JPS5914327A - Load control system for demand power monitor - 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 The present invention relates to a load control method for a power demand monitoring device, and more particularly, the present invention relates to a load control method for a power demand monitoring device, and in particular, the power demand monitoring device, which monitors the amount of demand power supplied to the load side, controls the power demand to be determined in advance. The present invention relates to a load control method for a power demand monitoring device suitable for controlling the supply of power to a load so as not to exceed a contracted power which is a set power.

In places such as factories that use a large amount of electricity, a contract is made with the power company for the amount of electricity used for a certain period of time, for example 30 minutes, and if the amount of electricity used within a certain period of time exceeds the contracted amount, a penalty fee will be charged. I'm trying to pay the company. Therefore, 30
When a contract is made for the amount of power used per minute, as shown in Figure 1, the available power PI for the next 15 minutes T2 is calculated from the actual power used for the past 15 minutes TI and the contracted power P, and the current received power is The conventional method is to shut off a preset load when the power PR is high, and then turn on the cut-off load again when there is sufficient available power.

In the case of this method, control is performed to turn on, cut off, and turn on the load based on the actual power used up to half of a certain period of time, regardless of the power demand on the load side.

Therefore, if there is only one with a large load capacity to interrupt,
There were problems in that the load was repeatedly turned on and off, and the amount of electricity used within a certain period of time was less than the contracted electricity, making it impossible to effectively supply electricity to the load. .

The present invention has been made in view of the above-mentioned problems, and its object is to provide a power demand monitoring device that can reduce load shedding without the amount of power used within a certain period of time exceeding a predetermined set power. The object of the present invention is to provide a load control method.

In order to achieve the above object, the present invention provides a power demand system that counts the amount of power supplied to the load, monitors the power demand on the load side based on the counted value, and controls the supply of power to the load. In the load control method of the monitoring device, it is predicted whether or not the 'M required power on the load side will exceed a predetermined set power based on the amount of power supplied to the load side, and the predicted power will exceed the set power. If there is a risk that a predetermined load will be cut off, the power demand will be predicted when a predetermined load is cut off, and only if the predicted power exceeds a value that is smaller than the set power, the predetermined power will be set. It is characterized in that the load is cut off when the load is turned off, and the load is not cut off at other times.

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

FIG. 2 shows a block diagram of a preferred embodiment of the present invention. In the figure, power supplied to a load 2 is detected by a power detector 4, and is supplied to a power demand monitoring device 6 as a pulse signal corresponding to the power. The power demand monitoring device 6 counts the amount of power supplied to the load 2 based on the pulse signal, predicts whether the power demand of the load 2 will exceed the contract power which is a predetermined set power, and A control signal for controlling the supply of power to the load 2 based on the power supply controller 8 is supplied to the power supply controller 8.

In this embodiment, in order to prevent the demand forecast from changing significantly depending on the power amount monitoring timing, when the fixed time is set to 30 minutes, the power demand monitoring device 6 is set as shown in FIG. Demand forecasting based on the supplied pulse signal A is started at times a and b, 15 minutes after the start of monitoring.
, c, and d.

Next, the effect when the fixed time is 30 minutes will be explained based on chart 70 in FIG.

First, in step 100, after starting power demand monitoring,
A determination is made as to whether or not the minute has elapsed. NO at this step
If it is determined that
If it is determined to be ES, the process moves to step 102. In step 102, the average power is calculated based on the integrated power amount from the start of monitoring to the present time, and this value is multiplied by the remaining time to predict the power amount at the end of monitoring. After that, the process moves to step 104, and it is determined whether the predicted power amount exceeds the contracted power as the set power. If it is determined as YES in this step, the process moves to step 106, and from the predicted electric power amount, subtract the value obtained by multiplying the cant electric power when the predetermined load is cut off by the remaining time, and this value is calculated as the contracted electric power. Judgment is made based on whether or not it exceeds. Note that in this case, power α as a certain margin is added to the predicted power amount. In this step 1Y-
If it is determined as EYES, proceed to step 108;
Cut off a predetermined load. If the determination in step 106 is NO, the load is not cut off and the process moves to the next step.

If the determination in step 104 is NO, the process moves to step 110, where it is determined whether there is a load whose peak has been cut. If the determination in this step is YES, the process moves to step 112, and it is determined whether or not it is possible to apply the peak-cut load. This determination determines whether the sum of the power amount obtained by multiplying the power remaining by the remaining time when the peak-cut load is applied, the predicted power amount, and the power α as a margin exceeds the contract power. If the determination in this step is NO, the process moves to step 114 and the load that has been peak-canted is re-applied.

In this example, the power demand is accumulated in 30-minute increments from the monitoring start time, and load control is performed so that the power demand does not exceed the contract power at the time the monitoring ends. can be prevented.

Furthermore, in this embodiment, even if the predicted power amount P1 at the time when 15 minutes have elapsed from the start of monitoring as shown in FIG. If the demand power decreases as shown by the dashed line, there will be no need to cut off the load.
Load shedding can be reduced.

As explained above, according to the present invention, even if it is determined that it is necessary to shear a load and there is no need to shelve a heavy load, it may not be necessary to shelve a heavy load by delaying the timing of load shedding. Blockage can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining the conventional system, FIG. 2 is a configuration diagram showing an embodiment of the present invention, FIG. 3 is an explanatory diagram of the operation of the device shown in FIG. 2, and FIG. FIG. 5 is a flowchart for explaining the operation of the present invention, and FIG. 5 is a diagram showing the relationship between electric power amount and monitoring timing. 2... Load, 4... Power detector, 6... Power demand monitoring device, 8... Power supply controller. Station! η Prefectural opening□

Claims (1)

[Claims] 1. In the load control method of the power demand monitoring device, which counts the amount of power supplied to the load, monitors the power demand on the load side based on the counted value, and controls the supply of power to the load.
Predicting whether the power demand on the load side will exceed a predetermined set power based on the amount of power supplied to the load side,
When there is a possibility that the predicted power will exceed the set power, the power demand when a predetermined load is cut off is predicted, and the predicted power at this time is set to a value smaller than the set power. 1. A load control method for a power demand monitoring device, characterized in that a predetermined load is cut off only when the load is exceeded, and the load is not cut off at other times.