Control device, control method, incinerator equipment and prediction model generation device

Abstract

The present invention controls to reduce the influence of process values. The control device (3) includes: a prediction unit (31) that predicts the predicted value of the control amount at the control time point based on multiple process values ​​in the incinerator equipment (100) that affect the control amount; and a control unit (32) that calculates an input value indicating the size of the input provided to the control object for controlling the control amount based on the predicted value, and controls the control amount based on the input value.

Description

Technical Field

[0001] The present invention relates to a control device for controlling a control variable in an incinerator device. Background Art

[0002] In waste treatment facilities, exhaust gas generated by burning waste in an incinerator is used to generate steam in a boiler, the generated steam is superheated by a superheater and desuperheated by a desuperheater, and the steam is supplied to a steam turbine power generation device, etc. In such waste treatment facilities, in order to provide a stable steam supply, control variables such as steam temperature are controlled to a specified value.

[0003] For example, Patent Document 1 describes that feedforward control based on the boiler heat input amount is performed together with proportional integral derivative (PID) control of the feedback of the main steam temperature.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2007-187340 Summary of the invention

[0007] Problems to be solved by the invention

[0008] However, the control quantity such as steam temperature is affected by various process values ​​in the boiler, superheater, incinerator, etc. Therefore, as described in Patent Document 1, only feedforward control using the boiler heat input and the main steam temperature at the outlet of the two superheaters cannot reduce the influence of the process value, and the control is insufficient.

[0009] An object of one aspect of the present invention is to perform control so as to mitigate the influence of a process value.

[0010] Means used to solve problems

[0011] In order to solve the above-mentioned problem, a control device in one form of the present invention is a control device for controlling a control quantity in an incinerator equipment, wherein the incinerator equipment includes: an incinerator; a boiler that uses exhaust gas from the incinerator to generate steam; a superheater that superheats the steam generated by the boiler; and a desuperheater that reduces the temperature of the steam superheated by the superheater, wherein the control device includes: a prediction unit that predicts a predicted value of the control quantity at a control time point based on a plurality of process values ​​in the incinerator equipment that affect the control quantity; and a control unit that calculates an input value indicating the size of an input provided to the control object for controlling the control quantity based on the predicted value, and controls the control quantity based on the input value.

[0012] Effects of the Invention

[0013] According to one aspect of the present invention, control can be performed to mitigate the influence of the process value. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] [ Figure 1 ] is a diagram showing the structure of an incinerator equipment according to one embodiment of the present invention.

[0015] [ Figure 2 ] is a flowchart showing the order of processing of controlling the control quantity by the control device in the incinerator equipment.

[0016] [ Figure 3 ] is a graph showing a comparison between a current value of a control amount and a predicted value of the control amount after one minute based on predictive control by the control device.

[0017] [ Figure 4 ] is a graph showing a comparison between the current value of the control amount and the predicted value of the control amount two minutes later based on the predictive control of the control device.

[0018] [ Figure 5 ] is a graph showing a comparison between the current value of the control amount and the predicted value of the control amount three minutes later based on the predictive control of the control device. DETAILED DESCRIPTION

[0019] 〔Incinerator equipment〕

[0020] First, incinerator facilities common to the embodiments of the present invention will be described in detail.

[0021] <Overview of incinerator facilities>

[0022] Figure 1 It is a figure which shows the structure of the incinerator facility 100 which concerns on one Embodiment of this invention.

[0023] like Figure 1 As shown, the incinerator equipment 100 includes: an incinerator 1 , a steam generating device 2 and a control device 3 .

[0024] The incinerator 1 is a stoker-type incinerator that burns waste while conveying it. In a combustion chamber formed inside the incinerator 1, the waste is burned and combustion gas generated by the waste, which is mainly composed of carbon and hydrogen, is burned. As a result of the combustion, the exhaust gas discharged from the combustion chamber is subjected to a predetermined exhaust treatment in the exhaust path 1a and introduced into the steam generator 2.

[0025] The steam generating device 2 generates steam by means of a boiler 21 using exhaust gas as a heat source. The steam generating device 2 superheats the steam by means of a superheating unit 23 and reduces the temperature of the superheated steam by means of a desuperheating unit 24, thereby generating outlet steam of an appropriate temperature. The outlet steam is used for power generation, heating, and the like.

[0026] The control device 3 is a device for controlling the controlled amount of the controlled object in the incinerator equipment 100. The control device 3 predicts the predicted value of the controlled amount at the control time point based on a plurality of process values ​​in the incinerator equipment 100 that affect the controlled amount, and controls the controlled amount based on the predicted value. In addition, the control device 3 performs feedback control so that the controlled amount becomes the target value. The control device 3 switches and performs predicted value control and feedback control based on the predicted value as needed.

[0027] is described in.

[0028] <Incinerator Details>

[0029] The incinerator 1 includes a hopper 11, a waste material supply device 12, a grate portion 13, an air supply device 14, an air preheater 15, an air supply pipe 16, a thermometer 17, a thermometer 18, and baffles 19a to 19c.

[0030] The hopper 11 is an inlet for waste to be put in by a crane, etc. The waste supply device 12 supplies the waste put in from the hopper 11 to the grate 13. The speed of waste supply by the waste supply device 12 can be controlled to adjust the incineration amount of the waste.

[0031] The grate unit 13 conveys the waste in a state where the waste is loaded, and dries and burns the waste. The grate unit 13 includes a drying grate 131 (grate), a combustion grate 132 (grate), and a post-combustion grate 133 (grate).

[0032] The drying grate 131 is a grate for drying the waste supplied from the waste supply device 12, and is arranged at the highest position. The combustion grate 132 is provided at a position lower than the drying grate 131 in the front section of the combustion grate 132, and is a grate for burning the dried waste. The post-combustion grate 133 is provided at a position lower than the combustion grate 132 in the front section of the post-combustion grate 133, and is a grate for completely burning the incompletely burned waste. Air for drying and burning is supplied from below to the drying grate 131, the combustion grate 132, and the post-combustion grate 133, respectively.

[0033] The air supply device 14 is a device that supplies air for generating combustion air to be supplied to the grate portion 13 to the air preheater 15. The air supply device 14 includes a blower and the like.

[0034] The air preheater 15 is a device that heats and discharges the air supplied from the air supply device 14. The air supply pipe 16 branches to supply the heated air discharged from the air preheater 15 to the drying grate 131, the combustion grate 132, and the post-combustion grate 133, respectively.

[0035] The thermometer 17 measures the temperature of the air flowing through the air supply pipe 16. The thermometer 17 is arranged upstream of the branching portion of the air supply pipe 16. The thermometer 18 measures the temperature of the drying grate 131, the combustion grate 132, and the post-combustion grate 133 of the grate section 13. Figure 1 Although it is representatively depicted as being arranged at one location, it is individually arranged above each of the drying grate 131, the combustion grate 132, and the post-combustion grate 133. The temperatures of the combustion air supplied to the drying grate 131, the combustion grate 132, and the post-combustion grate 133 are controlled by the control device 3 based on the measured temperatures of the thermometers 17 and 18.

[0036] The damper 19a is provided at the branch portion of the air supply pipe 16 for supplying air to the drying grate 131, and adjusts the flow rate of air supplied to the drying grate 131. The damper 19b is provided at the branch portion of the air supply pipe 16 for supplying air to the combustion grate 132, and adjusts the flow rate of air supplied to the combustion grate 132. The damper 19c is provided at the branch portion of the air supply pipe 16 for supplying air to the post-combustion grate 133, and adjusts the flow rate of air supplied to the post-combustion grate 133.

[0037] <Details of the steam generating device>

[0038] The steam generation device 2 includes a boiler 21 , a water supply valve 22 , a superheating unit 23 , a temperature reducing unit 24 , a water injection unit 25 , a temperature measurement system 26 , a flow rate measurement system 27 , a pressure gauge 28 , and an oxygen concentration meter 29 .

[0039] The boiler 21 is a steam generator that generates steam using exhaust gas from the incinerator 1. The boiler 21 generates saturated steam by heating water stored inside using the exhaust gas. The water supply valve 22 is a valve that adjusts the amount of water supplied to the boiler 21.

[0040] The superheater 23 superheats the steam generated by the boiler 21 by the heat of the exhaust gas. The superheater 23 includes a primary superheater 231 (superheater), a secondary superheater 232 (superheater), and a tertiary superheater 233 (superheater). The primary superheater 231 superheats the steam from the boiler 21. The secondary superheater 232 heats the steam that has passed through the primary superheater 231. The tertiary superheater 233 heats the steam that has passed through the secondary superheater 232.

[0041] The exhaust gas from the incinerator 1 is supplied to the primary superheater 231, the secondary superheater 232, and the tertiary superheater 233 via an exhaust gas supply pipe not shown. The exhaust gas is supplied to the tertiary superheater 233 at a position closest to the exhaust gas outlet of the incinerator 1. The exhaust gas is supplied to the secondary superheater 232 at a position closest to the exhaust gas outlet after the tertiary superheater 233. The exhaust gas is supplied to the primary superheater 231 at a position farthest from the exhaust gas outlet. As a result, the temperature of the exhaust gas supplied to the superheater 23 is the highest in the tertiary superheater 233, the second highest in the secondary superheater 232, and the lowest in the primary superheater 231.

[0042] The temperature reduction unit 24 reduces the temperature of the steam superheated by the primary superheater 231 and the secondary superheater 232. The temperature reduction unit 24 includes a primary desuperheater 241 and a secondary desuperheater 242. The primary desuperheater 241 reduces the temperature of the steam superheated by the primary superheater 231 by the water injected therein. The secondary desuperheater 242 reduces the temperature of the steam superheated by the secondary superheater 232 by the water injected therein.

[0043] The water injection unit 25 injects water into the primary desuperheater 241 and the secondary desuperheater 242 of the cooling unit 24, respectively. The water injection unit 25 has a primary water injection valve 251 (water injection valve) and a secondary water injection valve 252 (water injection valve). The primary water injection valve 251 is a water injection valve that adjusts the injection amount of cooling water into the primary desuperheater 241 by spraying water. The secondary water injection valve 252 is a water injection valve that adjusts the injection amount of cooling water into the secondary desuperheater 242 by spraying water. The primary water injection valve 251 and the secondary water injection valve 252 are control valves whose openings are controlled by the control device 3.

[0044] The temperature measurement system 26 measures the temperature of various locations in the steam generation device 2. The temperature measurement system 26 includes a plurality of thermometers 261 to 268. The thermometer 261 measures the temperature of water supplied by the water supply valve 22. The thermometer 262 measures the temperature of the exhaust gas supplied to the vicinity of the outlet of the boiler 21. The thermometer 263 measures the temperature of the main steam, which is the steam discharged from the boiler 21. The thermometer 264 measures the temperature of the steam at the outlet of the primary superheater 231. The thermometer 265 measures the temperature of the steam at the outlet of the primary desuperheater 241, that is, the inlet of the secondary superheater 232. The thermometer 266 measures the temperature of the steam at the outlet of the secondary superheater 232. The thermometer 267 measures the temperature of the steam at the outlet of the secondary desuperheater 242, that is, the inlet of the tertiary superheater 233. The thermometer 268 measures the temperature of the steam (exit steam) at the outlet of the tertiary superheater 233, that is, the outlet of the steam generation device 2.

[0045] The flow measurement system 27 measures the flow rate of the fluid flowing in the steam generation device 2. The flow measurement system 27 includes a flow meter 271 and a flow meter 272. The flow meter 271 measures the flow rate of water supplied by the water supply valve 22. The flow meter 272 measures the flow rate of the exhaust gas flowing near the discharge portion 1b of the incinerator 1.

[0046] The pressure gauge 28 measures the pressure of the outlet steam. The oxygen concentration meter 29 measures the oxygen concentration of the exhaust gas flowing near the discharge portion 1b.

[0047] <Details of control device>

[0048] The control device 3 includes a prediction unit 31, a control unit 32, and a switching unit 33. In the example described below, the control object is set to the secondary water injection valve 252, and the control amount is set to the temperature (outlet steam) of the outlet steam of the tertiary superheater 233. In addition, the switching unit 33 is a switch-like switch that switches the connection between the first control unit 321 and the control object (secondary water injection valve 252) and the connection between the second control unit 322 and the control object.

[0049] In the incinerator equipment 100, the prediction unit 31 predicts the predicted value of the control amount at the control time point based on a plurality of process values ​​that affect the control amount of the control object. The prediction unit 31 performs the prediction based on the prediction model generated by the prediction model generation device 4. As the prediction model, for example, a model generated by multiple regression analysis is used, and the multiple regression analysis uses the control amount as the target variable and the plurality of process values ​​as the explanatory variables.

[0050] The prediction unit 31 can be configured as follows (1) to (4).

[0051] (1) The prediction unit 31 predicts the amount of change in the controlled variable from the present time to the first predetermined time later as a predicted value.

[0052] (2) The prediction unit 31 predicts the controlled variable based on a prediction model, wherein the prediction model sets the difference between the value of the controlled variable after a first predetermined time from the current time and the current value of the controlled variable as a target variable and sets the process value as an explanatory variable. In this case, the first predetermined time is a delay time based on a delay element of the control.

[0053] (3) The explanatory variable is the difference between the current value of the process value and the value of the process value a second predetermined time ago from the current value.

[0054] (4) The target variable is the difference between the value of the steam temperature after the first predetermined time from the present and the present value of the steam temperature. The controlled variable in this case is the temperature of the outlet steam.

[0055] The control unit 32 includes a first control unit 321 , a second control unit 322 , and a switching control unit 323 in order to control the control amount.

[0056] The first control unit 321 calculates the input value indicating the size of the input to be provided to the control object in order to control the control amount based on the predicted value, and controls the control amount based on the input value. Specifically, the first control unit 321 controls the water injection amount of the secondary water injection valve 252 using the opening (%) of the secondary water injection valve 252 as an input value, thereby controlling the outlet steam temperature of the tertiary superheater 233 as the control amount. Therefore, the prediction unit 31, the first control unit 321, the switching unit 33 and the secondary water injection valve 252 constitute a predictive control system PCS that controls the control amount based on the predicted value. If the control object and the control amount are different, the structure of the predictive control system PCS will of course be different accordingly.

[0057] The second control unit 322 performs feedback control to control the control amount so that the control amount is consistent with the target value. Specifically, the second control unit 322 controls the opening of the secondary water injection valve 252 so that the deviation of the control amount (outlet steam temperature) from the target value is 0. Therefore, the second control unit 322, the switching unit 33, the secondary water injection valve 252 and the thermometer 268 constitute a feedback control system FBCS that controls the control amount through feedback control. If the control object and the control amount are different, the structure of the feedback control system FBCS will of course be different accordingly.

[0058] When the control unit 32 performs control using the prediction control system PCS based on the first control unit 321, when the deviation of the current value of the controlled amount from the prediction value exceeds a predetermined value, the switching control unit 323 controls the switching action of the switching unit 33 so as to switch to the feedback control system FBCS. In addition, when the control unit 32 performs control using the feedback control system FBCS, when the deviation is monitored and becomes less than the predetermined value, the switching control unit 323 controls the switching action of the switching unit 33 so as to switch to the prediction control system PCS.

[0059] <Prediction model generation device>

[0060] The prediction model generation device 4 is a device that generates a prediction model for the prediction unit 31 of the control device 3 to predict the prediction value, and includes a computer. The prediction model generation device 4 uses the measured process value as input data and the measured control amount as output data to perform machine learning, thereby generating a prediction model. The prediction model generation device 4 includes a weight determination unit 41 to generate the prediction model.

[0061] The weight determination unit 41 determines the weight of the prediction model that minimizes the deviation of the predicted value predicted using the input data relative to the output data. For example, when the regression equation of multiple regression analysis is used as the prediction model, the weight is equivalent to the regression coefficient in the regression equation. In addition, the weight determination unit 41 also determines the intercept and weight in the regression equation. By including such a weight determination unit 41, the prediction model generation device 4 can generate a prediction model with high prediction accuracy.

[0062] The weight determination unit 41 may determine the weight using other machine learning methods, such as deep learning. Other machine learning methods that can be applied include extreme learning machines (ELM) and support vector regression (SVR).

[0063] In addition, the prediction model generation device 4 includes a time setting unit 42. The time setting unit 42 sets the second predetermined time for each process value through a parameter study so that the accuracy of the prediction model becomes the highest. The explanatory variable is the difference between the current value of the process value and the value of the process value before the second predetermined time from the current time.

[0064] When the prediction model generation device 4 generates a prediction model of multiple regression analysis as follows, for example, the time setting unit 42 determines the width of the same difference, that is, the second predetermined time, for the explanatory variable X1, the explanatory variable X2, and the explanatory variable X3 in the following order A to order D. Here, "now" indicates the current value, and "before" indicates the value before the current value.

[0065] Y=a0

[0066] +a1*(X1_now-X1_before)

[0067] +a2*(X2_now-X2_before)

[0068] +a3*(X3_now-X3_before)

[0069] (Sequence A) The width of the difference that improves the accuracy is determined by using the same width of the difference for the explanatory variable X1, the explanatory variable X2, and the explanatory variable X3.

[0070] (Case A1)

[0071] X1: 1min, X2: 1min, X3: 1min

[0072] (Case A2)

[0073] X1: 2min, X2: 2min, X3: 2min

[0074] (Case A3)

[0075] X1: 3min, X2: 3min, X3: 3min

[0076] Here, case A2 is assumed to be the best.

[0077] (Sequence B) The widths of the differences of the explanatory variable X2 and the explanatory variable X3 are fixed at the widths determined in sequence A, and the width of the difference of the explanatory variable X1 is examined.

[0078] (Case B1)

[0079] X1: 1min, X2: 2min, X3: 2min

[0080] (Case B2)

[0081] X1: 2min, X2: 2min, X3: 2min

[0082] (Case B3)

[0083] X1: 3min, X2: 2min, X3: 2min

[0084] Here, case B1 is assumed to be the best.

[0085] (Sequence C) The width of the difference of the explanatory variable X1 is fixed at the width determined in sequence B, the width of the difference of the explanatory variable X3 is fixed at the width determined in sequence A, and the width of the difference of the explanatory variable X2 is studied.

[0086] (Case C1)

[0087] X1: 1min, X2: 1min, X3: 2min

[0088] (Case C2)

[0089] X1: 1min, X2: 2min, X3: 2min

[0090] (Case C3)

[0091] X1: 1min, X2: 3min, X3: 2min

[0092] Here, case C3 is assumed to be the best.

[0093] (Sequence D) The width of the difference of the explanatory variable X1 is fixed at the width determined in sequence B, the width of the difference of the explanatory variable X2 is fixed at the width determined in sequence C, and the width of the difference of the explanatory variable X3 is studied.

[0094] (Case D1)

[0095] X1: 1min, X2: 3min, X3: 1min

[0096] (Case D2)

[0097] X1: 1min, X2: 3min, X3: 2min

[0098] (Case D3)

[0099] X1: 1min, X2: 3min, X3: 3min

[0100] Here, case D2 is assumed to be the best.

[0101] From the above, case D2 is the most accurate prediction. When the number of explanatory variables increases, the same operations as sequence B to sequence D are repeated.

[0102] Since the prediction model generation device 4 includes the time setting unit 42, the prediction accuracy of the prediction unit using the prediction model can be improved.

[0103] <Overview of control operation>

[0104] An outline of the operation (control method) based on the control amount of the control device 3 will be described. Figure 2 It is a flowchart showing the procedure of a process of controlling a controlled variable by the control device 3 .

[0105] like Figure 2 As shown, after the control device 3 is started, the prediction control system PCS is set (step S1). The prediction control system PCS is set by the switching control unit 323 of the control device 3 controlling the switching unit 33 so that the switching unit 33 switches to the connection with the first control unit 321.

[0106] Next, the prediction unit 31 acquires process values ​​from various locations in the incinerator facility 100 (step S2). The prediction unit 31 uses the prediction model generated by the prediction model generation device 4 to predict the prediction value based on the acquired process values ​​(step S3, prediction step).

[0107] The first control unit 321 of the control unit 32 calculates the input value provided to the control object based on the predicted value predicted by the prediction unit 31 (step S4, control process). The first control unit 321 provides the calculated input value to the control object, and controls the control amount based on the input value (step S5, control process).

[0108] The switching control unit 323 monitors the deviation (absolute value) of the current value of the controlled variable relative to the predicted value to determine whether the deviation exceeds the prescribed value (step S6). In step S6, if the switching control unit 323 determines that the deviation exceeds the prescribed value (yes), the switching unit 33 switches from the predictive control system PCS to the feedback control system FBCS (step S7). In the switching, the switching unit 33 switches the connection with the controlled object from the first control unit 321 to the second control unit 322 under the control of the switching control unit 323. Then, the second control unit 322 controls the controlled variable through the feedback control system FBCS (step S8), and the process returns to step S6.

[0109] In this way, when the control amount changes too much under the control by the predictive control system PCS and the deviation exceeds the predetermined value, the control is switched to the control by the feedback control system FBCS. Thus, the control amount can be reduced.

[0110] In step S6, if the switch control unit 323 determines that the deviation does not exceed the prescribed value (NO), the switch control unit 323 determines whether the switch unit 33 is connected to the first control unit 321 (step S9). In step S9, if the switch control unit 323 determines that the switch unit 33 is connected to the first control unit 321 (Yes), the process returns to step S2. In addition, in step S9, if the switch control unit 323 determines that the switch unit 33 is not connected to the first control unit 321 (No), the switch unit 33 is switched from the feedback control system FBCS to the predictive control system PCS (step S10), and the process returns to step S2.

[0111] If the control amount changes little with respect to the process value, the control by the feedback control system FBCS will function effectively. However, in feedback control, the control is performed in a manner to eliminate the deviation of the current value of the control amount with respect to the target value. Therefore, if the control cannot immediately follow the change of the target value and a delay occurs, it is difficult to eliminate the deviation, and hunting or overshoot is likely to occur.

[0112] In contrast, in the control based on the prediction value performed by the prediction control system PCS, the expansion of the deviation is predicted, and the control amount is controlled using the prediction value at a time point when there is a sign of a small deviation. Thus, the deviation can be controlled to be small.

[0113] <Control operation details>

[0114] The control operation of the control device 3 will be described in detail. Here, an example in which the temperature of the outlet steam of the steam generating device 2, that is, the outlet steam of the tertiary superheater 233 is controlled as a control variable will be described.

[0115] The prediction model generated by the prediction model generation device 4 is a regression equation of multiple regression analysis. In the regression equation, the target variable is the temperature of the outlet steam of the tertiary superheater 233 (hereinafter referred to as "outlet steam temperature"), and as the process value, i.e., the explanatory variable, the flow rate of the exhaust gas in the discharge section 1b of the incinerator 1 (the measured value of the flow meter 272), the temperature of the exhaust gas, etc. are used.

[0116] The prediction unit 31 calculates and predicts the predicted value of the outlet steam temperature by applying the acquired process value as an explanatory variable to the regression equation as a prediction model. The first control unit 321 in the control unit 32 calculates the opening of the secondary water injection valve 252 as an input value based on the predicted value.

[0117] In simple terms, when, for example, the outlet steam temperature of a certain value is directly predicted as the predicted value, the first control unit 321 calculates the difference between the current value of the outlet steam temperature and the predicted value, and outputs the value of the opening corresponding to the calculated difference using a table that associates the difference with the opening. Alternatively, the first control unit 321 performs PID control based on the deviation between the current value of the control amount and the predicted value, thereby calculating the input value. Specifically, P (proportional) control is mainly applied to the deviation between the current value of the outlet steam temperature and the predicted value, and at least one of I (integral) control and D (differential) control is applied as needed to calculate the input value. In this way, compared with the simple calculation of the input value, the calculation of the input value based on PID control is advantageous in that it is easy to reflect the influence of various disturbances.

[0118] The first control unit 321 provides the input value calculated as described above to the secondary water injection valve 252. As a result, the secondary water injection valve 252 drives the valve to increase or decrease the opening provided as the input value. As a result, the amount of water supplied to the tertiary superheater 233 increases or decreases according to the changed opening of the secondary water injection valve 252, and the outlet steam temperature changes accordingly.

[0119] In this way, in the control based on the predicted value, the control is performed based on the predicted value predicted from a plurality of process values ​​that affect the outlet steam temperature. Thus, the outlet steam temperature can be controlled so as to reduce the influence of the process value.

[0120] Here, when the prediction unit 31 is configured as described in (1) to (4), the following effects can be obtained.

[0121] (1) The prediction unit 31 predicts the change amount of the control amount from the current time to the first prescribed time as a predicted value, thereby adding the predicted change amount to the current value of the control amount. In this way, the predicted value of the control amount from the current time to the first prescribed time can be obtained. Therefore, the prediction unit 31 predicts the change amount after the first prescribed time based on the current value. Therefore, by setting the first prescribed time to be short, the control accuracy can be further improved.

[0122] Here, the current value of the outlet steam temperature is compared with the predicted value by setting the first predetermined time to one minute, two minutes, and three minutes, and the results are described. Figure 3 This is a graph showing a comparison between the current value of the outlet steam temperature (controlled variable) and the predicted value of the outlet steam temperature in one minute. Figure 4 It is a graph showing the comparison between the current value of the outlet steam temperature and the predicted value of the outlet steam temperature two minutes later. Figure 5 is a graph showing a comparison between the current value of the outlet steam temperature and the predicted value of the outlet steam temperature three minutes later.

[0123] like Figures 3 to 5 As shown in the figure, the predicted values ​​(dashed lines) after one minute, two minutes, and three minutes are slightly offset to the right relative to the current value (solid line) of the outlet steam temperature. In this way, it is found that it can be used without problems to control the outlet steam temperature based on the predicted values. As a result, it is confirmed that the deviation between the current value and the predicted value is improved compared with the deviation between the current value and the target value based on the conventional feedback control.

[0124] In addition, the smallest deviation between the current value and the predicted value was obtained in the predicted value after one minute, the second smallest deviation was obtained in the predicted value after two minutes, and the largest deviation was obtained in the predicted value after three minutes. Therefore, it can be said that the closer the future predicted value is to the current value, the higher the prediction accuracy becomes.

[0125] (2) The prediction unit 31 predicts the controlled quantity based on a prediction model, wherein the prediction model sets the difference between the value of the controlled quantity after the first specified time from the current time and the current value of the controlled quantity as a target variable, and sets the process value as an explanatory variable. Thus, a predicted value can be obtained by using a prediction model of a target variable that takes into account the delay time. As the delay time, if delay factors such as the delay of the measurement performed by the measuring instrument are combined, a time difference of about one minute to one and a half minutes will be generated. If such a time difference is taken into account, the first specified time is preferably set to about two minutes. In this way, by reflecting the delay time in the control, the controlled quantity can be controlled with higher accuracy.

[0126] (3) The explanatory variable is the difference between the current value of the process value and the value of the process value a second predetermined time ago from the current value. Thus, the time width for taking the difference is set according to the scale and characteristics of the incinerator equipment. For example, for each explanatory variable, this time width is set to the time width that can be controlled with the highest accuracy in the incinerator equipment. Thus, higher-precision control suitable for each incinerator equipment can be performed.

[0127] (4) The target variable is the difference between the value of the outlet steam temperature after the first predetermined time from the current time and the current value of the outlet steam temperature. Thus, the target variable taking the delay time into consideration is used and the predicted value is obtained by multiple regression analysis. Therefore, the outlet steam temperature can be controlled with higher accuracy.

[0128] In addition, when the prediction unit 31 is configured as described in (3), the first control unit 321 calculates the input value provided to the secondary water injection valve 252 based on the prediction value, and controls the opening of the secondary water injection valve 252 based on the input value. The first control unit 321 controls the opening according to the difference between the value of the outlet steam temperature after the first predetermined time from the current value and the current value of the outlet steam temperature by performing a graded control in a plurality of subdivided stages. For example, if the difference is +3°C, the first control unit 321 controls the opening so as to increase it by 3%.

[0129] Conventionally, such control is performed in feedback control, but in the present embodiment, it can be applied to control based on a predicted value. Thus, by correcting the near future outlet steam temperature set at the first predetermined time based on the predicted value, the accuracy of the control of the outlet steam temperature can be improved. Therefore, the stability of the control of the outlet steam temperature can be improved.

[0130] As an example of controlling the outlet steam temperature as a controlled quantity, in addition to controlling the opening of the secondary water injection valve 252, it can also be the incineration amount of the incinerator 1, the heat exchange amount between the steam and the low-temperature heat source, the temperature of the pipe through which the steam of the boiler 21 passes, etc. As described above, the incineration amount of the incinerator 1 can be adjusted by controlling the speed at which the waste supply device 12 supplies the waste. In addition, the heat exchange amount between the steam and the low-temperature heat source is the heat exchange amount of the heat exchanger that performs the heat exchange between the steam of the boiler 21 and the low-temperature heat source such as air and water in the pipe through which the steam passes. In addition, regarding the temperature of the pipe through which the steam passes, for example, it can be cooled by a Peltier device (temperature regulator), and on the other hand, it can be heated by a heater (temperature regulator). Therefore, it is sufficient to control the set temperatures of these temperature regulators.

[0131] In addition, in the present embodiment, as described above, an example of controlling the outlet steam temperature as a control variable is described, but the control variable controlled by the present embodiment is not limited to this, and for example, it may be the steam volume or the exhaust gas value (NOx value). When the steam volume is controlled as the target variable, as the explanatory variables, the steam volume (PV, MV), the exhaust gas flow rate, the exhaust gas temperature, the temperature in the incinerator 1, the water supply to the boiler 21, etc. can be listed. In addition, when the exhaust gas value is controlled as the target variable, as the explanatory variables, NOx (PV, MV), the temperature in the incinerator 1, the oxygen concentration of the exhaust gas, etc. can be listed.

[0132] In addition, when the prediction unit 31 is configured as described in (3), the first control unit 321 may also control the temperature of the combustion air supplied to the grate unit 13 (hereinafter referred to as the combustion air temperature) based on the predicted value of the outlet steam temperature. Specifically, the control amount is the outlet steam temperature, and the first control unit 321 calculates the input value provided to the air preheater 15 in the incinerator 1 based on the predicted value of the outlet steam temperature predicted by the prediction unit 31, and controls the temperature of the air preheater 15 based on the input value.

[0133] In this way, by linking the change in the predicted value of the outlet steam temperature with the change in the combustion air temperature and controlling the combustion air temperature, it is possible to stabilize the combustion temperature and the exhaust gas flow rate in the incinerator 1. As a result, the outlet steam temperature can be stabilized.

[0134] Furthermore, when the temperature of the grate unit 13, especially the temperature of the drying grate 131, measured by the thermometer 18 is 250° C. or higher, the first control unit 321 may control the combustion air temperature to be a fixed value of 20° C. Thus, damage to the grate unit 13 can be reduced.

[0135] In addition, the steam generating device 2 of the present embodiment has a three-stage superheating structure including the primary superheater 231 , the secondary superheater 232 , and the tertiary superheater 233 , but the present invention can also be applied to a two-stage superheating structure.

[0136] [Contribution to the Sustainable Development Goals (SDGs)]

[0137] According to the configuration of the embodiment, efficient operation of the incinerator facility 100 can be achieved. Therefore, it is possible to contribute to the achievement of Goal 9 of the Sustainable Development Goals (SDGs), "Building the foundation for industrial and technological innovation (infrastructure, system preparation, etc.)".

[0138] 〔Software-based implementation example〕

[0139] The functions of the control device 3 and the prediction model generation device 4 (hereinafter referred to as “devices”) can be realized by a program for causing a computer to function as the devices and for causing a computer to function as each control block of the devices.

[0140] In this case, the device includes a computer having at least one processor and at least one storage device (e.g., memory) as hardware for executing the program. The functions described in the embodiment are realized by executing the program using the processor and the storage device.

[0141] The program may be recorded in one or more non-transitory recording media that can be read by a computer. The device may include the recording medium or not. In the latter case, the program may be supplied to the device via any transmission medium, whether wired or wireless.

[0142] In addition, part or all of the functions of each control block can also be realized by a logic circuit. For example, an integrated circuit having a logic circuit that functions as each control block is also included in the scope of the present invention. In addition, the functions of each control block can also be realized by, for example, a quantum computer.

[0143] In addition, each process described in the embodiment may also be performed by artificial intelligence (AI). In this case, the AI ​​may be operated by the control device or by other devices (e.g., edge computers or cloud servers).

[0144] 〔Summarize〕

[0145] As described above, the control device of form 1 of the present invention controls a control quantity in an incinerator device, wherein the incinerator device includes: an incinerator; a boiler that uses exhaust gas from the incinerator to generate steam; a superheater that superheats the steam generated by the boiler; and a desuperheater that reduces the temperature of the steam superheated by the superheater in the front section, and the control device includes: a prediction unit that predicts a predicted value of the control quantity at a control time point based on a plurality of process values ​​in the incinerator device that affect the control quantity; and a control unit that calculates an input value indicating the size of an input provided to the control object for controlling the control quantity based on the predicted value, and controls the control quantity based on the input value.

[0146] According to the above configuration, control is performed based on the predicted value predicted from a plurality of process values ​​that affect the controlled variable. Thus, the controlled variable can be controlled so as to reduce the influence of the process value.

[0147] The control device of aspect 2 of the present invention may be such that, in aspect 1, the prediction unit predicts a change amount of the control amount from the present time to a first predetermined time later as the prediction value.

[0148] According to the above configuration, the change amount after the first predetermined time based on the current value is predicted. Therefore, by setting the first predetermined time to be short, the control accuracy can be further improved.

[0149] The control device of form 3 of the present invention may be: in form 2, the first prescribed time is a delay time based on a delay element of control, the prediction unit predicts the control quantity based on a prediction model, the prediction model sets the difference between the value of the control quantity after the first prescribed time from the current time and the current value of the control quantity as the target variable, and sets the process value as the explanatory variable.

[0150] According to the above configuration, a prediction value is obtained by using a prediction model of a target variable taking the delay time into consideration, thereby enabling the controlled amount to be controlled with higher accuracy.

[0151] The control device of aspect 4 of the present invention may be: in aspect 3, the explanatory variable is a difference between a current value of the process value and a value of the process value a second predetermined time ago from the current value.

[0152] According to the above configuration, the time width for taking the difference between process values ​​is set as the explanatory variable according to the scale and characteristics of the incinerator facility, thereby enabling more accurate control suitable for each incinerator facility.

[0153] A control device according to a fifth aspect of the present invention may be configured such that, in the third aspect, the target variable is a difference between a value of the steam temperature after the first predetermined time from the present time and a present value of the steam temperature.

[0154] According to the above configuration, the target variable taking the delay time into consideration is used to obtain a predicted value through a prediction model, thereby enabling the steam temperature to be controlled with higher accuracy.

[0155] The control device of aspect 6 of the present invention may be: in aspect 5, the explanatory variable is a difference between a current value of the process value and a value of the process value a second predetermined time ago from the current value.

[0156] According to the above configuration, the time width for taking the difference between process values ​​is set as the explanatory variable according to the scale and characteristics of the incinerator facility, thereby enabling more accurate control suitable for each incinerator facility.

[0157] The control device of form 7 of the present invention may be: in form 3, the control quantity is the steam temperature at the outlet of the superheater, the control unit calculates the input value provided to the water injection valve based on the predicted value, and controls the opening of the water injection valve based on the input value in multiple stages corresponding to the difference in the steam temperature, wherein the water injection valve adjusts the amount of cooling water injected into the desuperheater.

[0158] The control device of form 8 of the present invention may be: in form 3, the control quantity is the steam temperature at the outlet of the superheater, the control unit calculates the input value provided to the waste supply device based on the predicted value, and based on the input value, controls the speed at which the waste supply device supplies waste in multiple stages corresponding to the difference in the steam temperature, wherein the waste supply device adjusts the incineration amount of the waste in the incinerator.

[0159] The control device of form 9 of the present invention may be: in form 3, the control quantity is the steam temperature at the outlet of the superheater, the control unit calculates the input value provided to the heat exchanger for adjusting the heat exchange quantity of the heat exchanger based on the predicted value, and controls the heat exchange quantity in multiple stages corresponding to the difference in the steam temperature based on the input value, wherein the heat exchanger exchanges heat with the low-temperature heat source through the steam of the boiler.

[0160] The control device of form 10 of the present invention may be: in form 3, the control quantity is the steam temperature at the outlet of the superheater, the control unit calculates the input value provided to the temperature regulator based on the predicted value, and controls the set temperature of the temperature regulator in multiple stages corresponding to the difference in the steam temperature based on the input value, wherein the temperature regulator adjusts the temperature of the piping through which the steam of the boiler passes.

[0161] According to the configurations of the seventh to tenth aspects, the control accuracy of the steam temperature at the outlet of the superheater can be improved.

[0162] The control device of form 11 of the present invention may be: in form 3, the incinerator has a grate and an air preheater, the air preheater adjusts the temperature of the combustion air supplied to the grate, the control quantity is the steam temperature at the outlet of the superheater, and the control unit calculates the input value provided to the air preheater based on the predicted value, and controls the temperature of the air preheater based on the input value.

[0163] According to the above configuration, the combustion temperature or exhaust gas flow rate in the incinerator can be stabilized by controlling the combustion air temperature by linking the change in the predicted value of the steam temperature at the outlet of the superheater with the change in the combustion air temperature. As a result, the outlet steam temperature can be stabilized.

[0164] The control device of form 12 of the present invention may be: in any one of forms 1 to 11, when the control unit uses a predictive control system that controls the control amount based on the predicted value, when the deviation of the current value of the control amount relative to the predicted value exceeds a specified value, it switches to a feedback control system that controls the control amount to make the control amount consistent with the target value.

[0165] According to the above configuration, when the control amount changes too much under the control performed by the predictive control system, the control amount can be reduced under the control performed by the feedback control system.

[0166] The incinerator equipment of form 13 of the present invention includes: a control device according to any one of forms 1 to 8; an incinerator; a boiler that uses exhaust gas from the incinerator to generate steam; a superheater that superheats the steam generated by the boiler; and the desuperheater that reduces the temperature of the steam superheated by the superheater.

[0167] The prediction model generating device of form 14 of the present invention generates the prediction model used in the control device according to any one of forms 3 to 11, and includes a weight determination unit, which takes the measured process value as input data and the measured control quantity as output data, and determines the weight of the prediction model by learning so as to minimize the deviation of the prediction value predicted using the input data relative to the output data.

[0168] According to the above structure, a prediction model with high prediction accuracy can be generated.

[0169] The prediction model generating device of form 15 of the present invention may be: in form 14, the explanatory variable is the difference between the current value of the process value and the value of the process value from the current time to a second specified time ago, and the prediction model generating device also includes a time setting unit, which sets the second specified time for each process value so that the accuracy of the prediction model becomes the highest.

[0170] According to the above configuration, it is possible to improve the prediction accuracy of the prediction unit using the prediction model.

[0171] The control method of form 16 of the present invention controls the control quantity of a control object in an incinerator device, wherein the incinerator device includes: an incinerator; a boiler that uses exhaust gas from the incinerator to generate steam; at least two superheaters that superheat the steam generated by the boiler; and a desuperheater that reduces the temperature of the steam superheated by the front superheater between two adjacent superheaters. The control method includes: a prediction step that predicts a predicted value of the control quantity at a control time point based on multiple process values ​​in the incinerator device that affect the control quantity; and a control step that calculates an input value indicating the size of an input provided to the control object in order to control the control quantity based on the predicted value, and controls the control quantity based on the input value.

[0172] Thus, similar to the control device of form 1, the control amount can be controlled to reduce the influence of the process value.

[0173] [Additional Notes]

[0174] The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims. In addition, embodiments obtained by appropriately combining different technical means disclosed in the embodiments are also included in the technical scope of the present invention.

[0175] Description of Figure Numbers

[0176] 1Incinerator

[0177] 3. Control Device

[0178] 4 Prediction model generation device

[0179] 31 Forecast Department

[0180] 41 Weight determination department

[0181] 42 Time setting unit

[0182] 100 Incinerator Equipment

[0183] 131 Drying grate (grate)

[0184] 132 Combustion grate (grate)

[0185] 133 Post-combustion grate (grate)

[0186] 241 primary desuperheater (desuperheater)

[0187] 242 Secondary desuperheater (desuperheater)

[0188] 231 primary superheater (superheater)

[0189] 232 Secondary superheater (superheater)

[0190] 233 tertiary superheater (superheater)

[0191] 251 primary water injection valve (water injection valve)

[0192] 252 Secondary water injection valve (water injection valve)

[0193] PCS Predictive Control System

[0194] FBCS Feedback Control System

Claims

1. A control device for controlling a control quantity in an incinerator device, wherein the incinerator device comprises: Incinerators; a boiler for generating steam using exhaust gas from the incinerator; a superheater for superheating steam generated by the boiler; and a desuperheater for lowering the temperature of the steam superheated by the superheater, wherein the control device is characterized by comprising: A prediction unit that predicts a predicted value of the control amount at a control time point based on a plurality of process values ​​in the incinerator equipment that affect the control amount; as well as The control unit calculates an input value indicating a magnitude of an input to be provided to a controlled object for controlling the controlled amount based on the predicted value, and controls the controlled amount based on the input value.

2. The control device according to claim 1, characterized in that: The prediction unit predicts a change amount of the control amount from the present time to a first predetermined time later as the predicted value.

3. The control device according to claim 2, characterized in that: The first prescribed time is a delay time based on a delay element of control, The prediction unit predicts the controlled variable based on a prediction model that uses a difference between a value of the controlled variable after the first predetermined time from the present and a current value of the controlled variable as a target variable and uses the process value as an explanatory variable.

4. The control device according to claim 3, characterized in that: The explanatory variable is a difference between a current value of the process value and a value of the process value a second predetermined time ago from the current value.

5. The control device according to claim 3, characterized in that: The controlled variable is the steam temperature at the outlet of the superheater, The target variable is a difference between a value of the steam temperature after the first predetermined time from the present and a present value of the steam temperature.

6. The control device according to claim 5, characterized in that: The explanatory variable is a difference between a current value of the process value and a value of the process value a second predetermined time ago from the current value.

7. The control device according to claim 3, characterized in that: The controlled variable is the steam temperature at the outlet of the superheater. The control unit calculates the input value provided to the water injection valve based on the predicted value, and controls the opening of the water injection valve in multiple stages corresponding to the difference in the steam temperature based on the input value, wherein the water injection valve adjusts the amount of cooling water injected into the desuperheater.

8. The control device according to claim 3, characterized in that: The controlled variable is the steam temperature at the outlet of the superheater. The control unit calculates the input value provided to the waste supply device based on the predicted value, and controls the speed at which the waste supply device supplies waste in multiple stages corresponding to the difference in the steam temperature based on the input value, wherein the waste supply device adjusts the incineration amount of the waste in the incinerator.

9. The control device according to claim 3, characterized in that: The controlled variable is the steam temperature at the outlet of the superheater. The control unit calculates the input value provided to the heat exchanger for adjusting the heat exchange amount of the heat exchanger based on the predicted value, and controls the heat exchange amount in multiple stages corresponding to the difference in the steam temperature based on the input value, wherein the heat exchanger exchanges heat with the low-temperature heat source through the steam of the boiler.

10. The control device according to claim 3, characterized in that: The controlled variable is the steam temperature at the outlet of the superheater. The control unit calculates the input value provided to the temperature regulator based on the predicted value, and controls the set temperature of the temperature regulator in multiple stages corresponding to the difference in the steam temperature based on the input value, wherein the temperature regulator adjusts the temperature of the piping through which the steam of the boiler passes.

11. The control device according to claim 3, characterized in that: The incinerator includes a grate and an air preheater, wherein the air preheater adjusts the temperature of the combustion air supplied to the grate. The controlled variable is the steam temperature at the outlet of the superheater. The control unit calculates the input value to be provided to the air preheater based on the predicted value, and controls the temperature of the air preheater based on the input value.

12. The control device according to claim 1, characterized in that: When the control unit uses a predictive control system that controls the control amount based on the predicted value, when the deviation of the current value of the control amount with respect to the predicted value exceeds a specified value, the control unit switches to a feedback control system that controls the control amount to make the control amount consistent with the target value.

13. An incinerator device, characterized in that include: A control device as claimed in any one of claims 1 to 12; Incinerators; a boiler for generating steam using exhaust gas from the incinerator; a superheater for superheating steam generated by the boiler; and The desuperheater lowers the temperature of the steam superheated by the superheater.

14. A prediction model generating device, which generates the prediction model used in the control device according to any one of claims 3 to 11, characterized in that include: The weight determination unit uses the measured process value as input data and the measured control amount as output data, and determines the weight of the prediction model by learning so as to minimize the deviation of the predicted value predicted using the input data relative to the output data.

15. The prediction model generating device according to claim 14, characterized in that: The explanatory variable is a difference between a current value of the process value and a value of the process value a second predetermined time ago from the current value. The prediction model generation device further includes a time setting unit configured to set the second predetermined time for each process value so that the accuracy of the prediction model becomes the highest.

16. A control method for controlling a control variable in an incinerator device, the incinerator device comprising: Incinerators; a boiler for generating steam using exhaust gas from the incinerator; a superheater for superheating steam generated by the boiler; and a desuperheater for lowering the temperature of the steam superheated by the superheater, wherein the control method is characterized by comprising: A prediction step of predicting a predicted value of the control amount at a control time point based on a plurality of process values ​​in the incinerator equipment that affect the control amount; as well as The control step calculates an input value indicating a magnitude of an input to be provided to a control object for controlling the controlled variable based on the predicted value, and controls the controlled variable based on the input value.

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