JPS60228380A - Controller for 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 converts direct current smoothed by a smoothing capacitor into variable frequency alternating current power and drives an alternating current motor with this alternating current power. be.

[Prior art]

Conventionally, in an elevator in which a conductive motor is driven by a variable frequency alternating current power source, alternating current is converted to direct current, this direct current is smoothed by a smoothing capacitor, and then converted to variable frequency alternating current by an inverter. In this type of elevator, if the quality of smoothing capacitors from various manufacturers decreases, the riding comfort deteriorates, so a device that detects the decline of smoothing capacitors from various manufacturers was published in Japanese Patent Laid-Open No. 58-15.
It was proposed in No. 4395.

FIG. 1 shows a conventional AC elevator control device.

In the figure, R, S, and T are three-phase AC power supplies, and (1) is a power switch that turns on or shuts off the AC power supplies R, S, and T.

(21 is a converter that is connected to the power switch +I+ and is composed of a thyristor and rectifies the power supply voltage into a DC voltage.

(3) is a smoothing capacitor connected to the DC side of the converter (2), and (4) is connected to the smoothing capacitor (3) and is composed of a transistor and a diode, converting DC power into AC power of any voltage and frequency. (5) is a control circuit that controls the converter (2) and invert (4); (61 is the inverter (4);
A three-phase induction motor for hoisting connected to the alternating current side of.

(7) is a drive sheave for the hoist driven by the electric motor (6).

(8) is the main rope wrapped around the sheave (7), +91
, [lG are the heel and counterweight respectively connected to both ends of the main rope (8). (lυ is a rectifier circuit connected to the power switch m and one end of the DC side is connected to one end of the smoothing capacitor (3), θ2 is a resistor connected to the other DC side of the rectifier circuit 11υ, 0 is a resistor (l ) is connected to the other end of the smoothing capacitor (3) and is closed for a certain period of time after the power switch (1) is turned on (circuit omitted).The electromagnetic contactor contact Q4) is connected to both ends of the smoothing capacitor (3). This is a charging time measuring circuit that measures the charging time of the connected smoothing capacitor (3) and sends an abnormal signal to the control circuit (5) in case of an abnormality. The device contact α and the charging time measuring circuit Oa are a detection means (100) for detecting a decrease in the capacitance of the smoothing capacitor (3).
It constitutes.

Next, the operation of this conventional example will be described.

In other words, three-phase AC power is converted to DC power by the converter (2) and smoothing capacitor (3), and then the inverter (
4) is given. The inverter (4) converts the applied DC power into variable voltage/variable frequency AC power and supplies it to the electric motor (6). These are controlled by a control circuit (5). The electric motor (6) is now driven,
The car (9) goes up and down.

On the other hand, when the power switch +11 is turned on, contact 0 is closed for a certain period of time (time until the smoothing capacitor (3) is charged). Now the smoothing capacitor (3) has a resistance Q
Charging starts through 2, and the charging current is:

It gradually increases according to a time constant determined by the capacitance of the smoothing capacitor (3) and the resistance value of the resistor 02. During this time.

The firing command to the thyristor of the converter (2) and the operation command to the inverter (4) are not generated from the control circuit (5).

On the other hand, the charging time measuring circuit I uses a smoothing capacitor (3)
Measure the charging time of and monitor this charging time.

If it is detected that the time is shorter than a predetermined time, an abnormality signal is generated. In response to this abnormal signal, the control circuit (5) reduces the output of the inverter (4) to zero to prevent the operation of the car (9), and replaces the smoothing capacitor (3) before the car (9) can no longer be serviced normally. That's what I'm trying to replace. However, when a power outage occurs, the result is the same as if the power switch tl+ was shut off. At this time, smoothing capacitor (3)
If the capacity of the car (9) has decreased, even if the power is restored, the operation of the car (9) will remain blocked. For this reason, there is a possibility that a passenger may be trapped in the car (9) for a long time.

[Summary of the invention]

This invention was made in view of the above drawbacks.

The purpose of this system is to prevent deterioration in elevator service by allowing the elevator to continue operating even if the smoothing capacitor is abnormal, and by notifying staff of the smoothing capacitor abnormality during inspection.

[Embodiments of the invention]

FIGS. 2 and 3 show an embodiment of the present invention.

In the figure, (G) and (F) are control power supplies, (13a) is a normally open contact that closes for a certain period of time after the power switch ill is turned on, and (14a) is a photoelectric time measurement circuit α chrysanthemum that detects an abnormal signal. (21A) - is a normally open contact that is closed during automatic operation; (21B) is a normally open contact that is closed during manual operation (operation performed during elevator maintenance); 21Ba) is a normally closed contact that is also opened.

(To) is an operation mode check relay that identifies whether automatic operation is manual operation. One end is a normally closed contact (2ip), and the control power is supplied through a series circuit of a normally open contact (21A) and a normally open contact (13a). ), and the other end is connected to the control power supply (to). (2Da) and (20b) are the normally open contacts of the operation mode check relay wire, respectively, and the switch is the operation prevention contactor that enables the elevator to operate in the energized state and prevents the elevator from operating in the deenergized state. Closed contact (14a).

It is connected to a control power source (E) through a parallel circuit consisting of normally open contacts (20b) and (21B), and the other end is connected to a control power source (C). (22a) is a normally open contact consisting of three poles of the operation prevention contactor (Corporation Co., Ltd.), which is connected between the power switch tl+ and the converter (2), and allows the elevator to operate in the closed state, and allows operation in the open state. This is to prevent

Next, the operation of the above embodiment will be described.

Three-phase induction motor with variable voltage and variable frequency AC power (6)
The points of driving the heel (9) to raise and lower it, and the point of measuring the charging time of the smoothing capacitor (3) using the charging time measuring circuit 0 are the same as the conventional example shown in FIG.

Assume that the vehicle is currently in automatic operation and the normally open contact (21A) is closed. When the power switch (1) is closed,
Normally open contacts 6th floor and (13a) are closed. Operation mode check relay (2) is E)-) -(1,3a)-(
21A) - (21Bq) - (A) = (E) is energized by the circuit. It is self-retained via the normally open contact (20a) before the normally open contact (13a) is opened. Also, the operation inhibiting contactor I2 is energized via the normally open contact (20b) and the normally closed contact (14a), thereby closing the normally open contact (22a). The three-phase induction motor (6) is driven in the same manner as the conventional example shown in FIG.

Even if the capacity of the smoothing capacitor (3) decreases during automatic operation, the normally closed contact (j4a) remains closed, so automatic operation is interrupted.

Also, if there is a power outage during automatic operation, and when the power is restored, the smoothing capacitor (3) of each manufacturer has decreased.
Although the normally closed contact (14a) is opened.

Since the operation mode check relay wire is energized, the operation prevention contactor (2) is energized and automatic operation is continued.

Next, the case of 1-manual operation will be described. Since the run blocking contactor (23) is energized via the normally open contact (21B),
Operation can be continued regardless of the decrease in the capacity of the smoothing capacitor (3).

Next, a case will be described in which the power switch 111 is closed and the automatic operation is switched from manual operation to automatic operation.

Since the normally open contact (i3a) is open, the operation mode check relay wire remains deenergized. Furthermore, the normally open contact (21B) is opened due to automatic operation. At this time, assuming that a decrease in the capacity of the smoothing capacitor (3) is not detected, the normally closed contact (14a) remains closed, so the operation blocking contactor is energized (self-weight).
I operation becomes possible. Furthermore, if a decrease in capacity is detected, the normally closed contact (14a) remains open, so when switching to automatic operation, the operation blocking contactor 0 is deenergized and automatic operation is inhibited.

Also, it is in 1 manual operation, and then the power switch (
1) is closed, and furthermore, the case where manual operation is switched to automatic operation will be described. If each unit of the smoothing capacitor (3) is low, this capacitance drop will be detected when the power switch (11) is closed, and the normally closed contact (14a) will remain open. During manual operation. As already mentioned, the run-preventing contactor is energized via the normally open contact (21B).When switching to automatic operation, the run-preventing contactor is deenergized and operation is prevented.

According to the above embodiment, when the power switch Il+ is closed, it is detected whether the capacity of the smoothing capacitor (3) has decreased.

Furthermore, operation is blocked when switching from manual operation to automatic operation. Manual operation is normally used by elevator maintenance personnel, so when automatic operation is blocked,
Because there are no passengers in the car.

Of course, there is no confinement, and maintenance personnel are also present at the elevator, so they can easily find a defective smoothing capacitor and replace it.

〔Effect of the invention〕

As described above, the present invention is directed to an elevator that converts direct current smoothed by a smoothing capacitor into variable frequency alternating current power to drive an alternating current motor.

When switching from manual operation when maintaining an elevator to automatic operation when transporting passengers, the detection circuit that detects a decrease in the capacity of the smoothing capacitor will now prevent automatic operation if it detects a decrease in capacity. Therefore, one passenger was not trapped in the car.

In addition, the maintenance personnel who had been in charge of the maintenance can replace the smoothing capacitor when they know that automatic operation is not possible, allowing prompt countermeasures to be taken.

[Brief explanation of the drawing]

FIG. 1 is an electric circuit diagram showing a conventional elevator control device, FIGS. 2 and 3 show an embodiment of the present invention, and FIG.
The figure is an electrical circuit diagram for preventing operation. FIG. 3 is a diagram corresponding to FIG. 1. In the diagram, (R), (S), and (T) are three-phase AC power supply, (3) is a smoothing capacitor, and (6) is three-phase AC electric power *
, (21A) is a normally open contact that is closed during automatic operation, (21
B) is a normally open contact that is closed during manual operation, Qno is an operation blocking contactor, and t1υ is a converter. (100) is a detection circuit. Note that the same reference numerals in Figure 1 indicate the same or equivalent parts. Agent Masuo Oiwa Figure 1

Claims (1)

[Claims] The DC power converted from AC power by a converter is smoothed by a smoothing capacitor, this smoothed DC power is converted to variable frequency AC power, and this AC power is used to drive an AC motor to operate a car. Operation prevention means includes a detection circuit for detecting a drop in the smoothing capacitor of each manufacturer, and prevents the automatic operation based on the detection result of the detection circuit when the elevator is switched from manual operation for maintenance to automatic operation for transporting passengers. An elevator control device that is characterized by being equipped with.