JP3102438B2 - Power demand control device for metalworking line - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a demand power control device for a metal working line.

(Prior Art) Conventionally, in a production line such as a sheet metal processing line, a demand controller that cuts off an unnecessary load and saves a power rate cannot be used due to a production priority. This is because, in a production line, it is necessary to operate a desired power at a desired time and to perform production as scheduled, and to prioritize productivity over electricity charges.

(Problems to be Solved by the Invention) However, if the demand controller cannot be introduced into the production line, there is a problem that the contract power rate is set due to a temporary overload and the contract power rate becomes enormous.

In addition, since demand controllers cannot be installed on the production line, if only the lighting circuit in the office is demand controlled, the sudden fluctuations in the load on the production line will have an effect, and the lighting circuit will be cut off frequently, greatly affecting office work. There is a problem that comes out.

Accordingly, the present invention provides a demand power control device for a metalworking line capable of suppressing demand power within a management target value without lowering production efficiency by coordinating a power receiving and distribution facility and a production line. With the goal.

[Constitution of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention provides a metal working machine equipped with a power load device including a plurality of metal working machines supplied with power from a predetermined power receiving and distributing facility. In the line, the power receiving and distribution equipment is provided with a power control data communication terminal of the power receiving and distribution equipment, while the power load equipment is provided with a power control data communication terminal of the power load equipment,
Further, a power control data communication terminal is provided in a management device managed by an operator of each power load device, and these data communication terminals are connected to each other to form a power control communication network.
A processing machine network composed of the respective metal processing machines is connected so as to enable data communication, and power is predicted to a data communication terminal of the management device based on a processing schedule of each metal processing machine transmitted from the processing machine network. Is calculated, and when the predicted power value is likely to exceed the management target value, means for outputting a power schedule change command is provided, while the processing machine network receives the power schedule change command and advances the machining schedule. A demand power control device for a metalworking line, comprising means for reconfiguring a processing schedule by performing an execution or changing an execution order and transmitting a new processing schedule to a data communication terminal of the management device.

(Example) Hereinafter, an example of applying the present invention to a production line for sheet metal processing will be described, and an example of the present invention will be described.

FIG. 2 is a block diagram showing a demand power control device for a metal working line embodying the present invention.

In the figure, a demand controller 3 and, for example, ten capacitor banks 4 are arranged in a cubicle (intelligent cubicle) 2 that accommodates a power receiving and distribution facility 1. The cubicle 2 has various detectors 5 such as various instruments and a temperature sensor for detecting room temperature.
And auxiliary equipment 7 such as switches 6 and ventilation equipment for each distribution line
And a signal input unit 8 for inputting a detection signal of each detector 5 and a signal output unit 9 for outputting a control signal to various controllers.
The data communication device 10 is connected to the signal input / output devices 8 and 9 so that the data communication terminal 11
Is configured.

Data communication device 10 or data communication terminal 11
May be provided in the cubicle 2, but since it is weak to the thermal environment, a separate box is provided outside the housing, housed in this box, and connected to the cubicle 2 via a communication line. May be.

On the other hand, from the power receiving and distributing equipment 1, a demand control power wiring 12 that can be controlled by the demand controller 3 and a non-control power wiring 13 that cannot be cut off by the demand controller 3 are output. Are controlled by the load-side (line-side) data communication terminals 14, 15, 16, 17, 18, 19,... Arranged for each load group (single load or collective load) classified as appropriate. Individual loads are connected via the container 20. Generally, the demand control power wiring 12 is wired to a light line on the office side, and the non-control power wiring 13 is wired to a line where the machine is arranged.

Line side data communication terminals 14, 15, 16, 17 as shown
Are a data communication device 10, a data processing unit 21, and a device control unit 22.
It is provided with. Also, data communication terminal 1
8 and 19 are of the type having no data processing unit 21.

Generally, the data communication terminals 14, 15,... Having the data processing section 21 are connected to a factory local area network (LA).
N) 23, a single processing line, and a group management unit that performs group management by integrating a plurality of loads. Further, the data communication terminals 18 and 19 having no data processing unit 21 are provided for one or a plurality of loads simultaneously for one command, or for a load capable of opening and closing control in a fixed sequence. .

Each data communication terminal 11, 14, 15, ... 19 has an address,
It is connected to a power control communication line 24 that communicates by data and programs to form a data communication network. However, the data communication terminals 18 and 19 without the data processing unit 21 can omit the data transmission function.

Further, the management side, which is easy to manage by the production line operator, communicates with each of the data communication terminals 11, 14, 15,... 19, performs various data processing, generates various control signals, A management-side data communication terminal 25 capable of giving automatic and manual operations to the cubicle 2 via the cubicle-side data communication terminal 11
Is connected.

The management-side data communication terminal 25 includes the communication unit 10, a data processing unit 26A, and an operation unit 26B. This terminal
25 may be shared with one of the line-side data communication terminals 14, 15, 16,...

 FIG. 3 is an explanatory diagram showing an example of a LAN.

As shown in the figure, the LAN 23 of this example is configured by connecting a main controller 27, an automatic programming device 28, a numerical control (NC) device 29, and a plurality of data processing devices 29 to each other on a communication line 20. , Each processing machine 31 in each data processing device 29
(31A, 31B, 31C) are scheduled to be operated.
It is assumed that the processing machine 31A is a punch press machine, 31B is a combined punch / laser processing machine, and 31C is a laser processing machine. A database 32 is appropriately connected to each member connected to the LAN 26.

The LAN 23 and the above-mentioned communication line 24 are appropriately connected via a communication line, and are configured to be able to exchange data with each other.

As an example of the schedule operation, the main controller 27 edits the execution order of the plurality of programs Pi (P1, P2,...) And the number of repetitions of each program, and issues an operation command to each processing machine 31 for each schedule. Is output, each processing machine 31 executes a scheduled operation as instructed next to the ON operation of the start button. Each of the processing machines 31 may be operated in a schedule in conjunction with each other.

The program Pi used for the scheduled operation is created by the automatic programming device 28. For example, when graphic data in which various numbers of holes are drilled in various places of a plate-like work are input to the automatic programming device 28, NC program data for numerically controlling the punch press machine 31A to sequentially drill holes is generated. Is done. Further, in the combined punch / laser machine 31B, programming is performed so as to perform laser processing on a portion of a hole shape that cannot be punched.

Therefore, in each processing machine 31, the scheduled program data is input, the program is sequentially executed at the set speed, and the product is sequentially processed.

However, if the power supply is cut off during the processing, the machine is stopped immediately, which is not only dangerous but also results in a defective product being processed. In addition, when the emergency stop button is pressed, the machine operates in the safe direction in principle and stops immediately, which often results in defective products. Furthermore, in the case of general suspension, in many cases, the processing is interrupted at the end of the current processing, so that one processing such as the laser processing machine 31C may take a long time. Except for this, the machining is interrupted without any defective products. In the case of the NC device, the origin return of the servo control circuit is not necessary in the case of a temporary stop,
In the case of an emergency stop, it must be restarted from the home position return operation.

As described above, in a processing machine including an NC device, power supply cutoff is forbidden, and if you want to shift the operation timing for a certain processing, you can shift the start time, change the contents of the program, or pause the improvement Signal must be given. The improvement pause signal is a signal that is particularly proposed in this example. By giving a pause command, the program is interrupted for the next machining after the machining is completed, and no defective product is generated. In this case, the machining can be continued with a return command. According to the signal of the improvement temporary stop, no defective product is generated even by laser processing.

FIG. 4 is an external view of the management-side data communication terminal 25.

The illustrated management data communication terminal 25 is also called an intelligent cubicle controller (ICC), and has a CRT screen 33, an operation switch group 34,
An LED lamp group 35 indicating a control state and a function switch group 36 are provided. The CTR screen 35 displays the current status and statistical values of the instruments, the operating status of the line, and the like.
From the switch group 34, in addition to remote control of the cubicle 2,
Various commands can be given. The function switch 36 can give various commands from a menu displayed below the screen 35. The lamp group 35 displays the control status of the demand controller 3 and the capacitor bank 4.

FIG. 5 is a block diagram showing a detailed configuration of the intelligent cubicle controller 25.

As shown in the figure, the intelligent cubicle controller 25 is configured by connecting the CPU unit 37 to the communication unit 6 described above, and the CPU unit 37 includes the CRT 33, the switches 34, 36, and the lamp described above.
In addition to the printer 35, a printer 38, a database 39, and an external memory 40 are connected. The database 39 stores various kinds of knowledge for power control or power management. Memory 40
Stores various data including data detected from instruments.

The CPU unit 37 includes a demand control condition calculation unit 41,
It comprises a capacitor switching condition calculation unit 42, a power prediction unit 43, and a power management unit 44.

The power prediction unit 43 inputs a detection signal from the detector 5 such as an ammeter, a voltmeter, a power (valid / invalid) meter, and a thermometer,
Also, referring to the data input from the line-side data communication terminals 14 to 17 or the analysis results of the program, fuzzy inference is given as appropriate to predict the power (valid / invalid). When there is a possibility that the electric power may exceed the management target value of the demanded electric power, the demand control condition calculating unit 41 causes the demand controller 3 to perform a conditional operation.
And outputs information for reducing power to other data communication terminals 14 to 19 as appropriate. Further, the reactive power is output to the capacitor switching condition calculation unit 42, and the capacitor switching condition is calculated. As shown in FIG. 6, the power management unit 44 has processing units 45 to 51, and records line operation status, distribution load recording, distribution line open / close control, failure diagnosis, line communication, and incidental Performs various power management such as equipment control and maintenance records.

FIG. 7 is a block diagram showing a configuration example of the data communication terminals 14 to 17 on the line side.

As shown, the line-side data communication terminals 14 to
17, a reception data program analysis unit 52 and a communication data program generation unit 53 connected to the communication unit 10,
A power control condition calculation unit 54 connected to the analysis unit 52 and the generation unit 53, a line condition setting unit 55 and a switch control unit 56 corresponding to the device control unit 22 described above are provided.

The power control condition calculation unit 54 receives a signal from the line condition input unit 57,
For example, by inputting the current and future operation schedule of each machine by communicating with the main controller 27 of the LAN 23, converting this into data, and notifying the content to the management-side data communication terminal 25 via the communication unit 10, When a command is received from the intelligent cubicle controller 25, a calculation for predetermined power control is performed in cooperation with the main controller 27 of the LAN 23, and the operation conditions of each machine and the The NC program or schedule change command is set, and the switch 20 for each load is controlled to open and close via the switching control unit 56 at an appropriate timing.

FIG. 8 shows an outline of a process mainly performed by the power prediction unit 29 of the intelligent cubicle controller 25.

In step 801, the load is monitored in accordance with the detection signal of the detector 5, and in step 802, the power schedule of each unit is received from the data communication terminals 14 to 17 on the line side.
At 803, the received power is predicted.

This power forecast does not simply extend the current demand power and estimates the future power, but predicts the future demand power from the scheduled demand power of each machine. Become. For example, 10 minutes after the current time
Since you can know that the 30KVA motor starts rotating,
Minutes, valid and reactive power predictions can be made accurately. Further, the power prediction unit 43 includes a fuzzy inference unit, and refers to the knowledge database 39 to estimate the interlocking relationship of various devices accompanying the rough power schedule on the line side according to the rough power schedule. It is possible to make an accurate power prediction.

Therefore, in steps 804 to 806, the predicted power is compared with the management target value, and when the predicted power is likely to exceed the target value, power control in three stages is performed in step 804 and thereafter.

The first-stage power control is of the type that can most easily reduce power demand, including changing the operation timing of the load, changing the processing schedule, and controlling the load that is completely unrelated to processing. And interruption.

In the first-stage power control, the intelligent cubicle controller 25 asks the data communication terminals 14 to 17 on the line side whether or not the first-stage power control is possible, and obtains the answer. From cubicle controller 25 to demand controller 3,
Alternatively, it is executed by outputting a command to the other data communication terminals 14 to 19.

Examples of the change of the operation timing of the load executed on the line side include, for example, an example in which the operation start time of the machine with a certain load amount is slightly shifted from the time zone in which the peak power occurs,
There is an example in which the execution order of the machines A and B is reversed.

For example, punch press machines 31 arranged in series on a line
When punching is specified next to laser processing for A and the laser processing machine 31C, punching is executed first prior to laser processing. The reason is that, as shown in FIGS. 9 and 10, laser processing generally requires more power than punch processing. FIG. 9 shows the power characteristics of the punch press 31A, and FIG. 10 shows the power characteristics of the combined punch / laser machine 31B. As shown in FIG. 10, laser processing requires an electric power of 10 KW or more according to the start of processing.

Unnecessary loads are cut off via the line-side power control terminals 14 to 19 without using the demand controller 3 shown in FIG. 2 because the demand control power wiring 10 is The reason for this is that the wiring work is difficult and it is easier to manage the load on the line side on the line side even though the power is small. Further, in this example, since unnecessary loads can be cut off via the power control terminals 18 and 19 having no data processing unit 21, remote control can be performed by the management-side data communication terminal 25. In short, the first
The power control of the stage is a type in which the power peak can be easily shifted and the required power can be suppressed without affecting the processing at all.

The schedule change is made by the main controller 27 of LAN23.
Can be done automatically. Also, the machining program can be easily changed by the automatic programming device 28. The data processing units 21 of the line-side data communication terminals 14 to 17 may appropriately change the timing and the order by appropriately cooperating with the control device of the connected processing machine.

When the control state of the load is changed, the operating state of the auxiliary equipment such as a compressor may need to be changed in accordance with the changed state.In such a case, in this example,
Since a data communication terminal is interposed for each load, power can be easily supplied to the required compressor and power can be turned off to unnecessary compressors.

FIGS. 1 and 11 to 14 are explanatory diagrams showing specific examples of the procedure for changing the production schedule. Figure 11 shows the intelligent
Flow chart showing the transmission / reception state of the cubicle controller (ICC) and the main controller (IMC) of the LAN,
FIG. 1 is a flowchart showing a procedure for changing a production schedule of a main controller, FIG. 12 is an explanatory view of a power prediction chart displayed on a screen of the main controller, and FIGS. 13 and 14 are explanatory views of a schedule change screen. is there.

In Fig. 11, the intelligent cubicle
The controller 25 receives the production schedule from the main controller 27 (steps 1101 and 1105), and calculates a power prediction in step 1102. The calculation result is transmitted to the main controller 27 so that the main controller 27 can refer to the result at any time (step 1106).

Then, in step 1103, the intelligent cubicle controller 25 changes the predicted power P to the management target value P ₀
If there is a possibility that P ₀ ≦ P, a power schedule change command is output in step 1104 in this state without immediately shifting to normal demand control. This command is received on the main controller 27 side of the LAN 23 (step 1007), and in step 1108 a procedure for changing the production schedule is taken.

FIG. 1 shows a procedure for changing the production schedule performed by the main controller 27.

When the change request lamp for the production schedule is turned on in step 101, the operator sees this and turns on the power key in step 102.

Then, in step 103, as shown in FIG.
Displays a power prediction chart.

In the screen 58 shown in FIG. 12, the horizontal axis represents time, and the vertical axis represents predicted power P. It is assumed that the current time is 10:00.

In the chart of Fig. 12, 11 of the lines managed by LAN23
Due to the peak power from hour to 11:30, time 11
Receiving power over the 11:30 since it has been shown that it may exceed the management target value P _0.

Therefore, when the operator gives an operation command in step 104, the change plan of the production schedule is automatically calculated in step 105, and the first and second change plans are changed in step 105 as shown in FIG. 13 and FIG. Is displayed.

13 shows that the schedule A scheduled from 11:00 to 11:30 on the line should be advanced from 10:00 to 10:30 and executed. It is also shown that by executing the schedule A earlier, the demand power P from 11:00 to 11:30 can be suppressed to the management target value P ₀ or less.

The proposed change in FIG. 14 is that the schedule S1, which is a combination of the NC programs A, B, and C on the line i, is changed to another schedule S2 by changing the execution order of the NC programs, and the execution time of the NC program B with large power demand is changed. There are those reception power P to avoid coming between 11:30 o'clock 11 to avoid exceeding the management target value P _0.

The operator can change the production schedule by referring to the change plan in FIG. 13 or FIG. 14 and adopting the plan that can be adopted in step 1106. In step 1107, a change plan can be manually input.

Next, in Step 108, a change plan is created in accordance with the input contents of Step 106 or Step 107, and Step 1 is executed.
The change proposal created in 09 is transmitted to the intelligent cubicle controller 25.

Intelligent cubicle controller 25
Receives the transmission content from the main controller 27 in step 109 in FIG. 1 in step 1101 in FIG.
In step 1102, while calculating a new power prediction, the steps in FIG.
The power control shown below is performed.

In this way, the intelligent cubicle controller 25 not only communicates with the main controller 27 of the LAN 23, but also communicates with a controller that controls one or more machines via the other data communication terminals 15, 16, and 17, The operation timing of the machine located under the controller can be shifted and the program can be changed.

Referring again to FIG. 8, the second-stage power control in step 805 is a power control that is operated when the demand power is likely to exceed the target value even if the first-stage power control is performed.

In the second-stage power control, the demand controller 3 applies a power to a light load that is set in advance to be able to be cut off in the second stage.
Are operated in the same manner as in the conventional example, and predetermined loads connected to the demand control power wiring 12 are sequentially cut off. As the setting method of the cutoff sequence and the cutoff load, any of the conventional examples can be used.

However, in this example, the demand control condition calculation unit 41
It is important that the command controller 3 is operated under the conditions set here. That is, in the power control system of this example, the demand controller 3 is operated by the data communication terminals 25, 14 to 19 while emphasizing the power control on the line side. Since part of the load on the side can be cut off, the operating range of the demand controller 3 can be minimized accordingly.

The third-stage power control in step 806 is a control that is activated when the demand power is likely to exceed the target value even when the second-stage power control is performed.

In the third-stage power control, in addition to the lamp load set in advance to be able to be cut off in the third stage, the processing is slightly affected within a preset range, but the demand is improved by receiving the assistance of the line-side power control. The power can be suppressed below the target value.

Examples of this include the above-described schedule change and program change, but they are more sophisticated than those of the first and second cuts.

For example, in the processing of a product, control is performed such that the machine is temporarily stopped so that the processing of the product is delayed within a range in time for delivery. For this purpose, it is sufficient that the delay time for the completion of the product can be set at the site where the product processing is performed, based on the judgment of the operator. For this purpose, a process of temporarily stopping the machine is also performed, but the temporary stop here is the improved temporary stop described above, and no defective products are generated. In addition, as an extension, a method of turning daytime processing into unmanned processing at night is included.

As described above, due to the interconnection of the data communication terminals 25, 14 to 19, the peak value of the required power can be suppressed in a reasonable manner, and the required power can be suppressed to the target value or less.

Next, in the reactive power prediction process of step 807, the reactive power is predicted by the power predicting unit 43 according to the machine operation status on the line side, and the capacitor switching is performed by the capacitor switching condition calculating unit 42 according to the predicted reactive power. The condition is calculated and the switching of the capacitor is controlled.

 FIG. 15 is an explanatory diagram showing a reactive power prediction method.

In the figure, the time T ₁ when to time T ₁ is a reactive power Q ₀
From certain machine is operated, the reactive power is △ if Q only increases the prediction reactive power at time T ₁ after becomes Q ₀ + △ Q. This is the most basic idea, but △ Q can be determined as a function of time. In addition, the reactive power of the attached equipment can be accurately obtained. Another example of an operation schedule includes a schedule in which the machine stops after a certain period of time. In this case, it is generally expected that the reactive power will decrease after a certain period of time. Further, even for a portion where a scheduled operation cannot be notified, a more approximate value can be fuzzy inferred using a knowledge database as appropriate.

In the power factor improvement of this example, the reactive power can be accurately obtained according to the operation schedule of the machine, so that the capacitor can be turned on or off appropriately, the line current of the power receiving equipment is minimized, and The voltage can be maintained at a predetermined value, and high-quality power can be supplied to the production line.

[Effects of the Invention] As described above, the present invention provides a power control data communication terminal of a power receiving and distribution facility, a power control data communication terminal of a power load device including a plurality of metal working machines, and a power control device. In addition to being able to communicate with the power control data communication terminal of the management equipment managed by the operator via the power control communication network, data communication is also possible with the processing machine network composed of each metal processing machine. Therefore, the data communication terminal of the management device calculates the power prediction based on the processing schedule of each metal processing machine transmitted from the processing machine network, and when the predicted power value is likely to exceed the management target value, the power schedule is calculated. While the change command can be output, the processing machine network receives the power schedule change command to advance the machining schedule. Or, by changing the execution order, the processing schedule can be reconfigured, and a new processing schedule can be transmitted to the data communication terminal of the management device. As a result, the power receiving and distribution equipment and the metal processing line can be coordinated. Thus, there is an effect that the power demand of the entire metalworking line can be accurately controlled to be equal to or less than the management target value without lowering the production efficiency.

[Brief description of the drawings]

FIG. 1 is a flowchart showing a conversion method to be produced according to a main part of a power control system of a production line according to the present invention, FIG. 2 is a block diagram showing a factory power receiving and distribution system embodying the present invention, and FIG. FIG. 4 is an explanatory view showing an example of a local area network system (LAN) of a factory, FIG. 4 is a perspective view showing an external appearance of an intelligent cubicle controller, FIG. 5 is a block diagram showing an internal configuration thereof, and FIG. FIG. 7 is a block diagram showing a task configuration of the unit, FIG. 7 is a block diagram showing details of a data communication terminal arranged for a load group on the line side, FIG. 8 is a flowchart showing an example of a power control method, FIG. Is an explanatory diagram showing an example of power characteristics of a punch press machine, FIG. 10 is an explanatory diagram showing an example of power characteristics of a punch / laser combined machine, and FIG. -Vehicle. Controller (ICC)
And FIG. 12 is a flowchart showing a transmission / reception state of the main controller (IMC) of the LAN and FIG.
FIG. 15 is an explanatory diagram of a schedule change screen, and FIG. 15 is an explanatory diagram showing a reactive power prediction method. 1 Power receiving and distribution equipment 2 Intelligent cubicle controller 3 Demand controller 4 Capacitor bank 11 Data communication terminal on the cubicle 12 Demand control roll power wiring 13 Non-control power wiring 25 Management-side data communication terminal (intelligent cubicle controller) 43 Power forecasting unit 44 Power management unit

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-265428 (JP, A) JP-A-2-65626 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02J 3/00-5/00 H04L 12/28-12/44

Claims (1)

(57) [Claims] 1. A metalworking line provided with a power load device including a plurality of metalworking machines supplied with power from a predetermined power receiving / distributing facility, wherein the power receiving / distributing facility is provided with data communication for power control of the power receiving / distributing facility. While providing a terminal, each of the power load devices is provided with a power control data communication terminal of the power load device, and a power control data communication terminal is provided on a management device managed by an operator of each of the power load devices. The data communication terminals are connected to each other to form a power control communication network, and the communication network is connected to a processing machine network including the metal processing machines so that data communication is possible. Power to the data communication terminal based on the processing schedule of each metal processing machine transmitted from the processing machine network. Calculating the measured power, and when the predicted power value is likely to exceed the management target value, while providing a means for outputting a power schedule change command, the processing machine network receives the power schedule change command, A demand power control device for a metalworking line, comprising means for resetting a machining schedule by performing advancing or changing an execution order and transmitting a new machining schedule to a data communication terminal of the management device.