KR19980085384A - Combustion Control Method of Gas Boiler - Google Patents

Abstract

The present invention relates to a combustion control method of a gas boiler, and more specifically, to determine the combustion state in the burner by using wind pressure data, fan driving voltage data, and salt voltage data of the exhaust flue stored during initial ignition. The present invention relates to a combustion control method of a gas boiler that can optimally control the combustion state in a burner by changing the rotation speed of a fan.

The combustion control method of the gas boiler according to the present invention includes a gas valve (3) for adjusting the gas output amount in accordance with a control signal from a microcomputer (33) in which a program for controlling the entire stroke is incorporated, and a burner (8) generated during combustion. An infrared sensor 5 for outputting an electrical signal according to the state of the flame to be input to the microcomputer 33 and a wind pressure sensor 27 installed on one side of the exhaust flue 22 to detect wind pressure as a signal proportional to the magnitude. In the gas boiler including the fan drive unit 23 and the circulation pump 17 for supplying the air required for combustion and for driving the fan 21 used to discharge the gas burned by the burner 8. A first step of inputting and storing the ignition reference wind pressure (P) at the time of initial ignition, the fan driving voltage (V) at ignition, and the ignition salt voltage (F) at the ignition when the combustion stroke is started; A second step of comparing the magnitudes of the ignition reference wind pressure P and the fan wind pressure P1 in the microcomputer 33 when the ignition is completed and the normal combustion state is confirmed; If the fan wind pressure (P1) is greater than the ignition reference wind pressure (P), the third step of fixing the fan driving voltage (V1) by reducing the reference value to be higher than the ignition salt voltage (F) until the reference value is greater than the ignition salt voltage (F) ; If the fan wind pressure (P1) is less than the ignition reference wind pressure (P), the microcomputer 33 recognizes the reverse wind and increases until the reference value is lower than the ignition salt voltage (F1) to fix the fan driving voltage (V1), A fourth step of driving at the ignition reference fan driving voltage V when the fan wind pressure P1 and the ignition reference wind pressure P are the same; When the salt voltage (F1) is greater than the reference value compared to the salt voltage (F1) during combustion while the fan drive voltage (V1) is fixed, the fan voltage (V1) becomes less than the reference value. The fifth step of lowering the voltage until the fan drive voltage V1 is fixed and increasing the fan drive voltage V1 to operate at the normal fan drive voltage when the salt voltage F1 during combustion is lower than the reference value. Characterized in that consisting of.

Description

Combustion Control Method of Gas Boiler

The present invention relates to a combustion control method of a gas boiler, and more specifically, to determine the combustion state in the burner by using wind pressure data, fan driving voltage data, and salt voltage data of the exhaust flue stored during initial ignition. The present invention relates to a combustion control method of a gas boiler that can optimally control the combustion state in a burner by changing the rotation speed of a fan.

Gas boilers are increasingly used due to the reduction of pollution factors and ease of handling by using clean fuel gas. These gas boilers use LPG or LNG, and use the high temperature heat generated by burning fuel in the burner to convert low temperature direct water into high temperature heating water and then circulate through the pipe installed in the room to perform heating. have. In addition, the hot water is heated to a high temperature and then supplied to the kitchen or toilet to use hot water.

1 is a configuration example of a gas boiler conventionally used, and briefly describes an operation state. When the boiler is operated by the user, the fan 21 is operated for a predetermined time to perform a pre-purge stroke to completely discharge the harmful gas remaining in the combustion chamber 6 and the exhaust flue. After the pre-purge stroke is completed, the fuel gas LPG or LNG is supplied to the burner 8 after being adjusted to a predetermined pressure while passing through the gas valve 3 through the pipe. In response to a control signal from a microcomputer (not shown) in the state where fuel is supplied, the high voltage generated from the ignition transformer 7 discharges from the ignition plug and ignites the gas to start combustion.

Confirmation of the ignition state is detected using the infrared sensor 5 installed on the outer wall of the combustion chamber (6). That is, the infrared sensor 5 detects a change in the wavelength of the flame in the burner 8, that is, the sulfur salt or the blue salt, and outputs an electric signal corresponding to the blue flame when the flame is completely burned. It is determined that the ignition is completed by receiving.

The heat of combustion generated by combustion in the burner 8 heats the heating water filled therein while passing through the heat exchanger 9 provided in the upper portion of the combustion chamber 6. When the heating water is raised to a predetermined temperature set by the user, the heating is performed while circulating the room through the pipe connected by the rotational force of the circulation pump 17.

Although not described in detail in the drawing, a plurality of temperature measuring sensors for measuring the heating water temperature are provided on the pipe surface adjacent to the heat exchanger 9. When using hot water, the flow switch 19 detects the movement state of water flowing through the inside of the pipe connected to the microcomputer to exchange the flow path appropriately to tap the hot water. The combusted exhaust gas is discharged to the outside through an exhaust hood installed on the combustion chamber 6 and an exhaust flue 22 connected to the exhaust port 11.

However, in the conventional gas boiler having the above-described configuration, there is a problem in that extinguishing or incomplete combustion occurs during combustion in the burner. In other words, when the back wind or pure air flows from the outside during combustion in the burner, the boiler is extinguished by the back wind sensing device, or the combustion becomes unstable due to the peroxygen supply in the case of the pure wind. The reverse wind is to prevent the discharge of the exhaust gas by the wind flows from the outside through the exhaust flue 22, the pure wind refers to the wind that is excessive oxygen is introduced into the combustion chamber from the inside of the gas boiler to be peroxide combustion.

The present invention has been made to solve the above problems, and an object of the present invention is to prevent the gas boiler from extinguishing or incomplete combustion due to external factors such as reverse wind or pure air generated during combustion of the gas boiler. It is to provide a combustion control method of a gas boiler that can provide an optimal combustion state.

The combustion control method of the gas boiler of the present invention for achieving the above object includes a gas valve 3 for adjusting a gas output amount in accordance with a control signal from a microcomputer 33 in which a program for controlling the entire stroke is incorporated, and a burner ( 8) the infrared sensor 5 which outputs an electrical signal according to the state of the flame generated during combustion and inputs it to the microcomputer 33, and is installed on one side of the exhaust flue 22 to detect the wind pressure as a signal proportional to the magnitude A wind pressure sensor 27 for supplying air for combustion, and a fan driver 23 for driving a fan 21 used to discharge the gas burned by the burner 8, and a circulation pump 17. In the gas boiler including, when the combustion stroke starts, the ignition reference wind pressure (P) at the initial ignition, the fan drive voltage (V) at the ignition, and the flame voltage (F) at the ignition are input and stored in the microcomputer 33. The first step to do; A second step of comparing the magnitudes of the ignition reference wind pressure P and the fan wind pressure P1 in the microcomputer 33 when the ignition is completed and the normal combustion state is confirmed; If the fan wind pressure (P1) is greater than the ignition reference wind pressure (P), the third step of fixing the fan driving voltage (V1) by reducing the reference value to be higher than the ignition salt voltage (F) until the reference value is greater than the ignition salt voltage (F) ; If the fan wind pressure (P1) is less than the ignition reference wind pressure (P), the microcomputer 33 recognizes the reverse wind and increases until the reference value is lower than the ignition salt voltage (F1) to fix the fan driving voltage (V1), A fourth step of driving at the ignition reference fan driving voltage V when the fan wind pressure P1 and the ignition reference wind pressure P are the same; When the salt voltage (F1) is greater than the reference value compared to the salt voltage (F1) during combustion while the fan drive voltage (V1) is fixed, the fan voltage (V1) becomes less than the reference value. The fifth step of lowering the voltage until the fan drive voltage V1 is fixed and increasing the fan drive voltage V1 to operate at the normal fan drive voltage when the salt voltage F1 during combustion is lower than the reference value. Characterized in that consisting of.

1 is a schematic diagram of a gas boiler conventionally used;

2 is a partial block circuit diagram of the gas boiler of FIG.

3 is a flowchart for explaining the method of the present invention.

Explanation of symbols for the main parts of the drawings

1: gas boiler, 3: gas valve,

5: infrared sensor, 6: combustion chamber,

7: ignition transformer, 8: burner,

9: heat exchanger, 11: exhaust,

13: tank, 15: hot water heat exchanger,

17: circulation pump, 19: flow switch,

21: fan, 22: exhaust year,

23: fan drive unit, 25: rotation speed detection unit,

27: wind pressure sensor, 29: display unit,

31: input unit, 33: microcomputer.

Hereinafter, a combustion control method of the gas boiler of the present invention will be described in detail with reference to the accompanying drawings.

The method of the present invention is a method of controlling the combustion state in a burner using three factors, the wind pressure of the exhaust flue, the fan drive speed, and the salt voltage. In other words, by changing the fan driving voltage (fan rotation speed) according to the counter-wind or forward wind, which is an external disturbance factor that greatly affects the combustion in the burner installed inside the combustion chamber, the amount of air supplied to the combustion chamber is actively controlled to provide an optimum combustion state. That's how.

As described above, the method of the present invention includes the following steps: When the combustion stroke starts, the ignition reference wind pressure (P) during initial ignition, the fan driving voltage (V) during ignition, and the ignition salt voltage (F) data during ignition ( A first step of inputting and storing in 33); A second step of comparing the magnitudes of the ignition reference wind pressure P and the fan wind pressure P1 in the microcomputer 33 when the ignition is completed and the normal combustion state is confirmed; If the fan wind pressure (P1) is greater than the ignition reference wind pressure (P), the third step of fixing the fan driving voltage (V1) by reducing the reference value to be higher than the ignition salt voltage (F) until the reference value is greater than the ignition salt voltage (F) ; If the fan wind pressure (P1) is less than the ignition reference wind pressure (P), the microcomputer 33 recognizes the reverse wind and increases until the reference value is lower than the ignition salt voltage (F1) to fix the fan driving voltage (V1), A fourth step of driving at the ignition reference fan driving voltage V when the fan wind pressure P1 and the ignition reference wind pressure P are the same; When the salt voltage (F1) is greater than the reference value compared to the salt voltage (F1) during combustion while the fan drive voltage (V1) is fixed, the fan voltage (V1) becomes less than the reference value. The fifth step of lowering the voltage until the fan drive voltage V1 is fixed and increasing the fan drive voltage V1 to operate at the normal fan drive voltage when the salt voltage F1 during combustion is lower than the reference value. It consists of.

2 is a partial block circuit diagram of a gas boiler in which the method of the present invention is performed. The gas valve 3 adjusts the amount of gas supplied to the burner according to the control signal from the microcomputer 33, and the infrared sensor 5 measures the salt voltage to detect the combustion state in the burner.

The ignition transformer 7 also generates a high voltage according to the control signal of the microcomputer 33 and supplies it to the ignition plug. The circulation pump 17 is operated to forcibly move the heating water, and the fan 21 is rotated in accordance with the voltage applied from the fan driver 23. The rotation speed of the fan 21 is measured by the rotation speed detection unit 25 and input to the microcomputer 33, and stored in the internal memory device of the microcomputer 33.

The wind pressure sensor 27 is installed in the exhaust flue and outputs an electric signal corresponding to the strength of the wind pressure passing through the microcom 33. The display unit 29 is a part for displaying the operating state of the boiler, and the input unit 31 is a part for the user to input temperature data, time setting data, etc. for controlling the operation of the boiler.

Referring to the operating state of the gas boiler according to the method of the present invention is as follows.

When the ignition stroke is completed after the boiler is operated by the user and the normal combustion state is confirmed, the microcomputer 33 measures the reference wind pressure data P, the fan drive voltage data V, and the salt voltage data F measured at ignition. To the internal memory device. The combustion state is confirmed by comparing the electric signal input from the infrared sensor 5 with the microcomputer 33. If the combustion state is sulfur salt, it is recognized as incomplete combustion and blue flame as complete combustion. Of course, the determination of the ignition state is performed by the microcomputer 33 using the voltage (or current) value input from the infrared sensor 5.

In this state, the microcomputer 33 measures the fan wind pressure P1 in the current state input from the wind pressure sensor 27. The measured fan wind pressure P1 is compared with the ignition reference wind pressure P by the microcomputer 33. The purpose of this comparison is to regard the wind pressure at the ignition reference wind pressure (P) as a normal state, and to determine that the fan wind pressure (P) is higher than this and that the forward wind is generated, and if the wind pressure is less, the reverse wind is generated.

As a result of the comparison, when the fan wind pressure P1 is determined to be a pure wind larger than the ignition reference wind pressure P, this means that excessive air is introduced, thereby reducing the fan speed in order to reduce the air volume. This can be achieved by lowering the fan drive voltage V1, which is confirmed by measuring the salt voltage.

That is, the number of revolutions of the fan 21 decreases according to the voltage drop and the amount of air decreases accordingly. The voltage drop continues until the ignition salt voltage F is equal to or less than the reference value, and the fan driving voltage V1 is specified. It is fixed to the value.

In addition, as a result of the comparison, if the fan wind pressure P1 is determined to be less than the ignition reference wind pressure P, this means that the amount of air is insufficient, so that the fan speed is increased in the microcomputer 33 to increase the air volume. This can be achieved by raising the fan drive voltage V1, and the voltage rise is also detected by measuring the salt voltage F1.

That is, as the voltage increases, the rotation speed of the fan 21 increases and accordingly the amount of air increases, and the voltage rise continues until the ignition salt voltage F is equal to or greater than the reference value, and the fan driving voltage V1 is a specific value. Is fixed to.

This process is to detect reverse wind or pure wind and selectively deal with each of them. In other words, when it is detected as reverse wind, it is a standard for raising the driving fan voltage value V1 to increase the amount of air. In order to reduce the amount of air, it is to select a criterion for lowering the driving fan voltage value V1.

As described above, when the fan driving voltage with respect to the salt voltage is determined for the forward wind or the reverse wind, the microcomputer 33 fixes the voltage value for each. In the fixed state, the microcomputer 33 continuously measures the salt voltage using the infrared sensor 5 and compares it with the reference value. The salt voltage reference value indicates the voltage value of the salt voltage in the normal combustion state, and is a value in the clean state. When the fan driving voltage value is fixed as described above, the change of the salt voltage is monitored based on the salt voltage reference value.

If the salt voltage is higher than the reference value due to the influence from the outside (whether it is reverse wind or pure wind) during combustion, the microcomputer 33 will lower the salt voltage than the reference value (i.e. to prevent excessive supply of air for combustion). ) It lowers fan driving voltage. This falling state continues until the fan drive voltage equal to the reference value.

If the salt voltage measured by the infrared sensor 5 is less than the reference value, the microcomputer 33 immediately increases the fan driving voltage to increase the salt voltage above the reference value (that is, to sufficiently supply air for combustion). . This rising state continues until the fan drive voltage equal to the reference value is reached. If the salt voltage and the reference value is the same value, the microcomputer 33 performs the combustion stroke by keeping the fan driving voltage constant.

During the combustion stroke according to the method of the present invention by changing the fan driving voltage V1 to adjust the air volume as described above, when the operation stop signal of the boiler is input, the microcomputer 33 stops combustion in the burner and the fan A post-purge stroke is performed to continuously operate the 21 and the circulation pump 17. This is essentially the same as by conventional control methods.

As described above, according to the present invention, there is an advantage in that the gas boiler is prevented from extinguishing or incomplete combustion due to external factors such as reverse wind or pure wind generated during combustion of the gas boiler, and an optimum combustion state can be provided. .

Although the invention has been described in detail only with respect to the described embodiments, it will be apparent to those skilled in the art that modifications and variations can be made within the spirit and scope of the invention, and such variations or modifications will belong to the appended claims. .

Claims (1)

The gas valve 3 for adjusting the gas output amount according to the control signal from the microcomputer 33 having a program for controlling the entire stroke, and the burner 8 to output an electrical signal according to the state of the flame generated during combustion. An infrared sensor 5 input to the microcomputer 33, a wind pressure sensor 27 installed at one side of the exhaust flue 22 to detect wind pressure as a signal proportional to the magnitude, and supply air for combustion In a gas boiler comprising a fan driver 23 for driving a fan 21 used to discharge gas burned by the burner 8 and a circulation pump 17, A first step of inputting and storing the ignition reference wind pressure (P) at the time of initial ignition, the fan drive voltage (V) at ignition, and the ignition salt voltage (F) at the ignition when the combustion stroke is started; A second step of comparing the magnitudes of the ignition reference wind pressure P and the fan wind pressure P1 in the microcomputer 33 when the ignition is completed and the normal combustion state is confirmed; If the fan wind pressure (P1) is greater than the ignition reference wind pressure (P), the third step of fixing the fan driving voltage (V1) by reducing the reference value to be higher than the ignition salt voltage (F) until the reference value is greater than the ignition salt voltage (F) ; If the fan wind pressure (P1) is less than the ignition reference wind pressure (P), the microcomputer 33 recognizes the reverse wind and increases until the reference value is lower than the ignition salt voltage (F1) to fix the fan driving voltage (V1), A fourth step of driving at the ignition reference fan driving voltage V when the fan wind pressure P1 and the ignition reference wind pressure P are the same; And When the salt voltage (F1) is greater than the reference value compared to the salt voltage (F1) during combustion while the fan drive voltage (V1) is fixed, the fan voltage (V1) becomes less than the reference value. The fifth step of lowering the voltage until the fan drive voltage V1 is fixed and increasing the fan drive voltage V1 to operate at the normal fan drive voltage when the salt voltage F1 during combustion is lower than the reference value. Combustion control method of a gas boiler, characterized in that consisting of.