JPS6181375A - Controller for alternating current elevator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a control device for an AC elevator that uses an induction motor as a hoisting motor for the elevator.

[Technical background of the invention and its problems] In recent years, with the progress of power electronics and microelectronics, induction motors have come to be used in many fields where DC motors had previously been used exclusively from the viewpoint of control performance. Became.

In the field of elevators, AC elevators using induction motors have come into practical use in place of DC elevators using DC motors having separately excited field windings. However, the conventional control means for an AC elevator using an induction motor is a so-called -number position pressure control means that simply controls the magnitude of the primary winding voltage of the induction motor using a thyristor or the like. Therefore, there was a natural limit to control performance. Accordingly, various control devices configured to perform variable voltage/variable frequency control have been proposed as control devices for AC elevators that can improve control performance and achieve power saving and power saving equipment. An example of a control means for realizing the above control device is a sine wave PW MILJ 111 means using a voltage source inverter that controls the primary winding current of an induction motor in a sinusoidal manner, or a means for controlling the primary winding current of an induction motor in the form of a sine wave. There are vector control means and the like that enable control. By applying these control means to an elevator control device, not only excellent control performance can be obtained, but also a comfortable ride.

However, the AC elevator control device using the induction motor has the following problems. That is, the control device for an AC elevator is significantly different from the control device for a conventional DC elevator using a separately excited DC motor. For example, in a separately excited DC motor, the magnetic flux component is approximately proportional to the current in the field winding, so the state of the magnetic flux can be determined from the value of the field current, but in an induction motor, -
The state of the magnetic flux cannot be known unless both the magnetic flux component and the torque component are controlled using numerical flow. Therefore, it is necessary to perform appropriate control that matches the operating characteristics of the elevator.

Furthermore, as an operation control means specific to elevators, a control means is required to compensate for the unbalanced torque between the car and the counterweight at the start of the elevator. Because the magnetic flux component and torque component are controlled together, even if control is performed using an appropriate unbalanced torque command at the start of control, the secondary magnetic flux of the induction motor is determined by the secondary time constant determined by the resistance and inductance of the secondary winding. The magnitude of the generated torque may change during a transient state. For this reason, accurate torque may not be obtained immediately, and there is a risk that proper unbalanced torque control may not be performed even if the brake is released.

[Purpose of the invention]

An object of the present invention is to provide a control device for an AC elevator in which speed control including unbalanced torque control is performed smoothly and with high precision, control performance is improved, and a comfortable ride can be obtained.

[Summary of the invention]

In order to achieve the above object, the present invention is characterized by the following configuration. That is, when a control command is given from the outside, the magnetic flux component current command device commands the magnetic flux component current value of the AC elevator driving induction motor, and excitation control based on this command is started. After the magnetic flux establishment detection device detects that the secondary magnetic flux of the electric motor is established, the addition device is activated to command a torque component current based on the unbalanced torque command signal output from the unbalanced torque command device. A signal is obtained, and torque control is performed using this torque component current command signal, and a brake release command is given to the brake device of the AC elevator, and after the brake is released, the speed command generation device and the speed calculation device are activated to issue a speed control torque command. The present invention is characterized in that a signal is supplied to the adding device.

[Embodiments of the invention]

FIG. 1 is a block diagram showing the configuration of a first embodiment of the present invention. In FIG. 1, reference numeral 1 is an induction motor used as a hoisting motor for driving an elevator, and reference numeral 2 is a variable voltage/variable frequency control device that controls the variable voltage and variable frequency of the induction motor 1. Reference numeral 3 denotes a vector control calculation device that calculates command values for the amplitude and frequency of the primary current of the induction motor 1 and outputs a command value signal 3a to the variable voltage/variable frequency control device 2. 4 is a sheave of an elevator hoisting machine, 5 is a car of the elevator, and 6 is a counterweight, and the car 5 and the counterweight 6 are connected via the sheave 4 by a main rope 7. 8 is a brake for braking the rotation of the sheave 4, and 9 is a brake device for releasing the brake 8. 10 is a speed command generator that generates a speed command signal 10a for the elevator, 11 is a speed detector that detects the speed of the elevator and outputs a speed signal 11a, and 12 is a device that responds to the deviation between the speed command signal 10a and the speed signal 11a. This is a speed control calculation device that outputs a speed control command signal 12a. 13 is a load detector provided in the car 5;
4 is an unbalanced torque command generating device that generates an unbalanced torque command signal 14a according to the load signal 13a from the load detector 13; 15 is the sum of the unbalanced torque command signal 14a and the speed control command signal 12a; This is an adding device that outputs a torque component current command signal 15a. 16 is a magnetic flux component current command generating device that generates a magnetic flux component current command signal 16a for controlling the magnitude of the magnetic flux component of the induction motor 1; 17 is a magnitude of the secondary magnetic flux from the magnetic flux component current command value @16a; This is a magnetic flux establishment detection device that detects the magnetic flux establishment signal 17a and generates a magnetic flux establishment signal 17a. 18 inputs various elevator operation signals 18Δ for starting control of the induction motor 1, such as elevator call signals, etc., and sends control start command signals to each of the devices 2.9, 10.12.15.16. This is a driving operation command device that outputs signals 18a to 18f. When this driving operation command device 18 receives a control command from the outside, it starts excitation control according to the command from the magnetic flux component current command device, and detects that the secondary magnetic flux of the induction motor has been established by the magnetic flux detection device. After the detection, the addition device is operated to perform torque control based on the torque component current command, and a brake release command is given to the brake device, and after the brake is released, the speed command generation device and the speed control calculation device are operated. It is designed to give driving operation commands as required.

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

Now, when an excitation control start command is given to the operation command device 18 as an elevator operation signal 18A from a part that calls the elevator, etc., the operation command device 18 sends a command to the variable voltage/variable frequency control device 2 and the magnetic flux component current command. Outputs υj1[l start command signals 18a and 18f that command the generator 16 to start excitation control. Therefore, the magnetic flux component current command generator 16 generates an excitation control start command signal 1.
8f, a magnetic flux component current command signal 16a is output to the vector control calculation device 3 and the magnetic flux establishment detection device 17.

The vector control arithmetic device 3 has a magnetic flux component current command signal 1
A predetermined vector control calculation is performed based on 6a, and a command value signal 3a indicating the amplitude command value 1 and frequency command value ω of the primary current of the induction motor 1 is output. The above vector control calculation is performed as follows.

The amplitude command value ■1 is 11=+, where Id is the magnetic flux component current command value from the magnetic flux component current command generator 16, and Iq is the torque component current command value from the adding device 15.
q ・Represented by (1). On the other hand, the frequency command value ω is expressed as ω=ωS+ωr (2), where ωS is the slip frequency and ωr is the rotational frequency of the induction motor 1. Further, the above slip frequency ωS is calculated by ωs= (Ia/Id)(R2/L2') x (1+ (
L2/R2>8)...Represented by (3). Note that in equation (3), S is a differential operator.

Therefore, as is clear from equations (1) to (3) above,
When excitation control is started in the elevator stopped state, that is, I(]=O, ωr=0, 11=Id.

It will be controlled at ω=0.

Next, with the start of excitation control, the secondary magnetic flux Φ2 of the induction motor 1 responds to the magnetic flux component current command value 1d by the following equation.

Φ2= [L2/(1+ (12/R2)S)] Id
(4) On the other hand, the magnetic flux establishment detection device 17 calculates the secondary magnetic flux Φ2 based on the above equation (4), and after detecting the establishment of the secondary magnetic flux 2, transmits the magnetic flux to the driving operation command device 18. Establishment detection signal 17a
Output.

FIG. 2 is a block diagram showing a specific configuration of the magnetic flux establishment detection device 17 for realizing the calculation for detecting the establishment of the secondary magnetic flux Φ2. In FIG. 2, 21 is an operational amplifier;
22 is a resistor with a resistance value of rl/L2j, 23 is a resistor with a resistance value of "1", 24 is a capacitor with a capacitance of rL2/R2J, 25 is a setting device for secondary magnetic flux Φ2, 26 is the above calculation This comparator compares the output signal of the amplifier 21 with the set value of the secondary magnetic flux Φ2 set by the setter 25, and outputs the magnetic flux establishment detection signal 17a when the output signal reaches the set value. Note that the secondary magnetic flux Φ2 rises with a delay of a secondary time constant 72=12/R2 with respect to the magnetic flux component current command value 1d, but this secondary time constant T2 differs depending on the motor. However, the above-mentioned secondary time constant T2 is a design value or attenuation of the induced voltage, that is, when the motor is rotated in a controlled state,
An outline can be obtained from the attenuation of the motor terminal voltage when control is stopped.

The driving operation command device 18 to which the magnetic flux establishment detection signal 17a is input outputs a control start command signal 18a to the adding device 15. Then, the adding device 15 adds the command value IQW from the unbalanced torque command generating device 14 and the command value IqO from the speed control calculation device 12 to obtain the torque component current command value IQ, A torque component current command signal 15a is output to. However, since speed control has not been started in this state, the torque current component command value Iq becomes equal to the unbalance 1 to the torque command value 1qw.

In the vector control calculation device 3, when the torque component current command signal 15a is given, the above-mentioned (1) to (3) are executed.
An amplitude command value 11 and a frequency command value ω of the primary current are determined based on the formula. In this case, since the induction motor 1 is in a stopped state, (Equation 21 becomes ω = ωS. In other words, when an unbalanced torque control command is given, the -number positional current frequency is controlled by the slip frequency. .

On the other hand, the generated torque τ, the torque component current 11Q flowing through the primary winding of the induction motor 1, and the secondary magnetic flux Φ2 are expressed as τ= (M/L2)11Q・Φ2 (5
) There is a relationship. That is, in a state where the secondary magnetic flux Φ2 is established, the torque is proportional to the torque component current 11Q. Therefore, the torque component current 11q is controlled by the torque component current command value Iq, and torque is generated. Generally, the current control response speed is very slow, so when unbalanced torque control is started, the torque reaches the target value immediately.

FIG. 3 is a diagram showing the characteristics of the unbalanced torque command value IQW. The unbalanced torque command value IQW becomes zero when the loading amount is such that the car 5 and the counterweight 6 are exactly balanced, and the unbalanced torque command value IQW becomes zero depending on the unbalanced state of the car 5 and the counterweight 6. The characteristics are as shown in Figure 3.

After generating an unbalanced torque generation command, the driving operation command device 18 outputs a brake release command to the brake device 9 as a control start signal 18b. Here, when the magnetic flux is established, torque is generated very quickly, so there is no problem in practice even if the brake release command is generated almost simultaneously with the unbalanced torque control command.

After confirming that the brake 8 has been released by the brake release command, the driving operation command device 18 transmits the speed command generation device 1.
0 and the speed control calculation device 12 ([Outputs the speed control start command as signals 18c and 18d. Although not shown, the brake release confirmation means generates a signal when the brake operation time after the brake release command has elapsed. This can be done by operating a device that detects brake release or a limit switch that can detect brake release.

The speed command generation device 10 outputs a speed command signal 10a according to the operation mode of the elevator to the speed control calculation device 12 in response to the speed control start command.

Then, in the speed control calculation device 12, the speed command signal 10a and the speed signal 11a from the speed detector 11 are combined.
A torque command value IQO for causing the speed to follow the torque is calculated according to the deviation from the torque, and a speed control command signal 12a is output to the adding device 15. As a result, as described above, the torque current component command value Tq is obtained in the adding device 15, and the amplitude command value 11 and frequency command value ω of the primary current are determined in the vector control calculation device 3, and then the variable voltage A variable frequency control device 2 controls the variable voltage and variable frequency of the induction motor 1.

Note that the driving operation command device 18 that operates as described above is
This can be easily implemented using sequence circuits such as relays, logic sequence circuits, or software using a microcomputer.

Figure 4 is a flowchart 1 showing the flow of the driving operation described above.
It is ~.

As described above, in this embodiment, when a control start signal is given to the speed control device section of the elevator, excitation current control is first started. After that, when the establishment of secondary magnetic flux is detected by a device that simulates secondary magnetic flux, unbalanced torque control, which is a control unique to elevators, is started.
Furthermore, a brake release command is given. Then, when it is confirmed that the brake is released, speed control is started, and the elevator is operated at a desired speed based on the speed command.

Therefore, since torque control is performed after the magnetic flux is established, not only is unbalanced torque control reliable and accurate, but speed control is initiated after the brake is released, resulting in a smooth start and a comfortable ride. can get.

By the way, the rise of the secondary magnetic flux Φ2 is caused by the secondary time constant 12. /R2, so in the first embodiment, if the secondary time constant of the induction motor 1 is large, it takes a considerable amount of time to establish the magnetic flux.

Therefore, it may take a relatively long time until the elevator starts.

FIG. 5 shows a magnetic flux component current command generating device 16' in a second embodiment of the present invention configured to solve the above problems.
FIG. In FIG. 5, 51 is a first setting device for setting a rated magnetic flux component current value, 52 is a second setting device for setting a forcing current value higher than the rated value, 53 is an operational amplifier, and 54.55.56 are each with a resistance value of “1”
The resistor 57 is a capacitor with a capacitance of "C", which is installed to avoid a sudden change in the magnetic flux command. 58., 59 are the above-mentioned No. 1. The first setter 51,52 is used to select the signal output from the second setter 51,52. The first switch 58 is the second switch, and the excitation control start command 18a from the driving operation command device 18 and the magnetic flux establishment signal 17
When both a and a are given, it turns on and makes the rated current value the magnetic flux component current command value. On the other hand, the second switch 5
9 turns on when the excitation control start command 18a is given, and sets the forcing current value to the magnetic flux component current command value;
When the magnetic flux establishment signal 17a from the magnetic flux establishment detection device 17 is given, it turns off.

FIG. 6 is a diagram showing the rise of the magnetic flux component current command Td and the secondary Un flux Φ2 when forcing is not performed, which is the first embodiment, and FIG. Magnetic flux component current command 1d and secondary magnetic flux Φ when
FIG. 2 is a diagram showing the rise of No. 2; As is clear from the comparison between FIG. 6 and FIG. 7, according to the second embodiment, the magnetic flux establishment time is shortened from TN to Tp. Therefore, the elevator can be started quickly.

Note that the present invention is not limited to the above embodiments. For example, in the embodiment described above, the secondary magnetic flux Φ2 was determined by simulation as shown in FIG. 2, but a magnetic flux detection element may be installed in the motor body to directly detect the magnetic flux. Furthermore, since the secondary resistance R2 of the induction motor 1 changes depending on the temperature, the rise of the magnetic flux can be detected by detecting the temperature of the stator of the induction motor 1 and correcting the secondary time constant T2=12/R2. The accuracy may be increased, and the stability during speed control may be improved by using the correction value as the secondary resistance value of the vector control calculation device.

〔Effect of the invention〕

According to the present invention, when a control command is given from the outside,
A magnetic flux component current value of an induction motor for driving an AC elevator is commanded from a magnetic flux component current command device, and excitation control based on this command is started. After the magnetic flux establishment detection device detects that the secondary magnetic flux of the electric motor is established, the addition device is activated to command a torque component current based on the unbalanced torque command signal output from the unbalanced torque command device. A signal is obtained, and torque control is performed using this torque component current command signal, and a brake release command is given to the brake device of the AC elevator, and after the brake is released, the speed command generation device and the speed calculation device are activated to control the speed. - Since the torque command signal is given to the adding device, speed control including unbalanced torque control is performed smoothly and with high precision, improving control performance and providing a comfortable ride for AC elevator control. equipment can be provided.

[Brief explanation of drawings]

1 to 4 are diagrams showing a first embodiment of the present invention, in which FIG. 1 is a block diagram showing the configuration, FIG. 2 is a block diagram showing the specific configuration of the magnetic flux detection device, and FIG. Figure 4 is a characteristic diagram showing the output characteristics of the unbalanced torque command generating device, Figure 4 is a flowchart for explaining the operation, Figures 5 to 7 are diagrams showing the second embodiment of the present invention, and Figure 5 is a diagram showing the output characteristics of the unbalanced torque command generating device. 6 is a block diagram showing a specific configuration of the magnetic flux component current command generating device, and FIGS. 6 and 7 are waveform diagrams for explaining the operation and effect. DESCRIPTION OF SYMBOLS 1... Induction motor, 2... Variable voltage variable frequency control device, 3... Vector control calculation device, 5... Elevator car, 8... Brake, 9... Brake device, 10 ... Speed command generation device, 11 ... Speed detector, 12 ... Speed control calculation device, 13 ... Load detector, 14 ... Unbalanced torque command generation device, 15 ...
Adding device, 16... Magnetic flux component current command generating device, 17
...Magnetic flux posting device, 18...Driving operation command device. Applicant's Representative Patent Attorney Takehiko Suzue Figure 2 Figure 3 Figure 4 Start N. 1'' 14 six stone li sum 1111jf rate h h 1 arrow body inside l wholesale ゛ 1 N. 1 ■ 3 ' ・,・ No ■ Morusuffer1g single 1 Reiko
N sheep 1'M'. m D ゛ ” nqt Lee-r. Zu・shi sacrifice @′￥′t4/? - Ie Kame 9”o””. Zushi N. ES Renacid Soku 42 q) Clear

Claims (1)

[Claims] A magnetic flux component current command device that commands a magnetic flux component current value of an induction motor that drives an AC elevator, and a magnetic flux establishment detection that detects the establishment of a secondary magnetic flux of the induction motor based on a command signal from the magnetic flux component current command device. a speed command generating device that generates a speed command for the AC elevator;
a speed detector that detects the speed of the AC elevator; a speed control calculation device that outputs a speed control torque command signal according to a deviation between a detected value of the speed detector and a speed command value of the speed command generator; a load detector that detects the load of the elevator car; an unbalanced torque command generator that outputs an unbalanced torque command signal according to the detected value of the load detector; and an output from the unbalanced torque command generator. an adding device that outputs a torque component current command signal by adding the unbalanced torque command signal output from the speed control calculation device and the speed control torque command signal output from the speed control calculation device; a vector control calculation device that commands the amplitude and frequency of the primary current of the induction motor based on a magnetic flux component current command signal from the magnetic flux component current command device and a detected value from the speed detector; and the vector control calculation device. a variable voltage/variable frequency control device that controls the variable voltage and variable frequency of the induction motor based on a command from the device; a brake device that controls the brake of the AC elevator; and when a control command is given from the outside. Excitation control based on a command from the magnetic flux component current command device is started, and after the magnetic flux detection device detects that the secondary magnetic flux of the induction motor is established, the adding device is operated to perform torque control based on the torque component current command. and a driving operation command device that gives a brake release command to the brake device and gives a driving operation command to operate the speed command generating device and the speed control calculation device after the brake is released. Control equipment for AC elevators.