW1 output by the switching signal calculator 20 at around 0.12 seconds changes from TRUE to FALSE. Therefore, before the time 0.12 seconds, the switch 27 gives the power source angular frequency ω at the second angular frequency ω 2 and simultaneously gives the q-axis current command iqs * as the second q-axis current command iqs 2 *. The speed estimation means 5 replaces the first estimated angular speed ^ ωr1 with the second estimated angular speed ^ ωr2 input from the command calculation means 6. Further, after the time of 0.12 seconds, the switch 27 gives the power source angular frequency ω at the first angular frequency ω1 and simultaneously gives the q-axis current command iqs * as the first q-axis current command iqs1 *. Note that the first q-axis current command iqs1 * immediately after switching is given by the second q-axis current command iqs2 * immediately before switching.
Further, the speed estimation means 5 is configured to input the first estimated angular velocity ^ ωr1 on the rotation biaxial voltage command input from the control means 8, the rotation biaxial current input from the coordinate converter 4 and the command calculation means 6. The first estimated angular velocity {circumflex over (ω)} r1 is calculated on the basis of the power supply angular frequency ω input from. Note that the first estimated angular velocity ^ ωr1 immediately after switching is the second estimated angular velocity ^ ωr2 immediately before switching.
With the above operation, as shown in FIG. 7, even when the angular velocity command value changes suddenly and deviates from the vicinity of zero velocity, the actual rotational angular velocity can be smoothly accelerated.

As described above, according to the first embodiment, in the vicinity of the zero speed, the switching signal calculator 20 outputs the TRUE switching signal SW1, and the speed estimation means 5 performs the command calculation on the first estimated angular velocity ^ ωr1. Since the second estimated angular velocity ^ ωr2 input from the means 6 is replaced, even if the actual rotational angular velocity and the angular velocity command do not match immediately after the switching signal SW1 is switched, the actual rotational angular velocity and the second estimated angular velocity. The angular velocity ^ ωr2 matches.
Therefore, even when the angular velocity command value changes suddenly and deviates from the vicinity of the zero speed, an effect that the AC rotating machine (induction machine) 1 can be driven without switching shock can be obtained.
Further, by setting the limit range of the limiter 30 to be larger than the estimated speed error caused by the resistance change, the judgment speed ^ ωr3 in the vicinity of the zero speed becomes a value through the filter 32 to the angular speed command ωr *. There is an effect that reliable switching can be performed without being influenced by the presence or absence of an error in the estimated rotational speed.

Embodiment 2. FIG.
FIG. 8 is a diagram showing a configuration of command calculation means 6a in the control device for an AC rotary machine according to Embodiment 2 of the present invention.
The command calculation means 6 according to the first embodiment uses the switching signal calculator 20 based on the estimated angular velocity ^ ωr1 obtained from the speed estimation means, the deviation angular velocity Δωr, and the first q-axis current command iqs1 *. Although SW1 was output, in order to simplify the configuration, the first q-axis current command iqs1 * may be excluded from the requirements of the switching signal SW1. Specifically, the command calculation means 6 in FIG. 1 is replaced with a command calculation means 6a (not shown).
8, reference numerals 21 to 27 are the same as those in FIG. 2 of the first embodiment, and a description thereof will be omitted. The switching signal calculator 20a outputs a switching signal SW1 based on the estimated angular velocity ^ ωr1 obtained from the velocity estimating means 5 and the deviation angular velocity Δωr.

FIG. 9 is a diagram showing a configuration of the switching signal calculator 20a in the command calculation means 6a according to Embodiment 2 of the present invention. 9 omits the determiner 34 and the AND operator 35 from the configuration of the switching signal calculator 20 shown in FIG. 3 of the first embodiment, and uses the output signal of the determiner 33 as the switching signal SW1. The point of output is different.
That is, the switching signal calculator 20a determines whether or not the AC rotating machine (induction machine) 1 is near zero speed based on the determination speed ^ ωr3. If it is determined that it is near zero speed, TRUE is output, and if it is determined that it is outside the vicinity of zero speed, FALSE is output.

  Even in the above configuration, the switching signal calculator 20a adds the value obtained by limiting the deviation angular velocity Δωr to the first estimated angular velocity ^ ωr1 to generate the determination velocity ^ ωr3 as in the first embodiment. Thus, there is an effect that the problem that the angular velocity command value suddenly changes to near zero speed and the vehicle cannot be decelerated when the actual rotational angular velocity does not reach near zero speed can be solved.

Embodiment 3 FIG.
When the d-axis magnetic flux command φdr * is kept constant, the d-axis current command ids * may be given by the equation (8) in which the transient term is omitted.
ids * = φdr * ÷ M (8)
When the d-axis magnetic flux command φdr * is kept constant from the equation (8), the d-axis current command ids * command is also constant.
In the first and second embodiments, the magnetic flux controller 7 rotates the biaxial coordinates (dq axes) so that the d-axis estimated magnetic flux ^ φdr obtained from the speed estimating means 5 coincides with the d-axis magnetic flux command φdr *. Although the upper d-axis current command ids * is output, the d-axis current command ids * may be given as a predetermined value.
FIG. 10 is a diagram showing a configuration of an AC rotary machine control device according to Embodiment 3 of the present invention. In FIG. 10, 1 to 5 and 8 to 11 are the same as those in FIG.
The command calculation means 6b is configured so that the angular velocity command ωr * and the d-axis on the rotation biaxial coordinates (dq axes) set in advance so that the rotational angular velocity of the AC rotating machine (induction machine) 1 coincides with the angular velocity command ωr *. Based on the current command ids *, the first angular frequency ω1, and the first estimated angular velocity ^ ωr1, the q-axis current command iqs *, the power supply angular frequency ω, and the second on the rotating biaxial coordinates (dq axes) The estimated angular velocity ^ ωr2 is output.

FIG. 11 is a diagram showing a configuration of command calculation means 6b in the control device for an AC rotary machine according to Embodiment 3 of the present invention. 11, 20a, 21, 22, 25, 26, and 27 are the same as those in FIG. 8, and the description thereof is omitted.
When the d-axis current ids is constant, the relationship of the equation (9) is established between the q-axis current iqs on the rotating biaxial coordinates (dq axes) and the output torque τm.
τm = Pm × M2 ÷ Lr × ids × iqs (9)
However, Lr: primary inductance M of AC rotating machine (induction machine) 1: mutual inductance coefficient calculator 23b of AC rotating machine (induction machine) 1 is based on d-axis current command ids * and torque command τm * (9 ) The second q-axis current command iqs2 * is output by the calculation of the equation (10) using the relationship of the equation (10).
iqs2 * = Lr ÷ (Pm × M2 × ids *) × τm * (10)
When the d-axis current ids is constant, the relationship of the formula (11) is established among the power source angular frequency ω, the rotational angular velocity ωr, the q-axis current iqs, and the d-axis current ids.
ω = ωr + Rr ÷ Lr × iqs ÷ ids (11)
The angular frequency calculator 24b uses the relationship of the equation (11) based on the d-axis current command ids *, the second estimated angular velocity ^ ωr2, and the second q-axis current command iqs2 *. The second angular frequency ω2 is calculated by calculation.
ω2 = ^ ωr2 + Rr ÷ Lr × iqs * ÷ ids * (12)

  Even in the above configuration, the switching signal calculator 20b adds the value obtained by limiting the deviation angular velocity Δωr to the first estimated angular velocity ^ ωr1 to generate the determination velocity ^ ωr3 as in the first embodiment. From the angular velocity, the angular velocity command value suddenly changes to near zero speed, and there is an effect that it is possible to solve the problem that it becomes impossible to decelerate when the actual rotational angular velocity does not reach near zero speed.

Embodiment 4 FIG.
FIG. 12 is a diagram showing a configuration of a control device for an AC rotary machine according to Embodiment 4 of the present invention. 12, 2 to 4 and 8 to 11 are the same as those in FIG.
The current detector 2 detects the phase current supplied to the AC rotating machine (synchronous machine) 1c. The power converter 3 supplies power to the AC rotating machine (synchronous machine) 1c.
The speed estimation means 5c includes the power supply angular frequency ω, the current on the rotating biaxial coordinates (dq axes) obtained from the coordinate converter 4, the voltage command on the rotating biaxial coordinates (dq axes), Based on the above, the angular frequency ω1 of the AC rotating machine (synchronous machine) 1c and the first estimated angular velocity ^ ωr1 are output.
The command calculation means 6c is based on the angular velocity command ωr *, the first angular frequency ω1, and the first estimated angular velocity ^ ωr1 so that the rotational angular velocity of the AC rotating machine (synchronous machine) 1c matches the angular velocity command ωr *. The q-axis current command iqs * on the rotating biaxial coordinates (dq axes), the power supply angular frequency ω, and the second estimated angular velocity ωr2 are output.

  When the switching signal SW1 is FALSE, the speed estimation means 5c uses the first estimated angular speed ^ ωr1 as the voltage command on the rotation biaxial input from the control means 8 and the rotation biaxial input from the coordinate converter 4. The first estimated angular velocity {circumflex over (ω)} r1 is calculated based on the current and the power supply angular frequency ω input from the command calculation means 6. When the switching signal SW1 is TRUE, the speed estimation means 5c replaces the first estimated angular speed ^ ωr1 with the second estimated angular speed ^ ωr2 input from the command calculation means 6c.

FIG. 13 is a diagram showing a configuration of command calculation means 6c in the control apparatus for an AC rotary machine according to Embodiment 4 of the present invention. In FIG. 13, 20a, 21, 22, 25, and 26 are the same as those in FIG.
Since the AC motor (synchronous machine) 1c is a synchronous machine, the relationship of the equation (13) is established between the q-axis current iqs on the rotating biaxial coordinates (dq axes) and the output torque τm.
τm = Pm × φf × iqs (13)
However, φf: the rotor magnetic flux amplitude coefficient calculator 23c of the AC rotating machine (synchronous machine) 1c, based on the torque command τm *, calculates the second q by the calculation of the expression (14) using the relationship of the expression (13). The shaft current command iqs2 * is output.
iqs2 * = 1 ÷ (Pm × φf) × τm * (14)
Since the AC motor (synchronous machine) 1c is a synchronous machine, the power angular frequency ω matches the rotational angular velocity ωr. Based on this, the second angular frequency ω2 is given by the second estimated angular velocity ωr2.
The switch 27c inputs the first angular frequency ω1, the second angular frequency ω2, the first q-axis current command iqs1 *, and the second q-axis current command iqs2 *, and based on the switching signal SW1, the power supply angle Outputs frequency ω and q-axis current command iqs *.
Specifically, when SW1 is FALSE, the power supply angular frequency ω is given by the first angular frequency ω1, and at the same time, the q-axis current command iqs * is given by the first q-axis current command iqs1 *. When SW1 is TRUE, the power supply angular frequency ω is given by the second angular frequency ω2, and at the same time, the q-axis current command iqs * is given by the second q-axis current command iqs2 *.

  With the above configuration, even if the AC rotating machine is a synchronous machine, the switching signal calculator 20c adds a value obtained by limiting the deviation angular velocity Δωr to the first estimated angular velocity ^ ωr1 in the same manner as in the above-described embodiment. Since ωr3 is generated, it is possible to solve the problem that the angular velocity command value suddenly changes to near zero speed from a high rotational angular velocity, and it becomes impossible to decelerate when the actual rotational angular velocity does not reach near zero speed. is there.

  In the fourth embodiment, even if the AC rotating machine is a synchronous machine, the speed response computing unit 21 responds to the angular speed command ωr * with the response ωsc (rad / rad) that the rotational angular speed of the AC rotating machine (synchronous machine) 1c should follow. s), the second estimated angular velocity ^ ωr2 is calculated, and the torque command calculator 22 outputs a torque command τm * in consideration of the response that the actual rotational angular velocity ωr should follow and the total inertia Jm, and the coefficient calculator 23c. Τm * multiplied by {1 ÷ (Pm × φf)} is output as the second q-axis current command iqs2 *, so even when the angular velocity command changes near zero speed or when the load inertia is large There is an effect that the angular velocity command can be followed by the response ωsc (rad / s) that the rotational angular velocity should follow.

  Further, in the fourth embodiment, even when the AC rotating machine is a synchronous machine, when the speed is close to zero speed, the switching signal calculator 20c outputs a TRUE switching signal SW1, and the speed estimation means 5c performs the first estimation. Since the angular velocity ^ ωr1 is replaced with the second estimated angular velocity ^ ωr2 input from the command calculation means 6c, the actual rotation even if the actual rotational angular velocity and the angular velocity command do not coincide immediately after the switching signal SW1 is switched. The angular velocity coincides with the second estimated angular velocity ^ ωr2. Therefore, even when the angular velocity command value changes suddenly and deviates from the vicinity of the zero speed, an effect that the AC rotating machine (synchronous machine) 1c can be driven without switching shock can be obtained.

  As described above, the control device for an AC rotating machine according to the present invention can perform stable speed estimation even in the vicinity of zero speed, and is therefore suitable for applications that require variable speed control of the AC rotating machine in a low speed range.

It is a figure which shows the structure of the control apparatus of the AC rotary machine which concerns on Embodiment 1 of this invention. It is a figure which shows the structure of the command calculating means 6 in the control apparatus of the AC rotary machine which concerns on Embodiment 1 of this invention. It is a figure which shows the structure of the switching signal calculator 20 in the instruction | command calculating means 6 which concerns on Embodiment 1 of this invention. It is a waveform which shows the internal variable in the control apparatus of the AC rotary machine which concerns on Embodiment 1 of this invention. It is a waveform which shows the internal variable of the control apparatus of the AC rotary machine which concerns on Embodiment 1 of this invention, and actual rotational angular velocity. It is a waveform which shows the internal variable of the control apparatus of the AC rotary machine which concerns on Embodiment 1 of this invention, and actual rotational angular velocity. It is a waveform which shows the internal variable of the control apparatus of the AC rotary machine which concerns on Embodiment 1 of this invention, and actual rotational angular velocity. It is a figure which shows the structure of the command calculating means 6a in the control apparatus of the AC rotary machine which concerns on Embodiment 2 of this invention. It is a figure which shows the structure of the switching signal calculator 20a in the command calculating means 6a which concerns on Embodiment 2 of this invention. It is a figure which shows the structure of the control apparatus of the AC rotary machine which concerns on Embodiment 3 of this invention. It is a figure which shows the structure of the instruction | command calculating means 6b in the control apparatus of the AC rotary machine which concerns on Embodiment 3 of this invention. It is a figure which shows the structure of the control apparatus of the alternating current rotary machine which concerns on Embodiment 4 of this invention. It is a figure which shows the structure of the command calculating means 6c in the control apparatus of the alternating current rotating machine which concerns on Embodiment 4 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 AC rotary machine (induction machine), 1c AC rotary machine (synchronous machine), 2 Current detector, 3 Power converter, 4 Coordinate converter, 5, 5c Speed estimation means, 6, 6a, 6b, 6c Command calculation means , 7 Magnetic flux controller, 8 Control means, 9 Current controller, 10 Integrator, 11 Coordinate converter, 20, 20a, 20c Switching signal calculator, 21 Speed response calculator, 22 Torque command calculator, 23, 23c Coefficient Calculator, 24 angular frequency calculator, 25 subtractor, 26 speed controller, 27, 27c switcher, 30 limiter, 31 adder, 32 filter, 33 determiner, 34 determiner, 35 AND operator

Claims (3)

A power converter for applying a voltage to the AC rotating machine;
A current detector for detecting the current of the AC rotating machine;
A speed estimation means for outputting a first angular speed and a first angular frequency as a rotational angular speed of the AC rotating machine based on a current detected from the current detector and a voltage applied by the power converter;
A command calculation means for calculating a deviation angular velocity from a deviation between the angular velocity command and the first estimated angular velocity, and outputting a torque current command and a power supply angular frequency,
The control device for an AC rotating machine, wherein the command calculation means selects a torque current command to be output and a power source angular frequency based on a value limiting the range of the deviation angular velocity and the first estimated angular velocity. . The command calculation means calculates a first torque current command based on the deviation angular velocity, calculates a second estimated angular velocity from a preset speed control response value and the angular velocity command, and also calculates the second estimated angular velocity. The second torque current command is calculated on the basis of the value, and the torque current command to be output is determined based on the value obtained by limiting the range of the deviation angular velocity and the first estimated angular velocity. 2. The AC rotating machine according to claim 1, wherein at least one of the torque current commands is selected and at the same time, either the first angular frequency or the second angular frequency is selected as the power supply angular frequency to be output. Control device. The command calculation means outputs a second estimated angular speed to the speed estimation means and outputs a switching signal to the speed estimation means based on a value obtained by limiting the range of the deviation angular speed and the first estimated angular speed. The speed estimating means is configured to input the first estimated angular speed from the command calculating means while the command calculating means selects the second angular frequency based on the switching signal. The control device for an AC rotating machine according to claim 2, wherein

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