JPH01321277A - Controller of elevator - Google Patents

Abstract

PURPOSE:To rescue persons inside a cage by opening the contact of a defective inverter according to the operation of a trouble detecting circuit and changing over the operation instruction circuit to an abnormal-state running speed instruction circuit used during the trouble. CONSTITUTION:When the element 25a of 25a to 25f consisting of an inverter 6 is broken, overcurrent flows through a circuit consisting of a converter 3a, a contact point 4a, the element 25a, an element 25f, a contact point 4b and a converter 3a. This current is measured by a current detector 13 and a trouble detecting circuit 15 is actuated to interrupt the current control circuit 20 of the inverter and the contact point 2 of an electro-magnetic contact is opened to halt the elevator so that the cage 29 goes to a stop between floors. Simultaneously, the contact points 4a to 4c are opened to isolate the inverter 6 and a change-over device 16 is changed to make connection to an abnormal-state running speed instruction circuit 18. Therefore the current under the rated current flows through the inverter 9 and the elevator restarts with this current so that with the elevator reduced in speed and acceleration speed, the persons inside the cage can be rescued.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] This invention relates to an improvement in an elevator control device using an inverter.

[Conventional technology]

When controlling an elevator using an inverter, when each component is installed in parallel to compensate for the lack of current capacity of the inverter's components, one of the above components
If one of the devices turns on and fails, an excessive current will flow and there is a risk that other devices than those mentioned above will also be destroyed. Therefore, a method is used to cut off the human power from the power source so that a current exceeding the rated value does not flow into the inverter.

However, in this case, the elevator suddenly stops, leaving the passengers in the car crammed together.

To rescue the passengers inside the car, it is necessary to provide another system to drive the elevator.

For example, there is a method of driving an elevator by providing a battery and an inverter and connecting it to an electric motor, but this method has the drawback that the battery, inverter, and its control circuit must be installed, making it expensive.

FIG. 2 is a circuit diagram showing a conventional inverter control device similar to that shown in, for example, Japanese Unexamined Patent Publication No. 82-155776. In the figure, (1) is a three-phase AC power supply, (3a
) and (3b) are converters that are connected to the AC power source (1) through the contacts (2) of the electric 6i1 contactor and operate respectively during power flow and regeneration, and (21) is the converter (3a).
, (3b) is a smoothing capacitor connected to the DC side to smooth the DC output, (22) is a current detector connected between the capacitor (21) to smooth the converter output and the inverter (23), (23) is an inverter that is connected to both ends of the smoothing capacitor (21) and converts direct current to alternating current.This inverter is connected to both ends of the smoothing capacitor (21) to convert direct current into alternating current. Constituent elements (25g) ~ (2
5J2) are connected in parallel, and this inverter output is connected to a three-phase induction motor (1
2) to drive the elevator.

Therefore, (26) is a failure detection circuit that sends out a failure detection signal when the current detector (22) exceeds a certain value;
19) is a speed control circuit that generates a torque current command necessary for the electric motor (12), and (20) is a current control circuit that generates a current suitable for the elevator load based on the torque current command. is adapted to control the output of the inverter (23) to stop when it receives the failure detection signal.

Also, (27) is a speedometer generator that is directly connected to the electric motor (12) and emits a speed signal, (28) is a sheave, and (29)
indicates the car, and (30) indicates the counterweight.

In the above configuration, when a starting command is given to the electric motor (12), the electromagnetic contactor (2) is closed based on this starting command, and the converter (3a) and smoothing capacitor (18) are closed.
, the AC power converted via the inverter (19) and the reactor (20) is supplied to the electric motor (12), and the electric motor (
12) is activated.

(Problems to be Solved by the Invention) As described above, in the conventional inverter control device, when the current capacity of one element constituting the inverter is insufficient,
Since these elements are used in parallel, there is a problem in that if even one of these elements fails to turn ON, the inverter stops functioning and the elevator suddenly stops, making it impossible to use the elevator thereafter.

This invention was made to solve the above-mentioned problems, and by changing the method of paralleling the inverter components, even if one inverter fails, if the other inverter is normal, this inverter can be operated. An object of the present invention is to obtain an elevator control device that can be used to drive an elevator and rescue passengers in a car.

[Means to solve the problem]

The inverter control device according to the present invention includes at least two
A circuit or more inverters connected in parallel, a contactor connected to the input and output of each of the inverters, a failure detection circuit connected to each of the inverters to detect a failure, and a current control circuit that commands the output current of the inverter. , a normal running speed command circuit that generates the rated speed and specified acceleration when normal, a faulty running speed command circuit that generates a speed command that lowers the rated speed and acceleration when there is a failure, and a normal running speed command circuit that generates a speed command that lowers the rated speed and acceleration when the current control circuit is A switching device for switching between a traveling speed command circuit and a faulty traveling speed command circuit is provided, which opens a contactor of a faulty inverter based on the operation of the failure detection circuit, and switches the operation command circuit to the faulty traveling speed command circuit in the event of an abnormality. This is to switch to .

[Effect]

In the rescue of an abnormal elevator in this invention, the faulty inverter is disconnected and the normal inverter is used to lower the speed and acceleration of the elevator, thereby allowing the elevator to run to the nearest floor and rescuing the passengers inside the car.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to FIG. 1, in which the same parts as in FIG. 2 are denoted by the same reference numerals. In Figure 1, (4a), (4b) and (4C) are converters (3a
), (3b) are the contacts of the electromagnetic contactor connected to the DC side, the contacts of the electromagnetic contactor connected to the inverter (6) or the output side of the accelerator (10), and (6) are the smoothing capacitors. (5) A first inverter is connected to both ends of the inverter, and each component of this inverter is composed of a parallel connection of a transistor and a diode. (7a), (7b) and (7C) are the contacts (4a), (4b) of the above magnetic contactor,
Similarly to (4c), the contacts of the electromagnetic contactors connected to the DC side of the converters (3a) and (3b) and the contacts of the electromagnetic contactors connected to the inverter (9) or the output side of the accelerator (11). Contact point (8) is the first smoothing capacitor (5)
The smoothing capacitor (9) is connected to the DC side of the second inverter (9) to smooth the DC output, while the smoothing capacitor (9) is connected to the DC side of the second inverter (9).
A second inverter (10) and (11) is connected to both ends of the inverter (10) and (11) and is configured of transistors and diodes and converts direct current to alternating current in the same way as the first inverter (6).
) are the first and second inverters (6) and (9), respectively.
(13) and (14) are smoothing capacitors (5), (8) and inverters (8), (9), respectively.
), a current detector (15) connected between the inverter current control circuit (20
), disconnects the inverter whose detected current exceeds a certain value, and issues a switching command to switch the elevator speed command; (16) is a fault detection circuit that issues a switching command from the fault detection circuit (15); a switching device that switches from the rated speed and acceleration (17) of the elevator during normal operation to the speed and acceleration of the elevator at the time of failure when the
17) shows a normal running speed command circuit that generates a rated speed and a predetermined acceleration when normal, and (18) a faulty running speed command circuit that generates a speed command that lowers the rated speed and acceleration when a failure occurs.

In addition, in Fig. 2, a and b show the elevator speed curve and the torque and current curves of the electric motor (12) during normal full-load rising operation, while C and d show the full-load rising operation during failure. The elevator speed curve and the torque and current curves of the electric motor (12) are shown, and the operation will be described below.

In the above configuration, when a starting command for the electric motor (12) is given, the contact (2) of the electromagnetic contactor closes, and the converters (3a), (3b), electromagnetic contactors (4a), (4b),
(7a), (7b), smoothing capacitor (5), (8
), inverters (6), (9), reactors (10), (11), and electromagnetic contactors (4c), (7C), AC power is supplied to the electric motor (12).
) will start.

A speed command signal from the normal running speed command circuit (17) passes through the speed control circuit (19) and becomes a torque command, and a current command of a magnitude corresponding to this command is sent to the current control circuit (20).
), which controls the output currents of the inverters (6) and (7) (see FIG. 3(b)).

As a result, the speed of the electric motor (12) is controlled (Fig. 3 (
(see a)), the ride heel (29) runs up and down.

During normal operation, the components (25a) of the inverter (6)
(25f), when element (25a) turns on and fails, overcurrent flows through the circuit of converter (3a) - contact (4a) - element (25a5 - element (25f) - contact (4b) - converter (3a)) .This current is detected by a current detector (13
), the failure detection circuit (15) operates to stop the inverter's current control circuit (20), and opens the contact (2) of the magnetic contactor to stop the elevator, so the car (29) is not on the floor. Stop in between. At the same time, the contactor contact (4a)
- (4C) is opened and turned on to disconnect the inverter (6) including the failed element (25a) and switch the switching device (16) to the failed traveling speed command circuit (18) side. Since the inverter (6) is disconnected in the event of a failure, the current upper limit value IO for the rated current ■8 of the inverter elements is given, and the current control circuit (
20) is limited to 10 or less by the current command. Therefore, the current flowing through the inverter elements is also limited to below IR.

The reason is explained below.

The torque To that follows the torque curve in one run is To = Acceleration torque + Load torque (Here, load is required in all cases of acceleration, constant speed, and deceleration), and the acceleration torque is T
= Jα (J: moment of inertia, α: angular acceleration), and the moment of inertia is not changed. As for the angular acceleration, the longer the acceleration time, the lower the angular acceleration of the torque curve d. If α is set as a station in an elevator, the acceleration torque will be at a station, but the torque during running will be approximately %. On the other hand, the current of the electric motor (12) is TOC
Since there is a relationship of I, if the torque is reduced to approximately %, the electric motor (12
) is also approximately %.

As described above, even if one of the elements used in the inverter fails, the elevator can be started using the other inverter.

〔Effect of the invention〕

As described above, according to the present invention, when one of the inverters used in parallel fails, this inverter is disconnected and the other inverter is used to limit the current flowing to this inverter and reduce the speed and acceleration of the elevator. Passengers trapped inside can be rescued.

4. Brief explanation of drawings 8.
FIG. 1 is a block diagram of an embodiment of the present invention, FIGS. 2 and 2 are block diagrams of a conventional example, and FIG. 3 is a waveform diagram for explaining the present invention.

(4a) to (4c), (7a) to (7c) are contacts of magnetic contactors, (5) and (8) are smoothing capacitors, (Ii)
, (9) is the inverter, (15) is the failure detection circuit, (
17) is a normal running speed command circuit, (18) is a faulty running speed command circuit, (16) is a switching device, and (20) is a current control circuit.

In each figure, the same reference numerals indicate the same or corresponding parts.

Figure 3 Procedural amendment (voluntary) 2. Name of the invention Elevator control device 3. Representative of the person making the amendment Moriya Shiki 6. Contents of the amendment (1) Page 4 of the specification, lines 11 to 12 The description "smoothing capacitor (18), inverter (19) J" is corrected to "smoothing capacitor (21), inverter (23) J.

(2) The description "Fig. 2" on page 8, line 1θ of the specification is corrected to "Fig. 3."

(3) The statement “Eng.□” on page 10, line 6 of the specification
Correct it as Io J.

(4) The statement "load is" on page 1, line 10 of the specification is corrected to "load torque is".

(5) On page 10, lines 13 to 15 of the specification, the statement ``The moment of inertia... decreases.'' was replaced with ``If the moment of inertia remains unchanged, if the angular acceleration is decreased, the acceleration torque will decrease. ” he corrected.

(6) Drawing 9 Figures 1 and 2 will be corrected as shown in the attached sheet.

7. Catalog drawing of attached documents
1 or more

Claims (1)

[Claims] at least two circuits of inverters connected in parallel; a contactor connected to the input and output of each of the inverters;
A failure detection circuit that is connected to each of the above inverters to detect a failure; a current control circuit that commands the output current of the inverter; a normal running speed command circuit that generates a rated speed and a predetermined acceleration under normal conditions; is equipped with a fault running speed command circuit that generates a speed command that lowers the rated speed and acceleration, and a switching device that switches between the normal running speed command circuit and the fault running speed command circuit in the current control circuit, and controls the operation of the fault detection circuit. What is claimed is: 1. A control device for an elevator, characterized in that the contactor of a faulty inverter is opened based on this, and the operation command circuit is switched to the above-mentioned faulty traveling speed command circuit in the case of an abnormality.