JP4134442B2 - Combustion device control method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for controlling a combustion apparatus.
[0002]
[Prior art]
The control method of the air volume adjusting means and the fuel supply means in the conventional combustion apparatus is controlled in cooperation with each other based on the signal output according to the operating condition of the load facility. That is, when the operating condition of the load facility becomes high and the heat demand increases, the air volume adjusting means and the fuel supply means are controlled to increase the air volume and the fuel supply volume and switch the combustion state of the burner. When heat demand is reduced, the air volume and fuel supply are reduced. When switching the combustion state of the burner, if the capacity of the burner is small, it is easy to change the air volume and the amount of fuel supplied in the same way, but if the capacity of the burner increases, It is difficult to change the supply amount in the same manner. When controlling to increase the combustion amount, the air flow adjustment causes a time lag, so that the air flow may be smaller than the fuel supply amount, the combustion becomes unstable, and extinguishing, incomplete combustion and dust generation occur. Further, when controlling to reduce the combustion amount, the air volume may be larger than the fuel supply amount, and similarly, the combustion becomes unstable, and there is a problem in that extinction or incomplete combustion occurs.
[0003]
When controlling to increase the combustion amount, in order to prevent the combustion from becoming unstable, control to delay the increase in the fuel supply amount by the time until the air flow increases, and control to decrease the combustion amount When performing the control, the control was performed to delay the decrease in the fuel supply amount by the time until the air volume decreases. When the control for delaying the fuel supply amount is performed, an angle sensor for detecting the rotation angle of the air volume adjusting means or a delay timer is used. When the delay timer is used, for example, when the control for increasing the combustion amount is performed, the control for delaying the increase of the fuel supply amount by the fixed transition timing time until the air amount increases is performed.
[0004]
Next, a control method for switching the combustion state of the conventional burner will be described with reference to FIG. In FIG. 5, for the sake of explanation, control when switching from the low combustion state to the high combustion state is shown. That is, the abscissa indicates the passage of time, the upper part of the ordinate indicates the air volume, and shifts to an L amount when low combustion is performed and to an H amount when high combustion is performed. Since the air volume adjustment causes a time delay, the amount of L gradually shifts to the amount of H. Further, there is an individual difference for each product. For example, the product A may be an operation of the upper line with the air flow shown in FIG. 5, and the product B may be an operation of the lower line with the air flow shown in FIG. Further, as shown in the lower part of FIG. 5, when the control for increasing the combustion amount is performed, the increase in the fuel supply amount is delayed by the fixed transition timing time D until the air amount increases. At this time, there is an individual difference for each product, and as shown in FIG. 5, the air volume at the time of switching at the fixed transition timing time D is the air volume E for the product A and the air volume F for the product B. Since there is a difference between the two, adjustment work is required for each product.
[0005]
[Problems to be solved by the invention]
However, in the conventional combustion apparatus control method, the structure of the angle sensor is complicated and expensive. The fuel supply amount transition delay time when the delay timer is used is the control of the fixed transition timing time, and there is an individual difference in the air amount transition delay time of the air amount adjusting means for each product, so incomplete combustion occurs. In order to prevent this, it is necessary to individually adjust the air volume adjusting means.
[0006]
This invention is made in view of the said subject, and the invention of Claim 1 is a combustion provided with the air volume adjustment means provided in the ventilation path | route from a fan to a burner, and the fuel supply means to the said burner When the combustion state of the burner is switched, the apparatus control method detects a time required for switching the air volume adjusting means, calculates a degree of adjustment of the air volume adjusting means based on the detected value, and calculates the calculated value. The supply amount of the fuel supply means is controlled based on the above, and the time required for switching the air volume adjusting means is detected based on the current value of the drive unit of the air volume adjusting means .
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a case where the embodiment of the present invention is applied to a boiler combustion apparatus will be described. This embodiment is a method for controlling a combustion apparatus including a flow path from a blower to a burner, for example, an air volume adjusting means, such as a damper, provided in a blow duct, and a fuel supply means, for example, an electromagnetic valve, to the burner. When the combustion state of the burner is switched, the time required for switching the air volume adjusting means is detected, the degree of adjustment of the air volume adjusting means is calculated based on the detected value, and the fuel supply is calculated based on the calculated value The supply amount of the means is controlled.
[0009]
The time required for switching the air volume adjusting means is detected based on the current value of the drive unit of the air volume adjusting means.
[0010]
【Example】
Specific embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic explanatory view showing an embodiment in which the present invention is applied to a boiler combustion apparatus (reference numeral omitted). FIG. 2 is an explanatory diagram of the operation of the damper. In FIG. 1, the combustion device is a so-called burner 2 portion and is attached to the upper part of a boiler 5. The combustion apparatus includes a fuel supply pipe 6, a wind box 7 and a blowing path for combustion air including a blow duct 3 connected to the wind box 7, and a blower 1 connected through the blowing path. Yes. The blower duct 3 includes a damper 4 (air volume adjusting means) that controls the air volume at two positions, a high combustion air volume position Y (see FIG. 2) and a low combustion air volume position X (see FIG. 2).
[0011]
The damper 4, that is, the air volume adjusting means is of a type that adjusts the combustion amount in stages, and in the illustrated embodiment, corresponds to a three-position control system, and the combustion amount is stopped, low combustion, Adjusted to three stages of high combustion. Specifically, the fuel supply pipe 6 includes two branch pipes, a low combustion valve 9 is connected to the low combustion fuel supply pipe 8, and the high combustion fuel supply pipe 10 is connected to the fuel supply pipe 10. Has a configuration in which a high-fuel valve 11 is connected. Then, by selectively opening and closing the low fuel valve 9 and the high fuel valve 11, the supply amount of the low fuel valve 9 and the high fuel valve 11, that is, the fuel supply means can be adjusted stepwise. The low fuel valve 9, the high fuel valve 11, the damper 4, and the blower 1 are connected to the controller 13 via wiring 12. The controller 13 includes a combustion control program for realizing the combustion control method according to the embodiment of the present invention. This combustion control program includes a program for controlling the low fuel valve 9, the high fuel valve 11, the damper 4 and the blower 1. Furthermore, a chimney 14 for discharging exhaust gas from the combustion device is provided at one end of the boiler 5.
[0012]
Next, the operation of the damper 4 will be described with reference to FIG. The damper 4 is disposed on the shaft 15 in the air duct 3. The damper 4 is constrained to the position of the low fuel locking tool 17 by the rotation of the torque motor 16 that is a drive part of the damper 4 during low combustion. The damper 4 operates so as to reduce the cross-sectional area of the blower duct 3 in the blower duct 3 and restricts the amount of air sent from the blower 1 so that the air volume corresponds to low combustion. At the time of high combustion, the torque motor 16 is constrained to the position of the high fuel locking tool 18 by reverse rotation. The damper 4 operates so as to increase the cross-sectional area of the blower duct 3 in the blower duct 3, and increases the amount of air sent from the blower 1 to obtain an airflow corresponding to high combustion. That is, the damper 4 moves in the range of the rotation angle C.
[0013]
Next, a control method for switching so as to increase the combustion amount of the burner 2 will be described with reference to FIGS. FIG. 3 is a current characteristic diagram of the torque motor 16 that is a drive unit of the damper 4. The torque motor 16 is configured to hold the damper 4 at a predetermined angle while the rotation of the torque motor 16 is restrained by the low-flame locking tool 17. That is, when the torque motor 16 is restrained by the low-flame locking device 17, a restraining current constantly flows. When switching the combustion state, if a reverse signal is output from the controller 13, the current of the torque motor 16 is once lost, increases when starting reverse rotation, and is restrained again by the high-fuel stop 18. It becomes a binding current. The time until the restraint current value I of the torque motor 16 becomes the restraint current value I when the reverse signal is output from the controller 13, that is, the time J required for switching the damper 4 is controlled. Store in the vessel 13. The restraint current value I is detected by a current detection circuit (not shown) arranged in the controller 13.
[0014]
FIG. 4 is an explanatory diagram showing the operation of the present invention. There is an individual difference for each product. For example, the product A has the air flow shown in FIG. 4 and the operation of the upper line, and the product B has the air flow shown in FIG. 4 and the operation of the lower line. In the case of the product A, the time K required for switching the damper 4 stored in the controller 13 is detected, the adjustment degree of the damper 4 is calculated based on the detected value, and the transition is performed based on the calculated value. The controller 13 outputs a signal for opening the high fuel valve 11 delayed by the timing time M. In the product B, the time N required for switching the damper 4 stored in the controller 13 is detected, the adjustment degree of the damper 4 is calculated based on the detected value, and the transition timing time is calculated based on the calculated value. The controller 13 outputs a signal for opening the high fuel valve 11 with a delay of P. By calculating the time required for switching the damper 4 for each product, when the damper 4 is switched, there is no individual difference in the air volume for each product, and the same switching set air volume Q is obtained. The angle of the damper 4 at this time is the transition angle R in FIG.
[0015]
Similarly, in the control method for switching the burner 2 to reduce the combustion amount in this embodiment, the time required for switching the damper 4 stored in the controller 13 is detected, and based on the detected value. The degree of adjustment of the damper 4 is calculated, and a signal for closing the high fuel valve 11 is output from the controller 13 with a delay of the transition timing time based on the calculated value. The angle of the damper 4 at this time is the transition angle S in FIG.
[0016]
【The invention's effect】
According to the present invention, when switching the combustion state of the burner, there is no complicated angle sensor, and there is no fixed transition timing time control using a delay timer. Individual differences in delay time can be eliminated, and work for individually adjusting the air volume adjusting means is eliminated. Further, it is easy to change the air volume and the supply amount of fuel in the same manner, the combustion becomes unstable, and the occurrence of extinguishing, incomplete combustion and dust is reduced.
[Brief description of the drawings]
FIG. 1 is a schematic explanatory view showing an embodiment in which the present invention is applied to a combustion apparatus for a boiler.
FIG. 2 is a diagram illustrating the operation of a damper.
FIG. 3 is a current characteristic diagram of a torque motor which is a drive unit of a damper.
FIG. 4 is an explanatory diagram showing the operation of the present invention.
FIG. 5 is an operation explanatory view of a damper of a control method for switching the combustion state of a conventional burner.
[Explanation of symbols]
1 Blower 2 Burner 4 Damper 5 Boiler 9 Low Fuel Valve 11 High Fuel Valve 13 Controller 16 Torque Motor 17 Low Fuel Locking Tool 18 High Fuel Locking Tool

Claims (1)

A method for controlling a combustion apparatus comprising an air volume adjusting means provided in a blowing path from a blower 1 to a burner 2 and a fuel supply means to the burner 2, wherein when the combustion state of the burner 2 is switched, the air volume Detecting the time required for switching the adjusting means, calculating the degree of adjustment of the air volume adjusting means based on the detected value, and controlling the supply amount of the fuel supplying means based on the calculated value;
The method of controlling a combustion apparatus , wherein the time required for switching the air volume adjusting means is detected based on a current value of a drive unit of the air volume adjusting means .

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