JPH10338427A - Drive controller of elevator - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To control an electric motor with high efficiency and to suppress vertical vibration of a car. A power converter, an AC motor, a car, an elevator speed command generating means,
In an elevator drive control device provided with a speed control means 140 for generating a torque command, a motor current detection means 1
50 and means 15 for estimating the generated torque from the detected current value
2, a means 160 for controlling the torque command and the estimated generated torque to coincide with each other, and an electric power such that the torque current component and the exciting current component of the motor current have a predetermined relationship based on the output of the means 160. Means 170 for controlling the converter
To 230, a first means 300 for estimating the motor load torque from the motor speed, and a second means 400 for estimating the motor load torque from the speed command, the output of the first means or the output of the second means and the means 152, wherein a deviation from the output of 152 is injected into the torque command.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive control device for an elevator, and more particularly to an elevator drive control device that drives an AC motor for driving an elevator with high efficiency and suppresses vertical vibration of a car. The present invention relates to a drive control device.

[0002]

2. Description of the Related Art In order to improve the efficiency of a drive system of an elevator, Japanese Patent Laid-Open No. 59-149283 discloses a conventional technique in which a deviation between a speed command and an actual speed of an elevator is within a predetermined range. It is disclosed that the frequency is fixed at a predetermined value.

In order to improve the speed control performance with respect to load torque fluctuations for an AC motor, Japanese Patent Laid-Open No.
Japanese Patent Application Laid-Open No. 125187/1987 discloses that a control system for estimating a load torque of a motor from a detected motor speed value and a motor torque command value and adding the estimated load torque to a torque command to reduce torque pulsation is provided.

[0004]

Generally, in an elevator, the number of passengers in a car constantly changes, so that the load applied to a drive motor constantly changes. As a result, the torque to be generated in the drive motor must be changed according to the load, and at the same time, the torque must be generated such that the speed follows the speed command.

The former conventional technique does not maintain high efficiency regardless of the load applied to the motor.

In the latter prior art, no consideration is given to the load of a mechanical system, such as an elevator, whose load constantly changes and tends to vibrate, and no consideration is given to improving the efficiency.

The present invention has been made in consideration of the above-described problems, and enables the driving motor to be driven with high efficiency even when the load applied to the driving motor changes, including, for example, a transient state. An object of the present invention is to provide an elevator drive control device capable of suppressing vertical vibration of a car.

[0008]

In order to solve the above problems, the present invention employs the following means.

A power converter which outputs a variable voltage / variable frequency alternating current under control, an AC motor which is supplied with power from the power converter and is driven at a variable speed, a car driven up and down by the motor, and the speed of the elevator A speed command means for generating a command, a means for detecting a motor current in an elevator having a speed control means for generating a torque command so that the speed of the motor follows the speed command, and a detected current value Generated torque estimating means for estimating the generated torque of the electric motor or its equivalent value, torque control means for controlling the torque command so as to match the estimated generated torque or its equivalent value, and this torque control means The power converter is controlled such that the torque current component and the excitation current component of the motor current have a predetermined relationship based on the output of Stage, first load torque estimating means for estimating the load torque of the electric motor or its equivalent value from the speed of the electric motor, and second load torque estimating means for estimating the load torque of the electric motor or its equivalent value from the speed command And a deviation between the output of the first load torque estimating means or the output of the second load torque estimating means and the output of the generated torque estimating means is injected into the torque command.

[0010] Also, a power converter which outputs a variable voltage / variable frequency alternating current under control, an AC motor which is supplied with power from the power converter and is driven at a variable speed, a car and an elevator which are driven up and down by the motor, A speed command means for generating a speed command, and a means for detecting a motor current in an elevator including a speed control means for generating a torque command so that the speed of the motor follows the speed command. Generated torque estimating means for estimating the generated torque of the electric motor or its equivalent value from a current value; torque control means for controlling the torque command so as to match the estimated generated torque or its equivalent value; The power converter is controlled based on the output of the control means so that the torque current component and the exciting current component of the motor current have a predetermined relationship. Means for estimating the load torque of the electric motor or its equivalent value from the speed of the electric motor, and second load torque estimating means for estimating the load torque of the electric motor or its equivalent value from the speed command. Means, first signal adjusting means for adjusting the output of the first load torque estimating means, second signal adjusting means for adjusting the output of the second load torque estimating means, and the first signal A third signal adjusting unit for adjusting a deviation between an output of the adjusting unit or an output of the second signal adjusting unit and an output of the generated torque estimating unit, wherein an output of the third signal adjusting unit is It is characterized by injection into the torque command.

Further, the first signal adjusting means and the second signal adjusting means are controlled to be switched according to the speed command.

Further, the first load torque estimating means and the second load torque estimating means are adjusted in accordance with the load fluctuation of the elevator.

Further, means for calculating a moment of inertia is provided, and the first load torque estimating means and the second load torque estimating means each use the calculated moment of inertia for estimating a load torque. And

[0014] Further, acceleration command means for generating an acceleration command is provided, wherein the speed command means calculates the acceleration command to generate the speed command, and the second load torque estimating means replaces the speed command. The load torque of the electric motor or its equivalent value is estimated using the acceleration command.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is an overall configuration diagram of a drive control device for an elevator according to this embodiment. First, an outline of drive control of the elevator drive control device will be described with reference to FIG. In the drawing, reference numeral 240 denotes a vibration suppression signal generating means.

The AC voltage of the AC power supply 10 is
Is converted to a DC voltage, and this DC voltage is smoothed by the smoothing capacitor 30. The smoothed DC voltage is further
The WM inverter 40 converts the voltage into a variable voltage, variable frequency alternating voltage flow. The converted AC voltage is supplied to an induction motor (IM) 60 and driven at a variable speed. The torque generated by the induction motor 60 is transmitted to a sheave (a sheave) 70 via a gear (not shown) directly connected to a rotor (rotor) of the induction motor. Then, the rope connecting the car 90 is operated to drive the car 90 up and down.

As described above, the weight difference between the counterweight 80 and the car 90 is applied to the induction motor 60 as a load (load). The load constantly changes when the number of passengers changes, and the motor is driven in most of the operation. It is less than half of the output. Therefore, if the driving efficiency of the induction motor 60 can be increased during driving (transient state) and with a light load, power saving of the elevator drive system can be achieved.

The control for increasing the efficiency of the elevator drive control device according to the present embodiment has already been described in Japanese Patent Application No. Hei.
As described in detail in Japanese Patent No. 82342,
Here, the outline will be described.

In the elevator, the acceleration pattern is determined by the acceleration pattern generating means 110 in consideration of the riding comfort. The acceleration pattern generated from the means 110 is input to the speed command generating means 120. This means 120, and converts the speed command omega _R by integrating the acceleration pattern. The speed command ω _R is detected by the speed detector 100 attached to the induction motor 60 in the adder / subtractor 130, and the induction motor 6
It is added to or subtracted from the rotational angular velocity ω _M of the rotor of 0 to generate a velocity deviation. Based on the speed deviation, the speed control means 140 generates a torque command τ _R for determining a torque to be generated by the induction motor 60 so that the speed deviation is eliminated.

The torque command τ _R is added and subtracted by the adder / subtractor 131 from the generated torque estimating means 152 with the instantaneous torque τ _M ^推定 estimated to be generated inside the motor at the present time.

[0022] The torque component current I _t and secondary magnetic flux phi ₂ necessary for estimating the instantaneous torque tau _M ^∧, the current sensor 5
0, 51, 52, the primary currents i _u ,
i _v, based on i _w, the excitation component / torque current detection means 15
A torque current I _t computed in 0, also an excitation component / torque current computed in further secondary magnetic flux calculation means 151 an exciting component current I _m which is calculated in the detecting means 150 secondary magnetic flux phi ₂ Used.

The torque command τ _R and the estimated instantaneous torque τ
Torque deviation between the _M ^∧ are input to the torque control means 160, torque command so that the torque deviation becomes zero tau _R
To determine the amount of operation τ ^*.

The manipulated variable τ ^* is determined by the torque current command calculating means 1
At 70, the torque current command _Im ^* is calculated by calculating with the secondary magnetic flux φ ₂ and various circuit constants, and is input to the current command calculation means 200.

On the other hand, exciting current / torque current ratio determining means 1
In 80, loss in the induction motor 60 is determined the ratio of the exciting component current I _m and the torque component current I _t so as to minimize, determines the excitation current command I _mR by multiplying a torque current command I _t ^* in the ratio I do. Exciting current command I _mR in adder-subtracter 132, excitation component / torque current and the exciting component current I _m that is detected from the detection means 150 are added or subtracted, the excitation current control means 190 so that the deviation becomes zero is further output Generates a new excitation current command compensation value _Im ^* .

[0026] In current calculation means 200, the torque current command I _t ^*, exciting current command compensation value I _m ^* and the rotation angular velocity ω
Based on _M, 3-phase AC current command i _u ^*, i _v ^*, generates the i _w ^*, Further, in the current control unit 210, the alternating current command ^{_{i u *, i v *,}} i w * 3 The phase alternating currents i _u , _iv ,
controlled to match the i _w, further modulated wave generating means 2
In 20, the three-phase modulation voltage V _u ^*, V _v ^*, generates a V _w ^*. The three-phase modulation voltage is input to the PMW signal generator 230, compared with the carrier, generates a PMW signal, and input to the gate of the PMW inverter 40.

As a result, according to the present embodiment, a combined current of the torque current and the electromagnetic current that always provides the highest efficiency flows inside the induction motor 60, and this relationship is independent of the load state. Therefore, the induction motor 60 can always be driven with the highest efficiency including the transient state. In particular, in an elevator drive system in which the number of passengers in the car 90 constantly fluctuates and the load torque applied to the induction motor 60 constantly fluctuates as in the present embodiment, the average applied to the induction motor 60 during operation is average. Such a load is often driven in a light load state that is equal to or less than half the rated torque of a general electric motor.

Next, suppression of vertical vibration of the car according to the present embodiment will be described with reference to FIGS.

FIG. 2 shows the vibration suppression signal generating means 2 shown in FIG.
It is a block diagram of 40.

Generally, an elevator is located in a region where the natural vibration frequency of the machine is likely to resonate with the driving frequency of the motor, which is excited by the torque ripple of the motor and the like, causing vertical vibration of the car and deteriorating the riding comfort of the elevator. . There is a mode in which this vibration is superimposed on the motor speed. Therefore, if the load torque vibration can be estimated using the motor detection speed and the like, the phase of the estimated value can be inverted and injected into the torque command, Vibration can be suppressed and good ride comfort can be ensured.

[0031] In Figures 1 and 2, 133 subtracter, 300 is a first load torque estimating means for outputting a first load torque estimate tau ^∧ from the motor detection speed omega _M, 3
01 is a first signal adjusting means for adjusting the gain K ₁ of the _first estimated load torque τ ^∧ , and 400 is a second load torque for outputting the second estimated load torque τ ^{か ら} from the speed command ω _R. Estimating means 401 is a second load torque estimated value τ ^∧∧
A second signal adjusting means for adjusting the gain K _2, 500 is a signal for operating one of the first signal conditioner 301 and a second signal conditioner 401 by the value of the speed command omega _R The signal determining means 600 adjusts the estimated disturbance torque estimated value τ _d ^し and adjusts the vibration suppression signal τ _sup
Is a third signal adjusting means for outputting the signal.

In general, assuming that the generated torque of the motor is τ _M and the disturbance torque appearing on the motor shaft is τ _d , the following relationship holds for the load torque τ applied to the motor.

Τ _M + τ _d = τ (1) Here, assuming that the total moment of inertia of the mechanical system around the motor axis is J and the Laplace operator is s, the relationship between the load torque τ and the motor speed ω _M ′ Then, the following relationship holds.

Τ / (J · s) = ω _M ′ (2) Normally, J is known at the mechanical system design stage, and the motor speed ω _M ′ and the motor detection speed ω _M can be regarded as equal. in the load torque estimating means 300 of 1, the first load torque estimate tau ^∧ load torque tau using motor detection speed omega _M can be calculated by the following equation.

[0035] _{^{τ ∧ = J · ω M ·}} s (3) On the other hand, from the generated torque estimating means 152 generates torque estimate tau _M ^∧ are determined. Accordingly, the disturbance torque estimate tau _d ^∧ of the disturbance torque tau _d Can be obtained from Expressions (1) and (3) by the following expression.

[0036] In the equation (2), the motor speed ω _M ′ is the speed command ω
_{In the} case of following the _R well, it can be replaced by τ / (J · s) = ω _R (5).
At 00, a second estimated load torque ^ττ of the load torque τ can be determined by the following equation.

[0037] _{^{τ ∧∧ = J · ω R ·}} s (6) Thus, the disturbance torque estimate tau _d ^∧ disturbance torque tau from equation (1) and (6) can be obtained by the following equation.

[0038] As described above, as shown in Expressions (4) and (7), two types of estimated disturbance torque values τ _d ^} are obtained. This disturbance torque estimated value τ _d ^} is input to the third signal adjusting means 600, and the noise component is removed by a low-pass filter, and the gain and the phase are adjusted so that the vertical vibration of the car 90 is reduced. It is output as the obtained vibration suppression signal τ _sup .

By injecting this τ _sup into the torque command τ _R , a torque command τ _R −τ _sup that can suppress vibration is generated.

Here, in generating the vibration suppression signal τ _sup , whether to use the estimated disturbance torque τ _d ^に based on equation (4) or the estimated disturbance torque τ _d ^{基 づ く} based on equation (7) , in signal determination unit 500, is determined by whether or exceeds a predetermined speed with the speed command omega _R, the first signal adjusting means in accordance with the determination result 301
Alternatively, the second signal adjusting means is switched and selected.

Normally, in a region where the speed changes abruptly at the time of startup or the like, the estimated disturbance torque τ _d ^∧ obtained from the equation (7) is used.
Is used. In other regions, the estimated disturbance torque τ _d ^から obtained from the equation (4) is used, and the speed command ω _R that can be controlled in a feedforward manner is used. It is possible to reduce the control delay due to the detection delay of _M or the like.

By the way, in general, the acceleration pattern (command) of the elevator is determined so as to obtain the optimum riding comfort.
It is generating speed command ω _R by integrating it. In the present embodiment, the instantaneous torque of the motor is generated such that the motor speed ω _M ′ follows this speed command ω _R regardless of the load state. The ride comfort is further improved, and an effect that vibration due to an impact disturbance such as a shock due to an inaccurate start-up compensation at the time of start-up can be quickly suppressed is also produced.

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 160 is not necessarily required, and the output of the adder / subtractor 131 may be directly input to the torque current command calculation means 170. Although the third signal adjusting means 600 is provided with a low-pass filter, the motor detection speed ω _M output from the speed calculating means 121 and the generated torque estimated value τ _M ^出力 output from the generated torque estimating means 152 are used. Need not be provided as long as the noise component is removed. When a steady error appears in the vibration suppression signal τ _sup , a band-pass filter may be used. Furthermore, the estimated load torque τ ^∧ (or τ ^∧∧ )
And if there is a phase difference in the generated torque estimate tau _M ^∧, first
A phase adjuster can be added to the output of the load torque estimating means 300 or the second load torque estimating means 400 to eliminate the phase difference. Further, it can be gradually changed in order to eliminate a shock caused by switching between the first signal adjusting means 301 and the second signal adjusting means 401. Furthermore, the input signal determination unit 500 for switching the first and second signal adjusting unit 301 and 401 is not limited to the speed command omega _R, the motor detection speed omega _M, the output of the acceleration pattern generating means 110, or The elapsed time from the start of rotation of the induction motor 60 may be used.

Next, a second embodiment of the present invention will be described with reference to FIG.

FIG. 3 is a block diagram showing another configuration example of the vibration suppression signal generating means 240 shown in FIG.

This embodiment is different from the first embodiment in that the first embodiment has a second load torque estimating means 40.
0, whereas that with the speed command value omega _R obtained by calculation by the speed command calculation unit 120 outputs the acceleration pattern 110, in this embodiment, directly, using the output of the acceleration pattern generating means 110 Differs in that

Here, the second load torque estimating means 400
In the above, if the acceleration command is α _R , the second load torque estimated value τ ^∧∧ can be obtained by the following equation.

Τ ^∧∧ = J · α _R (8) As a result, as shown by the equation (8), the second load torque estimating means 400 can eliminate the differential element, so that the first embodiment The operation can be simplified as compared with

Next, a third embodiment of the present invention will be described with reference to FIG.

FIG. 4 is a block diagram showing still another example of the configuration of the vibration suppression signal generating means 240 shown in FIG.

In FIG. 4, reference numeral 700 denotes a load detector for detecting the load in the car 90, and 701 a load detector 700.
702 is a load variation calculating means for obtaining a load variation △ J of the inertia moment J from the operation amount τ ^* of the torque command τ _R output from the torque control means 160 and the motor detection speed ω
Initial inertia value calculating means 703 for calculating the moment of inertia J from _M is a data holding means 703 for holding the moment of inertia J calculated and updated. Other parts are shown in Fig. 1.
Has the same function as that shown in FIG. The difference between the present embodiment and the first embodiment is that the first embodiment uses the moment of inertia J in a fixed manner, while the present embodiment changes the inertia moment J over time and the number of passengers. The point is that the moment of inertia J adjusted according to the change due to the fluctuation is used.

In the elevator, since the moment of inertia J always fluctuates due to the fluctuation of the number of passengers in the car 60, the load in the car 90 is detected by the load detector 700, and the output of the load fluctuation calculating means 701 is calculated by the load fluctuation calculating means 701. The load variation ΔJ of the inertia moment J is obtained.

On the other hand, the initial inertia value calculating means 702 detects the motor reached by the induction motor 60 when a constant manipulated variable τ ₁ ^* , which is the manipulated variable τ ^* of the torque command τ _R , is given for a fixed period t _1. If the speed is omega _M1, it is possible to determine the moment of inertia J from the following equation.

J = τ ₁ ^* · t ₁ / ω _M1 (9) The moment of inertia J is calculated immediately after installation of the elevator or periodically or irregularly after operation, by calculating
The data is held in the data holding unit 703, and is used for calculating the load estimation torque of the first load torque estimation unit 300 and the second load torque estimation unit 400.

As a result, in the calculation of the load torque estimation in the first and second load torque estimation means 300 and 400, the load variation △ J was adjusted from the inertia moment J held in the data holding means 703. The moment of inertia J ± △ J is used.

The other processing is the same as that of the first embodiment, and the description is omitted.

As described above, according to the present embodiment, since the moment of inertia more realistic is used, it is possible to always accurately estimate the load torque, and it is possible to prevent the starting compensation from being degraded due to aging and the like, and to increase the car vibration. In addition to the suppression, there is an effect that the start compensation adjustment immediately after the installation of the elevator and the adjustment items at the time of maintenance and inspection can be reduced.

In this embodiment, the means for adjusting the moment of inertia J is provided at two points, that is, the load variation calculating means 701 and the initial inertia value calculating means 702, but accurate load can be obtained by using only one of them. The torque can be estimated, and a vibration suppressing effect can be exhibited.

As described above, according to this embodiment, in a region where the speed fluctuates rapidly, such as at the time of starting, the load torque is estimated from the speed command value instead of the detected motor speed value, and the load torque is estimated. Since a deviation from the estimated torque value is calculated, and the deviation is adjusted and injected into the torque command value, it is possible to suppress a vibration caused by a shock at the time of a sudden speed change.

Outside the region where the speed fluctuates abruptly, such as at the time of startup, the torque vibration component included in the load torque applied to the motor is calculated by using the estimated load torque obtained from the detected motor speed and the load, and the motor. It is estimated from the deviation from the generated torque estimated value. The estimated value of the torque vibration component is inverted to reverse the phase so as to cancel the vibration, and is adjusted so as to make the magnitude of the vertical vibration of the car smaller, preferably to be the minimum, and is injected into the torque command value.

[0061]

According to the present invention, in response to the torque command, the exciting component current and the torque component current are caused to flow in the motor at a ratio that can follow the motor with high efficiency. Since the vibration component is estimated and injected into the torque command as the vibration suppression signal, the vibration of the car can be suppressed while controlling the electric motor with high efficiency including the transient state.

[Brief description of the drawings]

FIG. 1 is a block diagram of an elevator drive control device according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a vibration suppression signal generator 240 shown in FIG.

FIG. 3 is a block diagram of a vibration suppression signal generation unit 240 according to a second embodiment of the present invention.

FIG. 4 is a block diagram of a vibration suppression signal generation unit 240 according to a third embodiment of the present invention.

[Description of Signs] 40 PMW inverter 60 Induction motor 90 Riding car 100 Speed detector 110 Acceleration pattern generating means 120 Speed command calculating means 121 Speed calculating means 130, 131, 132, 133 Adder / subtractor 140 Speed control means 150 Excitation / torque Current detecting means 152 generated torque estimating means 160 torque controlling means 170 torque current command calculating means 180 exciting current / torque current ratio determining means 190 exciting current controlling means 200 current command calculating means 210 current controlling means 220 modulated wave generating means 230 PWM signal Generating means 300 First load torque estimating means 301 First signal adjusting means 400 Second load torque estimating means 401 Second signal adjusting means 500 Signal determining means 600 Third signal adjusting means 700 Load detector 701 Load fluctuation Minute Calculation means 702 initial inertia calculating means 703 data holding means

Claims (6)

[Claims] 1. A power converter which outputs a variable voltage / variable frequency alternating current under control, an AC motor which is supplied with power from the power converter and is driven at a variable speed, and a car and an elevator which are driven up and down by the motor. A speed command means for generating a speed command, and a speed control means for generating a torque command so that the speed of the electric motor follows the speed command. Generated torque estimating means for estimating the generated torque of the electric motor or its equivalent value from a current value; torque controlling means for controlling the torque command to be equal to the estimated generated torque or its equivalent value; The power converter is controlled based on the output of the control means so that the torque current component and the excitation current component of the motor current have a predetermined relationship. Means, first load torque estimating means for estimating the load torque of the motor or its equivalent value from the speed of the electric motor, and second load torque estimating means for estimating the load torque of the electric motor or its equivalent value from the speed command. And an error between the output of the first load torque estimating means or the output of the second load torque estimating means and the output of the generated torque estimating means is injected into the torque command. Drive control device. 2. A controlled power converter for outputting a variable voltage / variable frequency AC, an AC motor supplied with power from the power converter and driven at a variable speed, and a car and an elevator driven up and down by the motor. A speed command means for generating a speed command, and a speed control means for generating a torque command so that the speed of the electric motor follows the speed command. A generated torque estimating means for estimating a generated torque of the electric motor or its equivalent value from a current value; a torque control means for controlling the torque command to be equal to the estimated generated torque or its equivalent value; The power converter is controlled based on the output of the control means so that the torque current component and the excitation current component of the motor current have a predetermined relationship. Means, first load torque estimating means for estimating the load torque of the motor or its equivalent value from the speed of the electric motor, and second load torque estimating means for estimating the load torque of the electric motor or its equivalent value from the speed command. A first signal adjusting unit for adjusting an output of the first load torque estimating unit; a second signal adjusting unit for adjusting an output of the second load torque estimating unit; and the first signal adjusting. Means for adjusting the deviation between the output of the means or the output of the second signal adjusting means and the output of the generated torque estimating means. The output of the third signal adjusting means is An elevator drive control device characterized by injecting torque commands. 3. The elevator drive control device according to claim 2, wherein the first signal adjustment unit and the second signal adjustment unit are switched and controlled in accordance with the speed command. . 4. The method according to claim 1, wherein
The drive control device for an elevator according to one of the claims, wherein the first load torque estimating means and the second load torque estimating means are adjusted in accordance with an elevator load variation. 5. The method according to claim 1, wherein
In the claims, means for calculating a moment of inertia is provided, and the first load torque estimating means and the second load torque estimating means each use the calculated moment of inertia for estimating a load torque. A drive control device for an elevator. 6. The method according to claim 1, wherein
In Claims, acceleration command means for generating an acceleration command is provided, wherein the speed command means calculates the acceleration command to generate the speed command, and the second load torque estimating means replaces the speed command. An elevator drive control device for estimating the load torque of the electric motor or its equivalent value using the acceleration command.