JP2010013299A - Constant power control system in sintering process of optical fiber preform manufacture, and constant power control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To safely carry out automatic restoration by an inexpensive method after power recovery. <P>SOLUTION: The constant power control system is provided with a control part 13 provided with each control circuit 11 for controlling normal power supplied from a main power source 5 to respective various equipment of an apparatus body 3 used in a sintering process of an optical fiber preform manufacture, an uninterruptible power source 9 for supplying emergency power to each control circuit 11 based on a sensing signal given by the detection of power cut-off when the normal power is cut, a buffer circuit 17 for preventing the keeping of an operation circuit from dropping down due to voltage depression when changed to the emergency power of the uninterruptible power 9 and a PID control circuit 19 for impressing pseudo voltage to each control circuit 11 from the uninterruptible power source 9 when the normal power is cut. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a constant power control system and a constant power control method thereof in a sintering process for manufacturing an optical fiber preform.

  In a conventional sintering process for manufacturing an optical fiber preform, a rod-shaped glass preform is inserted into the furnace core of the apparatus main body from above, and the upper end of the glass preform is inserted through a dummy rod or the like. While being held by the material feeding section, it is fed to the sintering furnace at an appropriate speed. The lower part of the large-diameter portion of the glass base material is heated by a heating part (heater) of the sintering furnace.

  Normal power is supplied from the main power source to a large number of facilities such as the heating unit (heater) of the sintering furnace of the apparatus main body and other various devices, and this normal power is controlled by each control circuit of the control device. .

  By the way, when the normal power is cut off, that is, when a power failure occurs, the operation circuit is not held. Since the quartz muffle is used in the above-described sintering process, the quartz muffle will be damaged if power is not restored within a few minutes after power interruption.

  Conventionally, when a power failure occurs, the power output setting (volume) is set to 0 by manual operation to restore power. Then, increase the output manually. The reason is that the operation circuit can be turned ON by setting the power output setting to zero.

  By the way, Patent Document 1 describes a power supply system for a multimedia multiplexing apparatus, although it is not a sintering process for manufacturing an optical fiber preform. In this power supply method, an abnormality of the main power supply that supplies power to each of a plurality of subrack is detected, and only the subrack having high importance is detected using an uninterruptible power supply that generates a secondary power supply for backup. A system for supplying the next power source is provided.

In Patent Document 2, although it is not a sintering process for manufacturing an optical fiber base material, an electronic component manufacturing apparatus is provided that performs work restoration and product protection at the time of a momentary power failure and that is low-cost. Backup is performed by an uninterruptible power supply having a power failure detection device between the main control device and the main power source. When the power failure detection signal of the power failure detection device is input to the control device, the control device monitors the power failure time, and according to the power failure time, the work is restored or the product status is monitored to protect the product. It is.
JP-A-9-305271 JP-A-9-252548

  By the way, in the conventional sintering process of manufacturing optical fiber preforms, the apparatus main body has many facilities such as a heating section (heater) of a sintering furnace and other various devices. Since a control device that controls normal power is provided, there is a problem that it is difficult to restore a large number of the above-mentioned facilities at once if power is restored by manual operation when a power failure occurs. .

  In addition, it is impossible to prepare a plurality of large uninterruptible power supplies corresponding to many facilities.

  Moreover, in patent document 1, it is the power supply system of a multimedia multiplexing apparatus, Comprising: It is difficult to apply to the sintering process of optical fiber base material manufacture. For example, using UPS to replenish power in the event of a power outage has traditionally been done, and secondary power needs to be replenished to a large number of facilities. Supplying power is not sufficient. After all, it is impossible in terms of cost to prepare a plurality of large uninterruptible power supplies corresponding to a large number of facilities as described above.

  Moreover, in patent document 2, although it has the effect of making it low-cost in the point of backing up with the uninterruptible power supply apparatus with respect to the main control apparatus instead of the whole apparatus, it applies to the sintering process of optical fiber base material manufacture. When considering this, there was a problem that it was difficult to restore a large number of the above-mentioned facilities at a time when the secondary power source of the uninterruptible power supply was restored to the main power source.

  In other words, since the control device itself has a function of a feedback circuit for controlling the temperature, even if the control device is supplemented by the secondary power source of the uninterruptible power supply in the event of a power failure, the control device uses the feedback circuit. In order to control the temperature, the maximum output state is obtained. Therefore, when power is restored in the maximum output state, the maximum output power is supplied to a large number of facilities at a time, resulting in a very serious state. Therefore, it is difficult to apply the system of Patent Document 2 to the sintering process for manufacturing the optical fiber preform.

  An object of the present invention is to provide a constant power control system that performs an automatic and safe recovery after power recovery by an inexpensive method in a sintering process for manufacturing an optical fiber preform.

In order to solve the above-mentioned problems, the constant power control system in the sintering process of optical fiber preform manufacturing according to the present invention is applicable to various devices of the apparatus main body used in the sintering process of optical fiber preform manufacturing. A control unit including each control circuit for controlling normal power supplied from the main power supply;
When the normal power is cut off, an uninterruptible power supply that supplies emergency power to each control circuit according to a detection signal that detects this cut off,
A buffer circuit that keeps the operation circuit from falling due to a voltage drop when switching to the emergency power of this uninterruptible power supply,
A PID control circuit that applies a pseudo voltage from the uninterruptible power supply to each control circuit when the normal power is interrupted;
It is characterized by comprising.

The constant power control method in the sintering process of the optical fiber preform manufacturing method according to the present invention uses the normal power supplied from the main power supply to various devices of the apparatus body used in the sintering process of the optical fiber preform manufacturing. Control by each control circuit,
When the normal power is cut off, an emergency power is supplied from the uninterruptible power supply to the control circuits by a detection signal that detects the power cut.
The buffer circuit compensates for the voltage drop so that the operation circuit holding does not drop due to the voltage drop when switching to the emergency power of the uninterruptible power supply,
When the normal power is cut off, by applying a pseudo voltage from the uninterruptible power supply to each control circuit by the PID control circuit, the output control signal by each control circuit is lowered,
When the normal power is restored, the buffer circuit compensates for the voltage drop so that the operation circuit holding does not drop due to the voltage drop when switching from the emergency power of the uninterruptible power supply to the normal power of the main power supply,
The control circuit automatically raises the output control signal gradually and restores the standby power.

  As will be understood from the means for solving the problems as described above, according to the constant power control system and the constant power control method in the sintering process of optical fiber preform manufacturing according to the present invention, the power failure is an uninterruptible power supply. When the time is shorter than the holding time, the optical fiber preform manufacturing and sintering process can be automatically restored without damaging each facility. As a result, no labor is required at the time of restoration, so no effort is required for restoration.

  Further, since the system protects each control circuit of a large number of facilities using a small uninterruptible power source, a large-capacity uninterruptible power source that backs up the entire facility becomes unnecessary. In addition, since a pseudo voltage is applied to each control circuit of the control unit by PID control at the time of a power failure, the power output command can be issued from 0% at the time of recovery, so that it can be safely and automatically recovered at the time of power recovery. This can be done at low cost.

  In addition, since a buffer circuit is installed between the uninterruptible power supply and the control unit, it is possible to prevent the operation circuit from being held down due to an instantaneous voltage drop or an instantaneous voltage drop when switching the circuit to the uninterruptible power supply. . Therefore, it is possible to stably supply power even when the uninterruptible power supply is exchanged during energization (manufacturing), instantaneous voltage drop, and input voltage fluctuation.

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

  Referring to FIG. 1, a constant power control system 1 in a sintering process of manufacturing an optical fiber preform according to this embodiment includes a main power source supplied to various devices of an apparatus main body 3 used in the sintering process. This is a system for holding the operation circuit 7 by, for example, a UPS 9 as a small uninterruptible power source when the power failure occurs at 5 and automatically and safely recovering after power recovery.

  In the sintering process for manufacturing the optical fiber preform, a rod-shaped glass preform (not shown) is inserted from above into the furnace core of the sintering furnace of the apparatus body 3, and the upper end of the glass preform is inserted through a dummy rod or the like. And is fed to the sintering furnace at an appropriate speed. The lower part of the large-diameter portion of the glass base material is heated by a heating part (heater) of the sintering furnace.

  The apparatus main body 3 has a large number of facilities such as a heating unit (heater) of a sintering furnace and other various devices, and normal power is supplied from the main power source 5 to the large number of facilities. Moreover, the control part 13 which has each control circuit 11 which controls the normal electric power of each said installation is provided. The control unit 13 includes a feedback circuit 15 that feeds back the power value supplied to each facility to each control circuit 11.

  Furthermore, a UPS 9 that supplies emergency power (commercial power) to each control circuit 11 of each facility when the normal power is cut off (power failure) is connected to the control unit 13. Note that the retention time (UPS capacity) of the UPS 9 is set to an appropriate value within the breakdown of the apparatus. For example, in the sintering furnace of this embodiment, the retention time of UPS 9 is about 6 minutes. As a result, after the power is restored within the retention time of the UPS 9, the standby power can be automatically restored.

  In addition, an operation circuit 7 is provided that switches the normal power of the main power supply 5 to the emergency power of the UPS 9 based on a detection signal that detects that the normal power of the main power supply 5 is cut off (power failure). More specifically, the operation circuit 7 is provided with, for example, a B-contact relay that is always ON when energized, and detects the power failure by using the B-contact of the relay. An emergency power is supplied to each control circuit 11 of the control unit 13 by switching to the UPS 9 (backup power supply) by the detection signal of the relay operated by the B contact.

  Further, a buffer circuit 17 is provided between the circuits of the UPS 9 and the control unit 13. The buffer circuit 17 is a circuit for preventing the operation circuit from being held down by a voltage drop when the UPS 9 is switched to the emergency power using, for example, a capacitor or a transformer. More specifically, when switching to the emergency power of the UPS 9, an instantaneous voltage drop occurs for 10 to 20 msec. Therefore, the buffer circuit 17 holds the power until the emergency power of the UPS 9 is supplied. be able to. During the subsequent power failure, the output of each control circuit 11 of the control unit 13 can be held by supplying emergency power from the UPS 9.

  The control unit 13 is provided with a PID control circuit 19 that applies a pseudo voltage to each control circuit 11 using the emergency power of the UPS 9 when the normal power of the main power supply 5 is cut off. The PID control circuit 19 is, for example, a circuit in which a transformer for inputting a pseudo voltage to the input part of the feedback circuit 15 using the emergency power of the UPS 9 during a power failure.

  In this embodiment, a timer relay (not shown) is provided to allow the external cutoff signal to have a delay time within an allowable range so that the main power supply 5 does not trip due to peripheral device interlock immediately after power recovery. Therefore, when there is a switching operation to UPS 9 due to a power failure and instantaneous voltage drop, this is maintained, and the lamp is lit until the confirmation push button (PB) is pressed even after the main power supply 5 is restored. .

  With the above configuration, normal power is supplied from the main power supply 5 to each facility such as various devices of the apparatus main body 3 used in the sintering process of manufacturing the optical fiber preform. At this time, normal power for various devices of the apparatus main body 3 is controlled by each control circuit 11 of the control unit 13.

  When the normal power is cut off (power failure), the relay is operated by the B contact of the operation circuit 7 and is switched to UPS 9 (backup power supply) by the detection signal, and is used for each control circuit 11 of the control unit 13 as an emergency. Power is supplied.

  At this time, a momentary voltage drop occurs when switching to the UPS 9, but the voltage drop can be compensated by a capacitor and a transformer of the buffer circuit 17 so that the operation circuit holding is not lowered by this voltage drop.

  In addition to this, the control unit 13 applies a pseudo voltage from the UPS 9 to each control circuit 11 by the PID control circuit 19 when the main power supply 5 fails. Therefore, the output control signal from each control circuit 11 is lowered. I can leave.

  More specifically, in general, when the normal power from the main power supply 5 is cut off, the output feedback by the feedback circuit 15 becomes 0 (zero) during a power failure. The output command is generated. Therefore, each control circuit 11 stops in a state where the maximum output command is generated.

  However, in this embodiment, since a pseudo voltage is input to the input unit of the feedback circuit 15 using the emergency power of the UPS 9 by the PID control circuit 19, the output command from each control circuit 11 of the control unit 13 is 0 ( Zero). That is, as the above pseudo voltage, a voltage larger than normal use is input, so that the output command of each control circuit 11 is maintained in a 0 (zero) state during a power failure. As a result, a slow start from 0 is made when power is restored.

  In this embodiment, when the normal power of the main power supply 5 is restored within the holding time (UPS capacity) of about 6 minutes of the UPS 9, a voltage drop occurs when switching from the emergency power of the UPS 9 to the normal power of the main power supply 5. However, the buffer circuit 17 can prevent the operation circuit from being held down by the voltage drop.

  When the main power supply 5 is restored to the normal power, the output command from each control circuit 11 of the control unit 13 starts from 0 (zero) as described above, and the output control signal is automatically sent to various devices. It gradually rises and can be restored to standby power.

  From the above, the constant power control system 1 of this embodiment is such that when the power failure is short within the retention time (UPS capacity) of the UPS 9, the optical fiber preform is not damaged without damaging each equipment such as quartz muffle. The production sintering process can be automatically restored. As a result, no labor is required at the time of restoration, so no effort is required for restoration.

  Further, since the system protects only each control circuit 11 of a large number of facilities using a small UPS 9 (uninterruptible power supply), a large-capacity UPS 9 that backs up the entire facility becomes unnecessary. Moreover, since a pseudo voltage is applied to each control circuit 11 of the control unit 13 by the PID control circuit 19 at the time of a power failure, since a power output command can be issued from 0% at the time of recovery, sudden MAX and hunting can be prevented. It can be automatically and safely restored when power is restored. This can be done at low cost.

  In particular, the operation circuit 7 is configured by a relay sequence, and the power output command is 0% (output volume is 0 position) as a condition for turning on the power of the operation circuit 7. It is effective when each equipment is damaged unless the return is within a few minutes.

  Further, since the buffer circuit 17 is installed between the UPS 9 and the control unit 13, the holding of the operation circuit can be prevented from dropping due to an instantaneous voltage drop or an instantaneous voltage drop when switching the circuit to the UPS 9. Therefore, it is possible to stably supply power even when the UPS 9 is exchanged during energization (manufacturing), instantaneous voltage drop, and input voltage fluctuation.

It is a schematic block diagram of a constant power control system in a sintering process of manufacturing an optical fiber preform according to an embodiment of the present invention.

Explanation of symbols

1 constant power control system 3 main unit 5 main power supply 7 operation circuit 9 UPS (uninterruptible power supply)
11 Control Circuit 13 Control Unit 15 Feedback Circuit 17 Buffer Circuit 19 PID Control Circuit

Claims (2)

A control unit including each control circuit for controlling normal power supplied from the main power supply to various devices of the apparatus main body used in the sintering process of optical fiber preform manufacturing;
When the normal power is cut off, an uninterruptible power supply that supplies emergency power to each control circuit according to a detection signal that detects this cut off,
A buffer circuit that keeps the operation circuit from falling due to a voltage drop when switching to the emergency power of this uninterruptible power supply,
A PID control circuit that applies a pseudo voltage from the uninterruptible power supply to each control circuit when the normal power is interrupted;
A constant power control system in a sintering process for manufacturing an optical fiber preform. Control the normal power supplied from the main power supply to each device of the device body used in the sintering process of optical fiber preform manufacturing with each control circuit,
When the normal power is cut off, an emergency power is supplied from the uninterruptible power supply to the control circuits by a detection signal that detects the power cut.
The buffer circuit compensates for the voltage drop so that the operation circuit holding does not drop due to the voltage drop when switching to the emergency power of the uninterruptible power supply,
When the normal power is cut off, by applying a pseudo voltage from the uninterruptible power supply to each control circuit by the PID control circuit, the output control signal by each control circuit is lowered,
When the normal power is restored, the buffer circuit compensates for the voltage drop so that the operation circuit holding does not drop due to the voltage drop when switching from the emergency power of the uninterruptible power supply to the normal power of the main power supply,
A constant power control method in a sintering process of optical fiber preform manufacturing, characterized in that an output control signal is gradually gradually raised by each control circuit to restore standby power.

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