JPH02214486A - Controller for elevator - Google Patents

Abstract

PURPOSE:To accelerate the rise of a magnetic flux and to output a correct torque by determining a conversion coefficient of an exciting current command calculated by an exciting current command calculator or a torque current command in response to the exciting component of a three-phase primary current transformed by a coordinates transformation circuit. CONSTITUTION:When a start command is output, a d-axis current command Id* rises simultaneously upon a start command. On the other hand, the output signal 15a of a speed control calculator 15 is zero up to a time point Ta when a speed command 13a for starting is generated even if a start command is input, and thereafter raised in response to a deviation from a speed detection signal 5a. The output signal 16a of an unbalanced load compensator 16 stepwisely rises to the compensating value of the unbalanced load together with the start command. A signal 17a of the addition result of the output signals 15a and 16a is multiplied by a target value of transformation coefficients 32, further divided by Id* to obtain a torque current command Iq*, thereby generating torque tau proportional to the Id*.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an elevator control device that performs variable voltage and variable frequency control (VVVF control) on an induction motor for driving an elevator.

[Prior Art] Conventional elevator control devices of this type include, for example, Japanese Patent Laid-Open No. 60-16184 and Japanese Patent Laid-Open No. 63-52.
The technique disclosed in Japanese Patent No. 684 can be mentioned.

FIG. 8 is a block diagram showing this conventional elevator control device together with a car balancing system, FIG. 9 is a block diagram showing details of the elevator control device, and FIG. 10 is the control for the elevator shown in FIG. In the device, in particular, a block diagram showing the internal configuration of the magnetic flux calculation circuit, FIG.
Block diagram showing the internal configuration of the shaft current command calculation circuit, 1st
FIG. 2 is a characteristic diagram showing the excitation current command output from the d-axis current command calculation circuit.

In Figure 8, (1) is the induction motor, (2) is the elevator car, (3) is the counterweight, (4) is the main lobe, and (5) is the speed detector attached to the induction motor (1). , (6) is a load detection device that detects the load of the car (2), (7) is a three-phase AC power supply, (8) is a converter that converts three-phase AC to DC, (9) is a smoothing capacitor, ( 1
0) is an inverter that converts direct current to alternating current, and (11) is a current detector.

(12) is a microcomputer, which sends the output signals of the speed detector (5), load detector (6) and current detector (11) to the central processing unit (CPU) via an interface (■/F). and read-only memory (R
A command signal to the inverter (10) is calculated and generated using programs and constants stored in the read/write memory (RAM).

In FIG. 9, (5a) is a speed detection signal that is the output of the speed detector (5), (6a) is a load detection signal that is the output of the load detector (6), (11u), (llv)
, (l1w) are U-phase, V-phase, and W-phase current detectors, (Iu), (Iv), respectively.

(Iw) are current detectors (11u) and (1
1v), the current detection signal detected by (l1w), (
13) A speed command generator that calculates a speed command according to the running of the car (2), (13a) is a speed command generator (13)
(14) is the subtracter, (15) is the speed control calculation circuit, (16) is the unbalanced load compensation circuit, (
17) is an adder, and (18) is a limiter, which outputs a predetermined value when the input is greater than a predetermined value, and otherwise outputs the input as is.

(19) is a coordinate conversion circuit that converts a three-phase input signal into an excitation component (Id) and a torque component (Iq), and (20) is a coordinate conversion circuit that converts a three-phase input signal into an excitation component (Id) and a torque component (Iq). (20a) is a magnetic flux calculation circuit that generates the signal (20a), (21) is a divider that divides the torque current (Iq) by the signal (20a), (ωS) is the slip frequency that is the output signal of the divider (21), and , (22) are the phase signals (22a), (22b) from the speed detection signal (5a) and the slip frequency (ωS).
This is a phase calculation circuit that calculates .

(23) is the magnetic flux command (Φr) and the magnetic flux detection signal (Φr)
(24) is a d-axis current command calculation circuit as an excitation component that calculates the excitation current command, (25)
is a limiter similar to the limiter (18), and outputs an excitation current command (Id). (26) and (27
) is a subtracter, (28) is a d-axis voltage command calculation circuit that issues a d-axis voltage command (Vd), (29) is a q-axis voltage command calculation circuit that issues a q-axis voltage command (Vq) as a torque component, ( 30) is the d-axis voltage command (Vd) and q
Axis voltage command (Vq) and three-phase voltage command (Vu
), (Vv), and (Vw).

Next, the operation of the conventional elevator control device configured as described above will be explained.

Now, in this elevator control device, the speed command (13a) calculated by the speed command generator (13) is compared with the speed detection signal (5a) by the subtractor (14),
Based on the deviation, a speed control calculation circuit (15) performs control calculations. This calculation result includes an unbalanced load compensation circuit (16) based on the load detection signal (6a) of the car (2).
) is added in an adder (17), and the torque current command (
Iq*).

In the coordinate conversion circuit (19), the three-phase current detection signal (Iu
), (Iv), and (Iw) are input, and the d-axis current (Id) and q-axis current (Iq) are determined based on vector control.

The magnetic flux calculation circuit (20) is configured as shown in FIG. 10, and the output signal (Φr) and the output signal (20a) of the coordinate conversion circuit (20) are expressed by the following equation.

0a- Id S+R2/ (M+12) S+R2/ (M+ lz) M+ 12 ld 1+ ((M+12)/R2)xSλd Here, R2 is the secondary resistance, M is the mutual inductance, 1
2 is the secondary inductance, and λd is the secondary magnetic flux. Furthermore, in the divider (21), ωS; Iq 0a Iq [1/ (S+R2/ (M+ t2 ))] I
d is calculated, and the phase calculation circuit (22) outputs the speed detection signal (5
a) and then integrated to calculate the phase angle θ and output phase signals (22a) and (22b). These phase signals (22a) and (22b) are respectively 22a: cosθ, cos(θ−2π/3),
cos(θ÷2z/3)22b: sinθ, 5
In(θ-2π/3), 5in(θ+2π/3).

The magnetic flux command (Φr) and the magnetic flux detection signal (Φr) are separated by a subtractor (
23) and sent to a d-axis current control calculation circuit (24) whose internal configuration is shown in FIG. 11, where a d-axis current command (Id) is obtained through a limiter (25).

The d-axis and q-axis current commands (Id*
), (Iq”) is the subtractor (26) or the subtractor (
27) d-axis current (Id) and q-axis current (Iq)
The d-axis voltage command calculation circuit (28) and the q-axis voltage command calculation circuit (29) perform control calculations to obtain a d-axis voltage command (Vd') and a q-axis voltage command (Vq). Then, this voltage command (Vd), (V
q) is converted into a three-phase voltage command (Vu) by the coordinate inverse transformation circuit (30).

(Vv) and (Vw), and controls the inverter (10) to rotate the induction motor (1).

That is, the following calculation is performed in the coordinate inverse transformation circuit (30).

In the above operation, when the elevator starts from a state where the elevator drive circuit is powered off, the magnetic flux command (Φr) is immediately set, but the magnetic flux detection signal (Φr)
is the time constant of induction motor (1) (M+12) /
Since there is a delay of R2 [sec], the deviation is amplified by the d-axis current command calculation circuit (24) and the d-axis current command (
Id) becomes as shown in FIG. This has the effect of accelerating the rise of magnetic flux.

On the other hand, in the unbalanced load compensation circuit (16), the load detection signal (
The unbalanced load is determined from 6a), and a torque current commensurate with the unbalanced load, that is, a q-axis current command (lq), is continued to be output so that a starting shock does not occur when the brake (not shown) is released. Here, the q-axis current command (1
The conversion to q) is as follows.

I q *= f d x Wu x D/2 x 1/, LX 1
/KG X 1/KL [A]K t -1/9.
8 XmX PxM2/(M+12)x I.

[Kg-c] However, Wu is unbalanced load, D is sheave diameter, and KL
is the roving ratio, KO is the gear ratio (sheave 50-ping,
gears are not shown), Kt is the torque constant, m is the number of phases (=3
), P is the number of pole pairs, and IO is the theoretical excitation current value (1/7 of the target value of Id).

[Problems to be Solved by the Invention] However, in the conventional elevator control device described above, at the time of startup, even though the d-axis current (Id) is larger than the target value, the exciting current (io) is target value)
/JN to calculate the q-axis current command (Iq), a torque larger than the actual unbalanced load compensation was generated.

SUMMARY OF THE INVENTION An object of the present invention is to provide an elevator control device that speeds up the build-up of magnetic flux and does not generate an unnecessarily large torque.

[Means for Solving the Problems] An elevator control device according to the present invention is an elevator control device that controls an induction motor for driving a car using a power conversion device whose voltage and frequency are variable. a coordinate conversion circuit that converts the three-phase primary current into a two-axis quantity of an excitation component and a torque component; an excitation current command calculation circuit that calculates a command value for the excitation component; and an excitation current command calculation circuit that calculates a command value for the torque component. It is composed of a torque current command calculation circuit and a correction circuit that corrects the torque current command using a coefficient inversely proportional to the excitation current command or the excitation component of the three-phase primary current.

[Function] In this invention, the magnitude of the excitation current command (d-axis current command) calculated by the excitation current command calculation circuit or the excitation component (d-axis current) of the three-phase primary current converted by the coordinate conversion circuit Since the conversion coefficient of the torque current command (q-axis current command) is determined in accordance with this, the rise of the magnetic flux is accelerated and the correct torque is output.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the main parts of an elevator control device according to an embodiment of the present invention, FIG. 2 is a block diagram showing the internal configuration of the q-axis current command conversion circuit, and FIG. 3 is a block diagram showing the internal configuration of the q-axis current command conversion circuit. FIG. 4 is a flowchart showing the operation of the current command conversion circuit, and a characteristic diagram showing the human power signal and output signal of the q-axis current command conversion circuit. Note that in the drawings, the same reference numerals and symbols as those in the conventional example in FIGS. Omitted.

In FIG. 1, (15a) is a speed control calculation circuit (15a).
) output horn signal, (16a) is the unbalanced load compensation circuit (1
6) is the output signal, (17a) is the output signal of the adder (17), (31) is the q-axis current command conversion circuit, and (31a) is the output signal of the adder (17).
) is its output signal.

In addition, Figures 2 and 3 show the q-axis current command conversion circuit (31
), where (32) is a conversion coefficient, (32a) is the multiplication result, and (33) is a divider that divides the multiplication result (32a) by the d-axis current command (Id). It is.

Next, the operation of the elevator control device of this embodiment configured as described above will be explained.

In the elevator control device of this embodiment, when a start command is issued, the d-axis current command (Id) rises at the same time as the start command, as shown in FIG.

On the other hand, the output signal (15a) of the speed control calculation circuit (15)
Even if the startup command is given manually, the speed command for startup (
It becomes zero until the time point (Ts) when 13a) occurs, and thereafter it rises depending on the deviation from the speed detection signal (5a). In addition, the output signal from the unbalanced load compensation circuit (16) (
16a) rises in a stepwise manner to the compensation value for the unbalanced load bone along with the activation command. Then, the speed control calculation circuit (1
5) output signal (15a) and the unbalanced load compensation circuit (16
) is the addition result of the output signal (16a) from the signal (
17a) is the transformation coefficient (32), i.e.
= (target value of Id) and further divided by the d-axis current command value (Id) to obtain a torque current command (Iq) as shown in FIG.

In other words, (Iq) = (Iq)
o) Id) However, (Iq)' is a q-axis current command value (Iq) that is inversely proportional to the d-axis current command (Id), which is calculated using the conventional q-axis current command value.

Note that (Iq) is the conventional q-axis current command value.

As a result, conventional τ　■　I.

However, Io is l/JT of the target value of (Id).

Further, τ is torque.

is r oc IoX(Id )/Io=(Id
), and the d-axis current command (I
It is possible to generate a torque (τ) proportional to d).

As described above, the elevator control device of the above embodiment includes a power conversion circuit that performs voltage variable control and frequency variable control (VVVF control) of the induction motor (1) for driving the elevator car, and A coordinate conversion circuit (19) that converts the three-phase primary current into two-axis quantities of an excitation component (Id) and a torque component (Iq), and a command value (Id) of the excitation component.
); a torque current command calculation circuit (15) that calculates the command value (Iq) of the torque component;
) and a qIdI current command conversion circuit (31) as a correction circuit that corrects the torque current command (Iq) by a coefficient (32) inversely proportional to the torque current command (Iq).

Therefore, the conversion coefficients (32) and (36) of the torque current command (Iq) are determined according to the magnitude of the excitation current command (Id) calculated by the excitation current command calculation circuit (24), and the magnetic flux rise It is possible to accelerate the increase and output the correct torque.

[Other Embodiments] Next, other embodiments shown in FIGS. 5 to 7 will be described.

FIG. 5 is a block diagram showing the main parts of an elevator control device according to another embodiment of the present invention, FIG. 6 is a block diagram showing the internal configuration of an unbalanced load compensation circuit, and FIG. 7 is a block diagram showing the unbalanced load compensation circuit. 3 is a flowchart showing the operation of the circuit. In the drawings, the same reference numerals and symbols as those in the conventional example shown in FIGS. 8 and 12 indicate the same or corresponding parts as those in the conventional example described above.

In the figure, (34) is a bias value, (35) is a subtracter, and (35a) is its output signal. (36) is a coefficient Kw, (36a) is the multiplication result thereof, and (37) is a divider that divides the multiplication result (36a) by the d-axis current command (Id).

Therefore, the operation of the elevator control device of this embodiment will be explained.

Now, as is clear from Fig. 4, dlTo current command (
Id ) differs significantly from the target value only at the beginning of activation. At this point, the speed control calculation circuit (15
Since the output signal (15a) of ) is zero, there is no problem even if the correction of the q-axis current command (Iq) by the d-axis current command (Id) is limited to the unbalanced load compensation.

The unbalanced load (Wu) corresponds to the output signal (35a) of the subtracter (35) in FIG. 6, and the coefficient (Kw) is Kw=D/2.
xl/KL xi/KG x9.8 XL/mxl/Px (M+12)/M
2, and by dividing it by the d-axis load/flow command (Id*) in the divider (37), it becomes 16a=WuxKw/Id'', and the conventional target value fTio is divided by the actual command (Id*).
d''), it can be seen that the same effect as in the above embodiment can be obtained.

In each of the above embodiments, the d-axis current command (Id) is used as the change gain setting condition for the q-axis current command (Iq).
), but the actual d-axis current (Id) may also be used.

[Effects of the Invention] As described above, the elevator control device of the present invention is an elevator control device that controls an induction motor for driving a car using a power conversion device whose voltage and frequency are variable. a coordinate conversion circuit that converts the negative order current of the three sums into a two-axis quantity of an excitation component and a torque component, an excitation current command calculation circuit that calculates a command value of the excitation component, and a command value of the torque component. and a correction circuit that corrects the torque current command by a coefficient inversely proportional to the excitation current command or the excitation component of the three-phase primary current. In addition to speeding up the process, it is possible to output the correct torque as required without generating an unnecessarily large torque.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the main parts of an elevator control device according to an embodiment of the present invention, FIG. 2 is a block diagram showing the internal configuration of the q-axis current command conversion circuit, and FIG. 3 is a block diagram showing the internal configuration of the q-axis current command conversion circuit. FIG. 4 is a flowchart showing the operation of the current command conversion circuit, FIG. 4 is a characteristic diagram showing the human power signal and output signal of the q-axis current command conversion circuit, and FIG. FIG. 6 is a block diagram showing the internal configuration of the unbalanced load compensation circuit, FIG. 7 is a flowchart showing the operation of the unbalanced load compensation circuit, and FIG. 8 is a diagram showing the conventional elevator control device. 9 is a block diagram showing details of the elevator control device in FIG. 8, and FIG. 10 is a block diagram showing the internal structure of the magnetic flux calculation circuit of the elevator control device in FIG. 9. The block diagram shown in FIG. 11 is also d
Block diagram showing the internal configuration of the shaft current command calculation circuit, 1st
FIG. 2 is a characteristic diagram showing the excitation current command output from the d-axis current command calculation circuit. In the figure, 1: induction motor 2: cage 15: speed control calculation circuit 16: unbalanced load compensation circuit 19: coordinate conversion circuit 24: d-axis current command calculation circuit 31: q-axis current command conversion circuit 32: conversion coefficient Id: Excitation component Iq: Torque component Id*: Excitation current command*. IQ is the torque current command. In the drawings, the same reference numerals and the same symbols indicate the same or equivalent parts. Agent Patent attorney: 1 Yu Odai, 2 others Fig. 8 1: Induction motorized stem 2: Car Fig. 11 φr H Royal procedure amendment (voluntary) 5° Subject to amendment Detailed Description of the Invention Column 6゜Amendment Contents 1, Indication of the Case 2, 7th line from the bottom of page 10 of the specification of Japanese Patent Application No. 1-33011, the name of the invention "(M+I2") is changed to elevator control The device makes the correction as [CM+Q2]. 3. Person making the correction

Claims (1)

[Claims] (1) A power conversion circuit that performs voltage variable control and frequency variable control of an induction motor for driving an elevator car, and coordinate conversion that converts the three-phase primary current of the induction motor into two-axis quantities of an excitation component and a torque component. an excitation current command calculation circuit that calculates a command value of the excitation component; a torque current command calculation circuit that calculates a command value of the torque component; and an excitation current command calculation circuit that calculates a command value of the torque component; An elevator control device comprising: a correction circuit that corrects the torque current command using an inversely proportional coefficient.