JP2015161427A - Boiler equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide boiler equipment in which efficiency of a boiler can be increased by optimally controlling the combustion amount of the boiler.SOLUTION: Boiler equipment 1 is provided which comprises: a boiler 2 having a combustion region that is divided into a plurality of combustion zones; a steam pressure detection part 3 for detecting the steam pressure in the boiler 2; and a control part 4 for controlling the combustion state of the boiler, depending on the steam pressure detected by the steam pressure detection part 3. The control part 4 includes: a set part 41 for setting each of the plurality of combustion zones to a stage value control region where the combustion amount is gradually changed or a consecutive control region where the combustion amount is consecutively changed,; a stage value control part 42 for combusting the boiler in the combustion zone set to the stage value control region at a prescribed combusting rate set in advance corresponding to the combustion zone; and a continuous control part 43 for combusting the boiler in the combustion zone set to the consecutive control region in such a way that the steam pressure to be detected by the steam pressure detection part becomes the set target pressure set in advance corresponding to the combustion zone.

Description

  The present invention relates to a boiler device capable of integrating continuous control and step value control by a proportional control method.

  Conventionally, in a boiler system that generates steam by burning a plurality of boilers, the number of combustion boilers and the combustion amount are calculated so that the steam pressure becomes a target value, and the combustion amount of the target boiler is increased or decreased. A technology related to boiler control is disclosed (for example, see Patent Document 1).

  Further, the boilers are roughly classified into a step value control boiler that can increase and decrease the combustion amount stepwise according to the selected combustion position and a proportional control boiler that can continuously increase and decrease the combustion amount (for example, Patent Document 2). In a boiler system including a plurality of boilers, one or both of a step value control boiler and a proportional control boiler are appropriately used according to required performance, cost, and the like.

JP 2002-130602 A JP 2010-43768 A

By the way, the step value control boiler is excellent in terms of responsiveness by being able to adjust the combustion amount in stages, but, for example, in the case of three-position control (high combustion, low combustion, combustion stop), low combustion Therefore, there is a problem in terms of pressure stability because the pressure fluctuation range becomes large.
Conversely, the proportional control boiler is excellent in terms of pressure stability because it can continuously increase and decrease the amount of combustion, but there is a problem in terms of responsiveness.

  For this reason, in a boiler having a combustion region divided into a plurality of regions, step value control is applied to a combustion region where priority is given to responsiveness, and continuous control is applied to a combustion region where priority is given to pressure stability. By applying this, a boiler that can utilize the pressure stability of continuous control and the responsiveness of step value control at the right place in the right place is desired.

  An object of the present invention is to provide a boiler that can be divided into a plurality of combustion regions according to a combustion rate, and that can apply continuous control or step value control to each combustion region.

  The present invention relates to a boiler having a combustion region divided into a plurality of parts, a steam pressure detecting unit for detecting a steam pressure in the boiler, and a combustion state of the boiler according to the steam pressure detected by the steam pressure detecting unit. And a control unit that controls the boiler unit, wherein the control unit continuously changes the combustion amount in a step value control region in which the combustion amount is changed in a stepwise manner, or a combustion amount. A setting unit configured to set a continuous control region; a stage value control unit configured to burn the boiler at a combustion rate set in advance corresponding to the combustion region in the combustion region set to the step value control region; In the combustion region set in the control region, the boiler is burned so that the steam pressure detected by the steam pressure detection unit becomes a target pressure set in advance corresponding to the combustion region. And parts relates to a boiler apparatus comprising a.

  Further, the control by the continuous control unit can be switched to the control by the step value control unit in accordance with a predetermined change in the steam pressure detected by the vapor pressure detection unit.

  Further, the control by the step value control unit can be switched to the control by the continuous control unit according to a predetermined change in the steam pressure detected by the vapor pressure detection unit.

  Moreover, the said boiler can be set as a step value control boiler by setting all the said some combustion area to a step value control area | region by the said setting part.

  Moreover, the said boiler can be set as a proportional control boiler by setting all the said some combustion area to a continuous control area | region by the said setting part.

  According to the present invention, in a boiler having a combustion region divided into a plurality of regions, the step value control is applied to the combustion region in which priority is given to responsiveness, and the combustion region in which pressure stability is preferred to be given priority. By applying continuous control, it is possible to use the stability of continuous control and the responsiveness of step value control in the right place.

1 is a diagram illustrating a schematic configuration of a boiler device 1 according to an embodiment of the present invention. It is a functional block diagram which shows the structure of the control part 4 which concerns on embodiment of this invention. It is a figure which shows the combustion area | region divided | segmented into plurality (five pieces) of the boiler apparatus 1 which concerns on embodiment of this invention. Among the combustion regions divided into a plurality (five) of the boiler device 1 according to the embodiment of the present invention, some combustion regions are set as step value control regions, and other combustion regions are set as continuous control regions. It is a figure which shows one Example of the boiler apparatus 1 set. It is a figure which shows one Example of the boiler apparatus 1 by which all the combustion areas of the combustion area divided | segmented into plurality (five pieces) of the boiler apparatus 1 which concerns on embodiment of this invention are set to the step value control area | region. The combustion region of the combustion region divided into a plurality (five) of the boiler device 1 according to the embodiment of the present invention includes a combustion stop state S0 and a minimum combustion state S1 (combustion state with a combustion rate of 20%) to a maximum combustion state S2. It is a figure which shows one Example of the boiler apparatus 1 set so that a combustion rate became controllable continuously in the range of (the combustion state of 20% of combustion rates). Among combustion regions divided into a plurality of boiler devices 1 according to the embodiment of the present invention, some combustion regions are set as step value control regions, and other combustion regions are set as continuous control regions. It is a figure which shows the relationship between a steam pressure value and a combustion area | region in a case. It is a figure which shows the relationship between a steam pressure value and the combustion area | region in case all the combustion areas divided | segmented into plurality of the boiler apparatus 1 which concern on embodiment of this invention are set to the step value control area | region.

Hereinafter, with reference to FIG. 1, the boiler apparatus 1 which concerns on one Embodiment of this invention is demonstrated. FIG. 1 is a diagram showing a schematic configuration of a boiler apparatus 1 according to an embodiment of the present invention.
As shown in FIG. 1, the boiler device 1 includes a boiler 2 having a burner and a blower for supplying combustion air (both not shown), and the boiler 2 has a minimum combustion state, for example, from a combustion rate of 20%. 100% continuous combustion is possible, and it can be divided into a plurality of combustion regions according to the combustion rate, and continuous control or step value control can be applied to each combustion region.

In addition, the boiler device 1 includes a vapor pressure detection unit 3 that detects a vapor pressure in a can (not shown) in order to calculate a necessary vapor amount required for the boiler 2.
Moreover, the boiler apparatus 1 is provided with the control part 4 which controls the combustion state of the boiler 2 according to the steam pressure in the can detected by the steam pressure detection part 3.

  As shown in FIG. 2, the control unit 4 converts each combustion region of the plurality of combustion regions into a step value control region in which the combustion amount is changed stepwise or a continuous control region in which the combustion amount is continuously changed. A setting unit 41 to be set, a stage value control unit 42 for burning the boiler at a preset combustion rate corresponding to the combustion region in the combustion region set to the step value control region, and a continuous control region And a continuous control unit 43 that burns the boiler so that the steam pressure detected by the steam pressure detection unit 3 becomes a preset target pressure set in advance corresponding to the combustion region.

The boiler apparatus 1 of this embodiment can supply the steam generated by the boiler 2 to the steam using facility.
The boiler apparatus 1 measures the pressure P of the steam in the boiler apparatus 1 to be controlled by the steam pressure detection unit 3, and based on the measured pressure, the step value control unit 42 or the continuous control unit 43 determines the boiler 2. The amount of combustion is controlled.

  The step value control unit 42 controls the boiler 2 at a combustion position (combustion rate) set in advance in the combustion region set in the step value control region according to the steam pressure in the can detected by the steam pressure detection unit 3. It is designed to burn.

  The continuous control unit 43 is configured so that in the combustion region set in the continuous control region, the vapor pressure in the can detected by the vapor pressure detection unit 3 becomes a target pressure set in advance corresponding to the combustion region. The boiler 2 is continuously burned within a predetermined combustion rate range, for example, in the combustion region.

<Control by continuous control unit>
Here, the control by the continuous control unit 43 will be outlined.
The continuous control unit 43 continuously moves the boiler 2 in the combustion region so that the vapor pressure in the can detected by the vapor pressure detection unit 3 becomes a preset target pressure corresponding to the combustion region. Control to burn.

  The continuous control unit 43 adjusts the amount of steam generated by changing the combustion rate of the boiler 2 in accordance with the amount of steam consumed by the load equipment to which the boiler 2 supplies steam. Here, the demand load (steam consumption) increases due to an increase in demand for load equipment, and the amount of steam supplied to the load equipment, that is, the amount of steam generated from the boiler 2 (hereinafter also referred to as “output steam amount”) is insufficient This will reduce the vapor pressure in the can. On the other hand, if the demand load (steam consumption) decreases due to a decrease in demand for load equipment and the amount of steam supplied into the can becomes excessive, the steam pressure in the can increases. Therefore, the continuous control unit 43 can monitor the fluctuation of the required load based on the fluctuation of the vapor pressure measured by the vapor pressure detection unit 3. And the continuous control part 43 can detect the excess and deficiency of a vapor | steam quantity by comparing the preset target pressure and the vapor | steam pressure in a can.

  The continuous control unit 43 performs the feedback control based on the PI algorithm or the PID algorithm on the deviation between the target pressure set in advance according to the load device and the steam pressure in the can, so that the steam pressure in the can is reduced. The amount of steam (amount of operation) required to reach the target pressure is calculated, and the combustion state of the boiler 2 is controlled so that the calculated amount of steam is output from the boiler 2.

  The continuous control unit 43 calculates the necessary steam amount by, for example, a speed-type PID algorithm so that the steam pressure value PV in the can measured by the steam pressure detection unit 3 becomes a preset target steam pressure value SV. To do.

The continuous control unit 43 calculates the current required steam amount MVn generated from the boiler 2 based on, for example, the following speed type arithmetic expression (1).

MV _n = MV _n-1 + ΔMV _n (1)
Here, when Δt is a control period and n is a positive integer value,
MV _n is the current required steam amount generated from the plurality of boilers 20 in the control cycle n (starting point t0 + n * Δt),
MV _n-1 is the previous required steam amount in the control cycle (n-1),
ΔMV _n represents the required amount of steam change for each control cycle.

The speed type calculation is a method of calculating only the necessary steam amount change ΔMV _{n for} each control cycle and adding the previous required steam amount MV _n−1 to this to calculate the present required steam amount MV _n .
On the other hand, the PID control algorithm that directly calculates the required steam amount MV _n this time for each control cycle is referred to as position calculation.

The required steam amount change ΔMV _{n for} each control cycle is calculated based on the following equations (2) to (6).

ΔMV _n = ΔP _n + ΔI _n + ΔD _n (2)
Here, ΔP _n is the P control output (change).
[Delta] I _n the I control output (change amount),
ΔD _n represents the D control output (change).

_{* ΔP n = K P (e} n -e n-1) ··· (3)
Where K _P is the proportional gain,
e _n, as shown in equation (4), the difference (time difference of the current and target steam pressure value SV _n, the current steam pressure value PV _n of internal steam header 6 measured by vapor pressure detector 3 Amount).

e _n = SV _n −PV _n (4)

_{ΔI n = K P * (Δt} / T I) * e n ··· (5)
T _I represents the integration time.

_{ΔD n = K P * (T} D / Δt) * (e n -2e n-1 + e n-2)
... (6)
Here, _{T D} represents the derivative time.

The continuous control unit 43 calculates the necessary steam amount change ΔMV _n for each control cycle by summing the outputs (changes) calculated by the equations (3), (5), and (6).
The continuous control unit 43 adds ΔMV _n to the previous required steam amount MV _n−1 and calculates the current required steam amount MV _n as shown in Expression (1).
Note that the continuous control unit 43 may apply a PID control algorithm based on a position type calculation when calculating the required steam amount.

The continuous control unit 43 controls the combustion state (combustion amount) of the boiler 2 so that steam corresponding to the required steam amount is generated from the boiler 2 based on the required steam amount this time.
In this way, if the steam consumption by the load device to which the boiler 2 supplies steam does not fluctuate abruptly, the continuous control unit 43 follows the fluctuation of the steam consumption and the output steam amount corresponding to the required steam amount. Can be output.

  Hereinafter, about the boiler apparatus 1, when several combustion areas are set to a step value control area | region among the combustion areas divided | segmented into plurality, other combustion areas are set to a continuous control area (henceforth, (Sometimes referred to as “step value / continuous control setting”), when all combustion regions are set as step value control regions (hereinafter also referred to as “step value control settings”), and when all combustion regions are Each case where the continuous control area is set (hereinafter sometimes referred to as “continuous control setting”) will be described.

<Step value / continuous control setting>
First, among the divided combustion regions, some combustion regions are set as step value control regions and other combustion regions are set as continuous control regions (step value / continuous control setting). ) Will be described with reference to FIGS. 3B and 4.

In FIG. 3B, among the combustion regions divided into a plurality (five) as shown in FIG. 3A, some combustion regions are set as step value control regions and other combustion regions are set as continuous control regions. It is a figure which shows one Example of the boiler apparatus 1 which is.
As shown in FIG. 3B, each combustion region is set as follows.
In addition, about the combustion rate 0% (combustion stop), it has named the 1st combustion area | region A1 for convenience.

(1) First combustion region A1 (combustion rate 0%) That is, combustion is stopped.
(2) The second combustion region A2 (0% <burning rate ≦ 20%) is set in the step value control region (burning rate 20%).
(3) The third combustion region A3 (20% <combustion rate ≦ 30%) is set in the step value control region (combustion rate 30%).
(4) The fourth combustion region A4 (30% <combustion rate ≦ 60%) is set in the continuous control region.
Note that the continuous control in the fourth combustion region A4 (30% <combustion rate ≦ 60%) is based on a preset target vapor pressure SV4, for example, a combustion amount in a range from a combustion rate of 30% to a combustion rate of 60%. Is controlled to be continuously increased or decreased.
(5) The fifth combustion region A5 (60% <combustion rate ≦ 75%) is set to the step value control region (combustion rate 75%).
(6) The sixth combustion region A6 (75% <combustion rate ≦ 100%) is set in the continuous control region.
Note that the continuous control in the sixth combustion region A6 (75% <combustion rate ≦ 100%) is based on the preset target vapor pressure SV6, for example, the combustion amount in the range from the combustion rate 75% to the combustion rate 100%. It shall be controlled so that it can be increased or decreased continuously.

  As in the embodiment of FIG. 3C, when the fourth combustion region A4 (30% <burning rate ≦ 60%) is set in the step value control region, control is performed with a combustion rate of 30% and a combustion rate of 60%. Although the pressure fluctuation range becomes large and there is a problem in terms of pressure stability, as in the embodiment of FIG. 3B, by setting the fourth combustion region A4 (30% <combustion rate ≦ 60%) as the continuous control region. In the third combustion region A3 (combustion rate = 30%) to the fourth combustion region A4 (30% <combustion rate ≦ 60%), for example, the combustion amount is continuously increased in the range from the combustion rate 30% to the combustion rate 60%. Since it can be controlled to be able to be increased or decreased, it is possible to achieve an effect that it is excellent in terms of pressure stability.

The control unit 4 determines the step value control unit 42 (first combustion region A1, second combustion region A2) based on a preset reference value according to the magnitude of the detected steam pressure detected by the steam pressure detection unit 3. The combustion amount of the boiler 2 is controlled by the third combustion region A3, the fifth combustion region A5) or the continuous control unit 43 (fourth combustion region A4, sixth combustion region A6).
By doing so, the control part 4 can be controlled to burn in the combustion region of an appropriate material according to the magnitude of the detected steam pressure detected by the steam pressure detecting part 3.

<Setting reference value>
The setting reference value will be described with reference to FIG.
In order to prevent hunting (repetition of ON-OFF) of the combustion apparatus with respect to the set reference value for the above determination, the first value set in the step value control region when the steam pressure is in the increasing direction (the load amount is decreasing). A set reference value P′4 serving as a reference for shifting from the third combustion region A3 (combustion rate 30%) to the second combustion region A2 (combustion rate 20%) set in the step value control region; When the load amount is increasing), the second combustion region A2 (combustion rate 20%) set in the step value control region shifts to the third combustion region A3 (combustion rate 30%) set in the step value control region. A predetermined difference (differential) can be provided between the reference set reference value P4 and the reference value P4 so that P′4 is larger than P4. A set reference value P′5 serving as a reference for shifting from the second combustion region A2 (combustion rate 20%) set in the step value control region to the first combustion region A1 (combustion stop) set in the step value control region; The second combustion region A2 (burning rate 20) set in the step value control region from the first combustion region A1 (combustion stop) set in the step value control region when the steam pressure is in the descending direction (load amount increasing direction). Similarly, a predetermined difference (differential) can be provided so that P′5 is larger than P5 for the set reference value P5 serving as a reference for shifting to (%). It should be noted that the pressure zone can be further wrapped by providing a delay time for confirming the pressure change.

Further, with respect to the set reference value for the above determination, in order to ensure pressure stability, when the steam pressure is in the increasing direction (load amount decreasing direction), the fifth combustion region A5 ( The set reference value P′2 serving as a reference for shifting from the combustion rate 75%) to the fourth combustion region A4 (30% <combustion rate ≦ 60%) set in the continuous control region is set in the continuous control region. The target pressure value SV4 in the combustion region A4 can be set.
Further, when the steam pressure is in the increasing direction (the load amount is decreasing), the sixth combustion region A6 (75% <combustion rate ≦ 100%) set in the continuous control region is set in the step value control region. From the sixth combustion region A6 (75% <combustion rate ≦ 100%) set in the continuous control region, based on the set reference value P′1 serving as a reference for shifting to the fifth combustion region A5 (combustion rate 75%), It is possible to shift to the fifth combustion region A5 (combustion rate 75%) set in the step value control region. Moreover, it becomes a reference | standard which transfers to 3rd combustion area | region A3 (combustion rate 30%) set to the step value control area | region from 4th combustion area | region A4 (30% <combustion rate <= 60%) set to the continuous control area | region. Based on the set reference value P′3, the third combustion region A3 (combustion rate) set in the step value control region from the fourth combustion region A4 (30% <combustion rate ≦ 60%) set in the continuous control region. 30%).

Conversely, when the steam pressure is in the descending direction (in which the load is increasing), in order to ensure pressure stability, from the fifth combustion region A5 (combustion rate 75%) set in the step value control region. Set to the sixth combustion region A6 (75% <combustion rate ≦ 100%) set to the sixth combustion region A6 (75% <combustion rate ≦ 100) set in the continuous control region. %) At a target pressure value SV6. Similarly, a reference is made to shift from the third combustion region A3 (combustion rate 30%) set in the step value control region to the fourth combustion region A4 (30% <combustion rate ≦ 60%) set in the continuous control region. The set reference value P3 can be set to be the target pressure value SV4 in the fourth combustion region A4 (30% <combustion rate ≦ 60%) set in the continuous control region.
Further, when the steam pressure is in the downward direction (the load amount is increasing), the fourth combustion region A4 (30% <combustion rate ≦ 60%) set in the continuous control region is changed to the fifth value set in the step value control region. Based on the set reference value P2 serving as a reference for shifting to the combustion region A5 (combustion rate 75%), it is possible to shift to the fifth combustion region A5 set in the step value control region (combustion rate 75%).

  Next, the control of the control unit 4 will be specifically described with reference to FIG. 4 when the steam pressure decreases (when the load amount increases) and when the steam pressure increases (when the load amount decreases).

<When the steam pressure drops (load increases)>
First, the setting reference value and the control of the control unit 4 when the steam pressure decreases (when the load amount increases) will be described.

When the steam pressure is in the downward direction (the load amount is increasing), the setting reference value is set as follows as shown on the left side of FIG.
(1) A set reference value serving as a reference for shifting from the fifth combustion region A5 (combustion rate = 75%) to the sixth combustion region A6 (75% <combustion rate ≦ 100%) is P1,
(2) A set reference value serving as a reference for shifting from the fourth combustion region A4 (30% <combustion rate ≦ 60%) to the fifth combustion region A5 (combustion rate = 75%) is P2,
(3) A set reference value serving as a reference for shifting from the third combustion region A3 (combustion rate = 30%) to the fourth combustion region A4 (30% <combustion rate ≦ 60%) is P3,
(4) A set reference value serving as a reference for shifting from the second combustion region A2 (combustion rate = 20%) to the third combustion region A3 (combustion rate = 30%) is P4,
(5) P5 is a set reference value serving as a reference for shifting from the first combustion region A1 (combustion stop) to the second combustion region A2 (combustion rate = 20%).
And

  As shown on the left side of FIG. 4, the control unit 4 controls the step value control unit 42 (first combustion region A1, second combustion region A2, third combustion temperature) according to the detected steam pressure detected by the steam pressure detection unit 3. The combustion amount of the boiler 2 is controlled by the combustion region A3, the fifth combustion region A5) or the continuous control unit 43 (fourth combustion region A4, sixth combustion region A6).

<When steam pressure drops>
When the steam pressure is in the descending direction (load is increasing),
(1) When the steam pressure is P5 or higher, the control unit 4 controls the first combustion region A1 (combustion stop).
(2) When the steam pressure falls below P5, the control unit 4 shifts to control by the step value control unit 42 (second combustion region A2 (combustion rate = 20%)), and the steam pressure reaches P4 or more. In the meantime, control by the step value control unit 42 (second combustion region A2 (combustion rate = 20%)) is performed.
(3) When the steam pressure falls below P4, the control unit 4 shifts to control by the step value control unit 42 (third combustion region A3 (combustion rate = 30%)), and the steam pressure reaches P3 or more. In the meantime, control by the step value control unit 42 (third combustion region A3 (combustion rate = 30%)) is performed.
(4) When the steam pressure falls below P3, the control unit 4 shifts to the control by the continuous control unit 43 (fourth combustion region A4 (30% <combustion rate ≦ 60%)), and the steam pressure reaches P2 or more. In the meantime, control by the continuous control unit 43 (fourth combustion region A4 (30% <combustion rate ≦ 60%)) is performed.
Here, in order to ensure pressure stability, the third combustion region A3 (combustion rate = 30%) set in the step value control region to the fourth combustion region A4 set in the continuous control region (30% <combustion). The set reference value P3, which is a reference for shifting to the rate ≦ 60%)), becomes equal to the target pressure value SV4 in the fourth combustion region A4 (30% <combustion rate ≦ 60%)) set in the continuous control region. It is preferable to set.
(5) When the steam pressure falls below P2, the control unit 4 shifts to control by the step value control unit 42 (fifth combustion region A5 (combustion rate = 75%)), and the steam pressure is between P1 and higher. Then, the control by the step value control unit 42 (the fifth combustion region A5 (combustion rate = 75%)) is performed.
(6) When the steam pressure falls below P1, the control unit 4 shifts to control by the continuous control unit 43 (sixth combustion region A6 (75% <combustion rate ≦ 100%)).
Here, in order to ensure the pressure stability, the sixth combustion region A6 (75% << 5%) set in the continuous control region from the fifth combustion region A5 (combustion rate = 75%) set in the step value control region. The set reference value P1 serving as a reference for shifting to the combustion rate ≦ 100%)) is equal to the target pressure value SV6 in the sixth combustion region A6 (75% <combustion rate ≦ 100%) set in the continuous control region. It is preferable to set to.

<When steam pressure rises (load reduction)>
Next, the setting reference value and the control of the control unit 4 when the steam pressure increases (when the load amount decreases) will be described.

When the steam pressure is in the increasing direction (the load amount is decreasing), the setting reference value is set as follows, as shown on the right side of FIG.

(1) A set reference value serving as a reference for shifting from the sixth combustion region A6 (75% <combustion rate ≦ 100%) to the fifth combustion region A5 (combustion rate = 75%) is P′1,
(2) A set reference value serving as a reference for shifting from the fifth combustion region A5 (combustion rate = 75%) to the fourth combustion region A4 (30% <combustion rate ≦ 60%) is P′2,
(3) P′3 is a set reference value serving as a reference for shifting from the fourth combustion region A4 (30% <combustion rate ≦ 60%) to the third combustion region A3 (combustion rate = 30%),
(4) P′4 is a set reference value serving as a reference for shifting from the third combustion region A3 (combustion rate = 30%) to the second combustion region A2 (combustion rate = 20%).
(5) P′5 is a set reference value serving as a reference for shifting from the second combustion region A2 (combustion rate = 20%) to the first combustion region A1 (combustion stop).
And
Here, as described above, in order to prevent hunting (repetition of ON-OFF) of the combustion device,
P1 <P'1, P2 <P'2, P3 <P'3, P4 <P'4, P5 <P'5
Can be set to be

  As shown on the right side of FIG. 4, the controller 4 controls the step value controller 42 (the first combustion region A1, the second combustion chamber) when the detected steam pressure detected by the steam pressure detector 3 increases (load amount decreases). The combustion amount of the boiler 2 is controlled by the combustion region A2, the third combustion region A3, the fifth combustion region A5) or the continuous control unit 43 (fourth combustion region A4, sixth combustion region A6).

When the steam pressure rises (load reduction),
(1) When the steam pressure is P′1 or less, the control unit 4 performs control (sixth combustion region A6 (75% <combustion rate ≦ 100%)) by the continuous control unit 43.
(2) When the steam pressure exceeds P′1, the control unit 4 shifts to control by the step value control unit 42 (fifth combustion region A5 (combustion rate = 75%)), and the steam pressure reaches P′2 or less. In the meantime, control by the step value control unit 42 (fifth combustion region A5 (combustion rate = 75%)) is performed.
(3) When the steam pressure exceeds P′2, the control unit 4 shifts to control by the continuous control unit 43 (fourth combustion region A4 (30% <combustion rate ≦ 60%)), and the steam pressure is P′3. Control by the continuous control unit 43 (fourth combustion region A4 (30% <combustion rate ≦ 60%)) is performed until the following.
Here, in order to ensure pressure stability, the fourth combustion region A4 (30% <30% <5%) set from the fifth combustion region A5 (combustion rate = 75%) set in the step value control region to the continuous control region. The set reference value P′2 serving as a reference for shifting to the combustion rate ≦ 60% is equal to the target pressure value SV4 in the fourth combustion region A4 (30% <combustion rate ≦ 60%) set in the continuous control region. It is preferable to set to.
(4) When the steam pressure exceeds P′3, the control unit 4 shifts to the control by the step value control unit 42 (third combustion region A3 (combustion rate = 30%)) until the steam pressure reaches P′4 or less. In the meantime, the control by the step value control unit 42 (third combustion region A3 (combustion rate = 30%)) is performed.
(5) When the steam pressure exceeds P′4, the control unit 4 shifts to the control by the step value control unit 42 (second combustion region A2 (combustion rate = 20%)) until the steam pressure reaches P′5 or less. In the meantime, control by the step value control unit 42 (second combustion region A2 (combustion rate = 20%)) is performed.
(6) When the steam pressure exceeds P′5, the control unit 4 controls the first combustion region A1 (combustion stop).

  As described above, the control unit 4 determines the step value control unit 42 (first combustion region A1, second combustion region A2, third combustion) according to the magnitude of the detected steam pressure detected by the steam pressure detection unit 3. The combustion amount of the boiler 2 can be controlled by the region A3, the fifth combustion region A5) or the continuous control unit 43 (fourth combustion region A4, sixth combustion region A6).

As described above, in the case of the step value / continuous control setting, the control unit 4 can perform control so that the combustion is performed in the combustion region of the appropriate material in accordance with the magnitude of the detected steam pressure detected by the steam pressure detection unit 3. it can.
For example, if the fourth combustion region A4 (30% <combustion rate ≦ 60%) is set as the step value control region, the pressure fluctuation range is large because the control is performed with the combustion rate of 30% and the combustion rate of 60%. Although there is a problem in terms of pressure stability, as shown in FIG. 3B, by setting the fourth combustion region A4 (30% <combustion rate ≦ 60%) as the continuous control region, the third combustion region A3 (combustion) Rate = 30%) to 4th combustion zone A4 (30% <combustion rate ≤ 60%), the combustion amount can be controlled to be continuously increased or decreased within the range from 30% to 60%, pressure stability The effect that it is excellent in the point of property can be show | played.

  As described above, the case where the combustion region of the boiler device 1 is divided into the first combustion region A1 to the sixth combustion region A6 has been described, but when the combustion region is divided into arbitrary combustion regions, the set reference value and the target pressure value are similarly set. By providing the control unit 4, another pressure band is made continuous based on a preset reference value according to the magnitude of the detected steam pressure detected by the steam pressure detecting unit 3. Transition control to the combustion region can be performed.

<Step value control setting>
Next, a case where all of the combustion regions divided into a plurality of combustion regions are set as the step value control region (step value control setting) will be described with reference to FIGS. 3C and 5.

FIG. 3C is a diagram illustrating an example of the boiler device 1 in which all combustion regions of the combustion regions divided into a plurality (five) are set as the step value control region.
As shown in FIG. 3C, the combustion rates set in advance corresponding to the combustion regions and the combustion regions are set as follows.
In addition, about the combustion rate 0% (combustion stop), it named the 1st combustion area | region A1 for convenience.
(1) 1st combustion area A1 (combustion rate 0%) That is, it sets to a combustion stop.
(2) In the second combustion region A2 (0% <combustion rate ≦ 20%), the combustion rate is set to 20%.
(3) In the third combustion region A3 (20% <combustion rate ≦ 30%), the combustion rate is set to 30%.
(4) In the fourth combustion region A4 (30% <combustion rate ≦ 60%), the combustion rate is set to 60%.
(5) In the fifth combustion region A5 (60% <combustion rate ≦ 75%), the combustion rate is set to 75%.
(6) In the sixth combustion region A6 (75% <combustion rate ≦ 100%), the combustion rate is set to 100%.

Then, so-called 6-position control is set that allows control in six combustion states (combustion position, combustion rate) when the combustion rate is 0% (combustion stop).
The N position control represents that the combustion amount of the step value control boiler can be controlled step by step to the N position including the combustion stop state.
In the embodiment, 6-position control is used. However, N may be an arbitrary integer, for example, 5-position control, 4-position control, 3-position control, or the like.

  Here, assuming that n is an integer satisfying “1 ≦ n ≦ 6”, the combustion rate set in the “nth combustion region” is hereinafter referred to as “nth combustion position”. This combustion state is sometimes referred to as the “nth combustion state”.

  By setting in this way, the stage value control unit 42 includes six stages including the first combustion state in which the combustion state of the boiler 2 is stopped in accordance with the steam pressure detected by the steam pressure detection unit 3. To control.

  The control unit 4 determines the step value control unit 42 (first combustion region A1 to sixth combustion region A6) based on a preset reference value according to the magnitude of the detected steam pressure detected by the steam pressure detection unit 3. ) To control the combustion amount of the boiler 2.

<Setting reference value>
The setting reference value will be described with reference to FIG.
Here, when n is an integer satisfying 2 ≦ n ≦ 6, the steam pressure increases in order to prevent hunting (repetition of ON-OFF) of the combustion apparatus with respect to the set reference value for the above determination ( Set reference value serving as a reference for shifting from the nth combustion region An set in the step value control region to the (n-1) th combustion region An-1 set in the step value control region when the load amount is in the decreasing direction) P (7-n) 2 is set to the step value control region from the (n-1) th combustion region An-1 set in the step value control region when the steam pressure is in the descending direction (load increase direction). In addition, the former P (7-n) 2 is larger than the latter P (7-n) 1 between the reference value P (7-n) 1 serving as a reference for shifting to the nth combustion region An. A predetermined difference (differential) can be provided. It should be noted that the pressure zone can be further wrapped by providing a delay time for confirming the pressure change.

  Next, when the steam pressure is lowered (when the load amount is increased) and when the steam pressure is increased (when the load amount is decreased), a description will be given with reference to FIG.

<When the steam pressure drops (load increases)>
First, the setting reference value and the control of the control unit 4 when the steam pressure decreases (when the load amount increases) will be described.

When the steam pressure is in the downward direction (the load amount is increasing), the setting reference value is set as follows as shown on the left side of FIG.
(1) A set reference value serving as a reference for shifting from the fifth combustion region A5 (combustion rate = 75%) to the sixth combustion region A6 (combustion rate = 100%) is P11,
(2) A set reference value serving as a reference for shifting from the fourth combustion region A4 (combustion rate = 60%) to the fifth combustion region A5 (combustion rate = 75%) is P21,
(3) P31 is a set reference value serving as a reference for shifting from the third combustion region A3 (combustion rate = 30%) to the fourth combustion region A4 (combustion rate = 60%).
(4) P41 is a set reference value serving as a reference for shifting from the second combustion region A2 (combustion rate = 20%) to the third combustion region A3 (combustion rate = 30%).
(5) P51 is a set reference value serving as a reference for shifting from the first combustion region A1 (combustion stop) to the second combustion region A2 (combustion rate = 20%).
And

  As shown on the left side of FIG. 5, the controller 4 controls the boiler according to the detected steam pressure detected by the steam pressure detector 3 by the step value controller 42 (first combustion region A1 to sixth combustion region A6). 2 is controlled.

<When steam pressure drops>
When the steam pressure is in the descending direction (load is increasing),
(1) When the steam pressure is P51 or higher, the control unit 4 controls the first combustion region A1 (combustion stop).
(2) When the steam pressure falls below P51, the control unit 4 shifts to the control by the step value control unit 42 (second combustion region A2 (combustion rate = 20%)), and the steam pressure is between P41 and higher. Then, control (second combustion region A2 (combustion rate = 30%)) by the step value control unit 42 is performed.
(3) When the steam pressure falls below P41, the control unit 4 shifts to the control by the step value control unit 42 (third combustion region A3 (combustion rate = 30%)), and the steam pressure is between P31 and above. Then, control by the step value control unit 42 (third combustion region A3 (combustion rate = 30%)) is performed.
(4) When the steam pressure falls below P31, the control unit 4 shifts to the control by the step value control unit 42 (fourth combustion region A4 (combustion rate = 60%)), and the steam pressure is between P21 and higher. Then, control by the step value control unit 42 (fourth combustion region A4 (combustion rate = 60%)) is performed.
(5) When the steam pressure falls below P21, the control unit 4 shifts to control by the step value control unit 42 (fifth combustion region A5 (combustion rate = 75%)), and the steam pressure is between P11 and above. Then, the control by the step value control unit 42 (the fifth combustion region A5 (combustion rate = 75%)) is performed.
(6) The control unit 4 performs control (sixth combustion region A6 (combustion rate = 100%)) by the step value control unit 42 when the steam pressure falls below P11.

<When steam pressure rises (load reduction)>
Next, the setting reference value and the control of the control unit 4 when the steam pressure increases (when the load amount decreases) will be described.

When the steam pressure is in the increasing direction (the load amount is decreasing), the setting reference value is set as follows, as shown on the right side of FIG.

(1) A set reference value serving as a reference for shifting from the sixth combustion region A6 (combustion rate = 100%) to the fifth combustion region A5 (combustion rate = 75%) is P12,
(2) A set reference value serving as a reference for shifting from the fifth combustion region A5 (combustion rate = 75%) to the fourth combustion region A4 (combustion rate = 60%) is P22.
(3) P32 is a set reference value serving as a reference for shifting from the fourth combustion region A4 (combustion rate = 60%) to the third combustion region A3 (combustion rate = 30%).
(4) A set reference value serving as a reference for shifting from the third combustion region A3 (combustion rate = 30%) to the second combustion region A2 (combustion rate = 20%) is P42,
(5) A set reference value serving as a reference for shifting from the second combustion region A2 (combustion rate = 20%) to the first combustion region A1 (combustion stop) is P52,
And
Here, as described above, in order to prevent hunting (repetition of ON-OFF) of the combustion device,
P11 <P12, P21 <P22, P31 <P32,
P41 <P42, P51 <P52
Can be set to be

  When the detected steam pressure detected by the steam pressure detecting unit 3 is in the increasing direction (the load amount is decreasing), the control unit 4 performs the step value control unit 42 (first combustion region A1) as shown on the right side of FIG. The combustion amount of the boiler 2 is controlled by the sixth combustion region A6).

When the steam pressure rises (load reduction),
(1) When the steam pressure is equal to or lower than P12, the control unit 4 performs control (sixth combustion region A6 (combustion rate = 100%)) by the step value control unit 42.
(2) When the steam pressure exceeds P12, the control unit 4 shifts to control by the step value control unit 42 (fifth combustion region A5 (combustion rate = 75%)), and the step is performed until the steam pressure is P22 or less. Control by the value control unit 42 (fifth combustion region A5 (combustion rate = 75%)) is performed.
(3) When the steam pressure exceeds P22, the control unit 4 shifts to control by the step value control unit 42 (fourth combustion region A4 (combustion rate = 60%)), and the step is performed until the steam pressure is equal to or lower than P32. Control by the value control unit 42 (fourth combustion region A4 (combustion rate = 60%)) is performed.
(4) When the steam pressure exceeds P32, the control unit 4 shifts to the control by the step value control unit 42 (third combustion region A3 (combustion rate = 30%)), and the step is performed until the steam pressure reaches P42 or less. Control by the value controller 42 (third combustion region A3 (combustion rate = 30%)) is performed.
(5) When the steam pressure exceeds P42, the control unit 4 shifts to the control by the step value control unit 42 (second combustion region A2 (combustion rate = 20%)). Control by the value control unit 42 (second combustion region A2 (combustion rate = 20%)) is performed.
(6) The control unit 4 performs control so that the first combustion region A1 (combustion stop) is reached when the steam pressure exceeds P52.

  As described above, the control unit 4 uses the stage value control unit 42 (the first combustion region A1 to the sixth combustion region A6) according to the magnitude of the detected steam pressure detected by the steam pressure detection unit 3 to the boiler 2. The amount of combustion can be controlled.

  As described above, the case where the combustion region of the boiler device 1 is divided into the first combustion region A1 to the sixth combustion region A6 has been described, but even when the combustion region is divided into arbitrary combustion regions, the setting reference value is similarly provided, The control unit 4 can perform control by the step value control unit 42 based on a predetermined set reference value according to the magnitude of the detected steam pressure detected by the steam pressure detection unit 3.

(Continuous control setting)
Finally, the case where all the combustion regions of the plurality of combustion regions are set to the continuous control region in which the combustion amount is continuously changed (continuous control setting) will be described.
FIG. 3D is a diagram illustrating an embodiment of the boiler device 1 in which all combustion regions of the combustion regions divided into a plurality (five) are set as continuous control regions.
Therefore, as shown in FIG. 3D, the combustion rate is continuously maintained in the range from the combustion stop state S0 and the minimum combustion state S1 (combustion state with 20% combustion rate) to the maximum combustion state S2 (combustion state with 100% combustion rate). Is set to be controllable automatically.

  In this case, the continuous control unit 43 sets the boiler 2 in the minimum combustion state S1 (so that the vapor pressure in the can detected by the vapor pressure detection unit 3 becomes a target pressure set in advance corresponding to the combustion region. Combustion is continuously performed within a range from a combustion state with a combustion rate of 20% to a maximum combustion state S2 (a combustion state with a combustion rate of 20%).

  In addition, when all the combustion areas of the divided combustion areas are set to a continuous control area in which the combustion amount is continuously changed, the control is the same as the control of the normal proportional control boiler, and the description is omitted. .

According to the boiler device 1 of the present embodiment, for example, the following effects are exhibited.
The boiler apparatus 1 according to the present embodiment corresponds to a boiler 1 having a combustion region divided into a plurality of parts, a steam pressure detection unit 3 that detects a steam pressure in the boiler 1, and a steam pressure detected by the steam pressure detection unit 3. And a control unit 4 for controlling the combustion state of the boiler 1, and the control unit 4 continuously sets a plurality of combustion regions, a step value control region for changing the combustion amount stepwise, or a combustion amount continuously. A setting unit 41 that sets the continuous control region to be changed, and a stage value control unit 42 that burns the boiler 2 at a preset combustion rate corresponding to the combustion region in the combustion region set in the step value control region. And in the combustion region set in the continuous control region, the continuous control for burning the boiler 2 so that the steam pressure detected by the steam pressure detection unit 3 becomes a preset target pressure corresponding to the combustion region. Part 4 And, equipped with a.

  Therefore, according to the present embodiment, for example, step value control is applied to a combustion region in which priority is given to responsiveness, and continuous control is applied to another predetermined combustion region in which priority is given to pressure stability. By applying it, it becomes possible to use the stability of continuous control and the responsiveness of step value control at the right place in one boiler device.

  Moreover, according to this embodiment, it can provide also as a boiler which can be switched to a proportional control boiler or a step value control boiler. By doing so, when a boiler is added to a unit control system composed of a plurality of step value control boilers or a unit control system composed of a plurality of proportional control boilers, the same boiler is appropriately switched to a proportional control boiler or a step value control boiler. Therefore, it can be added to any of the unit control systems including the step value control boiler or the proportional control boiler, and the model integration becomes easy.

As mentioned above, although preferred embodiment was described, this invention is not limited to embodiment mentioned above, It can implement with a various form.
For example, in the present embodiment, the storage unit 44 may include a reference table that stores predetermined setting reference values.

  For example, in the present embodiment, it has been described that the minimum combustion state of the boiler 2 is a combustion rate of 20% and the boiler 2 can perform continuous combustion at a combustion rate of 20% to 100%, but is not limited thereto. The combustion rate in the minimum combustion state may be arbitrarily set, for example, 10% or 0%.

For example, in this embodiment (step value / continuous control setting), the continuous control unit 43 has a combustion rate in the range from 30% to 60% in the fourth combustion region A4 (30% <combustion rate ≦ 60%). In the sixth combustion region A6 (75% <combustion rate ≦ 100%), the combustion amount is controlled so as to be continuously increased or decreased within the range of 75% to 100%. However, the present invention is not limited to this. For example, in the fourth combustion region A4 (30% <combustion rate ≦ 60%), the continuous control unit 43 sets the third combustion region A3 and the fifth combustion region so that the combustion rate ranges from 25% to 65%. The combustion rate in A5 may partially overlap.
Similarly, for example, in the sixth combustion region A4 (75% <combustion rate ≦ 100%), the combustion rate partially overlaps with the combustion rate in the fifth combustion region A5 as in the range from 70% to 100%. May be.

For example, in this embodiment, although divided into five combustion regions, it is not limited to five divisions. The number of divisions can be set as appropriate.
Moreover, although 20%, 30%, 60%, and 75% are exemplified as the combustion rate as the boundary value of the divided region, the combustion rate is not limited to such a combustion rate. For example, it may be 20% or 60%.

DESCRIPTION OF SYMBOLS 1 Boiler apparatus 2 Boiler 3 Steam pressure detection part 4 Control part 41 Setting part 42 Step value control part 43 Continuous control part 44 Memory | storage part A1 1st combustion area A2 2nd combustion area A3 3rd combustion area A4 4th combustion area A5 1st 5 combustion area A6 6th combustion area

Claims (5)

A boiler having a combustion region divided into a plurality of parts;
A steam pressure detector for detecting the steam pressure in the boiler;
A controller that controls the combustion state of the boiler according to the steam pressure detected by the steam pressure detector,
The control unit is configured to set each of the plurality of combustion regions to a step value control region that changes the combustion amount stepwise, or a continuous control region that continuously changes the combustion amount;
In the combustion region set in the step value control region, a step value control unit for burning the boiler at a preset combustion rate corresponding to the combustion region;
In the combustion region set in the continuous control region, the continuous control unit combusts the boiler so that the steam pressure detected by the steam pressure detection unit becomes a preset target pressure set in advance corresponding to the combustion region. A boiler device comprising:   The boiler device according to claim 1, wherein the control is switched from the control by the continuous control unit to the control by the step value control unit according to a predetermined change in the steam pressure detected by the steam pressure detection unit.   The boiler device according to claim 1 or 2, wherein the control is switched from the control by the step value control unit to the control by the continuous control unit according to a predetermined change in the steam pressure detected by the steam pressure detection unit.   The boiler device according to claim 1, wherein the setting unit sets all the plurality of combustion regions as step value control regions, thereby setting the boiler as a step value control boiler.   The boiler device according to claim 1, wherein the boiler is set as a proportional control boiler by setting all the plurality of combustion regions to a continuous control region by the setting unit.

Images