JP2019060570A - 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, when any one of an ignition delay time Td in an ignition sequence, consumption current Ic of an igniter, frame voltage VF, a flow rate FA of air to a combustion chamber, and a flow rate FF of fuel gas to the combustion chamber is within a predetermined normal range, 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 sequence from the start of the combustion apparatus to steady-state combustion is "start check", "pre-purge", "wait for ignition", "pilot ignition (ignition sequence)", "pilot only", "main ignition", " Each combustion sequence is defined as "main stable" and "steady 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

  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.

  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. In the combustion system (100) provided with the combustion control device (2) for controlling according to a predetermined combustion sequence, the information of the predetermined monitoring item during the control of the operation of the combustion device by the combustion control device is used as the combustion control information Based on the combustion control information collection unit (2-1) configured to collect and the combustion control information in a predetermined sequence in the combustion sequence, the malfunction is out of the normal state but within the normal range. And a malfunction determination unit (2-2) configured to determine whether or not the vehicle is in the normal state.

  In the present invention, for example, as the combustion control information in the predetermined sequence, the combustion control information collecting unit determines that the flame is present from the flame intensity detected by the flame detector from the start of ignition to the burner in the ignition sequence. At least one of the following: ignition delay time until discharge current consumed by the ignition device, flame intensity detected by the flame detector, air flow rate to the combustion chamber, and fuel gas flow rate to the combustion chamber Do. In this case, the malfunction determination unit determines the ignition delay time in the ignition sequence collected by the combustion control information collection unit, the consumed current of the ignition device, the flame intensity detected by the flame detector, the flow rate of air to the combustion chamber, If any of the flow rates of the fuel gas to the combustion chamber falls within a predetermined normal range but deviates from the normal state, it is determined that the combustion apparatus is in a failure state. In the present invention, the flame strength detected by the flame detector may be a flame voltage or flame current according to the flame strength.

  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, based on the combustion control information in the predetermined sequence in the combustion sequence, whether or not the combustion device is in the normal range but in a malfunction state deviated from the normal state. As a result, the malfunction of the combustion apparatus can be detected at an early stage.

FIG. 1 is a view showing a normal, normal, abnormal, and malfunctioning range with respect to the ignition delay time Td. FIG. 2 is a diagram showing normal, normal, abnormal, and malfunctioning ranges with respect to the frame voltage VFθ at the opening degree θ. 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 in the first embodiment. FIG. 7 is a flowchart showing processing in the malfunction determination unit during the ignition sequence. FIG. 8 is a time chart during an ignition sequence at normal time. FIG. 9 is a diagram corresponding to FIG. 8 when the fuel flow rate is reduced. FIG. 10 is a diagram corresponding to FIG. 8 when the air flow rate is excessive. FIG. 11 is a flowchart showing processing in the malfunction determination unit with respect to the ignition delay time Td in the ignition sequence. FIG. 12 is a flowchart showing processing in the malfunction determination unit with respect to the consumption current Ic of the ignition device in the ignition sequence. FIG. 13 is a flowchart showing processing in the malfunction determination unit with respect to the frame voltage VF in the ignition sequence. FIG. 14 is a flowchart showing processing in the malfunction determination unit with respect to the air flow rate FA in the ignition sequence. FIG. 15 is a flowchart showing processing in the malfunction determination unit with respect to the fuel flow rate FF in the ignition sequence. FIG. 16 is a functional block diagram of a main part of the combustion control device in the second embodiment. FIG. 17 is a flowchart showing processing in the malfunction determination unit during the steady-state combustion sequence. FIG. 18 is a flowchart showing processing in the malfunction determination unit with respect to the frame voltage VF in the steady combustion sequence. FIG. 19 is a flowchart showing processing in the malfunction determination unit with respect to the air flow rate FA in the steady combustion sequence. FIG. 20 is a flowchart showing processing in the malfunction determination unit with respect to the fuel flow rate FF in the steady-state combustion sequence. FIG. 21 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.

  Hereinafter, embodiments of the present invention will be described in detail based on the drawings. First, before starting the description of the embodiment, an outline of the present embodiment (first embodiment, second embodiment) will be described.

[Outline of Embodiment 1]
In the first embodiment, the ignition delay time Td from the start of ignition to the burner to the flame intensity detected by the flame detector during the ignition sequence until the flame is determined to be present, the consumption current Ic of the ignition device, and the flame detection The flame voltage VF, the flow rate of air to the combustion chamber (air flow rate) FA, and the flow rate of fuel gas to the combustion chamber (fuel flow rate) FF are measured according to the flame intensity detected by the unit.

  The measurement of the ignition delay time Td during this ignition sequence, the consumption current Ic of the ignition device, the frame voltage VF, the air flow rate FA, and the fuel flow rate FF is repeated each time the combustion device is started, and a data range which can be taken when there is no malfunction is usually Derived as a range of

  Then, during the operation of the combustion apparatus, the ignition delay time Td in the ignition sequence, the consumption current Ic of the ignition device, the frame voltage VF, the air flow rate FA, and the fuel flow rate FF are measured, and the ignition delay time Td in the measured ignition sequence When any one of the consumption current Ic of the igniter, the frame voltage VF, the air flow rate FA, and the fuel flow rate FF is within the normal range but deviates from the normal range, it is determined that the combustion device has a malfunction.

For example, an average value of the ignition delay times Td that are repeatedly measured is set as a reference ignition delay time TdB (see FIG. 1), and a predetermined range centered on the reference ignition delay time TdB is set as a normal range. And although the measured ignition delay time Td is within the normal range (TdE _L <Td, Td <TdE _H ), the combustion device has malfunctioned when it deviates from the normal range (Td L ≦ Td ≦ TdH) Determine that there is.

TdE _L and TdE _H are threshold values for determining abnormality, TdE _L is set shorter than the lower limit side value TdL of the normal range, and TdE _H is higher than the upper limit side value TdH of the normal range It is set long. Further, the reference ignition delay time TdB may not be an average value of the measured ignition delay times Td, but may be determined as an initial value at the start of operation.

  Also, in this example, the frame voltage VF is measured according to the flame intensity detected by the flame detector. However, the frame current IF is measured, and determination of malfunction is performed similarly to the frame voltage VF. You may do so.

[Outline of Embodiment 2]
In the second embodiment, the flame voltage VF, the air flow rate FA, the fuel flow rate FF, the degree of opening of the control motor (the amount of air and fuel supplied to the combustion chamber are adjusted during the steady combustion sequence) every time the combustion device is operated. Measurement of the damper opening θ) is repeated, and a data range that can be taken when there is no malfunction of the frame voltage VF, the air flow rate FA, and the fuel flow rate FF for each opening θ of the control motor is derived as a normal range.

  Then, during operation of the combustion apparatus, the frame voltage VF, the air flow rate FA, and the fuel flow rate FF in the steady combustion sequence are measured in association with the opening degree θ of the control motor, and are measured in correspondence with the opening degree θ of the control motor When any one of the frame voltage VF, the air flow rate FA, and the fuel flow rate FF in the steady combustion sequence falls within the normal range but deviates from the normal range, it is determined that the combustion apparatus is malfunctioning.

For example, an average value of the frame voltage VFθ at the opening degree θ of the control motor measured repeatedly is set as a reference frame voltage VFθB (see FIG. 2), and a predetermined range centered on the reference frame voltage VFθB is set as a normal range. Then, within the measured frame voltage VFshita is normal _{(VFθE L <VFθ, VFθ <} VFθE H) there are in, when not depart from the normal range (VFθL ≦ VFθ ≦ VFθH), there is a malfunction in the combustion device It is determined that

Incidentally, VFθE _L, a threshold for VFshitaE _H is to determine an abnormality, VFθE _L is set smaller than the normal lower limit values VFθL range, VFθE _H rather than the normal range upper limit value VFθH of It is set large. Further, the reference frame voltage VFθB may not be an average value of the measured frame voltages VFθ, but may be determined as an initial value at the start of operation.

  Further, in this example, the frame voltage VFθ at the opening degree θ corresponding to the flame intensity detected by the flame detector is measured, but the frame current IFθ at the opening degree θ is measured, The malfunction may be determined similarly to the frame voltage VFθ at the time of degree θ.

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, "start check", "pre-purge", "wait for ignition", "pilot ignition (ignition sequence)", "pilot only", "main ignition", and the like from the start of the combustion apparatus 22 to the steady combustion. Each combustion sequence is defined as "main stable" or "steady 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 operating, that is, the period P4 from the point t6 to the point t7 shown in FIG. 5 (h) is a time zone of "pilot ignition (ignition sequence)". The period P5 up to 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 a lapse of time S4 which is the sum of the main ignition time and the main stabilization time (see FIG. Transition to steady-state combustion at t10 point shown in 5 (d). Of the period from t8 to t10, period P6 from t8 to t9 is the "main ignition" time period, and period P7 from t9 to t10 is the "main stable" time period. There is a period P8 after t10, which is a time zone of "steady combustion (steady 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.

First Embodiment
In FIG. 6, the functional block diagram of the principal part of the combustion control apparatus 2 in Embodiment 1 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 Flow FF), an air flow rate of the air flow meter 21 measures (air flow FA), as combustion control information such as opening θ of the control motor M, 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. Further, the combustion control device 2 measures an ignition delay time Td from the start of ignition of the pilot burner 7 to the strength of the flame detected by the flame detector 9 until it is determined that the flame is present. Further, the consumption current Ic of the ignition device 8 is measured. 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 an misfire, information indicating a extinguishment, a frame voltage VF, and an ignition delay time. Td, the consumption current Ic of the ignition device 8 and the like are also included.

  The malfunction determination unit 2-2 includes an ignition sequence determination unit 2-21 that determines whether the combustion device 22 is in the ignition sequence. The ignition sequence determination unit 2-21 determines whether or not the combustion device 22 is in the ignition sequence (period P4 shown in FIG. 5) based on the combustion control information collected by the combustion control information collection unit 2-1. .

  If the malfunction determination unit 2-2 determines that the ignition sequence is in progress (YES in step S101 shown in FIG. 7), the ignition delay time Td, the consumed current Ic of the ignition device 8, and the frame are used as combustion control information in the ignition sequence. The voltage VF, the air flow rate FA, and the fuel flow rate FF (measured value) are acquired from the combustion control information collection unit 2-1 (steps S102 to S106).

  Then, the malfunction determining unit 2-2 determines that the ignition delay time Td in the ignition sequence, the consumption current Ic of the ignition device 8, the frame voltage VF, the air flow rate FA, and the fuel flow rate FF are normally determined in advance. If it is out of the normal state but within the above range, it is determined that the combustion device 22 is in a malfunctioning state (step S107).

  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]
The malfunction determination unit 2-2 determines that any one of the ignition delay time Td in the ignition sequence, the consumption current Ic of the ignition device 8, the frame voltage VF, the air flow rate FA, and the fuel flow rate FF is within a predetermined normal range. However, if it deviates from the normal state, it is determined that the combustion device 22 is in a malfunctioning state. Hereinafter, the process performed by the malfunction determination unit 2-2 will be described in more detail.

  FIG. 8 shows a time chart during the ignition sequence at the normal time. Fig. 8 (a) is "power supply", Fig. 8 (b) is "start input", Fig. 8 (c) is "wind pressure switch" and Fig. 8 (d) is "flame signal (signal indicating presence or absence of flame)" 8 (e): “frame voltage VF”, FIG. 8 (f): “fuel flow FF”, FIG. 8 (g): “air flow FA”, FIG. 8 (h): “ignition (ignition transformer)” 8 (i) shows a time chart of "blower".

  When the frame voltage VF exceeds the predetermined value VFth (t2 point shown in FIG. 8E) after the ignition is turned on (t1 point shown in FIG. 8H), it is determined that there is a flame. The time from when the ignition is turned on to when it is determined that the flame is present is measured as an ignition delay time Td.

  FIG. 9 shows a diagram corresponding to FIG. 8 when the fuel flow rate FF is reduced. FIG. 10 shows a diagram corresponding to FIG. 8 when the air flow rate FA is excessive. In the example shown in FIG. 9, as the waveform of the fuel flow rate FF in the normal state is shown by a dotted line (FIG. 9 (f)), the fuel flow rate FF in the ignition sequence is decreasing. In the example shown in FIG. 10, as the waveform of the air flow rate FA at the normal time is shown by a dotted line (FIG. 10 (g)), the air flow rate FA in the ignition sequence is increasing.

[Ignition delay time Td]
The malfunction determination unit 2-2 includes an upper limit time TdH and a lower limit time TdL that define the normal range derived as described above with reference to FIG. 1 with respect to the ignition delay time Td. The time TdE _L and TdE _H for determining whether it is normal or abnormal is set.

  If the ignition delay time Td is TdL ≦ Td ≦ TdH (YES in step S201 shown in FIG. 11), the malfunction determination unit 2-2 determines that the ignition delay time Td is normal (step S203).

If the ignition delay time Td does not satisfy TdL ≦ Td ≦ TdH (NO in step S201), the malfunction determination unit 2-2 determines that the ignition delay time Td is within the normal range (TdE _L <Td, Td <TdE _H ). It is confirmed whether there is any (step S202).

  If the ignition delay time Td is not within the normal range (NO in step S202), the malfunction determination unit 2-2 determines that the ignition delay time Td is abnormal (step S204), and the ignition delay time Td is normal. If it is within the range (YES in step S202), it is determined that the ignition delay time Td is malfunctioning (step S205).

[Current consumption Ic]
In the malfunction judging unit 2-2, with respect to the consumption current Ic of the ignition device 8, the consumption current IcH on the upper limit side and the consumption current IcL on the lower limit side defining the normal range derived similarly to the ignition delay time Td. Consumption currents IcE _L and IcE _H for determining whether normal or abnormal are set.

  If the consumption current Ic of the ignition device 8 is IcL ≦ Ic ≦ IcH (YES in step S301 shown in FIG. 12), the malfunction determination unit 2-2 determines that the consumption current Ic of the ignition device 8 is normal ( Step S303).

If the consumed current Ic of the ignition device 8 does not satisfy IcL ≦ Ic ≦ IcH (NO in step S301), the malfunction determination unit 2-2 determines that the consumed current Ic of the ignition device 8 is within the normal range (IcE _L <Ic, It is checked whether or not Ic <IcE _H ) (step S302).

  If the consumption current Ic of the ignition device 8 is not within the normal range (NO in step S302), the malfunction determination unit 2-2 determines that the consumption current Ic of the ignition device 8 is abnormal (step S304), and ignition is performed. If the consumption current Ic of the device 8 is within the normal range (YES in step S302), it is determined that the consumption current Ic of the ignition device 8 is malfunctioning (step S305).

[Frame voltage VF]
In the malfunction judging unit 2-2, the frame voltage VFH on the upper limit side and the frame voltage VFL on the lower limit side defining the normal range derived similarly to the ignition delay time Td with respect to the frame voltage VF, and normality or abnormality The frame voltages VFE _L and VFE _H for determining whether or not are set.

  If the frame voltage VF is VFL ≦ VF ≦ VFH (YES in step S401 shown in FIG. 13), the malfunction determination unit 2-2 determines that the frame voltage VF is normal (step S403).

If the frame voltage VF is not VFL ≦ VF ≦ VFH (NO in step S401), the malfunction determination unit 2-2 determines whether the frame voltage VF is in a normal range (VFE _L <VF, VF <VFE _H ) It is confirmed whether or not it is (step S402).

  If the frame voltage VF is not within the normal range (NO at step S402), the malfunction determination unit 2-2 determines that the frame voltage VF is abnormal (step S404), and the frame voltage VF is within the normal range. If there is (YES in step S402), it is determined that the frame voltage VF is malfunctioning (step S405).

[Air flow rate FA]
In the malfunction judging unit 2-2, the upper-limit air flow FAH and the lower-limit air flow FAL defining the normal range derived similarly to the ignition delay time Td with respect to the air flow FA, and normality or abnormality Air flow rates FAE _L and FAE _H are set to determine whether the air flow rate is high or low.

  If the air flow rate FA is FAL ≦ FA ≦ FAH (YES in step S501 shown in FIG. 14), the malfunction determination unit 2-2 determines that the air flow rate FA is normal (step S503).

Or air when the flow rate FA is not a FAL ≦ FA ≦ FAH (NO in step S501), malfunction determining unit 2-2 is in the range air flow FA is normal _{(FAE L <FA, FA <} FAE H) It is confirmed whether or not it is (step S502).

  If the air flow rate FA is not within the normal range (NO at step S502), the malfunction determination unit 2-2 determines that the air flow rate FA is abnormal (step S504), and the air flow rate FA is within the normal range. If there is (YES in step S502), it is determined that the air flow rate FA is malfunctioning (step S505).

In the example shown in FIG. 10, the air flow FA in the ignition sequence becomes excessive, in step S502 passing through the step S501, _{"FAE L <FA, FA <FAE} H " If it is confirmed that the air flow FA Is determined to be malfunctioning.

[Fuel flow FF]
In the malfunction determination unit 2-2, the upper limit side fuel flow rate FFH and the lower limit side fuel flow rate FFL defining the normal range derived similarly to the ignition delay time Td with respect to the fuel flow rate FF, and normality or abnormality The fuel flow rates FFE _L and FFE _H are set to determine the fuel flow rate.

  If the fuel flow rate FF is FFL ≦ FF ≦ FFH (YES in step S601 shown in FIG. 15), the malfunction determination unit 2-2 determines that the fuel flow rate FF is normal (step S603).

If the fuel flow rate FF is not FFL ≦ FF ≦ FFH (NO in step S601), the malfunction determination unit 2-2 determines whether the fuel flow rate FF is within the normal range (FFE _L <FF, FF <FFE _H ) It is confirmed whether or not it is (step S602).

  If the fuel flow rate FF is not within the normal range (NO at step S602), the malfunction determination unit 2-2 determines that the fuel flow rate FF is abnormal (step S604), and the fuel flow rate FF is within the normal range. If there is (YES in step S602), it is determined that the fuel flow rate FF is malfunctioning (step S605).

In the example shown in FIG. 9, if the fuel flow rate FF in the ignition sequence decreases and it is confirmed that “FFE _L <FF, FF <FFE _H ” in step S 602 after step S 601, the fuel flow rate FF Is determined to be malfunctioning.

  If the malfunction determining unit 2-2 determines that any of the ignition delay time Td in the ignition sequence, the consumption current Ic of the ignition device 8, the frame voltage VF, the air flow rate FA, and the fuel flow rate FF is malfunctioning, the combustion device 22 malfunctions. It judges that it is in the state, sends the judgment result to the monitoring device 23 through the output unit 2-3, and displays it on the monitoring screen of the monitoring device 23.

  In this case, on the monitoring screen of the monitoring device 23, any one of the ignition delay time Td, the consumption current Ic of the ignition device 8, the frame voltage VF, the air flow rate FA, and the fuel flow rate FF is known to be malfunctioning. That is, it is notified that the combustion device 22 is in a state of malfunction, in such a manner that the item determined to be malfunction is known.

  Also in the case where any one of the ignition delay time Td in the ignition sequence, the consumption current Ic of the ignition device 8, the frame voltage VF, the air flow rate FA, and the fuel flow rate FF is determined abnormal in the malfunction determination unit 2-2 In the same way as when it is determined that the combustion device 22 is in an abnormal state, it is notified.

Second Embodiment
In FIG. 16, the functional block diagram of the principal part of the combustion control apparatus 2 in Embodiment 2 is shown. Hereinafter, in order to distinguish from the combustion control device 2 (FIG. 6) in the first embodiment, the combustion control device 2 in the first embodiment is 2A, and the combustion control device 2 in the second embodiment is 2B.

  In the combustion control device 2B, the malfunction determination unit 2-2 includes a steady combustion sequence determination unit 2-22 that determines whether the combustion device 22 is in a steady combustion sequence. Based on the combustion control information collected by the combustion control information collection unit 2-1, the steady-state combustion sequence determination unit 2-22 determines whether the combustion device 22 is in the steady-state combustion sequence (period P7 shown in FIG. 5). to decide.

  If the malfunction determination unit 2-2 determines that the steady combustion sequence is in progress (YES in step S701 shown in FIG. 17), the current opening degree θ of the control motor M is set as the combustion control information in the steady combustion sequence. The frame voltage VFθ at the time of θ, the air flow rate FAθ at the opening degree θ, and the fuel flow rate FFθ (measurement value) at the opening degree θ are acquired from the combustion control information collecting unit 2-1 (steps S702 to S705).

  Then, the malfunction judging unit 2-2 determines that any one of the frame voltage VFθ, the air flow rate FAθ, and the fuel flow rate FFθ at the opening degree θ in this steady-state combustion sequence is normally within a predetermined normal range. If it is determined that the combustion apparatus 22 is out of state, it is determined that the combustion apparatus 22 is in a malfunctioning state (step S706). Hereinafter, the process performed by the malfunction determination unit 2-2 will be described in more detail.

[Frame voltage VFθ at opening θ]
With respect to the frame voltage VFθ at the opening degree θ, the frame voltage VFθH on the upper limit side defining the normal range derived as described above with reference to FIG. and frame voltage VFθL of the frame voltage for determining whether normal or abnormal VFshitaE _L, and a VFshitaE _H are set.

  If the frame voltage VFθ at the opening degree θ is VFθL ≦ VFθ ≦ VFθH (YES at step S801 shown in FIG. 18), the malfunction determining unit 2-2 determines that the frame voltage VFθ at the opening degree θ is normal. (Step S803).

If the frame voltage VFθ at the opening degree θ does not satisfy VFθL ≦ VFθ ≦ VFθH (NO in step S801), the malfunction determination unit 2-2 determines that the frame voltage VFθ at the opening degree θ is within the normal range (VFθE _L < It is checked whether or not VFθ, VFθ <VFθE _H ) (step S802).

  If the frame voltage VFθ at the opening degree θ is not within the normal range (NO at step S802), the malfunction determining unit 2-2 determines that the frame voltage VFθ at the opening degree θ is abnormal (step S804) If the frame voltage VFθ at the opening degree θ is within the normal range (YES in step S802), it is determined that the frame voltage VFθ at the opening degree θ is malfunctioning (step S805).

[Air flow rate FAθ at opening θ]
In the malfunction judgment unit 2-2, the upper limit air flow rate FAθH and the lower limit side defining a normal range derived similarly to the frame voltage VFθ at the opening degree θ with respect to the air flow rate FAθ at the opening degree θ and air flow rate FAθL of air flow FAshitaE _L for determining the normal or abnormal, and a FAshitaE _H are set.

  If the air flow rate FAθ at the opening degree θ is FAθL ≦ FAθ ≦ FAθH (YES in step S901 shown in FIG. 19), the malfunction determining unit 2-2 determines that the air flow rate FAθ at the opening degree θ is normal. (Step S903).

If the air flow rate FAθ at the opening degree θ is not FAθL ≦ FAθ ≦ FAθH (NO in step S901), the malfunction determination unit 2-2 determines that the air flow rate FAθ at the opening degree θ is within the normal range (FAθE _L < It is checked whether or not FAθ, FAθ <FAθE _H ) (step S 902).

  If the air flow rate FAθ at the opening degree θ is not within the normal range (NO at step S902), the malfunction determining unit 2-2 determines that the air flow rate FAθ at the opening degree θ is abnormal (step S904) If the air flow rate FAθ at the opening degree θ is within the normal range (YES in step S902), it is determined that the air flow rate FAθ at the opening degree θ is malfunctioning (step S905).

[Fuel flow FFθ at opening θ]
In the malfunction judgment unit 2-2, the fuel flow at the upper limit side θ defines the normal range derived similarly to the frame voltage VFθ at the opening θ with respect to the fuel flow rate FFθ at the opening θ a fuel flow FFθL when flow FFθH and opening of the lower side theta, normal or abnormal or fuel flow FFshitaE _L when opening theta for determining, and a FFshitaE _H are set.

  If the fuel flow rate FFθ at the opening degree θ is FFθL ≦ FFθ ≦ FFθH (YES at step S1001 shown in FIG. 15), the malfunction determining unit 2-2 determines that the fuel flow rate FFθ at the opening degree θ is normal. (Step S1003).

If the fuel flow rate FFθ at the opening degree θ does not satisfy FFθL ≦ FFθ ≦ FFθH (NO in step S1001), the malfunction determination unit 2-2 determines that the fuel flow rate FFθ at the opening degree θ is within the normal range (FFθE _L < It is checked whether or not FFθ, FFθ <FFθE _H ) (step S1002).

  If the fuel flow rate FFθ at the opening degree θ is not within the normal range (NO at step S1002), the malfunction determination unit 2-2 determines that the fuel flow rate FFθ at the opening degree θ is abnormal (step S1004) If the fuel flow rate FFθ at the opening degree θ is within the normal range (YES in step S1002), it is determined that the fuel flow rate FFθ at the opening degree θ is malfunctioning (step S1005).

  The malfunction determining unit 2-2 determines that the combustion device 22 is in a malfunctioning state when it determines that any of the frame voltage VFθ, the air flow rate FAθ, and the fuel flow rate FFθ at the opening degree θ during steady combustion is malfunctioning. 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 possible to know which one of the frame voltage VFθ, the air flow rate FAθ and the fuel flow rate FFθ at the opening degree θ is malfunctioning, that is, the item determined to be malfunctioning In this way, it is notified that the combustion device 22 is in a malfunctioning state.

  Also in the case where the malfunction determination unit 2-2 determines that the flame voltage VFθ, the air flow rate FAθ, or the fuel flow rate FFθ at the opening degree θ during steady combustion is abnormal, the same manner as when it is determined that malfunction occurs. , To notify that the combustion device 22 is in an abnormal state

  Thus, in the present embodiment (Embodiments 1 and 2), it is possible to early know that the combustion apparatus 22 is in a normal but malfunctioning state before reaching an abnormality. become. 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 item 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. 21, a transmission unit 2-4 is provided in the combustion control device 2, and the monitoring device (remote monitoring device) 23 at a remote place is judged to be out of order via 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.

[Data retention (playback of ignition)]
In the embodiment described above, the combustion control device 2 has a function of acquiring and storing data separately from determining malfunction of the combustion device 22 as in the ignition sequence or in the steady combustion sequence. Data can be taken out to communication or an external memory, and can be an object of data analysis by visual observation or a personal computer (PC).

[External data measurement]
In the embodiment described above, a device for measuring data may be provided outside the combustion control device 2. That is, output information of "fuel valve" and "ignition device", time series data of "frame voltage" and "flame detection signal" by the combustion control device 2, "fuel flow rate" and "air flow rate" from various flowmeters, temperature controller A device for measuring data that receives and stores “temperature in the furnace” or the like may be provided outside. In this case, in the data measurement device, in order to synchronize time axis of each data, the synchronization signal is output from the combustion control device 2 to synchronize time with other measuring instrument data such as flow meter, temperature controller and the like. Take. The synchronization signal may be in the form of communication command, digital I / O output or the like.

[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 (2A, 2B) ... combustion control apparatus, 2-1 ... combustion control information collection part, 2-2 ... malfunction determination part, 2-21 ... ignition sequence judgment part, 2-22 ... steady combustion sequence Judgment part, 2-3 ... output part, 3 ... fuel flow path, 4 ... air flow path, 5 ... combustion chamber, 6 ... main burner, 7 ... pilot burner, 8 ... igniter (ignition), 9 ... flame detector 11-14 Safety shut-off valve 15 Gas pressure switch 16 Blower 17 Wind pressure switch (air flow switch) 18 Air flow adjustment damper 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 (3)

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 combustion control information collecting unit configured to collect, as the combustion control information, information of a predetermined monitoring item during control of the operation of the combustion device by the combustion control device;
A malfunction configured to determine whether or not the combustion device is in a normal range but in a malfunctioning state deviated from a normal state based on the combustion control information in a predetermined sequence in the combustion sequence. And a determination unit. In the combustion system according to claim 1,
An igniter configured to ignite a burner of the combustor;
And a flame detector configured to detect the flame intensity of the burner,
The combustion control information collection unit
As the combustion control information in the predetermined sequence, an ignition delay time from the start of ignition to the burner to the intensity of the flame detected by the flame detector in the ignition sequence to the determination that the flame is present, the ignition Collecting at least one of a current consumption of a device, a flame intensity detected by the flame detector, a flow rate of air to the combustion chamber, and a flow rate of fuel gas to the combustion chamber;
The malfunction judging unit
The ignition delay time in the ignition sequence collected by the combustion control information collection unit, the consumed current of the ignition device, the flame intensity detected by the flame detector, the flow rate of air to the combustion chamber, the combustion If any one of the flow rates of the fuel gas to the chamber is within a predetermined normal range but deviates from the normal state, it is determined that the combustion device is in a malfunctioning state. Combustion system. In the combustion system according to claim 1,
A damper configured to adjust the supply of air and fuel to the combustion chamber;
A flame detector configured to detect the flame intensity of the burner of the combustion device;
The combustion control information collection unit
The combustion control information in the predetermined sequence includes the intensity of the flame detected by the flame detector, the flow rate of air to the combustion chamber, and the flow rate of fuel gas to the combustion chamber in a steady combustion sequence. Collecting at least one in correspondence with the opening degree of the damper;
The malfunction judging unit
The flame intensity detected by the flame detector in the steady-state combustion sequence collected corresponding to the opening degree of the damper by the combustion control information collecting unit, the flow rate of air to the combustion chamber, the combustion chamber If any one of the fuel gas flow rates is within the normal range defined for each opening of the damper but deviates from the normal state, it is determined that the combustion device is in the malfunctioning state A combustion system characterized by