JPS60245428A - Maximum demand power monitor controller - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a maximum power demand monitoring and control device that monitors and controls the maximum power demand contracted by an electric power consumer to a power supply company.

[Prior art]

Generally, electric power consumers monitor the maximum demand power contracted with the power supply company, that is, the contracted power, and adjust the load so as not to exceed the contracted power. In other words, if the customer's load capacity exceeds the contracted power, operating the full load will cause the power consumption to exceed, so it is necessary to shut off some of the load that can be shut off at the point where there is a risk of exceeding the power consumption. As a result, the power consumption was kept within the contracted power.

One way to do this is to decide in advance the value at which the load is to be cut off, and then at regular intervals (for example, every 80 seconds), compare the current demand power with the value at which the load is cut off, and if the demand power exceeds that value, A load cutoff command was being output.

However, since this cutoff command is output based on the above comparison result, the load will be cut off immediately as soon as it exceeds the limit, and if another load stops immediately after that, the load that does not need to be cut off will be cut off. There was a drawback.

[Summary of the invention]

This invention was made in order to eliminate the above-mentioned drawbacks of the conventional ones, and it does not require pre-operation.

Compare the state of the load that can be predicted to stop with the shedding command, and if the load is expected to stop, make a decision such as postponing load shedding, and then cut off the load that does not need to be cut off. The object of the present invention is to provide a maximum power demand monitoring and control device that prevents

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure is a block diagram showing an embodiment of the maximum demand power monitoring and control device according to the present invention. In Fig. 1, the first input terminal (1) is inputted with an electric energy pulse generated for each unit of electric energy used, and the electric energy pulse generated for each unit of electric energy used is inputted to the first integration circuit (). This is to calculate the unit power Δp. A time pulse signal generated every unit time is input to the second input terminal (4), and the third integration circuit (5
), the unit time Δt is integrated. First arithmetic circuit (6
) is the unit power △p of the output of the second integration circuit 13) and the third
The unit average power Wt-ΔP/Δt at time t is calculated from the integration circuit + unit time Δt of the output of 51. A desired maximum power demand value, that is, a target power demand Q is set and input to the third input terminal (7). The fourth input terminal (8) is used to set and input the load capacity to be cut off. The fifth input terminal (
9) is where the state of the load to be cut off is input.

The second arithmetic circuit UO+ includes the unit average power Wt of the output of the first arithmetic circuit (6), the demand power value of the output of the first integration circuit (2), and the time from the second input terminal (4). The target power demand Q from the input terminal (7) of the pulse signal set 3 and the load capacity to be cut off from the fourth input terminal (8) are input, and the predicted power demand R at the end of the demand period is calculated. . The first display +II) displays the predicted power demand R calculated by the second calculation circuit σ■. The third arithmetic circuit 121 receives the predicted power demand R from the second arithmetic circuit, the target power demand Q from the third input terminal (7), and the breaking load capacity from the fifth input terminal (9). , when the excess of the predicted power demand R over the target power demand Q exceeds the cutoff load capacity, the output terminal 11 suddenly outputs a load cutoff command. The fourth arithmetic circuit 0 receives the unit time pulse from the second input terminal (4) and calculates the remaining time Tr until the end of the demand time period.

The second display US+ is for displaying the remaining time Tr calculated by the fourth calculation circuit (141).

Next, the operation of the present invention will be explained using FIG. 2.

In FIG. 2(a), the first integration circuit (2) is now connected to the first integration circuit (2).
The power pulses from the input terminal (1) are integrated,
Assuming that the current power demand at any time t1 within the demand time period is P (point A), the predicted power demand R calculated by the second calculation circuit uO) at this point A is R = P + S. Story-(1-1
, ) (0 points), this predicted power demand R is input from the third input terminal (7) and exceeds the target power demand Q,
This difference is calculated by the third calculation circuit (1), and if it exceeds the breaking load capacity, an output is generated at the output terminal and the load must be broken. However, as shown in Figure 2 (b), If the load W1, whose operation and stoppage can be predicted, stops from time t2 to time t8 within the demand time limit, the predicted power demand R1 calculated by the second calculation circuit σα at this point A is as follows. 01 point), this predicted power demand R1 is lower than the target power demand Q, so there is no need to cut off the load.Therefore, there is no need to cut off and turn on loads that do not need to be cut off, which is a wasteful operation. It will no longer occur.

Next, the opposite case will be explained using FIG. Figure 3(a)
Similarly, the predicted power demand R at point A of
1,) (0 points), and this predicted power demand R is the target power demand Q
When the difference exceeds the cut-off (turn-on) load capacity, the load can be turned on.

However, the load W1, whose operation can be predicted to stop in advance, stops from time t2 to time t8 within the demand time limit,
And if it is currently stopped, then it is different (C
3) Since this predicted power demand R7 approaches the target demand power saving Q, the load cannot be applied. Therefore, the wasteful operation of turning on a load that should not be turned on and immediately cutting it off again will not occur.

Note that if an arithmetic device such as a microcomputer is used, the circuit configuration shown in FIG. 1 can be simplified, and calculations can be easily performed.

〔Effect of the invention〕

As described above, according to the present invention, there is no need to turn on and immediately cut off again when performing load control, or to exceed the cut off load and then turn on again, and there is no inconvenience in terms of safety and operation. This has the effect of making it possible to make maximum use of electricity within the contract.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the maximum demand power monitoring and control device according to the present invention, and FIGS. 2 and 3 are diagrams illustrating the operation of the present invention. In the figure, (1) is the first input terminal, (2) is the first integration circuit, (3) is the second integration circuit, (4) is the second input terminal, and (5) is the third integration circuit. Integration circuit, (6) is the first calculation circuit K (7) is the third input terminal, (8) is the fourth input terminal,
(9) is the fifth input terminal, Uα is the second arithmetic circuit, (1
1) is the first display, 1121 is the third arithmetic circuit, information is the output terminal, (141 is the fourth arithmetic circuit, [151 is the second
This is an indicator. Agent: Masuo Oiwa, Patent Attorney Figure 1 Figure 2 (0)

Claims (1)

[Claims] (1) Maximum demand power monitoring and control equipment that monitors and controls the maximum power demand of all loads, which have loads that can be shut off (loads that can be cut off) and loads that can be predicted to start or stop in advance, to below the contract power. means for calculating the current power and the average power per unit time; means for calculating the predicted power demand from the current power, the average power and the remaining time; A maximum power demand monitoring and control device characterized by comprising means for calculating predicted power demand corrected based on the state of the load being applied.