WO2007023675A1

WO2007023675A1 - Controller of ac elevator

Info

Publication number: WO2007023675A1
Application number: PCT/JP2006/315743
Authority: WO
Inventors: Shuichi Masuzoe
Original assignee: Kabushiki Kaisha Yaskawa Denki
Priority date: 2005-08-25
Filing date: 2006-08-09
Publication date: 2007-03-01

Abstract

A controller of an AC elevator which does not require an expensive load detector. The controller of an AC elevator, which comprises a normal power supply RST, a DC power supply EB, an inverter INV, an induction motor IM for driving an elevator, and a section for commanding the operational direction of the elevator to a specified direction, and which supplies power to the induction motor from the DC power supply and the inverter to rotate it in the specified direction when the normal power supply is interrupted, is further provided with a section CT for detecting the output current value from the inverter after power is supplied to the induction motor, a forward/reverse operating section performing a forward operation and a reverse operation after elapse of a predetermined time, a section for comparing the output current values during the forward operation and the reverse operation at the forward/reverse operating section, and a section for automatically operating it in a rotational direction providing a lower output current value as a result of the comparison at the output current value comparing section.

Description

AC elevator control device

Technical field

TECHNICAL FIELD [0001] The present invention relates to an AC elevator operation control device in the event of a power failure in which an elevator is rescued using a DC power source during a normal power failure, and more particularly to control of the AC elevator operation direction in the event of a power failure.

Background art

[0002] Conventionally, when an elevator is rescued using a DC power source in the event of a power failure, the elevator operates even after a predetermined time has elapsed after issuing an operation command in the light load direction detected by the load detection device. There is a known technique for switching the driving direction if the driving speed does not reach the specified direction or if the driving speed does not reach the predetermined value even if it is started or reverses (Patent) Reference 1).

Patent Document 1: Japanese Patent Publication No. 58-13470

Disclosure of the invention

Problems to be solved by the invention

[0003] The prior art requires a load detection device to determine the driving direction, and there is a problem that the cost increases accordingly.

The object of the present invention is to solve these problems, and it is possible to operate an AC elevator with a small-capacity DC power source at the time of a power failure at a low cost without the need for a load detection device. The object is to provide an operation control device for an AC elevator.

Means for solving the problem

[0004] In order to achieve the above object, an invention according to claim 1 relates to an AC elevator control device, comprising a normal power source, a DC power source, an inverter device, an elevator driving induction motor, and a predetermined direction. An operation direction command unit that commands the operation direction of the elevator, and supplies power to the induction motor so as to rotate in the operation direction from the DC power source and the inverter device in the event of a power failure of the normal power source! Output current value detection for detecting the output current value of the inverter device after feeding power from the inverter device to the induction motor. An output section, a forward / reverse operation section that performs forward rotation and reverse operation after a lapse of a predetermined time, an output current value comparison section that compares output current values during forward and reverse operation by the forward / reverse operation section, and the output current It is characterized by having a rotation direction automatic operation unit with a small current that automatically operates in the direction of rotation with a smaller output current by comparison of the value comparison unit.

The invention according to claim 2 is the AC elevator control apparatus according to claim 1, wherein each torque of the induction motor is obtained and compared from each output current value during forward and reverse operation by the forward / reverse operation unit. A torque comparison unit and a rotation direction automatic operation unit for small torque that automatically operates in a rotation direction with a smaller torque by comparison of the torque comparison unit are provided.

The invention described in claim 3 is characterized in that, in the control device for an AC elevator according to claim 1, the output current value is measured by a current value measuring device.

The invention's effect

[0005] With the configuration as described above, the operation is automatically performed in the direction of light load, so that it is not necessary to provide an expensive load detection device, and the operation control of the elevator during a power failure is a heavy burden on the motor. Will be able to do without.

Brief Description of Drawings

FIG. 1 is a block diagram showing an example of a main circuit configuration of an elevator to which the present invention is applied.

FIG. 2 is a time chart showing an operation example when the reverse rotation in the first embodiment is a light load.

FIG. 3 is a time chart showing an operation example when forward rotation is light load in the first embodiment.

FIG. 4 is a time chart showing an operation example when the reverse rotation is a light load in the case of Example 2.

FIG. 5 is a time chart showing an operation example when the normal rotation in the second embodiment is a light load.

Explanation of symbols

[0007] RST "'Common power supply

直流 DC power supply

ΙΝν ··· Inverter device

GD '' 'Gate voltage supply circuit

中央 υ · · · Central processing unit

CT- 'Inverter output current value measuring device 三 ··· Three-phase induction motor

トラ · · · Traction machine

RCC ··· Ringing 'choke' converter

F ... car

W—Counterweight

(A), (Β) · · · ······ Main power contactor RST side main circuit contactor

(C), (D) ... DC power supply Main circuit contactor on the side

(Ε) · · · Main circuit contactor for inrush current suppression

_(F) … Battery operation command

(G) —Operation command

II · · 'Output current value of the inverter device during forward rotation

12 '· Inverter output current value during reverse operation

T1 · · 'Torque of three-phase induction motor during forward operation

T2- 'Torque of three-phase induction motor during reverse operation

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the present invention will be described in detail with reference to the drawings.

Example 1

FIG. 1 is a block diagram showing an example of a main circuit of an elevator according to Embodiment 1 of the present invention.

In the figure, the three-phase induction motor IM directly connected to the traction machine TM is normally supplied with power from the normal power supply RST via the inverter INV. The Traction Machine TM has a car F force on one side via a rope and a counterweight W on the other side.

By the way, when the common power supply RST fails, the three-induction motor IM is supplied with power from the DC power source EB (battery, etc.) via the inverter INV that converts DC to AC.

The inverter device INV is composed of six transistor covers. The output power from the gate voltage supply circuit GD is inverted when it is supplied to the gates of the transistors in a predetermined order. INV power Three-phase AC power is output. This flows into the primary winding of the three-phase induction motor IM and generates a rotating magnetic field, thereby causing the three-phase induction motor IM to rotate in either the forward or reverse direction during a power failure, causing the load elevator to run up or down. The predetermined order of the outputs from the gate voltage supply circuit GD is determined according to the directionality specified by the central processing unit MPU.

[0010] If the normal power supply RST fails for some reason during V, elevator operation, the elevator stops suddenly and the main circuit contactors (A) and (B) on the normal power supply RST side are turned OFF. . Turn on the battery operation command (F), turn on the main circuit contactors (C) and (D) on the DC power supply EB side, and supply DC power to the inverter INV. Turn ON (E) after 2 seconds.

When the operation command (G) is turned ON to the inverter device INV, the three-phase induction motor IM starts to rotate in the direction to raise the car F at the frequency of battery operation.

In the figure, the two DC power supplies EB are because the specifications of the DC power supply for the main circuit power supply and the DC power supply for the control power supply during the notch operation are different.

[0011] By the way, if the loading amount of the car F is small, the vehicle can be lifted without any problem. However, if the loading amount is large, an operation command is issued in the direction of heavy load, and the drive output by the three-phase induction motor IM is output. The direction of the load torque is larger than the torque. Therefore, the elevator has a problem that it reverses against the starting lock or load torque.

In such a case, according to the present invention, the following processing is executed in the central processing unit MPU. The inverter device INV is rotated forward for a predetermined time, and the output current value of the inverter device INV is measured by the current value measuring device CT. Let this value be II. After stopping once, next reverse rotation operation for a predetermined time, and measure the output current value of the inverter device INV with the current value measuring device CT. This value is 12. Then, immediately after 12 measurements, compare II and 12.

As shown in FIG. 2, the central processing unit MPU determines that the current power is in the direction of the reverse operation, that is, the light load direction, and continues the reverse operation as it is.

However, as shown in Fig. 3, if the current in the direction of the reverse operation that is currently running is large, it is determined that the load is in the heavy load direction, and after stopping temporarily, the forward operation is started.

As a result, the driving direction of the elevator automatically switches and the elevator starts normally. To come.

Example 2

[0013] In the first embodiment, the method based on the comparison of the magnitudes of the output current values of the inverter device is used as the direction reversal condition. However, in addition to the method for comparing the magnitudes of the output current values, the inverter Output current value force There is also a method of calculating the torque of a three-phase induction motor and comparing the magnitude of the torque.

According to the second embodiment, the following processing is executed in the central processing unit MPU. The inverter device INV is operated in the normal direction for a predetermined time, and the torque of the three-phase induction motor is calculated from the output current value of the inverter device INV.

The method for calculating the torque of the three-phase induction motor from the output current value of the inverter device INV is as follows. In other words, in vector control, the magnitude and phase of the primary current (output current value) are controlled so that the current is distributed to the excitation current and torque current. Therefore, from the equivalent circuit of the induction motor, the primary current, excitation current, torque The current relationship is

Primary current = {(excitation current) ² + (torque current) ² } ^1/2 …

Since the excitation current is a set value, the torque current can be obtained if the primary current is known.

In this way, the inverter device INV is rotated forward for a predetermined time, and the output current value force of the inverter device INV is determined as T1.

-After stopping and then rotating in reverse for a predetermined time, the torque of the three-phase induction motor is calculated from the output current value of the inverter device INV. This value is T2. After obtaining T2, compare T1 and T2. As a result of the comparison, as shown in Fig. 4, if the torque in the direction of reverse operation that is currently running is small, it is determined that the load is light and the reverse operation is continued as it is. However, as shown in FIG. 5, if the torque in the direction of the reverse operation that is currently running is large, it is determined that the load is in the heavy load direction, and after stopping temporarily, the forward operation is started.

As a result, the operation direction of the elevator is automatically switched, and the elevator starts normally.

As described above, according to the present invention, it is not necessary to provide an expensive load detection device, and the operation control of the elevator at the time of power outage can be performed without a heavy burden on the electric motor. Industrial applicability It is possible to provide a control device that operates an AC elevator with a small-capacity DC power supply at the time of a power failure at a low cost without requiring a load detection device.

Claims

The scope of the claims

[1] An ordinary power source, a DC power source, an inverter device, an induction motor for driving an elevator, and an operation direction command unit for instructing an operation direction of the elevator in a predetermined direction. For supplying power to the induction motor from the DC power source and the inverter device so as to rotate in the operation direction!

An output current value detection unit for detecting an output current value of the inverter device after power is supplied from the inverter device to the induction motor; a forward / reverse operation unit that performs forward rotation and reverse rotation after a predetermined time; and the forward / reverse operation. The output current value comparison unit that compares the output current values during forward and reverse operation by the unit and the output current value comparison unit that automatically operates in the direction of rotation with the smaller output current according to the comparison of the output current value comparison unit An AC elevator control device comprising an automatic operation unit.

[2] The torque comparison unit that obtains and compares the torques of the induction motor from the output current values during normal and reverse operations by the normal / reverse operation unit, and the rotation of the smaller torque by comparing the torque comparison unit 2. The AC elevator control device according to claim 1, further comprising a small torque rotation direction automatic operation section that automatically operates in a direction.

3. The control device for an AC elevator according to claim 1, wherein the output current value is measured by a current value measuring device.