JP6021145B2 - Induction machine controller - Google Patents

Description

  The present invention relates to an induction machine control device that enables smooth speed estimation even when there is a residual magnetic flux when starting up an induction machine.

  FIG. 2 is a block diagram showing a conventional example. 1 is an induction machine, 2 is a voltage detector, 3 is a current detector, 4 is a power converter, 5 is a current control means, 6 is a control command creation means, 7 is a speed calculation means, 8 is a preliminary excitation calculation means, 9 Is an initial speed calculating means, 10 is a control switching means, 11 is a voltage switching means, and 12 is a control switching signal generator.

  The power converter 4 receives the voltage command V * from the voltage switching means 11 and distributes power to the induction machine 1.

  The voltage detector 2 detects the input voltage v input to the induction machine 1.

  The current detector 3 detects the input current i input to the induction machine 1.

The control switching signal generator 12 receives the speed command ω _m * and outputs a control switching signal CH. The control switching signal CH becomes 1 at the time of starting, becomes 2 after a predetermined time when the preliminary excitation calculation means 8 calculates the speed command ω _m * of the preliminary excitation calculation means 8, and the secondary magnetic flux Ψ ₂ of the initial speed calculation means 12 becomes the speed. It becomes 0 after the speed command ω _m * of the initial speed calculation means 12 is made to follow the actual speed to a size that can be calculated.

ここで、Ｒ₁は誘導機1の一次抵抗、Ｌ_σはL₁−M²/Ｌ₂、Ｌ₁は誘導機1の一次自己インダクタンス、Ｌ₂は誘導機1の二次自己インダクタンス、Ｍは誘導機1の相互インダクタンス、pはd/dt 、i_α、i_βは入力電流iのα、β成分、v_α、v_βは電圧指令V*のα、β成分である。所定時間後の二次磁束Ψ₂のベクトルの回転角θを所定時間で除することで予備励磁演算手段8の演算速度ω₁₁を求める。予備励磁演算手段8の演算二次磁束Ψ₂₁は式(3)で演算する。

ここで、Ｔ₂は誘導機1の二次時定数であり、jは虚数単位である。式(3)の第2項は円軌跡を描く項であり、式(1)と式(2)により所定時間後の第2項のベクトルと予備励磁演算手段8の演算速度ω₁₁が求められると、第1項も求められるため、所定時間後の予備励磁演算手段8の演算二次磁束Ψ₂₁を演算できる。 The pre-excitation calculation means 8 inputs the voltage command V * and the input current i, the voltage command V ₁ of the pre-excitation calculation means 8, the calculation speed ω ₁₁ of the pre-excitation calculation means 8, and the calculation of the pre-excitation calculation means 8 The next magnetic flux Ψ ₂₁ is output. When the control switching signal CH is 1, the pre-excitation calculation means that outputs from the voltage command V * of the induction machine 1 and the input current i to the voltage switching means 11 in which the input current i of the induction machine 1 becomes a predetermined DC current i _dx Calculate the α component ψ _2α and β component ψ _2β of the secondary magnetic flux Ψ ₂ to calculate the voltage V ₁ of 8 and the calculation speed ω ₁₁ of the pre-excitation calculation means 8 using the expressions (1) and (2). To do.

Here, R ₁ is the primary resistance of induction machine 1, L _σ is L ₁ −M ² / L ₂ , L ₁ is the primary self inductance of induction machine 1, L ₂ is the secondary self inductance of induction machine 1, and M is The mutual inductance of the induction machine 1, p is d / dt, i _α , i _β are α and β components of the input current i, and v _α and v _β are α and β components of the voltage command V *. The calculation speed ω ₁₁ of the preliminary excitation calculation means 8 is obtained by dividing the rotation angle θ of the vector of the secondary magnetic flux Ψ ₂ after a predetermined time by the predetermined time. The calculation secondary magnetic flux Ψ ₂₁ of the pre-excitation calculation means 8 is calculated by Expression (3).

Here, T ₂ is a secondary time constant of the induction machine 1 and j is an imaginary unit. The second term in equation (3) is a term that draws a circular locus, and the equation (1) and equation (2) determine the vector of the second term after a predetermined time and the calculation speed ω ₁₁ of the pre-excitation calculation means 8. Since the first term is also obtained, the calculated secondary magnetic flux Ψ ₂₁ of the pre-excitation calculating means 8 after a predetermined time can be calculated.

ここでk_gは速度ゲイン、Ψ_2α、Ψ_2βは二次磁束Ψ₂のα、β成分である。この時、トルク指令を0で制御した時、演算速度と実速度に誤差があると演算トルクが0にならないことを利用し、演算トルクに比例する式(2)の括弧の中の値が0になるように初期速度演算手段9の演算速度ω₁₂を演算する。 The initial speed calculation means 9 receives the voltage command V *, the input current i and the calculation secondary magnetic flux Ψ ₂₁ of the preliminary excitation calculation means 8 and outputs the calculation speed ω ₁₂ of the initial speed calculation means 9. After the pre-excitation calculation, in order to make the calculation speed follow the actual speed until the magnetic flux becomes a size that can be calculated, when the control switching signal CH is 2, ω ₁₁ of the pre-excitation calculation means 8 and the pre-excitation calculation means 8 Using the calculated secondary magnetic flux Ψ ₂₁ as an initial value, the secondary magnetic flux Ψ ₂ is calculated from the voltage command V * and the input current i of the induction machine 1 using the expressions (1) and (2), and the input of the induction machine 1 From the current i and the secondary magnetic flux Ψ ₂ , the calculation speed ω ₁₂ of the initial speed calculation means 9 output to the control switching means 10 is calculated by the equation (4).

Here, k _g is a speed gain, and ψ _2α and ψ _2β are α and β components of the secondary magnetic flux ψ ₂ . At this time, when the torque command is controlled at 0, using the fact that the calculated torque does not become 0 if there is an error between the calculated speed and the actual speed, the value in parentheses in equation (2) proportional to the calculated torque is 0 The calculation speed ω ₁₂ of the initial speed calculation means 9 is calculated so that

ここでωは二次磁束速度、ω_sはすべり速度、Ｒ_２は誘導機の二次抵抗である。 The speed calculation means 7 inputs the voltage command V * and the input current i, and outputs the calculation speed ω _m of the speed calculation means 7. In order to calculate the speed after the initial speed calculation, when the control switching signal CH is 0, the secondary magnetic flux Ψ _{2 is obtained} from the voltage command V * and the input current i of the induction machine 1 using the expressions (1) and (2). From the input current i of the induction machine 1 and the secondary magnetic flux Ψ ₂ , the calculation speed ω _m of the speed calculation means 7 is calculated using the equations (5) to (7).

Here, ω is the secondary magnetic flux velocity, ω _s is the slip velocity, and R ₂ is the secondary resistance of the induction machine.

Control switching means 10 receives the control switching signal CH and pre-excitation calculating unit 8 for computing speed omega ₁₁ and the initial speed calculating means 9 calculated speed omega ₁₂ and computing speed omega _m and the torque command of the speed calculation means 7 tau * The switching torque command τ ₀ * and the switching calculation speed ω ₁ are output. The switching torque command tau ₀ * and the switching operation speed omega ₁ for outputting to the control command generating section 6, the operation speed omega ₁₁ and the torque command 0 of pre-excitation operation means 8 when the control switching signal CH 1, the control switching signal When CH is 2, the calculation speed ω ₁₂ and torque command 0 of the initial speed calculation means 9 are switched to, and when the control switching signal CH is 0, the calculation speed ω _m and torque command τ * of the speed calculation means 7 are switched.

切替演算速度ω₁と切替トルク指令τ₀*と磁束指令φ*と電流指令I_q*から電流制御手段5と制御切替信号発生器12に出力する速度指令ω_m*を式(10)、式(11)で演算する。

ここでω_s*は滑り速度指令である。 The control command creating means 6 inputs the switching torque command τ ₀ *, the switching calculation speed ω ₁ and the magnetic flux command φ *, and outputs the current commands I _d *, I _q * and the speed command ω _m *. The current commands I _d * and I _q * to be output to the current control means 5 from the switching torque command τ ₀ * and the magnetic flux command φ * are calculated by the equations (8) and (9).

The speed command ω _m * output to the current control means 5 and the control switching signal generator 12 from the switching calculation speed ω ₁ , the switching torque command τ ₀ *, the magnetic flux command φ *, and the current command I _q * Calculate with (11).

Here, ω _s * is a slip speed command.

The current control means 5 inputs the input current i, the current commands I _d *, I _q *, and the speed command ω _m *, and outputs the voltage command V ₀ of the current control means 5. Based on the input current i of the induction machine 1, voltage switching means 11 and speed calculation means 7 such that the input current and speed of the induction machine 1 become current commands I _d *, I _q *, and speed command ω _m *, The voltage command V ₀ of the current control means 5 output to the initial speed calculation means 9 is calculated.

Voltage switching means 11 receives the voltage command V ₁ of the voltage command V ₀ and pre-excitation calculating unit 8 of the current control means 5, and outputs a voltage command V *. The voltage command V * to be output to the power converter, the voltage command of the control switching signal CH to the voltage command V ₁ of the pre-excitation operation means 8 when the 1, control switching signal CH is the current control means 5 when other than 1 Switch to V ₀ .

  With the above structure, when the induction machine 1 is started, the preliminary excitation calculation, the initial speed calculation, and the speed calculation are performed in this order, and smooth speed estimation can be performed. In addition, instead of the voltage command V * input to the speed calculation means 7, the preliminary excitation calculation means 8, and the initial speed calculation means 9, an equivalent speed estimation can be performed by using the input voltage v detected by the voltage detector 2. .

JP 11-285300 A

That is, according to the first aspect of the present invention, a control switching signal generator that inputs a speed command (ωm *) and outputs a control switching signal (CH) ;
Input current induction motor (i) and the voltage command (V *) to enter, voltage (V1) and computation speed (.OMEGA.11)
A pre-excitation operation means for outputting bets,
The inputs the voltage command and the input current (i) and (V *) and the voltage (V0), the initial velocity calculating means for outputting a computation speed (ω12),
The type and the specified voltage and the input current (i) (V *) and the voltage (V0), and speed calculating means for outputting a computation speed (.omega.m),
A torque command (tau *), before Ki演 enter calculated speed and (.OMEGA.11) and before Ki演 calculated speed (Omega12) pre Ki演 calculation speed (.omega.m), switching the torque command (.tau.0 *) and switching operation speed ( control switching means for outputting ω1),
The magnetic flux command (phi *) and type a Symbol SWITCHING torque command (.tau.0 *) and the switching operation speed (.omega.1), current command (Id *, Iq *) and the speed command (.omega.m *) and a control for outputting Command creation means;
Wherein said current command and the input current (i) (Id *, Iq *) and inputs the speed instruction (ωm *), and said current control means for outputting the voltage (V0),
Type a Symbol voltage (V0) and the voltage (V1), in the induction motor control device having a voltage switching means for switching the voltage command to be output to the power converter (V *),
The type and the specified voltage and the input current (i) (V *), and outputs the computation speed (ω13) to said control switch means, bisecting the computation secondary flux (Ψ23) to the initial velocity calculating means An initial speed calculation preparation means for outputting one value is added.

FIG. 4 shows an example of control when there is residual magnetic flux. 101 is a vector locus drawn by the secondary magnetic flux Ψ ₂ calculated by the preexcitation calculation means 7 using the equations (1) and (2), and 102 is an initial magnetic flux of the initial speed calculation means 9 calculated by the preexcitation calculation means 7. The secondary magnetic flux Ψ ₂₁ , 103 of the pre-excitation calculation means 8 is the vector locus of the secondary magnetic flux drawn by the secondary magnetic flux Ψ ₂ calculated by the equations (1) and (2) in the initial speed calculation means 9. is there.

予備励磁演算手段7で速度を推定後、初期速度演算手段9の初期値の予備励磁演算手段8の演算二次磁束Ψ₂₁を演算する時に残留磁束Ψ₂₀がある場合、式(12)により予備励磁演算手段8の演算二次磁束Ψ₂₁が残留磁束Ψ₂₀を含むことで、原点を中心にするベクトル軌跡を描く実際の磁束からずれた値になり、初期速度演算手段9が式(1)、式(2)を用いて演算する二次磁束Ψ₂は103の様に、中心点が原点からずれたベクトル軌跡を描き始める。 When there is a residual magnetic flux Ψ ₂₀ at the start, the expression (3) becomes the expression (12).

After estimating the speed in pre-excitation operation means 7, if there is a residual magnetic flux [psi ₂₀ when computing the arithmetic secondary flux [psi ₂₁ of pre-excitation operation means 8 of the initial value of the initial speed calculating means 9, the preliminary by the formula (12) Since the calculation secondary magnetic flux Ψ _{21 of the} excitation calculation means 8 includes the residual magnetic flux Ψ ₂₀ , it becomes a value deviated from the actual magnetic flux that draws a vector locus centering on the origin, and the initial speed calculation means 9 is expressed by the equation (1) The secondary magnetic flux Ψ ₂ calculated using the equation (2) starts to draw a vector locus with the center point deviated from the origin, as indicated by 103.

As a result, the initial speed calculation means 9 corrects the secondary magnetic flux Ψ ₂ deviated from the origin, so that it takes time to estimate the speed or if the magnetic flux deviation cannot be corrected, the speed cannot be estimated and cannot be started. The phenomenon that happens.
The present invention has been made to solve the above problems.

In order to solve the above-mentioned problems, the second control switching signal generator 14 that outputs the control switching signal CH instead of the control switching signal generator 12, and the calculation of the initial speed calculation preparation means 13 in the control switching means 10 The initial speed calculation preparation means 13 for outputting half the value of the calculated secondary magnetic flux Ψ ₂₃ of the initial speed calculation preparation means 13 after a certain time is added to the speed ω ₁₃ and the initial speed calculation means 9.

That is, a control switching signal generator that inputs a speed command (ω _m *) and outputs a control switching signal (CH), and an input current (i) and a voltage command (V *) Is input, the voltage (V ₁ ) of the preliminary excitation calculation means is output to the voltage switching means, the calculation speed (ω ₁₁ ) of the preliminary excitation calculation means is output to the control switching means, and the preliminary excitation is output to the initial speed calculation means The preliminary excitation calculation means for outputting the calculation secondary magnetic flux (Ψ ₂₁ ) of the calculation means, and the calculation secondary of the input current (i) and voltage command (V *) of the induction machine and the preliminary excitation calculation means by the control switching signal Initial speed calculation means for inputting magnetic flux (Ψ ₂₁ ) and outputting the calculation speed (ω ₁₂ ) of the initial speed calculation means to the control switching means, and the input current (i) and voltage of the induction machine by the control switching signal command (V *) to enter the fast outputs the operation speed of the speed calculating means (omega _m) to said control switch means Calculation means, in the control switching signal (CH), a torque command (tau *), the speed calculation operation speed and (omega ₁₂₎ calculated speed (omega ₁₁₎ and the initial speed calculation means of the pre-excitation operation means The control switching means for inputting the calculation speed (ω _m ) of the means and switching the switching torque command (τ ₀ *) and the switching calculation speed (ω ₁ ) output to the control command creation means, the magnetic flux command (φ *), A switching torque command (τ ₀ *) and a switching calculation speed (ω ₁ ) are input from the control switching means, and a current command (I _d *, I _q *) and a speed command (ω _m *) are output to the current control means. The control command generating means for outputting a speed command (ω _m *) to the control switching signal generator, the input current (i) of the induction machine and the current command (I _d *, I _q from the control command generating means *) and enter the speed command (omega _m *), the current system for outputting a voltage (V ₀₎ of the current control means to a voltage switching unit Switching means and the inputs of the control switching signals (CH) voltage of the current control means (V ₀₎ and the voltage of the pre-excitation operation means (V _1), the voltage command outputted to the power converter (V *) An induction machine control device having a voltage switching means includes a second control switching signal generator that inputs a speed command (ω _m *) and outputs a control switching signal (CH) instead of the control switching signal generator. In response to the control switching signal (CH), the input current (i) and voltage command (V *) of the induction machine are input, and the calculation speed (ω ₁₃ ) of the initial speed calculation preparation means is output to the control switching means. An initial speed calculation preparation means for outputting a half value of the calculation secondary magnetic flux (Ψ ₂₃ ) of the initial speed calculation preparation means is added to the speed calculation means.

Even if there is residual magnetic flux at the time of starting the induction machine, it is corrected so that the vector locus of the secondary magnetic flux Ψ ₂ rotates around the origin at the time of initial speed calculation, and smooth speed estimation can be performed.

FIG. 1 is a block diagram showing an embodiment of the present invention. FIG. 2 is a block diagram showing a conventional example. FIG. 3 is a vector diagram of magnetic flux drawn by one embodiment of the present invention. FIG. 4 is a vector diagram of magnetic flux drawn by one conventional example.

Instead of the initial speed calculation preparation means 13 and the control switching signal generator 12, a second control switching signal generator 14 is newly added, and even if there is a residual magnetic flux at startup, the secondary magnetic flux Ψ ₂ The vector trajectory is corrected to turn around the origin so that smooth speed estimation can be performed.

  FIG. 1 is a block diagram showing an embodiment of the present invention. 13 is an initial speed calculation preparation means, and 14 is a second control switching signal generator.

The second control switching signal generator 14 receives the speed command ω _m * and outputs the control switching signal CH. The control switching signal CH becomes 1 at the time of start, becomes 3 after a predetermined time when the speed command ω _m * is calculated by the preliminary excitation calculation means 8, and is calculated by the initial speed calculation preparation means 13 and is calculated by the initial speed calculation preparation means 13. _It becomes 2 after a certain period of time when the vector locus of ₂₃ circulates halfway, and becomes 0 after the speed command ω _m * follows the actual speed to such an extent that the magnetic flux can be calculated by the initial speed calculation means 12.

The initial speed calculation preparation means 13 receives the voltage command V * and the input current i, and outputs the calculation speed ω ₁₃ of the initial speed calculation preparation means 13 and the calculation secondary magnetic flux ψ ₂₃ of the initial speed calculation preparation means 13. In order to correct the vector trajectory of the secondary magnetic flux Ψ ₂ around the origin when calculating the initial speed, when the control switching signal CH is 3, the initial value of the secondary magnetic flux is set to 0, and the speed is calculated using the pre-excitation calculation. The initial speed calculation preparation means 13 is fixed using the calculated command speed ω ₁₁ of the preliminary excitation calculation means 8 and the voltage command V * and the input current i of the induction machine 1 using the expressions (1) and (2). the arithmetic secondary flux [psi _23, calculates a certain period of time the vector locus of the operational secondary flux [psi ₂₃ of the initial velocity calculating preparation means 13 is half, pre-excitation operation means as an initial velocity to the initial velocity calculating means 9 after a predetermined time the operation speed omega ₁₁ 8 and the operation speed omega ₁₃ of the same initial velocity calculating preparing means 13, and outputs a half value of the calculation secondary flux [psi ₂₃ of the initial velocity calculating preparation means 13 after a predetermined time as an initial flux.

Control switching means 10, the computing speed omega _m calculated speed omega ₁₃ and speed estimating unit 7 of the computing speed omega ₁₂ and the initial velocity calculating preparation means 13 for computing speed omega ₁₁ and the initial speed calculating means 9 of pre-excitation operation means 8 A torque command τ * is input, and a switching torque command τ ₀ * and a switching calculation speed ω ₁ are output. The switching torque command tau ₀ * and the switching operation speed omega ₁ for outputting to the control command generating section 6, the operation speed omega ₁₁ and the torque command 0 of pre-excitation operation means 8 when the control switching signal CH 1, the control switching signal When CH is 3, the control speed is switched to the calculation speed ω ₁₃ and torque command 0 of the initial speed calculation preparation means 13, and when the control switching signal CH is 2, the control speed is switched to the calculation speed ω ₁₂ and torque command 0 of the initial speed calculation means 9. When the signal CH is 0, the calculation speed ω _m of the speed calculation means 7 and the torque command τ * are switched.

FIG. 3 shows an example of control when the initial speed calculation preparation means 13 is added and there is a residual magnetic flux. 104 is a vector locus drawn by the calculation secondary magnetic flux Ψ ₂₃ of the initial speed calculation preparation means 13 calculated by the expressions (1) and (2), and 105 is an initial speed calculation means 9 calculated by the initial speed calculation preparation means 13. This is half the value of the calculated secondary magnetic flux Ψ ₂₃ of the initial speed calculation preparation means 13 after a certain time to become the initial magnetic flux. After the speed is estimated by the preliminary excitation calculation means 7, the initial speed calculation means 9 is rotated by the initial speed calculation preparation means 13, and the initial velocity calculation means 9 is made the initial value by halving the magnetic flux and setting the initial value of the initial speed calculation means 9. The initial magnetic flux of the initial speed calculation means 9 is corrected so that the center of the vector locus drawn by the secondary magnetic flux of the means 9 is the origin.

With the above structure, even if there is a residual magnetic flux at the time of starting the induction machine 1, it is calculated by the initial speed calculation means 9 by performing the initial speed calculation preparation means 13 before performing the initial speed calculation means 9. By correcting the center point of the vector locus of the secondary magnetic flux Ψ ₂ and rotating around the origin, smooth speed estimation can be performed. Further, instead of the voltage command V * input to the speed calculation means 7, the preliminary excitation calculation means 8, the initial speed calculation means 9 and the initial speed calculation preparation means 13, the input voltage v detected by the voltage detector 2 is used. Can estimate the same speed.

  Even if there is residual magnetic flux when starting the induction machine, smooth speed estimation can be performed.

DESCRIPTION OF SYMBOLS 1 Induction machine 2 Voltage detector 3 Current detector 4 Power converter 5 Current control means 6 Control command preparation means 7 Speed calculation means 8 Pre-excitation calculation means 9 Initial speed calculation means 10 Control switching means 11 Voltage switching means 12 Control switching signal Generator 13 Initial speed calculation preparation means 14 Second control switching signal generator 101 Secondary magnetic flux vector locus drawn by the preliminary excitation calculation means 7,
102 Calculated secondary magnetic flux Ψ ₂₁ after a predetermined time of the pre-excitation calculating means 7
103 Vector trajectory of the secondary magnetic flux drawn by the initial speed calculation means 9 104 Vector trajectory of the secondary magnetic flux drawn by the initial speed calculation preparation means 13 105 Half of the calculated secondary magnetic flux Ψ ₂₃ after a predetermined time of the initial speed calculation preparation means 13 value


v ··· Input voltage i ··· Input current ω ₁ ··· Switching calculation speed ω ₁₁ ··· Preliminary excitation calculation means calculation speed ω ₁₂ ··· Initial speed calculation means calculation speed ω ₁₃ .... the initial velocity calculating secondary flux [psi ₂₃ ... initial velocity calculation preparation of the operational speed [psi ₂₁ ... pre-excitation calculating means calculating the speed omega _m ... speed calculation means calculating preparation means Means of calculation secondary magnetic flux
V ₀・ ・ ・ ・ Voltage of current control means
V ₁・ ・ ・ ・ Voltage of pre-excitation calculation means
V * ・ ・ ・ ・ Voltage command φ * ・ ・ ・ ・ Flux command τ * ・ ・ ・ ・ Torque command τ ₀ * ・ ・ ・ ・ Switching torque command I _d * ・ ・ ・ ・ d-axis current command I _q * ・ ・・ ・ Q-axis current command ω _m * ・ ・ ・ ・ Speed command
CH ... Control switching signal

Claims (1)

A control switching signal generator that inputs a speed command (ωm *) and outputs a control switching signal (CH) ;
Input current induction motor (i) and the voltage command (V *) to enter, voltage (V1) and computation speed (.OMEGA.11)
A pre-excitation operation means for outputting bets,
The inputs the voltage command and the input current (i) and (V *) and the voltage (V0), the initial velocity calculating means for outputting a computation speed (ω12),
The type and the specified voltage and the input current (i) (V *) and the voltage (V0), and speed calculating means for outputting a computation speed (.omega.m),
A torque command (tau *), before Ki演 enter calculated speed and (.OMEGA.11) and before Ki演 calculated speed (Omega12) pre Ki演 calculation speed (.omega.m), switching the torque command (.tau.0 *) and switching operation speed ( control switching means for outputting ω1),
The magnetic flux command (phi *) and type a Symbol SWITCHING torque command (.tau.0 *) and the switching operation speed (.omega.1), current command (Id *, Iq *) and the speed command (.omega.m *) and a control for outputting Command creation means;
Wherein said current command and the input current (i) (Id *, Iq *) and inputs the speed instruction (ωm *), and said current control means for outputting the voltage (V0),
Type a Symbol voltage (V0) and the voltage (V1), in the induction motor control device having a voltage switching means for switching the voltage command to be output to the power converter (V *),
The type and the specified voltage and the input current (i) (V *), and outputs the computation speed (ω13) to said control switch means, bisecting the computation secondary flux (Ψ23) to the initial velocity calculating means An induction machine control device characterized by adding an initial speed calculation preparation means for outputting one value.

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