JPS61285314A - Controlling device for used number of burners - Google Patents

Abstract

PURPOSE:To prevent concentrated usage on specific burners by selecting order in such a manner that in an automatic controlling device of a boiler as heading, the number of times for ignition and extinction operations is memorized and the burners having the least number of operation times are selected primarily. CONSTITUTION:A counter 1 adds up the number of ignition and extinction of burners for each burner A-D on the basis of action signals from limit switches for open and closed valves of burners. Among burners A-D, burners having the least number of usage are selected by a comparator 2 for number of usage and logic 1 to that burners is transmitted and to other burners logic 0 is transmitted. When the number of usage is same, the order depends on predetermined order. On the other hand, a commanding transmitter 4 for increasing and reducing the number of burners outputs commands for increasing and reducing in response to required conditions. By this, a logic circuit 3 outputs action commands to burners having the least number of operations selected by the comparator for the number of usage. By this constitution, concentrated usage on specific burners is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an on/off burner selection device applied to an automatic boiler burner control device.

A conventional burner automatic control device for a boiler has a function of automatically increasing or decreasing the number of burners used depending on the load or the like. For example, if the burner oil pressure or boiler load increases, the number of burners used is increased, and vice versa.

At this time, conventionally, which burners are to be turned on or extinguished in a predetermined order, for example, from the lower burner to the upper burner of the boiler.

Problems to be Solved by the Invention In recent years, as the weight of nuclear power generation has increased in boilers, especially power generation boilers, the frequency of daytime load fluctuations, late night shutdowns, and early morning starts has increased significantly. The automatic burner control device now turns the burner on and off when the fire occurs. Traditionally, which burner to turn on and off was determined by
Since the burner is fixed in a fixed order determined by the burner arrangement, especially during the day when partial load fluctuations occur repeatedly,
Only a specific burner is concentrated and repeatedly turned on and off, and as a result, mechanically movable parts such as burner valves, burner insertion/extraction air cylinders, etc. that make up the burner automatic control device may be damaged due to wear and fatigue. It's getting expensive.

The present invention aims to eliminate the above-mentioned drawback, that is, the intensive use of a particular burner.

Means for Solving the Problems According to the present invention, a counter that stores the number of times each burner is turned on and off, a number comparator that selects the burner that has the least number of times that it is turned on and off, and a logic circuit that issues a turn off command. When the burner oil pressure or boiler load changes and the number of burners needs to be increased or decreased, priority is given to the burner that has been lit and extinguished the least number of times.

The action point extinguishing frequency counter is a signal indicating burner ignition and extinguishing.
For example, each time a signal for opening/closing a burner valve or inserting/removing a burner gun is received, the number is increased by one. Select the burner with the smallest counter value of each burner,
When a command to increase or decrease the number of burners is received, the selected burner is ignited or extinguished. As a result, it is possible to prevent a particular burner from repeatedly turning on and off in a concentrated manner, accelerating wear and fatigue of the mechanical parts, and thus extending the life of the burner as a whole.

Embodiment FIG. 1 shows an example of a burner number control device according to the present invention, and FIG. 2 shows field-installed equipment related to the burner automatic control device.

In FIG. 2, a flow control valve 11 controls the flow rate of fuel supplied to the boiler 10. In FIG. The shutoff valve 12 shuts off fuel supplied to the boiler 10 in an emergency.

The burner oil pressure transmitter 13 measures the pressure of fuel oil supplied to burners A, B, C, and D. A burner valve 14 is provided for each burner and is opened and closed for turning on and off the burner, and the apparatus according to the invention shown in FIG. 1 is associated therewith. Although not shown, there is also an atomization valve that opens and closes in conjunction with burner extinguishing, and an air cylinder that inserts and pulls out the burner gun.

In FIG. 1, reference numeral 1 indicates a burner extinguishing number counter, 2 a number comparator, 3 a logic circuit, and 4 a burner number increase/decrease command transmitter.

Signal representing burner point extinguishing, e.g. burner valve opening/closing I
The signal from the J-mitswitch is fed back to the burner extinguishing frequency counter 1 for each burner A, B, C, and D and is manually inputted, and the burner extinguishing frequency counter 1 is incremented by 1 each time a signal is received.

If the value of counter 1 reaches the upper limit of digits,...
The smallest counter value is subtracted from the counter values of all burners, and the value in counter 1 is always kept below the upper limit, thereby preventing overflow.

Among all the burner counter values, the burner showing the minimum value is selected by the number comparator 2, and a logic 1 is transmitted to the output corresponding to that burner. Outputs corresponding to other burners will be logic 0.

Since the values of the counters may be the same, the priority order should be determined in advance in preparation for this case. For example, the order can be from burners A to B, C, and D.

The burner number increase/decrease command transmitter 4 operates according to the burner oil pressure or the boiler load, and transmits a command to increase or decrease the number of burners using logic 1, for example. When a logic 1 command is issued, the AND gate of the logic circuit 3 passes the signal from the number comparator 2. As a result, the burner with the least number of times of ignition and extinguishing is selected as the burner to be actually ignited or extinguished. The logic 1 signal output through this logic circuit 3 is transmitted to the corresponding burner valve 14 in FIG.

Effects of the Invention According to the present invention, the number of times the burners are turned on and extinguished is stored in the counter 1, and the burner with the least number of times turned off is selected by the number comparator 2. Therefore, when a command to increase or decrease the number of burners is received, The burner with the least number of times of extinguishing will actually be extinguished, so the burners will always be kept at approximately the same number of times of extinguishing, and the entire boiler will be In addition to prolonging the life of the burner, it also prevents specific burners from rapidly wearing out, becoming fatigued, or otherwise failing.

4. Brief description of aspects FIG. 1 is a diagram showing a burner number control device according to the present invention, and FIG. 2 is a diagram showing equipment related to the burner automatic control device to which the device of the present invention is applied.

1. Burner point extinguishing number counter, 2. Number comparator,
3. Logic circuit, 4. Number of burners (and 1 other person)

Claims (1)

[Claims] In a burner number control device that controls the number of ignited burners by issuing a command to ignite and extinguish the burners according to the load, there is a counter that stores the number of times each burner is ignited and extinguished, and a counter that stores the number of times each burner is ignited and extinguished. This burner number control device is equipped with a number comparator for selecting the least number of burners, and a logic circuit that sends a command to turn off the burner to the burner that has the least number of turn-offs when a command to increase or decrease the number of burners is issued.