JPH09272663A - Drive controller for elevator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To hold high efficiency and suppress vertical vibration of a riding car, when load applied on an electric motor is changed in any state, by inputting deviation of an output of a load torque estimation means and a generated torque estimation means into a torque instruction. SOLUTION: A momentary torque generated inside an electric motor 60 is so controlled that the ratio of an excitation current and torque current following transitionally at high efficiency is held in relation to a torque instruction τR. At the same time, a vibration component of the electric motor loading torque is estimated and a vibration control signal τT<sup> is inputted into the torque instruction τR so as to miniaturize the vertical vibration of a riding car 90. The vibration of the riding car 90 is decreased, while controlling the electric motor 60 at high efficiency including its transitional state. This constitution can provide high energy saving effects and enlarge vibration control effects.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a control device for an AC electric motor, and more particularly to a control system suitable for a drive control device that suppresses vertical vibration of a car while maintaining high efficiency in a drive system of an elevator.

[0002]

2. Description of the Related Art In order to improve the efficiency of an elevator drive system, Japanese Patent Laid-Open No. 59-149283 discloses a slip angular frequency having a predetermined value when a deviation between an elevator speed command and an actual speed is within a predetermined range. It is disclosed to be fixed to.

Further, regarding an AC motor, in order to improve speed control performance with respect to load torque fluctuations, Japanese Patent Laid-Open No. 60-1251
Japanese Unexamined Patent Publication No. 87 discloses that a load torque of the electric motor is estimated from the electric motor speed detection value and the electric motor torque command value, and this is added to the torque command to reduce the torque pulsation.

[0004]

Generally, in an elevator, since the number of passengers in the car constantly changes, the load applied to the drive motor constantly changes. As a result, the torque to be generated in the electric motor changes according to the load, and at the same time, the torque must be generated such that the speed follows the speed command. In the first prior art described above, it was not possible to maintain high efficiency regardless of the load applied to the electric motor.

On the other hand, the second conventional technique does not consider the load of a mechanical system that constantly changes and tends to be oscillating like an elevator, and does not describe the improvement of efficiency at all.

An object of the present invention is to provide a drive control device for an elevator which can suppress vertical vibration of a car while maintaining high efficiency regardless of how the load applied to the electric motor changes, that is, transient state. It is to be.

[0007]

According to the present invention, there is provided a power converter that outputs a variable voltage variable frequency alternating current, an AC motor that is fed from the power converter and is driven at a variable speed, and is vertically driven by this motor. In the elevator having a vehicle, a means for generating a speed command for the elevator, and a speed control means for generating a torque command so that the speed of the AC motor follows the speed command, a motor current detection means,
Based on the output of this torque control means, means for estimating the generated torque or equivalent value of the induction motor from the detected current value, torque control means configured so that the torque command and the estimated torque value match. Means for controlling the electric power converter so that the torque current component and the exciting current component of the electric motor current have a predetermined relationship, and means for estimating the load torque or equivalent value of the electric motor from the electric motor speed, the load torque A deviation between the output of the estimating means and the output of the generated torque estimating means is injected into the torque command.

As the manipulated variable of the torque command, the exciting current / torque current ratio is determined according to the torque required at the present time, and the torque current command and the exciting current command are obtained.

In this case, the exciting current command with respect to the torque current command can be determined so as to have the minimum energy (input power of the electric motor) required to obtain the desired torque in the currently generated secondary magnetic flux. The combination of the exciting current component and the torque current component determined in this way is obtained corresponding to the changing speed command and torque command.

Therefore, no matter how the number of passengers in the car, that is, the load torque applied to the electric motor changes, the torque required to obtain the speed corresponding to the speed command is generated, preferably with the minimum energy. A combination of such an exciting current component and a torque current component is determined including a transient state, and a current corresponding to these two currents flows through the primary winding of the motor.

Further, the torque vibration component contained in the load torque applied to the electric motor is estimated from the deviation between the estimated load torque value obtained from the detected electric motor speed and the load and the estimated motor generated torque value. The estimated value of the torque vibration component is inverted in phase so as to cancel the vibration, and adjusted so as to reduce the magnitude of the vertical vibration of the car, and is preferably adjusted to the minimum value and injected into the torque command value.

[0012]

1 shows an embodiment of the present invention.

The AC of the AC power supply 10 is converted into DC by the converter 20, and this DC voltage is converted into the smoothing capacitor 3.
The smoothed direct current of 0 is further converted into a variable voltage and a variable frequency alternating current by the PWM inverter 40. This alternating current is supplied to an induction motor (IM) 60, which drives this motor 60 at a variable speed. The torque generated by the electric motor 60 is transmitted to the sheave (sheave) 70 via a gear (not shown) directly connected to the rotor (rotor) of the electric motor, and the counterweight (balance weight) is caused by the rotating operation of the sheave.
The rope that connects 80 and the car 90 is operated to drive the car 90 up and down.

Therefore, the weight difference between the counterweight and the car is applied as a load to the electric motor. Such loads continually fluctuate in elevators with varying crew, and for most operations are less than half the motor output. Therefore, if the driving efficiency of the electric motor can be increased during driving (transient state) and the load is light, power saving of the elevator drive system can be achieved.

In the elevator, the acceleration pattern (command) is determined by the acceleration pattern generating means 110 in consideration of riding comfort. The acceleration pattern generated by the means 110 is input to the speed command generating means 120. The means 120
Then, the acceleration pattern is integrated and converted into a speed command. The speed command ω _R is applied to the addition side terminal of the adder / subtractor 130,
Speed detector 1 attached to the rotor of the induction motor 60
Speed calculation means 1 based on the rotation pulse generated from 00
The rotational angular velocity ω _M of the rotor of the induction motor calculated in 21 is introduced to the terminal on the subtraction side of the adder-subtractor 130, and the deviation between the two is taken to generate a speed deviation. The speed deviation is input to the speed control means 140. The speed control means 140 generates a torque command τ _R for determining the torque to be generated in the induction motor 60 so that the speed deviation is eliminated.

The torque command τ _R is input to the plus terminal of the adder / subtractor 131, while the minus terminal of the adder / subtractor 131 is currently calculated by the generated torque estimating means 152 using equation (1). Instantaneous torque generated in

[0017]

[Outside 1]

Is input.

[0019]

[Equation 1]

[0020] However, m: number of phases, p: the number of poles of the induction motor, M: magnetizing inductance, l _2: leakage inductance, I _t: the detected torque current, phi _2: 2-order flux The secondary magnetic flux phi _2, based on the equation (2), the instantaneous magnetic flux contributing to the torque generation which is generated inside the induction machine at present estimated by calculating the secondary magnetic flux calculation means 151.

[0021]

[Equation 2] φ ₂ = (M · I _m ) / (1 + T ₂ · s) (2) where T _{2 is} a quadratic time constant, s is a Laplace operator (the same applies below), I _{m in} equation (2) Is an exciting current, which is an exciting current required to generate the secondary magnetic flux φ ₂ detected by the exciting current / torque current detecting means 150. Here, the excitation current I
_m, the torque current I _t, the current sensor 50, 51, 52
Primary current i _u of the three-phase detected by, i _v, based on i _w, it is determined by performing the calculation of Equation (3) above means 150.

[0022]

Equation 3] _{I m = (√2 / √3)} · {i u · cosθ 1 * + i v · cos (θ 1 * -2π / 3) + i w · cos (θ 1 * + 2π / 3)} I t = - (√2 / √3) · {i u · sinθ 1 * + i v · sin (θ 1 * -2π / 3) + i w · sin (θ 1 * + 2π / 3)} ... (3) However, θ ₁ * = ∫ω ₁ dt, ω ₁ is given by the sum of the rotational angular velocity ω _M and a slip angular frequency ω _s , which will be described later, at the inverter angular frequency, as shown in equation (4).

[0023]

Ω ₁ = ω _M + ω _s (4) The torque command τ _R obtained by the speed control means 140 and the generated torque obtained by the generated torque estimating means 152

[0024]

[Outside 2]

The deviation (torque deviation) between and is input to the torque control means 160. The torque control means 160 uses a torque command τ _R for making the torque deviation zero.
Determine the operation amount (compensation amount) τ * of. Usually, the means 16
0 consists of PI (proportional + integral) elements.

The manipulated variable τ * is the torque current command calculation means 1
70 is input. The means 170 calculates the torque current command I _t * by the equation (5).

[0027]

[Equation 5] I _t * = {τ * / φ ₂ } · {(M + l ₂ ) / M} · {1 / (m · p)} (5) Excitation current corresponding to the torque current command I _t * The command I _mR is determined by the torque current command calculation means 170 that determines the exciting current / torque current ratio by the method described below. The relationship between the two is determined so that the loss L in the induction motor is minimized.

[0028]

[Equation 6] L = A · I _m ² + B · I _t ² (6)

[0029]

Equation 7] _{A = (R s + R m} ), B = R s + R r · (M / L r) · (M / L r) ≒ R s + R r (7) L _r = M + l ₂ , R _s : primary resistance, R _m : iron loss resistance, R _r :
It is a secondary resistance.

The value of M / L _r is usually close to 1, that is,
Since the secondary leakage inductance l ₂ is much smaller than the excitation inductance M, the second term generally holds for B.

Assuming that the combination of the exciting current I _m and the torque current I _t required to generate a given torque τ is (I _t , I _m ), the torque τ is the product of I _t and I _m. Proportional to. Therefore, there are countless combinations of the above that satisfy Expression (8).

[0032]

[Equation 8] _{τ = k · I t · I} m (k: torque constant of proportionality) ... (8) Therefore, for generating a torque τ that has been When you are given there,
Ratio α _min (= I _m / I _t ) of the exciting current I _m and the torque current I _t at which the loss L in the electric motor given by the equation (6) is minimized.
Becomes equation (9).

[0033]

(9) (α _min ) ² = {R _s + R _r · (M / L _r ) ² } / (R _s + R _m ) ... (9) Therefore, the exciting current I _m and the torque that minimize the above loss. The ratio α _min to the current I _t is calculated as follows: the primary resistance R _s , the secondary resistance R _r ,
It becomes a function of the excitation inductance M and the iron loss resistance R _m . Here, the primary resistance R _s and the secondary resistance R _{r change} with the temperature inside the motor, the exciting inductance M changes with the exciting current I _m , and the iron loss resistance R _m changes with the speed (inverter angular frequency) of the electric motor. It is necessary to make it variable according to these fluctuations.

The embodiment shown in FIG. 1 shows an example in which the ratio α _min is corrected according to the speed of the electric motor 60. Fig. 2 shows the exciting current-torque current line obtained by the combination of the exciting current and the torque current that gives the maximum efficiency when the generated torque is changed, and the parameters given by equation (9) have already been calculated. It is given and there is no fluctuation. FIG. 4 shows an exciting current-torque current line when the speed changes, and the characteristic that gives the maximum efficiency changes with the speed. To compensate for this fluctuation, the correction coefficient K (ω _M ) is based on the rated speed ω _M10.
Should be calculated according to the speed.

[0035]

[Formula 10] α _min = K (ω _M ) · (ω _M / ω _M10 ) (10) Here, the correction coefficient K (ω _M ) is obtained by preparing a function table in which the velocity ω _M is a variable in advance. Keep it. This compensation mainly compensates the variation of the iron loss resistance R _m due to the speed. In practice, the parameter of the equation (9) varies depending on the temperature of the motor (temperatures on the primary and secondary sides), the motor speed, and the exciting current, and therefore it is necessary to obtain the parameter as shown in FIG.

[0036] Figure 4 is the motor temperature, excitation current, individual parameters of the equation (9) the speed of the motor as an input signal (information) give the best efficiency in the case of varied calculates the alpha _min, to the alpha _min FIG. 4 is a block diagram showing a method of obtaining a corresponding optimum combination of a torque current command and an exciting current command.

In the block 181, the primary resistance R _s and the secondary resistance R _r are obtained in advance as a function of the motor temperature (the temperature on the secondary side is usually difficult to detect, so the temperature converted to the primary side is used), and the table is obtained. The one that has been converted is prepared. When the motor temperature (flame temperature) (in the embodiment of FIG. 1 is omitted) is detected, R _s corresponding to the temperature, obtained from R _r the table.

A function table of the exciting inductance M corresponding to the exciting current is prepared in the block 182. When the detected exciting current is input, the exciting inductance M corresponding to the exciting current is obtained. Has become. In this way, it is necessary to compensate the exciting inductance because the exciting inductance M in the region where the exciting current is small.
Is almost constant, but when the exciting current increases, the magnetic flux saturates and the exciting inductance M sharply decreases.

In block 183, the second term of the numerator of the equation (9) is obtained from the compensated exciting inductance M and the secondary resistance R _r, and this is calculated with the primary resistance R _s obtained in block 181 and the block. using core-loss resistance R _m which is determined based on the motor speed detected from 184 calculates the alpha _min to give maximum efficiency, the alpha _min torque current command to I _t *
And the exciting current command I _mR is determined.

The torque current command I _t * obtained as described above
The current control is performed so that the torque current I _t and the exciting current command I _m corresponding to the combination of the exciting current command I _mR and the exciting current command I _mR flow inside the induction motor 60.

First, the exciting current control means 190 operates so that the exciting current I _m corresponding to the exciting current command I _mR flows. Here, the deviation between the excitation current command I _mR and the excitation current I _m detected by the excitation / torque current detection means 150 is taken by the adder / subtractor 132, and the excitation current control means 190 makes the deviation zero. To generate a new manipulated variable I _m * of the exciting current. The exciting current control means 190
Is set to operate faster than the torque control means 160. This is because by increasing the response of the exciting current, the secondary magnetic flux corresponding to the required torque is determined early and the torque is stabilized.

The three-phase AC current command i is calculated by the current command calculation means 200 based on the equation (11) according to the torque current command I _t * and the operation amount I _m * of the exciting current command obtained in the above process.
_u *, i _v *, to generate a i _w *.

[0043]

I i_u* = I₁・ Cos (θ₁+ Δ) i_v* = I₁・ Cos (θ₁+ Δ-2π / 3) (11) i_w* = I₁・ Cos (θ₁+ Δ + 2π / 3) where θ₁= ∫ω₁dt, ω₁= Ω_M+ Ω_s ω_s= (MI_m*) / (T_Two・ Φ_Two), T_Two= (M + 1_Two)
/ R_Two  δ = tan-1 (I_t* / I_m*), (I₁)^Two= (I_t*)^Two＋ (I_m
*)^Two The above AC current command i_u*, I_v*, I_w* Indicates current detection
Three-phase AC current i detected from the generators 50, 51, 52
_u, I_v, I_wThe current control means 220 so that
Phase modulated wave V_u*, V_v*, V_w* (Omitted in the diagram of Figure 1) Occurrence
I do. The modulated wave is input to the PWM signal generating means 230.
And compared with carrier wave (triangular wave, not shown) PWM signal
And the PWM signal configures the PWM inverter 40.
Applied to the gate of the power device to be formed.

As a result, a terminal voltage that causes a torque corresponding to the torque command is generated at the terminal of the PWM inverter 40, and a combination of the torque current and the exciting current that always gives the highest efficiency flows inside the motor. Like Since this relationship is maintained regardless of the state of the load, the electric motor is always driven with the highest efficiency including the transient state. Therefore, in an elevator drive system where the number of passengers in the car constantly fluctuates and the load torque applied to the electric motor fluctuates, the average (statistical) load applied to the electric motor during operation is generally the rated value of the electric motor. Since it is often driven in a light load state of less than half the torque, the energy saving effect is particularly great.

Generally, an elevator has a natural vibration frequency in a region where it easily resonates with a driving frequency of an electric motor, which is excited by torque ripple of the electric motor and deteriorates the riding comfort of the elevator. The vibration has a mode superimposed on the motor speed. Therefore, if the load torque vibration can be estimated using the detected motor speed and the phase of the estimated value can be inverted and injected into the torque command, the vibration can be suppressed and a good ride comfort can be secured.

FIG. 5 shows an example of a block diagram for generating the vibration suppression signal. A method of generating the vibration suppression signal will be described with reference to FIG.

First, the following relationship is established between the torque τ _M generated by the electric motor, the disturbance torque τ _d appearing on the shaft of the electric motor, and the load torque τ applied to the electric motor.

[0048]

(12) τ _M + τ _d = τ (12) In addition, the total moment of inertia of the mechanical system around the axis of the electric motor is J
After all,

[0049]

(13) τ / (J · s) = ω _M (13) holds. Normally, J is known at the mechanical system design stage, so the estimated value of τ by the load torque estimating means 300.

[0050]

[Outside 3]

Can be obtained.

[0052]

[Equation 14]

On the other hand, τ _M is the estimated value of the generated torque by the generated torque estimating means 152.

[0054]

[Outside 4]

Is calculated as Therefore, τ _d is
Estimated value from 2) and equation (14)

[0056]

[Outside 5]

Can be calculated as in equation (15).

[0058]

(Equation 15)

Thus obtained

[0060]

[Outside 6]

The noise suppressing component is removed by the low-pass filter of the signal adjusting means 301, the gain and phase are adjusted so as to reduce the vertical vibration of the car, and the vibration suppressing signal τ is obtained.
_sup is output. Then, by injecting this τ _sup into the torque command, a torque command capable of suppressing vibration is generated.

FIG. 6 shows how the car vertically vibrates before and after the vibration suppression signal is injected when a steady load torque vibration occurs in a certain state.

By the way, generally, the acceleration pattern (command) of the elevator is usually determined so as to obtain an optimum riding comfort, and this is integrated to generate a speed command. In the present embodiment, the instantaneous torque of the electric motor is generated so that the speed of the electric motor follows the speed command regardless of the load state. There is also an effect that vibration due to an impact disturbance such as a shock due to an incorrect start compensation can be quickly suppressed.

In this embodiment, the torque control means 16 for negatively feeding back the output of the generated torque estimating means 152.
Although 0 is provided, the torque control means is not always necessary, and the output of the speed control means 140 may be directly input to the torque current command calculation means 170. In addition, although the signal adjusting means 301 is provided with a low-pass filter, ω _M is used in the speed calculating means and ω _M is used in the generated torque estimating means 152.

[0065]

[Outside 7]

It may be omitted if the noise component of is removed, and a band pass filter may be used when a steady error appears in the vibration suppression signal. Further, when there is a phase difference between the estimated load torque and the estimated generated torque, the output of the load torque estimating means 300 can be attached with a phase adjuster to eliminate the phase difference.

FIG. 7 shows another embodiment. Only parts different from the embodiment shown in FIG. 1 will be described.

The difference from the embodiment shown in FIG. 1 is that a load detector 400 for detecting the load in the car and a load variation calculation means 401 for obtaining the load variation ΔJ of the inertia moment J from its output are provided. The torque estimating means 300 is
The point that can be adjusted according to J and the torque command τ *
And an initial inertial value computing means 402 for obtaining J from the motor rotation angular velocity ω _M, etc., and a data holding means 40 capable of holding the J and updating the J used in the load torque estimating means 300.
3 is provided.

In the elevator, J always fluctuates depending on the number of passengers in the car. Therefore, the load fluctuation ΔJ is obtained by the load fluctuation calculation means 401, and the value of J used for load torque estimation is calculated every time the number of passengers fluctuates. The load torque can be estimated more accurately by increasing or decreasing Δ according to ΔJ.

Further, the initial inertial value computing means 402 calculates from the rotational angular velocity ω _M1 reached by the electric motor when a constant torque command value τ ₁ * is given for a constant period t ₁ , for example,

[0071]

Since ω _M1 = τ ₁ * · t ₁ / J (16) holds, J can be calculated. In this way, J is calculated regularly or irregularly immediately after installation of the elevator or after operation, and J used in the load torque estimating means 300 is automatically updated, thereby eliminating the deviation of J from the design value due to secular change or the like. be able to.

As a result, accurate load torque estimation can always be performed, so that not only the start compensation error and the increase in car vibration due to aging etc. can be suppressed, but also the start compensation adjustment and maintenance inspection immediately after installation of the elevator. It also has the effect of reducing adjustment items and the like. In the present embodiment, a means for adjusting the two Js of the load variation calculation means 401 and the initial inertia value calculation means 402 is provided, but at least either one can perform accurate load torque estimation, so at least Vibration suppression effect can be exhibited.

FIG. 8 shows another embodiment. Only parts different from the embodiment of FIG. 1 will be described.

First, the difference from the embodiment of FIG. 1 is that the excitation current command I _mR is obtained in FIG. 1 in correspondence with the torque current command I _t * obtained from the torque current command calculation means 170. In the present embodiment, the secondary magnetic flux command φ ₂ * is obtained by once converting the exciting current command I _m * by the following equation, and the secondary magnetic flux command φ ₂ * is generated by the secondary generated inside the electric motor 60. That is, it is configured to follow the magnetic flux φ ₂ .

[0075]

[ _Expression 17] φ ₂ * = (I _mR · M) / (1 + T ₂ · s) (17) Note that the combination of the torque current command I _t * and the exciting current command I _mR is the same as in the embodiment shown in FIG. Use the equivalent of the one described. The secondary magnetic flux command φ ₂ * and the secondary magnetic flux calculating means 1
The secondary magnetic flux φ ₂ calculated from equation (2) by 51 is introduced into the adder / subtractor 132 to generate the magnetic flux deviation Δφ ₂ . The secondary magnetic flux control means 186 determines the manipulated variable I _m * of the exciting current so that the magnetic flux deviation Δφ ₂ converges to zero. Then, using the torque current command I _t * and the operation amount of the excitation current I _m *, the three-phase current command _{i u *, i v *,} i w * was generated by the current command calculation unit 200, said current A modulated wave is generated by the modulated wave generation means 220 so that the primary current flowing through the primary winding of the motor follows the command, and P is generated based on the modulated wave.
Generate a WM signal. These series of operations have already been described in the embodiment of FIG.

The present embodiment is a method of controlling the torque current and the secondary magnetic flux so that the maximum efficiency is obtained. As a result,
The efficiency can be maintained at the maximum, and the torque control accuracy can be further improved.

FIG. 9 shows an AC current control means 210 for causing the electric current to flow inside the electric motor 70 by a combination of the torque current command and the exciting current command that give the maximum efficiency obtained in the above-described embodiments. It is configured to directly generate a modulated wave without providing it. Only the structural difference from the above-described embodiment will be described.

Torque current command I _tR (up to the above embodiment,
Since it is the same until the torque current command calculation means 170 is obtained (described as I _t *), it will be omitted.

A torque current deviation between the torque current command I _tR and the torque current I _t detected by the excitation / torque current detecting means 150 is generated from the adder / subtractor 133 and the q-axis voltage is determined based on the torque current deviation. The q-axis voltage V _q ′ is obtained by the means 171 and the exciting current command I _mR (where I _mR is I
Based on _tR from the exciting current / torque current ratio determining means 180 that determined by the aforementioned method) and the excitation component / torque current of the excitation current I _m obtained from the detecting means 150 excitation current deviation subtracter 132 Generated from the d-axis voltage determining means 17
The difference is that the d-axis voltage V _d ′ is obtained depending on the number 2.

If the above voltages V _q ′ and V _d ′ are used as they are, they will interfere with each other between the d axis and the q axis.

Therefore, the mutual interference between the d-axis and the q-axis is corrected and suppressed by the decoupling means 201 on the basis of the equation (18) to correct the voltages V _q ′ and V _d ′.

[0082]

V _d * = r ₁ · I _m * −ω ₁ · σ · L _s · I _t * + V _d ′ V _q * = r ₁ · It * + ω ₁ {σ · L _s · I _m * + _{(M / L r) · φ} 2} + V q 'σ = 1- (M / L s) · (M / L r), Ls = M + l 1, L r = M + l 2 (18) The two phases of the d-axis voltage V _d * and the q-axis voltage V _q * are converted into three-phase voltage commands V _u *, V _v *, V _w * by the two-phase / three-phase conversion means 202 (excitation). (Corresponding to the inverse conversion of the three-phase / two-phase conversion of the minute / torque component current detecting means 150), and the voltage command of the three-phase is used as a modulation wave to generate
The PWM signal is generated by the WM signal generating means 230, and the PW is generated.
The PWM inverter 40 is controlled by the M signal to drive the induction motor 60.

In the above-mentioned embodiment, the alternating current control system is adopted and it is necessary to perform high-speed calculation. On the other hand, in the present embodiment, since only the voltage control system is used to process the amount of direct current, there is no need to perform high-speed calculation, and since the response gain can be increased, stable driving can be performed up to the high-speed region, and high-efficiency driving over a wide range. While suppressing the vibration.

[0084]

According to the present invention, in response to the torque command,
The instantaneous torque generated inside the motor is controlled so that the ratio of the excitation current and the torque current that can transiently follow with high efficiency can be maintained, and at the same time, the vibration component of the motor load torque is estimated. Since the vibration suppression signal is injected into the torque command so as to reduce the vertical vibration of the car, the vibration of the car can be reduced while controlling the electric motor with high efficiency even in the transient state. As a result, the number of people in the car always fluctuates like an elevator, has a vibrating mechanical system, and the load torque applied to the electric motor fluctuates,
Especially for a drive system that includes a vibration component due to torque pulsation or mechanical resonance of an electric motor, the energy saving effect is particularly great, and the vibration suppressing effect is also great.

[Brief description of drawings]

FIG. 1 is a block diagram of one embodiment of the present invention.

FIG. 2 is a diagram illustrating a relationship between a torque component current and an excitation component current (or magnetic flux) that give the maximum efficiency in a certain state.

FIG. 3 is a diagram illustrating a relationship between a torque component current and an excitation component current (or magnetic flux) that give the maximum efficiency when the speed of the electric motor is variable.

FIG. 4 is an example of a block diagram for obtaining a ratio between an excitation current component and a torque current component, which gives the maximum efficiency when various parameters of the electric motor fluctuate.

FIG. 5 is an example of a block diagram for obtaining a vibration suppression signal.

FIG. 6 is a diagram for explaining how the car vertically vibrates before and after the vibration suppression signal is injected when steady load torque vibration occurs in a certain state.

FIG. 7 is a block line of another embodiment of the present invention in which the load torque estimation is made more accurate in consideration of the load variation in the configuration of FIG. 1 and the mechanical system inertia moment initial value can be obtained and adjusted. It is a figure.

FIG. 8 is a block diagram of another embodiment of the present invention in which the pattern that gives the highest efficiency is obtained from the secondary magnetic flux command and the torque current command in the configuration of FIG. 1 to perform torque control.

9 is a diagram showing another embodiment of the present invention in which a PWM control modulated wave is obtained from the current control system of FIG. 1 to directly configure a dq axis voltage control system for torque control. It is a block diagram.

[Explanation of symbols]

10 ... AC power supply, 20 ... Converter, 30 ... Smoothing capacitor, 40 ... PWM inverter, 60 ... Induction motor, 8
0 ... counter weight, 90 ... car, 110 ... acceleration pattern generating means, 120 ... speed command generating means, 140
... Speed control means, 152 ... Generated torque estimation means, 160
... torque control means, 170 ... torque current command calculation means,
180 ... Exciting current / torque current ratio determining means, 190 ... Exciting current control means, 200 ... Current command computing means, 210 ...
Current control means 300 ... Load torque estimation means 400 ...
Load detector, 401 ... Load variation calculation means.

Claims (10)

[Claims] 1. A power converter that outputs a variable voltage variable frequency alternating current, an AC motor that is fed from the power converter and is driven at a variable speed, a car that is driven up and down by this motor, and a speed command for an elevator. And a speed control means for generating a torque command so that the speed of the AC motor follows the speed command, a motor current detection means, and a generation of the induction motor from the current detection value. A means for estimating a torque or an equivalent value, a torque control means configured so that the torque command and the estimated torque value match, and a torque current component of the electric motor current and an exciting current based on the output of the torque control means. Means for controlling the electric power converter so that the components have a predetermined relationship, and means for estimating the load torque of the electric motor or the equivalent value from the electric motor speed. For example, the drive control device for an elevator, which comprises injecting a deviation of the output of the output and the generated torque estimating means of the load torque estimating means to said torque command. 2. A converter for converting AC to DC, a PWM inverter for converting an output voltage of the converter into AC of variable voltage / variable frequency, and a capacitor connected to a DC circuit between the converter and the inverter. , An induction motor fed from this PWM inverter, means for generating a speed command for an elevator, a car driven up and down by the induction motor, and a torque so that the rotational angular speed of the induction motor follows the speed command. In an elevator having speed control means for generating a command, a means for detecting the current of the induction motor, a means for estimating a generated torque of the motor or a corresponding value from the detected value of the motor current, the torque command and the estimated value. And the electric motor current based on the output of the torque control means. A means for controlling the electric power converter so that the torque current component and the exciting current component have a predetermined relationship, a means for estimating the load torque of the electric motor or a corresponding value from the angular velocity of the electric motor, and an output of the load torque estimating means. An elevator drive control device comprising signal adjusting means for inputting a deviation between the output of the generated torque estimating means and the output of the generated torque estimating means. 3. The drive control device for an elevator according to claim 1, wherein the load torque estimating means is adjusted according to the load variation of the elevator. 4. The drive control device for an elevator according to claim 1, wherein the load torque estimating means uses a moment of inertia of the elevator and has means for calculating a magnitude of the moment of inertia. 5. The elevator drive control device according to claim 1, wherein the predetermined relationship is a ratio of a torque current and an exciting current determined according to the magnitude of the torque command. 6. The ratio according to claim 5, wherein the ratio of the torque current to the exciting current determined according to the magnitude of the torque command is determined in relation to the speed of the electric motor or the frequency of the inverter. Elevator drive control device. 7. The drive control device for an elevator according to claim 5, wherein the ratio of the torque current and the exciting current determined according to the magnitude of the torque command is determined in relation to the temperature of the electric motor. . 8. The electric power input to a motor according to claim 1 or 2, wherein the predetermined relationship is a relationship between a torque current value and an exciting current value required to generate a torque according to the torque command in the electric motor. A drive control device for an elevator, wherein the torque current value and the exciting current value are in a region where the value is small. 9. The motor according to claim 1 or 2, wherein the motor generates a secondary magnetic flux corresponding to a secondary magnetic flux command determined based on a ratio between the secondary magnetic flux of the electric motor and the torque current, which is determined from the torque command. An elevator drive control device including an exciting current control unit that operates so as to follow such an exciting current command. 10. An elevator drive control apparatus according to claim 1, further comprising means for generating an acceleration command and means for integrating the acceleration command to calculate the speed command.