JPH0556698A - Demand prediction controller - Google Patents

Abstract

PURPOSE:To realize stable power supply by operating an optimal generator output correction amount every moment through fuzzy inference based on membership relations between time, ' temperature difference, and generator output correction amount and then controlling the system to follow up thus operated optimal amount. CONSTITUTION:At first, initial generator output predicting section of a knowledge base 10 prepares a generator output prediction curve based on past achievement data according to three types of basic patterns corresponding to Sunday, holiday and weekday. A fuzzy inference section 12 then determines a generator output curve ( MW) 13 through fuzzy inference based on the temperature detected at a temperature detecting section 11. A control section then performs generator output control according to a new output curve. According to the invention, power can be supplied stably.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power demand prediction control device for a thermal power plant or a nuclear power plant.

[0002]

2. Description of the Related Art Conventionally, with respect to generator output adjustment control of a thermal power plant or a nuclear power plant, a generator output adjustment command is sent from a central power supply station to each generator of each power plant. Each generator controls the generator output momentarily according to a command from the central power supply station. By the way, the power demand greatly changes depending on the temperature on the day of the day, especially in summer. When the temperature rises, the demand for coolers and the like will rapidly increase, and a command will be sent from the central power supply station to each power plant so as to rapidly increase the output of each generator.

This will be described with reference to FIG. Figure 8
A generator output curve (plan) 100 on the day and an actual generator output curve (actual result) 101 are shown.

A generator output curve (planned) 100 against a generator output curve (actual) 1 according to a change in temperature on the day
There is a command from the central power supply station for the output change request such as 01, and the generator output is made to follow the command value. The power station side has a predetermined 1 as much as possible
It will be possible to operate smoothly according to the generator output curve of the day, which enables safe operation.

[0005]

However, in each power station, it takes a considerable time to increase or decrease the output of the power station according to the generator output increase / decrease command from the central power supply station and adjust it to the required command value. In such a case, when each generator cannot immediately cope with output adjustment, the supply will be insufficient as a result of the power demand, and as a result, there is a risk of an accident such as a voltage drop of the transmission line or a power failure. It may occur. Further, for the operator, an increase in the amount of work, such as a change in the start schedule of the auxiliary equipment required to meet an unexpected change in the generator output, causes a complicated operation operation.

The present invention has been made to solve the above-mentioned conventional problems, and an object thereof is to eliminate the sudden power output change command from the central power feeding station to the generators of each power station, and It is an object of the present invention to provide a power demand prediction control method capable of supplying stable power by predicting power demand in advance by fuzzy reasoning according to the temperature and correcting the output of the generator.

[0007]

The present invention is a control device for controlling a generator output in a thermal power plant, a nuclear power plant, or the like, which calculates a temperature deviation between an air temperature on the day and an average temperature, and Is calculated by fuzzy reasoning from the function of the time and the temperature deviation, and the target value is the generator output obtained by adding this correction amount to the generator output scheduled curve. The output of the generator is controlled so as to follow.

[0008]

[Function] To determine a correction amount by using fuzzy inference with respect to a daily output prediction curve of a generator output in a thermal power plant or a nuclear power plant, and to make the generator output follow the predicted output value. Control.

[0009]

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

FIG. 1 is a configuration diagram for determining a daily generator output prediction curve to which the present invention is applied.

First, the initial generator output predicting section of the knowledge base 10 creates a generator output predicting curve for the current day from the data based on the past results according to three types of carrier patterns, that is, the current day is Sunday, a holiday or a weekday.

Next, the fuzzy reasoning unit 12 determines the generator output curve correction amount (ΔMW) 13 by fuzzy reasoning based on the temperature of the day of the temperature measuring unit 11.

Then, the control unit 14 controls the generator output with the new output curve as the target value.

As an example, FIG. 2 shows a daily output curve of a generator whose output can be adjusted. In FIG. 2, the vertical axis 21 represents the generator output (MW), the horizontal axis 22 represents the time, and 23 represents the generator output. Generally, since the usage amount is low at night, the generator output (MW) is low. Since there are many places for lunch break between 12:00 and 13:00, the generator output (MW) temporarily decreases.

Next, the fuzzy inference method in the fuzzy inference unit 12 of FIG. 1 will be described in detail below.

FIG. 3 shows the membership function of time.

Here, NB, NEGATIVE BIG NM, NEGATIVE MIDI MIDI NS, NEGATIVE SMALL Z, ZERO PB, POSITIVE BIG PM, POSITIVE MIDIUM PS, and POSITIVE SMALL, respectively.

That is, since the generator output is a function of time, when 12:30 in the daytime is Z, that is, when 0 is set to zero, 20:00 is positive and large (PB) in the positive direction, and 17:00 is positive and intermediate. (PM), 14:00 is positive and small (PS), 10 o'clock is negative and small (NS), 7 o'clock is negative and intermediate (NM), and 24:00 is negative and large (NB). ..

FIG. 4 shows the membership function with respect to the temperature deviation.

Here, α is a temperature deviation value and is arbitrarily determined. Z is zero, PS is positive and small, and NS is negative and small.

FIG. 5 shows the membership function of the generator output correction amount.

Here, β and γ are generator MW correction values, which are arbitrarily determined. Z is zero, PS is positive and small, PM
Is positive and intermediate, NS is negative and small, and NM is negative and intermediate.

[0023]

[Table 1]

Here, Table 1 is for determining the generator output curve correction amount MW based on time and temperature deviation.

FIG. 6 shows an example for determining the generator output correction amount MW from Table 1.

As an example, the procedure for determining the center of gravity of the composite function by the known MIN-MAX method for the portions of the symbols a, a, u, and d will be shown.

A will be described.

First, an intersection 710a with a triangle 710 is obtained on a dotted line 700 at a certain time T1. Next, regarding the temperature deviation, the intersection 7 of the dotted line 701 and the triangle 711
The smaller one of 10a and 711a is taken, and the triangle 712 is truncated.

Similar operations are carried out for a, c and d, and the triangles 722, 732 and 742 are respectively truncated.

These triangles 712, 722, 732, 7
FIG. 7 shows a diagram in which 42 is synthesized. In FIG. 7, X represents the center of gravity.

In FIG. 7, triangles 712, 722, 732 and
Choose the larger of 742.

Next, the center of gravity of the composite function of FIG. 7 is calculated, and the result is set as MW to obtain the generator output correction amount MW at a certain time T1. This corresponds to the generator output curve correction amount (ΔMW) determination 13 in FIG. 1.

The generator output target value is determined by adding the generator output correction amount (ΔMW) 13 thus determined to the generator output prediction curve. After that, the output of the generator that should be adjusted to this target value is controlled. This corresponds to the generator output control 14 with the new output curve in FIG. 1 as the target value.

In this way, it is possible to predict the generator output prediction curve based on the temperature of the day from the power output curve created based on the knowledge of the operator by using fuzzy inference, and increase or decrease the generator output in advance. Therefore, even if the general demand amount increases or decreases, there is no need to issue a sudden output fluctuation request command to each generator from the central power supply station, and stable power supply becomes possible.

[0035]

As described above, according to the present invention, the optimum generator output correction amount is obtained by fuzzy inference from the membership function of time, the membership function of temperature temperature deviation, and the generator output correction membership function. By calculating momentarily and controlling so as to follow that value, the generator output can be smoothly increased or decreased even with sudden changes in power demand due to changes in temperature, etc. to stabilize the system and provide stable power supply. It is possible to

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing a generator output curve for one day.

FIG. 3 is a diagram showing a membership function of time.

FIG. 4 is a diagram showing a membership function of temperature deviation.

FIG. 5 is a diagram showing a membership function of a generator output correction amount.

FIG. 6 is a diagram showing a procedure for determining a generator output correction amount from Table 1.

FIG. 7 is a diagram showing a synthesis function.

FIG. 8 is a graph showing a current day and an actual generator output curve.

[Explanation of symbols]

 10 ………… Knowledge base 11 ………… Temperature measurement 12 ………… Fuzzy reasoning unit 13 ………… Correction amount determination 14 ………… Control unit 21 ………… Generator output 22 ………… Time 23 ………… Generator Output α ………… Temperature deviation 100 ………… Generator output curve of the day (planned) 101 ………… Generator output curve of the day (actual)

Claims (1)

[Claims] 1. A control device for controlling a generator output, calculates a temperature deviation between an air temperature and an average temperature on the day, and corrects the generator output by fuzzy reasoning from a function of the time of the day and the temperature deviation. It is characterized in that the output of the generator is controlled so as to follow the target value by setting the generator output obtained by calculating the amount and adding this correction amount to the scheduled generator output curve. Electric power demand prediction control device.