JPH09255254A - Elevator operating device at power stoppage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the cost of a device by connecting a battery to the DC side of the first inverter when a three-phase AC power source is stopped, feeding the output of the battery to a control circuit via the second inverter, incorporating the primary winding of a step-up transformer into a control transformer, and using an iron core in common. SOLUTION: When a three-phase AC power source 1 is operated normally, three-phase AC is converted into DC by a converter 3, it is smoothed by a smoothing capacitor 4, and it is fed to the first inverter 5 to drive a motor 6. The three-phase AC is transformed by a control transformer 12, and it is fed to a control circuit 9 to control the first inverter 5. At the time of a power stoppage, a battery 15 is connected to the DC side of the first inverter 5 via a diode 17, the battery 15 is also connected to the DC side of the second inverter 18, and the three-phase AC voltage is applied to the primary windings 21a, 21b of a step-up transformer. The DC voltage transformed by the control transformer 12 is fed to the control circuit 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for operating an elevator during a power failure.

[0002]

2. Description of the Related Art In recent years, an inverter has been used to control an electric motor for driving an elevator in order to reduce power consumption. Even during a power failure, a battery is connected to the DC side of the inverter to operate the elevator. It has been proposed. 5 and 6 are views showing a conventional elevator power failure operation device disclosed in, for example, Japanese Patent Publication No. 64-314, FIG. 5 is an overall configuration diagram, and FIG. 6 is a waveform diagram of each part. Since the details of this circuit will be described later, an outline of the operation will be described here.

When the three-phase AC power supply 1 is normal, the contacts 16 and 2
Since 0 is open and contact 11 is closed, when contact 2 is closed, three-phase alternating current is converted into direct current by converter 3,
It is smoothed by the smoothing capacitor 4, supplied to the first inverter 5, and applied to the electric motor 6. On the other hand, the three-phase alternating current is transformed by the control transformer 12, rectified by the rectifier 13,
It is smoothed by the smoothing capacitor 14 and supplied to the first control circuit 9, and the output corresponding to the input controls the first inverter 5.

With this, the first inverter 5 generates a three-phase AC voltage having a variable voltage and a variable frequency according to the output of the first control circuit 9 to control the rotation speed and torque of the electric motor 6 ( (Not shown) speed is controlled. Further, when electric power is regenerated from the electric motor 6, the first control circuit 9 detects this and makes the transistor 8 conductive, and causes the resistor 7 to consume the regenerated electric power.

On the other hand, when the three-phase AC power supply 1 fails, the contact 16 is supplied by the power from an emergency standby power supply (not shown) or the like.
Is closed, and the voltage of the battery 15 is applied to the DC side of the first inverter 5 via the diode 17. The voltage of the battery 15 is also applied to the DC side of the second inverter 18. On the other hand, since the contact 11 is open and the contact 20 is closed, the three-phase AC voltage output from the second inverter 18 is applied to the primary winding of the step-up transformer 33. Therefore, the DC voltage transformed by the control transformer 12, rectified by the rectifier 13 and smoothed by the smoothing capacitor 14 is the first DC voltage.
Is supplied to the control circuit 9.

Therefore, the first control circuit 9 controls the first inverter 5 and the transistor 8 to control the rotation speed and torque of the electric motor 6 as in the case where the three-phase AC power supply 1 is normal. Next, in FIG. _{6, E UV, E VW,} E WU
Is the output waveform of the second inverter 18 applied between the U-V phase, the V-W phase and the W-U phase of the step-up transformer 33, and t _on is the on time of the output waveforms E _UV , E _VW , and E _WU . , T
Is the same period, I _U is the U-phase current waveform, and V is the input current of the first control circuit 9.

When the battery 15 is connected at time t _o , the second
The control circuit 19 controls ON / OFF of the transistor of the second inverter 18. During the period a, the transistor is turned on and a current flows between the U and V phases of the step-up transformer 33. Period b
The other set of transistors is turned on, and a current flows between the W and U phases of the step-up transformer 33. Also in the period c, the other set of transistors is turned on, and a current flows between the V and W phases of the step-up transformer 33. The same operation is repeated thereafter, and the three-phase AC voltage is supplied to the step-up transformer 33.

At this time, the charging current I _U also flows to the primary side of the step-up transformer 33 due to the charging current of the smoothing capacitor 14 connected to the secondary side of the control transformer 12. I _UP is the inrush current value. Then, the secondary voltage of the control transformer 12 gradually rises, and the input voltage V of the first control circuit 9 also reaches Va at time t ₁ .

[0009]

In the conventional elevator power failure operation device as described above, the voltage of the battery 15 is converted into a three-phase AC voltage by the second inverter 18, and the three-phase AC voltage is further converted by the step-up transformer 33. Transformer for control 12 by boosting AC voltage
Therefore, there is a problem that the operating device at the time of power failure becomes expensive. Further, when the normal operation shifts to the power failure operation, the rush current to the smoothing capacitor 14 on the secondary side of the control transformer 12 causes the second inverter 1 to operate.
Since the transistor in 8 has to withstand the inrush current, a device having a large withstand voltage must be used, and the second inverter 18 becomes expensive.

The present invention has been made to solve the above-mentioned problems, and provides an elevator power failure operation device capable of preventing the step-up transformer and the second inverter from becoming expensive. With the goal.

[0011]

According to a first aspect of the present invention, there is provided an elevator power failure operating device, which is a primary winding of a step-up transformer connected to a second inverter for converting the output of a battery during a power failure into an alternating current. Is incorporated in a control transformer so that the core is shared.

Further, an elevator power failure operating device according to a second aspect of the present invention is the elevator of the first aspect, wherein the primary winding of the step-up transformer is provided separately from the primary winding of the control transformer and is V-connected. Is.

Further, an elevator power failure operation device according to a third aspect of the present invention is the same as that of the first aspect, wherein the two-phase primary windings of the control transformer are V-connected and the open side thereof is a step-up transformer. A terminal is used as a terminal, and a point where parts of two-phase primary windings are connected to each other is used as one terminal of the step-up transformer.

Further, the elevator power failure operation device according to the fourth aspect of the present invention is the second operation for converting the output of the battery at the time of power failure to alternating current.
The output frequency of the inverter is set higher than the frequency of the three-phase AC power supply.

In the elevator power failure operation device according to the fifth aspect of the present invention, the ON time of the output waveform of the second inverter that converts the output of the battery into AC for a predetermined time after the power failure is set shorter than after the predetermined time. It is something that is done.

Further, in the elevator power failure operating device according to the sixth aspect of the invention, the primary winding of the step-up transformer is incorporated in the control transformer, and the output frequency of the second inverter is higher than the frequency of the three-phase AC power supply. The predetermined time after the power failure is set so that the ON time of the output waveform of the second inverter is set shorter than the predetermined time.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1. FIG. 1 is an overall configuration diagram showing an embodiment of the first and second inventions of the present invention. In the figure, 1 is a three-phase AC power supply, 2 is a three-phase AC power supply 1, and an electromagnetic contactor contact that is closed when the elevator is running 3 is a converter that converts the three-phase AC power of the three-phase AC power supply 1 into DC Reference numeral 4 is a smoothing capacitor connected to the DC side of the converter 3.

Reference numeral 5 is connected to the smoothing capacitor 4 and is composed of a transistor and a diode.
M) A first inverter that converts direct current into three-phase alternating current of variable voltage / variable frequency by control, 6 is an elevator-driving three-phase induction motor connected to the alternating current side of the first inverter, and 7 is the first A resistor connected to the DC side of the inverter 5 and consuming the regenerative power from the electric motor 6 is a transistor connected to the resistor 7.

Reference numeral 9 is a first control circuit for controlling the transistor of the inverter 5 and the transistor 8 for consuming regenerative electric power.
Is connected to the inverter 5 and the transistor 8.
11 is a relay contact that is opened when the three-phase AC power source 1 is out of power, 1
Reference numeral 2 is a control transformer composed of a three-phase transformer, and its primary windings 12a1 and 12a2 are V-connected and connected to a contact 11. Reference numeral 13 is a rectifier connected to the secondary winding 12b of the control transformer 12, to which a smoothing capacitor 14 is connected on the direct current side, and is also connected to the first control circuit 9.

Reference numeral 15 is a battery for operation during a power failure, and 16 is a battery 1
5 is a magnetic contactor contact that is connected to the circuit 5 and is closed when the three-phase AC power supply 1 is shut down.
Is connected to the DC side of. 18 is composed of a transistor and a diode as will be described later, and has a pulse width modulation (P
A second inverter that converts the direct current of the battery 15 into a three-phase alternating current of a variable voltage and a variable frequency by WM) control, and 19 is a second control circuit that controls the transistor of the inverter 18.

A relay contact 20 is connected to the AC side of the second inverter 18 and is closed at the time of a power failure of the three-phase AC power supply 1.
Reference numerals 21a and 21b denote primary windings of the step-up transformer connected to the contact 20 and are incorporated in the control transformer 12. That is, the primary windings 21a and 21b share the iron core with the primary windings 12a1 and 12a2 of the control transformer 12, and are V-connected.

Next, the operation of this embodiment will be described.
When the three-phase AC power supply 1 is normal, the contacts 16 and 20 are opened,
Since the contact 11 is closed, when the contact 2 is closed, the three-phase alternating current is converted into direct current by the converter 3, smoothed by the smoothing capacitor 4, supplied to the first inverter 5, and applied to the electric motor 6. It On the other hand, three-phase AC is used for the control transformer 12
Is transformed by the rectifier 13, rectified by the rectifier 13, smoothed by the smoothing capacitor 14 and supplied to the first control circuit 9, and the first inverter 5 is controlled by the output corresponding to the input.

Thus, the first inverter 5 generates a three-phase AC voltage having a variable voltage and a variable frequency according to the output of the first control circuit 9 to control the rotation speed and torque of the electric motor 6 ( (Not shown) speed is controlled. Further, when electric power is regenerated from the electric motor 6, the first control circuit 9 detects this and makes the transistor 8 conductive, and causes the resistor 7 to consume the regenerated electric power.

On the other hand, when the three-phase AC power supply 1 fails, the contact 16 is supplied by the power from an emergency standby power supply (not shown) or the like.
Is closed, and a voltage is applied to the battery 15 via the diode 17 to the DC side of the first inverter 5. The battery 15 is also applied to the DC side of the second inverter 18. On the other hand, since the contact 11 is open and the contact 20 is closed, the secondary windings 21a and 21b are connected to the secondary windings 21a and 21b of the step-up transformer 33.
The three-phase AC voltage that is the output of the inverter 18 is applied. Therefore, the DC voltage that has been transformed by the control transformer 12, rectified by the rectifier 13, and smoothed by the smoothing capacitor 14 is supplied to the first control circuit 9.

Therefore, the first control circuit 9 controls the first inverter 5 and the transistor 8 to control the rotation speed and torque of the electric motor 6 as in the case where the three-phase AC power supply 1 is normal. In this way, the primary windings 21a and 21b of the step-up transformer are the primary windings 12a of the control transformer 12.
Since both of the transformers 1 and 12a2 share the iron core and both transformers are integrated, the cost can be reduced compared to the case where a step-up transformer is separately provided.

Embodiment 2 FIG. FIG. 2 is a configuration diagram of a control transformer portion showing an embodiment of a third invention of the present invention, and the same reference numerals as those in FIG. 1 indicate the same or corresponding portions. In this embodiment, the primary windings 21a and 21b of the step-up transformer are shared with the primary windings 12a1 and 12a2 of the control transformer 12. That is, the contacts 20a, 20c are connected to the open side of the V-connected primary windings 12a1, 12a2, and the contact 20b is connected to a point where parts of the primary windings 21a1, 21a2 are connected to each other.

That is, during a power failure of the three-phase AC power supply 1, the contact 11 is opened and the contacts 20a to 20c are closed.
The step-up transformer is a three-phase transformer in which the primary windings 21a and 21b are V-connected, forms a power source for the first control circuit 9, and controls the inverter 5 and the transistor 8. Other than the above, it is the same as FIG. In this way, since the step-up transformer and the control transformer 12 are integrated, the cost can be reduced compared to the case where the step-up transformer is separately provided.

Embodiment 3. 3 and 4 are views showing the fourth and fifth inventions of the present invention, FIG. 3 is a configuration diagram of a second inverter and a second control circuit portion, and FIG. 4 is a waveform chart of each part. FIG. 1 is also used in the third embodiment.

In FIG. 3, reference numerals 24A to 24F are transistors, 25A to 25F are free-wheeling diodes for releasing a high voltage generated during the operation of the transistors 24A to 24F, 26 is an oscillation circuit for generating a reference clock signal, 27
4 is a waveform generation circuit that generates the output waveform shown in FIG. 4 based on the reference clock signal, 28 is a switching circuit that outputs a switching signal to the waveform generation circuit 27, and 29 is an output of the waveform generation circuit 27 that causes the transistors 24A to 24F to be switched. It is a base drive circuit for driving.

Next, the operation of this embodiment will be described with reference to FIG. In FIG. 4, E _UV, E _VW, E _WU the UV phase of each step-up transformer, the output waveform of the second inverter 18 to be applied between VW interphase and WU phases, t _on, t
_{On 1} is the on-time of the output waveforms E _UV , _{EV W} , and E _WU , T and T ₁ are the same period, I _U is the U-phase current waveform, and V is the input current waveform of the first control circuit 9. When the battery 15 is connected at time t _o , the base drive circuit 29 controls the transistors 24A to 24F to be turned on / off according to the output of the waveform generation circuit 27.

During the period a, the transistors 24A and 24D are turned on and between the U and V phases of the step-up transformer, that is, the primary winding 2
Rectify to 1a. The period c is the transistor 24A, 2
4F is turned on, and a current flows between the UWs of the step-up transformer, that is, the primary windings 21a and 21b. Below period e, g, i,
Similarly, the transistor k turns on / off the transistors 24A to 24F to flow a current through the primary windings 21a and 21b of the step-up transformer (the periods b, d, f, h, j, and l are the transistors 24A.
~ 24F is off). By repeating this, the three-phase AC power is supplied to the primary windings 21a and 21b of the step-up transformer. Then, the secondary winding of the control transformer 12 gradually rises, the input voltage V of the first control circuit 9 also rises, and Va
Reach

When the predetermined time t ₁ has elapsed, the switching circuit 28
Outputs a switching signal, and the output waveform of the waveform generation circuit is the same as in FIG. The second inverter 18 until the predetermined time t ₁
The on-time ton ₁ of the output waveform is set shorter than the on-time ton of the output waveform after the predetermined time t ₁ . Thereby, for example, the U-phase rush current Iup is the same as in the case of FIG.
Since the on-time ton ₁ is short and the non-energization time is generated, the average current per cycle is smaller than that in the case of FIG. 6, the current value relating to the heat generation of the transistors 24A to 24F is smaller, and the inrush current withstand capability is smaller. Can be raised.

Further, the output frequency of the second inverter 18 is higher than the frequency of the three-phase AC power supply 1 which is the output frequency after the predetermined time t ₁ until the predetermined time t ₁ (T ₁
<T). Here, the power P supplied to the control transformer 12
Is expressed by the following formula. P = VI = the _{(X L I) I = 2πfLI} 2 Here, V: Voltage I: Current X _L: inductive reactance f: Frequency L: mutual inductance

Therefore, in order to obtain the same power P, the current f can be reduced by increasing the frequency f, and the transistors 24A to 24F can be made to have low rated rectification. It should be noted that the current I _U gradually decreases for a predetermined time t ₁ from the time t _o , which is due to the transient phenomenon of the circuit. Further, the predetermined time t ₁
Before and after, the current value changed from I _UC1 to I _UC (I _UC1 <I _UC ), which is due to the switching of the frequency.

In the third embodiment, the output frequency of the second inverter 18 is set or the second inverter 1 is used in the circuit using the control transformer 12 incorporating the step-up transformer.
Although it has been described that the ON time of the output waveform of No. 8 is set, the present invention is not limited to this. That is, as shown in FIG. 5, it is obvious that the above setting may be made in a circuit in which the step-up transformer 33 and the control transformer 12 are separately provided.

As described above, in the first invention of the present invention, the primary winding of the step-up transformer connected to the second inverter for converting the output of the battery at the time of power failure into the alternating current is incorporated in the control transformer to make the iron core. In the second invention, since the primary winding of the step-up transformer is provided separately from the primary winding of the control transformer and V-connected, there is no need to provide a dedicated step-up transformer, and the device is inexpensively constructed. There is an effect that can be.

Further, in the third aspect of the invention, the primary winding of the control transformer is V-connected, and the open side and a part of the two-phase primary windings are connected to each other with the terminals of the step-up transformer. Therefore, the primary winding is shared, and there is an effect that the cost can be further reduced.

Further, in the fourth aspect of the invention, since the output frequency of the second inverter is set higher than the frequency of the three-phase AC power source, the peak value of the input rectification of the step-up transformer is suppressed to increase the inrush current withstanding capability, The device can be constructed at low cost.

Further, in the fifth invention, since the ON time of the output waveform of the second inverter is set to be short for the predetermined time after the power failure, the average current value is suppressed, the inrush rectification withstand capability is increased, and the device can be constructed at low cost. There is.

Further, in the sixth invention, the primary winding of the step-up transformer is incorporated in the control transformer, the output frequency of the second inverter is set higher than the frequency of the three-phase AC power supply, and the predetermined time after the power failure is set. Since the on-time of the output waveform of the second inverter is set to be short, it is not necessary to provide a dedicated step-up transformer, and it is possible to suppress the inrush current, increase the inrush current withstand capability, and reduce the cost of the device. is there.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a control transformer portion showing a second embodiment of the present invention.

FIG. 3 is a configuration diagram of a second inverter and a second control circuit showing a third embodiment of the present invention.

FIG. 4 is a waveform chart of respective parts showing the third embodiment of the present invention.

FIG. 5 is an overall configuration diagram showing a conventional elevator power failure operation device.

FIG. 6 is a waveform diagram of each part of FIG.

[Explanation of symbols]

1 3 Phase AC Power Supply, 3 Converter, 5 1st Inverter, 6 3 Phase Induction Motor, 9 1st Control Circuit, 12
Control transformer, 12a1, 12a2 primary winding of control transformer, 15 battery, 18 second inverter, 19
2nd control circuit, 21a, 21b Primary winding of a step-up transformer, 24A-24F transistor, 28 Switching circuit.

Claims (6)

[Claims] 1. A converter for converting a three-phase alternating current power supply to direct current, a first inverter for converting an output of the converter into a variable voltage / variable frequency alternating current and supplying the same to a hoisting motor, and the three-phase alternating current power supply. A first power source is supplied through a control transformer connected to the first power source to control the first inverter.
Control circuit, a battery connected to the DC side of the first inverter during a power failure of the three-phase AC power supply, a second inverter that converts the output of this battery into AC, and an output of this second inverter And a step-up transformer that has a primary winding connected to the control side and shares an iron core with the control transformer, and that supplies a power supply to the first control circuit. 2. The elevator power failure operation device according to claim 1, wherein the primary winding of the step-up transformer is provided separately from the primary winding of the control transformer and is V-connected. 3. A control transformer having a two-phase primary winding connected in a V-connection, the open side of the two-phase primary winding being the two terminals of a step-up transformer, and a part of the two-phase primary winding. 2. The elevator power failure operating device according to claim 1, wherein a point where the two are connected to each other is one terminal of the step-up transformer. 4. A converter for converting a three-phase alternating current power supply into a direct current, a first inverter for converting an output of the converter into a variable voltage / variable frequency alternating current and supplying the same to a hoisting motor, and the three-phase alternating current power supply. A first power source is supplied through a control transformer connected to the first power source to control the first inverter.
Of the three-phase AC power supply, a battery connected to the DC side of the first inverter at the time of a power failure of the three-phase AC power supply, and a second inverter that converts the output of the battery into AC. In the event of a power failure, an elevator power failure operating device in which the output frequency of the second inverter is set higher than the frequency of the three-phase AC power supply. 5. A converter for converting a three-phase alternating current power supply to direct current, a first inverter for converting an output of the converter into a variable voltage / variable frequency alternating current and supplying it to a hoisting motor, and the three-phase alternating current power supply. A first power source is supplied through a control transformer connected to the first power source to control the first inverter.
Control circuit, a battery connected to the DC side of the first inverter at the time of power failure of the three-phase AC power supply, a second inverter that converts the output of the battery into AC, and a power failure of the three-phase AC power supply. An elevator power failure operation device comprising a switching circuit for setting the ON time of the output waveform of the second inverter to be shorter than the predetermined time after the predetermined time. 6. The output frequency of the second inverter during a power failure of the three-phase AC power supply is set higher than the frequency of the three-phase AC power supply, and the output waveform of the second inverter is turned on for a predetermined time after the power failure. 2. The elevator power failure operating device according to claim 1, further comprising a switching circuit for setting the time shorter than after the predetermined time.