JP3461480B2 - Control method of boiler device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a boiler device when a boiler is automatically operated. FIG. 3 is a block diagram showing the configuration of a typical conventional boiler apparatus 1. As shown in FIG. The boiler device 1 is, for example, a water tube boiler, and uses, for example, heavy oil as fuel. [0003] The supplied fuel is burned in a combustion chamber by a burner, and generated steam is discharged from a steam discharge pipe 4 connected to the steam drum 2. Further, combustion air is sent from the blower 8 to the combustion chamber. This combustion air supply amount is adjusted by the air supply amount adjustment device 9. Also,
Water is supplied to the drum 2 via a water supply valve 6. A control device 3 for controlling the boiler device 1 includes:
Combustion control is performed so that the drum vapor pressure is kept constant,
In addition, water supply control is performed so that the drum water level is kept constant. In the combustion control, a vapor pressure detector 5 for detecting the vapor pressure in the drum 2, a fuel supply amount detector 11 for detecting the supply amount of fuel, and an air supply amount detector 10 for detecting the supply amount of combustion air are provided. Based on this, the fuel supply valve 7 and the air supply amount adjusting device 9 are controlled so that the vapor pressure becomes a predetermined vapor pressure. In the water supply control, the water supply valve 6 is controlled so that the water level becomes a predetermined height based on the detection output of the water level detector 5 that detects the height of the water surface of the drum 2. [0005] In the water supply control, when the water level of the drum 2 exceeds a predetermined height, the water supply valve 6
And reduce water supply. Drum 2 when water supply decreases
However, since the burner load is constant at this time, the evaporation effect increases due to a decrease in the drum water amount, and a boiling state occurs. When boiling, the apparent water level rises temporarily due to boiling water. When this apparent rise in the water level is detected by the water level detector 5, the water supply control is performed to further reduce the water supply amount even though the actual water amount is decreasing. This causes the water level to be lower than the predetermined height. [0006] When the burner load is constant and the amount of water decreases in this manner, the vapor pressure increases. When the vapor pressure increases, the fuel supply is reduced by combustion control, and the burner load is reduced. As a result, the boiling state subsides, the detected value of the drum water level is greatly reduced, and the water supply valve is greatly opened by the water supply control to greatly increase the water supply amount. As a result, the drum water level becomes higher than the predetermined height again. In this way, the drum water level hunts, and the water supply control becomes unstable. [0007] The temperature of the supplied water is 50-60 ° C.
Therefore, when the water supply amount increases in a state where the burner load is reduced, the water in the drum is rapidly cooled, and the steam pressure is rapidly reduced. This again increases the burner load. In this way, the hunting of the drum water level makes the combustion control unstable, and the control of the entire boiler device becomes unstable. As described above, the conventional control method has a problem that it is difficult to stably control the boiler. When two boilers connected to each other with steam discharge pipes are operated at the same time, the two boilers are controlled to have the same steam pressure. In such a state, as described above, when the water level rises in one of the boilers and the control becomes unstable, and the steam pressure fluctuates, this steam pressure fluctuation is transmitted to the other boiler via the steam discharge pipe. When the steam pressure of the other boiler device fluctuates, this causes the control of the entire boiler device to become unstable in the other boiler device as described above. In this way, when two boilers are operated at the same time, they interfere with each other, and it becomes more difficult to control more stably than when one boiler is used. [0010] If the water supply control is carried out as in the case of a main boiler of a turbine ship to solve such a problem, the control becomes stable. However, in this case, a large number of detectors and the like are required, and the cost increases. I will. Further, for example, Japanese Patent Laid-Open No.
Japanese Patent Publication No. 106310 discloses a water supply control device for a boiler that follows a rapid change in steam consumption. However, it is difficult to solve the above-mentioned problem by the method described in this publication. An object of the present invention is to provide a method for controlling a boiler apparatus which can stably control a boiler without increasing the cost. The present invention comprises two boiler units 21 and 22 having the same configuration, and comprises two boiler units 21 and 22.
Are connected to each other, and in each of the boiler devices 21 and 22, the first PI control circuit 4 is controlled based on the detection output Ld of the water level detection means 32 for detecting the water level of the boiler.
9, the first water supply valve opening command value Cw1 is calculated and the water supply valve 33 is controlled so that the water level of the boiler becomes the predetermined height Ls, and the steam pressure detection means 31 detects the steam pressure Pd of the boiler. Based on the detection output, the first PID control circuit 41
In the control method of the boiler device which controls the fuel supply valve 35 by the first fuel supply amount command values C1a and C1b so that the vapor pressure becomes a predetermined pressure, each of the boiler devices 2
In steps 1 and 22, the fuel supply pressure Fd of the fuel supplied by the fuel supply valve 35 is detected by the fuel supply pressure detecting means 34, and the detected fuel supply pressure Fd corresponds to the detected fuel supply pressure Fd. To the fuel supply amount Fq
A water supply amount setting means for storing a predetermined maximum water supply amount according to the fuel supply amount and deriving a second water supply valve opening command value Cw2 which is a maximum water supply amount according to the detected fuel supply pressure Fd;
0, the lower selector 51 selects the smaller one of the first and second water supply valve opening command values Cw1 and Cw2, and controls the water supply valve 33, Hunting of the drum water level is prevented, and each of the boiler devices 21 and
By two high-order selectors 42, two boiler units 21,
22, the higher first fuel supply amount command value is selected from among the first fuel supply amount command values C1a and C1b, and the second PID control circuit 43 selects the converted fuel supply amount Fq.
Is calculated by calculating the second fuel supply amount command value C2 so as to be the higher first fuel supply amount command value.
The air supply amount adjusting means for controlling the air supply amount of each of the boilers 21 and 22 outputs an air supply amount detection value Ad by the air supply amount detector 37, and outputs the detected fuel amount. Based on a first air supply amount setting value As1 corresponding to the supply pressure Fd and the higher first fuel supply amount command value, a signal of the first air supply amount setting value As1 and the higher first fuel The signal of the supply amount command value is added by an adder 47, and the output of the adder 47 is multiplied by a proportional constant α determined in advance by a multiplier 46 to obtain a second air supply amount setting value A.
The second PI control circuit 48 calculates the air supply amount detection value A detected by the air amount detector 37.
A method for controlling a boiler device, comprising calculating an air supply amount command value Ca such that d becomes a second air supply amount set value As2, and adjusting the air supply amount in response to the air supply amount command value Ca. is there. According to the present invention, the maximum water supply amount according to the fuel supply amount is stored in advance in the water supply amount setting means, and the water supply amount is limited from increasing beyond the maximum water supply amount. Therefore, when it is attempted to greatly increase the water supply amount by water supply control in a state where the burner load is reduced, the water supply amount is limited to be larger than the maximum water supply amount based on the fuel supply amount. It is surely prevented that the water in the drum is rapidly cooled by the increase in the temperature. This prevents the drum water level from hunting and making the water supply control unstable. This also prevents the steam pressure from becoming unstable and the combustion control from becoming unstable, thereby stabilizing the control of the entire boiler device. Further, in the present invention, it is not necessary to newly add a detector and the like, and only the water supply valve is controlled using the existing detector, and only the software needs to be changed. It is possible to stably control the boiler device without causing it to run. According to the present invention, since the current fuel supply amount is a detection output of the fuel supply amount detecting means, a decrease in the water supply amount is determined based on, for example, a fuel supply amount command value to the fuel supply valve. The water supply amount can be controlled in accordance with the actual burner load, and the control can be satisfactorily performed, as compared with the case of limiting. According to the present invention, in the combustion control, the supply amount of combustion air is controlled based on the change in the fuel supply amount, but the air supply amount is controlled in response to the detection output of the fuel supply amount detecting means. Control may not be able to follow actual burner load fluctuations. In view of this point, in the present invention, the air supply amount is controlled based on a fuel supply amount command value which is a command value to the fuel supply valve. That is, the air supply amount is controlled based on the fuel supply amount command value that precedes the actual fuel supply amount change, and combustion air can be supplied quickly in response to the burner load change. As described above, two boiler devices are provided,
When the steam discharge pipes are connected to each other, if both boilers are operated at the same time, fluctuations in the steam pressure of one boiler are transmitted to the other boiler, and the two boilers interfere with each other to make the control more unstable. However, in the present invention, even when such two boiler devices are provided,
Since each can be controlled stably, it is possible to reliably prevent the two boilers from interfering with each other and making the control more unstable. FIG. 1 is a schematic diagram showing a configuration of a boiler apparatus 20 using a method for controlling a boiler apparatus according to an embodiment of the present invention. The boiler device 20 is, for example, a water tube boiler, and includes two boiler devices, a first boiler device 21 and a second boiler device 22. Such a boiler device 20 is used, for example, for driving a turbine for cargo handling with a tanker or the like, or for generating steam used in a ship. Each of the boilers 21 and 22 has an evaporation amount of 44 tons / hour per can and uses heavy oil as fuel. Connected to the air / water drum 30 of the first boiler device 21;
A first steam discharge pipe 26 for discharging steam, and a second steam discharge pipe 27 connected to the steam drum 30 of the second boiler device 22
Are connected to each other and share a steam outlet.
During the automatic operation, the first boiler device 21
Water supply control and combustion control are performed by the second boiler device 22, and water supply control and combustion control are performed by the second control device 24. These control devices 23 and 24 are
It is composed of a C (Programmable logic controller). Since the first boiler device 21 and the second boiler device 22 have the same configuration, only the first boiler device 21 will be described below, and the second boiler device 22 will attach the same reference numeral to the corresponding configuration, Description is omitted. Heavy oil as fuel is supplied to the combustion chamber of the first boiler device 21 together with air, and is atomized from a burner (not shown) and blown into the combustion chamber for combustion. The pressure of the supplied fuel is detected by a fuel supply pressure detector 34, and the fuel supply amount is detected as a pressure. The combustion air is sent into the combustion chamber by a blower 36. The adjustment of the supply amount of the combustion air is performed by the air supply amount adjusting device 38. The air supply adjusting device 38 includes an inlet guide vane, and adjusts the air supply by adjusting the angle of the vane. The supplied air amount is detected by an air supply amount detector 37. The air supply amount detector 37 calculates the supplied air flow rate based on the pressure difference between the wind box and the combustion chamber. Water heated to about 50-60 ° C. is supplied to the drum 30, and the amount of water supplied is controlled by a water supply valve 33. The water level of the drum 30 is detected by a water level detector 32. The vapor pressure in the drum 30 is detected by a vapor pressure detector 31. The control device 23 performs water supply control so that the drum water level is maintained at a predetermined height, and performs combustion control so that the drum vapor pressure is maintained at a predetermined pressure. FIG. 2 is a block diagram showing the configuration of the control device 23. In the following description, the first boiler device 21
And the case where the second boiler device 22 is operated simultaneously. The fuel supply valve 35 is controlled based on the vapor pressure detector 31 and the fuel supply pressure detector 34. The vapor pressure Pd in the drum 30 detected by the vapor pressure detector 31 is equal to the first P
It is input to an ID (proportional-integral-derivative) control circuit 41. First
The pressure set value Ps is input to the PID control circuit 41 from the steam pressure setting circuit 40, and feedback control is performed so that the steam pressure Pd becomes the pressure set value Ps. The vapor pressure setting circuit 40 stores a predetermined vapor pressure according to the elapsed time from the start of operation, and stores a pressure set value Ps according to the elapsed time in the first PID control circuit 41.
To enter. At the start of operation, since the water is not warm, the pressure set value Ps is set low, and after a lapse of a predetermined time, the pressure set value Ps is given so as to become a predetermined pressure. The boiler device 21 is operated in two modes, a high pressure mode and a low pressure mode, and one of the modes is selected by a high / low pressure switch 52. The vapor pressure setting circuit 40 is based on the set mode,
After a lapse of a predetermined time, the pressure set value Ps corresponding to the high pressure or low pressure mode is input to the first PID control circuit 41. Based on the detected steam pressure Pd and the pressure set value Ps from the steam pressure setting circuit 40, the first PID control circuit 41 provides a first fuel supply amount command value C1a such that the steam pressure Pd becomes the pressure set value Ps. Is calculated and input to the high-order selector 42. The first fuel supply amount command value C1a is
High-order selector 4 of second control device 24 of second boiler device 22
2 is input. The second control device 24 also calculates the first fuel command value C1b based on the steam pressure detector 31 and the steam pressure setting circuit 40 of the second boiler device 22, and calculates the first fuel supply amount command value C1b as the first fuel supply amount command value C1b. It is input to the high-order selector 42 of the boiler device 21. The first steam discharge pipe 26 of the first boiler device 21
And the second steam discharge pipe 27 of the second boiler device 22 are connected to each other, so that when the first boiler device 21 and the second boiler device 22 are operated at the same time, or when one of the steam pressures is high, Only emits its higher vapor pressure,
Since the lower steam pressure is not discharged, it is necessary to control the first and second boiler devices 21 and 22 so that the steam pressures are equal. Therefore, for example, when the steam pressure of the first boiler device 21 is lower than the steam pressure of the second boiler device 22, the steam pressure of the first boiler device 20 is increased in accordance with the steam pressure of the second boiler device 22. Need to be controlled. In the present embodiment, the first fuel supply amount command value C1a calculated by the first PID control circuit 41 of the first boiler device 21 and the first fuel supply amount command value C1b calculated by the second boiler device 22 are higher. Since the higher command value is input to the selector 42 and the higher command value is selected here, the first and second boiler devices 21 and 22 are both controlled based on the selected higher command value. . Thereby, the steam pressures of the two boiler devices 21 and 22 can be made equal.
Here, it is assumed that the first fuel command value C1a calculated by the first boiler device 21 has been selected. The first fuel command value C1a selected by the high-order selector 42 is input to the second PID control circuit 43. Further, the fuel supply pressure Fd detected by the fuel supply pressure detector 34
Is converted by the fuel supply amount conversion circuit 45 into a fuel supply amount Fq which is a fuel flow rate, and is input to the second PID control circuit 43. The second PID control circuit 43 calculates a second fuel supply amount command value C2 such that the fuel supply amount Fq becomes the first fuel supply amount command value C1a. The valve opening of the fuel supply valve 35 is adjusted based on the second fuel supply amount command value C2, and feedback control is performed so that the vapor pressure Pd of the drum 30 becomes the pressure set value Ps. Next, a control method of the air supply amount adjusting device 38 will be described. The air supply amount detection value Ad detected by the air supply amount detector 37 is input to a PI (proportional-integral) control circuit 48. The fuel supply pressure detection value Fd detected by the fuel supply pressure detector 34 is input to the air supply amount setting circuit 44. In the air supply amount setting circuit 44, an air supply amount corresponding to the fuel supply pressure, that is, an air supply amount necessary for the fuel supply amount is stored in advance, and the air supply amount corresponding to the input fuel supply pressure detection value Fd is stored. One air supply amount set value As1 is derived. The signal of the first air supply amount set value As1 is added by the adder 47 to the signal of the first fuel supply amount command value C1a output from the high-order selector 42, and the adder 47
Is multiplied by a proportional constant α in a multiplier 46 to calculate a second air supply amount set value As2. This second air supply amount set value As2 is input to the PI control circuit 48. The PI control circuit 48 calculates an air supply amount command value Ca such that the air supply amount detection value Ad becomes the second air supply amount set value As2. Air supply adjusting device 38
Adjusts the air supply amount in response to the air supply amount command value Ca. In this way, the feedback control is performed so that the air supply amount becomes the second air supply amount set value As2. Although the air supply amount is adjusted in accordance with the burner load, that is, the fuel supply amount, merely adjusting the air supply amount in response to the value detected by the fuel supply pressure detector 34 causes the actual burner load to be reduced. The air supply may not be able to follow the fluctuation. In view of this point, in the present embodiment, not only the air supply amount set value is derived based on the fuel supply pressure detection value, but also the first fuel supply amount command value C1a which is a command value to the fuel supply valve 35. Calculated based on Fuel supply amount command value C
Since 1a is a command signal to the fuel supply valve 35, it fluctuates prior to the fluctuation of the fuel supply pressure. Therefore, by calculating the air supply amount setting value based on the signal value that fluctuates in advance, it is possible to adjust the air supply amount quickly following the change in the burner load. Next, the water supply control will be described. The drum water level detection value Ld detected by the water level detector 32 is input to the PI control circuit 49. The PI control circuit 49 includes:
A predetermined set water level Ls is input, and the PI control circuit 49
Calculates the first valve opening command value Cw1 such that the drum water level detection value Ld becomes the set water level Ls. The water supply valve 33 is controlled based on the first valve opening command value Cw1, and is feedback-controlled so that the drum water level becomes the set water level Ls. If the amount of supplied water is greatly increased while the burner load is reduced, the water in the drum 30 is rapidly cooled and the control becomes unstable. Therefore, the maximum water supply amount for rapidly cooling the water in the drum 30 and preventing the control from becoming unstable is
Stability control can be performed by determining in advance according to the burner load and performing control so that the water supply amount does not increase more than the maximum water supply amount according to the current burner load. In the present embodiment, the fuel supply pressure is used as a value corresponding to the burner load, and the fuel supply pressure and the valve opening of the water supply valve corresponding to the maximum water supply amount corresponding to the fuel supply pressure are used as the water supply amount setting circuit. 50 in advance, and a water supply amount setting circuit 5
In the case of 0, the maximum valve opening is derived as the second water supply valve opening command value Cw2 based on the fuel supply pressure Fd from the fuel supply pressure detector 34, and is input to the low-order selector 51 via the changeover switch 55. The first water supply valve opening command value Cw1 from the PI control circuit 49 and the second water supply valve opening command value Cw2 from the water supply amount setting circuit 50 are input to the low-order selector 51. The degree command value is selected. The second water supply valve opening command value Cw2 is the maximum water supply amount for preventing the control from becoming unstable, and increases in accordance with the fuel supply amount. Therefore, when the burner load is high and the fuel supply amount is large, Usually, the first water supply valve opening command value Cw1 is smaller, and the water supply valve is controlled based on the first water supply valve opening command value Cw1. However, as described above, the water in the drum boils, and the drum water level rises temporarily,
When the steam pressure is high and the burner load is reduced, the boiling state subsides and the drum water level decreases, and accordingly, the first water supply valve opening command value Cw1 increases and the second water supply valve If the opening command value Cw2 is exceeded, the second water supply valve opening command value Cw2 is selected by the low-order selector 51, and the second water supply valve opening command value Cw2 is selected.
The water supply valve is controlled by the water supply valve opening command value Cw2.
As a result, the amount of water supplied to the drum
Rapid cooling of the water inside is prevented. As a result, hunting of the drum water level is prevented, and the control of the entire first boiler device 21 is stabilized. The changeover switch 55 can be switched between a water supply amount setting circuit 50 side and a 100% valve opening degree setting side. Usually, the changeover switch 55 is located on the water supply amount setting circuit 50 side and calculated by the water supply amount setting circuit 50. The obtained second valve opening command value Cw2 is input to the low-order selector 51. The lower limit water level DLs is set in advance in the changeover switch 55. If the drum water level is lower than the lower water level DLs by more than the set water level Ls of the drum, the water supply setting circuit 50 breaks down and becomes unnecessary. It is determined that the amount of water supply is limited, and the changeover switch 55 switches to the 100% valve opening command value side. Thereby, the low-order selector 51
, The 100% valve opening command value is input to the low-order selector 51 as the second valve opening command value Cw2. Therefore, the low-order selector 51 selects the first valve opening command value Cw1, and the water supply valve 33 is controlled by the first valve opening command value Cw1. In this way, it is possible to reliably detect the failure of the water supply amount setting circuit 50 and prevent the water supply amount from being excessively limited. In this embodiment, the lower limit water level D
Ls is set to 50 mm. When the first boiler device 21 and the second boiler device 22 are operated at the same time, a change in the steam pressure of the first boiler device is conventionally transmitted to the second boiler device, and the two boiler devices interfere with each other. However, in the present invention, the first and second boiler devices 21 and
2 can be stably controlled by controlling as described above, so that it is possible to reliably prevent the control from becoming unstable due to interference with each other. Further, in the control method of the present invention, the water supply control is performed using the fuel supply pressure detection value conventionally used for the combustion control, so that it is not necessary to newly provide a detector or the like.
It is only necessary to change the software, and stable boiler control can be realized at low cost. In this embodiment, the second water supply valve opening command value Cw
2 is a fuel supply pressure detection value Fd from the fuel supply pressure detector 34
However, the control method of the present invention is not limited to such a form. For example, the second water supply amount command value Cw2 may be calculated based on the first fuel supply amount command value C1a or the second fuel supply amount command value C2. It may be derived. Further, the control method of the present invention relates to the boiler device 2
The present invention can be applied not only to the case where both the first and the second are driven at the same time, but also to the case where one of the two is driven. Although the above embodiment has been described as a water tube boiler, the control method of the present invention is not limited to such a form, and can be applied to general control of a boiler. As described above, according to the present invention, when the burner load is reduced and the fuel supply amount is reduced, when the water supply amount is to be rapidly increased, the water supply amount is changed according to the fuel supply amount. By limiting the increase in the water supply than the predetermined maximum water supply, hunting of the drum water level can be prevented, and the control of the entire boiler can be stabilized. Further, according to the present invention, by controlling the air supply amount based on the fuel supply amount command value, it is possible to adjust the air supply amount quickly following the change in the burner load. That is, according to the present invention, two boiler devices 2
Thus, the air supply amount can be adjusted by quickly following the change in the burner load in the first and second burners, and therefore, the two boiler devices 21 and 22 can be operated stably. Even when two boilers are provided, the two boilers can be stably controlled by applying the control method of the present invention.
It is possible to prevent the two boiler devices from interfering with each other and becoming unstable.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing a configuration of a boiler device 20 using a control method for a boiler device according to an embodiment of the present invention. FIG. 2 is a block diagram showing a configuration of a control device 23. FIG. 3 is a schematic diagram showing a configuration of a conventional boiler device 1. DESCRIPTION OF SYMBOLS 20 Boiler device 21 First boiler device 22 Second boiler device 23 First controller 24 Second controller 26 First steam discharge pipe 27 Second steam discharge pipe 30 Drum 31 Steam pressure detector 32 Water level detection Device 33 water supply valve 34 fuel supply pressure detector 35 fuel supply valve 36 blower 37 air supply amount detector 38 air supply amount adjustment device

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-56-100203 (JP, A) JP-A-59-42405 (JP, U) Toshiro Terano and Moto Takeuchi, “Automatic Boiler Control,” First Edition , Ohm Co., Ltd. April 30, 1971 P6, 7, 224, 225, 241-243, 316-320 (58) Fields investigated (Int. Cl. ⁷ , DB name) F22D 5/00 F22D 5 / 26 F22B 35/00

Claims (1)

(57) [Claims 1] Two boiler units 2 having the same configuration
The steam output pipes 26 and 27 of the two boiler devices 21 and 22 are connected to each other.
d, the first PI control circuit 49 calculates the first water supply valve opening command value Cw1 so that the water level of the boiler becomes the predetermined height Ls, controls the water supply valve 33, and sets the steam pressure Pd of the boiler. The first PID control circuit 41 controls the fuel supply valve 35 by the first fuel supply amount command values C1a and C1b based on the detection output of the vapor pressure detection means 31 for detecting the fuel pressure so that the vapor pressure becomes a predetermined pressure. In the control method of the boiler device, each of the boiler devices 21 and 22 has a fuel supply pressure F of the fuel supplied by the fuel supply valve 35.
d is detected by the fuel supply pressure detecting means 34, and the detected fuel supply pressure Fd is converted into a fuel supply amount Fq corresponding to the detected fuel supply pressure Fd, and a predetermined maximum value corresponding to the fuel supply amount is determined. Water supply amount setting means 5 for storing the water supply amount and deriving a second water supply valve opening command value Cw2 which is the maximum water supply amount according to the detected fuel supply pressure Fd.
0, the lower selector 51 selects the smaller one of the first and second water supply valve opening command values Cw1 and Cw2 to control the water supply valve 33, Hunting of the drum water level is prevented, and the high-order selector 42 of each of the boiler devices 21 and 22 prevents
Fuel supply amount command values C1 of the two boiler devices 21 and 22
a, the higher first fuel supply amount command value is selected from C1b, and the second PID control circuit 43 makes the converted fuel supply amount Fq the higher first fuel supply amount command value. As described above, the second fuel supply amount command value C2 is calculated, the fuel supply valve 35 is controlled, and the air supply amount adjusting means for adjusting the supply amount of the combustion air of each of the boiler devices 21 and 22 is provided. The air supply amount detection value Ad is output by the device 37, and based on the first air supply amount set value As1 corresponding to the detected fuel supply pressure Fd and the higher first fuel supply amount command value, The signal of the first air supply amount set value As1 and the signal of the higher first fuel supply amount command value are added by an adder 47. The output of the adder 47 is proportional to a predetermined ratio by a multiplier 46. Multiply by the constant α to obtain the second air supply amount set value As2 is calculated, and the air amount detector 37 is calculated by the second PI control circuit 48.
Calculating the air supply amount command value Ca at which the air supply amount detection value Ad detected by the above becomes the second air supply amount set value As2, and adjusting the air supply amount in response to the air supply amount command value Ca. A method for controlling a boiler device.