Control apparatus of induction motor

Claim 2

A control apparatus of an induction motor, comprising: a detector for detecting a primary current of the induction motor; primary current component detecting means for detecting an exciting current and a torque current from the current detected by the detector; correcting means for outputting a correction voltage to set to zero a difference between an exciting current command value and the exciting current outputted from the primary current detecting means; frequency-voltage control means for outputting a frequency command and a voltage command based on an output of the correcting means, and an inductance ratio of the induction motor, the inductance ratio being a ratio of a mutual inductance of the inductance motor to a secondary self-inductance of the induction motor; and constant correcting means for correcting the inductance ratio used by the frequency-voltage control means to set to zero the output of the correcting means; wherein the frequency-voltage control means outputs a frequency command and a voltage command based on a constant obtained from a primary resistance of the induction motor, the inductance ratio of the induction motor, a leakage inductance of the induction motor, and a preset value; and wherein the constant correcting means corrects the constant.

Claim 3

A control apparatus of an induction motor, comprising: a detector for detecting a primary current of the induction motor; primary current component detecting means for detecting an exciting current and a torque current from the current detected by the detector; correcting means for outputting a correction voltage to set to zero a difference between an exciting current command value and the exciting current outputted from the primary current detecting means; frequency-voltage control means for outputting a frequency command and a voltage command based on an output of the correcting means, a primary resistance of the induction motor, a leakage inductance of the induction motor, and an inductance ratio of the induction motor, the inductance ratio being a ratio of a mutual inductance of the induction motor to a secondary self-inductance of the induction motor; and at least one constant correcting means selected from a first constant correcting means, a second constant correcting means, and a third constant correcting means, the first constant correcting means being for correcting the primary resistance based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the primary resistance, the second constant correcting means being for correcting the leakage inductance based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the leakage inductance, and the third constant correcting means being for correcting the inductance ratio based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the inductance ratio.

Claim 4

A control apparatus of an induction motor, comprising: a detector for detecting a primary current of the induction motor; primary current component detecting means for detecting an exciting current and a torque current from the current detected by the detector; correcting means for outputting a correction voltage to set to zero a difference between an exciting current command value and the exciting current outputted from the primary current detecting means; frequency-voltage control means for outputting a frequency command and a voltage command based on an output of the correcting means, a primary resistance of the induction motor, a leakage inductance of the induction motor, and an inductance ratio of the induction motor, the inductance ratio being a ratio of a mutual inductance of the induction motor to a secondary self-inductance of the induction motor; and at least one constant correcting means selected from a first constant correcting means, a second constant correcting means, and a third constant correcting means, the first constant correcting means being for correcting the primary resistance based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the primary resistance, the second constant correcting means being for correcting the leakage inductance based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the leakage inductance, and the third constant correcting means being for correcting the inductance ratio based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the inductance ratio.

Claim 5

A control apparatus of an induction motor, comprising: a detector for detecting a primary current of the induction motor; primary current component detecting means for detecting an exciting current and a torque current from the current detected by the detector; correcting means for outputting a correction voltage to set to zero a difference between an exciting current command value and the exciting current outputted from the primary current detecting means; frequency-voltage control means for outputting a frequency command and a voltage command based on an output of the correcting means, a primary resistance of the induction motor, a leakage inductance of the induction motor, and an inductance ratio of the induction motor, the inductance ratio being a ratio of a mutual inductance of the induction motor to a secondary self-inductance of the induction motor; and at least one constant correcting means selected from a first constant correcting means, a second constant correcting means, and a third constant correcting means, the first constant correcting means being for correcting the primary resistance based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the primary resistance, the second constant correcting means being for correcting the leakage inductance based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the leakage inductance, and the third constant correcting means being for correcting the inductance ratio based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the inductance ratio; wherein the frequency-voltage control means outputs a frequency command and a voltage command based on a constant obtained by an arithmetic operation from the primary resistance, the inductance ratio, the leakage inductance, and a preset value; and wherein the second constant correcting means corrects the constant based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the constant.

Claim 6

A control apparatus of an induction motor, comprising: a detector for detecting a primary current of the induction motor; primary current component detecting means for detecting an exciting current and a torque current from the current detected by the detector; correcting means for outputting a correction voltage to set to zero a difference between an exciting current command value and the exciting current outputted from the primary current detecting means; frequency-voltage control means for outputting a frequency command and a voltage command based on an output of the correcting means, a primary resistance of the induction motor, a leakage inductance of the induction motor, and an inductance ratio of the induction motor, the inductance ratio being a ratio of a mutual inductance of the induction motor to a secondary self-inductance of the induction motor; and at least one constant correcting means selected from a first constant correcting means, a second constant correcting means, and a third constant correcting means, the first constant correcting means being for correcting the primary resistance based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the primary resistance, the second constant correcting means being for correcting the leakage inductance based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the leakage inductance, and the third constant correcting means being for correcting the inductance ratio based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the inductance ratio; wherein the frequency-voltage control means outputs a frequency command and a voltage command based on a constant obtained by an arithmetic operation from the primary resistance, the inductance ratio, the leakage inductance, and a preset value; and wherein the second constant correcting means corrects the constant based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the constant.

Claim 7

A control apparatus of an induction motor, comprising: a detector for detecting a primary current of the induction motor; primary current component detecting means for detecting an exciting current and a torque current from the current detected by the detector; correcting means for outputting a correction voltage to set to zero a difference between an exciting current command value and the exciting current outputted from the primary current detecting means; frequency-voltage control means for outputting a frequency command and a voltage command based on an output of the correcting means, a primary resistance of the induction motor, a leakage inductance of the induction motor, and a primary self-inductance of the induction motor; and at least one constant correcting means selected from a first constant correcting means, a second constant correcting means, and a third constant correcting means, the first constant correcting means being for correcting the primary resistance based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the primary resistance, the second constant correcting means being for correcting the leakage inductance based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the leakage inductance, and the third constant correcting means being for correcting the primary self-inductance based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the primary self-inductance.

Claim 8

A control apparatus of an induction motor, comprising: a detector for detecting a primary current of the induction motor; primary current component detecting means for detecting an exciting current and a torque current from the current detected by the detector; correcting means for outputting a correction voltage to set to zero a difference between an exciting current command value and the exciting current outputted from the primary current detecting means; frequency-voltage control means for outputting a frequency command and a voltage command based on an output of the correcting means, a primary resistance of the induction motor, a leakage inductance of the induction motor, and a primary self-inductance of the induction motor; and at least one constant correcting means selected from a first constant correcting means, a second constant correcting means, and a third constant correcting means, the first constant correcting means being for correcting the primary resistance based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the primary resistance, the second constant correcting means being for correcting the leakage inductance based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the leakage inductance, and the third constant correcting means being for correcting the primary self-inductance based on a quantity obtained by multiplying a quantity of the voltage command outputted from the frequency-voltage control means by the output of the correcting means, the quantity of the voltage command being a result of partial differentiation with the primary self-inductance.

Claim 9

A control apparatus of an induction motor, comprising: a detector for detecting a primary current of the induction motor; primary current component detecting means for detecting an exciting current and a torque current from the current detected by the detector; correcting means for outputting a correction voltage to set to zero a difference between an exciting current command value and the exciting current outputted from the primary current detecting means; frequency-voltage control means for outputting a frequency command and a voltage command based at least on one of (1) an output of the correcting means, a primary resistance of the induction motor, a leakage inductance of the induction motor, and an inductance ratio of the induction motor, the induction ratio being a ratio of a mutual inductance of the induction motor to a secondary self-inductance of the induction motor, and (2) a constant replacing at least one of the primary resistance, the leakage inductance, and the inductance ratio, the constant being obtained by a calculation from the primary resistance, the leakage inductance, the inductance ratio, and a preset value; and constant correcting means for correcting the constant for use in the frequency-voltage control means to set to zero the correction voltage output by the correcting means.

Claim 10

A control apparatus of an induction motor, comprising: a detector for detecting a primary current of the induction motor; primary current component detecting means for detecting an exciting current and a torque current from the current detected by the detector; correcting means for outputting a correction voltage to set to zero a difference between an exciting current command value and the exciting current outputted from the primary current detecting means; frequency-voltage control means for outputting a frequency command and a voltage command based at least on one of (1) an output of the correcting means, a primary resistance of the induction motor, a leakage inductance of the induction motor, and an inductance ratio of the induction motor, the induction ratio being a ratio of a mutual inductance of the induction motor to a secondary self-inductance of the induction motor, and (2) a constant replacing at least one of the primary resistance, the leakage inductance, and the inductance ratio, the constant being obtained by a calculation from the primary resistance, the leakage inductance, the inductance ratio, and a preset value; and constant correcting means for correcting the constant for use in the frequency-voltage control means to set to zero the correction voltage output by the correcting means.