JP2006174524A - Inverter controller of induction motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inverter controller of an induction motor in which motor constants including the saturation characteristics of excitation inductance can be measured precisely under a state where the motor is stopping before operation. <P>SOLUTION: A coordinate conversion means for determining the biaxial component value on a fixed coordinate, a voltage model type flux operating means performing compensation of primary resistance R1 and leakage inductance and including an integration means for operating the secondary flux of the motor by using voltage information, a current model type flux operating means including a primary delay element for operating the secondary flux of the motor by using current information, a sine wave generation means for commanding excitation current containing a sine wave component to generate an AC flux, a means for detecting each amplitude value of the output signal from the voltage model type flux operating means and the current information on a fixed coordinate, and a means for detecting phase difference between the output signal from the voltage model type flux operating means and the current information on the fixed coordinate are provided, respectively, for the voltage information and current information of an induction motor. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an inverter control device for an induction motor.

  Among the conventional inverter control devices for induction motors, the following are known for obtaining the excitation inductance M, the secondary circuit time constant T2, and the secondary resistance R2 when the motor is stopped.

  The first prior art pays attention to the fact that the voltage model magnetic flux calculation circuit (voltage model) has high calculation accuracy in the high speed range, and the current model magnetic flux calculation circuit (current model) has high stability in the low speed range, Both of the outputs are corrected by the above compensation means so that stable calculation can be performed over a wide speed range from low speed to high speed, and the errors of the excitation inductance and the secondary time constant are the values of the secondary magnetic flux calculated by the current model. Paying attention to the amplitude and phase deviation, parameter adjustment means is provided to set the parameters of the current model by calculating the excitation inductance and the secondary time constant from the output difference of both models. Enables highly accurate calculation of the next time constant. (For example, see Patent Document 1)

  In addition, the second prior art correctly sets and compensates the primary resistance and the leakage inductance, gives a sinusoidal excitation current command so that an alternating magnetic flux is generated when the induction motor is stopped, and the motor flux and the current command value. The secondary circuit time constant is identified so that the phase difference of the current model magnetic flux derived from is zero, and the excitation inductance is identified so that the amplitude difference between the motor magnetic flux and the current model magnetic flux is zero. Secondary resistance is measured using constant and exciting inductance. (For example, refer to Patent Document 2).

Further, in the third prior art, the voltage output phase is set to an arbitrary fixed value set in advance, and a predetermined value is given as the output voltage command value. At this time, the primary current detection value flowing through the induction motor and its convergence value i1∞ , The magnetic flux is estimated from the primary current detection value i1 (t) and the primary resistance value at time t (φ ^ (t)), and the value obtained by multiplying the convergence value by the coefficient k becomes i1∞. And
R2 = −R1 (i1∞−i1 (t)) / (φ ^ (t) −i1 (t))
Further, using the time constant τφ of the rise of the estimated magnetic flux value (φ ^ (t)), M = R 1 · R 2 · τφ / (R 1 + R 2)
I want to ask. (For example, see Patent Document 3)

As described above, the conventional inverter control device for an induction motor obtains M and T2 by comparing two different calculated magnetic flux values of the voltage model and the current model, or uses the time constant of the rise of the estimated magnetic flux value. Or ask for it.
Japanese Examined Patent Publication No. 6-79057 JP-A-6-34724 JP 2004-144658 A

Conventional inverter control devices for induction motors are difficult to use for automatic tuning of motor electrical constants when the motor is stopped before operation, are complicated in processing, and are not suitable for measuring saturation characteristics of excitation inductance. There was a problem such as.
The present invention has been made in view of such problems, and is an inverter control device for an induction motor that can accurately measure a motor electrical constant including a saturation characteristic of an excitation inductance when the motor is stopped before operation. The purpose is to provide.
Further, even when the electric motor does not have a speed sensor, it can be applied to a machine in which the electric motor is already incorporated in a load machine, and an object is to improve control accuracy such as static / dynamic characteristics.

In order to solve the above problem, the present invention is configured as follows.

  The invention according to claim 1 performs coordinate transformation means for obtaining a biaxial component value on a fixed coordinate system for each of voltage information and current information of the induction motor, compensation of primary resistance and leakage inductance, and Voltage model type magnetic flux calculation means including integration means for calculating the secondary magnetic flux of the electric motor using voltage information, sine wave generation means for instructing an excitation current including a sine wave component so as to generate an alternating magnetic flux, and the voltage A model-type magnetic flux calculation means output signal and an amplitude value detection means for detecting each amplitude value of the current information on a fixed coordinate system, an angular frequency included in the excitation current command signal generated from the sine wave generation means, A secondary resistance value is obtained based on the maximum value of the secondary magnetic flux obtained by the amplitude value detecting means and the amplitude value of the current information.

  Further, the invention according to claim 2 performs coordinate conversion means for obtaining a biaxial component value on a fixed coordinate system and compensation of primary resistance and leakage inductance for each of voltage information and current information of the induction motor. A voltage model type magnetic flux calculating means including an integrating means for calculating the secondary magnetic flux of the electric motor using the voltage information; and a sine wave generating means for commanding an excitation current including a sine wave component so that an alternating magnetic flux is generated; An output signal of the voltage model type magnetic flux calculation means and a phase difference detection means of the current information on a fixed coordinate system are provided, an angular frequency included in an excitation current command signal generated from the sine wave generation means, and the phase difference detection A secondary circuit time constant is obtained based on the phase difference between the secondary magnetic flux obtained by the means and the current information.

  According to the third aspect of the present invention, for each of the voltage information and current information of the induction motor, coordinate conversion means for obtaining a biaxial component value on a fixed coordinate system, and compensation of primary resistance and leakage inductance are performed. A voltage model type magnetic flux calculation means including an integration means for calculating the secondary magnetic flux of the electric motor using the voltage information; a sine wave generation means for commanding an excitation current including a sine wave component so that an alternating magnetic flux is generated; An output signal of the voltage model type magnetic flux calculation means and a phase difference detection means of the current information on a fixed coordinate system are provided, an angular frequency included in an excitation current command signal generated from the sine wave generation means, and the amplitude value detection The exciting inductance is obtained based on the secondary magnetic flux obtained by the means and the maximum value of the amplitude value of the current information.

  According to a fourth aspect of the present invention, the secondary resistance, exciting inductance, and secondary circuit time constant obtained in the first to third aspects are set, and the secondary magnetic flux of the motor is calculated using the current information. A current model type magnetic flux calculating means including a first-order lag element; and a compensating means for compensating so that respective output values of the current model magnetic flux calculating means and the voltage model magnetic flux calculating means match, and the voltage model type magnetic flux The offset compensation of the integration means of the computing means is performed.

  According to a fifth aspect of the present invention, the secondary resistance, exciting inductance, and secondary circuit time constant obtained in the first to third aspects are set, and the secondary magnetic flux of the motor is calculated using the current information. A current model type magnetic flux calculating means including a first order lag element, and a compensating means for compensating the output values of the current model magnetic flux calculating means and the voltage model type magnetic flux calculating means to coincide with each other to correct the secondary resistance It is characterized by calculating.

  According to a sixth aspect of the present invention, in the fifth aspect, the correction process is repeated until the calculation value ratio before and after the correction of the secondary resistance becomes a predetermined value or less.

  According to a seventh aspect of the present invention, in the second aspect, the phase difference is detected by the phase difference detecting means so that the excitation current command signal generated from the sine wave generating means includes a DC signal, and the phase difference is calculated by the phase difference. Based on this, the saturation characteristic of the excitation inductance M is obtained.

The invention described in claim 8 is characterized in that the magnetizing inductance M is obtained from the secondary resistance R2 and the secondary circuit time constant T2 obtained from claims 1, 2, 5, and 6. .
According to the ninth aspect of the present invention, coordinate conversion means for obtaining a biaxial component value on a fixed coordinate system and compensation of primary resistance and leakage inductance are performed for each of voltage information and current information of the induction motor. A voltage model type magnetic flux calculating means including an integrating means for calculating the secondary magnetic flux of the electric motor using the voltage information; and a sine wave generating means for commanding an excitation current including a sine wave component so that an alternating magnetic flux is generated; An output signal of the voltage model type magnetic flux calculation means and an amplitude value detection means for detecting each amplitude value of the current information on a fixed coordinate system are provided, and the voltage model type magnetic flux calculation means output signal and the current on the fixed coordinate system are provided. An information phase difference detecting means, an angular frequency included in an excitation current command signal generated from the sine wave generating means, a secondary magnetic flux obtained by the amplitude value detecting means, and an amplitude value of the current information Or based on the phase difference between the secondary flux and the current information obtained by said phase difference detecting means, it is characterized in that a constant computing means for obtaining a motor electric constants.

According to the invention described in claim 1, the secondary resistance value can be obtained, and according to the invention described in claim 2, the secondary circuit time constant can be obtained. According to the invention described in claim 3, In accordance with the invention according to claim 4, since the offset compensation of the integration means of the voltage model magnetic flux calculation means can be compensated, the measurement accuracy of the motor electrical constant can be increased, According to the fifth and sixth aspects of the invention, the measurement accuracy of the secondary resistance can be increased, and according to the seventh aspect of the invention, the saturation characteristic of the exciting inductance can be obtained. According to the invention, the exciting inductance can be obtained by a method different from that of the third aspect. According to the invention of claim 9, the motor electrical constant can be obtained.
As a result, the motor electrical constant can be obtained with high accuracy, and there is an effect of improving the control accuracy such as static / dynamic characteristics in the inverter control device of the induction motor.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 3 is a block diagram of an inverter control apparatus for an induction motor to which the present invention is applied. In the figure, 1 is an induction motor, 2 is a voltage source inverter (2-1 is a converter unit, 2-2 is an inverter unit) that drives the induction motor 1, and 3 is a PWM calculation unit, which is a primary voltage command Vu * in a fixed coordinate system. , Vv *, Vw * to generate a PWM pulse pattern.
4 is a base circuit, 5 is a current detector for detecting an inverter output current, 6 is a speed detector attached to the induction motor, 7 is a speed calculation unit, and a detection speed ωr of the induction motor 1 from a detection pulse of the speed detector 6. Is generated.
8 is a coordinate conversion unit that uses a magnetic flux command phase θ, which will be described later, to convert the detected current into a three-phase / two-phase conversion into a rotation coordinate dq axis component (Id: excitation current, Iq: torque current), Reference numerals 9 and 10 denote subtractors that match the excitation current command Id * and the detection Id to obtain the excitation current deviation ΔId, and match the torque current command Iq * and the detection Iq to obtain the torque current deviation ΔIq. Reference numeral 11 denotes an excitation current control unit (ACRd) that determines a voltage command Vd * in the direction of excitation current from the excitation current deviation ΔId, and reference numeral 12 denotes a torque current control unit (ACRq) that determines a voltage command Vq * in the direction of torque current from the torque current deviation ΔId. . Reference numeral 13 denotes a coordinate conversion unit, which uses a magnetic flux command phase θ, which will be described later, from the voltage command Vd * in the excitation current direction and the voltage command Vq * in the torque current direction, and the primary voltage commands Vu *, Vv *, Vw * in the fixed coordinate system. Ask for.
In the coordinate conversion units 8 and 13, the calculations of the formulas (1) and (2) are performed, respectively.

  Reference numeral 14 denotes a magnetic flux command calculation unit, 15 denotes a slip frequency calculation unit, 16 denotes an adder, and the magnetic flux command calculation unit 14 adds the detected speed ωr and a slip frequency command ωs * which is an output value of the slip frequency calculation unit 15. The primary frequency command ω1 * added using 16 is input and the magnetic flux command φ * is output. Reference numeral 17 denotes a coefficient unit that obtains an excitation current command Id * from the φ *. An integrator 18 integrates the primary frequency command ω1 * to obtain a magnetic flux command phase θ.

FIG. 1 is a block diagram of an inverter control device for an induction motor during operation of the present invention. In the figure, 20 is a sine wave generating means and 21 is a motor constant measuring means. The sine wave generating means 20 outputs a signal including a sine wave component, and the output signal becomes an excitation current command Id *. The magnetic flux command phase θ and the torque current command Iq * are fixed to 0, and the Vα * and Iα signals are output from the coordinate conversion units 8 and 13 and input to the motor constant measuring means 21.
With these configurations and the above formulas (1) and (2), the electric motor 1 can maintain a stopped state, and Iα and Vα * are signals based on the output signal of the sine wave generating means 20, and Iβ = Iq * = 0, Vβ It can be seen that * = Vq * = 0.

  FIG. 2 is a block diagram of the motor constant measuring means 21. In the figure, 22-1 and 22-2 are division means, 23 is multiplication means, 24 is a tangent (tan) calculation means, 30 is a voltage model type magnetic flux calculation means, 40 is a current model type magnetic flux calculation means, 50-1, 50-2 is an amplitude value detecting means, 60 is a phase difference detecting means, 70 is an offset compensating means, 80 is an R2 correcting means, and the motor constant measuring means 21 receives the sine wave signal output from the sine wave generating means 20. Angular frequency values ω1, ω2 and timer information are input.

FIG. 4 is a configuration diagram of the voltage model type magnetic flux calculation means 30. In the figure, 31 is an integrating means, 32 and 33 are primary voltage drop calculating means, 32 is a primary resistance R 1, 33 is a leakage inductance, and 34-1 and 34-2 are subtracting means.
With this configuration, the secondary magnetic flux φαV is calculated from the equation (3) based on the voltage equation of the induction motor.

FIG. 5 is a configuration diagram of the current model type magnetic flux calculation means 40. FIG. 5 shows the detection speed ωr = 0 because the motor is stopped. In the figure, 41 is an integrating means, 42 and 43 are coefficient multipliers, 42 is a secondary circuit time constant T2, 43 is a value of the secondary resistance R2, and 44 is a subtracting means.
With this configuration, the secondary magnetic flux φαI is calculated from the equation (4) based on the current equation of the induction motor.

FIG. 6 is a block diagram of the amplitude value detecting means 50-1. In the figure, 51 is a maximum value selection means, 52 is a minimum value detection means, 53-1, 53-2 are delay means, and 54 is a subtractor.
With this configuration, the amplitude value is detected as the difference between the maximum value max (Iα) and the minimum value min (Iα) of Iα that is the input signal.
| Iα | _peak = max (Iα) −min (Iα) (5)

FIG. 7 is a configuration diagram of the phase difference detection means 60. In the figure, 61-1 and 61-2 are maximum value detection means, 62-1 to 62-6 are delay means, 63-1 and 63-1 are latch means, and 64-1 and 64-2 are maximum value selection means. , 65 is a subtracting means, and 66 is a multiplying means.
The maximum value detecting means 61-1 is a circuit that outputs a trigger signal when U1 <U2 and U2> U3 are satisfied when three consecutive Iα signals are U1, U2, and U3.
With this configuration, the phase difference between the Iα signal and the φαV signal is obtained by the product of the time difference (t2−t1) at which the Iα signal and the φαV signal are maximum values and the angular frequency value ω of the sine wave signal commanded at this time. δ is measured.
δ = (t2−t1) × ω (6)

Prior to detailed description of the embodiment, the basic concept of measurement by the motor constant measuring means 21 shown in FIG. 2 will be described.
Now, from the above equation (4), the secondary magnetic flux φαI based on the current equation of the induction motor is represented by a transfer function of a primary delay element G (s) = M / (1 + T2 · p) if the input signal Iα is used. .
At this time, as is well known, the output amplitude ratio | G | and delayed phase angle ∠G when a sine wave signal having an angular frequency of ω is input are obtained by the following equations.

  Here, when ω is selected so that ω · T2 is sufficiently large with respect to 1 (hereinafter referred to as ω1),

It becomes.
Therefore, since ω1 is known, the secondary resistance R2 is obtained by the following equation.

  Next, when ω is selected so that 1 and ω · T2 are substantially equal (hereinafter referred to as ω2),

It becomes. From the equations (9) and (10), the excitation inductance M is obtained by the following equation.

Examples will be described below.
Each of the angular frequency value ω1 included in the excitation current command signal generated from the sine wave generating means 20, the voltage model type secondary magnetic flux obtained by the amplitude value detecting means 50-1 and 50-2, and the amplitude value of the current information. An operation for obtaining the secondary resistance value R2 based on the maximum value will be described.
Since the voltage model type magnetic flux calculating means 30 and the current model type magnetic flux calculating means 40 output coincide with each other and the current model expression can be expressed as G _I (s) = M / (1 + T 2 · p), the voltage shown in FIG. If the model type magnetic flux calculation means 30 is used and the circuit of FIG. 1 is operated, the ratio of the amplitude values of φαv and Iα can be measured as | G | _ω1 from FIG. The resistance R2 can be calculated.
R2 = | φαv | _peak / | Iα | _peak × ω1 (12)

Next, based on the angular frequency value ω2 included in the excitation current command signal generated from the sine wave generating means 20 and the phase difference between the voltage model magnetic flux and current information obtained by the phase difference detecting means 60, the secondary circuit time The operation for obtaining the constant T2 will be described.
If the voltage model type magnetic flux calculating means 30 shown in FIG. 4 is used to operate the circuit of FIG. 1, the phase difference δ of φαv and Iα can be measured according to FIG. The circuit time constant T2 can be calculated.
T2 = tanδ / ω2 (13)

Next, the operation when obtaining the exciting inductance M based on the maximum values of the voltage model type magnetic flux and the amplitude value of the current information will be described.
Since the voltage model type magnetic flux calculating means 30 shown in FIG. 4 is used at ω1 and ω2, and the circuit of FIG. 1 is operated, the ratio of the amplitude values of φαv and Iα can be measured from FIG. The exciting inductance M can be calculated from the equation by the following equation.

  This can also be calculated as follows using the secondary resistance R2.

  Next, the offset compensation of the voltage model type magnetic flux calculation means 30 and the operation when the current model type magnetic flux calculation means 40 corrects R2 will be described.

FIG. 8 is a configuration diagram of the voltage model type magnetic flux calculation means 30 and the current model type magnetic flux calculation means 40 and the compensation means 70 and the R2 correction means 80 for compensating each output value to coincide with each other. In the figure, 71 is a subtracting means, 72 is an integrating means, 73 is a coefficient unit, 81-1 and 81-2 are absolute value converting means, 82 is a subtracting means, 83 is an integrating means, and 84 is a coefficient unit.
The subtracting means 71 outputs the deviation Δφ of the voltage model type magnetic flux calculating means 30 and the current model type magnetic flux calculating means 40 to the integrating means 72, integrates the deviation Δφ by the integrating means 72, and after the coefficient (k1) is multiplied by the coefficient unit 73. Then, the voltage model type magnetic flux calculation means 30 returns to the previous stage of the integration means 31.
The absolute value converting means 81-1 and 81-2 take the absolute values of the output values of the voltage model magnetic flux calculating means 30 and the current model magnetic flux calculating means 40, respectively, and the subtracting means 82 is the deviation Δ of the absolute value signal. | Φ | is output to the integrating means 83, the deviation Δ | φ | is integrated by the integrating means 83, multiplied by a coefficient (k2) by the coefficient multiplier 84, and then the coefficient unit 43 in the current model type magnetic flux calculating means 40 is corrected. . Although not shown, this correction is performed as R2 × (1 + k) by adding an adding unit and a multiplying unit. Note that k corresponds to the output of the coefficient unit 84, and R2 corresponds to the coefficient unit 43.
As shown in FIG. 8, the secondary resistance R2 and the secondary circuit time constant T2 obtained so far are set in the current model type magnetic flux calculating means 40, and the offset compensation of the voltage model type magnetic flux calculating means 30 and the current model type magnetic flux calculation are performed. The reason why the secondary magnetic fluxes calculated by the means 40 do not coincide is considered to be because each calculation means has an error component.
As an error component, the voltage model type magnetic flux calculating means 30 is an offset of the input signal, and the current model magnetic flux calculating means 40 is a measurement error of the secondary resistance R2.
In the offset compensation, the integration time given by the integration means 72 and the coefficient unit 73 is averaged by taking it sufficiently long with respect to the period (1 / ω2) of the sine wave component of the signal output from the sine wave generation means 20. In the correction process of R2, the integration time given by the integration means 83 and the coefficient unit 84 is the period of the sine wave component of the signal output from the sine wave generation means 20 (1 / ω 2) so as not to interfere with the offset compensation. ) In contrast to this.
Further, the actual correction process of the secondary resistance R2 is calculated by the following equation using the output K of the coefficient unit 84 and obtained as R ′.

  The exciting inductance M may be obtained by calculation from R2 and T2 as shown in equation (15) instead of equations (14) and (14) '.

When the offset compensation process and the R2 correction process described above are performed, the voltage model type magnetic flux calculation value and the current model type magnetic flux calculation value coincide with each other with high accuracy, so that the accuracy of the offset compensation is improved. Therefore, the use of the voltage model type magnetic flux calculation means 30 with offset compensation with high accuracy further brings about a virtuous cycle in which the measurement accuracy of the secondary resistance R2 increases.
If the offset compensation and the R2 correction process described above are repeated until the correction ratio (R2 ′ / R2) of the secondary resistance R2 falls within a predetermined value range, the secondary resistance R2 and the excitation inductance of the induction motor with high accuracy can be obtained. M can be obtained.

Next, the operation for obtaining the saturation characteristic of the excitation inductance M will be described. The procedure of this operation will be described in order.
(1) Based on the base voltage Vbase and base frequency fbase of the induction motor to be measured as advance preparation, the excitation current (no-load current) Im0 is calculated by the following equation.

Note that the base voltage and base frequency information are normally stored in the inverter control device, but if they are not present, they are input from an operator (not shown) attached to the inverter device.
(2) The measurement point of the saturation characteristic of the excitation inductance M is determined. The excitation current value to be obtained as a coefficient or a function is determined.
Here, description will be made with respect to Im0 in the equation (16) as points of 50%, 75%, and 100%.
(3) Next, the secondary resistance R2 and the secondary circuit time constant T2 obtained so far are set in the current model type magnetic flux calculation means 40, and the excitation current command signal generated from the sine wave generation means 20 (for example, The angular frequency value ω2) is given by the equation (17) so as to include the DC amount, the phase difference δ of φαv and Iα is measured by the circuit shown in FIG. 7, and the secondary circuit time constant T21 is obtained by the equation (13). Calculate.
Id * = A · sinω2t + Im0 × 0.5 (17)
The amplitude A is set to a small value within a range in which the maximum value selection means 64-1 and 64-2 in FIG. 7 can measure the maximum value.
(4) The operation of (3) is performed with a DC amount of 75% and 100%, and T2 2 and T2 3 are calculated.
(5) Using the measured T21, T22, and T23, the excitation inductance M under the conditions is calculated.
M1 = R2 × T21
M2 = R2 × T22
M3 = R2 × T23
As described above, the saturation characteristics of the excitation inductance M can be measured.

  Off-line tuning of motor electrical constants can be performed while the motor is stopped, so even if you do not have a speed sensor, you can move the motor in a vertical direction with a brake, such as a machine that has already been equipped with an electric motor or elevator / crane applications. It can be applied to machines that are expected to have control accuracy such as static and dynamic characteristics.

Block diagram of an inverter control device for an induction motor during operation of the present invention Block diagram of motor constant measuring means 21 The block diagram of the inverter control apparatus of the induction motor to which the present invention is applied Configuration diagram of voltage model type magnetic flux calculation means Configuration diagram of current model type magnetic flux calculation means Configuration diagram of amplitude value detection means Configuration diagram of phase difference detection means Configuration diagram of offset compensation means and R2 correction means

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Induction motor 2 Voltage type inverter 2-1 Converter part 2-2 Inverter part 3 PWM calculating part 4 Base circuit 5 Current detector 6 Speed detector 7 Speed calculating part 8, 13 Coordinate conversion part 9, 10 Subtraction means 11 Excitation current Control unit (ACRd)
12 Torque current controller (ACRq)
14 Magnetic flux command calculation unit 15 Slip frequency calculation unit 16 Addition means 17, 42, 43, 73, 84 Coefficient units 18, 31, 41, 72, 83 Integration means 20 Sine wave generation means 21 Motor constant measurement means 22-1, 22 -2 Division means 23, 66 Multiplication means 24 Tangent (tan) calculation means 30 Voltage model type magnetic flux calculation means 32, 33 Primary voltage drop calculation means 34-1, 34-2, 44, 54, 65, 71, 82 Subtraction Means 40 Current model type magnetic flux calculating means 50-1, 50-2 Amplitude value detecting means 51, 64-1, 64-2 Maximum value selecting means 52 Minimum value detecting means 53-1, 53-2, 62-1 to 62 -6 Delay means 60 Phase difference detection means 61-1 and 61-2 Maximum value detection means 63-1 and 63-1 Latch means
70 Offset compensation means 80 R2 correction means 81-1 and 81-2 Absolute value making means

Claims (9)

Coordinate conversion means for obtaining a biaxial component value on a fixed coordinate system for each of the voltage information and current information of the induction motor;
Voltage model type magnetic flux calculating means including an integrating means for performing compensation of primary resistance and leakage inductance and calculating the secondary magnetic flux of the motor using the voltage information;
Sine wave generating means for commanding an exciting current including a sine wave component so that an alternating magnetic flux is generated;
Providing an output signal of the voltage model type magnetic flux calculating means and an amplitude value detecting means for detecting each amplitude value of the current information on a fixed coordinate system;
Based on the angular frequency included in the excitation current command signal generated from the sine wave generation means, the secondary magnetic flux obtained by the amplitude value detection means, and the maximum value of the amplitude value of the current information, the secondary resistance value is determined. An inverter control device for an induction motor, characterized in that it is obtained. Coordinate conversion means for obtaining a biaxial component value on a fixed coordinate system for each of the voltage information and current information of the induction motor;
Voltage model type magnetic flux calculating means including an integrating means for performing compensation of primary resistance and leakage inductance and calculating the secondary magnetic flux of the motor using the voltage information;
Sine wave generating means for commanding an exciting current including a sine wave component so that an alternating magnetic flux is generated;
The voltage model magnetic flux calculation means output signal and the phase difference detection means of the current information on a fixed coordinate system,
Obtaining a secondary circuit time constant based on the angular frequency included in the excitation current command signal generated from the sine wave generating means and the phase difference between the secondary magnetic flux obtained by the phase difference detecting means and the current information; Inverter control device for induction motor, which is a feature. Coordinate conversion means for obtaining a biaxial component value on a fixed coordinate system for each of the voltage information and current information of the induction motor;
Voltage model type magnetic flux calculating means including an integrating means for performing compensation of primary resistance and leakage inductance and calculating the secondary magnetic flux of the motor using the voltage information;
Sine wave generating means for commanding an exciting current including a sine wave component so that an alternating magnetic flux is generated;
The voltage model magnetic flux calculation means output signal and the phase difference detection means of the current information on a fixed coordinate system,
An excitation inductance is obtained based on the angular frequency included in the excitation current command signal generated from the sine wave generation means, the secondary magnetic flux obtained by the amplitude value detection means, and the maximum value of the amplitude value of the current information. An induction motor inverter control device characterized by the above. A current model type magnetic flux calculating means including a primary delay element that sets the secondary resistance, exciting inductance, and secondary circuit time constant obtained in claims 1 to 3 and calculates the secondary magnetic flux of the motor using the current information. When,
Compensating means for compensating so that the output values of the current model magnetic flux calculating means and the voltage model magnetic flux calculating means match,
An inverter control apparatus for an induction motor, wherein offset compensation of an integration means of the voltage model type magnetic flux calculation means is performed. A current model type magnetic flux calculating means including a primary delay element that sets the secondary resistance, exciting inductance, and secondary circuit time constant obtained in claims 1 to 3 and calculates the secondary magnetic flux of the motor using the current information. When,
Compensating means for compensating so that the output values of the current model magnetic flux calculating means and the voltage model magnetic flux calculating means match,
An inverter control apparatus for an induction motor, wherein a secondary resistance is corrected and calculated.   6. The inverter control apparatus for an induction motor according to claim 5, wherein the correction process is repeated until the calculated value ratio before and after the correction of the secondary resistance becomes a predetermined value or less.   The excitation current command signal generated from the sine wave generation means includes a DC signal so that a phase difference is obtained by the phase difference detection means, and a saturation characteristic of the excitation inductance is obtained based on the phase difference. Item 3. An inverter control device for an induction motor according to Item 2.   An inverter control apparatus for an induction motor, wherein an excitation inductance is obtained from the secondary resistance and secondary circuit time constant obtained from claims 1, 2, 5, and 6. Coordinate conversion means for obtaining a biaxial component value on a fixed coordinate system for each of the voltage information and current information of the induction motor;
Voltage model type magnetic flux calculating means including an integrating means for performing compensation of primary resistance and leakage inductance and calculating the secondary magnetic flux of the motor using the voltage information;
Sine wave generating means for commanding an exciting current including a sine wave component so that an alternating magnetic flux is generated;
Providing an output signal of the voltage model type magnetic flux calculating means and an amplitude value detecting means for detecting each amplitude value of the current information on a fixed coordinate system;
The voltage model magnetic flux calculation means output signal and the phase difference detection means of the current information on a fixed coordinate system,
The angular frequency included in the excitation current command signal generated from the sine wave generating means, the secondary magnetic flux obtained by the amplitude value detecting means, and the maximum value of the amplitude value of the current information or the phase difference detecting means. An inverter control apparatus for an induction motor, comprising: constant calculation means for obtaining a motor electrical constant based on a phase difference between a secondary magnetic flux and the current information.