JPH07143800A - Vector control method and system for induction motor - Google Patents

Abstract

PURPOSE:To allow the determination of a speed estimated value only through multiplication and subtraction without requiring any speed detector, voltage detector, or current controller. CONSTITUTION:A torque current i1q detected from primary current is multiplied by a predetermined constant K of an induction motor at a multiplier 7 to estimate a slip angular frequency and then an estimated value LAMBDAomegas of slip angular frequency is subtracted from a slip angular frequency command value omegas* at a subtractor 8. The subtracted value >=omegas is then added at an adder 9 to a given speed command value omegar* thus determining an estimated rotational speed LAMBDAomegar of the induction motor. The estimated speed value LAMBDAomegar is subtracted from the speed command value omegar* at a subtractor 10 and a torque current command value i1q is determined based on the value LAMBDAomegar at a speed controller 11. The torque current command value i1q* is then multiplied by the constant K at a multiplier 12 to determined a slip angular frequency command value omegas* which is added at an adder 13 to the speed command value omegar* thus determined a primary frequency omega.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention determines a voltage command value for a frequency converter based on an exciting current and a torque current detected from a primary current of an induction motor, and an exciting current command value and a rotation speed command value. The present invention relates to a vector control method and a vector control device for an induction motor that controls the output frequency of the frequency converter to control the speed of the induction motor driven by the output of the frequency converter.

[0002]

2. Description of the Related Art A method of driving an induction motor by using a frequency converter such as an inverter or a cycloconverter to control the output frequency of the frequency converter to control the speed of the induction motor, has a high-speed response and high accuracy. Vector control that enables control is known. Vector control has been developed as a control method that obtains the same performance as a DC motor with a squirrel-cage induction motor. In other words, the rectification function of the DC motor is controlled electrically, and the orthogonal relationship between the excitation vector and the current vector is controlled. Is intended to control the rotation speed.

The vector control method using the frequency converter is based on slip angular frequency control and is a method for controlling the output frequency of the frequency converter according to the rotation speed of the induction motor, so that a speed detector is required. Met. Therefore,
A vector control method that does not use a speed detector that detects the primary voltage of an induction motor by using a voltage detector to calculate the magnetic flux and controls the primary current and frequency of the induction motor according to the method is described in, for example, 1984 National Electrical Society of Japan. Conference Proceedings p. 73
1, "PG-less vector control method of induction motor using slip frequency", Proceedings of 1982 National Conference of the Institute of Electrical Engineers of Japan p. 709, “Magnetic field orientation control method by vector calculation of secondary interlinkage of induction motor (vector control without TG)” and the like.

However, in the above-described vector control method that does not use the speed detector, there is a problem of iron core saturation phenomenon in the insulating transformer for detecting the primary voltage of the induction motor or drift in the integrator for calculating the magnetic flux. There is a problem that the operation is inherently impossible to obtain sufficient detection and calculation accuracy particularly at low frequency operation, and stable operation cannot be performed.

Therefore, as a vector control method further improving the above points, the primary current of the induction motor is detected, the detected primary current is converted into a rotating coordinate system to obtain the torque current and the exciting current, and the induction motor is obtained. A vector control method for an induction motor which does not use a speed detector and a voltage detector for calculating an estimated value of the rotational speed of the motor and performing speed control is proposed in, for example, Japanese Patent Publication No. 3-44509 or Japanese Patent Laid-Open No. 262887. There is.

[0006]

However, in Japanese Patent Publication No. 3-44509, the torque current is calculated by making the difference between the rotation speed command and the estimated value of the rotation speed zero in the calculation for determining the primary frequency. Since the primary frequency is determined by calculating the command value and making the difference between the torque current command and the torque current detected from the primary current of the induction motor zero, that is, the speed control calculation and the current control calculation are performed. Therefore, there is a problem that the control calculation becomes complicated.

Further, in the method disclosed in Japanese Patent Laid-Open No. 2-262887, no countermeasure is taken against the characteristic change when the constant of the induction motor handled in the control calculation is different from the actual induction motor, and the accuracy of the estimated speed is sufficient. There was a problem that could not be obtained. The present invention has been made in view of the above points, and an object of the inventions of claims 1 to 4 is to provide a vector control method for an induction motor and a device thereof that do not use a speed detector or a voltage detector. The present invention provides a vector control method for an induction motor and a device for the same, in which control calculation is simplified.

It is an object of the invention of claims 5 to 8 to provide a vector control method for an induction motor which does not use a speed detector or a voltage detector, and an apparatus therefor, in which a primary frequency caused by a sudden change in a speed command value is used. There is provided a vector control method and an apparatus therefor capable of preventing a rapid change in the current and preventing an overcurrent due to a slip angular frequency problem. Claim 9
It is an object of the invention of claim 11 to provide a vector control method for an induction motor and a device thereof that do not use a speed detector or a voltage detector, and provide a vector control method for an induction motor and a device thereof that simplify control calculation. To provide.

It is an object of the inventions of claims 12 to 15 to provide a vector control method for an induction motor and a device thereof which do not use a speed detector or a voltage detector. (EN) A vector control method for an induction motor and a device therefor capable of suppressing the above. It is an object of the inventions of claims 16 and 17 to improve a speed response characteristic when a load is applied in a vector control method for an induction motor and a device thereof which do not use a speed detector or a voltage detector. A vector control method for an induction motor and a device therefor are provided.

The object of the invention of claims 18 to 23 is to provide a vector control method and apparatus for an induction motor which does not use a speed detector or a voltage detector, even when the rotation speed of the induction motor becomes high. (EN) It is possible to provide a vector control method of an induction motor and a device thereof which are stable and have good speed response characteristics. It is an object of the inventions of claims 24 and 25 to provide a vector control method for an induction motor and a device therefor, which do not use a speed detector or a voltage detector, regardless of the rotational speed or load of the induction motor. Another object of the present invention is to provide a vector control method of an induction motor and an apparatus thereof that can prevent the output voltage from being saturated and prevent a control malfunction.

The object of the invention of claim 26 and claim 28 is to provide a vector control method for an induction motor which does not use a speed detector or a voltage detector, and an apparatus therefor, which can prevent deterioration of speed accuracy. An object is to provide a vector control method of an electric motor and an apparatus thereof. The purpose of the invention of claim 27 is that in the invention of claim 26,
Another object of the present invention is to provide a vector control method for an induction motor that can prevent vibration of the rotation speed.

[0012]

In order to achieve the above-mentioned object, in the invention of claim 1, the induction motor is driven by a voltage source inverter, and the voltage source is converted from the excitation voltage component and the torque component voltage of the induction motor. Along with obtaining the command voltage value of the inverter, the torque current and exciting current detected from the primary current of the induction motor, and the primary frequency and the voltage are controlled by these command values are used in the vector controller of the induction motor, Estimate the slip angular frequency by multiplying the torque current by a predetermined constant in the induction motor, subtract the estimated value of the slip angular frequency from the slip angular frequency command value, and add the subtracted value to the given speed command value. Then, the estimated value of the rotational speed of the induction motor is obtained, and the torque current command value is obtained based on the difference between the estimated speed value and the speed command value. The command value is multiplied by a constant obtained from the constant of the induction motor to obtain the slip angular frequency command value, and the slip angular frequency command value and the speed command value are added to obtain the primary frequency. To do.

According to a second aspect of the present invention, the induction motor is driven by the voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage and the torque component voltage of the induction motor, and the primary current of the induction motor is obtained. In the vector control device of the induction motor in which the primary frequency and the voltage are controlled by the torque current and the exciting current detected from the above, and their command values, the detection means for detecting the torque current from the primary current, and the detection means Estimating means for estimating the slip angular frequency by multiplying the torque current value obtained by the induction motor with a predetermined constant, and subtracting means for subtracting the estimated value of the slip angular frequency obtained by the estimating means from the slip angular frequency command value. Then, the subtraction value obtained by the subtraction means and the given speed command value are added to obtain an estimated value of the rotation speed of the induction motor. A first adding means, a means for obtaining a torque current command value based on the difference between the speed estimated value obtained by the first adding means and the speed command value, and a torque current command value obtained by this means. Multiplying the constant obtained from the constant of the induction motor to obtain the slip angular frequency command value, and the slip angular frequency command value obtained by this multiplying means and the speed command value are added to obtain the primary frequency. And a second adding means for obtaining.

According to a third aspect of the present invention, the induction motor is driven by the voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage and the torque component voltage of the induction motor, and the primary current of the induction motor is obtained. Used in the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the torque current and the exciting current detected from these and the command values, the torque current detected from the primary current is subtracted from the torque current command, This subtraction value is multiplied by a constant determined in advance by the induction motor, and the multiplication value is added to the given speed command value to obtain an estimated value of the rotation speed of the induction motor, and the estimated speed value and the speed command value are The torque current command value is calculated based on the difference, and this torque current command value is multiplied by the constant calculated from the constants of the induction motor to determine the slip angular frequency. Seeking decree value, and obtains a primary frequency by adding the the slip angular frequency command and the speed command value.

According to another aspect of the present invention, the induction motor is driven by the voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage component and the torque component voltage of the induction motor, and the primary current of the induction motor is obtained. In the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the torque current and the exciting current detected from the primary current and the command value thereof, the detection means that detects the torque current from the primary current, and the detection means Means for subtracting the torque current value from the torque current command value, multiplication means for multiplying the subtraction value obtained by the subtraction means by a constant determined in advance by the induction motor, and a speed command given the multiplication value of the multiplication means. A first addition means for adding to the value to obtain an estimated value of the rotation speed of the induction motor, and a speed estimated value obtained by the first addition means A means for obtaining the torque current command value based on the difference from the speed command value, and a slip angular frequency command value by multiplying the torque current command value obtained by this means by a constant obtained from the constant of the induction motor. It is provided with a multiplying means for obtaining, and a second adding means for obtaining the primary frequency by adding the slip angular frequency instruction obtained by the multiplying means and the speed instruction value.

According to a fifth aspect of the present invention, the induction motor is driven by a voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage component and the torque component voltage of the induction motor, and the primary current of the induction motor is obtained. Used in a vector controller of an induction motor in which the primary frequency and the voltage are controlled by the torque current and exciting current detected from the above, and their command values, and the torque current is multiplied by a constant determined in advance by the induction motor to cause slippage. Estimate the angular frequency, subtract the estimated value of the slip angular frequency from the slip angular frequency command value, add the subtracted value to the given speed command value to obtain the estimated value of the rotational speed of the induction motor, A torque current command value was calculated based on the difference between the estimated value and the speed command value, and this torque current command value was calculated from the constant of the induction motor. Seeking the slip angular frequency command value by multiplying the number, and obtains a primary frequency by adding the the slip angular frequency command value and the speed estimated value.

According to a sixth aspect of the present invention, the induction motor is driven by a voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage component and the torque component voltage of the induction motor, and the primary current of the induction motor is also obtained. In the vector control device of the induction motor in which the primary frequency and the voltage are controlled by the torque current and the exciting current detected from the primary current and the command value thereof, the detection means for detecting the torque current from the primary current, and the detection means Estimating means for estimating the slip angular frequency by multiplying the torque current value to a constant determined in advance by the induction motor, and subtraction for subtracting the estimated value of the slip angular frequency obtained by the estimating means from the slip angular frequency command value. Means and the subtraction value obtained by the subtraction means and the given speed command value are added to obtain an estimated value of the rotational speed of the induction motor. A first adding means, a means for obtaining a torque current command value based on the difference between the speed estimated value obtained by the first adding means and the speed command value, and a torque current command value obtained by this means. Is multiplied by a constant obtained from the constant of the induction motor to obtain the slip angular frequency command value, and the slip angular frequency command value obtained by the multiplying means and the speed estimated value are added to obtain the primary frequency. And a second adding means for obtaining

According to a seventh aspect of the present invention, the induction motor is driven by a voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage and the torque component voltage of the induction motor, and the primary current of the induction motor is obtained. It is used in a vector controller of an induction motor in which the primary frequency and the voltage are controlled by the torque current and the exciting current detected from the above, and their command values, and the torque current detected from the primary current is preset in the induction motor. Estimate the slip angular frequency by multiplying by the constant, subtract the estimated value of the slip angular frequency from the slip angular frequency command value, and add the subtracted value to the given speed command value to estimate the rotational speed of the induction motor. Value, the torque current command value is calculated based on the difference between the estimated speed value and the speed command value, and the induction motor is set to this torque current command value. The slip angular frequency command value is obtained by multiplying the constant obtained from the constant of, and the slip angular frequency command and the slip angular frequency estimated value are added values obtained by adding the slip angular frequency command value and the speed command value. It is characterized in that the primary frequency is obtained by adding the deviation of.

According to another aspect of the present invention, the induction motor is driven by the voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage and the torque component voltage of the induction motor, and the primary current of the induction motor is obtained. In the vector control device of the induction motor in which the primary frequency and the voltage are controlled by the torque current and the exciting current detected from the primary current and the command value thereof, the detection means for detecting the torque current from the primary current, and the detection means Estimating means for estimating the slip angular frequency by multiplying the torque current value to a constant determined in advance by the induction motor, and subtraction for subtracting the estimated value of the slip angular frequency obtained by the estimating means from the slip angular frequency command value. Means and the subtraction value obtained by the subtraction means and the given speed command value are added to obtain an estimated value of the rotational speed of the induction motor. A first adding means, a means for obtaining a torque current command value based on the difference between the speed estimated value obtained by the first adding means and the speed command value, and a torque current command value obtained by this means. A multiplication means for multiplying a constant obtained from the constant of the induction motor to obtain the slip angular frequency command value; and a second means for adding the slip angular frequency command value and the speed command value obtained by the multiplying means. Means for obtaining the deviation between the slip angular frequency command value and the slip angular frequency estimated value, and the deviation value obtained by this means is added to the value obtained by the second adding means to obtain the primary frequency. It is characterized in that it is provided with a means for obtaining.

According to a ninth aspect of the present invention, the induction motor is driven by the voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage and the torque component voltage of the induction motor, and the primary current of the induction motor is obtained. It is used in the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the torque current and the exciting current detected from the above, and their command values, and the torque current is delayed by a predetermined value in the induction motor. It is characterized in that the primary frequency is obtained by multiplying this constant by multiplying the constant by multiplying it by a constant.

According to a tenth aspect of the invention, in the ninth aspect, the delay value of the torque current is changed based on the difference between the torque current value and the delay value of the torque current.
According to the invention of claim 11, The induction motor is driven by a voltage source inverter, and the command voltage value of the voltage source inverter is obtained from the excitation voltage component and the torque component voltage of the induction motor, and the torque current and the excitation current detected from the primary current of the induction motor are In the vector controller of the induction motor in which the primary frequency and the voltage are controlled by these command values, the detection means for detecting the torque current from the primary current, the means for delaying the detected torque current, and the delay by this means. Multiplying means for multiplying the delay value of the torque current obtained by this by a constant determined in advance by the induction motor, and means for obtaining the primary frequency by adding the multiplied value obtained by this multiplying means and the given speed command value. It is characterized by having.

According to the twelfth aspect of the present invention, the induction motor is driven by the voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage and the torque component voltage of the induction motor, and the primary current of the induction motor is obtained. The exciting current and exciting current command value detected from the primary current of the induction motor used in the vector controller of the induction motor in which the primary frequency and the above voltage are controlled by the torque current and exciting current detected from The exciting current command value is corrected so as to eliminate the difference between

In the thirteenth aspect of the present invention, the induction motor is driven by the voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage and the torque component voltage of the induction motor, and the primary current of the induction motor is obtained. Used in the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the torque current and the exciting current detected from these and the command values thereof, and the initial setting value of the primary resistance of the induction motor and the initial value of the exciting current command value Correction of the primary resistance of the induction motor that makes the difference between the excitation current detected from the primary current of the induction motor and the excitation current command zero when the command value is externally applied and the induction motor is stopped and only the excitation current is supplied. Calculate the value and add this correction value to the initial setting value of the primary resistance to obtain the setting value of the primary resistance. Calculate the correction value of the excitation current command value that makes the difference between the excitation current detected from the primary current of the motor and the excitation current command zero, and subtract the correction value from the initial command value of the excitation current command value to obtain the excitation current. The feature is that the command value is obtained.

According to a fourteenth aspect of the present invention, the induction motor is driven by a voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage and the torque component voltage of the induction motor, and the primary current of the induction motor is obtained. Used in the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the torque current and the exciting current detected from these and the command values thereof, and the initial setting value of the primary resistance of the induction motor and the initial value of the exciting current command value Correction of the primary resistance of the induction motor that makes the difference between the excitation current detected from the primary current of the induction motor and the excitation current command zero when the command value is externally applied and the induction motor is stopped and only the excitation current is supplied. Calculate the value and add this correction value to the initial setting value of the primary resistance to obtain the setting value of the primary resistance. Calculate the correction value of the excitation current command value that makes the difference between the excitation current detected from the primary current of the motor and the excitation current command zero, and subtract the correction value from the initial command value of the excitation current command value to obtain the excitation current. It is characterized in that a command value is obtained, and after correcting the exciting current command value, the set value of the primary resistance is corrected.

According to a fifteenth aspect of the present invention, in the twelfth to fourteenth aspects of the invention, an initial setting value of the secondary resistance of the induction motor is externally applied, and the primary current of the induction motor is rotated while the induction motor is rotated. Calculate the correction value for the excitation current command value that makes the difference between the excitation current detected from and the excitation current command zero, and then calculate the correction value for the secondary resistance of the induction motor from this correction value. Is added to the initial set value of to obtain the set value of the secondary resistance.

According to the sixteenth aspect of the present invention, the induction motor is driven by the voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage and the torque component voltage of the induction motor, and the primary current of the induction motor is obtained. Used in the vector control device of the induction motor in which the primary frequency and the voltage are controlled by the torque current and the exciting current detected from the above, and the command values thereof, the detection means for detecting the torque current from the primary current, and the primary resistance Calculate the excitation voltage from the multiplication value obtained by multiplying the set value and the excitation current command value, and the value obtained by multiplying the set value of the torque current and the equivalent leakage inductor value by the above primary frequency. , The magnetic flux obtained by multiplying the product value obtained by multiplying the set value of the primary resistance by the torque current, and the set value of the primary inductor by the excitation current command value. The torque voltage is calculated from the command value and the product value obtained by multiplying the primary frequency, and the torque current used to calculate the excitation voltage is the torque current command value, and the torque used to calculate the torque voltage. The current is a torque current detection value or a delay value thereof.

In the seventeenth aspect of the present invention, the induction motor is driven by the voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage component and the torque component voltage of the induction motor, and the primary current of the induction motor is obtained. In a vector controller for an induction motor, in which the primary frequency and the voltage are controlled by the torque current and the exciting current detected from the above, and their command values, a first multiplication for multiplying the set value of the primary resistance by the exciting current command value. Means, a second multiplication means for multiplying the set value of the torque current, the equivalent leakage inductor value and the primary frequency, and a first calculation for obtaining an excitation voltage from the multiplication values of the first and second multiplication means. Means, third multiplying means for multiplying the set value of the primary resistance and the torque current, and the magnetic flux command value by multiplying the set value of the primary inductor and the exciting current command value. The fourth multiplication means to be obtained, the fifth multiplication means for multiplying the magnetic flux command value obtained by the fourth multiplication means and the primary frequency, and the torque divided voltage from the multiplication values of the third and fifth multiplication means. And a second calculation means for obtaining
The torque current used to calculate the excitation voltage component is the torque current command value, and the torque current used to calculate the torque component voltage is the torque current detection value or its delay value.

In the eighteenth aspect of the present invention, the induction motor is driven by the voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage component and the torque component voltage of the induction motor, and the primary current of the induction motor is obtained. Used in the vector controller of the induction motor in which the primary frequency and the above voltage are controlled by the torque current and exciting current detected from the above, and their command values, and is obtained by multiplying the set value of the primary resistance and the exciting current command value. The excitation component voltage is obtained from the obtained multiplication value, the value obtained by multiplying the setting value of the torque current and the equivalent leakage inductor value, and the primary frequency, and the setting value of the primary resistance is multiplied by the torque current. Multiplication obtained by multiplying the magnetic flux command value obtained by multiplying the set value of the primary inductors and the exciting current command value by the primary frequency Then, the torque component voltage is obtained from the torque current detected from the primary current and the torque frequency used in the calculation of the torque component voltage according to the primary frequency and the torque current command value and the torque current detection value or its delay value. It is characterized by switching to.

According to a nineteenth aspect of the invention, in the seventeenth aspect of the invention, when the primary frequency is a low frequency, the torque current used for the torque component voltage is set as the torque current detection value or its delay value, and when it is a high frequency. , And a torque current command value. In the invention of claim 20, the induction motor is driven by the voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage component and the torque component voltage of the induction motor, and the command voltage value is detected from the primary current of the induction motor. In the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the torque current and the exciting current and their command values, the detecting means for detecting the torque current from the primary current, the set value of the primary resistance and the exciting current. First multiplication means for multiplying the command value, second multiplication means for multiplying the set value of the torque current and the equivalent leakage inductor value by the primary frequency, and multiplication values of the first and second multiplication means A first calculation means for obtaining the excitation voltage component from the third multiplication means, a third multiplication means for obtaining the excitation resistance voltage by multiplying the set value of the primary resistance by the torque current, and a set value of the primary inductors. A fourth multiplying means for obtaining a magnetic flux command value by multiplying the current command value,
Fifth multiplication means for multiplying the magnetic flux command value obtained by the fourth multiplication means and the primary frequency, and second calculation means for obtaining the torque component voltage from the multiplication values of the third and fifth multiplication means. A torque current command value and a torque current detection value or a delay value thereof for switching the torque current used to calculate the torque component voltage according to the torque current detected from the primary current and the primary frequency. It is characterized by

According to the twenty-first aspect of the invention, the induction motor is driven by the voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage and the torque component voltage of the induction motor, and the primary current of the induction motor is obtained. Used in the vector controller of the induction motor in which the primary frequency and the above voltage are controlled by the torque current and exciting current detected from the above, and their command values, and is obtained by multiplying the set value of the primary resistance and the exciting current command value. The excitation component voltage is obtained from the obtained multiplication value, the value obtained by multiplying the setting value of the torque current and the equivalent leakage inductor value, and the primary frequency, and the setting value of the primary resistance is multiplied by the torque current. Multiplication obtained by multiplying the magnetic flux command value obtained by multiplying the set value of the primary inductors and the exciting current command value by the primary frequency Determined torque portion voltage and a, in response to the primary voltage obtained from the excitation component voltage and the torque portion voltage,
It is characterized in that the torque current used for calculating the torque component voltage is switched between the torque current command value and the torque current detection value or its delay value.

According to a twenty-second aspect of the invention, in the twenty-first aspect of the invention, when the primary voltage obtained from the excitation voltage and the torque component voltage is less than a predetermined value, the torque current used for calculating the torque component voltage is set. The torque current detection value or a delay value thereof is set, and when it is equal to or larger than the predetermined value, the torque current command value is set. In the invention of claim 23, the induction motor is driven by the voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage component and the torque component voltage of the induction motor, and the command voltage value is detected from the primary current of the induction motor. In the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the torque current and the exciting current and their command values, the detecting means for detecting the torque current from the primary current, the set value of the primary resistance and the exciting current. First multiplication means for multiplying the command value, second multiplication means for multiplying the set value of the torque current and the equivalent leakage inductance value by the primary frequency, and multiplication values of the first and second multiplication means A first calculation means for obtaining an excitation voltage component from the third calculation means, a third multiplication means for obtaining a setting value of the primary resistance and a torque current, and a set value of the primary inductors. A fourth multiplying means for obtaining a magnetic flux command value by multiplying the current command value,
Fifth multiplication means for multiplying the magnetic flux command value obtained by the fourth multiplication means and the primary frequency, and second calculation means for obtaining the torque component voltage from the multiplication values of the third and fifth multiplication means. A means for switching the torque current used for the calculation of the torque component voltage between the torque current command value and the detected torque current value or its delay value according to the primary voltage obtained from the excitation voltage component and the torque component voltage. It is characterized by that.

According to the twenty-fourth aspect of the present invention, the induction motor is driven by the voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage and the torque component voltage of the induction motor, and the primary current of the induction motor is obtained. Used in the vector controller of the induction motor in which the primary frequency and the above voltage are controlled by the torque current and exciting current detected from the above, and their command values, and is obtained by multiplying the set value of the primary resistance and the exciting current command value. The obtained multiplication value, the excitation current voltage is obtained from the value obtained by multiplying the set value of the torque current command value, the equivalent leakage inductor value, and the primary frequency, and the set value of the primary resistance and the torque current are obtained. It is calculated by multiplying the multiplication value obtained by multiplying the primary inductor setting value by the magnetic flux command value obtained by multiplying the exciting current command value by the primary frequency. Determined torque portion voltage and a multiplication value,
The magnetic flux command value obtained by multiplying the set value of the primary inductance by the exciting current command is changed by the primary voltage obtained from the excitation voltage and the torque voltage.

In the twenty-fifth aspect of the present invention, the induction motor is driven by the voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage and the torque component voltage of the induction motor, and the primary current of the induction motor is obtained. In the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the torque current and the exciting current detected from the above and the command values thereof, the detection means for detecting the torque current from the primary current, and the set value of the primary resistance And a magnetizing current command value, a first multiplying means, a second multiplying means for multiplying a torque current, a set value of an equivalent leakage inductor value, and the primary frequency, and first and second multiplying means. A first calculation means for obtaining an excitation voltage from a multiplication value of, a third multiplication means for obtaining a setting value of the primary resistance and a torque current, and a primary inductor And a exciting current command value to obtain a magnetic flux command value, and a fifth multiplying means for multiplying the magnetic flux command value obtained by the fourth multiplying means and the primary frequency. By the second calculation means for obtaining the torque component voltage from the multiplication values of the third and fifth multiplication means, and the primary voltage obtained from the excitation component voltage and the torque component voltage,
A means for changing the magnetic flux command value obtained by multiplying the set value of the primary inductance and the exciting current command is provided.

In the twenty-sixth aspect of the present invention, the induction motor is driven by the voltage source inverter, the command voltage value of the voltage source inverter is obtained from the excitation voltage and the torque component voltage of the induction motor, and the primary current of the induction motor is obtained. Used in the vector controller of the induction motor in which the primary frequency and the above voltage are controlled by the torque current and exciting current detected from the above, and their command values, and is obtained by multiplying the set value of the primary resistance and the exciting current command value. The obtained multiplication value, the excitation current voltage is obtained from the value obtained by multiplying the set value of the torque current command value, the equivalent leakage inductor value, and the primary frequency, and the set value of the primary resistance and the torque current are obtained. It is calculated by multiplying the multiplication value obtained by multiplying the primary inductor setting value by the magnetic flux command value obtained by multiplying the exciting current command value by the primary frequency. Determined torque portion voltage and a multiplication value,
It is characterized in that the constant determined by the induction motor is changed according to the magnetic flux command value obtained by multiplying the set value of the primary inductor and the exciting current command value.

According to a twenty-seventh aspect of the invention, in the twenty-sixth aspect of the invention, the change in the constant determined in advance by the induction motor is moderated. According to the invention of claim 28,
The induction motor is driven by a voltage source inverter, and the command voltage value of the voltage source inverter is obtained from the excitation voltage component and the torque component voltage of the induction motor, and the torque current and the excitation current detected from the primary current of the induction motor and In the vector controller of the induction motor in which the primary frequency and the voltage are controlled by these command values, the detecting means for detecting the torque current from the primary current, and the setting value of the primary resistance and the exciting current command value are multiplied. A first multiplying means, a second multiplying means for multiplying the set value of the torque current and the equivalent leakage inductor value by the primary frequency, and an exciting voltage component obtained from the multiplied values of the first and second multiplying means. 1 calculation means,
Third multiplying means for obtaining the set value of the primary resistance and the torque current, and fourth multiplying means for obtaining the magnetic flux command value by multiplying the set value of the primary inductor and the exciting current command value. Fifth multiplication means for multiplying the magnetic flux command value obtained by the fourth multiplication means and the primary frequency, and second calculation means for obtaining the torque component voltage from the multiplication values of the third and fifth multiplication means. And a means for changing a constant determined by the induction motor according to a magnetic flux command value obtained by multiplying the set value of the primary inductor and the exciting current command value.

[0036]

According to the first and second aspects of the present invention, the slip angular frequency is estimated by multiplying the torque current by a constant determined in advance by the induction motor, and the slip angular frequency estimated value is subtracted from the slip angular frequency command value. Then, the subtraction value is added to the given speed command value to obtain an estimated value of the rotational speed of the induction motor, and a torque current command value is obtained based on the difference between the speed estimated value and the speed instruction value. The torque current command value is multiplied by a constant obtained from the constant of the induction motor to obtain the slip angular frequency command value, and the slip angular frequency command value and the speed command value are added to obtain the primary frequency. The rotation speed of the induction motor can be controlled at high speed and high accuracy without using a speed detector or voltage detector, and a current controller that requires a high-speed treatment for a minor loop with respect to the speed controller is not used. It can be configured. Further, the slip angle frequency is estimated by multiplying the torque current detected from the primary current by a constant determined by the induction motor, and the estimated value of the slip angle frequency is subtracted from the slip angle frequency command,
Since the subtraction value is subtracted from the given speed command value to obtain the estimated value of the rotation speed of the induction motor, the estimated speed value is obtained only by the multiplication and subtraction processing, and the control calculation is simplified.

According to the third and fourth aspects of the present invention, the slip angular frequency is estimated by multiplying the torque current according to the first aspect of the present invention by a constant determined in advance by the induction motor, and the estimated value of the slip angular frequency and the slip angle. Instead of the calculation for calculating the difference from the frequency command, the torque current is subtracted from the torque current command, and the difference is multiplied by a constant determined in advance by the induction motor. In other words, since the torque current and the slip angular frequency are in a proportional relationship, even if the torque current is used instead of the slip angular frequency, the speed control of the induction motor can be performed in the same manner as the invention of claim 1.

According to the fifth and sixth aspects of the present invention, the slip angular frequency is estimated by multiplying the torque current by a constant previously determined by the induction motor, and the slip angular frequency estimated value is subtracted from the slip angular frequency command value. Then, the subtraction value is added to a given speed command value to obtain an estimated value of the rotational speed of the induction motor, and a torque current command value is obtained based on the difference between the speed estimated value and the speed instruction value. The torque current command value is multiplied by a constant obtained from the constant of the induction motor to obtain the slip angular frequency command value, and the slip angular frequency command value and the speed estimated value are added to obtain the primary frequency. Since the rate of change of the rotation speed estimation value is smaller than the rate of change of the rotation speed command value, the rate of change of the primary frequency, which is the sum of the slip angle frequency command value and the speed estimation value, is also small, and the slip angle frequency Overcurrent due to an excessive can be suppressed.

According to the seventh and eighth aspects of the present invention, the slip angular frequency is estimated by multiplying the torque current by a constant determined in advance by the induction motor, and the slip angular frequency estimated value is subtracted from the slip angular frequency command value. This subtracted value is added to the given speed command value to obtain the estimated value of the rotation speed of the induction motor, and the torque current command value is obtained based on the difference between the estimated speed value and the speed command value. The slip angle frequency command value is obtained by multiplying the command value by a constant obtained from the constant of the induction motor, and the slip angular frequency command is added to the added value obtained by adding the slip angle frequency command value and the speed command value. Since the primary frequency is obtained by adding the deviation of the slip angular frequency estimated value above, the command value and detection value of the slip angular frequency of the primary current increase due to the abrupt change of the primary frequency. It will function to suppress the change in the number, and as a result, it will be possible to suppress overcurrent due to excessive slip angular frequency, and it is also possible to finely adjust the primary current waveform by adjusting the degree of primary frequency correction due to deviation. Becomes According to the ninth and eleventh aspects of the invention, the value obtained by delaying the torque current is multiplied by a constant determined in advance by the induction motor, and the product value and the speed command value given are added to obtain the primary frequency. It is possible to obtain a vector control method and device which can be configured without using a current controller and which can perform a simple control calculation, and to suppress an increase rate of the primary frequency and prevent excessive slippage.

According to a tenth aspect of the invention, in the ninth aspect of the invention, the delay value of the torque current is changed based on the difference between the torque current value and the delay value of the torque current. Therefore, it is possible to obtain a vector control method and apparatus having optimum speed control characteristics. According to the invention of claim 12, the exciting current command value is corrected so as to eliminate the difference between the exciting current detected from the primary current of the induction motor and the exciting current command value. Therefore, the inductance setting error of the induction motor is corrected, It is possible to eliminate the influence of the setting error of the inductance of the induction motor in the vector calculation and prevent the deterioration of speed accuracy. Moreover, if the ratings of the induction motor are equal, the magnetic flux is almost the same regardless of the type of the motor, and the magnetic flux Is obtained by the product of the inductance and the exciting current, the inductance setting error can be corrected by correcting the exciting current based on the error between the exciting current command value and the exciting current value.

According to a thirteenth aspect of the present invention, the initial set value of the primary resistance of the induction motor and the initial command value of the exciting current command value are given from the outside, the induction motor is stopped, and only the exciting current is supplied. Obtain the correction value of the primary resistance of the induction motor that makes the difference between the exciting current detected from the primary current and the exciting current command zero, and add this correction value to the initial setting value of the primary resistance to obtain the setting value of the primary resistance. Obtain the correction value of the exciting current command value that makes the difference between the exciting current detected from the primary current of the induction motor and the exciting current command zero in the state of rotating the induction motor, and then obtain the correction value. Since the exciting current command value is obtained by subtracting the value from the initial command value, the primary resistance and inductance set for performing vector calculation are the primary resistance and inductor of the driven induction motor. And if different, can make the set primary resistance and the correction inductance for vector operations, it is possible to prevent deterioration of the speed accuracy.

According to a fourteenth aspect of the present invention, the initial setting value of the primary resistance of the induction motor and the initial command value of the exciting current command value are given from the outside, the induction motor is stopped, and only the exciting current is supplied. Obtain the correction value of the primary resistance of the induction motor that makes the difference between the exciting current detected from the primary current and the exciting current command zero, and add this correction value to the initial setting value of the primary resistance to obtain the setting value of the primary resistance. Obtain the correction value of the exciting current command value that makes the difference between the exciting current detected from the primary current of the induction motor and the exciting current command zero in the state of rotating the induction motor, and then obtain the correction value. Calculate the excitation current command value by subtracting from the initial command value
Since the primary resistance setting value is corrected after the excitation current command value is corrected, if the primary resistance and inductance set for performing vector calculation are different from the primary resistance and inductance of the driven induction motor, the vector In addition to the function to correct the primary resistance and inductance set for calculation, the set value of the primary resistance is corrected even if the primary resistance changes due to the temperature of the induction motor to prevent deterioration of speed accuracy. be able to.

According to a fifteenth aspect of the present invention, in the twelfth to fourteenth aspects, an initial setting value of the secondary resistance of the induction motor is externally applied, and the primary current of the induction motor is rotated when the induction motor is rotated. Calculate the correction value for the excitation current command value that makes the difference between the excitation current detected from and the excitation current command zero, and then calculate the correction value for the secondary resistance of the induction motor from this correction value. Since the setting value of the secondary resistance is calculated by adding it to the initial setting value of, the setting value of the secondary resistance that changes with the change of the excitation current command value is corrected, and the slip angular frequency is estimated accordingly. By correcting the proportional constant of the induction motor used for that purpose, the deterioration of speed accuracy can be further reduced.

According to the sixteenth and seventeenth aspects of the present invention, the multiplication value obtained by multiplying the set value of the primary resistance and the exciting current command value, the set value of the torque current and the equivalent leakage inductors value, and the primary value. The excitation voltage is obtained from the value obtained by multiplying the frequency, and the multiplication value obtained by multiplying the setting value of the primary resistance and the torque current, the setting value of the primary inductors, and the excitation current command value The torque component voltage is obtained from the product value obtained by multiplying the magnetic flux command value obtained by multiplying by and the primary frequency, and the torque current used to calculate the excitation component voltage is the torque current command value, Since the torque current used to calculate the torque component voltage is the torque current detection value or its delay value, the speed response when a load torque is applied can be improved.

According to the eighteenth and twentieth aspects of the present invention, the multiplication value obtained by multiplying the set value of the primary resistance and the exciting current command value, the set value of the torque current and the equivalent leakage inductor value, and the above-mentioned primary value. The excitation voltage is obtained from the value obtained by multiplying the frequency, and the multiplication value obtained by multiplying the setting value of the primary resistance and the torque current, the setting value of the primary inductors, and the excitation current command value A torque component voltage is obtained from the multiplication value obtained by multiplying the magnetic flux command value obtained by multiplying by and the primary frequency, according to the torque current detected from the primary current and the primary frequency, Since the torque current used to calculate the torque component voltage is switched between the torque current command value and the torque current detection value or its delay value, the rotation speed is stable regardless of the set frequency, and speed response can be improved. .

According to a nineteenth aspect of the present invention, in the eighteenth aspect, when the primary frequency is a low frequency, the torque current used for the torque component voltage is the torque current detection value or its delay value, and when the primary frequency is a high frequency, Since the torque current command value is used, it is possible to suppress the vibration of the torque current when the rotation speed of the induction motor increases. Claim 21 and Claim 2
The invention of No. 3 is obtained by multiplying the multiplication value obtained by multiplying the set value of the primary resistance and the exciting current command value, the set value of the torque current and the equivalent leakage inductor value, and the above-mentioned primary frequency. The magnetic flux obtained by multiplying the set value of the primary resistance and the exciting current command value, and the product value obtained by multiplying the set value of the primary resistance by the torque current The torque component voltage is obtained from the product value obtained by multiplying the command value and the primary frequency, and the torque used to calculate the torque component voltage according to the primary voltage obtained from the excitation component voltage and the torque component voltage. Since the current is switched between the torque current command value and the torque current detection value or its delay value, the rotation speed is stable regardless of the set frequency, and the speed responsiveness is improved, like the inventions of claims 18 and 20. Can be improved That.

According to a twenty-second aspect of the present invention, in the twenty-first aspect, when the primary voltage obtained from the excitation voltage component and the torque component voltage is less than a predetermined value, the torque current used for calculating the torque component voltage is used as the torque. Since the current detection value or its delay value is used and the torque current command value is used when it is equal to or more than the predetermined value, it is possible to suppress the oscillation of the torque current when the rotation speed of the induction motor becomes high.

According to the twenty-fourth and twenty-fifth aspects of the present invention, the multiplication value obtained by multiplying the set value of the primary resistance and the exciting current command value, the torque current command value and the set value of the equivalent leakage inductors value are set. The excitation component voltage is obtained from the value obtained by multiplying the primary frequency and the product value obtained by multiplying the setting value of the primary resistance by the torque current, and the setting value of the primary inductors and the excitation current. The torque component voltage is obtained from the magnetic flux command value obtained by multiplying the command value and the multiplication value obtained by multiplying the primary frequency, and by the primary voltage obtained from the excitation component voltage and the torque component voltage. Since the magnetic flux command value obtained by multiplying the set value of the primary inductance and the exciting current command is changed, a large load is applied in a state where the rotation speed of the induction motor is constant and the output voltage is not saturated,
When the torque current command increases, the torque component voltage increases, and the excitation component voltage increases, saturation of the primary voltage and the three-phase output voltage can be reliably detected, and the magnetic flux command value can be determined. By making it small, the saturation of the primary voltage V ₁ and the output voltage of the three phases can be prevented, and the deterioration of the vector control can be prevented.

According to the twenty-sixth and twenty-eighth aspects of the present invention, the product value obtained by multiplying the set value of the primary resistance and the exciting current command value, the set value of the torque current command value and the set value of the equivalent leakage inductors value. The excitation component voltage is obtained from the value obtained by multiplying the primary frequency with the value obtained by multiplying the setting value of the primary resistance by the torque current, and the setting value of the primary inductor and the excitation current. The torque component voltage is obtained from the magnetic flux command value obtained by multiplying the command value and the multiplication value obtained by multiplying the primary frequency, and the setting value of the primary inductors is multiplied by the exciting current command value. According to the magnetic flux command value obtained by changing the constant determined by the induction motor,
It is possible to improve the difference between the actual speed estimation gain and the constant, so that the rotation set speed matches the actual rotation speed, and vector control with high speed accuracy can be performed.

According to the twenty-seventh aspect of the invention, in the twenty-sixth aspect of the invention, since the change of the constant determined in advance by the induction motor is made gentle, the change of the estimated rotation speed is made gentle, and the vibration of the rotation speed is suppressed. You can

[0051]

(Embodiment 1) FIG. 1 shows an embodiment corresponding to the inventions of claims 1 and 2. In this embodiment, the induction motor 4 is PW
The present invention is applied to a device that controls driving by an M (pulse width modulation) type inverter 3. In the following explanation, PWM
The case of application to the inverter 3 of the system will be described, but the invention can also be applied to an apparatus using another frequency converter such as an inverter of another system or a cycloconverter.

In this embodiment, the exciting current command value i_1d ^*, To
Luk current command value i_1q ^*And the primary frequency ω,
The primary voltage of the rotating coordinate system (d-
d-axis and q-axis components of the primary voltage in the q coordinate system)
V_1d ^*, V_1q ^*Is calculated. From this vector operation unit 1
D-axis and q-axis composition of primary voltage as given voltage command
Minute V _1d ^*, V_1q ^*In the coordinate converter 2
Voltage of fixed coordinate system according to phase angle command value θ of bundle vector
Command value Vu^*, Vv^*, Vw^*Convert to. And the seat
Voltage command value Vu given from the standard converter 2^*, Vv^*，
Vw^*Causes the inverter 3 to apply a voltage to the induction motor 4.
The pressure is controlled to control the speed of the induction motor 4. In addition,^*
The symbol indicates that it is a command value, and the following notation
Perform according to the above.

Torque applied to the vector computing unit 1
Current command value i_1q ^*And the primary frequency ω is
The detected phase currents iu, iv, iw of the induction motor 4,
Rotation speed command value ω_r ^*And according to. The rotation speed
Degree command value ω_r ^*Is given from the outside, and the exciting current command value i
_1d ^*Is also given from the outside. First, the torque current command value i
_1q ^*Is calculated as follows. Detected by the current detector 5
The phase currents iu, iv, iw of the induction motor 4 to be
The converter 6 follows the phase angle command value θ of the secondary flux linkage vector.
To the rotating coordinate system, and the exciting current i_1dAnd torque current_1q
And ask. Torque current i thus obtained_1qWhen,
The proportional constant (K) determined by the induction motor 4 is multiplied by the multiplier 7
Estimated value of slip angular frequency multiplied by_sAsk for. This
Estimated value of slip angular frequency of_SWill be described later with the subtractor 8.
Slip angular frequency command value ω_S ^*And subtract
The difference Δω_SAsk for. The difference Δω_SWith adder 9
Speed command value ω_r ^*To estimate the rotational speed ^ ω_r
Ask for. Estimated value of this rotation speed ^ ω_rWith subtractor 10
Rotation speed command value ω_r ^*The actual rotation speed ω
_r(However, estimated value ω_r) And the rotation speed command value ω_r ^*Difference
Δω_rAsk for. This difference Δω_rTorque current finger to zero
I i_1q ^*Is calculated by the speed controller 11. Speed controller 11
Torque current command value i_1q ^*As a method of obtaining
For example, there is PI (proportional / integral) control. The symbol ^ is
Indicates a fixed value, and the following notations are
U

By the way, the estimated value of the slip angular frequency ^ ω _S
The difference Δω _S of the slip angle and the frequency command value ω _S ^* and by adding the rotation speed command value ω _r ^*, request an estimate ^ ω _r of the rotational speed, the rotational speed and the estimated value ^ ω _r of the rotation speed Command value ω _r ^*
Difference Δω _r obtained by subtracting the bet is, the difference between the result in the estimated value of the slip angular frequency ^ ω _S and the slip angular frequency command value ω _S ^* Δω
Matches _S. Therefore, without using the adder 9 and the subtractor 10, the difference Δω _S between the estimated value ^ ω _S of the slip angular frequency and the slip angular frequency command value ω _S ^* is directly input to the speed controller 11, and the difference Δω _The result is the same even if the speed controller 11 obtains the torque current command value i _1q ^* that makes _S zero. However, in the present embodiment, the block diagram is shown in order to clarify that the speed controller 11 operates so that the rotation speed command value ω _r ^* and the actual rotation speed ω _{r become} zero.

Next, the primary frequency ω is obtained as follows. The torque current command value i _1q ^* obtained by the above method is multiplied by the proportional constant (K) predetermined in the induction motor 4 in the multiplier 12 to obtain the slip angular frequency command value ω _S ^* . Slip angular frequency command value ω _S ^* obtained in this case
Is used for subtraction with the estimated value ^ ω _S of the slip angular frequency in the subtractor 8. Then, the slip angular frequency command value ω _S ^* is added to the rotational speed command value ω _r ^* by the adder 13 to obtain the primary frequency ω. The phase angle command value θ of the secondary interlinkage magnetic flux vector used in the coordinate converters 2 and 6 is obtained by integrating the primary frequency ω with the integrator 14.

The principle of the vector control method of this embodiment will be described below. The voltage equation of the induction motor is given by the following equation in an orthogonal coordinate system (dq coordinate system) that rotates at the angular frequency (primary frequency) ω of the secondary flux linkage.

[0057]

[Equation 1]

(1) where r ₁ and r ₂ are primary and secondary resistance values of the induction motor, respectively L ₁ and L ₂ are primary and secondary inductance values including the leakage inductance component M: primary winding Inductance value between the secondary winding and the secondary winding σ: 1-M ² / L ₁ L ₂ leakage coefficient ω _S : slip angular frequency p: d / dt differential operator V _1d , V _1q : respectively D-axis and q-axis components of primary voltage i _1d , i _1q : d-axis and q-axis components of primary current, that is, exciting current and torque current φ _2d , φ _2q : d-axis and q-axis of secondary interlinkage magnetic flux, respectively Component Moreover, the secondary interlinkage magnetic flux is expressed as follows.

[0059] The _{φ 2d = Mi 1d + L 2} i 2d φ 2q = Mi 1q + L 2 i 2q ... (2) vector control, φ _2d = Mi _1d (constant), φ _2q = 0 and becomes as primary voltage or This is to control the primary current. If this condition is satisfied, the slip angular frequency ω _S is given by equation (3).

[0060]

[Equation 2]

However, φ_2d= Mi_1d(Constant), φ_2q= 0
Otherwise, the slip angular frequency ω _SIs like equation (4)
become.

[0062]

[Equation 3]

In other words, the torque current i _1q and the primary frequency ω may be controlled so that the error component of the equation (4) becomes zero. Rotation speed command value ω _r ^* and estimated rotation speed ^ ω _r
Torque current command value i _1q ^*
And a constant K = Mr ₂ / (L determined by the induction motor 4
_The slip angular frequency command value ω _S ^* is obtained by multiplying by ₂ φ _2d ). The primary frequency ω can be obtained by adding the rotational speed command value ω _r ^* to the slip angular frequency command value ω _S ^* .
Here, if the slip angular frequency command value ω _S ^* and the slip angular frequency ω _S are equal, the rotational speed command value ω _r ^* and the rotational speed ω _r of the induction motor match, and speed control without a speed detector is performed. realizable.

Therefore, assuming that the slip angular frequency command value ω _S ^* and the slip angular frequency ω _S are equal and the estimated slip angular frequency value ^ ω _S is given by equation (5), the slip angular frequency command value ω _S ^* Difference between the estimated slip angular frequency ^ ω _S and Δω _S
Represents the error component in equation (4).

[0065]

[Equation 4]

The estimated rotational speed ^ ω _r is the rotational speed command value ω _r
The estimated value ^ ω _S of the slip angular frequency command value ω _s ^* and the slip angular frequency since it is obtained by adding the Δω _s obtained by subtracting the ^*, the rotation speed command value ω _r ^* and the estimated value of the rotation speed ^ Ω _r
Corresponds to the difference Δω _S between the slip angular frequency command value ω _S ^* and the estimated slip angular frequency ^ ω _S. Therefore, the torque current command value i _1q ^* functions to make the difference Δω _S zero.

[0067] In other words, assuming that the actual value of the slip angular frequency command value ω _S ^* and the slip angle frequency as described above are the same, slip angular frequency command value ω _S ^* and the slip angle estimated value of the frequency ^ ω the difference [Delta] [omega _S and _S represents the error component due to the phase difference between the control flux axis and the actual magnetic flux axis and the difference [Delta] [omega _S controls the torque current command value i _1d ^* to be zero,
The slip angular frequency command value ω _S ^* and the estimated slip angular frequency ^ ω _S both match the actual value. That is, the rotation speed ω _r of the induction motor 4 can be matched with the rotation speed command value ω _r ^* .

Here, the vector operation unit 1 uses φ _2d = Mi
Excitation current command value i so that _1d (constant) and φ _2q = 0
The d-axis and q-axis components V _1d ^* and V _1q ^* of the primary voltage are calculated from _1d ^* , the torque current command value i _1q ^* , and the primary frequency ω. Specifically, in the steady state (differential term is zero),
Substituting φ _2d = Mi _1d (constant) and φ _2q = 0 into the equation (1), it is given by the following equation.

[0069]

[Equation 5]

(9) The above equation (9) is shown in a block diagram as shown in FIG. Here, in FIG. 1, L ₁ · i _1d is φ.
According to the vector control method of the present embodiment, the obtained torque current i _1q is multiplied by the constant K determined in advance by the induction motor 4 to obtain the estimated value ^ ω _S of the slip angular frequency, and the estimated value of the slip angular frequency is calculated. ^ omega calculates a difference [Delta] [omega _S between _S and slip angular frequency command value omega _S ^*, obtains the torque current command value i _1d ^* performs further operations to the difference [Delta] [omega _S to zero, the torque current command value i _1d ^* Is multiplied by a constant K determined in advance by the induction motor 4 to obtain the slip angular frequency command value ω _S ^* , and the rotational speed command value ω _r ^* is added to the slip angular frequency command value ω _S ^* to obtain the primary frequency ω. Therefore, the control calculation becomes simple. That is, the torque current command value i given to the vector calculation unit 1
_1d ^* and the primary frequency ω are calculated by using the speed controller 11, the multipliers 7 and 12, the subtractors 8 and 1 without using the current controller.
0, adders 9 and 13 can be achieved, and the control calculation becomes simple.

By the way, the vector operation unit 1 has
Inductance L of the induction motor 4 that has been partially set₁And the
Consider the case where the inductance of the induction motor 4 is different
Consider, inductance L₁Can have the correction function of
desirable. That is, it is set in the vector calculation unit 1.
Inductance motor inductance L₁And the actual induction
If the inductance of the motive is different, the exciting current command value i
_1d ^*And the actual excitation current i_1dThere is an error in
Fluctuates, and as a result, the excitation current and torque current are
Varies from the official price. Therefore, φ_2d= Mi_1d(Constant),
φ_2q= 0 does not hold, and the estimated value of the rotation speed ω_r ^*To
Also causes an error, and the speed accuracy of the induction motor 4 deteriorates.

[0072] Therefore, by correcting the exciting current command value i _1d ^* and the actual induction motor 4 of the exciting current the exciting current instruction value so as to eliminate the error between the i _1d i _1d ^*, the induction motor inductance L ₁ Correct the setting error. Specifically, the vector operation unit 1 to the exciting current command value i _1d ^*, obtains a difference .DELTA.i _1d subtracts the subtractor 15 and the excitation current i _1d obtained by the coordinate converter 2, the difference .DELTA.i _1d The current controller 16 adjusts the d-axis component V _1d ^* of the primary voltage so as to eliminate it.

Here, the induction motor 4 has the same rating.
For example, the magnetic flux is almost equal regardless of the type of electric motor. Well
Also, the magnetic flux is obtained by the product of the inductance and the exciting current.
And the exciting current command value i_1d ^*And exciting current i_1dBased on the error between
Then, the d-axis component V of the primary voltage _1d ^*Adjust the excitation power
Flow i_1dIs the exciting current command value i_1d ^*Correct to match
If so, the inductance setting error can be corrected.
It In this way, the guidance in the vector operation unit 1
Motor inductance L₁No effect of setting error
Comb can prevent deterioration of speed accuracy.

(Embodiment 2) This embodiment corresponds to the inventions of claims 3 and 4, and the configuration is shown in FIG. Since this embodiment is basically the same as the first embodiment, the same components as those of the first embodiment are denoted by the same reference numerals and symbols, and the following description will be made only on different points. For the operation and role of the configuration common to the first embodiment, refer to the description of the first embodiment.

In this embodiment, the torque current and the slip angular frequency are
Is proportional to the slip angular frequency,
In the same manner as in Example 1, the induction motor
Degree control. Slip angular frequency ω_SIs Tor
Current i_1qCalculated by multiplying by the proportional constant (K) of the induction motor
To be Therefore, in this embodiment, the torque current command value i_1q ^*
And torque current i_1qDifference Δi_1q(The subtractor 17
Luk current command value i_1q ^*And torque current i_1qSubtract with
I), this difference Δi_1qIs multiplied by a proportional constant (K) (multiplier
18 difference Δi _1qMultiplied by K), the slip angular frequency command value
ω_S ^*Difference between the actual slip angular frequency and Δω_S(Example 1
Slip angular frequency command value ω_S ^*And slip angular frequency
Estimated value of ^ ω_SDifference Δω_SEquivalent to)
It is the one. Even in this case, in the case of the first embodiment
The speed can be controlled in the same manner as.

(Embodiment 3) This embodiment corresponds to the invention of claims 13 to 15, and FIG. 3 shows the configuration of the embodiment. First, the problems to be achieved by this embodiment will be described. In a general-purpose inverter, since it is not possible to request the user to set the electric motor constant according to the induction motor to be driven, an average electric motor constant is set in advance. However, the vector calculation unit 1 calculates the voltage command value based on the motor constant so that the desired exciting current and torque current are obtained. Therefore, if the electric motor constant preset in the vector calculation unit 1 and the electric motor constant to be driven are different, the voltage command fluctuates, and as a result, the exciting current and the torque current fluctuate from the command values. Therefore, φ _2d = Mi _1d (constant) and φ _2q = 0 are not established, and the estimated value of the rotation speed ω
_An error also occurs in _r ^*, and the speed accuracy of the induction motor deteriorates.

The fluctuation of the voltage command value due to the setting error of the electric motor constant is obtained from the equation (9) as follows. ΔV _1d ^* = Δr ₁ i _1d ^* −σΔL ₁ ωi _1q ^* ΔV _1q ^* = ΔL ₁ ωi _1d ^* −Δr ₁ i _1q ^* (10) where Δr ₁ = r ₁ −r ₁ ^* ΔL ₁ = L ₁ -L ₁ ^* (10) as is apparent from the equation, setting error [Delta] r ₁ is in its variation, the influence of [Delta] L ₁ are mixed. Further, when the primary frequency ω is small, the influence of ΔL ₁ is small, and Δr 1
_The effect of ₁ becomes large. Conversely, when the primary frequency ω is large, the influence of ΔL ₁ becomes large. further,
It can be seen that in the stopped state (ω = 0), the inductance L ₁ has no effect. The set value is also
Display with ^* .

The primary resistance r is shown in FIG.₁Set value and motor constant
Excitation current i due to the error of_1dShows the change of. Electric motor from the figure
Constant r₁Is the set value r₁ ^*If larger, the exciting current i_1d
Is its command value i_1d ^*It gets smaller. Inductor
Setting value L₁ ^*And motor constant L₁Excitation due to error
Magnetic current i_1dShows the change of. This inductance is also
Motivation constant L₁Is the set value L₁ ^*If larger, the exciting current
i_1dIs its command value i_1d ^*It gets smaller.

Therefore, in this embodiment, the vector calculation unit 1
Primary resistance setting value r₁ ^*And inductance setting
Value L₁ ^*Is the primary resistance r which is the actual motor constant₁,once
Inductance L₁It is designed to be corrected according to
is there. The configuration of this embodiment is basically the same as that of the first embodiment.
Is. However, in this embodiment, as will be described later,
Proportional constant K, set value r of primary resistance₁ ^*Correction of
And multiply by the proportional constant K corrected as the multipliers 7 and 12.
And the primary resistance of the vector calculation unit 1
Primary resistance r corrected as a multiplier for multiplying₁ ^*Squared
It uses the one to calculate.

In the present embodiment, the following configuration is added as a configuration for correcting the primary resistance set value r ₁ ^* and the inductance set value L ₁ of the vector calculation unit 1. In addition,
Also in this embodiment, the inductance is corrected by correcting the exciting current command value i _1d ^* . Then, in order to correct the set value r ₁ ^* of the primary resistance and the exciting current command value i _1d ^* , the initial set value r ₁ ^{* of the} primary resistance and the initial command value i _1d ^{* of the} exciting current command value are externally applied. I'm giving it.

Set value r of primary resistance₁ ^*For the correction of
Excitation current command value i obtained by the subtracter 15_1d ^*And excitation electric
Flow i_1dDifference Δi_1dCorrection value of the primary resistance so that
Δr ₁ ^*And an identifier 20 for determining
Corrected value of primary resistance Δr₁ ^*And the initial setting value r of the primary resistance
₁ ^*′ And an adder 23 for performing addition with ‘ Well
Excitation current command value i_1d ^*Subtractor 15
Exciting current command value i obtained by_1d ^*And exciting current i_1dWith
Difference Δi_1dCorrection value Δi of the exciting current command value so that
_1d ^*The identifier 24 that determines the
Correction value Δi of magnetic current command value_1d ^*Initializing the excitation current command value
Command value i_1d ^*'And a subtractor 26 for subtracting from
It

The set value r of the primary resistance is₁ ^*Correction of
Excitation current command value i_1d ^*To control the correction period of
A switch 21 inserted between the regulator 20 and the adder 23
And a switch inserted between the identifier 24 and the subtractor 26.
25 and rotation speed command value ω _r ^*Based on each
Switch control circuit 22 for controlling the opening and closing of switches 21 and 25
And are provided.

Further, in this embodiment, the exciting current command value i_1d
^*Induced current that must be corrected as the
Secondary resistance r of motive 4₂Of the secondary resistance r
₂In order to correct the proportional constant K according to
Initial setting value r of secondary resistance of₂ ^*’Is given externally and identified
Correction value Δi of the exciting current command value obtained by the device 24_1d ^*From two
Next resistance correction value Δr₂ ^*And the secondary resistance
Initial setting value r₂ ^*’The correction value Δi of the excitation current command value
_1d ^*Is added to set the secondary resistance r₂ ^*Adder to find
29 and the set value r of the secondary resistance obtained by the adder 29₂ ^*To
And a multiplier 30 for multiplying 1 / φ to obtain a proportional constant K.
There is a mark.

The operation of the configuration added above will be described below.
It Rotation speed command value ω_r ^*Is zero and only exciting current is applied
Period, that is, the induction motor is stopped (ω = 0)
Period T shown in FIG.₁, The inductance L₁
Does not appear at all. Therefore, this period T₁At
When the switch control circuit 22 closes the switch 21,
Both of them open the switch 25 to set the primary resistance setting value r.₁ ^*
Is corrected. The set value r of this primary resistance₁ ^*The correction of
Excitation current command obtained by the subtracter 15 by the identifier 20
Value i_1d ^*And exciting current i_1dDifference Δi_1dIs the primary resistance
Anti-correction value Δr₁ ^*And the correction value Δr₁ ^*Add
The initial setting value r of the primary resistance ₁ ^*’, The primary
Resistance set value r₁ ^*By asking for. Identification above
The device 20 should be, for example, a proportional / integrator
You can

Next, the rotation speed command value ω_r ^*To change
Period T shown in FIG.₂The fluctuation of the exciting current is
Since it can be said that it depends only on the setting error of the closet, this period T
₂Correction by the setting error of the inductance
U However, as described above, the magnetic flux φ (= L₁・ I
_1d) Depends on the type of motor, if the motor rating is the same.
Inductance L₁Can be corrected
Instead of and, the exciting current i _1d ^*To correct
It

This period T₂Then close the switch 25
At the same time, the switch 21 is opened, and the exciting current command value i_1d ^*
Is corrected. This exciting current command value i_1d ^*Is the same
The exciting current command value i obtained by the subtractor 15 by the constant device 24.
_1d ^*And exciting current i_1dDifference Δi_1dExciting current finger with zero
Correction value Δi_1d ^*And the correction value Δi_1d ^*Reduced
Initial command value i of exciting current in calculator 26_1d ^*’
Excitation current command value i_1d ^*Ask for.

By doing so, the set value r ₁ ^{* of the} primary resistance and the set value L _{1 of the} inductance of the vector calculation unit 1 are set.
^{Even if *} is different from the primary resistance r ₁ and the inductance L ₁ of the driven induction motor, the set value r _{1 of the} primary resistance is also set.
^{* And} the set value L ₁ ^* of the inductance can be corrected so as to match the primary resistance r ₁ and the inductance L ₁ of the induction motor, and deterioration of speed accuracy can be prevented.

By the way, the temperature change of the induction motor 4 is a factor that causes an error between the set value r ₁ ^* of the primary resistance and the primary resistance r ₁ of the induction motor 4. Therefore, in this embodiment, the primary resistance r is changed in accordance with the temperature change of the induction motor 4.
_{Even if 1} changes, the set value r ₁ ^{* of the} primary resistance is accordingly changed ^.
Is designed to be corrected. Here, it can be said that the fluctuation of the exciting current in the period T ₃ of FIG. 6 after the correction is only the fluctuation of the primary resistance r _{1 due to} the temperature. Therefore, in this period T ₃ , as in the period T ₁ , the switch control circuit 22
However, the switch 21 is closed and the switch 25 is opened to correct the primary resistance r ₁ . This makes it possible to prevent the speed accuracy from deteriorating even when the primary resistance r ₁ changes due to the temperature of the induction motor 4.

The length (period) of each of the periods T _{1 to} T ₃ may be set in advance according to the rating of the induction motor 4, the driving conditions, etc., or may be changed during operation. By the way, there is a correlation between the inductance of the induction motor and the secondary resistance r ₂ . Therefore, when the set value of the inductance is corrected by correcting the exciting current command value i _1d ^* as described above, the secondary resistance r ₂ also changes accordingly. Therefore,
In this embodiment, the set value r ₂ ^* of the secondary resistance is also corrected, and the proportional constant K of the induction motor 4 is also corrected according to the correction of the set value r ₂ ^* of the secondary resistance.

In this embodiment, the identifier 28 determines the correction value Δr ₂ ^* of the secondary resistance from the correction amount Δi _1d ^* of the excitation current command value due to the setting error of the inductance. The calculation may use the following equation. Δr ₂ ^* = αΔi _1d ^* (11) α: Correlation coefficient Then, the correction value Δr of the secondary resistance obtained by the identifier 28.
₂ ^* is added to the initial setting value r ₂ ^{* of the} secondary resistance in the adder 29 to obtain the setting value r ₂ ^* of the secondary resistance.
Here, since the proportional constant K for converting the torque current i _1q into the slip angular frequency ω _S can be approximated to K = r ₂ / φ, the multiplier 30 multiplies 1 / φ to obtain the proportional constant K. By giving the proportional constant K to the multipliers 7 and 12, the slip angular frequency command value ω _S ^* and the estimated slip angular frequency value ^ ω _S are obtained by the proportional constant K corrected according to the setting error of the inductance. By doing so, it is possible to further reduce deterioration in speed accuracy.

The configuration for obtaining the primary frequency ω in this embodiment is basically obtained by the same method as in the first embodiment, but the proportional constant K of the multipliers 7 and 12 is obtained by the multiplier 30 as described above. Is different. In the first to third embodiments, the primary frequency ω is calculated by adding the rotational speed estimation value ^ ω _r and the slip angular frequency command value ω _s ^* .
Each value when the rotation speed command value ω _r ^* changes rapidly is as shown in FIG. 7. Note that ω _r represents the actual rotation speed.
As can be seen from FIG. 7, when the rotational speed command value ω _r ^* changes abruptly, the primary frequency ω also changes abruptly, causing an excessive current to flow in the induction motor 4 and causing a circuit breakdown or the operation of the protection circuit. May stop rotating.

In view of this point, Examples 4 and 5 described below were made. (Embodiment 4) This embodiment corresponds to the inventions of claims 5 and 6, and FIG. 8 shows the configuration thereof. In the present embodiment, as in the third embodiment, the current controller 16 is provided in the vector operation unit 1 to adjust the d-axis component V _1d ^* of the primary voltage, and L ₁ · i _1d ^* in the equation (9) is set to φ. I am trying. Then, instead of adding the rotation speed command value ω _r ^* and the slip angular frequency command value ω _s ^* by the adder 13, the rotation speed estimated value ^ ω _r and the slip angular frequency command value ω _s ^* are added by the adder 13. The feature is that the primary frequency ω is obtained by adding.

Thus, in this embodiment, the rotation speed command value ω
Fig. 9 shows the simulation results for each value with a rapid increase in _r ^* . In the transient state at the time of startup, the estimated rotational speed ^ ω _r does not match the actual rotational speed ω _r because the slip angular frequency command value ω _s ^* differs from the estimated slip angular frequency ^ ω _s. It can be seen that the rotation speed command value ω _r ^* gradually increases and the maximum value of the primary current decreases.

[0094] This means that the rate of change of the rotational speed estimated value ^ ω _r is small compared to the rotation speed command value ω _r ^* the rate of change, the added value of its order slip angular frequency command value ω _s ^* and the rotational speed estimated value ^ ω _r The rate of change of the primary frequency ω is also small, and eddy current due to excessive slip angular frequency can be suppressed. (Embodiment 5) This embodiment corresponds to the inventions of claims 7 and 8, and FIG. 10 shows the configuration thereof. This embodiment is basically the same as the fourth embodiment, but in this embodiment, the deviation Δω _s between the slip angular frequency command value ω _s ^* and the slip angular frequency estimation value ω _s is obtained by the subtractor 8. After this deviation deviation Δω _s
And the proportional constant K which is obtained in advance are multiplied by the multiplier 31 to obtain the primary frequency correction value, and the primary frequency correction value and the rotation speed estimated value ^ ω _r and the slip angular frequency command value ω _s ^* are added. The feature is that the primary frequency ω is obtained by the addition by the device 13 ′.

Thus, in this embodiment, the rotation speed command value ω
Fig. 11 shows the simulation results for each value obtained by rapidly increasing _r ^* . Here, in the transient state at the time of start-up, the torque current i _1q rapidly increases, so the estimated value ω _s of the slip angular frequency becomes larger than the slip angular frequency command value ω _s ^* , and the deviation Δω _s becomes a negative value. Become.
By multiplying this negative deviation Δω _s by an appropriate proportional constant (gain) K and adding it to the primary frequency command value, the rate of change of the primary frequency ω becomes small and the maximum value of the primary current becomes small.

That is, the deviation Δω _s between the slip angular frequency command value ω _s ^{* of the} primary current and the estimated slip angular frequency ^ ω _s increases due to the abrupt change of the primary frequency ω, and the primary frequency ω ω increases in accordance with this deviation Δω _s. Since it functions to suppress the change in ED, eddy current due to excessive slip angular frequency can be suppressed. Further, the waveform of the primary current can be finely adjusted by adjusting the degree of primary frequency correction due to the deviation Δω _s .

(Embodiment 6) This embodiment is made in consideration of the following points. That is, in the transient state, a differential term appears, and the slip angular frequency ω _s becomes as shown in equation (12).

[0098]

[Equation 6]

(12) This is obtained by substituting (9) into equation (13) obtained by modifying the state equation of equation (1) and solving for the slip angular frequency ω _s .

[0100]

[Equation 7]

(13) l ₁ , l ₂ ; primary and secondary leakage inductances r ₂ '= r ₂ (M / L ₂ ) ² l ₂ ' = l ₂ M / L ₂ Rotation speed command value ω _r FIG. 12 shows the relationship between the set value and the actual value of the slip angular frequency ω _s when the slip angular frequency ω _s is changed in a circular shape. From the expression (12), the magnitude relationship between the actual value and the set value of the slip angular frequency ωs changes depending on the polarity of the differential value of the torque current i _1q .

In response to such a point, FIG.
As shown in FIG. 3, the speed controller 11 used in the first to fifth embodiments is not used, but the delay circuit 32 is used. That delay circuit 32 is for outputting the delayed torque current i _1q 'is delayed torque current i _1q, and the subtractor 32a, is composed of a controller 32b, a subtracter 32a from the torque current i _1q The delay torque current i _1q 'is subtracted, the subtracted value is output to the controller 32b, and the controller 3
2b outputs the delay torque current i _1q so that the difference becomes zero, and is composed of, for example, a proportional-integrator.

The controller 32b can arbitrarily design the delay characteristic as shown in FIG. 14 by adjusting its proportional and integral gains. Fig. 1 shows the relationship between the torque current and the primary frequency ω when the rotational speed command value ω _r is changed stepwise.
5 shows. As can be seen from this figure, the rate of increase of the primary frequency ω is suppressed and slippage is prevented. B represents the undelayed primary frequency ω, and B represents the delayed primary frequency ω.

Here, the vector operation unit 1 uses φ _2d = Mi _1d
The d-axis and q-axis components V _1d ^* , V _1q ^* of the primary voltage are calculated from the excitation current command value i _1d ^* , the detected torque current i _1q and the primary frequency ω so that φ _2d = 0 (constant). Specifically, it is given by the above equation (9). Further, in this embodiment, in order to match the exciting current i _1d with the exciting current command value i _1d ^* , the current controller 16 that adjusts the d-axis component V _1d ^* of the primary voltage based on the difference in the exciting current i _1d ^* is used. Is added in the same manner as in the above example, and L ₁ · i _1d ^* in the above equation (9)
I am trying.

(Embodiment 7) This embodiment corresponds to the inventions of claims 16 and 17, and FIG. 16 shows the configuration of this embodiment. In the configuration of the present embodiment, the configuration for obtaining the primary frequency ω _s has the same configuration as that of the first embodiment of FIG.
The configuration of the vector operation unit 1 is different. That is, the vector operation unit 1 is divided into vector operation units 1a and 1b, and one vector operation unit 1a multiplies the exciting current command value i _1d ^{* by} the set value of the primary resistance r ₁ to obtain the leakage coefficient σ,
The excitation component voltage V _1d ^* is obtained by subtracting the product of the primary inductance L ₁ , the primary frequency ω and the torque current command value i _1q ^* . Further, the other vector calculation unit 1b first multiplies the primary inductance L ₁ and the exciting current command value i _1d ^* to obtain the exciting command value φ, and then the detected torque current i _1q and the set value of the primary resistance r ₁ . And the magnetic flux command value φ and the primary frequency ω multiplied by the multiplier 40 are added by the adder 41 to obtain the torque component voltage V _1q ^* . In the coordinate converter 2, the inverter 3
In order to obtain the output voltages of the three phases, the equation (14) is calculated to obtain the primary voltage V ₁ . This primary voltage V
₁ and the primary frequency ω are calculated to obtain the output voltages of the three phases.

[0106]

[Equation 8]

This makes it possible to improve the speed response characteristic when a load torque is applied. (Embodiment 8) Instead of the torque current command value i _1q ^* of Embodiment 7, the present embodiment uses the same delay circuit as the delay circuit 32 used in FIG. 13 as shown in FIG. 17 to delay the torque current. The value i _1q 'is used. The operation and configuration of the delay circuit 32 are the same as those of the delay circuit 32 of FIG. 13, and the multiplier 12 multiplies this delay value i _1q ′ and the proportional constant K to obtain the slip angular frequency command value ω _s ^* . The vector calculation unit 1a calculates the leakage current σ, the primary inductance L ₁ , the primary frequency ω, and the torque current delay value i from the product of the excitation current command value i _1d ^* and the set value of the primary resistance r _1.
The excitation voltage _V1d ^* is obtained by subtracting the product of _1q '.

The other configurations are the same as those of the first and seventh embodiments.
Since it is the same as
Omit it.  (Embodiment 9) This embodiment is the invention of claims 18 to 20.
Correspondingly, FIG. 18 shows the configuration of the present embodiment. Real
The configuration of the embodiment is similar to that of the seventh embodiment and includes two vector operation units 1
Although a and 1b are provided, the configuration of the vector operation unit 1b is
This is different from the seventh embodiment.

That is, the vector calculation unit 1b calculates the torque component voltage V _1q ^* from the judgment unit 42 that judges whether the primary frequency ω is higher than a certain frequency and the signal sent from the judgment unit 42. Switch S determines whether the torque current to be used is the torque current command value i _1q ^* or the detected torque current i _1q .
Switching device 43 that switches between Wa and SWb, and torque current switched by switching device 43 (either torque current command value i _1q ^* or detected torque current i _1q )
And a multiplier 44 that multiplies the set value of the primary resistance r ₁ and an adder 41 that adds the output of the multiplier 44 and the output of the multiplier 40 that multiplies the magnetic flux command value φ and the primary frequency ω.

Here, a method of calculating the excitation voltage V _1d ^* and the torque voltage V _1q ^* will be described. First, the excitation voltage V _1d ^*
Is calculated by multiplying the exciting current command value i _1d ^* and the setting value of the primary resistance r ₁ by the multiplier 40, and then the leakage coefficient σ, the primary inductance L ₁ , the primary frequency ω, and the torque current command value i _1q ^* This is done by subtracting the product of. Further, the calculation of the torque component voltage V _1q ^* is performed by the vector calculation unit 1b, and the judging device 42 judges whether the primary frequency ω is higher than a certain frequency. In the switching device 43, when it is small, the switch SWa is switched. If it is larger, the switch SWb is closed. As a result, the torque current used to calculate the torque component voltage V _1q ^* is determined to be the torque current command value i _1q ^* or the detected torque current i _1q . This determined torque current is sent to the multiplier 44, and the primary resistance r
The value obtained by multiplying the set value of ₁ by the output of the magnetic flux command value φ obtained by the multiplier 40 and the primary frequency ω is added by the adder 41.
The torque component voltage V _1q ^* is obtained by adding in. As a result, it becomes possible to suppress the oscillation of the torque current when the rotation speed of the induction motor 4 increases,
Stable speed response with good control can be performed regardless of the set speed.

(Embodiment 10) Instead of the torque current command value i _1q ^* of Embodiment 9, this embodiment uses a delay circuit the same as the delay circuit 32 used in FIG. 13, as shown in FIG. The current delay value i _1q 'is used. The operation and configuration of the delay circuit 32 are the same as those of the delay circuit 32 of FIG. 13, and the multiplier 12 multiplies this delay value i _1q ′ and the proportional constant K to obtain the slip angular frequency command value ω _s ^* . The vector calculation unit 1a multiplies the exciting current command value i _1d ^* and the set value of the primary resistance r _{1 by} the leakage coefficient σ, the primary inductance L ₁ , the primary frequency ω and the torque current delay value i _1q ′. The excitation voltage V _1d ^* is obtained by subtracting the obtained voltage.

In the vector calculation unit 1b, the primary frequency ω
Is larger than a certain frequency by the judgment device 42
However, in the switching device 43, when it is small, the switch SW
When a is large, the switch SWb is closed. this thing
By the torque component voltage V_1q ^*Torque used to calculate
Current is the delay value i of torque current_1q'Or detected torque current
i_1qDecide

The other structure is the same as that of the ninth embodiment.
Therefore, the description of the configuration and operation is omitted. (Embodiment 11) This embodiment is an invention corresponding to claim 9.
Which corresponds to the inventions of claims 21 to 23.
The basic configuration is the same as in the seventh and eighth embodiments, but FIG.
As shown in 0, the primary voltage V₁But
A judgment device 45 that judges whether the voltage is higher than a certain voltage
The switching device 43 is provided from the judging device 45.
Torque component voltage V from signal_1q ^*Torque used to calculate
Flow to torque current command value i _1q ^*Detected torque current i_1q
So that it can be switched by switches SWa and SWb
It is characterized in that it has become.

The torque current (either the torque current command value i _1q ^* or the detected torque current i _1q ) switched by the switching device 43 is the set value of the primary resistance r ₁ and the multiplier 44.
The output of the multiplier 44 is added by the adder 41 to the output of the multiplier 40 that multiplies the magnetic flux command value φ by the primary frequency ω. Here, the excitation voltage V _1d ^* and the torque voltage V _1q
The calculation method of ^* is explained. First, the excitation voltage V _1d ^* is calculated by multiplying the excitation current command value i _1d ^* and the setting value of the primary resistance r ₁ by 40, and then the leakage coefficient σ, the primary inductance L ₁ , the primary frequency ω and the torque current Command value i _1q ^*
It is done by subtracting what is multiplied by.
The calculation of the torque component voltage V _1q ^* is performed by the vector calculation unit 1b.
The determining device 45 determines whether the primary voltage V ₁ is higher than a certain voltage. In the switching device 43, the switch SWa is selected when the voltage is small and the switch SWb is selected when the voltage is large.
Close. As a result, the torque current used to calculate the torque component voltage V _1q ^* is determined to be the torque current command value i _1q ^* or the detected torque current i _1q . The determined torque current is sent to the multiplier 44, multiplied by the set value of the primary resistance r ₁ , and the output is multiplied by the magnetic flux command value φ obtained by the multiplier 40 and the primary frequency ω by the adder 41. By adding, the torque component voltage V _1q ^* is obtained. By this,
It becomes possible to suppress the oscillation of the torque current when the rotation speed of the induction motor 4 becomes high, and it is possible to perform stable control with good speed response regardless of the set speed.

(Embodiment 12) Instead of the torque current command value i _1q ^* of the above-mentioned Embodiment 9, this embodiment uses the same delay circuit as the delay circuit 32 used in FIG. 13 as shown in FIG. The current delay value i _1q 'is used. The operation and configuration of the delay circuit 32 are the same as those of the delay circuit 32 of FIG. 13, and the multiplier 12 multiplies this delay value i _1q ′ and the proportional constant K to obtain the slip angular frequency command value ω _s ^* . The vector calculation unit 1a multiplies the exciting current command value i _1d ^* and the set value of the primary resistance r _{1 by} the leakage coefficient σ, the primary inductance L ₁ , the primary frequency ω and the torque current delay value i _1q ′. The excitation voltage V _1d ^* is obtained by subtracting the obtained voltage.

In the vector calculation unit 1b, the primary voltage V ₁
Judgment device 45 judges whether the voltage is higher than a certain voltage,
In the switching device 43, when it is small, the switch SWa
When it is larger, the switch SWb is closed. As a result, the torque current used to calculate the torque component voltage V _1q ^* is the torque current command value i _1q ^* or the detected torque current i _1q.
Decide

Since the other structure is the same as that of the eleventh embodiment, the description of the structure and operation will be omitted. (Embodiment 13) When the rotational speed of the induction motor 4 increases or a load is applied, the torque component voltage V _1q ^* increases, and the primary voltage obtained from the equation (4) shown in the description of Embodiment 7 is obtained. There is a problem that V ₁ and the output voltage of the inverter 3 are saturated.

This embodiment is made in view of this point, and corresponds to the inventions of claim 24, claim 25, claim 26, and claim 28. FIG. 22 shows the present embodiment. The present embodiment basically corresponds to the third embodiment in the configuration for obtaining the primary frequency ω and the configuration of the vector calculation unit 1, but has the following features. .

That is, the primary voltage V ₁ obtained by the coordinate converter 2
Is detected by the detector 50, and when the primary voltage V ₁ is saturated, the multiplier 4 of the vector operation unit 1 is detected.
0 to reduce the magnetic flux command value φ, and the torque component voltage V _1q
^{Reduce *} . In other words, the magnetic flux command value φ is reduced so that the primary voltage V ₁ does not exceed the DC voltage of the inverter 3, that is, the DC power supply voltage E in the basic circuit configuration of the inverter 3 shown in FIG. 23, and the torque component voltage V _1q ^* is set. Make it smaller. As a result, the primary voltage V ₁ and the inverter 3
It prevents the output voltage of three phases from being saturated. Therefore, not only the rotation speed of the induction motor 4 but also the torque component voltage V due to the load
It is possible to reliably detect the saturation of the primary voltage V ₁ and the output voltage of the three phases due to the fluctuation of _1q ^{* and} the fluctuation of the excitation component voltage V _1d ^* , and as a result, it is possible to prevent the saturation.

The primary voltage V₁And exhaustion of the output voltage of three phases
Even if the sum is prevented, in the speed accuracy, the speed estimation gain
It becomes worse due to the deviation of (Km). Improve this property
In order to do so, the primary voltage V₁Is saturated
When detected and saturated, the power is applied when the magnetic flux command value φ is changed.
Send the changed magnetic flux command value φ to the calculators 7 and 12
Constant determined by machine 4 Km = Mr₂/ (L₂φ_2d) Is changed
You can do it. The method is φ_2d= Mi_1d ^*Km = r
₂/ (L₂i_1d ^*). In addition, the primary inductor L₁
And the secondary inductance L₂Is almost equal to Km = r
₂/ (L₁i_1d ^*). Where L₁i_1d ^*Is the primary
Inductance L₁And exciting current command value i_1d ^*Multiplied by
That is, the magnetic flux command value φ itself. Therefore K
m = r₂/ Φ, so the magnetic flux command value φ has changed
Sometimes Km = r₂Induction motor 4 based on the formula / φ
Changing the constant Km (speed estimation gain) determined by
become. This improves the deviation of the speed estimation gain from the actual value.
Good and finally find the primary frequency ω in an optimal form
Therefore, the set speed and the actual rotation speed will not match.
Therefore, vector control with high speed accuracy can be performed.

(Embodiment 14) Instead of the torque current command value i _1q ^* of the embodiment 13, the present embodiment uses the same delay circuit as the delay circuit 32 used in FIG. 13 as shown in FIG. The current delay value i _1q 'is used. The operation and the configuration of the delay circuit 32 are the same as those of the delay circuit 32 of FIG. 13, and the multiplier 12 multiplies this delay value i _1q ′ and the proportional constant Km to obtain the slip angular frequency command value ω _s ^*.
Ask for. In the vector calculation unit 1a, the exciting current command value i _1d
^The excitation component voltage is obtained by subtracting the product of the leakage coefficient σ, the primary inductance L ₁ , the primary frequency ω and the delay value i _1q 'of the torque current from the product of ^* and the set value of the primary resistance r _{1. Find} V _1d ^* .

Since the other structure is the same as that of the thirteenth embodiment, the description of the structure and operation will be omitted. (Embodiment 15) Like Embodiment 10, this embodiment corresponds to the saturation of the primary voltage V ₁ and the output voltage of the inverter 3 and is an embodiment according to the invention of claim 27. Figure 2
The configuration of this embodiment shown in FIG. 5 is basically the same as that of the tenth embodiment, and the detector 50 detects whether or not the primary voltage V ₁ is saturated, and sends it to the multiplier 40 to send the magnetic flux command value. Although φ is changed, the changed magnetic flux command value φ is sent to the integrator 51, and the integrator 51 changes the magnetic flux command value φ to the gently changing magnetic flux command value φ ′. This magnetic flux command value φ ′ is sent to the multipliers 7 and 12, and the constant Km = r ₂ / φ ′ determined by the induction motor 4 is changed as in the tenth embodiment. Therefore, in this embodiment, the constant K determined by the induction motor 4 is used.
Since m can be gently changed, it is possible to suppress the vibration of the rotation speed and improve the speed accuracy characteristic.

(Embodiment 16) Torque of the above-mentioned Embodiment 13
Flow command value i_1q ^*Instead of this, this embodiment is shown in FIG.
Using the same delay circuit as the delay circuit 32 used in FIG.
Torque current delay value i_1q’Used
Is. The operation and configuration of the delay circuit 32 is the delay of FIG.
It is the same as the circuit 32, and the multiplier 12 uses this delay value i_1q’
It is adapted to be sent by the multiplier 12. Vector operation
In the section 1a, the exciting current command value i_1d ^*And the primary resistance r₁settings of
From the value multiplied by, the leakage coefficient σ, the primary inductor
L ₁, Primary frequency ω and delay value of torque current i_1q’
By subtracting the product of
_1d ^*Ask for.

Since the other structure is the same as that of the fifteenth embodiment, the description of the structure and operation will be omitted.

[0125]

According to the invention of claims 1 and 2, the slip angular frequency is estimated by multiplying the torque current by a constant determined in advance by the induction motor, and the estimated value of the slip angular frequency is calculated from the slip angular frequency command value. Is subtracted and the subtracted value is added to the given speed command value to obtain the estimated value of the rotational speed of the induction motor, and the torque current command value is obtained based on the difference between the estimated speed value and the speed command value. , The torque current command value is multiplied by a constant obtained from the constant of the induction motor to obtain the slip angular frequency command value, and the slip angular frequency command value and the speed command value are added to obtain the primary frequency. Therefore, it is possible to control the rotation speed of the induction motor at high speed and with high accuracy without using a speed detector or voltage detector. There is an effect that can be configured to Izu. Further, the slip angular frequency is estimated by multiplying the torque current detected from the primary current by a constant determined in advance by the induction motor, the slip angular frequency command is subtracted from the slip angular frequency command, and the subtracted value is given. Since the estimated value of the rotational speed of the induction motor is obtained by subtracting from the speed command value, the estimated speed value can be obtained only by the multiplication and subtraction processing, and the control calculation can be simplified.

According to the inventions of claims 3 and 4, the slip angle frequency is estimated by multiplying the torque current in the invention of claim 1 by a constant determined in advance by the induction motor, and the estimated value of the slip angular frequency and the slip angle are calculated. Instead of the calculation for calculating the difference from the frequency command, the torque current is subtracted from the torque current command, and the difference is multiplied by a constant determined in advance by the induction motor. In other words, since the torque current and the slip angular frequency are in a proportional relationship, even if the torque current is used instead of the slip angular frequency, the speed control of the induction motor can be performed in the same manner as the invention of claim 1.

According to the fifth and sixth aspects of the present invention, the slip angular frequency is estimated by multiplying the torque current by a constant determined in advance by the induction motor, and the slip angular frequency estimated value is subtracted from the slip angular frequency command value. Then, the subtraction value is added to the given speed command value to obtain an estimated value of the rotational speed of the induction motor, and a torque current command value is obtained based on the difference between the speed estimated value and the speed instruction value. The torque current command value is multiplied by a constant obtained from the constant of the induction motor to obtain the slip angular frequency command value, and the slip angular frequency command value and the speed estimated value are added to obtain the primary frequency. Since the rate of change of the rotational speed estimated value is smaller than the rate of change of the rotational speed command value, the rate of change of the primary frequency, which is the sum of the slip angular frequency command value and the speed estimated value, is also small and the slip angular frequency There is an effect of suppressing an overcurrent due to an excessive.

According to the seventh and eighth aspects of the invention, the slip angular frequency is estimated by multiplying the torque current by a constant determined in advance by the induction motor, and the slip angular frequency estimated value is subtracted from the slip angular frequency command value. This subtracted value is added to the given speed command value to obtain the estimated value of the rotation speed of the induction motor, and the torque current command value is obtained based on the difference between the estimated speed value and the speed command value. The slip angle frequency command value is obtained by multiplying the command value by a constant obtained from the constant of the induction motor, and the slip angular frequency command is added to the added value obtained by adding the slip angle frequency command value and the speed command value. Since the primary frequency is obtained by adding the deviation of the slip angular frequency estimated value, the deviation of the command value and the detected value or the delay value of the slip angular frequency of the primary current increases due to the abrupt change of the primary frequency, It will function to suppress the change of the primary frequency according to the deviation of, and as a result, the overcurrent due to the excessive slip angle frequency can be suppressed, and the primary current waveform can be changed by adjusting the degree of the primary frequency correction due to the deviation. There is an effect that it is possible to make fine adjustments.

According to the ninth and eleventh aspects of the invention, the value obtained by delaying the torque current is multiplied by a constant determined in advance by the induction motor, and the product value and the speed command value given are added to determine the primary frequency. Therefore, it is possible to obtain a vector control method and device that can be configured without using a current controller, and can easily perform control calculation. Also, it is possible to suppress an increase rate of the primary frequency and prevent excessive slippage. There is an effect that can be.

According to the invention of claim 10, in the invention of claim 9, since the delay value of the torque current is changed based on the difference between the torque current value and the delay value of the torque current, the delay characteristic of the torque current is designed in detail. Therefore, it is possible to obtain a vector control method and apparatus having optimum speed control characteristics. According to the twelfth aspect of the present invention, the exciting current command value is corrected so as to eliminate the difference between the exciting current detected from the primary current of the induction motor and the exciting current command value. It is possible to eliminate the influence of the setting error of the inductance of the induction motor and prevent the deterioration of speed accuracy, and if the ratings of the induction motor are equal, the magnetic flux is almost the same regardless of the type of the motor, and the magnetic flux is the same as the inductance. Since it is obtained by the product of the exciting current, there is an effect that the setting error of the inductance can be corrected by correcting the exciting current based on the error between the exciting current command value and the exciting current value.

According to a thirteenth aspect of the present invention, when the initial set value of the primary resistance of the induction motor and the initial command value of the exciting current command value are given from the outside, and the exciting motor is stopped and only the exciting current is supplied, Obtain the correction value of the primary resistance of the induction motor that makes the difference between the excitation current detected from the primary current and the excitation current command zero, and add this correction value to the initial setting value of the primary resistance to obtain the setting value of the primary resistance. Obtain the correction value of the exciting current command value that makes the difference between the exciting current detected from the primary current of the induction motor and the exciting current command zero while the induction motor is rotating, and obtain the correction value. Since the exciting current command value is obtained by subtracting from the initial command value of the value, the primary resistance and the inductance set for performing the vector operation are the primary resistance and the inductance of the driven induction motor. And if different, can make the set primary resistance and the correction inductance for vector operations, there is an effect that it is possible to prevent deterioration of the speed accuracy.

According to a fourteenth aspect of the present invention, an initial set value of the primary resistance of the induction motor and an initial command value of the exciting current command value are given from the outside, the induction motor is stopped, and only the exciting current is supplied. Obtain the correction value of the primary resistance of the induction motor that makes the difference between the excitation current detected from the primary current and the excitation current command zero, and add this correction value to the initial setting value of the primary resistance to obtain the setting value of the primary resistance. Obtain the correction value of the exciting current command value that makes the difference between the exciting current detected from the primary current of the induction motor and the exciting current command zero while the induction motor is rotating, and obtain the correction value. Calculate the excitation current command value by subtracting from the initial command value
Since the setting value of the primary resistance is corrected after the excitation current command value is corrected, when the primary resistance and the inductance set for performing the vector calculation are different from the primary resistance and the inductance of the driven induction motor, the vector In addition to the function to correct the primary resistance and inductance set for calculation, the set value of the primary resistance is corrected even if the primary resistance changes with the temperature of the induction motor to prevent deterioration of speed accuracy. The effect is that you can.

According to a fifteenth aspect of the present invention, in the twelfth to fourteenth aspects of the invention, an initial set value of the secondary resistance of the induction motor is externally applied, and the primary current of the induction motor is rotated when the induction motor is rotated. Calculate the correction value of the excitation current command value that makes the difference between the excitation current detected from the excitation current command and the excitation current command zero, calculate the correction value of the secondary resistance of the induction motor from the correction value, and use this correction value as the secondary resistance. Since the setting value of the secondary resistance is calculated by adding it to the initial setting value of, the setting value of the secondary resistance that changes with the change of the excitation current command value is corrected and, for example, the slip angular frequency is estimated accordingly. By correcting the proportional constant of the induction motor used for that purpose, there is an effect that the deterioration of speed accuracy can be further reduced.

According to the sixteenth and seventeenth aspects of the present invention, the multiplication value obtained by multiplying the set value of the primary resistance and the exciting current command value, the set value of the torque current and the equivalent leakage inductor value, and the primary value The excitation component voltage is obtained from the value obtained by multiplying the frequency, and the multiplication value obtained by multiplying the setting value of the primary resistance and the torque current, the setting value of the primary inductors, and the excitation current command value The torque component voltage is obtained from the magnetic flux command value obtained by multiplying by and the multiplication value obtained by multiplying the primary frequency, and the torque current used to calculate the excitation component voltage is the torque current command value, Since the torque current used to calculate the torque component voltage is the torque current detection value or its delay value, there is an effect that the speed response when a load torque is applied can be improved.

According to the eighteenth and twentieth aspects of the present invention, the multiplication value obtained by multiplying the set value of the primary resistance and the exciting current command value, the set value of the torque current and the equivalent leakage inductor value, and the above-mentioned primary value. The excitation component voltage is obtained from the value obtained by multiplying the frequency, and the multiplication value obtained by multiplying the setting value of the primary resistance and the torque current, the setting value of the primary inductors, and the excitation current command value The magnetic flux command value obtained by multiplying by and the multiplication value obtained by multiplying the primary frequency and the torque component voltage is obtained, depending on the torque current and the primary frequency detected from the primary current, Since the torque current used to calculate the torque component voltage is switched between the torque current command value and the torque current detection value or its delay value, the rotation speed is stable regardless of the set frequency, and speed response can be improved. There is an effect that.

According to a nineteenth aspect of the present invention, in the eighteenth aspect, when the primary frequency is a low frequency, the torque current used for the torque component voltage is set as the torque current detection value or its delay value, and when the primary frequency is a high frequency, Since the torque current command value is used, there is an effect that the vibration of the torque current can be suppressed when the rotation speed of the induction motor increases. The inventions of claim 21 and claim 23 provide a multiplication value obtained by multiplying the set value of the primary resistance and the exciting current command value, the set value of the torque current and the equivalent leakage inductor value, and the primary frequency. The excitation component voltage is obtained from the value obtained by multiplying, and the multiplication value obtained by multiplying the setting value of the primary resistance and the torque current is multiplied by the setting value of the primary inductor and the excitation current command value. The torque component voltage is obtained from the product value obtained by multiplying the magnetic flux command value obtained by the above and the primary frequency, and the torque component voltage is obtained according to the primary voltage obtained from the excitation component voltage and the torque component voltage. Since the torque current used for the calculation of is switched between the torque current command value and the detected torque current value or its delay value, the rotation speed is stable regardless of the set frequency, as in the inventions of claims 18 and 20. ,
Moreover, there is an effect that the speed response can be improved.

According to a twenty-second aspect of the present invention, in the twenty-first aspect, when the primary voltage obtained from the excitation voltage component and the torque component voltage is less than a predetermined value, the torque current used for calculating the torque component voltage is set to the torque. The detected current value or its delay value is used as the torque current command value when it is equal to or more than the predetermined value. Therefore, it is possible to suppress the oscillation of the torque current when the rotation speed of the induction motor is increased.

According to the twenty-fourth and twenty-fifth aspects of the present invention, the multiplication value obtained by multiplying the set value of the primary resistance and the exciting current command value, the torque current command value and the set value of the equivalent leakage inductors value The excitation component voltage is obtained from the value obtained by multiplying the primary frequency with the value obtained by multiplying the setting value of the primary resistance by the torque current, and the setting value of the primary inductor and the excitation current. A torque component voltage is obtained from the magnetic flux command value obtained by multiplying the command value and the multiplication value obtained by multiplying the primary frequency by the primary voltage obtained from the excitation component voltage and the torque component voltage. Since the magnetic flux command value obtained by multiplying the set value of the primary inductance and the exciting current command is changed, a large load is applied in a state where the rotation speed of the induction motor is constant and the output voltage is not saturated,
When the torque current command increases, the torque component voltage increases, and the excitation component voltage increases, saturation of the primary voltage and the three-phase output voltage can be reliably detected, and the magnetic flux command value can be changed. By making it small, there is an effect that the saturation of the primary voltage V ₁ and the output voltage of the three phases can be prevented, and the deterioration of the vector control can be prevented.

In the inventions of claims 26 and 28, the product value obtained by multiplying the set value of the primary resistance and the exciting current command value, the set value of the torque current command value and the set value of the equivalent leakage inductors value, The excitation component voltage is obtained from the value obtained by multiplying the primary frequency with the value obtained by multiplying the setting value of the primary resistance by the torque current, and the setting value of the primary inductor and the excitation current. The torque component voltage is obtained from the magnetic flux command value obtained by multiplying the command value and the multiplication value obtained by multiplying the primary frequency, and the setting value of the primary inductors is multiplied by the exciting current command value. According to the magnetic flux command value obtained by changing the constant determined by the induction motor,
The difference between the actual speed estimation gain and the constant can be improved, and therefore, the rotation setting speed and the actual rotation speed match, and vector control with high speed accuracy can be achieved.

According to the twenty-seventh aspect of the invention, in the twenty-sixth aspect of the invention, since the change of the constant determined in advance by the induction motor is made gentle, the change of the estimated rotation speed is made gentle, and the vibration of the rotation speed is suppressed. There is an effect that can be.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a second embodiment.

FIG. 3 is a block diagram showing a configuration of a third embodiment.

FIG. 4 is an explanatory diagram showing a relationship between a setting error of a primary resistance and an exciting current command and an exciting current.

FIG. 5 is an explanatory diagram showing a relationship between an inductance setting error and an exciting current command and an exciting current.

FIG. 6 is an operation explanatory diagram of a switch control circuit according to a third embodiment.

FIG. 7 is an explanatory diagram of a problem of abrupt change of a rotation speed command value.

FIG. 8 is a block diagram showing a configuration of a fourth embodiment.

FIG. 9 is an explanatory diagram of a simulation result when a rotation speed command value is suddenly changed according to the fourth embodiment.

FIG. 10 is a block diagram showing a configuration of a fifth embodiment.

FIG. 11 is an explanatory diagram of a simulation result when the rotation speed command value changes abruptly according to the fifth embodiment.

FIG. 12 is an explanatory diagram of a relationship between an actual value and a set value of a torque current and a slip angular frequency, and a relationship between a rotation speed command value and an actual rotation speed.

FIG. 13 is a block diagram showing a configuration of a sixth embodiment.

FIG. 14 is an operation explanatory diagram of the sixth embodiment.

FIG. 15 is a diagram illustrating the relationship between the actual value and the set value of the torque current and the slip angular frequency and the relationship between the rotation speed command value and the actual rotation speed according to the sixth embodiment.

FIG. 16 is a block diagram showing the configuration of the seventh embodiment.

FIG. 17 is a block diagram showing a configuration of an eighth embodiment.

FIG. 18 is a block diagram showing the configuration of the ninth embodiment.

FIG. 19 is a block diagram showing the configuration of the tenth embodiment.

FIG. 20 is a block diagram showing the structure of an eleventh embodiment.

FIG. 21 is a block diagram showing the structure of a twelfth embodiment.

FIG. 22 is a block diagram showing the structure of the thirteenth embodiment.

FIG. 23 is a schematic circuit diagram of a main circuit of an inverter.

FIG. 24 is a block diagram showing the configuration of the fourteenth embodiment.

FIG. 25 is a block diagram showing the structure of a fifteenth embodiment.

FIG. 26 is a block diagram showing the structure of the sixteenth embodiment.

[Explanation of symbols]

 1 Vector Operation Unit 2,6 Coordinate Converter 3 Inverter 4 Induction Motor 5 Current Detector 11 Speed Controller 7,12 Multiplier 8,10,15 Subtractor 9,13,29 Adder 16 Current Controller

Claims (28)

[Claims] 1. An induction motor driven by a voltage source inverter,
While obtaining the command voltage value of the voltage-source inverter from the excitation voltage component and the torque component voltage of the induction motor, the torque current and the excitation current detected from the primary current of the induction motor and the primary frequency and the voltage depending on these command values. Is used in the vector controller of the induction motor to be controlled, the slip angle frequency is estimated by multiplying the torque current detected from the primary current by a constant determined in advance by the induction motor,
The estimated value of the slip angular frequency is subtracted from the slip angular frequency command value, the subtracted value is added to the given speed command value to obtain the estimated value of the rotational speed of the induction motor, and the estimated speed value and the speed command are calculated. The torque current command value is obtained based on the difference with the value, the torque current command value is multiplied by the constant obtained from the constant of the induction motor to obtain the slip angular frequency command value, and the slip angular frequency command value and A vector control method for an induction motor, comprising: adding the speed command value to obtain a primary frequency. 2. An induction motor driven by a voltage source inverter,
While obtaining the command voltage value of the voltage-source inverter from the excitation voltage component and the torque component voltage of the induction motor, the torque current and the excitation current detected from the primary current of the induction motor and the primary frequency and the voltage depending on these command values. In the vector controller of the induction motor in which is controlled, the detection means for detecting the torque current from the primary current, and the slip angular frequency by multiplying the torque current value detected by the detection means by a constant predetermined in the induction motor. And a subtracting means for subtracting the estimated value of the slip angular frequency obtained by the estimating means from the slip angular frequency command value, and a subtraction value obtained by the subtracting means and a given speed command value. First, the estimated value of the rotation speed of the induction motor is obtained.
Means for obtaining the torque current command value based on the difference between the speed estimated value obtained by the first adding means and the speed command value, and the induction for the torque current command value obtained by this means. A multiplication means for obtaining the slip angular frequency command value by multiplying the constant obtained from the electric motor constant, and a slip frequency angular command value obtained by the multiplication means and the speed command value are added to obtain a primary frequency. And a vector control device for an induction motor, comprising: 3. An induction motor is driven by a voltage source inverter,
While obtaining the command voltage value of the voltage-source inverter from the excitation voltage component and the torque component voltage of the induction motor, the torque current and the excitation current detected from the primary current of the induction motor and the primary frequency and the voltage depending on these command values. Is used in the vector controller of the induction motor to be controlled, the torque current detected from the primary current is subtracted from the torque current command, the subtraction value is multiplied by a constant determined in advance, and the multiplication value is given. The estimated value of the rotation speed of the induction motor is obtained by adding it to the speed command value, and the torque current command value is obtained based on the difference between the speed estimate value and the speed command value. The slip angular frequency command value is obtained by multiplying the constant obtained from the constant of the induction motor, and the slip angular frequency command and the speed command value are added to obtain the slip angular frequency command value. Vector control method for an induction motor and obtains the frequency. 4. An induction motor driven by a voltage source inverter,
While obtaining the command voltage value of the voltage-source inverter from the excitation voltage component and the torque component voltage of the induction motor, the torque current and the excitation current detected from the primary current of the induction motor and the primary frequency and the voltage depending on these command values. In the vector control device for an induction motor in which the above-mentioned control is performed, detection means for detecting the torque current from the primary current, subtraction means for subtracting the torque current value detected by the detection means from the torque current command value, and this subtraction means Multiplying means for multiplying the subtracted value obtained in step 1 by a constant determined in advance by an induction motor,
First adding means for adding the multiplication value of the multiplying means to a given speed command value to obtain an estimated value of the rotational speed of the induction motor, and the speed estimated value obtained by the first adding means and the speed instruction. Means for obtaining the torque current command value based on the difference from the value and multiplying means for obtaining the slip angular frequency command value by multiplying the torque current command value obtained by this means by a constant obtained from the constant of the induction motor And a second adding means for adding the slip angular frequency command obtained by the multiplying means and the speed command value to obtain a primary frequency. 5. An induction motor is driven by a voltage source inverter,
While obtaining the command voltage value of the voltage-source inverter from the excitation voltage component and the torque component voltage of the induction motor, the torque current and the excitation current detected from the primary current of the induction motor and the primary frequency and the voltage depending on these command values. Is used in the vector controller of the induction motor that is controlled, the slip angular frequency is estimated by multiplying the torque current by a constant determined in advance by the induction motor, and the estimated value of the slip angular frequency is calculated from the slip angular frequency command value. Subtract and add the subtracted value to the given speed command value to obtain the estimated value of the rotational speed of the induction motor, and obtain the torque current command value based on the difference between the speed estimated value and the speed command value. This torque current command value is multiplied by the constant obtained from the constant of the induction motor to obtain the slip angular frequency command value, and this slip angular frequency command value Vector control method for an induction motor and obtains a primary frequency by adding the above estimated speed value. 6. An induction motor driven by a voltage source inverter,
While obtaining the command voltage value of the voltage-source inverter from the excitation voltage component and the torque component voltage of the induction motor, the torque current and the excitation current detected from the primary current of the induction motor and the primary frequency and the voltage depending on these command values. In the vector control device of the induction motor, the detection means for detecting the torque current from the primary current and the torque current value detected by the detection means are multiplied by a constant determined in advance by the induction motor to obtain a slip angle. An estimating means for estimating the frequency, a subtracting means for subtracting the estimated value of the slip angular frequency obtained by the estimating means from the slip angular frequency command value, and a subtraction value obtained by the subtracting means and a given speed command value are added. First adding means for obtaining an estimated value of the rotational speed of the induction motor, and the estimated speed value obtained by the first adding means and the speed finger. Means for obtaining the torque current command value based on the difference from the value, and multiplication for obtaining the slip angular frequency command value by multiplying the torque current command value obtained by this means by the constant obtained from the constant of the induction motor A vector control device for an induction motor, comprising: means and second adding means for adding the slip angular frequency command value obtained by the multiplying means and the speed estimation value to obtain a primary frequency. 7. An induction motor driven by a voltage source inverter,
While obtaining the command voltage value of the voltage-source inverter from the excitation voltage component and the torque component voltage of the induction motor, the torque current and the excitation current detected from the primary current of the induction motor and the primary frequency and the voltage depending on these command values. Is used in the vector controller of the induction motor to be controlled, the slip angle frequency is estimated by multiplying the torque current detected from the primary current by a constant determined in advance by the induction motor,
The estimated value of the slip angular frequency is subtracted from the slip angular frequency command value, the subtracted value is added to the given speed command value to obtain the estimated value of the rotational speed of the induction motor, and the estimated speed value and the speed command are calculated. The torque current command value is obtained based on the difference between the value and the torque current command value, and the slip angular frequency command value is obtained by multiplying the constant obtained from the constant of the induction motor by the slip angular frequency command value. A vector control method for an induction motor, characterized in that a primary frequency is obtained by adding a deviation between the slip angular frequency command and the slip angular frequency estimated value to an added value obtained by adding the speed command value. 8. An induction motor driven by a voltage source inverter,
While obtaining the command voltage value of the voltage-source inverter from the excitation voltage component and the torque component voltage of the induction motor, the torque current and the excitation current detected from the primary current of the induction motor and the primary frequency and the voltage depending on these command values. In the vector control device of the induction motor, the detection means for detecting the torque current from the primary current and the torque current value detected by the detection means are multiplied by a constant determined in advance by the induction motor to obtain a slip angle. An estimating means for estimating the frequency, a subtracting means for subtracting the estimated value of the slip angular frequency obtained by the estimating means from the slip angular frequency command value, and a subtraction value obtained by the subtracting means and a given speed command value are added. First adding means for obtaining an estimated value of the rotational speed of the induction motor, and the estimated speed value obtained by the first adding means and the speed finger. Means for obtaining the torque current command value based on the difference from the value, and multiplication for obtaining the slip angular frequency command value by multiplying the torque current command value obtained by this means by the constant obtained from the constant of the induction motor Means, second adding means for adding the slip angular frequency command value and the speed command value obtained by the multiplying means, and means for obtaining a deviation between the slip angular frequency command value and the slip angular frequency estimated value. A vector control device for an induction motor, comprising: means for adding the deviation value obtained by this means to the value obtained by the second adding means to obtain a primary frequency. 9. An induction motor is driven by a voltage source inverter,
While obtaining the command voltage value of the voltage-source inverter from the excitation voltage component and the torque component voltage of the induction motor, the torque current and the excitation current detected from the primary current of the induction motor and the primary frequency and the voltage depending on these command values. Is used in the vector controller of the induction motor to be controlled, the value obtained by delaying the torque current is multiplied by a constant determined in advance by the induction motor, and the product of the multiplied value and the speed command value given is added to the primary frequency. A vector control method for an induction motor, characterized by: 10. The vector control method for an induction motor according to claim 9, wherein the delay value of the torque current is changed based on the difference between the torque current value and the delay value of the torque current. 11. An induction motor is driven by a voltage source inverter, a command voltage value of the voltage source inverter is obtained from an excitation voltage and a torque component voltage of the induction motor, and a torque detected from a primary current of the induction motor. In the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the current and the exciting current and these command values,
Detecting means for detecting the torque current from the primary current, means for delaying the detected torque current, and multiplying means for multiplying the delay value of the torque current obtained by delaying by this means by a constant predetermined in the induction motor. And a vector control device for an induction motor, comprising: a means for adding a multiplication value obtained by the multiplication means and a given speed command value to obtain a primary frequency. 12. An induction motor is driven by a voltage source inverter, a command voltage value of the voltage source inverter is obtained from an excitation voltage component and a torque component voltage of the induction motor, and a torque detected from a primary current of the induction motor component. It is used in the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the current and the exciting current and their command values, so as to eliminate the difference between the exciting current detected from the primary current and the exciting current command value. A vector control method for an induction motor, which comprises correcting an exciting current command value. 13. An induction motor is driven by a voltage source inverter, a command voltage value of the voltage source inverter is obtained from an excitation voltage and a torque component voltage of the induction motor, and a torque detected from a primary current of the induction motor. Used for vector control device of induction motor whose primary frequency and the above voltage are controlled by current and exciting current and these command values, the initial setting value of the primary resistance of induction motor and the initial command value of exciting current command value are externally applied. Given, in a state in which the induction motor is stopped and only the excitation current is supplied, the correction value of the primary resistance of the induction motor that makes the difference between the excitation current detected from the primary current of the induction motor and the excitation current command zero is obtained, Add the correction value to the initial setting value of the primary resistance to obtain the setting value of the primary resistance, and from the primary current of the induction motor, rotate the induction motor. Obtains a correction value of the excitation current command value to zero the difference between the excitation current and the exciting current command issued, by subtracting the correction value from the initial command value of the exciting current command value,
A vector control method for an induction motor, characterized by obtaining an exciting current command value. 14. An induction motor is driven by a voltage source inverter, a command voltage value of the voltage source inverter is obtained from the excitation voltage component and the torque component voltage of the induction motor, and the torque detected from the primary current of the induction motor. Used for vector control device of induction motor whose primary frequency and the above voltage are controlled by current and exciting current and these command values, the initial setting value of the primary resistance of induction motor and the initial command value of exciting current command value are externally applied. Given, in a state in which the induction motor is stopped and only the excitation current is supplied, the correction value of the primary resistance of the induction motor that makes the difference between the excitation current detected from the primary current of the induction motor and the excitation current command zero is obtained, Add the correction value to the initial setting value of the primary resistance to obtain the setting value of the primary resistance, and from the primary current of the induction motor, rotate the induction motor. Obtains a correction value of the excitation current command value to zero the difference between the excitation current and the exciting current command issued, by subtracting the correction value from the initial command value of the exciting current command value,
A vector control method for an induction motor, comprising: determining an exciting current command value; and correcting the set value of the primary resistance after correcting the exciting current command value. 15. A difference between an exciting current detected from a primary current of the induction motor and an exciting current command is set to zero when an initial setting value of a secondary resistance of the induction motor is externally applied and the induction motor is rotated. Calculate the correction value of the exciting current command value
Obtain the correction value of the secondary resistance of the induction motor from the correction value,
15. The vector control method for an induction motor according to claim 12, wherein the correction value is added to the initial setting value of the secondary resistance to obtain the setting value of the secondary resistance. 16. An induction motor is driven by a voltage source inverter, and a command voltage value for the voltage source inverter is obtained from the excitation voltage component and torque component voltage of the induction motor, and the torque detected from the primary current of the induction motor component. Used in the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the current and the exciting current and these command values, and the multiplication value obtained by multiplying the set value of the primary resistance and the exciting current command value , The excitation voltage is obtained from the value obtained by multiplying the set value of the torque current and the equivalent leakage inductor value by the primary frequency, and is obtained by multiplying the set value of the primary resistance by the torque current. The torque component voltage is calculated from the multiplied value, the magnetic flux command value obtained by multiplying the set value of the primary inductors and the exciting current command value, and the multiplied value obtained by multiplying the above primary frequency. Vector control of an induction motor characterized in that the torque current used to calculate and calculate the excitation voltage is the torque current command value, and the torque current used to calculate the torque voltage is the torque current detection value or its delay value. Method. 17. An induction motor is driven by a voltage source inverter, a command voltage value of the voltage source inverter is obtained from an excitation voltage component and a torque component voltage of the induction motor, and a torque detected from a primary current of the induction motor component. In the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the current and the exciting current and these command values,
Detecting means for detecting the torque current from the primary current, first multiplying means for multiplying the set value of the primary resistance and the exciting current command value, the set value of the torque current and the equivalent leakage inductor value, and the primary frequency A second multiplication means for multiplying by, a first calculation means for obtaining an excitation voltage from the multiplication values of the first and second multiplication means, and a first multiplication means for multiplying the set value of the primary resistance by the torque current. 3 multiplying means, a fourth multiplying means for obtaining a magnetic flux command value by multiplying the set value of the primary inductor and the exciting current command value, the magnetic flux command value obtained by the fourth multiplying means, and the primary frequency. A fifth multiplication means for multiplying by
The second calculation means for obtaining the torque component voltage from the multiplication values of the third and fifth multiplication means is provided, and the torque current used for the calculation of the excitation component voltage is used as the torque current command value to calculate the torque component voltage. A vector control device for an induction motor, wherein the torque current to be used is a torque current detection value or a delay value thereof. 18. An induction motor is driven by a voltage source inverter, a command voltage value of the voltage source inverter is obtained from an excitation voltage component and a torque component voltage of the induction motor, and a torque detected from a primary current of the induction motor component. Used in the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the current and the exciting current and these command values, and the multiplication value obtained by multiplying the set value of the primary resistance and the exciting current command value , The excitation voltage is obtained from the value obtained by multiplying the set value of the torque current and the equivalent leakage inductor value by the primary frequency, and is obtained by multiplying the set value of the primary resistance by the torque current. The torque component voltage is calculated from the multiplied value, the magnetic flux command value obtained by multiplying the set value of the primary inductors and the exciting current command value, and the multiplied value obtained by multiplying the above primary frequency. Obtained, according to the torque current detected from the primary current and the primary frequency, the torque current used in the calculation of the torque component voltage is switched to the torque current command value and the torque current detection value or its delay value. Vector control method for induction motor. 19. When the primary frequency is a low frequency, the torque current used for the torque component voltage is used as the torque current detection value or its delay value, and when it is a high frequency, the torque current command value is used. The vector control method for an induction motor according to claim 18. 20. An induction motor is driven by a voltage source inverter, and a command voltage value for the voltage source inverter is obtained from the excitation voltage component and the torque component voltage of the induction motor, and the torque detected from the primary current of the induction motor component. In the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the current and the exciting current and these command values,
Detecting means for detecting the torque current from the primary current, first multiplying means for multiplying the set value of the primary resistance and the exciting current command value, the set value of the torque current and the equivalent leakage inductor value, and the primary frequency A second multiplication means for multiplying by, a first calculation means for obtaining an excitation voltage from the multiplication values of the first and second multiplication means, and a first multiplication means for multiplying the set value of the primary resistance by the torque current. 3 multiplying means, a fourth multiplying means for obtaining a magnetic flux command value by multiplying the set value of the primary inductor and the exciting current command value, the magnetic flux command value obtained by the fourth multiplying means, and the primary frequency. A fifth multiplication means for multiplying by
It is used for calculating the torque component voltage according to the second computing device for obtaining the torque component voltage from the multiplication values of the third and fifth multiplication devices, and the torque current detected from the primary current and the primary frequency. A vector control device for an induction motor, comprising: means for switching a torque current between a torque current command value and a torque current detection value or a delay value thereof. 21. An induction motor is driven by a voltage source inverter, a command voltage value of the voltage source inverter is obtained from an excitation voltage component and a torque component voltage of the induction motor, and a torque detected from a primary current of the induction motor component. Used in the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the current and the exciting current and these command values, and the multiplication value obtained by multiplying the set value of the primary resistance and the exciting current command value , The excitation voltage is obtained from the value obtained by multiplying the set value of the torque current and the equivalent leakage inductor value by the primary frequency, and is obtained by multiplying the set value of the primary resistance by the torque current. The torque component voltage is calculated from the multiplied value, the magnetic flux command value obtained by multiplying the set value of the primary inductors and the exciting current command value, and the multiplied value obtained by multiplying the above primary frequency. According to the primary voltage obtained from the excitation voltage and the torque voltage, the torque current used to calculate the torque voltage is switched between the torque current command value and the torque current detection value or its delay value. Vector control method for induction motor. 22. When the primary voltage obtained from the excitation voltage component and the torque component voltage is less than a predetermined value, the torque current used for calculating the torque component voltage is set as the torque current detection value or its delay value, and the predetermined value is set. 22. The vector control method for an induction motor according to claim 21, wherein the torque current command value is used when the value is greater than or equal to the value. 23. An induction motor is driven by a voltage source inverter, and a command voltage value for the voltage source inverter is obtained from the excitation voltage component and the torque component voltage of the induction motor, and the torque detected from the primary current of the induction motor component. In the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the current and the exciting current and these command values,
Detecting means for detecting the torque current from the primary current, first multiplying means for multiplying the set value of the primary resistance and the exciting current command value, the set value of the torque current and the equivalent leakage inductor value, and the primary frequency A second multiplication means for multiplying by, a first calculation means for obtaining an excitation voltage from the multiplication values of the first and second multiplication means, and a first multiplication means for multiplying the set value of the primary resistance by the torque current. 3 multiplying means, a fourth multiplying means for obtaining a magnetic flux command value by multiplying the set value of the primary inductor and the exciting current command value, the magnetic flux command value obtained by the fourth multiplying means, and the primary frequency. A fifth multiplication means for multiplying by
It is used to calculate the torque component voltage according to the second computing device that obtains the torque component voltage from the multiplication values of the third and fifth multiplication devices and the primary voltage that is obtained from the excitation component voltage and the torque component voltage. A vector control device for an induction motor, comprising means for switching a torque current between a torque current command value and a detected torque current value or a delay value thereof. 24. An induction motor is driven by a voltage source inverter, a command voltage value of the voltage source inverter is obtained from the excitation voltage component and torque component voltage of the induction motor, and the torque detected from the primary current of the induction motor component. Used in the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the current and the exciting current and these command values, and the multiplication value obtained by multiplying the set value of the primary resistance and the exciting current command value , The excitation voltage is obtained from the value obtained by multiplying the torque current command value, the set value of the equivalent leakage inductors value, and the primary frequency, and is obtained by multiplying the set value of the primary resistance by the torque current. Torque from the obtained multiplication value, the magnetic flux command value obtained by multiplying the set value of the primary inductors and the exciting current command value, and the multiplied value obtained by multiplying the above-mentioned primary frequency. The voltage is obtained, and the magnetic flux command value obtained by multiplying the setting value of the primary inductance and the exciting current command by the primary voltage obtained from the excitation voltage component and the torque component voltage is changed. Vector control method. 25. The induction motor is driven by a voltage source inverter, a command voltage value of the voltage source inverter is obtained from the excitation voltage component and the torque component voltage of the induction motor, and the torque detected from the primary current of the induction motor component. In the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the current and the exciting current and these command values,
Detecting means for detecting the torque current from the primary current, first multiplying means for multiplying the set value of the primary resistance and the exciting current command value, the set value of the torque current and the equivalent leakage inductor value, and the primary frequency A second multiplication means for multiplying by, a first calculation means for obtaining an excitation voltage from the multiplication values of the first and second multiplication means, and a first multiplication means for multiplying the set value of the primary resistance by the torque current. 3 multiplying means, a fourth multiplying means for obtaining a magnetic flux command value by multiplying the set value of the primary inductor and the exciting current command value, the magnetic flux command value obtained by the fourth multiplying means, and the primary frequency. A fifth multiplication means for multiplying by
By the second calculating means for obtaining the torque component voltage from the multiplication values of the third and fifth multiplying means and the primary voltage obtained from the excitation component voltage and the torque component voltage, the set value of the primary inductance and the excitation current command are obtained. And a means for changing a magnetic flux command value obtained by multiplying by the vector controller for an induction motor. 26. The induction motor is driven by a voltage source inverter, and a command voltage value for the voltage source inverter is obtained from the excitation voltage component and the torque component voltage of the induction motor, and the torque detected from the primary current of the induction motor component. Used in the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the current and the exciting current and these command values, and the multiplication value obtained by multiplying the set value of the primary resistance and the exciting current command value , The excitation voltage is obtained from the value obtained by multiplying the torque current command value, the set value of the equivalent leakage inductors value, and the primary frequency, and is obtained by multiplying the set value of the primary resistance by the torque current. Torque from the obtained multiplication value, the magnetic flux command value obtained by multiplying the set value of the primary inductors and the exciting current command value, and the multiplied value obtained by multiplying the above-mentioned primary frequency. Vector control of an induction motor characterized by changing the constant determined by the induction motor according to the magnetic flux command value obtained by obtaining the voltage and multiplying the set value of the primary inductors and the exciting current command value Method. 27. The vector control method for an induction motor according to claim 26, wherein a change in a constant determined in advance by the induction motor is moderated. 28. An induction motor is driven by a voltage source inverter, a command voltage value of the voltage source inverter is obtained from an excitation voltage component and a torque component voltage of the induction motor component, and a torque detected from the primary current of the induction motor component. In the vector controller of the induction motor in which the primary frequency and the voltage are controlled by the current and the exciting current and these command values,
Detecting means for detecting the torque current from the primary current, first multiplying means for multiplying the set value of the primary resistance and the exciting current command value, the set value of the torque current and the equivalent leakage inductor value, and the primary frequency A second multiplication means for multiplying by, a first calculation means for obtaining an excitation voltage from the multiplication values of the first and second multiplication means, and a first multiplication means for multiplying the set value of the primary resistance by the torque current. 3 multiplying means, a fourth multiplying means for obtaining a magnetic flux command value by multiplying the set value of the primary inductor and the exciting current command value, the magnetic flux command value obtained by the fourth multiplying means, and the primary frequency. A fifth multiplication means for multiplying by
Depending on the second calculation means for obtaining the torque component voltage from the multiplication values of the third and fifth multiplication means, and the magnetic flux command value obtained by multiplying the set value of the primary inductors and the exciting current command value. And a means for changing a constant determined by the induction motor, the vector control device for the induction motor.