WO2018003500A1

WO2018003500A1 - Elevator control device

Info

Publication number: WO2018003500A1
Application number: PCT/JP2017/021938
Authority: WO
Inventors: 英二横山; 大塚　康司
Original assignee: 三菱電機株式会社
Priority date: 2016-06-30
Filing date: 2017-06-14
Publication date: 2018-01-04
Also published as: CN109328175B; CN109328175A; DE112017003268T5; KR102084917B1; JP6556353B2; KR20190013873A; DE112017003268B4; JPWO2018003500A1

Abstract

Provided is an elevator control device with which unbalance torque after brake release can be estimated in a short amount of time and corrected, whereby startup shock and car rollback can be stabilized and reduced. The present invention is provided with: a switching unit for estimating unbalance torque, which is the weight difference between a car and a balancing weight, using an unbalance torque estimator on the basis of motor drive current or a motor torque current command signal, and a motor speed detection signal, the switching unit selecting whether to output, as a torque offset current command signal, a signal obtained by adding the estimated unbalance torque and a value proportional to the speed signal, or to output, as the torque offset current command signal, the estimated unbalance torque after the brake for braking the rotation of the motor is released; and an addition unit for adding, to a torque current command signal which is the input of a current control unit, the torque offset current command signal output from the switching unit.

Description

Elevator control device

The present invention relates to an elevator control device, and more particularly to an elevator control device that reduces a start-up shock that occurs when the elevator starts running.

Generally, in a rope type elevator, a car and a counterweight are suspended by a rope through a sheave connected to a motor. When the car is stationary, the car is held stationary by the brake, but at the start of traveling, the brake is released and the sheave is rotated by the motor to move up and down.

At this time, as the brake is released, the unbalance torque of the weight difference between the car and the counterweight is transmitted to the motor through the sheave. From the viewpoint of motor speed control, the unbalance torque acts as a stepped disturbance. Therefore, if the brake is released while the motor torque is zero, the motor (sheave) is affected by the stepped disturbance and Acceleration fluctuations (hereinafter referred to as starting shocks) and car rollback occur. Since both of them deteriorate the ride comfort, measures are required.

Therefore, in order to reduce the start shock and the rollback of the car, the load weight of the car is detected, the unbalance torque is estimated, and the torque (torque offset current) that cancels the unbalance torque is generated by the motor. Generally, a start control method for releasing the brake is performed.

This method requires a load detection device for detecting the load weight of the car, which increases costs. Furthermore, installation and adjustment of the load detection device are required at the time of installation.
For this reason, the control system which reduces a starting shock and a rollback is proposed, without using a load detection apparatus (for example, refer patent document 1).
In this patent document 1, the unbalanced torque at the time of start-up is obtained by calculating the second-order differential operation of the angle information of the motor encoder to obtain the angular acceleration information. The sum of moment of inertia) information is used to calculate a torque bias command value and add it to the torque command value to control the lifting machine drive motor.

JP 2005-132541 A

In conventional elevator control devices, since the encoder information of the motor is quantized, there is a problem that the value of the discretization timing is greatly mistaken when the differential calculation is performed in an environment discretized by a calculation means such as a microcomputer.

Therefore, in Patent Document 1, the differential calculation is not performed every motor encoder cycle, but is performed in units of a predetermined number of encoder pulses.
Therefore, in principle, when the rollback amount is several millimeters to 10 millimeters and the unbalance torque is large, there is a problem that the start shock and the rollback of the car are not sufficiently reduced.

The present invention has been made in order to solve the above-mentioned problems, and it is possible to stably reduce the start shock and the rollback of the car by estimating and correcting the unbalance torque after the brake is released in a short time. It is an object to provide an elevator control device.

In order to achieve the above object, an elevator control apparatus according to the present invention includes a current detection unit that detects a drive current of a motor that rotationally drives a sheave in which a car and a counterweight are suspended by a rope, and the motor. A speed calculation unit that outputs a speed signal of the motor from an output of a rotation amount detection unit that detects a rotation amount of the motor, a speed command generation unit that generates a speed command signal for the motor, the speed command signal, and the speed signal A speed control unit that outputs a torque current command signal; a current control unit that drives the motor so that the drive current follows the torque current command signal; and an amplifier that is a weight difference between the car and the counterweight. An unbalance torque estimator for estimating a balance torque based on the drive current or the torque current command signal and the speed signal; and a torque offset As the flow command signal, a signal obtained by adding the output signal of the unbalance torque estimator and a value proportional to the speed signal is output, or the unbalance torque is released after the brake that brakes the rotation of the motor is released. A switching unit that selects whether to output an output signal of the estimator; and an addition unit that adds the torque offset current command signal output from the switching unit to the torque current command signal that is an input of the current control unit; I have.

According to the present invention, the unbalance torque, which is the weight difference between the car and the counterweight, is estimated by the unbalance torque estimator based on the motor drive current or the motor torque current command signal and the motor speed detection signal, A signal obtained by adding the estimated unbalance torque and a value proportional to the speed signal is output as a torque offset current command signal, or after the brake that brakes the rotation of the motor is released, the estimated unbalance torque is Since it is configured to include a switching unit that selects whether to output as a torque offset current command signal, and an addition unit that adds the torque offset current command signal output from the switching unit to the torque current command signal that is input to the current control unit Even if there is unbalance torque when the brake is released, the unbalance torque can be accurately measured in a short time. Since the car vibration with activating the elevator estimated stable state by correcting quickly the suppressing convergence, there is an effect that it is possible to stably reduce the rollback.

It is a block diagram which shows the control apparatus of the elevator by Embodiment 1 of this invention. It is the equivalent circuit diagram which modeled the disturbance observer shown in FIG. It is a block diagram which shows the structure of the passage / holding switching part shown in FIG. FIG. 3 is a complex plan view showing the movement of the pole arrangement of the disturbance observer shown in FIGS. 1 and 2. In the elevator control apparatus according to Embodiment 1 of the present invention, the effect of feedback control using a disturbance estimation signal as a torque offset current signal is a waveform diagram shown in (b) of the figure, where (a) in the figure is the above It is a wave form diagram when there is no feedback control. In the elevator control apparatus according to Embodiment 1 of the present invention, the effect of the speed feedback control is a waveform diagram shown in (b) of the figure, where (a) is the waveform when there is no speed feedback control. FIG. In the elevator control apparatus according to Embodiment 1 of the present invention, the effect of the change in the pole placement of the disturbance observer is a waveform shown in (b) in the figure, and (a) in the figure shows the case where there is no change in the pole arrangement. It is a waveform diagram. It is a concrete time-axis waveform diagram of the pole arrangement change of the disturbance observer shown in FIG.1 and FIG.2. FIG. 2B is a waveform diagram showing the effect of holding the waveform of the torque offset current signal shown in FIG. 1, and FIG. 4A is a waveform diagram when there is no waveform holding. FIG. 10 is an enlarged view of the time axis of FIG. 9, and is a waveform diagram illustrating waveform holding timing. It is a block diagram which shows the control apparatus of the elevator by Embodiment 2 of this invention. FIG. 12 is an equivalent circuit diagram obtained by modeling the disturbance observer illustrated in FIG. 11. It is a time-axis waveform diagram which shows the difference in the behavior by the timing which stops the speed feedback control by Embodiment 3 of this invention. It is a block diagram which shows the structure of the passage / holding switching part by Embodiment 3 of this invention. It is a figure which shows the timing of the magnification change of the speed feedback gain by Embodiment 3 of this invention. It is the equivalent circuit diagram which modeled the disturbance observer by Embodiment 4 of this invention. FIG. 17 is a specific time axis waveform diagram for changing the cutoff frequency of the band limiting filter of FIG. 16.

Hereinafter, embodiments of an elevator apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

Embodiment 1 FIG.
In the elevator control apparatus according to Embodiment 1 shown in FIG. 1, a sheave 2 is connected to the rotating shaft of the motor 1. A rope 3 is hung on the sheave 2, a car 4 is suspended at one end, and a counterweight 5 is suspended through the rope 3 at the other end. The motor 1 is provided with a pulse encoder 11 for detecting an angle, and speed control described below is executed based on the angle information. A motor angle detection signal that is an output of the pulse encoder 11 is input to the speed calculation unit 12.

The speed calculation unit 12 has a function of converting a motor angle detection signal into an angular speed signal of the motor 1 and outputs a speed signal ω. A process of subtracting the speed signal ω from the speed command signal ω_ref which is the output of the speed command generator 13 is performed by the subtractor 14 to obtain a speed error signal ω_err. This speed error signal ω_err is input to the speed control unit 15 and is a speed control that is a result of proportional (P), integral (I), and differential (D) operations so that the speed control is stable and a predetermined performance is obtained. The signal iq_ω_cont is output.

The adding unit 16 generates a torque current command signal iq_t * obtained by adding a speed control signal iq_ω_cont and a torque offset current signal iq_t * _off described later. The torque current command signal iq_t * is input to the current control unit 9. The current control unit 9 controls the motor drive current signal iq from the current detection unit 10 to be the torque current command signal iq_t * input from the addition unit 16. Therefore, the current control unit 9 supplies the motor drive current iq so as to become the torque current command signal iq_t * to the motor 1.
With the above configuration, a speed control system is realized in which the speed ω of the motor 1 functions so that the speed error signal ω_err follows the speed command signal ω_ref within a predetermined value.

The brake 6 has a state of braking and brake release (hereinafter referred to as release) with respect to the motor 1, and changes state via the brake control unit 8 in response to a brake control command signal BK_cont from the controller 7. When the car 4 is moved from the current floor to the predetermined floor, the brake 6 is changed from the braking state to the released state, and the speed control system is changed from the OFF state to the ON state at the brake release timing. The speed command signal ω_ref at the time of the ON state is set to zero.

When the torque difference from both ends of the rope 3 hung on the sheave 2 is zero, the torque from the rope 3 applied to the sheave 2 when the brake 6 is released is balanced, so there is no starting shock and no rollback. .

When there is a torque difference from both ends of the rope 3 hung on the sheave 2 (hereinafter referred to as unbalance torque), the torque applied from the rope 3 applied to the sheave 2 when the brake 6 is released is not balanced. This is equivalent to a so-called stepped disturbance acting on the control system, and rollback and startup shocks, and in some cases, car vibrations, occur until the tracking operation of the speed control system is settled.

As a countermeasure, a disturbance observer 17 for estimating the unbalance torque and a pass / hold switching unit 18 are provided, and a function for generating a torque that cancels the unbalance torque based on the unbalance torque estimated by the disturbance observer 17. Torque offset current signal iq_t * _off is generated.

The generation of the torque offset current signal iq_t * _off is performed as follows.
First, a method for estimating the unbalance torque will be described.
The unbalance torque is estimated by the disturbance observer 17. The disturbance observer 17 receives the motor drive current iq and the speed signal ω, and outputs a disturbance estimation signal Di ^. In addition, this is a configuration in which the pole arrangement which is a parameter for determining the estimated frequency characteristic (disturbance estimation band) of the disturbance observer 17 is changed by the brake control command signal BK_cont.

FIG. 2 shows an equivalent circuit in which the disturbance observer 17 is modeled, and the disturbance observer 17 corresponds to a portion surrounded by a dotted line. Blocks 200 to 203 are models in which the current control unit 9, the motor 1 and the sheave 2 of FIG. 1 are modeled and displayed as a transfer function, and the coefficient Kτ of the block 200 indicates a force constant for converting the motor drive current iq into torque. Di is an unbalance torque transmitted from the rope 3 hung on the sheave 2, and is applied to the motor 1 as a step-like disturbance by releasing the brake 6.

In this block diagram, block 201 represents the addition of unbalance torque Di. 1 / J of the block 202 indicates the amount of torque converted into angular acceleration, and J is defined as the sum of the moment of inertia of the motor 1 and the sheave 2. Block 203 is an integrator that converts angular acceleration into angular velocity. The block 204 models the pulse encoder 11 and the speed calculation unit 12 shown in FIG. 1, and models the encoder resolution characteristics of the pulse encoder 11 and the calculation characteristics for calculating the angular velocity ω from the speed calculation unit 12. .

The disturbance observer 17 is a disturbance observer of the minimum dimension type, has the above-described blocks 200 to 203 as an internal model, and is configured to be able to be estimated by defining the unbalance torque Di as a state. The configuration of the disturbance observer 17 may be the same dimensional format. The block 171 is modeled as a coefficient Kτn corresponding to the coefficient Kτ of the block 200, the block 172 is an addition block, and the block 173 is a coefficient Jn that models the sum J of the moments of inertia of the motor 1 and the sheave 2 and disturbance. A block which gives a coefficient having the eigenvalue λ (t) of the observer as a parameter, a block 174 is a first-order low-pass filter using the eigenvalue λ (t) as a parameter, and a block 175 is an addition block. The eigenvalue λ (t) is defined as a time-dependent function and corresponds to the above-described pole arrangement.

In the internal configuration of the pass / hold switching unit 18 shown in FIG. 3, the disturbance estimation signal Di ^ is input to the sample hold unit 182 after being multiplied by the inverse of the coefficient Kτn in the coefficient block 181 and input to the block 185. Is done. The speed signal ω is multiplied by α in the coefficient block 184, input to the block 185, and the result added to the output of the coefficient block 181 is given as one input signal of the switch unit 183.

The signal holding control of the sample hold unit 182 and the switch switching control of the switch unit 183 are performed based on a signal obtained by delaying the brake control command signal BK_cont by a predetermined time (T1) by the delay unit 186. The output of the switch unit 183 is output as the torque offset current signal iq_t * _off to the adding unit 16 shown in FIG.

With the configuration as described above, the torque offset current signal iq_t * _off is set to the signal A obtained by adding the signal obtained by multiplying the disturbance estimation signal Di ^ by 1 / Kτn and the signal obtained by multiplying the speed signal ω by α in the block 185, Alternatively, the signal obtained by multiplying the disturbance estimation signal Di ^ by 1 / Kτn to the signal B sampled and held by the sample hold unit 182 at a timing delayed by a predetermined time (T1) by the delay unit 186 from the brake release timing by the brake control command signal BK_cont. A switching function for selecting whether to perform the switching by the switch unit 183 is realized.

The selection by the switch unit 183 is performed by a signal obtained by delaying the brake release signal by the brake control command signal BK_cont by the delay unit 186 by a predetermined time (T1). Accordingly, the passage / hold switching unit 18 passes the signal A obtained by adding the signal obtained by multiplying the disturbance estimation signal Di ^ by 1 / Kτn and the signal obtained by multiplying the speed signal ω by α for a predetermined time (T1) from the release of the brake. Alternatively, whether the signal B sampled and held at a timing delayed by a predetermined time (T1) by the delay unit 186 from the time of brake release of the brake control command signal BK_cont is passed through the signal obtained by multiplying the disturbance estimation signal Di ^ by 1 / Kτn. , And a function to be selected by the switch unit 183.

The basic configuration of the present invention has been described above. Below, the meaning and effect of this structure are demonstrated.
<Pole arrangement of disturbance observer>
The pole (eigenvalue) of the disturbance observer 17 is a time-dependent function λ (t). The disturbance estimation characteristic of the disturbance observer 17 is determined by the arrangement of the poles on the complex plane.

In the present embodiment, the disturbance observer 17 is required to function as an unbalance torque estimator. Therefore, it is necessary to accurately and quickly estimate the unbalance torque Di acting as a step disturbance as viewed from the speed control system. The estimation characteristic of the disturbance observer 17 for estimating this may be set in a wide band as long as the stability of the system permits. That is, in the present embodiment, the eigenvalue λ (t) of the disturbance observer 17 is arranged at a point λ1 on the real axis far from the origin 0 on the left half surface of the complex plane, as shown in FIG.

<Effect of feedback control using only disturbance estimation signal>
In FIG. 5B, in order to see the effect of performing feedback control only with the disturbance estimation signal Di ^ of the present embodiment, the coefficient α of the coefficient block 184 of the pass / hold switching unit 18 in FIG. FIG. 6 shows the result of setting to zero and further disabling the sample hold unit 182 and the switch unit 183 so that the torque offset current signal iq_t * _off is only a signal obtained by multiplying the disturbance estimation signal Di ^ by 1 / Kτn. .
For comparison, the waveform when there is no feedback control of the disturbance estimation signal Di ^ is also shown in FIG.

5 (a) and 5 (b), the upper waveform indicates the time variation of the car acceleration, and the lower waveform indicates the disturbance estimation signal (= torque offset current signal). As shown in (a) in the figure, it can be seen that when there is no feedback control of the disturbance estimation signal Di ^, a peak occurs in the car acceleration when the brake is released, and a large starting shock occurs. In addition, a large rollback of about 4 cm occurs.

When the feedback control of the disturbance estimation signal Di ^ is executed, as shown in (b), a step-like waveform simulating the unbalance torque Di is applied as the torque offset current signal iq_t * _off. The shock is greatly reduced and the rollback amount is improved to less than 1 mm.

However, the car acceleration vibration (upper side) continues after the brake is released, which is problematic in terms of ride comfort. This is because the disturbance observer 17 has a function of estimating the mechanical resonance of the car 4 and the counterweight 5 (generated by elasticity in the direction of extension of the rope 3) as a disturbance, but the resonance vibration of the car 4 has not been observed. This is because it cannot be controlled. This countermeasure is performed by changing the pole arrangement described later.

<Effect of speed feedback control>
6 (a) and 6 (b) show waveforms for explaining the effect of reducing the startup shock generated when the disturbance estimation signal Di ^ is feedback-controlled by speed feedback (feedback) control.
(A) in the figure is a waveform under the same conditions as in (a) of FIG. 5, and is enlarged and displayed in the vertical axis direction. FIG. 6B shows a waveform when α of the coefficient block 184 is set to a predetermined value (in this case, −16 times). It can be seen that the feedback of the speed ω reduces the amplitude of the car acceleration (start-up shock), but persistent vibration remains. Also, the torque offset current signal iq_t * _off is macroscopically a stepped waveform but a waveform on which high-frequency vibration is superimposed.

<Effect of changing pole arrangement>
7A and 7B show waveforms for explaining the effect when the complex plane arrangement of the poles (eigenvalues) of the disturbance observer 17 is changed with time.
(A) in the figure shows the same conditions as in (a) in FIG. 6, and shows a waveform when the pole of the disturbance observer 17 is fixed at λ1 in FIG. 4, and a large starting shock occurs. . FIG. 7B shows a waveform when the pole of the disturbance observer 17 is moved to βλ1 after T0 [sec] from the brake release timing as shown in FIG. Note that β is a coefficient of 0 or more and less than 1, and βλ1 indicates that λ1 is moved to the origin side on the real axis of the left half surface (lower half surface in FIG. 8) of the complex plane.

FIG. 8 is a waveform showing an example of the time axis characteristic of the eigenvalue λ (t) of the disturbance observer 17. The definition of λ (t) in FIG.

When 0 ≦ t <T0, λ (t) = λ1
When T0 ≦ t λ (t) = βλ1
However, 0 ≦ β <1
・・・・・ Formula (1)

For the pole arrangement change shown in FIG. 8, that is, the change of the eigenvalue λ (t), the timing at which the brake control command signal BK_cont is given to the

blocks

173 and 174 in FIG. Can be changed from the high frequency side to the low frequency side.

(B) of FIG. 7 is a waveform when the eigenvalue λ (t) of the disturbance observer 17 is changed according to the definition of the above formula (1). Compared to (a) in the figure, the upper car vibration amplitude is smaller, but the vibration is sustained. In the lower torque offset current signal iq_t * _off, vibration noise after pole movement is reduced, but low-frequency vibration remains.

<Effect of waveform sample hold>
9A and 9B show waveforms for explaining the effect of the waveform sample hold on the torque offset current signal iq_t * _off by the sample hold unit 182. FIG.
(A) in the figure is the same condition as in (b) of FIG. 7 and is the same waveform as in (b) of FIG. 7 and is a waveform when the waveform sample hold of iq_t * _off is not performed. FIG. 9B shows a waveform when the waveform sample and hold of iq_t * _off is performed. The waveform sample hold is performed after a delay time T1 [sec] by the delay unit 186 from the brake release timing. This delay time T1 is selected at the timing when iq_t * _off becomes the convergence value of the stepped waveform.

10A and 10B show waveforms obtained by enlarging the time axis of FIG. The relationship between the pole arrangement change timing (T0) and the waveform sample hold timing (T1) is added.

As described above, the predetermined time T0 during which the pole (eigenvalue) is moved from the brake release timing has a function of suppressing the vibration component of iq_t * _off that is vibrational. Therefore, it is desirable to set the delay time T1 at a timing after suppressing the vibration at T0. In this case, the relationship between T0 and T1 is as follows.
T1> T0 Equation (2)

As shown in FIG. 9B, the torque offset current signal iq_t * _off is sampled and held T1 hours after the brake release timing, and the car acceleration amplitude becomes small. Further, it can be confirmed that the vibration becomes a convergence vibration and the low-frequency vibration disappears.

<Initialization of disturbance observer output>
The disturbance observer 17 is required to function as an estimator of the unbalance torque Di. Since the disturbance observer 17 includes an integral element (functional block 174) inside as shown in FIG. 2, it holds past information. Therefore, if the brake 6 is braked after the car is moved and the previous information remains in the integral element at the next start-up, accurate estimation is hindered.

In order to prevent this, when the brake 6 is moved after the car 4 is moved, the outputs of the disturbance observer 17 and the pass / hold switching unit 18 may be initialized.
If initialization is performed before starting in this way, it is possible to accurately estimate the unbalance torque Di of the disturbance observer 17, and an accurate torque offset current signal iq_t * _off is output, thereby reducing start shock and rollback. Can be suppressed.

According to the above configuration, the disturbance observer 17 estimates the step-like unbalance torque acting on the speed control after releasing the brake at high speed and accurately, and cancels the disturbance estimation signal Di ^, the speed signal ω, and the brake. By generating and returning a torque offset current signal based on the control command signal, it is possible to suppress the starting shock and the rollback amount.

Embodiment 2. FIG.
In the first embodiment, the motor drive current signal iq is used as the input signal to the disturbance observer 17, but instead of this, a torque current command signal iq_t * may be used as shown in FIG. According to this configuration, since the calculation of the disturbance observer 17 is configured only with the internal signal of the calculation unit, the system can be created more easily.

The disturbance observer 17 in this case is as shown in FIG. Only the input signal of the disturbance observer 17 is changed from the motor drive current signal iq to the torque current command signal iq_t *, and the configuration is the same as that of the first embodiment shown in FIG. 1 and FIG.

In the above-described embodiment, the disturbance observer 17 is described and explained as an analog system. However, the disturbance observer 17 may be digitized and configured using a digital operation element such as a digital signal processor and a microcomputer.

Embodiment 3 FIG.
In the present embodiment, the end timing of the speed feedback control is limited, thereby enabling higher performance and stable operation.

That is, in FIG. 1, the speed of the motor 1 is obtained by inputting detection information of the pulse encoder 11 that detects the rotation angle of the motor 1 to the speed calculation unit 12. The pulse encoder 11 outputs and detects a 1-pulse waveform every time the rotation angle of the motor 1 reaches a predetermined value. In such a configuration, when the rotational speed of the motor 1 is slow, that is, when the change of the rotational angle is slow, the pulse detection period of the pulse encoder 11 becomes long. Therefore, since the detection update cycle of the motor angle detection signal that is an input signal of the speed calculation unit 12 becomes longer, a detection time delay occurs in the speed signal ω that is the output of the speed calculation unit 12.

When the speed of the motor 1 approaches zero, the delay in the detection time of the speed signal ω increases, and the stability of the speed feedback control based on the speed signal ω may be impaired. This tendency becomes more prominent as the speed feedback gain (absolute value of α of the coefficient block 184 shown in FIG. 3) is increased. On the other hand, the larger the speed feedback gain is, the smaller the startup shock becomes, and the stability and the startup shock have a trade-off relationship.
Therefore, in the present embodiment, a configuration that achieves both stability and suppression of startup shock will be described.

(A) of FIG. 13 shows the transient behavior when the speed feedback gain is set large with respect to the configuration described in the first or second embodiment of the present invention in order to improve the starting shock immediately after the brake is released. From the top of the waveform, the time axis waveform of the car acceleration, torque offset current signal, and motor speed ω is shown.

か Although the car acceleration immediately after the brake is released is kept small, the amplitude of the car acceleration increases during the period from the brake release timing to the pole movement timing T0. This is because, as shown in the bottom waveform of (a), the motor speed ω has become zero, the speed feedback control has become unstable, the motor speed ω has oscillated, and the torque offset current signal iq_t * _off has also oscillated. It is.

This vibration is a result of the stability of the control being impaired because the speed of the motor 1 is reduced and the detection time delay of the motor speed ω is increased. Therefore, as a countermeasure, the speed feedback control may be stopped before the stability of the control is impaired. Therefore, the present embodiment has a configuration in which the speed feedback control is stopped at the timing when the speed ω of the motor 1 converges to near zero.

The configuration of the pass / hold switching unit 18 according to the present embodiment shown in FIG. 14 is different from the configuration described with reference to FIG. 3 in the first or second embodiment of the present invention in the signal path of the speed signal ω.

That is, the speed signal ω is multiplied by α in the coefficient block 184 and input to the second switch unit 187. The second switch unit 187 is switched ON / OFF by the output signal of the second delay unit 188.

FIG. 15 is a time waveform showing the relationship between the delay amount T2 of the second delay unit 188 and the delay amount T0 for determining the polar movement timing of the disturbance observer 17. As shown in FIG. 15A, the input to the second delay unit 188 is a brake control command signal BK_cont, which is a signal delayed by T0 from the brake release timing.

As shown in FIG. 15B, the switch unit 187 adds the speed signal ω having the gain α of the coefficient block 184 to the output of the coefficient block 181 in the addition block 185 until the period T2 elapses from the brake release timing. Is done. When the period T2 has elapsed, the speed signal ω is set to zero. The output of the adder 185 is given as one input signal A of the switch 183.
The other configuration is the same as the configuration shown in FIG.

With such a configuration, a signal A obtained by adding the signal obtained by multiplying the disturbance estimation signal Di ^ by 1 / Kτn and the signal obtained by multiplying the speed signal ω by α by the adder 185 is set as the torque offset current signal iq_t * _off, or The signal A obtained by multiplying the disturbance estimation signal Di ^ by 1 / Kτn is used as the torque offset current signal iq_t * _off, or the signal obtained by multiplying the disturbance estimation signal Di ^ by 1 / Kτn is delayed from the brake release timing by the brake control command signal BK_cont. Whether the signal B sampled and held by the sample and hold unit 182 at the timing delayed by the unit (first delay unit) 186 by the predetermined time (T1) is used as the torque offset current signal iq_t * _off. A function to be selected by the switch unit 187 is realized.

The selection by the switch unit 183 and the second switch unit 187 is performed by a signal obtained by delaying the brake release signal by the brake control command signal BK_cont by a predetermined time (T1, T2).

Since the speed feedback control is set to function faster than the response time of the disturbance observer 17 to the disturbance, the convergence time of the step response becomes shorter than the convergence time of the disturbance observer 17. Therefore, the relationship between the delay amounts of the two is as follows.
T2 <T0 Equation (3)

The delay amount T2 for determining the end timing of the speed feedback control may be set as follows, for example. FIG. 13B shows a transient response waveform when the delay amount T2 for determining the speed feedback control end timing is shorter than the pole movement timing T0. T2 at this time is selected in a period in which the motor speed ω converges to approximately zero after the peak of the motor speed ω exceeds the peak from the brake release timing.

More specifically, the delay time T2 sets a threshold value at a speed higher than the motor speed ω at which the speed feedback control becomes oscillating with respect to the motor speed ω, and the motor speed ω has a peak after the brake release timing. It is set to the time from exceeding the threshold value to below the above threshold. With this setting, it is possible to suppress the vibration of the torque offset current signal and the motor speed ω and the increase in the car acceleration (starting shock) resulting therefrom during the period T0 seen in FIG. This is shown in the upper waveform of FIG.

By configuring the control system in this way, it is possible to exert the effect of suppressing the starting shock by speed feedback control, and to avoid an unstable phenomenon due to speed detection delay in the vicinity of the zero speed of speed feedback control. Can do.

Embodiment 4 FIG.
In the first to third embodiments, the disturbance observer 17 has a configuration in which the pole arrangement is changed. Instead, a similar function can be realized only by adding a simple low-pass filter to the output stage of the disturbance observer 17. it can. According to this configuration, it is not necessary to change the pole arrangement of the disturbance observer 17 which is a complicated calculation process, and it is only necessary to change the cutoff frequency of the low-pass filter, so that the system can be created more easily.

The disturbance observer 17 in this case is as shown in FIG. Reference numeral 17a denotes a disturbance observer calculation function block, and the pole is a fixed pole that is λ1 and does not vary with time. Reference numeral 17b denotes a band limiting filter connected in series to the output of the disturbance observer calculation function block 17a, which is a primary low-pass filter in this example. The parameter that determines the cutoff band of the band limiting filter 17b is the cutoff frequency λ (t). λ (t) is changed to a small value after T0 [sec] from the brake control command signal BK_cont, and as a result, the passband is lowered. The definition of T0 is the same as in the first to third embodiments. With this configuration, the disturbance estimation band of the disturbance observer 17 can be changed.

FIG. 17 shows a specific time axis waveform diagram of the time change of the cutoff frequency of the band limiting filter 17b. The definition of λ (t) in FIG.

When 0 ≦ t <T0, λ (t) = | λ2 |
When T0 ≦ t λ (t) = | βλ1 |
Here, λ2 is selected to be a value that can ignore the influence around the phase with respect to λ1, which is the pole of the disturbance observer 17 described in the first to third embodiments. For example, it may be set to 10 times with respect to λ1. Β is the same as that described in the first to third embodiments.

Since the output of the disturbance observer 17 is band-limited by the configuration as described above, the disturbance estimation band is changed from the high frequency side to the low frequency side in the same manner as the pole placement change of the disturbance observer 17 described in the first to third embodiments. The effect of changing to can be obtained.

In the first to fourth embodiments, the brake control command signal BK_cont is used. Needless to say, any other signal may be used as long as it detects that the brake 6 has been released. For example, a speed signal ω that changes synchronously when the brake is released may be used, and a signal based on this may be substituted. More specifically, the speed signal ω changes to zero when the brake 6 is functioning and changes abruptly when the brake 6 is released. Can be substituted.

1 motor, 2 sheaves, 3 ropes, 4 cages, 5 balancing weights, 6 brakes, 7 controllers, 8 brake control units, 9 current control units, 10 current detection units, 11 pulse encoders, 12 speed calculation units, 13 speed commands Generation unit, 14 subtraction unit, 15 speed control unit, 16 addition unit, 17 disturbance observer, 18 pass / hold switching unit.

Claims

A current detection unit that detects a drive current of a motor that rotationally drives a sheave in which a car and a counterweight are suspended by a rope;
A speed calculation unit that outputs a speed signal of the motor from an output of a rotation amount detection unit that detects the rotation amount of the motor;
A speed command generator for generating a speed command signal for the motor;
A speed control unit that outputs a torque current command signal from the speed command signal and the speed signal;
A current controller that drives the motor such that the drive current follows the torque current command signal;
An unbalance torque estimator that estimates an unbalance torque that is a weight difference between the car and the counterweight based on the drive current or the torque current command signal and the speed signal;
As the torque offset current command signal, a signal obtained by adding the output signal of the unbalance torque estimator and a value proportional to the speed signal is output, or the unbalance torque estimator is output after the brake that brakes the rotation of the motor is released. A switching unit for selecting whether to output the output signal of the balance torque estimator;
An elevator control device comprising: an addition unit that adds the torque offset current command signal output from the switching unit to the torque current command signal that is an input of the current control unit.
The unbalance torque estimator is a disturbance observer that models electrical characteristics and mechanical characteristics of the motor and the sheave, and inputs the drive current or the torque current command signal and the speed signal, and the unbalance torque The elevator control device according to claim 1, further comprising a function of changing a disturbance estimation band after a brake that brakes rotation of the motor is released.
The elevator according to claim 2, wherein the disturbance observer changes the disturbance estimation band from a high frequency side to a low frequency side after a first elapsed time (T0) from a timing at which a brake that brakes rotation of the motor is released. Control device.
The switching unit holds the disturbance estimation signal after a second elapsed time (T1) longer than the first elapsed time (T0) from a timing at which a brake that brakes rotation of the motor is released. The elevator control device described in 1.
The switching unit is
As the torque offset current command signal, a signal obtained by adding the output signal of the unbalance torque estimator and a value proportional to the speed signal is used as a third time from the release timing of the brake that brakes the rotation of the motor. The elevator control device according to claim 1, wherein zero is set after time (T2).
The unbalance torque estimator is a disturbance observer that models electrical characteristics and mechanical characteristics of the motor and the sheave, and inputs the drive current or the torque current command signal and the speed signal, and the unbalance torque Is output as a disturbance estimation signal,
Furthermore, a low pass filter connected in series to the output of the disturbance observer is provided,
The elevator control device according to claim 1, wherein the low-pass filter has a function of changing a disturbance estimation band of the disturbance estimation signal after a brake that brakes rotation of the motor is released.
The elevator control device according to claim 6, wherein the low-pass filter changes the disturbance estimation band from a high frequency side to a low frequency side after a first elapsed time from the release of a brake that brakes rotation of the motor. .
The elevator control device according to claim 1, wherein the torque current command signal input to the unbalance torque estimator is a signal input to the current control unit.