JP2000037098A - Power conversion apparatus using speed sensor-less vector control - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the capacity of a three-phase inverter. SOLUTION: A vector control means of controlling a three-phase inverter 1 on the rotational coordination system of d-q axis is constituted of a current command computing means 5 for computing the current command of torque-axis and magnetic flux-axis from a magnetic flux torque command; a voltage command computing means 6 for computing the voltage command of d-axis and q-axis from at least a torque-axis and magnetic flux axis current command; a coordinate converting means 7 for computing the magnitude of the voltage command comprising d-axis and q-axis voltage commands from the voltage commands of d-axis and q-axis and the angle to the magnetic flux axis; an output frequency computing means 11 for computing the output frequency of the three-phase inverter 1 from at least one of the current, the current command, and the voltage command of a motor; a gate control means 8 for controlling the gate of the three-phase inverter 1 from the integrated phase of the output frequency of the three-phase inverter 1 and the angle of the voltage command; and a magnetic flux command adjusting means 10 for adjusting the magnetic flux command so that the property of the motor meets the command, from at least one of the voltage command, the magnitude of the voltage command, the current of the motor, and the current command.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power converter using speed sensorless vector control for controlling magnetic flux and torque of an induction motor without using a speed detector. In the case of a constant voltage variable frequency (hereinafter, referred to as CVVF) operation in which the output voltage is constant, the capacity of the three-phase inverter can be reduced by controlling the output voltage while keeping the magnitude of the output voltage fixed at the maximum value. The present invention relates to a power conversion device using speed sensorless vector control.

[0002]

2. Description of the Related Art Conventionally, there are many known examples of power conversion devices to which speed sensorless vector control is applied.

[0003] For example, "" Vector control method for speed and voltage sensorless motor of induction motor ""
An example of speed sensorless vector control for driving an induction motor is disclosed in, for example, "Sensorless Vector Control Inverter", Vol.

FIG. 18 is a block diagram showing a schematic configuration example of a conventional power converter to which this kind of speed sensorless vector control is applied.

In FIG. 18, a three-phase inverter 1 for converting a direct current into an alternating current of an arbitrary frequency, an induction motor 2 connected to and driven by the alternating-current side of the three-phase inverter 1,
A main circuit is constituted by the filter capacitor 3 connected to the DC side of the phase inverter 1 and motor drive control is performed by speed sensorless vector control.

On the other hand, in the speed sensorless vector control, current, voltage, and magnetic flux are controlled as vector quantities. An axis coinciding with the magnetic flux axis is defined as d axis, and an axis (torque axis) orthogonal to the d axis is defined as q. On a dq-axis rotating coordinate system that rotates at the same speed as the rotational angular frequency of the output frequency of the three-phase inverter 1 without using a speed detector.
Is controlled.

FIG. 20 is a conceptual diagram showing the relationship between the coordinate systems.

In FIG. 20, the ab axis orthogonal coordinate system is a stationary coordinate system. The dq-axis orthogonal coordinate system is a rotating coordinate system and has a phase difference of θab with respect to the ab-axis stationary coordinate system. Further, the output voltage V has a phase difference θ from the d-axis.
It is assumed to be output at the position of v. The uvw axis is
These axes have a phase difference of 120 deg on the stationary coordinate system, and the a-axis and the u-axis coincide.

There are various types of speed sensorless vector control. Here, the control is performed such that the secondary magnetic flux of the induction motor 2 and the d-axis coincide with each other. Therefore,
The description of the magnetic flux in the following description indicates the secondary magnetic flux.

The vector control unit includes a current detector 4, a current command calculation unit 5, a voltage command calculation unit 6, and a coordinate conversion unit 7.
, A gate control unit 8, an integrating unit 9, and an output frequency calculating unit 11.

That is, the current detector 4 detects the phase currents Iu and Iw flowing through the induction motor 2.

In the current command calculation unit 5, a magnetic flux command φ
^* And the torque command Tm ^* as inputs, for example, the magnetic flux axis (d-axis) current command Id ^* and the torque axis (q-axis) by the following equation.
The current command Iq ^* is calculated.

[0013]

(Equation 1)

Where M: mutual inductance, L2:
Secondary inductance.

In the voltage command calculator 6, the magnetic flux axis (d
Axis) current command Id ^* and torque axis (q axis) current command Iq ^*
, And the d-axis voltage command Vd
^* And the q-axis voltage command Vq ^* are calculated.

[0016]

(Equation 2)

Here, R1: primary resistance, L1: primary inductance, σL1: leakage inductance (= L1 ×
(1− (M × M / L1 / L2))), ωi: inverter output frequency.

In the coordinate conversion unit 7, the d-axis voltage command Vd ^* and the q-axis voltage command Vq ^* , which are the outputs from the voltage command calculation unit 6, are input. V | and the phase angle θv from the d-axis are calculated.

[0019]

(Equation 3)

In the gate control unit 8, the coordinate conversion unit 7
The magnitude of the voltage command | V | output from the inverter, the phase angle θv from the d-axis of the voltage command, and the d-axis of the rotary coordinate system output from the integration unit 9 that integrates the output frequency ωi of the three-phase inverter 1. A gate signal is generated based on the phase angle θab from the stationary coordinate system a-axis.

For example, in the case of the triangular wave comparison PWM control method, the magnitude | V | of the voltage command, the phase angle θv of the voltage command from the d axis, and the phase of the d axis of the rotating coordinate system from the a axis of the stationary coordinate system. Based on the angle θab, the U-phase voltage command Vu ^* , the V-phase voltage command Vv ^*, and the W-phase voltage command Vw are obtained by the following equation, for example.
^* And

[0022]

(Equation 4)

The U-phase voltage command Vu ^* , the V-phase voltage command Vv ^*, and the W-phase voltage command Vw ^* are compared with a triangular wave, and the switching elements of the three-phase inverter 1 are turned on / off according to their magnitudes. To create a signal.

In the above method, the magnitude of the output voltage | V |
The magnitude and phase of the output voltage can be arbitrarily controlled based on the output voltage and the phase θv of the output voltage from the d-axis.

The output frequency calculator 11 outputs the d-axis voltage command Vd ^* and the q-axis voltage command Vq ^* output from the voltage command calculator 6 and the output from the current detector 4 for detecting the current of the induction motor 2. The output frequency ωi of the three-phase inverter 1 is calculated based on the phase currents Iu and Iw, and the magnetic flux axis current command Id ^* and the torque axis current command Iq ^* output from the current command calculation unit 5.

FIG. 19 is a block diagram showing an example of the configuration of the output frequency calculator 11.

In FIG. 19, the output frequency calculator 11
Is composed of an induced voltage calculating unit 21, a divider 32, a proportional-integral controller 33, and an adder 31.

The induced voltage calculator 21 calculates the d-axis induced voltage Ed and the q-axis induced voltage Eq by, for example, the following equation.

[0029]

(Equation 5)

[0030]

(Equation 6)

Where s is a Laplace operator.

In the divider 32, the induced voltage calculator 2
The output frequency reference ωiref is calculated by dividing the q-axis induced voltage Eq calculated by 1 by the magnetic flux command φ ^* .

The proportional-integral controller 33 receives the d-axis induced voltage Ed calculated by the induced voltage calculator 21 and calculates a correction amount Δωi to the output frequency ωi of the three-phase inverter 1 by the following equation, for example. .

[0034]

(Equation 7)

Where Kp: proportional gain, Ki: integral gain.

The output frequency correction amount Δωi is added to the output frequency reference ωiref by the adder 31 to obtain the output frequency ωi.
Becomes

In the configuration shown in FIG. 19, the output frequency reference ωiref calculated based on the q-axis induced voltage Eq is corrected based on the d-axis induced voltage Ed.

When the vector control is established, a vector diagram in a steady state is, for example, as shown in FIG. In this case, the d-axis and the magnetic flux axis coincide, and no d-axis induced voltage Ed is generated.

When vector control does not hold,
That is, a vector diagram in the case where the axis shift occurs is as shown in FIG. 22, for example. Due to the axis deviation, the magnetic flux axis and d
If the axes do not match, the induced voltage is orthogonal to the magnetic flux, and a d-axis induced voltage Ed is generated. Therefore, the output frequency ωi of the three-phase inverter 1 is determined based on the d-axis induced voltage Ed.
Is corrected to compensate for the axis deviation, and the magnetic flux axis and d
It is possible to match the axis.

In the integrating section 9, the output frequency calculating section 1
1, the output frequency ωi thus calculated is input, the output frequency ωi is integrated, and the integrated value is output. The output of the integration unit 9 is the rotation phase angle θab from the stationary coordinate system a axis to the rotating coordinate system d axis.

[0041]

By the way, in the above-described conventional power conversion device to which the speed sensorless vector control is applied, in order to control the torque of the induction motor 2, the magnitude, phase and frequency of the output voltage are controlled. Must be variable.

However, in order to reduce the capacity of the three-phase inverter 1, it is essential to make the most of the output voltage. In the speed sensorless vector control, to allow the output voltage to have a variable size, the three-phase inverter 1
This leads to an increase in capacity, which is not preferable.

An object of the present invention is to make it possible to control the three-phase inverter while keeping the magnitude of the output voltage fixed at the maximum value even when the three-phase inverter performs the CVVF operation in which the magnitude of the output voltage is constant. An object of the present invention is to provide a power converter using speed sensorless vector control capable of reducing the capacity.

[0044]

According to a first aspect of the present invention, there is provided a three-phase inverter for converting a direct current to an alternating current having an arbitrary frequency, and a three-phase inverter connected to the direct-current side of the three-phase inverter. A main circuit is composed of the filter capacitor and an electric motor connected to and driven on the AC side of the three-phase inverter. An axis coinciding with the magnetic flux axis is defined as d-axis, and an axis (torque axis) orthogonal to the d-axis is defined as d-axis. In a power converter configured with vector control means for controlling a three-phase inverter without using a speed detector on a dq-axis rotating coordinate system having a q axis, a magnetic flux command and a torque Current command calculating means for calculating a q-axis current command, which is a torque axis current command, and a d-axis current command, which is a magnetic flux axis current command, based on the current command, and a torque calculated by at least the current command calculating means. A voltage command calculating means for receiving a h-axis current command and a magnetic flux axis current command and calculating a d-axis voltage command and a q-axis voltage command based on the input, and a d-axis voltage command calculated by the voltage command calculating means And a q-axis voltage command, coordinate conversion means for calculating the magnitude of the voltage command consisting of the d-axis voltage command and the q-axis voltage command and the angle of the voltage command with respect to the magnetic flux axis, and detecting the current flowing through the motor. A three-phase current based on at least one of the current of the motor detected by the current detector, the current command calculated by the current command calculator, and the voltage command calculated by the voltage command calculator. An output frequency calculating means for calculating an output frequency of the inverter; an output frequency of the three-phase inverter calculated by the output frequency calculating means; Integrating means for integrating the output frequency to calculate the phase; gate control means for controlling the gate of the three-phase inverter based on the phase calculated by the integrating means and the angle of the voltage command calculated by the coordinate conversion means; At least one of the voltage command calculated by the voltage command calculation means, the magnitude of the voltage command calculated by the coordinate conversion means, the current of the motor detected by the current detection means, and the current command calculated by the current command calculation means. And a magnetic flux command correcting means for correcting the magnetic flux command so that the state quantity of the electric motor matches the corresponding command.

Therefore, in the power converter using the speed sensorless vector control according to the first aspect of the present invention, when the three-phase inverter performs the CVVF operation, the magnetic flux is determined based on the difference between the state quantity of the motor and each corresponding command. By correcting the command, each state quantity of the electric motor matches the corresponding command, and the output torque of the three-phase inverter can follow the command. Operation is possible even in the one-pulse mode, and the voltage of the three-phase inverter can be used to the maximum.

According to the second aspect of the present invention, the first aspect is provided.
In the power conversion device using the speed sensorless vector control according to the invention, the magnetic flux command correction means includes a voltage command calculated by the voltage command calculation means, a voltage command calculated by the coordinate conversion means, and a current detection means. A magnetic flux correction amount calculating means for calculating a magnetic flux correction amount based on at least one of the detected electric current of the motor and a current command calculated by the current command calculating means, and a magnetic flux calculated by the magnetic flux correction amount calculating means And an adder for adding the correction amount and the magnetic flux command.

Therefore, in the power converter using the speed sensorless vector control according to the second aspect of the present invention, when the three-phase inverter performs the CVVF operation, the magnetic flux is determined based on the difference between each state quantity of the motor and the corresponding command. By compensating the magnetic flux command by calculating the correction amount and adding the magnetic flux correction amount to the magnetic flux command, the state quantity of the electric motor and each corresponding command match, and the output torque of the three-phase inverter is used as the command. Can be followed. Operation is possible even in the one-pulse mode, and the voltage of the three-phase inverter can be used to the maximum.

According to a third aspect of the present invention, in the power converter using the speed sensorless vector control according to the second aspect of the present invention, the magnetic flux correction amount calculating means may include:
Output voltage length calculating means for calculating the voltage length indicating the magnitude of the output voltage of the phase inverter; and the magnitude of the voltage command calculated by the coordinate conversion means from the magnitude of the output voltage calculated by the output voltage length calculating means. A subtraction means for calculating a deviation by subtraction, and a second magnetic flux correction amount calculation means for calculating a magnetic flux correction amount based on the voltage deviation calculated by the subtraction means.

Therefore, in the power converter using the speed sensorless vector control according to the third aspect of the present invention, when the three-phase inverter performs the CVVF operation, the magnitude | V of the output voltage actually output from the three-phase inverter Based on the difference between | ^* and the magnitude of the output voltage | V | based on the voltage command, the magnetic flux correction amount is calculated so that this difference becomes zero, and this magnetic flux correction amount is added to the magnetic flux command to obtain the magnetic flux. By correcting the command, the actual voltage length applied to the motor and the voltage command length output from the three-phase inverter coincide with each other, so that each state quantity of the motor matches each corresponding command, and the three-phase inverter The output torque can follow the command. Operable even in one-pulse mode.
The voltage of the phase inverter can be used to the maximum.

According to a fourth aspect of the present invention, in the power converter using the speed sensorless vector control according to the third aspect of the present invention, the output voltage length calculating means detects a DC link voltage applied to a filter capacitor. And a second output voltage length calculating means for calculating an output voltage length based on the DC link voltage detected by the voltage detecting means.

Therefore, in the power converter using the speed sensorless vector control according to the fourth aspect of the present invention, when the three-phase inverter performs the CVVF operation, the magnitude of the actual output voltage output from the three-phase inverter and the command Based on the deviation from the magnitude of the output voltage of the motor, the magnetic flux correction amount is calculated so that this deviation becomes zero, and the magnetic flux command is corrected by adding the magnetic flux correction value to the magnetic flux command. When the actual voltage length matches the voltage command length, each state quantity of the electric motor matches each corresponding command, and the output torque can follow the command. Operation is possible even in the one-pulse mode, and the voltage of the three-phase inverter can be used to the maximum.

In particular, even when the DC link voltage fluctuates, by calculating the magnitude of the output voltage corresponding to the DC link voltage, the output torque can be used as the command regardless of the DC link voltage fluctuation. Can be followed.

On the other hand, in the invention of claim 5, the above-mentioned claim 2
In the power converter using the speed sensorless vector control according to the invention, the magnetic flux correction amount calculating means includes a voltage command calculated by the voltage command calculating means, a current of the motor detected by the current detecting means, and a current command calculating means. A magnetic flux length calculating means for calculating a magnetic flux length indicating the magnitude of the magnetic flux based on at least one of the current commands calculated by the magnetic flux command calculating means, and a magnetic flux command correcting means based on the magnitude of the magnetic flux calculated by the magnetic flux length calculating means And a second magnetic flux correction amount calculating means for calculating a magnetic flux correction amount based on the magnetic flux deviation calculated by the subtraction means.

Therefore, in the power converter using the speed sensorless vector control according to the fifth aspect of the present invention, when the three-phase inverter performs the CVVF operation, based on the deviation between the estimated magnetic flux magnitude and the magnetic flux command. The magnetic flux correction amount is calculated so that this deviation becomes zero. In the case of the CVVF operation, if the magnetic flux command does not match the actual magnetic flux amount, the command value of the output voltage does not match the actual output voltage. By matching the actual magnetic flux length applied to the motor with the magnetic flux command length,
Each state quantity of the motor matches each corresponding command, and the output torque of the three-phase inverter can follow the command. Operation is possible even in the one-pulse mode, and the voltage of the three-phase inverter can be used to the maximum.

According to the sixth aspect of the present invention, in the second aspect,
In the power converter using the speed sensorless vector control according to the invention, the magnetic flux correction amount calculating means includes a voltage command calculated by the voltage command calculating means, a current of the motor detected by the current detecting means, and a current command calculating means. A d-axis magnetic flux calculating means for calculating a d-axis magnetic flux on a dq-axis rotating coordinate system based on at least one of the current commands calculated by Subtraction means for calculating a deviation by subtracting the magnetic flux command corrected by the magnetic flux command correction means from the magnitude, and a second magnetic flux correction quantity for calculating a magnetic flux correction quantity based on the deviation of the magnetic flux calculated by the subtraction means Computing means.

Therefore, in the power converter using the speed sensorless vector control according to the sixth aspect of the present invention, the magnitude of the actual d-axis magnetic flux generated in the motor and the corrected magnetic flux when the three-phase inverter performs the CVVF operation. The magnetic flux correction amount is calculated based on the deviation from the command so that the deviation becomes zero. In the vector control, control is performed so that the d-axis and the magnetic flux axis coincide, that is, the q-axis magnetic flux is zero. CV
In the case of the VF operation, if the d-axis magnetic flux actually generated in the motor does not match the magnetic flux command, the voltage command does not match the actual output voltage. By estimating and calculating the d-axis magnetic flux of the motor and calculating the magnetic flux command amount according to the deviation from the magnetic flux command, each state quantity of the motor matches each corresponding command, and the output torque of the three-phase inverter is adjusted by the command. Can be followed. 1
It can operate even in the pulse mode, and can make maximum use of the voltage of the three-phase inverter.

According to a seventh aspect of the present invention, in the power conversion device using the speed sensorless vector control according to the second aspect of the present invention, the magnetic flux correction amount calculating means includes a voltage command calculated by a voltage command calculating means. And a d-axis induced voltage and a q-axis induced voltage on the dq-axis rotating coordinate system based on at least one of the current of the motor detected by the current detecting means and the current command calculated by the current command calculating means. An induced voltage calculating means for calculating, based on the d-axis induced voltage and the q-axis induced voltage calculated by the induced voltage calculating means, an induced voltage length calculating means for calculating an induced voltage length indicating the magnitude of the induced voltage; Calculating an induced voltage reference based on the magnetic flux command corrected by the magnetic flux command correcting means and the output frequency of the three-phase inverter calculated by the output frequency calculating means. Induced voltage reference calculation means, subtraction means for calculating a deviation by subtracting the induced voltage reference calculated by the induced voltage reference calculation means from the induced voltage length calculated by the induced voltage length calculation means, and calculation by the subtraction means. And a second magnetic flux correction amount calculating means for calculating a magnetic flux correction amount based on the deviation of the induced voltage.

Therefore, in the power converter using the speed sensorless vector control according to the seventh aspect of the present invention, when the three-phase inverter performs the CVVF operation, the deviation between the magnitude of the estimated induced voltage and the induced voltage reference is calculated. Based on this, the magnetic flux correction amount is calculated so that this deviation becomes zero. CVV
In the case of the F operation, if the magnetic flux command does not match the actual amount of magnetic flux, the induced voltage reference does not match the magnitude of the actual induced voltage. By calculating a magnetic flux correction amount based on a deviation between the estimated and calculated induced voltage and the induced voltage reference, each state quantity of the motor matches each corresponding command, and the output torque of the three-phase inverter follows the command. Can be done. Operation is possible even in the one-pulse mode, and the voltage of the three-phase inverter can be used to the maximum.

According to an eighth aspect of the present invention, in the power converter using the speed sensorless vector control according to the second aspect of the present invention, the magnetic flux correction amount calculating means includes a voltage calculated by a voltage command calculating means. A d-axis induced voltage and a q-axis induced voltage on the dq-axis rotating coordinate system based on at least one of the command and the current of the motor detected by the current detecting means and the current command calculated by the current command calculating means. Induced voltage calculation means for calculating the induced voltage reference, and induced voltage reference calculation means for calculating the induced voltage reference based on the magnetic flux command corrected by the magnetic flux command correction means and the output frequency of the three-phase inverter calculated by the output frequency calculation means And subtraction of the induced voltage reference calculated by the induced voltage reference calculating means from the q-axis induced voltage calculated by the induced voltage calculating means, and a deviation Subtracting means for calculating, based on the deviation of the calculated induced voltage by subtracting means, and a second magnetic flux correction amount calculating means for calculating a magnetic flux correction amount.

Therefore, in the power converter using the speed sensorless vector control according to the present invention, when the three-phase inverter performs the CVVF operation, the estimated and calculated q is calculated.
Based on the deviation between the magnitude of the shaft induced voltage and the reference of the induced voltage, the magnetic flux correction amount is calculated so that the deviation becomes zero.
When vector control is performed, only the q-axis induced voltage is generated and no d-axis induced voltage is generated in order to make the magnetic flux coincide with the d-axis. When the three-phase inverter performs the CVVF operation, if the magnetic flux command does not match the actual magnetic flux amount, the induced voltage reference does not match the actual q-axis induced voltage. Estimated q
By calculating the magnetic flux correction amount based on the deviation between the shaft induced voltage and the induced voltage reference, each state quantity of the motor matches each corresponding command, and the output torque of the three-phase inverter can follow the command. it can. Operation is possible even in the one-pulse mode, and the voltage of the three-phase inverter can be used to the maximum.

On the other hand, according to the ninth aspect of the present invention, the first aspect of the present invention relates to
In the power conversion device using the speed sensorless vector control according to the invention of the first aspect, in the power conversion device using the speed sensorless vector control according to the first aspect of the invention, the voltage command calculation means is calculated by a current command calculation means. A torque axis current command, a magnetic flux axis current command, and a current of the motor detected by the current detecting means are input, and a d-axis voltage command and a q-axis voltage command are calculated based on the input.

Therefore, in the power converter using the speed sensorless vector control according to the ninth aspect of the invention, in addition to the torque axis current command and the magnetic flux axis current command, the d-axis voltage command and the q-axis By calculating the voltage command, it is possible to suppress overcorrection with respect to magnetic flux correction.

[0063]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(First Embodiment) FIG. 1 is a block diagram showing a schematic configuration example of a power converter using speed sensorless vector control according to the present embodiment, and the same elements as those in FIG. Are shown.

In FIG. 1, a three-phase inverter 1 for converting a direct current to an alternating current of an arbitrary frequency, and the three-phase inverter 1
The main circuit is composed of an induction motor 2 connected to and driven by the AC side of the inverter and a filter capacitor 3 connected to the DC side of the three-phase inverter 1, and performs motor drive control by speed sensorless vector control. ing. In the present embodiment, a case where the induction motor 2 is driven as an electric motor will be described.

On the other hand, in the speed sensorless vector control, current, voltage, and magnetic flux are controlled as vector quantities, an axis coinciding with the magnetic flux axis is defined as d axis, and an axis (torque axis) orthogonal to the d axis is defined as q. On a dq axis rotation coordinate system as an axis,
The three-phase inverter 1 is controlled without using the speed detector.

The vector control unit includes a current detector 4, a current command calculation unit 5, a voltage command calculation unit 6, and a coordinate conversion unit 7.
, A gate control unit 8, an integration unit 9, and a magnetic flux command correction unit 1.
0 and an output frequency calculator 11.

The current detector 4 detects the phase currents Iu and Iw flowing through the induction motor 2.

The current command calculation unit 5 receives a flux command φ ^* cmp and a torque command Tm ^* after correction, which will be described later, and based on the inputs, a q-axis current command Iq ^* which is a torque axis current command and a magnetic flux command A d-axis current command Id ^* , which is a shaft current command, is calculated.

The voltage command calculation unit 6 receives the torque axis current command Iq ^* and the magnetic flux axis current command Id ^* calculated by the current command calculation unit 5 as inputs, and based on these inputs, d-axis voltage commands Vd ^* and q The shaft voltage command Vq ^* is calculated.

The output frequency calculator 11 calculates the phase currents Iu and Iw of the induction motor 2 detected by the current detector 4 and the current commands Id ^* and Iq calculated by the current command calculator 5.
^*, And the voltage command Vd calculated by the voltage command calculation unit 6
The output frequency ωi of the three-phase inverter 1 is calculated based on at least one of ^* , Vq ^* .

The integrator 9 receives the output frequency ωi of the three-phase inverter 1 calculated by the output frequency calculator 11 as an input, and the input output frequency ωi of the three-phase inverter 1
To calculate the phase θab.

The coordinate converter 7 receives the d-axis voltage command Vd ^* and the q-axis voltage command Vq ^* calculated by the voltage command calculator 6 as inputs, and based on the inputs, the magnitude | V of the voltage command.
And the phase angle θv from the d-axis is calculated.

The gate control unit 8 determines the phase angle θv of the voltage command calculated by the coordinate conversion unit 7 from the d-axis and the integration unit 9
The gate of the three-phase inverter 1 is controlled based on the phase angle θab of the rotating coordinate system d axis from the stationary coordinate system a axis calculated by

The magnetic flux command correction unit 10 includes a voltage command calculation unit 6
The calculated voltage command Vd by ^*, Vq ^* and the magnitude of the voltage command calculated by the coordinate converter 7 | V | and the detected induction motor 2 of the phase current Iu by the current detector 4,
Based on at least one of Iw, the magnetic flux command φ ^* is corrected so that the state quantity such as current, voltage, and magnetic flux of the induction motor 2 matches the corresponding command, and the corrected magnetic flux command φ ^* cmp is calculated. I do.

Next, the operation of the power converter using the speed sensorless vector control of the present embodiment configured as described above will be described.

In FIG. 1, a magnetic flux command φ ^* is input to a magnetic flux command correcting unit 10, which corrects the magnetic flux command as described later in detail, and outputs a corrected magnetic flux command φ ^* cmp.

The corrected magnetic flux command φ ^* cmp and the torque command Tm ^* are input to the current command calculating unit 5. For example, the magnetic flux axis (d-axis) current command Id ^* and the torque axis (q
(Axis) current command Iq ^* is calculated.

[0079]

(Equation 8)

Where M: mutual inductance, L2:
Secondary inductance.

The magnetic flux axis (d-axis) current command Id ^* and the torque axis (q-axis) current command Iq ^* are input to the voltage command calculator 6, and the d-axis voltage command Vd ^* and the q
The shaft voltage command Vq ^* is calculated.

[0082]

(Equation 9)

Where R1: primary resistance, L1: primary inductance, σL1: leakage inductance (= L1 ×
(1−M × M / L1 / L2))), ωi: inverter output frequency.

The coordinate converter 7 has a d-axis voltage command Vd ^* and a q-axis voltage command Vq ^* , which are the outputs from the voltage command calculator 6 ^.
Is input, and the magnitude of the voltage command | V
And the phase angle θv from the d-axis are calculated.

[0085]

(Equation 10)

The gate control unit 8 calculates the phase angle θv of the voltage command output from the coordinate conversion unit 7 from the d-axis and the phase angle θv of the rotation coordinate system d-axis output from the integration unit 9 from the stationary coordinate system a-axis. The gate signal is generated based on the phase angle θab.

For example, the operation in the one-pulse mode in which the three-phase inverter 1 can output the maximum voltage will be briefly described.

The one-pulse mode is an operation mode in which each phase of the three-phase inverter 1 turns on and off by 180 degrees in one output cycle. From the phase angle θv of the voltage command input to the gate control unit 8 from the d-axis and the phase angle θab of the rotating coordinate system d-axis from the stationary coordinate system a-axis, the phases θuu, θvv, θww is determined by the following equation, for example.

[0089]

[Equation 11]

Then, based on the phases θuu, θvv, θww of the respective phases of the three-phase inverter 1, a gate signal for obtaining an output such as the following equation is generated.

[0091]

(Equation 12)

Vdc: DC link voltage.

In the one-pulse mode, the magnitude of the output voltage of three-phase inverter 1 is constant, and only the phase can be controlled. It is a feature that the magnitude of the output voltage of the three-phase inverter 1 is the maximum value that the three-phase inverter 1 can output.

When the three-phase inverter 1 performs the CVVF operation represented by the one-pulse mode, the magnitude of the output voltage cannot be controlled, and only the phase and frequency of the output voltage can be controlled.

The magnetic flux command correction unit 10 outputs the d-axis voltage command Vd ^* and the q-axis voltage command Vq ^* output from the voltage command calculation unit 6 and the magnitude | of the voltage command output from the coordinate conversion unit 7. Based on V | and the phase currents Iu and Iw of the induction motor 2 detected by the current detector 4, a difference between the actual state quantity of the induction motor 2 and the corresponding command is determined.
The magnetic flux command φ ^* is corrected. Since the voltage of the induction motor 2 is approximately represented by magnetic flux × frequency, the magnitude of the output voltage is corrected by correcting the magnetic flux command φ ^* .

The output frequency calculating section 11 outputs the d-axis voltage command Vd ^* and the q-axis voltage command Vq ^* output from the voltage command calculating section 6 and the magnetic flux axis (d-axis output) output from the current command calculating section 5. ) Current command Id ^* , torque axis (q axis) current command I
q ^*, and each phase current Iu, Iw of the induction motor 2 detected by the current detector 4, based on the three-phase inverter 1
Is calculated.

Here, as shown in FIG. 2, for example, the output frequency calculator 11 includes an output frequency reference amount calculator 27, an output frequency correction amount calculator 28, a multiplier 30, and an adder 3.
And 1.

The output frequency reference amount calculator 27 outputs the d-axis voltage command Vd ^* and the q-axis voltage command Vq ^* output from the voltage command calculator 6 and the magnetic flux axis (d) output from the current command calculator 5. Axis) current command Id ^* , torque axis (q-axis) current command Iq ^* , induction motor 2 detected by current detector 4
The output frequency reference amount is calculated based on at least one of the phase currents Iu and Iw.

The gain K is also input to the multiplier 30. This gain K assumes 0 or 1.

The multiplier 30 multiplies the output frequency reference amount output from the output frequency reference amount calculator 27 by the gain K to output the output frequency reference amount ωiref.

In the output frequency correction amount calculator 28,
The d-axis voltage command V output from the voltage command calculation unit 6
d ^* , q-axis voltage command Vq ^* , magnetic flux axis (d-axis) current command Id ^* output from current command calculation section 5, torque axis (q
Axis) The correction amount Δ to the output frequency reference amount ωiref based on at least one of the current command Iq ^* , each phase current of the induction motor 2 detected by the current detector 4, and Iu and Iw.
ωi is calculated.

The output frequency reference ωiref output from the multiplier 30 and the output frequency correction amount Δωi output from the output frequency correction amount calculator 28 are input to the adder 31. The output frequency reference ωiref And output frequency correction amount Δ
ωi and the output frequency ωi of the three-phase inverter 1
Is calculated.

Thus, the output frequency ωi of the three-phase inverter 1 calculated by the output frequency calculator 11 is
The signal is input to the integration section 9 and the integrated value is output. The output of the integration unit 9 is the rotation phase angle θab from the stationary coordinate system a axis to the rotating coordinate system d axis.

As described above, in the power converter using the speed sensorless vector control according to the present embodiment, when the three-phase inverter 1 performs the CVVF operation, each state quantity such as current, voltage, and magnetic flux of the induction motor 2 is obtained. By correcting the magnetic flux command φ ^* based on the difference from each corresponding command,
Each state quantity of the induction motor 2 matches each command, and the output torque of the three-phase inverter 1 can follow the command. It can operate even in one pulse mode,
The voltage of the three-phase inverter 1 can be used to the maximum.

As described above, even when the three-phase inverter 1 performs the CVVF operation in which the magnitude of the output voltage is constant, control can be performed while the magnitude of the output voltage is fixed at the maximum value. The capacity can be reduced.

(Modification of First Embodiment) In the output frequency calculating section 11 of the first embodiment, when the gain K is 1, the output frequency reference amount ωiref and the output frequency correction amount Δωi And the output frequency ωi is obtained by adding the output frequency ωi. When the gain K = 0, the output frequency reference amount ωiref is not calculated, and the output frequency correction amount Δωi is set to the output frequency ωi. Become.

FIG. 3 is a block diagram showing another example of the configuration of the output frequency calculator 11.

In FIG. 3, the output frequency calculating section 11
It comprises an output frequency reference amount calculator 27, an output frequency correction amount calculator 28, a multiplier 30, and an adder 31.

The output frequency reference amount calculator 27 comprises an induced voltage calculator 21 and a divider 32.

Further, the output frequency correction amount calculating unit 28
It comprises an induced voltage calculator 21 and a proportional-integral controller 33.

The induced voltage calculator 21 calculates the q-axis induced voltage Eq by the following equation, for example.

[0112]

(Equation 13)

In the divider 32, the q-axis induced voltage Eq output from the induced voltage calculator 21 is corrected to the corrected magnetic flux command value φ ^*.
Divide by cmp.

The output from the divider 32 is multiplied by a gain K to obtain an output frequency reference ωiref.

In the output frequency correction amount calculator 28, the d-axis induced voltage Ed calculated by the induced voltage calculator 21 is input to the proportional-integral controller 33.
For example, the output frequency correction amount Δωi is calculated by the following equation.

[0116]

[Equation 14]

Here, Kp: proportional gain, Ki: integral gain.

The output frequency correction amount Δωi is
The adder 31 adds the output frequency reference amount ωiref to the output frequency ωi of the three-phase inverter 1.

In the output frequency calculator 11 shown in FIG.
Assuming that the gain K is 1, the output frequency reference ωiref calculated based on the q-axis induced voltage is changed to the d-axis induced voltage Ed
Is corrected based on

As shown in FIG. 21 described above, when vector control is established, that is, when the d-axis and the magnetic flux axis coincide, no d-axis induced voltage is generated. By correcting the output frequency based on the d-axis induced voltage, the axis deviation is compensated,
It is possible to make the magnetic flux axis coincide with the d axis.

Further, even when the gain K is 0 and the output frequency reference ωiref does not exist, a stable operation in which the axis deviation is compensated can be performed by the action of the integral of the proportional-integral controller 33.

FIG. 4 is a block diagram showing another example of the configuration of the output frequency calculating section 11. In FIG.

In this example, since the gain K is 0, there is no output frequency reference amount calculator.

In FIG. 4, the output frequency calculating section 11
A coordinate system converter 34, a subtractor 35, and a proportional-integral controller 3
And 3.

The coordinate system converter 34 converts each phase current Iu, Iw of the induction motor 2 into currents Id, Iq on the dq axis rotation coordinate system, for example, by the following equation.

Where θab is the phase angle from the a-axis of the stationary coordinate system to the d-axis of the rotating coordinate system.

[0127]

(Equation 15)

The subtracter 35 calculates the deviation ΔIq by subtracting the torque axis (q-axis) current Iq from the torque axis (q-axis) current command Iq ^* .

The proportional-integral controller 33 receives the deviation ΔIq of the torque axis (q-axis) current, and outputs the output frequency ωi of the three-phase inverter 1.

In the output frequency calculator 11 of FIG.
The output frequency ωi of the three-phase inverter 1 is corrected based on the deviation ΔIq of the torque axis (q axis) current.

As shown in FIG. 21, when the vector control is established, the torque axis (q-axis) current command Iq ^*
And the torque axis (q-axis) current Iq match. This deviation ΔIq of the torque axis (q-axis) current is considered to be generated because the output frequency ωi of the three-phase inverter 1 is not appropriately given as vector control.

By correcting and calculating the output frequency ωi of the three-phase inverter 1 based on the deviation ΔIq of the torque axis current, it is possible to make the magnetic flux axis and the d axis, which are the conditions of the vector control, coincide.

(Second Embodiment) FIG. 5 is a block diagram showing a schematic configuration example of a magnetic flux command correction unit 10 in a power converter using speed sensorless vector control according to the present embodiment. The same elements as those described above are denoted by the same reference numerals and description thereof will be omitted, and only different parts will be described here.

That is, as shown in FIG. 5, the magnetic flux command correction unit 10 of the present embodiment includes a magnetic flux correction amount calculator 12
And an adder 13.

The magnetic flux correction amount calculator 12 includes the voltage commands Vd ^* and Vq ^* calculated by the voltage command calculator 6, the magnitude | V | of the voltage command calculated by the coordinate converter 7, the current detector 4, the phase current I of the induction motor 2 detected by the
u, Iw, and at least one of the current commands Iq ^* , Id ^* calculated by the current command calculation unit 5,
Calculate the magnetic flux correction amount φcmp.

[0136] The adder 13 adds the flux correction amount calculator 12 flux correction amount computed by φcmp and the magnetic flux command phi ^*, and outputs the magnetic flux command phi ^* cmp corrected.

Next, the operation of the power converter using the speed sensorless vector control according to the present embodiment configured as described above will be described.

Here, only the operation of the portion different from that of FIG. 1 will be described.

In FIG. 5, a magnetic flux correction amount calculator 12 outputs a d-axis voltage command V
d ^* , q-axis voltage command Vq ^* , magnitude | V | of voltage command output from coordinate conversion unit 7, magnetic flux axis (d-axis) current command Id ^* output from current command calculation unit 5, torque Based on the axis (q-axis) current command Iq ^* and each phase current Iu, Iw of the induction motor 2 detected by the current detector 4, the difference between the actual state quantity of the induction motor 2 and the corresponding command is determined. Then, a magnetic flux correction amount φcmp to the magnetic flux command φ ^* is calculated.

[0140] Then, the magnetic flux correction amount φcmp to this magnetic flux command phi ^* is summed with the flux command phi ^* by the adder 13, the magnetic flux command phi ^* cmp after correction is outputted.

As described above, in the power converter using the speed sensorless vector control of the present embodiment, when the three-phase inverter 1 performs the CVVF operation, each state quantity such as current, voltage, and magnetic flux of the induction motor 2 is obtained. calculating a magnetic flux correction amount φcmp based on the difference between each corresponding command, by correcting the magnetic flux command phi ^* by adding the flux correction amount φcmp the flux command phi ^*, each state quantity of the induction motor 2 And the respective commands match, and the output torque of the three-phase inverter 1 can follow the commands. Operation is possible even in the one-pulse mode, and the voltage of the three-phase inverter 1 can be used to the maximum.

As described above, even when the three-phase inverter 1 performs the CVVF operation in which the magnitude of the output voltage is constant, the control can be performed while the magnitude of the output voltage is fixed at the maximum value. The capacity can be reduced.

(Third Embodiment) FIG. 6 shows a magnetic flux correction amount calculator 1 of a magnetic flux command correction unit 10 in a power converter using speed sensorless vector control according to the present embodiment.
2 is a block diagram showing an example of a schematic configuration of FIG. 2, in which the same elements as those in FIG. 1 and FIG. 5 are denoted by the same reference numerals, and the description thereof will be omitted;

That is, as shown in FIG. 6, the magnetic flux correction amount calculator 12 of the present embodiment includes an output voltage length calculator 15.
, A subtractor 16 and a second magnetic flux correction amount calculator 14.

Output voltage length calculator 15 calculates a voltage length indicating the magnitude | V | ^* of the output voltage of three-phase inverter 1.

The subtractor 16 subtracts the magnitude | V | of the voltage command computed by the coordinate conversion unit 7 from the magnitude | V | ^{* of} the output voltage computed by the output voltage length computing unit 15, The deviation Δ | V | is calculated.

The second magnetic flux correction amount calculator 14 is provided with a subtractor 1
6, the magnetic flux correction amount φcmp is calculated based on the voltage deviation Δ | V |

Next, the operation of the power converter using the speed sensorless vector control of the present embodiment configured as described above will be described.

Here, only the operation of the portions different from those of FIGS. 1 and 5 will be described.

In FIG. 6, the output voltage length calculator 15 calculates the magnitude of the output voltage actually output from the three-phase inverter 1 when the three-phase inverter 1 performs the CVVF operation.

For example, when the three-phase inverter 1 is in the one-pulse mode, the magnitude | V | ^* of the output voltage actually output from the three-phase inverter 1 is uniquely determined from the DC link voltage Vdc by the following equation, for example. .

The output voltage length calculator 15 outputs the output voltage length actually output from the three-phase inverter 1, that is, the magnitude | V | ^{* of the} output voltage.

[0153]

(Equation 16)

The subtractor 16 calculates the actual output voltage magnitude | V | ^* output from the output voltage length calculator 15 from
The magnitude | V | of the output voltage as a command output from the coordinate conversion unit 7 is subtracted.

The output Δ | V | from the subtractor 16 is 3
The difference between the actual value of the magnitude of the output voltage of the phase inverter 1 and the command value is input to the second magnetic flux correction amount calculator 14.

The second magnetic flux correction amount calculator 14 calculates the deviation Δ | V | between the actual value of the magnitude of the output voltage output from the subtractor 16 and the command value, for example, by the following equation: Accordingly, the magnetic flux correction amount φcmp is calculated by the proportional integral control.

[0157]

[Equation 17]

Here, s: Laplace operator, Kp: proportional gain, Ki: integral gain.

That is, when the magnitude | V | ^* of the output voltage actually output from the three-phase inverter 1 is larger than the magnitude | V | of the output voltage as the command (Δ | V |>)
0), the gains Kp and Kp are set so as to increase the magnetic flux command φ ^* , that is, to output a positive magnetic flux correction amount φcmp.
Ki is set.

Since the magnitude | V | of the output voltage is approximately proportional to the magnetic flux command φ ^* in the high-speed rotation region, the magnitude of the output voltage as the command is given by increasing the corrected magnetic flux command φ ^* cmp. V | can be increased.

As described above, in the power converter using the speed sensorless vector control of the present embodiment, when the three-phase inverter 1 performs the CVVF operation, the magnitude of the output voltage actually output from the three-phase inverter 1 | V | ^* and the magnitude of the output voltage based on the voltage command | V |
, The magnetic flux correction amount φcmp is calculated so that the deviation Δ | V | becomes zero, and the magnetic flux command φ ^* is corrected by adding the magnetic flux correction amount φcmp to the magnetic flux command φ ^* . When the magnitude of the voltage output from the three-phase inverter 1 and applied to the induction motor 2 matches the magnitude of the voltage command, each state quantity of the induction motor 2 and each command match, and the three-phase inverter 1 Can follow the command. Operation is possible even in the one-pulse mode, and the voltage of the three-phase inverter 1 can be used to the maximum.

As described above, even when the three-phase inverter 1 performs the CVVF operation in which the magnitude of the output voltage is constant, control can be performed while the magnitude of the output voltage is fixed at the maximum value. The capacity can be reduced.

(Fourth Embodiment) FIG. 7 shows a magnetic flux correction amount calculator 1 of a magnetic flux command correction unit 10 in a power converter using speed sensorless vector control according to the present embodiment.
2 is a block diagram showing an example of a schematic configuration of FIG. 2, in which the same elements as those in FIG. 1 and FIG. 5 are denoted by the same reference numerals, and the description thereof will be omitted;

That is, as shown in FIG. 7, the magnetic flux correction amount calculator 12 of the present embodiment includes a DC voltage detector 17
It comprises a second output voltage length calculator 18, a subtractor 16, and a second magnetic flux correction amount calculator 14.

DC voltage detector 17 detects DC link voltage Vdc applied to filter capacitor 3.

The second output voltage length calculator 18 calculates a voltage length indicating the magnitude | V | ^* of the output voltage of the three-phase inverter 1 based on the DC link voltage Vdc detected by the voltage detector 17. I do.

The subtractor 16 is the second output voltage length calculator 1
8, the magnitude of the voltage command computed by the coordinate conversion unit 7 from the magnitude | V | ^{* of} the output voltage computed by
Is subtracted to calculate the deviation Δ | V |.

The second magnetic flux correction amount calculator 14 has a subtractor 1
6, the magnetic flux correction amount φcmp is calculated based on the voltage deviation Δ | V |

Next, the operation of the power converter using the speed sensorless vector control of the present embodiment configured as described above will be described.

Here, only the operation of the portions different from those of FIGS. 1 and 5 will be described.

In FIG. 7, in the DC voltage detector 17,
The DC link voltage Vdc applied to the filter capacitor 3 connected to the DC side of the three-phase inverter 1 is detected, and the detected DC link voltage Vdc is input to the second output voltage length calculator 18.

The second output voltage length calculator 18 calculates the magnitude | V | ^{* of the} output voltage actually output from the three-phase inverter 1 when the three-phase inverter 1 performs the CVVF operation.

For example, when the three-phase inverter 1 is in the one-pulse mode, the magnitude | V | ^* of the output voltage actually output from the three-phase inverter 1 is calculated according to the DC link voltage Vdc by the following equation, for example. Is done.

[0174]

(Equation 18)

In the subtracter 16, the magnitude | V | ^* of the actual output voltage output from the second output voltage length calculator 18 ^.
Is subtracted from the output voltage magnitude | V | as a command output from the coordinate conversion unit 7.

The output Δ | V | from the subtractor 16 is 3
The difference between the magnitude of the actual output voltage output from the phase inverter 1 and the magnitude of the output voltage as a command is input to the second magnetic flux correction amount calculator 14.

The second magnetic flux correction amount calculator 14 calculates the deviation Δ | V | between the actual value of the magnitude of the output voltage output from the subtractor 16 and the command value, for example, by the following equation: Thus, the magnetic flux correction amount φcmp is calculated by proportional control.

[0178]

[Equation 19]

S: Laplace operator, Kp: proportional gain, Ki: integral gain.

That is, when the magnitude | V | ^* of the output voltage actually output from the three-phase inverter 1 is larger than the magnitude | V | of the output voltage as the command (Δ | V |>)
0), the gains Kp and Kp are set so as to increase the magnetic flux command φ ^* , that is, to output a positive magnetic flux correction amount φcmp.
Ki is set.

Since the magnitude | V | of the output voltage is substantially proportional to the magnetic flux command φ ^* in the high-speed rotation region, the magnitude of the output voltage as the command is given by increasing the corrected magnetic flux command φ ^* cmp. V | can be increased.

As described above, in the power conversion device using the speed sensorless vector control according to the present embodiment, when the three-phase inverter 1 performs the CVVF operation, the magnitude of the output voltage actually output from the three-phase inverter 1 | V | ^* and the magnitude of the output voltage based on the voltage command | V |
, The magnetic flux correction amount φcmp is calculated so that the deviation Δ | V | becomes zero, and the magnetic flux command φ ^* is corrected by adding the magnetic flux correction amount φcmp to the magnetic flux command φ ^*. I have.

Therefore, the output from the three-phase inverter 1 is
When the actual voltage length applied to the induction motor 2 and the voltage command length match, each state quantity of the induction motor 2 matches each command, and the output torque of the three-phase inverter 1 follows the command. Can be. Operation is possible even in the one-pulse mode, and the voltage of the three-phase inverter 1 can be used to the maximum.

In particular, even when the DC link voltage Vdc fluctuates, by calculating the magnitude of the output voltage according to the DC link voltage Vdc, the DC link voltage Vdc is calculated.
, The output torque of the three-phase inverter 1 can follow the command.

As described above, even in the case where the three-phase inverter 1 performs the CVVF operation in which the magnitude of the output voltage is constant, control can be performed while the magnitude of the output voltage is fixed at the maximum value. The capacity can be reduced, and furthermore, it is possible to cope with fluctuations in the output voltage of the three-phase inverter 1.

(Fifth Embodiment) FIG. 8 shows a magnetic flux correction amount calculator 1 of a magnetic flux command correction unit 10 in a power converter using speed sensorless vector control according to the present embodiment.
2 is a block diagram showing an example of a schematic configuration of FIG. 2, in which the same elements as those in FIG. 1 and FIG. 5 are denoted by the same reference numerals, and the description thereof will be omitted;

That is, as shown in FIG. 8, the magnetic flux correction amount calculator 12 of the present embodiment comprises a magnetic flux length calculator 19, a subtractor 16, and a second magnetic flux correction amount calculator 14. ing.

The magnetic flux length calculator 19 calculates the voltage commands Vd ^* and Vq ^* calculated by the voltage command calculator 6 and the phase current I of the induction motor 2 detected by the current detector 4.
u, Iw, and the magnetic flux length indicating the magnitude | φ | of the magnetic flux based on at least one of the torque axis current command Iq ^* and the magnetic flux axis current command Id ^* calculated by the current command calculator 5. Calculate.

The subtractor 16 calculates the magnitude of the magnetic flux | φ |
The deviation Δ | φ | is calculated by subtracting the magnetic flux command φ ^* cmp corrected by 0.

The second magnetic flux correction amount calculator 14 is provided with a subtractor 1
6, the magnetic flux correction amount φcmp is calculated based on the magnetic flux deviation Δ | φ |

Next, the operation of the power converter using the speed sensorless vector control of the present embodiment configured as described above will be described.

Here, only the operation of the portions different from those of FIGS. 1 and 5 will be described.

In FIG. 8, the magnetic flux length calculator 19 calculates the magnetic flux by the following equation, for example.

[0194]

(Equation 20)

[0195]

(Equation 21)

[0196]

(Equation 22)

In this case, there are many methods for estimating the magnetic flux other than the above-mentioned calculation, and the method is not limited here.

The subtractor 16 subtracts the corrected magnetic flux command φ ^* cmp from the magnetic flux magnitude | φ | output from the magnetic flux length calculator 19.

The output Δ | φ | from the subtractor 16 represents the deviation between the magnitude of the estimated magnetic flux and the command value.
It is input to the second magnetic flux correction amount calculator 14.

In the second magnetic flux correction amount calculator 14, the deviation Δ | φ | between the magnitude of the estimated magnetic flux output from the subtractor 16 and the command value becomes zero, for example, by the following equation. , A magnetic flux correction amount φcmp is calculated by proportional integral control.

[0201]

(Equation 23)

Here, s: Laplace operator, Kp: proportional gain, Ki: integral gain.

That is, the magnitude of the estimated magnetic flux |
When φ | is larger than the corrected magnetic flux command φ ^* cmp (Δ | φ |> 0), the magnetic flux command φ ^* is increased, that is, a positive magnetic flux correction amount φcmp is output.
Gains Kp and Ki are set.

As described above, in the power converter using the speed sensorless vector control of the present embodiment, when the three-phase inverter 1 performs the CVVF operation, the magnitude of the estimated magnetic flux | φ | The magnetic flux correction amount φcmp is calculated based on the deviation Δ | φ | from the magnetic flux command φ ^* cmp such that the deviation Δ | φ | becomes zero.

In the case of CVVF, unless the magnetic flux command matches the actual magnetic flux amount, the command value of the output voltage does not match the actual output voltage. When the actual magnetic flux length applied to the induction motor 2 matches the magnetic flux command length, each state quantity of the induction motor 2 and each command match, and the output torque of the three-phase inverter 1 follows the command. Can be. Operation is possible even in the one-pulse mode, and the voltage of the three-phase inverter 1 can be used to the maximum.

As described above, even in the case where the three-phase inverter 1 performs the CVVF operation in which the magnitude of the output voltage is constant, control can be performed while the magnitude of the output voltage is fixed at the maximum value. The capacity can be reduced.

(Sixth Embodiment) FIG. 9 shows a magnetic flux correction amount calculator 1 of a magnetic flux command correction unit 10 in a power converter using a speed sensorless vector control according to the present embodiment.
2 is a block diagram showing an example of a schematic configuration of FIG. 2, in which the same elements as those in FIG. 1 and FIG. 5 are denoted by the same reference numerals, and the description thereof will be omitted;

That is, as shown in FIG. 9, the magnetic flux correction amount calculator 12 of the present embodiment includes a d-axis magnetic flux calculator 20
It comprises a subtractor 16 and a second magnetic flux correction amount calculator 14.

The d-axis magnetic flux calculator 20 calculates the voltage commands Vd ^* and Vq ^* calculated by the voltage command calculator 6 and the phase current I of the induction motor 2 detected by the current detector 4.
u, Iw, and at least one of the torque axis current command Iq ^* and the magnetic flux axis current command Id ^* calculated by the current command calculation unit 5, the d-axis magnetic flux on the dq-axis rotating coordinate system. Calculate φd.

The subtractor 16 subtracts the magnetic flux command φ ^* cmp corrected by the magnetic flux command correction unit 10 from the d-axis magnetic flux magnitude φd calculated by the d-axis magnetic flux calculator 20,
The deviation Δ | φ | is calculated.

The second magnetic flux correction amount calculator 14 has a subtractor 1
6, the magnetic flux correction amount φcmp is calculated based on the magnetic flux deviation Δ | φ |

Next, the operation of the power converter using the speed sensorless vector control of the present embodiment configured as described above will be described.

Here, only the operation of the portions different from those of FIGS. 1 and 5 will be described.

In FIG. 9, in the d-axis magnetic flux calculator 20,
For example, the calculation of the d-axis magnetic flux estimation is performed by the above-described equations (21), (22), and (23).

In this case, as a method of estimating the d-axis magnetic flux,
There are many other operations besides the above-mentioned operations, and the method is not limited here.

The subtractor 16 subtracts the corrected magnetic flux command value φ ^* cmp from the estimated and calculated d-axis magnetic flux φd output from the d-axis magnetic flux calculator 20.

The output Δ | φ | from the subtracter 16 is obtained by calculating the estimated d-axis magnetic flux φd and the corrected magnetic flux command value φ ^* cm.
represents the deviation from p and is input to the second magnetic flux correction amount calculator 14.

In the second magnetic flux correction amount calculator 14, the deviation Δ | φ | between the estimated and calculated d-axis magnetic flux φd output from the subtractor 16 and the corrected magnetic flux command value φ ^* cmp is zero. In such a manner, the magnetic flux correction amount φcmp is calculated by the following equation, for example, by proportional integral control.

[0219]

(Equation 24)

Here, s: Laplace operator, Kp: proportional gain, Ki: integral gain.

That is, the estimated d-axis magnetic flux φd
Is larger than the corrected magnetic flux command φ ^* cmp (Δ |
For φ |> 0), the gains Kp and Ki are set so as to increase the magnetic flux command φ ^* , that is, to output a positive magnetic flux correction amount φcmp.

As described above, in the power converter using the speed sensorless vector control according to the present embodiment, the magnitude of the actual d-axis magnetic flux generated in the induction motor 2 when the three-phase inverter 1 performs the CVVF operation. Based on the deviation Δ | φ | between φd and the corrected magnetic flux command φ ^* cmp, this deviation Δ |
The magnetic flux correction amount φcmp is calculated so that φ | becomes zero.

In the vector control, control is performed so that the d-axis and the magnetic flux axis coincide, that is, the q-axis magnetic flux is zero. In the case of the CVVF operation, unless the d-axis magnetic flux actually generated in the induction motor 2 matches the magnetic flux command, the voltage command does not match the actual output voltage. By estimating and calculating the d-axis magnetic flux of the induction motor 2 and calculating the magnetic flux command amount in accordance with the deviation from the magnetic flux command, each state quantity of the induction motor 2 and each command match, and the three-phase inverter 1 The output torque can follow the command. Operation is possible even in the one-pulse mode, and the voltage of the three-phase inverter 1 can be used to the maximum.

In particular, in this case, compared with the fifth embodiment, the amount of operation is transiently small, and as a result, the program size related to the operation can be reduced.

As described above, even when the three-phase inverter 1 performs the CVVF operation in which the magnitude of the output voltage is constant, the control can be performed while the magnitude of the output voltage is fixed at the maximum value. The capacity can be reduced.

(Seventh Embodiment) FIG. 10 is a block diagram showing a schematic configuration example of a magnetic flux correction amount calculator 12 of a magnetic flux command correction unit 10 in a power converter using speed sensorless vector control according to the present embodiment. 1 and 5, the same elements as those in FIGS. 1 and 5 are denoted by the same reference numerals, and description thereof will be omitted. Only different parts will be described here.

That is, as shown in FIG. 10, the magnetic flux correction amount calculator 12 of the present embodiment is
, Induced voltage length calculator 22, and induced voltage reference calculator 23
, A subtractor 16 and a second magnetic flux correction amount calculator 14.

The induced voltage calculator 21 calculates the voltage commands Vd ^* and Vq ^* calculated by the voltage command calculator 6 and the phase current I of the induction motor 2 detected by the current detector 4.
u, Iw, and at least one of the torque axis current command Iq ^* and the magnetic flux axis current command Id ^* calculated by the current command calculation unit 5, the d-axis induced voltage on the dq-axis rotating coordinate system. Calculate Ed and q-axis induced voltage Eq.

Based on the d-axis induced voltage Ed and the q-axis induced voltage Eq calculated by the induced voltage calculator 21, the induced voltage length calculator 22 calculates the induced voltage length indicating the magnitude | E | of the induced voltage. Is calculated.

The induced voltage reference calculator 23 calculates the magnetic flux command φ ^* cmp corrected by the magnetic flux command corrector 10 and the output frequency ωi of the three-phase inverter 1 calculated by the output frequency calculator 11. , The induced voltage reference Eref
Is calculated.

The subtractor 16 subtracts the induced voltage reference Eref computed by the induced voltage reference computing unit 23 from the induced voltage length | E | computed by the induced voltage length computing unit 22 to obtain a deviation Δ | E | Is calculated.

The second magnetic flux correction amount calculator 14 has a subtractor 1
The magnetic flux correction amount φcmp is calculated on the basis of the induced voltage deviation Δ | E |

Next, the operation of the power converter using the speed sensorless vector control of the present embodiment configured as described above will be described.

Here, only the operation of the portions different from those of FIGS. 1 and 5 will be described.

In FIG. 10, the induced voltage calculator 21 calculates the induced voltage by the following equation, for example.

[0236]

(Equation 25)

[0237]

(Equation 26)

The d-axis induced voltage Ed and q-axis induced voltage Eq output from the induced voltage calculator 21 are input to the induced voltage length calculator 22.

The induced voltage length calculator 22 calculates the magnitude | E | of the induced voltage estimated by the following equation, for example.

[0240]

[Equation 27]

The induced voltage reference computing unit 23 computes the induced voltage reference Eref based on the corrected magnetic flux command φ ^* cmp and the output frequency ωi of the three-phase inverter 1 by, for example, the following equation.

[0242]

[Equation 28]

The subtractor 16 subtracts the induced voltage reference Eref output from the induced voltage reference computing unit 23 from the estimated computed magnitude of the induced voltage | E | output from the induced voltage computing unit 21. You.

The output Δ | E | from the subtracter 16 is obtained by calculating the magnitude of the estimated induced voltage | E |
The deviation from ref is input to the second magnetic flux correction amount calculator 14.

In the second magnetic flux correction amount calculator 14, the deviation Δ | E | between the magnitude | E | of the estimated and calculated induced voltage output from the subtractor 16 and the induced voltage reference Eref becomes zero. As described above, the magnetic flux correction amount φcmp is calculated by, for example, the following equation by proportional integral control.

[0246]

(Equation 29)

S: Laplace operator, Kp: proportional gain, Ki: integral gain.

That is, when the magnitude | E | of the induced voltage estimated and calculated is larger than the induced voltage reference Eref (Δ
| E |> 0), such as increasing the magnetic flux command φ ^*
That is, the gains Kp and Ki are set so as to output a positive magnetic flux correction amount φcmp.

As described above, in the power converter using the speed sensorless vector control of the present embodiment, when the three-phase inverter 1 performs the CVVF operation, the magnitude of the induced voltage | E | Based on the deviation Δ | E | from the voltage reference Eref, the magnetic flux correction amount φcmp is calculated so that the deviation Δ | E | becomes zero.

In the case of the CVVF operation, if the magnetic flux command does not match the actual magnetic flux amount, the induced voltage reference does not match the magnitude of the actual induced voltage. By calculating the magnetic flux correction amount on the basis of the deviation between the estimated and calculated induced voltage and the induced voltage reference, each state quantity of the induction motor 2 and its respective commands match,
The output torque of the three-phase inverter 1 can follow the command. Operation is possible even in the one-pulse mode, and the voltage of the three-phase inverter 1 can be used to the maximum.

As described above, even when the three-phase inverter 1 performs the CVVF operation in which the magnitude of the output voltage is constant, control can be performed while the magnitude of the output voltage is fixed at the maximum value. The capacity can be reduced.

(Eighth Embodiment) FIG. 11 is a block diagram showing a schematic configuration example of a magnetic flux correction amount calculator 12 of a magnetic flux command correction unit 10 in a power converter using speed sensorless vector control according to the present embodiment. 1 and 5, the same elements as those in FIGS. 1 and 5 are denoted by the same reference numerals, and description thereof will be omitted. Only different parts will be described here.

That is, as shown in FIG. 11, the magnetic flux correction amount calculator 12 of the present embodiment is
, An induced voltage reference calculator 23, a subtractor 16, and a second magnetic flux correction amount calculator 14.

The induced voltage calculator 21 calculates the voltage commands Vd ^* and Vq ^* calculated by the voltage command calculator 6 and the phase current I of the induction motor 2 detected by the current detector 4.
u, Iw, and at least one of the torque axis current command Iq ^* and the magnetic flux axis current command Id ^* calculated by the current command calculation unit 5, the d-axis induced voltage on the dq-axis rotating coordinate system. Calculate Ed and q-axis induced voltage Eq.

The induced voltage reference computing unit 23 is based on the magnetic flux command φ ^* cmp corrected by the magnetic flux command correcting unit 10 and the output frequency ωi of the three-phase inverter 1 calculated by the output frequency calculating unit 11. , The induced voltage reference Eref
Is calculated.

The subtractor 16 calculates the induced voltage reference computing unit 2 from the q-axis induced voltage Eq computed by the induced voltage computing unit 21.
Then, the deviation Δ | E | is calculated by subtracting the induced voltage reference Eref calculated in step 3.

The second magnetic flux correction amount calculator 14 has a subtractor 1
The magnetic flux correction amount φcmp is calculated on the basis of the induced voltage deviation Δ | E |

Next, the operation of the power converter using the speed sensorless vector control of the present embodiment configured as described above will be described.

Here, only the operation of the portions different from those in FIGS. 1 and 5 will be described.

In FIG. 11, the induced voltage calculator 21 calculates the induced voltage estimation by, for example, the above-described equations (27) and (28).

The induced voltage reference calculator 23 calculates the induced voltage reference Eref based on the corrected magnetic flux command φ ^* cmp and the output frequency ωi of the three-phase inverter 1 by, for example, the above-described equation (30). .

The subtractor 16 subtracts the induced voltage reference Eref output from the induced voltage reference arithmetic unit 23 from the q-axis induced voltage Eq which is one output from the induced voltage arithmetic unit 21.

The output Δ | E | from the subtractor 16 represents the deviation between the estimated and calculated q-axis induced voltage Eq, which is the output from the subtracter 16, and the induced voltage reference Eref. The data is input to the arithmetic unit 14.

In the second magnetic flux correction amount calculator 14, the estimated and calculated q-axis induced voltage Eq, which is the output from the subtractor 16, is calculated.
The magnetic flux correction amount φcmp is calculated by proportional integral control using, for example, the following equation so that the difference Δ | E | between the induced voltage reference Eref and the induced voltage reference Eref becomes zero.

[0265]

[Equation 30]

S: Laplace operator, Kp: proportional gain, Ki: integral gain.

That is, when the actual q-axis induced voltage Eq is larger than the induced voltage reference Eref (Δ | E |> 0), the magnetic flux command φ ^* is increased, that is, the positive magnetic flux correction amount φcmp is increased. Gains Kp and Ki are set to output.

As described above, in the power converter using the speed sensorless vector control according to the present embodiment, when the three-phase inverter 1 performs the CVVF operation, the magnitude Eq of the estimated calculated q-axis induced voltage and the induced Eq. Based on the deviation Δ | E | from the voltage reference Eref, the magnetic flux correction amount φcmp is calculated so that the deviation Δ | E | becomes zero.

In the case of performing vector control, only the q-axis induced voltage is generated and no d-axis induced voltage is generated in order to make the magnetic flux coincide with the d-axis. When the three-phase inverter 1 performs the CVVF operation, if the magnetic flux command does not match the actual magnetic flux amount, the induced voltage reference does not match the actual q-axis induced voltage. By calculating the magnetic flux correction amount based on the deviation between the estimated and calculated q-axis induced voltage and the induced voltage reference, each state quantity of the induction motor 2 and its respective commands match, and the output torque of the three-phase inverter 1 Can follow the command. Operation is possible even in the one-pulse mode, and the voltage of the three-phase inverter 1 can be used to the maximum.

As described above, even when the three-phase inverter 1 performs the CVVF operation in which the magnitude of the output voltage is constant, control can be performed while the magnitude of the output voltage is fixed at the maximum value. The capacity can be reduced.

(Ninth Embodiment) FIG. 12 is a block diagram showing a schematic configuration example of an output frequency calculation unit 11 in a power converter using speed sensorless vector control according to the present embodiment. The same elements as those described above are denoted by the same reference numerals and description thereof will be omitted, and only different parts will be described here.

This embodiment is different from the first embodiment in that the output frequency calculating unit 1 is provided when the motor connected to the three-phase inverter 1 is limited to the induction motor 2 in particular.
1 is specified.

That is, as shown in FIG. 12, the output frequency calculator 11 of the present embodiment comprises a rotor rotation frequency calculator 24, a slip frequency calculator 25, and an adder.

[0274] The rotor rotation frequency calculation unit 24 includes a d-axis voltage command Vd ^* and a q-axis voltage command Vq ^* output from the voltage command calculation unit 6, and a magnetic flux axis (d-axis output) output from the current command calculation unit 5. Based on at least one of the current command Id ^* , the torque axis (q-axis) current command Iq ^* , and the phase currents Iu, Iw of the induction motor 2 detected by the current detector 4; Estimate and calculate the rotation frequency of the rotor,
Outputs the rotor frequency ωrh.

The slip frequency calculating unit 25 detects the magnetic flux axis (d-axis) current command Id ^* , the torque axis (q-axis) current command Iq ^* , and the current detector 4, which are the outputs from the current command calculating unit 5. The slip frequency of the induction motor 2 is calculated based on at least one of the phase currents Iu and Iw of the induction motor 2, and the slip frequency ωsh is output.

The adder 26 outputs the output ωrh from the rotor frequency calculator 24 and the output ωsh from the slip frequency calculator 25.
And outputs the output frequency of the three-phase inverter 1.

Next, the operation of the power converter using the speed sensorless vector control of the present embodiment configured as described above will be described.

Here, only the operation of the portions different from those of FIGS. 1 and 5 will be described.

In FIG. 12, the rotor frequency calculating section 24
Then, the d-axis voltage command Vd ^* and the q-axis voltage command Vq ^* output from the voltage command calculation unit 6, the magnetic flux axis (d-axis) current command Id ^* and the torque axis (q
Axis) The rotational frequency of the rotor of the induction motor 2 is estimated and calculated based on the current command Iq ^* and the phase currents Iu and Iw of the induction motor 2 detected by the current detector 4, and the rotor frequency ωrh is output.

In the slip frequency calculating section 25, the magnetic flux axis (d-axis) current command I, which is the output from the current command calculating section 5,
d ^* , torque axis (q-axis) current command Iq ^* , current detector 4
The slip frequency to be given to the induction motor 2 is calculated based on the phase currents Iu and Iw of the induction motor 2 detected by the above, and the slip frequency ωsh is output.

In this case, the slip frequency calculating section 25 calculates the slip frequency ωsh by the following equation, for example.

[0282]

(Equation 31)

In the adder 26, the rotor frequency calculator 24
Is added to the slip frequency ωsh output from the slip frequency calculator 25, and the output frequency ωi of the three-phase inverter 1 is calculated.

Here, the rotor frequency calculating section 24 includes a rotor frequency reference calculating section 36 as shown in FIG.
, A rotor frequency correction amount calculation unit 37 and an adder 38.

In the rotor frequency reference calculation unit 36, the d-axis voltage command Vd ^* and q-axis voltage command Vq ^* output from the voltage command calculation unit 6 and the magnetic flux axis (d-axis ) Current command Id ^* , torque axis (q-axis) current command Iq ^* , induction motor 2 detected by current detector 4
Based on the respective phase currents Iu and Iw, the reference amount ωrh ^* of the rotation frequency of the rotor of the induction motor 2 is estimated and calculated.

In the rotor frequency correction amount calculating section 37, the d-axis voltage commands Vd ^* , q output from the voltage command calculating section 6 are output.
The shaft voltage command Vq ^* , the magnetic flux axis (d-axis) current command Id ^* , the torque axis (q-axis) current command Iq ^* , which are the outputs from the current command calculation unit 5, and the induction motor 2 detected by the current detector 4. A correction amount ωrhcmp to the rotation frequency of the rotor of the induction motor 2 is calculated based on the phase currents Iu and Iw.

In the adder 38, the rotor frequency reference amount ωrh ^* output from the rotor frequency reference operation unit 36 and the rotor frequency correction amount ωrhcmp output from the rotor frequency correction amount operation unit 37 are added. Rotor frequency ωrh
Is calculated.

Here, the rotor frequency correction amount calculating section 37
Is, for example, as shown in FIG.
And a proportional-integral controller 40.

In the q-axis magnetic flux calculator 39, the d-axis voltage command Vd ^* and the q-axis voltage command Vq ^* , which are the outputs from the voltage command calculator 6, and the flux axis which is the output from the current command calculator 5,
(D-axis) current command Id ^* , torque axis (q-axis) current command I
Based on q ^* and each phase current Iu, Iw of the induction motor 2 detected by the current detector 4, for example,
The q-axis magnetic flux φq is estimated and calculated by the equations (2) and (23).

The calculated q-axis magnetic flux φq is
It is input to the proportional-integral controller 40, and the rotor frequency correction amount ωrhcmp is calculated by the following equation, for example.

[0291]

(Equation 32)

Here, s: Laplace operator, Kp: proportional gain, Ki: integral gain.

When the rotor frequency is accurately calculated, it is equivalent to the slip frequency type vector control with a speed sensor, the d-axis and the magnetic flux axis coincide, and no q-axis magnetic flux is generated.

As described above, the q-axis magnetic flux φq is estimated and calculated, and the rotor frequency is corrected based on the q-axis magnetic flux φq, thereby correcting the error in the rotor frequency and matching the d-axis with the magnetic flux axis. Speed sensorless vector control can be performed.

As described above, in the power converter using the speed sensorless vector control according to the present embodiment, the rotor frequency of the induction motor 2 is estimated and calculated from each state quantity of the induction motor 2, and each state of the induction motor 2 is calculated. By calculating the slip frequency to be given from the quantity and adding the rotor frequency and the slip frequency to obtain the output frequency of the three-phase inverter 1, control can be performed so that the magnetic flux axis and the d axis coincide. .

When the three-phase inverter 1 performs the CVVF operation, a magnetic flux command φ based on the difference between each state quantity such as current, voltage, and magnetic flux of the induction motor 2 and each corresponding command.
By correcting ^* , each state quantity of the induction motor 2 matches each command, and the output torque of the three-phase inverter 1 can follow the command. Operation is possible even in the one-pulse mode, and the voltage of the three-phase inverter 1 can be used to the maximum.

As described above, even when the three-phase inverter 1 performs the CVVF operation in which the magnitude of the output voltage is constant, control can be performed while the magnitude of the output voltage is fixed at the maximum value. The capacity can be reduced.

(Modification of Ninth Embodiment) FIG.
FIG. 13 is a block diagram illustrating another configuration example of the rotor frequency correction amount calculation unit 37.

In FIG. 15, the rotor frequency correction amount calculating section 37 comprises a d-axis induced voltage calculating section 41 and a proportional integral controller 40.

In the d-axis induced voltage calculator 41, the d-axis voltage command Vd ^* and the q-axis voltage command Vq ^* output from the voltage command calculator 6 and the magnetic flux axis (d Axis) current command Id ^* , torque axis (q axis) current command I
Based on q ^* and each phase current Iu, Iw of the induction motor 2 detected by the current detector 4, for example,
The d-axis induced voltage Ed is estimated and calculated by the equation (2).

Then, the calculated d-axis induced voltage Ed
Is input to the proportional-integral controller 40, and the rotor frequency correction amount ωrhcmp is calculated by, for example, the following equation.

[0302]

[Equation 33]

Here, s: Laplace operator, Kp: proportional gain, Ki: integral gain.

When the rotor frequency is accurately calculated, it is equivalent to the slip frequency type vector control with a speed sensor, the d-axis and the magnetic flux axis coincide, and no q-axis induced voltage is generated.

As described above, the d-axis induced voltage Ed is estimated and calculated, and the rotor frequency is corrected based on the d-axis induced voltage Ed. . Can be performed. (Tenth Embodiment) FIG. 16 is a block diagram showing a schematic configuration example of a power conversion device using speed sensorless vector control according to the present embodiment, and the same elements as those in FIG. The description thereof is omitted, and only different portions will be described here.

In this embodiment, in the first to ninth embodiments, the configuration example in the case of driving an induction motor as a motor is shown. An example of a configuration in a case where application is possible is shown.

[0307] Here, as an example, a configuration example in which a permanent magnet motor is driven as the motor is shown.

That is, as shown in FIG. 16, the power converter of the present embodiment uses the induction motor 2 shown in FIG.
Is replaced by a permanent magnet motor 41.

FIG. 16 shows a three-phase inverter 1 and a filter capacitor 3 connected to the DC side of the three-phase inverter 1.
And a permanent magnet motor 2 connected to the AC side of the three-phase inverter 1 to form a main circuit, and performs motor drive control by vector control.

[0310] Next, the operation of the power converter using the speed sensorless vector control of the present embodiment configured as described above will be described.

In FIG. 14, a magnetic flux command correction unit 10 receives a magnetic flux command φ ^* , corrects it as described in detail later, and outputs a corrected magnetic flux command φ ^* cmp.

The corrected magnetic flux command φ ^* cmp and the torque command Tm ^* are input to the current command calculation unit 5, and the magnetic flux axis (d-axis) current command Id ^* and the torque axis (q
(Axis) current command Iq ^* is calculated.

[0313]

(Equation 34)

However, ΔL: Ld-Lq.

The magnetic flux axis (d-axis) current command Id ^* and the torque axis (q-axis) current command Iq ^* are input to the voltage command calculator 6, and the d-axis voltage command Vd ^* and the q
The shaft voltage command Vq ^* is calculated.

[0316]

(Equation 35)

Here, R: resistance, Ld: d-axis inductance, Lq: q-axis inductance, ωi: inverter output frequency, φf: permanent magnet magnetic flux.

The coordinate conversion unit 7 has a d-axis voltage command Vd ^* and a q-axis voltage command Vq ^* which are outputs from the voltage command calculation unit 6 ^.
Is input, and the magnitude of the voltage command | V
And the phase angle θv from the d-axis are calculated.

[0319]

[Equation 36]

The gate control unit 8 calculates the phase angle θv of the voltage command output from the coordinate conversion unit 7 from the d-axis and the output signal from the integration unit 9 from the stationary coordinate system a-axis of the d-axis of the rotating coordinate system. The gate signal is generated based on the phase angle θab.

Since the operation of the gate control unit 8 is the same as the operation of the gate control unit 8 in the first embodiment, the description is omitted here.

In the magnetic flux command correction unit 10, the d-axis voltage command Vd ^* and the q-axis voltage command Vq ^* output from the voltage command calculation unit 6 and the magnitude | of the voltage command output from the coordinate conversion unit 7 Based on V | and each phase current Iu, Iw of the permanent magnet motor 41 detected by the current detector 4, the difference between the actual state quantity of the permanent magnet motor 41 and the corresponding command is determined, and the magnetic flux is determined. The command φ ^* is corrected. Since the voltage of the permanent magnet motor 41 is generally represented by magnetic flux × frequency, the command of the output voltage is corrected by correcting the magnetic flux command φ ^* .

Note that this magnetic flux command correction unit 10 is also the same as the magnetic flux command correction unit 10 of the first embodiment.
The same configuration can be taken.

The output frequency calculator 11 outputs the d-axis voltage command Vd ^* and the q-axis voltage command Vq ^* output from the voltage command calculator 6 and the respective phases of the permanent magnet motor 41 detected by the current detector 4. Output frequency ωi of three-phase inverter 1 is calculated based on currents Iu and Iw.

Here, the output frequency calculating section 11 includes, as shown in FIG. 17, for example, an output frequency reference amount calculating section 27,
It comprises an output frequency correction amount calculation unit 28 and an adder 31.

The output frequency reference amount calculating section 27 is composed of an induced voltage calculator 42 and a divider 32.

The induced voltage calculator 42 calculates the d-axis induced voltage Ed and the q-axis induced voltage Eq by, for example, the following equation.

[0328]

(37)

The q-axis induced voltage Eq calculated by the induced voltage calculator 42 is input to the divider 32 and divided by the corrected magnetic flux command value φ ^* cmp. The output from the divider 32 becomes an output frequency reference ωiref.

On the other hand, the output frequency correction amount calculating section 28 comprises an induced voltage calculator 42 and a proportional-integral controller 33.

[0331] Among the induced voltages calculated by the induced voltage calculator 42, the d-axis induced voltage Ed is the proportional-integral controller 3
3 is input.

In the proportional integral controller 33, the output frequency correction amount Δωi is calculated by the following equation, for example.

[0333]

(38)

Here, Kp: proportional gain, Ki: integral gain.

This output frequency correction amount Δωi is
The output frequency ωi of the three-phase inverter 1 is calculated by adding the output frequency reference amount ωiref by the adder 31.

As described above, similarly to the case of the drive control of the induction motor 2 described above, also in the case of the drive control of the permanent magnet motor 41, the vector control is established, that is, the d axis and the magnetic flux axis coincide. In this case, no d-axis induced voltage is generated.

By correcting the output frequency ωi of the three-phase inverter 1 based on the d-axis induced voltage, it is possible to make the magnetic flux axis coincide with the d-axis by compensating the axis deviation.

Thus, the output frequency ωi of the three-phase inverter 1 calculated by the output frequency calculator 11 is
The signal is input to the integration section 9 and the integrated value is output. The output of the integration unit 9 is the rotation phase angle θab from the stationary coordinate system a axis to the rotating coordinate system d axis.

As described above, in the power converter using the speed sensorless vector control of the present embodiment, when the three-phase inverter 1 performs the CVVF operation, each state quantity such as the current, voltage, and magnetic flux of the permanent magnet motor 41 is changed. By correcting the magnetic flux command φ ^* on the basis of the difference between the commands and the corresponding commands, the state quantities of the permanent magnet motor 41 and the commands match, and the output torque of the three-phase inverter 1 follows the command. Can be done. Operation is possible even in the one-pulse mode, and the voltage of the three-phase inverter 1 can be used to the maximum.

(Other Embodiments) The First to First Embodiments
0, in the voltage command calculation unit 6,
Based on only the magnetic flux axis (d-axis) current command Id ^* and the torque axis (q-axis) current Iq ^* ,
The case where the d-axis voltage command Vd ^* and the q-axis voltage command Vq ^* are calculated has been described, but the present invention is not limited to this.

For example, the phase currents Iu and Iw of the electric motor 2 are also inputted, and the magnetic flux axis (d-axis) current command Id ^* and the torque axis (q
Axis) based on the current Iq ^* and the phase currents Iu and Iw of the motor detected by the current detector 4, the d-axis voltage command Vd
^* And the q-axis voltage command Vq ^* may be calculated. Iu and Iw are calculated according to the above-mentioned equation (6), for example.
d, Iq.

The arithmetic expressions in this case are the d-axis voltage command Vd ^* and the q-axis voltage command Vd ^* in the above-mentioned equation (2).
As an arithmetic expression of q ^* , instead of Vd ^* = R1 · Id ^* −ωi · σL1 · Iq ^* Vq ^* = R1 · Iq ^* + ωi · L1 · Id ^* , Vd ^* = R1 · Id ^* −ωi · σL1 · Iq Vq ^* = R1 · Iq ^* + ωi · σL1 · Id + ωi · L
2 / M ² · Id ^* in some cases.

[0343]

As described above, according to the power converter of the present invention, even when the three-phase inverter performs the CVVF operation in which the magnitude of the output voltage is constant by the speed sensorless vector control, the information of the motor can be obtained. The torque output of the three-phase inverter can be made to follow the command by correcting the magnetic flux command on the basis of the above and making the state quantities such as current, voltage and magnetic flux of the electric motor coincide with the corresponding command.

As a result, the output voltage can be controlled with the magnitude of the output voltage fixed at the maximum value, the operation can be performed even in the one-pulse mode, and the voltage of the three-phase inverter The capacity can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of a power converter using speed sensorless vector control according to the present invention.

FIG. 2 is a block diagram showing a detailed first configuration example of an output frequency calculation unit in the power converter using the speed sensorless vector control according to the first embodiment;

FIG. 3 is a block diagram showing a detailed second configuration example of an output frequency calculator in the power converter using the speed sensorless vector control according to the first embodiment;

FIG. 4 is a block diagram showing a detailed third configuration example of an output frequency calculator in the power converter using the speed sensorless vector control according to the first embodiment;

FIG. 5 is a block diagram showing a second embodiment of the power converter using the speed sensorless vector control according to the present invention.

FIG. 6 is a block diagram showing a third embodiment of a power converter using speed sensorless vector control according to the present invention.

FIG. 7 is a block diagram showing a fourth embodiment of the power converter using speed sensorless vector control according to the present invention.

FIG. 8 is a block diagram showing a fifth embodiment of the power converter using the speed sensorless vector control according to the present invention.

FIG. 9 is a block diagram showing a sixth embodiment of the power converter using the speed sensorless vector control according to the present invention.

FIG. 10 is a block diagram showing a seventh embodiment of the power converter using the speed sensorless vector control according to the present invention.

FIG. 11 is a block diagram showing an eighth embodiment of a power converter using speed sensorless vector control according to the present invention.

FIG. 12 is a block diagram showing a ninth embodiment of a power converter using speed sensorless vector control according to the present invention.

FIG. 13 is a block diagram showing a detailed first configuration example of a rotor frequency calculation unit in a power converter using speed sensorless vector control according to the ninth embodiment;

FIG. 14 is a block diagram showing a detailed second configuration example of the rotor frequency calculation unit in the power converter using the speed sensorless vector control according to the ninth embodiment.

FIG. 15 is a block diagram showing a detailed third configuration example of the rotor frequency calculation unit in the power converter using the speed sensorless vector control according to the ninth embodiment;

FIG. 16 is a block diagram showing a tenth embodiment of a power converter using speed sensorless vector control according to the present invention.

FIG. 17 is a block diagram showing a detailed configuration example of an output frequency calculation unit in a power converter using speed sensorless vector control according to the tenth embodiment.

FIG. 18 is a block diagram showing a schematic configuration example of a power conversion device to which conventional speed sensorless vector control is applied.

FIG. 19 is a block diagram showing an example of an output frequency calculation unit in a power conversion device to which conventional speed sensorless vector control is applied.

FIG. 20 is a conceptual diagram showing a relationship between coordinate systems.

FIG. 21 is a vector diagram of the induction motor in a steady state with no axis deviation.

FIG. 22 is a vector diagram of the induction motor in a steady state with an axis shift.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... 3 phase inverter, 2 ... induction motor, 3 ... filter capacitor, 4 ... current detector, 5 ... current command calculation part, 6 ... voltage command calculation part, 7 ... coordinate conversion part, 8 ... gate control part, 9 ... Integrator, 10 Magnetic flux command corrector, 11 Output frequency calculator, 12 Magnetic flux correction calculator, 13 Adder, 14 Second magnetic flux corrector, 15 Output voltage length calculator, 16 ... subtractor, 17 ... DC voltage detector, 18 ... second output voltage length calculator, 19 ... magnetic flux length calculator, 20 ... d-axis magnetic flux calculator, 21 ... induced voltage calculator, 22 ... induced voltage length calculation 23, an induced voltage reference arithmetic unit, 24, a rotor frequency arithmetic unit, 25, a sliding frequency arithmetic unit, 26, an adder, 27, an output frequency reference amount arithmetic unit, 28, an output frequency correction amount arithmetic unit, 29, proportional Integrator, 30 Multiplier, 31 Addition , 32: divider, 33: proportional integral controller, 34: coordinate system converter, 35: subtractor, 36: rotor frequency reference calculator, 37: rotor frequency correction amount calculator, 38: adder, 39: q Axial magnetic flux calculator, 40: proportional integral controller, 41: permanent magnet motor, 42: induced voltage calculator, φ ^* : magnetic flux command, φ ^* cmp: corrected magnetic flux command, Tm ^* : torque command, Id ^* ... Magnetic flux axis (d-axis) current command, Iq ^* : torque axis (q-axis) current command, Vd ^* : d-axis voltage command, Vq ^* : q-axis voltage command, | V |: voltage command length (magnitude), θv ... Phase angle of voltage command from d-axis, θab ... Phase angle of fixed d-axis of rotating coordinate system d-axis, s ... Laplace operator, ωiref ... Output frequency reference amount, Δωi ... Output frequency correction amount, Id ... Magnetic flux axis (d axis) current, Iq ... torque axis (q axis) current, i: inverter output frequency, R1: primary resistance of induction motor 2, R2: secondary resistance of induction motor 2, L1: primary inductance of induction motor 2, L2: secondary inductance of induction motor 2, M: induction motor , L1: leakage inductance of the induction motor 2, φcmp: magnetic flux command correction amount, Vdc: DC link voltage, | V | ^* : magnitude of output voltage actually output from the inverter, R: permanent magnet motor Ld: d-axis inductance of the permanent magnet motor 41, Lq: q-axis inductance of the permanent magnet motor 41, φf: permanent magnet magnetic flux amount of the permanent magnet motor 41.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5H576 BB09 BB10 CC01 DD02 DD04 DD07 EE01 GG05 GG10 HB01 JJ05 JJ22 JJ24 JJ25 LL14 LL22 LL24 LL30 LL34 LL60

Claims (9)

[Claims] 1. A converter for converting a direct current into an alternating current of an arbitrary frequency.
A main circuit comprising a three-phase inverter, a filter capacitor connected to the DC side of the three-phase inverter, and a motor connected to and driven by the AC side of the three-phase inverter; Vector control means for controlling the three-phase inverter without using a speed detector on a dq-axis rotating coordinate system having an axis (torque axis) orthogonal to the d-axis as a q-axis. A current command calculation for calculating a q-axis current command as a torque axis current command and a d-axis current command as a flux axis current command based on a magnetic flux command and a torque command. Means, at least a torque axis current command and a magnetic flux axis current command calculated by the current command calculation means are input, and a d-axis voltage command and a q-axis voltage command are calculated based on the inputs. Voltage command calculating means, and a d-axis voltage command and a q-axis voltage command calculated by the voltage command calculating means, and the magnitude of the voltage command comprising the d-axis voltage command and the q-axis voltage command and the magnetic flux Coordinate conversion means for calculating an angle of a voltage command with respect to an axis; current detection means for detecting a current flowing through the motor; current of the motor detected by the current detection means and current calculated by the current command calculation means An output frequency calculating means for calculating an output frequency of the three-phase inverter based on at least one of a command and a voltage command calculated by the voltage command calculating means; and a three-phase calculated by the output frequency calculating means. Integrating means for receiving the output frequency of the inverter as an input, integrating the input output frequency of the three-phase inverter to calculate a phase, Ri based on the angle of the voltage command, which is calculated the calculated phase as by the coordinate transformation means, said 3
A gate control unit for controlling a gate of the phase inverter; a voltage command calculated by the voltage command calculation unit; a magnitude of the voltage command calculated by the coordinate conversion unit; and a current of the motor detected by the current detection unit. Magnetic flux command correction means for correcting the magnetic flux command based on at least one of the current commands calculated by the current command calculation means so as to match the state quantity of the motor with a corresponding command. A power converter using speed sensorless vector control. 2. The power converter using the speed sensorless vector control according to claim 1, wherein the magnetic flux command correction means includes a voltage command calculated by the voltage command calculation means and a calculation by the coordinate conversion means. A magnetic flux correction amount calculation for calculating a magnetic flux correction amount based on at least one of the magnitude of the detected voltage command, the current of the electric motor detected by the current detection means, and the current command calculated by the current command calculation means. Means, and an adding means for adding the magnetic flux correction amount calculated by the magnetic flux correction amount calculating means and the magnetic flux command. A power conversion apparatus using speed sensorless vector control. 3. The power converter using the speed sensorless vector control according to claim 2, wherein the magnetic flux correction amount calculating means calculates a voltage length indicating a magnitude of an output voltage of the three-phase inverter. Output voltage length calculation means; subtraction means for calculating a deviation by subtracting the magnitude of the voltage command calculated by the coordinate conversion means from the magnitude of the output voltage calculated by the output voltage length calculation means; And a second magnetic flux correction amount calculating means for calculating a correction amount of the magnetic flux based on the voltage deviation calculated by the means. A power conversion device using speed sensorless vector control, comprising: 4. The power conversion device using speed sensorless vector control according to claim 3, wherein the output voltage length calculation means includes: a voltage detection means for detecting a DC link voltage applied to the filter capacitor; A second output voltage length calculating means for calculating an output voltage length based on the DC link voltage detected by the voltage detecting means; and a power converter using speed sensorless vector control. 5. The power converter using speed sensorless vector control according to claim 2, wherein the magnetic flux correction amount calculating means includes a voltage command calculated by the voltage command calculating means and the current detecting means. Magnetic flux length calculating means for calculating a magnetic flux length indicating the magnitude of magnetic flux based on at least one of the detected electric current of the motor and the current command calculated by the current command calculating means; Subtraction means for calculating a deviation by subtracting the magnetic flux command corrected by the magnetic flux command correction means from the magnitude of the magnetic flux calculated by, based on the deviation of the magnetic flux calculated by the subtraction means,
And a second magnetic flux correction amount calculating means for calculating the magnetic flux correction amount. A power converter using speed sensorless vector control, comprising: 6. The power converter using speed sensorless vector control according to claim 2, wherein the magnetic flux correction amount calculating means includes a voltage command calculated by the voltage command calculating means and the current detecting means. D-axis magnetic flux calculating means for calculating a d-axis magnetic flux on the dq-axis rotating coordinate system based on at least one of the detected current of the motor and a current command calculated by the current command calculating means, Subtraction means for calculating a deviation by subtracting the magnetic flux command corrected by the magnetic flux command correction means from the magnitude of the d-axis magnetic flux calculated by the d-axis magnetic flux calculation means; deviation of the magnetic flux calculated by the subtraction means On the basis of the,
And a second magnetic flux correction amount calculating means for calculating the magnetic flux correction amount. A power converter using speed sensorless vector control, comprising: 7. The power converter using speed sensorless vector control according to claim 2, wherein the magnetic flux correction amount calculating means includes a voltage command calculated by the voltage command calculating means and the current detecting means. Induction for calculating a d-axis induced voltage and a q-axis induced voltage on the dq-axis rotating coordinate system based on at least one of the detected current of the motor and the current command calculated by the current command calculation means. Voltage calculating means, based on the d-axis induced voltage and the q-axis induced voltage calculated by the induced voltage calculating means, an induced voltage length calculating means for calculating an induced voltage length indicating the magnitude of the induced voltage, Based on the magnetic flux command corrected by the magnetic flux command correcting means and the output frequency of the three-phase inverter calculated by the output frequency calculating means, an induced voltage reference is performed. Induced voltage reference calculating means, subtracting the induced voltage reference calculated by the induced voltage reference calculating means from the induced voltage length calculated by the induced voltage length calculating means, and calculating a deviation; And a second magnetic flux correction amount calculating means for calculating the magnetic flux correction amount based on the deviation of the induced voltage calculated by the following. 8. The power converter using the speed sensorless vector control according to claim 2, wherein the magnetic flux correction amount calculating means includes a voltage command calculated by the voltage command calculating means and the current detecting means. Induction for calculating a d-axis induced voltage and a q-axis induced voltage on the dq-axis rotating coordinate system based on at least one of the detected current of the motor and the current command calculated by the current command calculation means. Voltage calculation means, induced voltage reference calculation means for calculating an induced voltage reference based on the magnetic flux command corrected by the magnetic flux command correction means and the output frequency of the three-phase inverter calculated by the output frequency calculation means, Subtracting the induced voltage reference calculated by the induced voltage reference calculating means from the q-axis induced voltage calculated by the induced voltage calculating means; A speed sensorless vector, comprising: subtraction means for calculating the difference; and second magnetic flux correction amount calculation means for calculating the magnetic flux correction amount based on the deviation of the induced voltage calculated by the subtraction means. Power converter using control. 9. The power converter using speed sensorless vector control according to claim 1, wherein the voltage command calculating means includes a torque axis current command and a magnetic flux axis current command calculated by the current command calculating means. And a current of the motor detected by the current detecting means, and calculating a d-axis voltage command and a q-axis voltage command based on the input. .