JP2019060573A - Combustion system - Google Patents

Abstract

To early detect failure of a combustor.SOLUTION: A combustion controller 2 is provided with a failure determination unit 2-2. The failure determination unit 2-2 is configured to: monitor intensity of flame detected by a flame detector for each sequence (for example, "pilot trial", "pilot only", "main trial", "main stability") in a combustion sequence; and when the monitored intensity of flame is within a normal range determined for each sequence, but deviated from a regular state, determine that a combustor 22 is in a failure state.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a combustion system using a combustion control device that controls combustion in a combustion device.

  Conventionally, as a combustion system of this type, a combustion system provided with a system for supplying air to the combustion chamber and a system for supplying fuel to the combustion chamber, and a combustion control apparatus provided with a combustion control device for controlling the operation of the combustion apparatus (See, for example, Patent Document 1).

  In this combustion system, a supply system of air is disposed in a blower that blows air, an air flow path for guiding air blown from the blower to the combustion chamber, and passes through the air flow path. A damper (air flow adjustment damper) for adjusting the flow rate of air is provided.

  The fuel supply system is provided with a damper (fuel flow rate adjustment damper) for adjusting the flow rate of the fuel supplied to the combustion chamber through the fuel flow path, linked with the air flow rate adjustment damper to adjust its opening position. ing. The air flow control damper and the fuel flow control damper may not be linked.

  In the air flow path, there is disposed a wind pressure switch for detecting that the pressure of the air blown from the blower has reached a predetermined value, the wind pressure switch is turned on, and the damper (air flow rate adjustment damper The pre-purge time is measured starting from the time when the opening position of the fuel flow rate adjustment damper reaches a predetermined high opening position. When the pre-purge time is completed, the opening position of the damper (air flow adjustment damper / fuel flow adjustment damper) is set to a predetermined low opening position.

  Further, in this combustion system, the operation sequence from start of the combustion device to steady-state combustion is defined as a combustion sequence. For example, the operation order from the start of the combustion apparatus to steady-state combustion is "start check", "pre-purge", "wait for ignition", "pilot trial", "pilot only", "main trial", "main stable", Each combustion sequence is defined as "stationary combustion".

  Also, in this combustion system, the combustion control device monitors the state of the flame detector etc., and when an abnormality in the combustion device (such as misfire or extinguishment) is detected, closes the safety shut-off valve, and the fuel to the burner Shut off the supply of That is, the combustion device is brought into the lockout state.

JP, 2011-208921, A Japanese Utility Model Application Publication 63-173647

  However, in the conventional combustion system, even if malfunction (a state within the normal range but deviated from the normal state) occurs in the combustion device, there is no means for externally recognizing it. That is, although an abnormal phenomenon such as a decrease in the blower air volume or a slight air leak from the piping is not so great as to be abnormal but the combustion efficiency is poor, it can not be recognized from the outside.

  For this reason, the malfunction of the combustion device has progressed and appears as an abnormality such as a extinguishment or a misfire, which can only be recognized when the operation of the combustion device is stopped due to the abnormality, which hinders the stable operation of the entire combustion system . In addition, since there is no problem from the outside, it is necessary to regularly carry out maintenance for items that do not actually have a problem and need maintenance, resulting in an increase in cost.

  In Patent Document 1 described above, the abnormality generated in the combustion device is detected, and the combustion is stopped when the abnormality is detected. As described above, conventionally, the detection of the fact that the continuation of the combustion has reached an abnormality that can not be accepted is that the abnormality can be detected, but it took time to restore the combustion. Therefore, there has been a demand for development of a method capable of early detecting a malfunction of the combustion device.

  Further, Patent Document 2 discloses an abnormality detection device of a flame sensor configured to detect the presence or absence of an abnormality of the flame sensor from the light amount level input to the flame sensor (flame detector). However, the device shown in this patent document 2 aims to detect the presence or absence of abnormality of the flame detector, and intends to detect malfunction of the combustion device from the intensity of the flame detected by the flame detector. There is no.

  The present invention has been made to solve such problems, and an object of the present invention is to provide a combustion system capable of detecting a malfunction of a combustion device at an early stage.

  In order to achieve such an object, the present invention relates to a combustion device (22) provided with an air supply system (101) to a combustion chamber (5) and a fuel supply system (102), and an operation of the combustion apparatus. A flame configured to detect the flame intensity of burners (6, 7) of a combustion device in a combustion system (100) comprising a combustion control device (2) for controlling a fuel according to a predetermined combustion sequence The detector (9) and the flame intensity detected by the flame detector for each sequence in the combustion sequence are monitored, and the intensity of the flame is within the normal range defined for each sequence, but usually And a malfunction determining unit (2-2) configured to determine that the combustion apparatus is in a malfunctioning state.

  In the present invention, the malfunction judgment unit monitors the flame intensity detected by the flame detector for each sequence in the combustion sequence, and the monitored flame intensity is normally determined in each sequence. However, if it is out of the normal state, it is determined that the combustion device is in a malfunctioning state.

  For example, as a first example, the flame intensity detected by the flame detector is monitored at a fixed point for each sequence in the combustion sequence, and the flame intensity is within a normal range defined for each sequence. If it deviates from the normal state, it is determined that the combustion device is in a malfunctioning state.

  As a second example, the rate of change of the flame intensity detected by the flame detector is monitored for each sequence in the combustion sequence, and the rate of change of the monitored flame intensity is determined for each sequence. If it is within the range but deviates from the normal state, it is determined that the combustion device is in a malfunctioning state.

  As a third example, for each sequence in the combustion sequence, the statistics (average, variance, etc.) in one sequence of flame intensities detected by the flame detector are monitored, and the monitored flame intensities are If the statistical value is within the normal range defined for each sequence but deviates from the normal state, it is determined that the combustion apparatus is in a failure state.

  In the present invention, each sequence in the combustion sequence may be a partial sequence in the combustion sequence (e.g., "pilot trial", "pilot only", "main trial", "main stable"), or "combustion" It may be all sequences including the previous sequence and "steady combustion".

  In the above description, as an example, constituent elements on the drawing corresponding to constituent elements of the invention are indicated by reference numerals in parentheses.

  As described above, according to the present invention, the intensity of the flame detected by the flame detector is monitored for each sequence in the combustion sequence, and the intensity of the flame is determined for each sequence in a normal range. However, if the combustion device is out of the normal state, it is determined that the combustion device is in a failure state, so that the failure of the combustion device can be detected early.

FIG. 1 is a diagram illustrating an observation point of a frame voltage VF determined for each sequence. FIG. 2 is a diagram showing normal, normal, abnormal, and malfunctioning ranges for the frame voltage VF acquired at the observation point. FIG. 3 is a view showing the main part of the combustion system according to the embodiment of the present invention. FIG. 4 is a diagram illustrating the configuration of a combustion system in which only the main burner is used. FIG. 5 is a time chart of the combustion sequence from startup of the combustion device to steady-state combustion. FIG. 6 is a functional block diagram of the main part of the combustion control device. FIG. 7 is a flowchart showing processing in the malfunction determination unit in the “pilot trial”. FIG. 8 is a flowchart showing processing in the malfunction determination unit in “pilot only”. FIG. 9 is a flowchart showing processing in the malfunction determination unit in the “main trial”. FIG. 10 is a flowchart showing processing in the malfunction determination unit in “main stable”. FIG. 11 is a diagram showing an example in which the determination result in the malfunction determination unit in the combustion control device is sent to a monitoring device (remote monitoring device) of a remote place connected via the Internet. FIG. 12 is an image diagram of statistics in a sequence of one frame voltage VF.

  Hereinafter, embodiments of the present invention will be described in detail based on the drawings. First, an overview of the present embodiment will be described before the description of the embodiment.

[Outline of Embodiment]
In the present embodiment, the flame intensity detected by the flame detector is observed at a fixed point for each sequence in the combustion sequence. For example, as shown in FIG. 1, observation points are defined as X1, X2, X3, and X4 for each sequence (each combustion sequence) of "pilot trial", "pilot only", "main trial", and "main stable". The flame voltage VF according to the flame intensity detected by the flame detector is observed.

  Every time the combustion apparatus is operated, observation of the frame voltage VF at the fixed points X1, X2, X3 and X4 is repeated, and a data range which can be taken when there is no malfunction in each combustion sequence is derived as a normal range.

  Then, the fixed point observation is continued for each combustion sequence, and the flame voltage VF measured in each combustion sequence is within the normal range defined for each combustion sequence but deviates from the normal range. It is determined that there is a problem with

  For example, an average value of the frame voltage VF at the observation point X measured repeatedly is set as a reference frame voltage VFB (see FIG. 2), and a predetermined range centered on the reference frame voltage VFB is set as a normal range.

Then, during operation of the combustion device, monitors the frames voltage VF for each combustion sequence, although monitoring point frame voltage VF observed by X is in the (VFE _L <VF) range of normal, the normal range (VFL ≦ When it deviates from VF ≦ VFH), it is determined that the sequence is malfunctioning and the combustion apparatus is malfunctioning.

Incidentally, VFE _L is a threshold value for determining abnormality, VFE _L is set smaller than the lower limit value VFL normal range. Further, the reference frame voltage VFB may be determined not as an average value of the measured frame voltages VF but as an initial value at the start of operation.

  Further, the monitoring point of the frame voltage VF in each combustion sequence may not be one point, but may be a plurality of points. The use of multiple points can more surely detect a malfunction.

  Also, the frame voltage VF may not necessarily be monitored at a fixed point, and the frame voltage VF may be continuously observed to monitor the rate of change of the frame voltage VF, or the statistics within one sequence of the frame voltage VF. The values (average, variance, etc.) may be monitored.

  Alternatively, the frame current IF may be monitored instead of the frame voltage VF, and the malfunction may be determined in the same manner as the frame voltage VF. Further, the “pre-combustion” sequence or the “steady-state combustion” sequence may be added to the combustion sequence that monitors the frame voltage VF.

Embodiment
FIG. 3 shows the configuration of an embodiment of the combustion system according to the present invention. The combustion system 100 includes a combustion device 1, a combustion control device 2, a fuel flow path 3, and an air flow path 4.

  The combustion apparatus 1 includes a combustion chamber 5, a main burner 6 for heating the inside of the combustion chamber 5, a pilot burner 7 for igniting the main burner 6, and an ignition device (IG) 8 for igniting the pilot burner 7. A flame detector 9 for detecting the flame intensity of the burners (pilot burner 7 and main burner 6) and a temperature sensor 10 for detecting the temperature in the combustion chamber 5 are provided.

  The fuel flow path 3 is a flow path for supplying fuel to the combustion device 1 and includes a main flow path 3a to which fuel is supplied from the outside, and a first flow path 3b and a second flow branched from the main flow path 3a. It is comprised from the path 3c. The first flow path 3 b is connected to the main burner 6, and the second flow path 3 c is connected to the pilot burner 7. Further, a gas pressure switch 15 and a flowmeter (gas flowmeter) 20 are provided in the main flow passage 3a, and safety shutoff valves 11, 12 and a damper (fuel flow adjustment damper) 19 are provided in the first flow passage 3b. The safety shutoff valves 13 and 14 are provided in the second flow path 3c.

  One end of the air flow path 4 is connected to the blower 16, and the other end is connected to the first flow path 3b. Air (air) discharged from the blower 16 is supplied to the main burner 6 together with fuel (gas) via the first flow path 3b. In the air flow path 4, a wind pressure switch (air flow switch) 17, a flow meter (air flow meter) 21, and a damper (air flow adjustment damper) 18 are provided.

  In the air flow path 4, the air flow control damper 18 is driven by the control motor M in linkage with the fuel flow control damper 19. The control motor M has a high opening position sensor HS that detects that the opening position of the dampers 18 and 19 has reached a predetermined high opening position, and a low that detects that the opening position has reached a predetermined low opening position. An opening position sensor LS is provided.

  The combustion control device 2 includes a gas pressure signal from the gas pressure switch 15, an air pressure signal from the wind pressure switch 17, a flame detection signal from the flame detector 9 (a signal indicating the flame intensity of the burner), a temperature sensor 10 A temperature detection signal or the like is input, and control signals are output to the safety shutoff valves 11 to 14, the ignition device 8, the blower 16, the dampers 18, 19 and the like. As a result, the operation of the combustion device 22 shown by encircling the constituent elements in the figure by a dashed line is controlled.

  Depending on the type of combustion device 22, there is a type that extinguishes the flame of pilot burner 7 when ignition of main burner 6 is finished, and a type that continues the flame of pilot burner 7 even after ignition of main burner 6, etc. In the former type, 9 detects the flame intensity of the pilot burner 7 first, and then detects the flame intensity of the main burner 6. In the latter type, the flame strengths of the pilot burner 7 and the main burner 6 are detected together.

  In the present specification, both the pilot burner 7 and the main burner 6 are referred to as burners, and the flame detected by the flame detector 9 is referred to as the flame of the burner. FIG. 3 is of a type in which the flame of the pilot burner 7 continues even after ignition of the main burner 6, and the flame detector 9 detects the flames of the pilot burner 7 and the main burner 6 as flames of the burner.

  Further, in the combustion apparatus 22, the air flow path 4, the blower 16 and the air flow rate adjustment damper 18 constitute a supply system 101 of air to the combustion chamber 5, and the fuel flow path 3 (3a, 3b, 3c) The safety shutoff valves 11 to 14 and the fuel flow rate adjustment damper 19 constitute a fuel supply system 102 to the combustion chamber 5.

  There is also a type in which only the main burner is provided without providing a pilot burner, and in that type, as shown in FIG. 4, the inlet side and the outlet side of the main channel 3a are bypassed to A flow path 3c is provided, and a fuel flow rate adjustment damper 19 is provided between the burner 6 and a junction point on the outlet side of the main flow path 3a and the sub flow path 3c. In this case, the burner 6 doubles as a main burner and a pilot burner, and the pilot burner 7 becomes unnecessary.

  In the combustion system 100 (FIG. 3), the operation sequence from start of the combustion device 22 to steady-state combustion is defined as a combustion sequence. For example, the operation order from the start of combustion device 22 to steady combustion is "start check", "pre-purge", "wait for ignition", "pilot trial", "pilot only", "main trial", "main stable" Each combustion sequence is defined as “stationary combustion”.

  FIG. 5 shows a time chart of the combustion sequence from start of the combustion device 22 to steady state combustion. When the combustion control device 2 receives a start input (t1 point shown in FIG. 5 (a)), it sends a drive command to the control motor M in the opening direction (t1 point shown in FIG. 5 (d)) The air flow to the air flow path 4 is started (point t1 shown in FIG. 5 (b)). Thereby, the dampers 18 and 19 are opened, and the pressure in the air flow path 4 is increased.

  Then, when the pressure in the air flow passage 4 is increased (the pressure of air to the combustion chamber 5 is increased) and the pressure in the air flow passage 4 reaches a predetermined value, the wind pressure switch 17 is turned ON (FIG. 5 (c T2 point shown in). A period P1 from the point t1 to the point t2 is a time zone of "start check".

  When the wind pressure switch 17 is turned on and the high opening position sensor HS detects that the opening positions of the dampers 18 and 19 have reached the high opening position (t3 shown in FIG. 5 (e)). Point) The timing of the pre-purge time S1 is started from this time point.

  After the lapse of the pre-purge time S1, the combustion control device 2 sends a drive command in the closing direction to the control motor M (at t4 shown in FIG. 5D). Thus, the openings of the dampers 18 and 19 are closed. A period P2 from the point t3 to the point t4 is a time zone of "prepurge".

  When the low opening position sensor LS detects that the opening positions of the dampers 18 and 19 have reached the low opening position (t5 point shown in FIG. 5 (f)), the combustion control device 2 performs the predetermined waiting time S2 After that, the safety shutoff valves (pilot valves) 13 and 14 are opened (t6 point shown in FIG. 5 (g)), and the igniter (ignition) 8 is operated (t6 point shown in FIG. 5 (h)) The pilot burner 7 is ignited (t6 point shown in FIG. 5 (i)). A period P3 from the point t4 to the point t6 is a time zone of "waiting for ignition".

  When the combustion control device 2 ignites the pilot burner 7, the safety shut-off valves (main valves) 11 and 12 are opened after the lapse of time S3 which is the sum of the pilot ignition time and the pilot only time (see FIG. Ignition to the main burner 6 is performed at time t8 shown in 5 (j) (time t8 shown in FIG. 5 (k)). In this case, the period during which the igniter 8 is operated, that is, the period P4 from the point t6 to the point t7 shown in FIG. Is the "pilot only" time zone.

  When the combustion control device 2 ignites the main burner 6, the proportional control of the opening degree of the dampers 18 and 19 is started after the elapse of the time obtained by combining the main ignition time S4 and the main stabilization time S5 ( The transition to steady-state combustion is made at t10 point shown in FIG. 5 (d). Among the periods from t8 to t10, period P6 of main ignition time S4 is a time zone of "main trial", and period P7 of main stabilization time S5 is a time period of "main stability". Moreover, period P8 after t10 point is a time zone of "steady-state combustion (steady-state combustion sequence)".

  In the present embodiment, the combustion control device 2 that causes such operation according to the combustion sequence includes “a function to collect combustion control information”, “a function to determine a time zone of the combustion sequence”, and “a combustion device A function of determining a malfunction and a function of outputting a determination result are provided.

  In FIG. 6, the functional block diagram of the principal part of the combustion control apparatus 2 in this Embodiment is shown. The combustion control device 2 is realized by hardware including a processor and a storage device, and a program for realizing various functions in cooperation with the hardware, and the combustion control information as a function unit specific to the present embodiment A collection unit 2-1, a malfunction determination unit 2-2, and an output unit 2-3 are provided.

  In FIG. 6, only the functional units unique to the present embodiment provided in the combustion control device 2 are extracted and shown. Moreover, in FIG. 6, since the structure of the combustion apparatus 22 is shown by FIG. 3, it is abbreviate | omitting.

  In the combustion control device 2, the combustion control information collecting unit 2-1 collects combustion control information at a predetermined cycle (for example, in units of 0.1 s). In this embodiment, a start input signal (FIG. 5 (a)) indicating the operating state of the combustion device 22, a blower signal (FIG. 5 (b)) indicating the operating state of the blower 16, and supply of air to the main burner 6 A signal indicating the state (FIG. 5C), a high opening position detection signal indicating the arrival of the dampers 18 and 19 at the high opening position (FIG. 5E), and a low opening position of the dampers 18 and 19 Opening position detection signal (FIG. 5 (f)) indicating the arrival of the fuel, a signal (FIG. 5 (g)) indicating the fuel supply state to the pilot burner 7, and a signal indicating the operating state of the igniter (ignition) 8 (FIG. 5 (h)), a signal showing the supply state of fuel to the main burner 6 (FIG. 5 (j)), flame intensity of the burners (pilot burner 7 and main burner 6) detected by the flame detector 9. Detection signal, the flow rate of the fuel gas measured by the gas flow meter 20, Flowmeter 21 as a flow rate such as a combustion control information of the air to be measured, for example, collect 0.1s units.

  The combustion control device 2 acquires a flame detection signal from the flame detector 9 as a frame voltage VF, and determines the presence or absence of a flame, an ignition abnormality, and the like from the value of the frame voltage VF. The combustion control information collected by the combustion control information collection unit 2-1 includes information indicating the presence or absence of a flame determined by the combustion control device 2, information indicating a misfire, information indicating a extinguishment, a frame voltage VF, etc. .

  The malfunction determination unit 2-2 includes a combustion sequence determination unit 2-21 that determines which combustion sequence period the combustion device 22 is currently in. Based on the combustion control information collected by the combustion control information collection unit 2-1, the combustion sequence determination unit 2-21 has the combustion device 22 currently in a time zone (periods P1 to P8 shown in FIG. 5) of which combustion sequence. Determine the

  The output unit 2-3 outputs the determination result of the malfunction determination unit 2-2 to the monitoring device 23. The monitoring device 23 includes a display unit 23-1 that displays a monitoring screen on the display, and displays the determination result in the malfunction determination unit 2-2 from the combustion control device 2 on the monitoring screen displayed by the display unit 23-1. Do.

[A malfunction judgment unit]
In the malfunction judging unit 2-2, for the frame voltage VF of each combustion sequence, an upper threshold VFH and a lower threshold defining the normal range derived as described above with reference to FIG. and VFL, and normal or abnormal or not the threshold value VFE _L for determining the set.

In this embodiment, the upset decision unit _{2-2, VFH 1, VFL 1,} VFE L1 is set as a threshold value in the "Pilot Trial", VFH _2, VFL ₂ as a threshold value in the "pilot-only", VFE _L2 is set. _{Further, VFH 3, VFL 3, VFE} L3 is _{set, VFH 4, VFL 4, VFE} L4 is set as a threshold value in the "Main stable" as a threshold value in the "Main Trial".

[Pilot Trial]
When the period P4 for the "pilot trial" starts, the malfunction determination unit 2-2 burns the frame voltage VF (measured value) at the monitoring point X1 shown in FIG. 1 (YES in step S101 shown in FIG. 7). It acquires from the control information collection part 2-1 (step S102). Here, if the frame voltage VF is VFL ₁ ≦ VF ≦ VFH ₁ (YES in step S103), it is determined that the “pilot trial” is normal (step S105).

If the frame voltage VF is not VFL ₁ VF VF VF VFH ₁ (NO in step S103), the malfunction determination unit 2-2 determines whether the frame voltage VF is within the normal range (VFE _L1 <VF). It confirms (step S104).

  If the frame voltage VF is not within the normal range (NO at step S104), the malfunction determination unit 2-2 determines that the “pilot trial” is abnormal (step S106), and the frame voltage VF is within the normal range. If it is (YES in step S104), it is determined that the "pilot trial" is malfunctioning (step S107).

[Pilot only]
The malfunction determination unit 2-2 burns the frame voltage VF (measured value) at the monitoring point X2 shown in FIG. 1 (YES in step S201 shown in FIG. 8) when entering the period P5 of “pilot only” It acquires from the control information collection part 2-1 (step S202). Here, if the frame voltage VF is VFL ₂ ≦ VF ≦ VFH ₂ (YES in step S203), it is determined that “pilot only” is normal (step S205).

If the frame voltage VF is not VFL ₂ ≦ VF ≦ VFH ₂ (NO in step S203), the malfunction determination unit 2-2 determines whether the frame voltage VF is within the normal range (VFE _L2 <VF). It confirms (step S204).

  If the frame voltage VF is not within the normal range (NO at step S204), the malfunction determination unit 2-2 determines that “pilot only” is abnormal (step S206), and the frame voltage VF is within the normal range. If it is (YES in step S204), it is determined that "pilot only" is malfunctioning (step S207).

[Main trial]
When the period P6 for the "main trial" starts, the malfunction determination unit 2-2 burns the frame voltage VF (measured value) at the monitoring point X3 shown in FIG. 1 (YES in step S301 shown in FIG. 9). It acquires from the control information collection part 2-1 (step S302). Here, if the frame voltage VF is VFL ₃ ≦ VF ≦ VFH ₃ (YES in step S303), it is determined that the “main trial” is normal (step S305).

If the frame voltage VF is not VFL ₃ VF VF VF VFH ₃ (NO in step S303), the malfunction determination unit 2-2 determines whether the frame voltage VF is within the normal range (VFE _L3 <VF). It confirms (step S304).

  If the frame voltage VF is not within the normal range (NO at step S304), the malfunction determination unit 2-2 determines that the "main trial" is abnormal (step S306), and the frame voltage VF is within the normal range. If it is (YES in step S304), it is determined that the "main trial" is malfunctioning (step S307).

[Main stability]
When the period P7 for "main stable" is entered, the malfunction determination unit 2-2 burns the frame voltage VF (measured value) at the monitoring point X4 shown in FIG. 1 (YES in step S401 shown in FIG. 10). It acquires from the control information collection part 2-1 (step S402). Here, if the frame voltage VF is VFL ₄ ≦ VF ≦ VFH ₄ (YES in step S403), it is determined that “main stable” is normal (step S405).

If the frame voltage VF is not VFL ₄ ≦ VF ≦ VFH ₄ (NO in step S 403), the malfunction determination unit 2-2 determines whether the frame voltage VF is within the normal range (VFE _{L 4} <VF). It confirms (step S404).

  If the frame voltage VF is not within the normal range (NO at step S404), the malfunction determination unit 2-2 determines that "main stable" is abnormal (step S406), and the frame voltage VF is within the normal range. If there is any (YES in step S404), it is determined that "main stable" is malfunctioning (step S407).

  If the malfunction determination unit 2-2 determines that any of “pilot trial”, “pilot only”, “main trial”, and “main stability” is malfunctioning, it determines that the combustion device 22 is in a malfunctioning state, The determination result is sent to the monitoring device 23 through the output unit 2-3 and displayed on the monitoring screen of the monitoring device 23.

  In this case, on the monitoring screen of the monitoring device 23, it is determined that any one of "pilot trial", "pilot only", "main trial", and "main stable" is in a malfunction, that is, a malfunction. In order that the sequence name of the combustion sequence can be known, it is notified that the combustion device 22 is in a failure state. In this case, malfunction of the flame detector or the burner is suspected.

  When any one of “pilot trial”, “pilot only”, “main trial”, and “main stable” is determined to be abnormal in the malfunction determination unit 2-2, similarly to the case where it is determined to be malfunction, It is notified that the combustion device 22 is in an abnormal state.

  In this manner, in the present embodiment, it is possible to early know that the combustion device 22 is in a normal but malfunctioning state before reaching an abnormality. That is, it is possible to detect in advance the sign of abnormality of the combustion device 22 and to notify the administrator of the necessity of maintenance at an early stage before becoming an abnormal state. This eliminates the need for frequent maintenance and avoids cost increases.

  In addition, when the combustion device 22 is put in the lockout state, it takes time and effort to restore it, but since this can be prevented before the lockout state occurs, the burden on the administrator can be reduced. . In addition, it is possible to narrow down the cause of the malfunction by notifying the combustion sequence determined to be malfunction together.

  In the embodiment described above, the monitoring device 23 is provided separately from the combustion control device 2, and the determination result obtained by the malfunction determining unit 2-2 is displayed on the screen (monitoring screen) of the monitoring device 23. However, the combustion control device 2 may be provided with a display unit for displaying a monitoring screen, and the monitoring screen displayed by the display unit may display the determination result obtained by the malfunction determination unit 2-2.

  Further, as shown in FIG. 11, a transmission unit 2-4 is provided in the combustion control device 2, and a malfunction determination is made in the monitoring device (remote monitoring device) 23 at a remote place from the transmission unit 2-4 via the Internet 30. The determination result obtained by the unit 2-2 may be sent and displayed on the monitoring screen of the monitoring device 23.

  In the embodiment described above, the malfunction determination unit 2-2 is provided in the combustion control device 2. However, the malfunction determination unit 2-2 may not necessarily be provided in the combustion control device 2, and a diagnostic device separately from the combustion control device 2 The same function may be provided in this diagnostic device.

  Also, as described in the "Summary of the embodiment", the monitoring points of the frame voltage VF in each combustion sequence may be a plurality of points, and the frame voltage VF is continuously observed to monitor the rate of change of the frame voltage VF. Alternatively, statistics (average, variance, etc.) in a sequence of one frame voltage VF may be monitored. FIG. 12 shows an image of statistics in a sequence of one frame voltage VF. In the figure, the black circles are the average values in the one-time sequence, and the bars are the range of dispersion. Alternatively, the frame current IF may be monitored instead of the frame voltage VF, and the malfunction may be determined in the same manner as the frame voltage VF.

  Also, in this embodiment, the combustion sequence for monitoring the frame voltage VF is set to “Pilot Trial”, “Pilot Only”, “Main Trial”, “Main Stable”, but the sequence “Before combustion” (“Start check” “Pre-purge”, “waiting for ignition” or “steady-state combustion” may be added.

[Extension of the embodiment]
Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the above embodiments. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the technical idea of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Combustion apparatus, 2 ... Combustion control apparatus, 2-1 ... Combustion control information collection part, 2-2 ... Malfunction judgment part, 2-21 ... Combustion sequence judgment part, 2-3 ... Output part, 3 ... Fuel flow path 4, air passage 5, combustion chamber 6, main burner 7, pilot burner 8, ignition device 9, flame detector, 11-14 safety shut-off valve 15, gas pressure switch DESCRIPTION OF SYMBOLS 16 ... blower, 17 ... wind pressure switch (air flow switch), 18 ... air flow adjustment damper, 19 ... fuel flow adjustment damper, 20 ... gas flow meter, 21 ... air flow meter, 22 ... combustion device, 100 ... combustion System, 101: air supply system, 102: fuel supply system, HS: high opening position sensor, LS: low opening position sensor, M: control motor.

Claims (4)

A combustion system comprising: a combustion apparatus comprising an air supply system to a combustion chamber and a fuel supply system; and a combustion control apparatus controlling an operation of the combustion apparatus according to a predetermined combustion sequence.
A flame detector configured to detect the flame intensity of the burner of the combustion device;
The intensity of the flame detected by the flame detector is monitored for each sequence in the combustion sequence, and the intensity of the flame falls within the normal range defined for each sequence but deviates from the normal state And a malfunction determination unit configured to determine that the combustion device is in a malfunction state. In the combustion system according to claim 1,
The malfunction judging unit
The flame intensity detected by the flame detector is monitored at a fixed point for each sequence in the combustion sequence, and the monitored flame intensity is within the normal range defined for each sequence. It is determined that the combustion device is in a malfunctioning state if it deviates from a normal state. In the combustion system according to claim 1,
The malfunction judging unit
The rate of change of flame intensity detected by the flame detector is monitored for each sequence in the combustion sequence, and the rate of change of flame intensity monitored is a normal range defined for each sequence. A combustion system characterized by determining that the combustion device is in a malfunctioning state if it is out of the normal state but it is out of the normal state. In the combustion system according to claim 1,
The malfunction judging unit
The statistics in one sequence of flame intensities detected by the flame detector are monitored for each sequence in the combustion sequence, and the statistics of the monitored flame intensities are determined for each of the sequences. A combustion system characterized by determining that the combustion device is in a malfunctioning state if it is out of the normal state but within a normal range.

Images