JPH059353B2 - - Google Patents

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 an elevator hoisting motor.

[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 were previously used exclusively from the viewpoint of control performance. Summer.

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 primary voltage 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 limit to control performance.

Therefore, we have improved control performance, and even reduced power consumption.
Various control devices configured to perform variable voltage/variable frequency control have been proposed as control devices for AC elevators that can save power. An example of a control means for realizing such a control device is a sine wave PWM control means using a voltage source inverter that controls the primary winding current of an induction motor in a sine wave shape, or controlling an induction motor like a DC motor. There are vector control means etc. that make this possible. By applying these control means to an elevator control device, not only excellent control performance can be obtained, but also a comfortable ride can be obtained.

FIG. 5 is a block diagram showing an example of the configuration of an AC elevator control device using the above-mentioned vector control and variable voltage/variable frequency control. Fifth
In the figure, 1 is an induction motor used as a hoisting motor for driving an elevator, and 2 is a variable voltage/variable frequency control device that controls the variable voltage and variable frequency of the induction motor 1. 3
is 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 command value signals 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. The car 5 and the counterweight 6 are connected via the sheave 4 to a main rope 7. 8 is a brake for braking the rotation of the sheave 4, and 9 is a brake device for releasing this brake 8.

On the other hand, 10 is an elevator speed command signal 10a
11 is a speed detector that detects the speed of the elevator and outputs a speed signal 11a; 12 is a speed control command signal 12a according to the deviation between the speed command signal 10a and the speed signal 11a;
This is a speed control calculation device that outputs. 13 is a load detector installed in the car 5 of the elevator to detect its load; 14 is an unbalanced torque command generator that generates an unbalanced torque command signal 14a in response to the load signal 13a from the load detector 13; 15 is an adding device that adds this unbalanced torque command signal 14a and the speed control command signal 12a and 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 device that generates a magnetic flux component current command signal 16a for determining the magnitude of the secondary magnetic flux from this magnetic flux component current command signal 16a; This is a magnetic flux establishment detection device that detects and generates a magnetic flux establishment signal 17a.

Reference numeral 18 inputs various elevator operation signals 18A, such as elevator call signals, for starting control of the induction motor 1, and issues control start commands to each of the above-mentioned devices 2, 9, 10, 12, 15, and 16. This is a driving operation command device that outputs signals 18a to 18f. When this driving operation command device 18 is given a control command from the outside, it starts excitation control according to the command from the magnetic flux component current command generation device 16, and uses the magnetic flux establishment detection device 17 to control the secondary After it is detected that the magnetic flux has been established, the adding device 15 is operated to perform torque control using the torque component current command signal 15a, and a brake release command is given to the brake device 9 to increase the speed after the brake 8 is released. It is designed to give driving operation commands to operate the command generation device 10 and the speed control calculation device 12.

Next, the operation of the AC elevator control device 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., this operation command device 18 outputs the variable voltage/variable frequency control device 2 and the magnetic flux component current command. Excitation control start command signals 18a and 18f that command the generator 16 to start excitation control are output. Therefore, the magnetic flux component current command generation device 16 operates the vector control calculation device 3 and the magnetic flux establishment detection device 17 in response to the excitation control start command signal 18f.
A magnetic flux component current command signal 16a is output to. The vector control calculation device 3 performs a predetermined vector control calculation based on the magnetic flux component current command signal 16a, and outputs a command value signal 3a indicating the amplitude command value I1 and frequency command value ω of the primary current of the induction motor 1. . Here, the vector control calculation is performed as follows. In other words, the amplitude command value I1 is the magnetic flux component current command value from the magnetic flux component current command generator 16.
Id, torque component current command value from addition device 15
If Iq, it is expressed as I1=√ ² + ² ...(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. Also, the above slip frequency ωs is calculated as follows, assuming that the secondary resistance of the induction motor 1 is R2 and the secondary inductance is L2, ωs = (Iq/Id) (R2/L2) × {1+(L2/R2)S}... (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 when the elevator is stopped, that is, Iq=0, ωr=0, I1=Id, ω=
It will be controlled by 0.

Then, by starting the excitation control, the induction motor 1
The secondary magnetic flux Φ2 responds to the magnetic flux component current command value Id by the following equation.

Φ2=[L2/1+(L2/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 establishes the secondary magnetic flux Φ2. After detecting, the magnetic flux establishment detection signal 17a is output to the driving operation command device 18.

FIG. 6 is a block diagram showing a specific example of the configuration of the magnetic flux establishment detection device 17 for realizing the calculation for detecting the establishment of the secondary magnetic flux Φ2.
In Figure 6, 21 is an operational amplifier, 22 is a resistor with a resistance value of "1/L2", and 23 is a resistance value of "1".
24 is a capacitor with a capacitance of "L2/R2", 25 is a secondary magnetic flux Φ2 setting device, and 26 is the output signal of the operational amplifier 21 and the secondary magnetic flux Φ2 set by the setting device 25. When the output signal reaches the set value, the magnetic flux establishment detection signal 17
This is a comparator that outputs a. In addition, the magnetic flux Φ2 has a secondary time constant T2= for the magnetic flux component current command value Id.
The motor starts up with a delay of L2/R2, but this secondary time constant T2 differs depending on the motor. However, the above secondary time constant T2 is the set value or the attenuation of the induced voltage,
That is, an outline can be obtained from the attenuation of the motor terminal voltage when the motor is kept rotating in a controlled state and the 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 addition device 15 receives the command value Iqw from the unbalanced torque command generator 14 and the command value from the speed control calculation device 12.
Iqo is added to find the torque component current command value Iq,
A torque component current command signal 15a is output to the vector control calculation device 3. However, since speed control has not been started in this state, the torque component current command value Iq becomes equal to the unbalanced torque command value Iqw.

In the vector control calculation device 3, when the torque component current command signal 15a is given, the
The amplitude command value I1 and the frequency command value ω of the primary current are determined based on equations (1) to (3). In this case, the induction motor 1 is in a stopped state, so equation (2) is ω=ωs
becomes. That is, when an unbalanced torque command is given, the primary current frequency is controlled by the slip frequency.

On the other hand, the generated torque τ, the torque component current I1q flowing in the primary winding of the induction motor 1, and the secondary magnetic flux Φ2
There is the following relationship: τ=(M/L2)I1q・Φ2...(5) That is, in a state where the secondary magnetic flux Φ2 is established, the torque is proportional to the torque component current I1q. Therefore, the torque component current command value Iq
The torque component current I1q is controlled by , and torque is generated. Generally, the current control response speed is very fast, so when unbalanced torque control is started, the torque reaches the target value immediately.

FIG. 7 shows the characteristics of the unbalanced torque command value Iqw. This unbalanced torque command value Iqw
is an example when the loading capacity is such that the car 5 and the counterweight 6 are exactly balanced, and depending on the unbalanced state of the car 5 and the counterweight 6, the characteristics shown in Fig. 7 are obtained. Become.

After the driving operation command device 18 generates an unbalanced torque generation command, it 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 the same as the unbalanced torque control command. do not have.

After confirming that the brake 8 has been released by the brake release command, the driving operation command device 18 outputs a speed control start command to the speed command generation device 10 and the speed control calculation device 12 as signals 18c and 18d. Although not shown, confirmation means for brake release may be implemented by a device that generates a signal when the brake operation time after a brake release command has elapsed, or by the operation of a limit switch capable of detecting 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 a speed control start command. Then, in the speed control calculation device 12,
A torque command value Iqo for tracking the speed is calculated according to the deviation between the speed command signal 10a and the speed signal 11a from the speed detector 11, and a speed control command signal 12a is output to the adding device 15. . As a result, as described above, the torque component current command value Iq is obtained in the adding device 15, and the amplitude command value I1 and frequency command value ω of the primary current are determined in the vector control calculation device 3. The variable frequency control device 2 controls the variable voltage of the induction motor 1.
Variable frequency is controlled.

As described above, in the control device of this configuration example, when a control start signal is given to the speed control device portion of the elevator, excitation current control is first started. Thereafter, when establishment of the secondary magnetic flux is detected by a device that simulates the secondary magnetic flux, unbalanced torque control, which is control unique to elevators, is started, and a brake release command is given. Then, when the release of the brake is confirmed, 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 begins after the brake is released, resulting in a smooth start and a comfortable ride. You can feel good.

From the above explanation, in an AC elevator with variable voltage/variable frequency control using vector control, it is necessary to properly establish the secondary magnetic flux Φ2 of the induction motor 1 in order to perform proper torque control and speed control.
This turns out to be an important point. In particular, unbalanced torque control at the time of starting the elevator has a significant effect on the ride comfort of the elevator. However, in the AC elevator control device as described above, when the simulated magnetic flux reaches a predetermined value, it is regarded as the establishment of the secondary magnetic flux, so if torque control is started in this state, the actual induction motor 1 Since the elevator is in an over-excited state, a torque exceeding an appropriate value is generated relative to the unbalanced torque command value, resulting in problems such as protrusion and drop-off when the elevator is started.

[Object of the Invention] The present invention has been made to solve the above-mentioned problems, and its purpose is to properly control the unbalanced torque when starting an elevator, thereby eliminating protrusion and running out of the elevator, thereby improving comfort. An object of the present invention is to provide a control device for an AC elevator that can provide a comfortable ride.

[Summary of the Invention] In order to achieve the above object, the present invention provides a magnetic flux component current command generation device that commands a magnetic flux component current value of an induction motor that drives an AC elevator, and a command signal from the magnetic flux component current command generation device. a magnetic flux establishment detection device that directly or indirectly detects the state of the secondary magnetic flux of the induction motor regardless of the presence or absence of the secondary magnetic flux, and detects the establishment of the secondary magnetic flux based on the detection signal; and a speed command for the AC elevator. a speed command generator that generates a speed command, a speed detector that detects the speed of the AC elevator, and a speed control torque that is determined according to the deviation between the detected value from the speed detector and the speed command value from the speed command generator. A speed control calculation device that outputs a command signal, a load detector that detects the load of the car of the AC elevator, and an unbalanced torque command that outputs an unbalanced torque command signal according to the detected value from the load detector. a generator; and an adding device that adds the unbalanced torque command signal output from the unbalanced torque command generator and the speed control torque command signal output from the speed control calculation device to output a torque component current command signal. The amplitude and frequency of the primary current of the induction motor are based on the torque component current command signal from the adding device, the magnetic flux component current command signal from the magnetic flux component current command generator, and the detected value from the speed detector. a vector control arithmetic device that commands the above; a variable voltage/variable frequency control device that controls the variable voltage and variable frequency of the induction motor based on the commands from the vector control arithmetic device; and a variable voltage/variable frequency control device that controls the brake of the AC elevator. When the brake device receives a control command from the outside, excitation control is started according to the command from the magnetic flux component current command generator, and the magnetic flux establishment detection device detects that the secondary magnetic flux of the induction motor has been established. Later, the adding device is operated to perform torque control using the torque component current command signal, 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. By being equipped with a driving operation command device that gives driving operation commands, the state of the secondary magnetic flux of the induction motor is constantly monitored regardless of whether the AC elevator is running or stopping, and unbalanced torque control is performed when starting the elevator. It is characterized by ensuring that it is carried out properly.

[Embodiment of the Invention] Hereinafter, an embodiment of the present invention shown in the drawings will be described. FIG. 1 shows in block form an example of the main part configuration related to magnetic flux establishment detection in an AC elevator control device according to the present invention, and the same parts as in FIGS. 5 and 6 are designated by the same reference numerals. The explanation will be omitted and only the different parts will be described here.

In the figure, 16 is a magnetic flux component current command generator which receives the excitation current control command signal 18f shown in FIG. A magnetic flux establishment detection device 27 receives the current command signal 16a and is composed of a secondary magnetic flux Φ2 simulation section and a secondary magnetic flux Φ2 establishment detection section as shown in FIG.
A first AND operation circuit performs an AND operation of the magnetic flux establishment detection signal 17a from the magnetic flux establishment detection signal 17a and the excitation current control command signal 18f, and 28 is an output signal 27a from the first AND operation circuit 27 and a command (not shown). This is a second AND operation circuit that performs an AND operation with the torque control start command signal 18g from the circuit, and outputs its output signal as a signal corresponding to the signal 18e shown in FIG.

FIG. 2 shows the magnetic flux component current command generator 16.
FIG. 2 is a circuit diagram showing an example of the configuration. In FIG. 2, 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, 54, 55, 56 is a resistor with a resistance value of "1", and 57 is a capacitor with a capacitance of "C" provided to avoid a sudden change in the magnetic flux command. Further, 17aa and 18fa are the magnetic flux establishment detection signal 17a and the exciting current control command signal 1.
These are contacts that respond to 8f, respectively, and each setter 5 above.
1 and 52 and each resistor 54 and 55 as shown in the figure.

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

Now, when the exciting current control command signal 18f is given, the magnetic flux component current command generating device 16 selects the forcing current value given by the second setter 52 since the magnetic flux establishment detection signal 17a is "0". As a result, the secondary magnetic flux Φ2 simulation section of the magnetic flux establishment detection device 17 receives the above-mentioned forcing current signal 16a and simulates the secondary magnetic flux Φ2. Then, when this simulation value Φ2s exceeds the setting value of the setting device 25 shown in FIG. The selection is changed from the setting device 52 to the first setting device 51, and the magnetic flux component current rated value is output. Due to this action, the secondary magnetic flux Φ2
is set to the rated value, and the simulation value Φ2s is also held constant. On the other hand, the first AND operation circuit 27 outputs a "1" signal since both the excitation current control command signal 18f and the magnetic flux establishment detection signal 17a are "1". In this state, a torque control start command signal 1 is sent from a command circuit (not shown).
When 8g becomes “1”, the second AND operation circuit 2
8 becomes "1".

The elevator stops and excitation current control command signal 1
When 8f becomes "0", the output signal 16a of the magnetic flux component current command generator 16 becomes zero, and as a result, the simulation value Φ2s of the secondary magnetic flux Φ2 simulation section also decreases, and when this falls below the setting value of the setting device 25, the magnetic flux decreases. The establishment detection signal 17a also becomes "0". However, the output of the first AND operation circuit 27 becomes "0" immediately when the excitation current control command signal 18f becomes "0".

In this case, the simulation value Φ2s of the secondary magnetic flux Φ2 operates independently of the output signal 16a from the magnetic flux component current command generator 16, and is not set even after the excitation current control command signal 18f becomes "0". It attenuates with a first-order lag according to the motor secondary time constant T2=L2/LR, and if the setting of this time constant T2 is appropriate, it coincides with the attenuation of the secondary magnetic flux Φ2 of the induction motor 1. If the elevator remains stopped for a long time, the motor secondary magnetic flux Φ2 becomes zero and control is performed again using the above operation. However, if the elevator remains stopped for a short time, the control starts from a state where it does not decay to zero. will be started. In this case as well, since the simulation value Φ2s of the secondary magnetic flux Φ2 continues to operate regardless of the output signal 16a from the magnetic flux component current command generator 16 as described above, the secondary magnetic flux Φ2 of the induction motor 1 The simulation will be started from a value in the middle of decay in synchronization.

FIG. 3 shows the state of each signal when excitation current control is started again in the middle of attenuation of the secondary magnetic flux Φ2. In the figure, the excitation current command signal 16a
(Id) becomes zero and the secondary magnetic flux Φ2 attenuates with a time constant T2. Further, the magnetic flux establishment detection signal 17a becomes "0", and when the excitation current control command signal 18f becomes "1" again after attenuating to a certain value, Id is given by a forcing value and the secondary magnetic flux Φ2s rises steeply. . Further, when the secondary magnetic flux Φ2s exceeds the set value of the setting device 25, the magnetic flux establishment detection signal 17a becomes "1", and Id becomes the rated value, and the secondary magnetic flux Φ2s is maintained at a constant value. In this case, the secondary magnetic flux Φ2 of the induction motor 1 and the simulation value Φ2s are the secondary time constant T2
If is correct, they will always match.

FIG. 4 shows a case where the secondary magnetic flux simulation is not performed continuously, for example, a case where it is cleared after every operation. In the figure, when the excitation current control command signal 18f becomes "1" again and the simulation value Φ2s reaches the setting value of the setting device 25 and forcing is canceled, the secondary magnetic flux Φ2 of the induction motor 1 increases by the residual amount. Then the time constant T2
Set to the rated value with .

From the above, the controller shown in FIG. 5 considers the secondary magnetic flux established when the simulated secondary magnetic flux Φ2s reaches a predetermined value, so if torque control is started in this state, the actual induction motor 1 Since the is in an over-excited state, it generates a torque higher than the appropriate value for the unbalanced torque command value, which caused the elevator to pop out or fall when starting. As described above, in the control device of the embodiment, the simulation of the secondary magnetic flux is configured to operate independently of the control command signal, so if the excitation current control command signal 18f is repeatedly turned on and off in a short period of time, In addition, the simulation value Φ2s always tracks in synchronization with the secondary magnetic flux Φ2 of the induction motor 1, so proper detection is possible, and the unbalanced torque control at the time of elevator startup is also performed properly, allowing the elevator to start smoothly. A comfortable ride can be obtained by eliminating protrusion and sagging.

It should be noted that the present invention is not limited to the embodiments described above, but can also be implemented in the following manner.

Although the hardware configuration has been described as an example in FIG. 1, the present invention is not limited to this, and can be easily realized by digital calculations and logical calculations using a microcomputer or the like.

Furthermore, by using a detector for detecting the secondary magnetic flux of the induction motor 1 in place of the secondary magnetic flux Φ2 simulation section shown in FIG. 6, the control accuracy of the present control device can be further improved. Needless to say, this is possible.

In addition, the present invention can be modified and implemented in various ways without changing the gist thereof.

[Effects of the Invention] As explained above, according to the present invention, in a control device that performs variable voltage/variable frequency control of an AC elevator using an induction motor by a vector control method, the control device is controlled by a magnetic flux component current command signal. Since the state of the secondary magnetic flux Φ2 of the induction motor is constantly monitored and established regardless of whether the elevator is started or stopped, unbalanced torque control at the time of elevator startup is properly performed to control the elevator from start to stop. It is possible to provide an extremely reliable control device for an AC elevator that can smoothly control up to 100 degrees and provide a comfortable ride by eliminating jumps and drop-offs.

[Brief explanation of the drawing]

FIG. 1 is a configuration block diagram showing one embodiment of the present invention, FIG. 2 is a circuit diagram showing details of a magnetic flux component current command generating device in the same embodiment, and FIGS.
5 is a time chart for explaining the operation of the same embodiment, FIG. 5 is a block diagram showing a conventional AC elevator control device, FIG. 6 is a circuit diagram showing the magnetic flux establishment detection device in FIG. 5, and FIG. FIG. 7 is a diagram showing the characteristics of the unbalanced torque command value. 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 generator, 11...
...Speed detector, 12...Speed control calculation device, 13
... Load detector, 14 ... Unbalanced torque command generation device, 15 ... Addition device, 16 ... Magnetic flux component current command generation device, 17 ... Magnetic flux establishment detection device, 17
aa...Contact, 18...Driving operation command device, 18
fa... Contact, 21, 53... Operational amplifier, 22,
23, 54, 55, 56...Resistor, 24, 57
... Capacitor, 25, 51, 52 ... Setting device,
26... Comparator, 27, 28... AND operation circuit.

Claims (1)

[Claims] 1. A magnetic flux component current command generation device that commands the magnetic flux component current value of an induction motor that drives an AC elevator, and a state of the secondary magnetic flux of the induction motor regardless of the presence or absence of a command signal from this magnetic flux component current command generation device. a magnetic flux establishment detection device that directly or indirectly detects the establishment of the secondary magnetic flux based on the detection signal; a speed command generation device that generates a speed command for the AC elevator; and a speed command generation device that generates a speed command for the AC elevator; a speed detector for detecting a speed; a speed control calculation device for outputting a speed control torque command signal according to a deviation between a detected value from the speed detector and a speed command value from the speed command generator; A load detector that detects the load of the car, an unbalanced torque command generator that outputs an unbalanced torque command signal according to the detected value from the load detector, and an unbalanced torque command generator that outputs an unbalanced torque command signal. an adding device that adds an unbalanced torque command signal and a speed control torque command signal output from the speed control calculation device to output a torque component current command signal; a torque component current command signal from the adding device and the magnetic flux; 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 a component current command generation device and a detected value from the speed detector, and this 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 commands from the AC elevator; a brake device that controls the brakes of the AC elevator; Excitation control is started based on the command from the magnetic flux component current command generator, and after the magnetic flux establishment detection device detects that the secondary magnetic flux of the induction motor has been established, the adding device is operated to generate the torque based on the torque component current command signal. and a driving operation command device that controls the brake device and gives a brake release command to the brake device, and after the brake is released, gives a driving operation command to operate the speed command generation device and the speed control calculation device. An AC elevator control device characterized by: