JP2021114809A - Power demand control method, power demand control device, and program - Google Patents

Abstract

To provide a power demand control method capable of improving the prediction accuracy of a demand prediction value, and a technology related thereto.SOLUTION: On the basis of first actual power consumption Pa used by a first power consumption facility, a first demand predicted value of the first power consumption facility is obtained. In addition, on the basis of second actual power consumption Pb used by a second power consumption facility, and predicted rolling power Qm proportional to the rolling volume flow rate which is the product of the rolling reduction of a steel sheet rolled in a rolling process, the width of the steel sheet, and the rolling speed of the steel sheet, a second demand predicted value of the second power consumption facility is obtained. Then, power supply to the predetermined power consumption facility from among a plurality of power consumption facilities is controlled such that the sum of the first demand predicted value and the second demand predicted value is less than contract power and is as close as possible to the contract power.SELECTED DRAWING: Figure 2

Description

The present invention relates to a power demand control method for controlling power supply to a plurality of power consuming facilities, and a technique related thereto.

For example, for electric power consumers equipped with multiple power consumption facilities such as steel mills or steel mills, contracted power within a predetermined demand cycle is agreed upon in partnership with an electric power company, and the maximum is in the factory. A demand power meter (demand meter) is provided.

For example, in Patent Document 1, a plurality of power consumption facilities are divided into a first power consumption facility and a second power consumption facility so that the total power consumption measured by the demand meter does not exceed the contract power, and both of them are used. Demand predicted values are obtained respectively, and the power supply to the power consuming equipment is controlled so that the sum of both demand predicted values is less than the contracted power and is as close as possible to the contracted power.

Japanese Unexamined Patent Publication No. 6-284572

However, there is room for improvement in the technique described in Patent Document 1 regarding the prediction accuracy of the demand prediction value.

Therefore, an object of the present invention is to provide a power demand control method capable of improving the prediction accuracy of a demand prediction value, and a technique related thereto.

(1) The first power consumption facility whose power consumption increases substantially in proportion to the passage of time and the rolling process are performed, and the rolling power amount, which is the power used for the rolling process, is a load according to the rolling conditions. A power demand control method for controlling power supply to a plurality of power consumption facilities including a second power consumption facility that varies depending on the above, and is a first power demand control method used by the first power consumption facility within a predetermined demand cycle. Based on the actual power consumption, the first demand predicted value of the first power consumption facility is obtained, the second actual power consumption used by the second power consumption facility within a predetermined demand cycle, and the rolling process. Second demand prediction of the second power consumption facility based on the predicted rolling electric energy proportional to the reduced volume flow rate, which is the product of the rolling amount of the steel plate rolled in, the width of the steel plate, and the rolling speed of the steel plate. A value is obtained, and the sum of the first demand predicted value and the second demand predicted value is predetermined among the plurality of power consuming facilities so as to be less than the contracted power and as close as possible to the contracted power. A power demand control method characterized by controlling the power supplied to power consuming equipment.

(2) The first power consumption facility whose power consumption increases substantially in proportion to the passage of time and the rolling process are performed, and the rolling power amount, which is the power used for the rolling process, is a load according to the rolling conditions. A power demand control device that controls power supply to a plurality of power consumption facilities including a second power consumption facility that fluctuates according to the above, and is a first power demand control device used by the first power consumption facility within a predetermined demand cycle. The first calculation means for obtaining the first demand predicted value of the first power consumption facility based on the actual power consumption, and the second actual power consumption used by the second power consumption facility within a predetermined demand cycle. The second power consumption facility is based on the predicted rolling electric energy proportional to the reduced volume flow rate, which is the product of the reduction amount of the steel plate rolled in the rolling process, the width of the steel plate, and the rolling speed of the steel plate. The sum of the first demand predicted value and the second demand predicted value is less than the contracted power and is as close as possible to the contracted power. A power demand control device including a demand control means capable of controlling power supply to a predetermined power consumption facility among a plurality of power consumption facilities.

(3) The first power consumption facility whose power consumption increases substantially in proportion to the passage of time and the rolling process are performed, and the rolling power amount, which is the power used for the rolling process, is a load according to the rolling conditions. A computer built in a power demand control device that controls power supply to a plurality of power consumption facilities including a second power consumption facility that varies depending on a) a) by the first power consumption facility within a predetermined demand cycle. A step of obtaining a first demand predicted value of the first power consuming equipment based on the first actual electric energy used, and b) a second used by the second power consuming equipment within a predetermined demand cycle. Based on the actual power consumption, the predicted rolling power amount proportional to the reduction volume flow rate, which is the product of the reduction amount of the steel plate rolled in the rolling process, the width of the steel plate, and the rolling speed of the steel plate, the first 2 The step of obtaining the second demand predicted value of the power consuming equipment and c) the sum of the first demand predicted value and the second demand predicted value is less than the contracted power and is as close as possible to the contracted power. A program for executing a step of controlling the power supply to a predetermined power consumption facility among the plurality of power consumption facilities.

The number of the first power consumption equipments described in the above (1) to (3) may be one or a plurality. Similarly, the second power consumption equipment described in (1) to (3) above may be one or a plurality of them.

According to the invention of the present application, it is possible to improve the prediction accuracy of the demand prediction value.

It is a system diagram of the demand control device which concerns on one Example of this invention. It is a graph which shows the actual power, the predicted power, and the like.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a system diagram of a demand control device 1 according to an embodiment of the present invention.

For example, in a cold rolling plant, a plurality of electric powers including a small power consumption facility 11 that can operate with less than a certain amount of electric power and a large power consumption facility 12 that uses a large amount of electric power (more than a certain amount of electric power). The consumption facility 10 is provided. Examples of the low power consumption equipment 11 include various process lines and ancillary equipment, and examples of the high power consumption equipment 12 include rolling equipment.

Here, it is assumed that the amount of electric power used by the low power consumption equipment 11 increases substantially in proportion to the passage of time.

The rolling equipment 12 is equipment for rolling a steel sheet. The amount of electric power used for the rolling process in the rolling equipment 12 varies (changes) depending on the load according to the rolling conditions (thickness H, width B and / or rolling speed V, etc. of the steel sheet to be rolled). The amount of electric power used in the rolling process is also referred to as the amount of rolling electric power.

The electric power supplied from the electric power company via the distribution line is given to the receiving end 2, and the electric power from the receiving end 2 is transformed by a transformer (not shown) through the transformer for trading instrument 3 and consumes a small amount of electric power. Power is supplied (supplied) to the equipment 11 and the rolling equipment 12 and the like.

A circuit breaker 4 is interposed between the power receiving end 2 and the transaction instrument transformer 3, and a transaction instrument (WHM) 5 is connected to the transaction instrument transformer 3. Then, the total power consumption of each power consumption facility 10 is obtained (acquired) by the transaction instrument 5.

The trading instrument 5 is provided with a pulse transmitter that converts the total power consumption into, for example, 10 kWH (kilowatt hour) / pulse pulse signal, and the pulse signal corresponding to the total power consumption is transmitted to the demand control means 9. Entered. Further, the electric power used by the rolling equipment 12 and the low power consumption equipment 11 is detected as a change in electric energy by the watt hour meter 6 with a pulse transmitter and is given (input) to the demand control means 9.

Further, the power used by the rolling equipment 12 is given to the signal processing means 7 realized by a process computer or the like for signal processing, and the related information related to the amount of power used from the signal processing means 7 is the demand control means 9. Given to. The related information includes, for example, the coil number of the steel sheet rolled by the rolling equipment 12, the rolling time TM, the rolling electric energy Qm and / or the stop time and the like.

In this way, the power consumption (kWH) of the rolling equipment 12 and the power consumption of the low power consumption equipment 11 are input (acquired) to the demand control means 9, respectively.

As will be described later, the demand control means 9 is based on the actual power consumption (actual value of the power consumption) Pa used by the low power consumption equipment 11 within a predetermined demand cycle DP (here, a 30-minute cycle). Then, the predicted demand value Ra (kW (kilowatt)) of the low power consumption equipment 11 is obtained. Further, the demand control means 9 obtains a demand predicted value Rb (kW) of the rolling equipment 12 based on the actual power consumption Pb or the like used by the rolling equipment 12 within the predetermined demand period DP. Here, it is assumed that the demand control means 9 also functions as a calculation means for obtaining each demand predicted value Ra, Rb.

Then, the demand control means 9 has a plurality of power consumption facilities 10 so that the sum R (= Ra + Rb) of the predicted demand values Ra and Rb is less than the contract power (kW) and is as close as possible to the contract power. Of these, the power supplied to the predetermined power consumption equipment is controlled. For example, the demand control means 9 operates an alarm device 8 (buzzer, alarm lamp, etc.) when the demand prediction value R exceeds the target value, which is a value several percent (for example, 3%) lower than the contracted power. The operator (operator) is made to reduce the rolling speed V of the steel sheet in the rolling equipment 12.

A computer (computer system) equipped with a CPU or the like is built in the power demand control device 1, and a processing unit such as the demand control means 9 is realized by executing a predetermined software program on the computer. Will be done.

Next, a method of calculating the demand predicted value R (= Ra + Rb) and the like will be described with reference to FIG.

In FIG.
T0 is the start time of the predetermined demand cycle DP,
T1 is the current time (here, the time when the welding point at the tip of the next coil reaches the position immediately before the rolling equipment 12),
T2 is the time after a predetermined time ΔT has elapsed from the time T1 (here, the estimated completion time of the rolling process of the next coil).
TE is the end time of the predetermined demand cycle DP,
Pa is the actual amount of power used by the low power consumption facility 11 (between time T0 and time T1) at time T1 in the demand cycle DP.
Pb is the actual amount of power used by the rolling equipment 12 at time T1 within the demand cycle DP.
Qa is the estimated power consumption used by the low power consumption equipment 11 at time T2.
Qb is the estimated power consumption used by the rolling equipment 12 at time T2.
Qm1 is the predicted rolling power amount used for the rolling process in the rolling equipment 12 within the period ΔT from the time T1 to the time T2.
Pk is the contracted electric energy corresponding to the demand cycle DP (here, contracted electric energy / 2),
Qk is the target electric energy in the demand cycle DP (for example, 0.97 Pk),
Is shown.

First, the demand predicted value (final demand predicted value at the end time TE of the demand cycle DP) Ra of the low power consumption equipment 11 is calculated by the following equation (1).

The reason why the value "60 / DP" is multiplied by the value in parentheses on the right side of the equation (1) is to convert the power consumption (kWH) in the demand cycle DP into the power consumption (kW). Is. Here, since the demand cycle DP is 30 minutes, the numerical value in parentheses on the right side of the equation (1) is doubled (= 60/30).

Further, the demand predicted value (final demand predicted value) Rb of the rolling equipment 12 is calculated by the following formula (2).

Qm of the formula (2) is a predicted rolling electric energy (kWH) used by the rolling equipment 12 within the period (= TE-T2) from the current time T1 to the end time TE of the demand cycle DP.

Specifically, the predicted rolling power amount Qm is a plurality of coils (plural rolling) that are passed through the rolling equipment 12 between the current time T1 and the end time TE of the demand cycle DP (within the remaining time of the demand cycle DP). It is the total value of the predicted rolling power amount Qmi (i = 1, ..., n (n is the number of rolling target coils)) in the rolling process for each of the target coils).

The predicted rolling power amount Qmi for each coil is obtained as follows. Here, the predicted rolling power Qm1 for the first (i = 1) coil (next coil) after the current time T1 will be described.

First, the rolling time (expected rolling time) TM of the next coil is obtained by using the following formula (3). In the following formula (3), L is the output coil length of the next coil, and V is the rolling speed.

Next, the predicted rolling power amount (the amount of power predicted to be used for the rolling process of the next coil) Qm1 for the next coil is calculated by the following formula (4).

In the above equation (4), F is a reduced volume flow rate (described later), and M is a proportionality constant (described later).

The rolling volume flow rate F is the product (= ΔH) of the rolling amount ΔH of the steel sheet to be rolled in the rolling process, the width (length in the lateral direction) B of the steel sheet, and the rolling speed V of the steel sheet. It is calculated by × B × V). The reduction amount ΔH is the difference (= H2-H1) between the entry side thickness H1 and the exit side thickness H2 of the next coil, and is obtained by a predetermined reduction rate r.

Specifically, the product (ΔH × B) of the rolling reduction amount ΔH and the width B of the steel sheet to be rolled is the amount of change in the cross-sectional area of the steel sheet (the area of the cross section whose vertical line is the moving direction of the steel sheet) due to the rolling process. The reduced volume flow rate F of the steel sheet is the volume flow rate (ΔH × B × V) obtained by multiplying this change amount (ΔH × B) by the rolling speed V.

Since the steel sheet is rolled as a result of the power being supplied to the rolling equipment 12 (the cross-sectional area changes by the amount of reduction ΔH), the applicant of the present application has applied that the rolling volume flow rate F of the next coil is rolling per unit time. He devised the idea that it is proportional to the work of equipment 12 (that is, electric power (kW)). Then, by multiplying this by the rolling time TM obtained by the above formula (3), the predicted rolling power amount Qm1 (kWH) in the rolling process of the next coil can be obtained.

The proportionality constant M in the equation (4) is predetermined in the data table for each steel type and roll surface (for each combination of steel type and roll surface) based on experience. For example, when the next coil is the first steel type and the first roll surface, a predetermined proportionality constant M is used for the combination of the first steel type and the first roll surface in the data table.

In this way, the predicted rolling power Qm1 for the next coil is obtained based on the reduced volume flow rate F of the next coil.

Similarly, the predicted rolling power amount Qmi is obtained for the second (i = 2) and subsequent coils to be rolled after the current time T1.

Then, the total value Qm of the predicted rolling electric energy Qmi (i = 1, ..., N) in the rolling process for each of the plurality of rolling target coils is obtained, and the demand predicted value is obtained using the above equation (2). Rb is required.

As a result, the demand prediction value R (= Ra + Rb) can be obtained.

As described above, the demand predicted value Rb of the rolling equipment 12 is obtained based on the predicted rolling electric energy Qm proportional to the rolling volume flow rate F of the steel sheet rolled in the rolling process. Specifically, the rolling volume flow rate F is the product of the rolling amount ΔH of the steel sheet rolled in the rolling process, the width B, and the rolling speed V, and varies depending on the coil to be rolled (the steel type of the coil, etc.). Such a reduced volume flow rate F is obtained for each of the plurality of rolling target coils to be rolled after the current time T1, and the predicted rolling electric energy Qmi corresponding to each reduced volume flow rate F is obtained. Then, the demand predicted value Rb of the rolling equipment 12 is obtained based on the total value Qm. Therefore, it is possible to improve the prediction accuracy of the demand prediction value R.

According to the embodiments described above, the following inventions can be provided.

The power demand control method of the present invention
A first power consumption facility (for example, a small power consumption facility 11) whose power consumption increases substantially in proportion to the passage of time, and
A second power consumption facility (for example, rolling facility 12) in which the rolling process is performed and the rolling power amount, which is the amount of power used in the rolling process, fluctuates depending on the load according to the rolling conditions.
It is a power demand control method that controls the power supply to a plurality of power consumption facilities including.
Based on the first actual power consumption (for example, the actual power consumption Pa) used by the first power consumption equipment within a predetermined demand cycle, the first demand predicted value (for example, for example) of the first power consumption equipment. Demand predicted value Ra) is calculated,
The second actual power consumption (for example, the actual power consumption Pb) used by the second power consumption facility within a predetermined demand cycle, the rolling amount of the steel sheet rolled in the rolling process, and the width of the steel plate. The second power consumption facility is based on a predicted rolling electric energy (for example, a predicted rolling electric energy Qm) proportional to a reduced volume flow rate (for example, a reduced volume flow rate F), which is the product of the rolling speed of the steel plate. 2 Demand predicted value (for example, demand predicted value Rb) is obtained,
A predetermined power consumption facility among the plurality of power consumption facilities so that the sum of the first demand predicted value and the second demand predicted value is less than the contract power and is as close as possible to the contract power. It is characterized by controlling the power supply to.

Although the present invention is described in the above preferred embodiment, the present invention is not limited thereto. Various embodiments are possible that do not deviate from the spirit and scope of the invention.

1 Demand control device 10 Demand control means 11 Low power consumption equipment 12 Rolling equipment Pa Actual power consumption used by the low power consumption equipment at time T1 Pb Actual power consumption used by the rolling equipment at time T1 Contracted electric energy corresponding to the Pk demand cycle Qa Estimated electric energy used by the low power consumption equipment at time T2 Qb Estimated electric energy used by the rolling equipment at time T2 Qm1 From time T1 to time T2 Estimated rolling power used in the rolling equipment within the period ΔT of

Claims (3)

The first power consumption facility, whose power consumption increases approximately in proportion to the passage of time,
A second power consumption facility in which the rolling process is performed and the rolling power amount, which is the amount of power used in the rolling process, fluctuates depending on the load according to the rolling conditions.
It is a power demand control method that controls the power supply to a plurality of power consumption facilities including.
Based on the first actual electric energy used by the first power consuming equipment within a predetermined demand cycle, the first demand predicted value of the first power consuming equipment is obtained.
The product of the second actual power consumption used by the second power consumption facility within a predetermined demand cycle, the rolling amount of the steel sheet rolled in the rolling process, the width of the steel sheet, and the rolling speed of the steel sheet. The second demand predicted value of the second power consuming equipment is obtained based on the predicted rolling electric energy proportional to a certain rolling volume flow rate.
A predetermined power consumption facility among the plurality of power consumption facilities so that the sum of the first demand predicted value and the second demand predicted value is less than the contract power and is as close as possible to the contract power. A power demand control method characterized by controlling the power supplied to the power supply. The first power consumption facility, whose power consumption increases approximately in proportion to the passage of time,
A second power consumption facility in which the rolling process is performed and the rolling power amount, which is the amount of power used in the rolling process, fluctuates depending on the load according to the rolling conditions.
It is a power demand control device that controls the power supply to a plurality of power consumption facilities including
A first calculation means for obtaining a first demand predicted value of the first power consuming equipment based on the first actual electric energy used by the first power consuming equipment within a predetermined demand cycle.
The product of the second actual power consumption used by the second power consumption facility within a predetermined demand cycle, the rolling amount of the steel sheet rolled in the rolling process, the width of the steel sheet, and the rolling speed of the steel sheet. A second calculation means for obtaining a second demand predicted value of the second power consuming equipment based on a predicted rolling electric energy proportional to a certain rolling volume flow rate.
A predetermined power consumption facility among the plurality of power consumption facilities so that the sum of the first demand predicted value and the second demand predicted value is less than the contract power and is as close as possible to the contract power. Demand control means that can control the power supplied to
A power demand control device characterized by including. The first power consumption facility, whose power consumption increases approximately in proportion to the passage of time,
A second power consumption facility in which the rolling process is performed and the rolling power amount, which is the amount of power used in the rolling process, fluctuates depending on the load according to the rolling conditions.
In a computer built into a power demand controller that controls the power supply to multiple power consuming equipment, including
a) A step of obtaining a first demand predicted value of the first power consuming equipment based on the first actual electric energy used by the first power consuming equipment within a predetermined demand cycle.
b) The second actual power consumption used by the second power consumption facility within a predetermined demand cycle, the rolling amount of the steel sheet rolled in the rolling process, the width of the steel sheet, and the rolling speed of the steel sheet. The step of obtaining the second demand predicted value of the second power consuming equipment based on the predicted rolling electric energy proportional to the rolling reduction volume flow rate, which is the product, and
c) Predetermined power among the plurality of power consuming facilities so that the sum of the first demand predicted value and the second demand predicted value is less than the contract power and is as close as possible to the contract power. Steps to control the power supply to the consumption equipment,
A program to execute.

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