JP5856899B2 - Coal-fired power plant control equipment - Google Patents

Description

The present invention relates to a control device for a coal-fired power plant that generates power using coal as fuel.

  In a coal-fired power plant that generates power using coal as a fuel, solid coal is pulverized by a plurality of pulverized coal machines (mills) installed in the plant to produce fine particulate pulverized coal. Since the quality of coal varies depending on the production area and climatic conditions, it is necessary to homogenize pulverized coal properties such as particle size and moisture as much as possible. For this reason, in the control apparatus of a coal thermal power plant, control which changes mill operation conditions suitably according to the property of coal is implemented based on coal information registered beforehand according to an operation plan.

On the other hand, in recent years, there are an increasing number of plants that use mixed fuels of different qualities because it is difficult to always ensure fuels of the same quality due to soaring fuel prices. Furthermore, from the viewpoint of reducing carbon dioxide (CO ₂ ) emissions into the atmosphere for the purpose of protecting the global environment, it is expected that the number of plants that use wood biomass mixed with fuel will increase in the future.

  In such a coal-fired power plant that uses a mixture of fuels, it is expected that the properties of the coal being processed will be different for each mill, and adaptive mill control according to each coal property is required. Furthermore, when coal in which a plurality of types are mixed is supplied to one mill, it is unclear what proportion of these coals are mixed. For this reason, unlike the coal information in which the property of the coal actually processed is registered in advance, there is a possibility that appropriate mill control cannot be executed.

  As a technique in view of the above circumstances, Patent Document 1 estimates in real time the properties of coal such as moisture and grindability based on mill measurement information, and adaptively controls mill operation conditions based on the estimated information. Techniques to do this are disclosed.

JP 2003-340299 A

  Even when fuels are mixed and used by the technology disclosed in Patent Document 1, appropriate mill control is performed based on coal information estimated from mill measurement information, and variation in pulverized coal characteristics of fuel is reduced. Can do.

  However, even if suitable pulverized coal is obtained in the mill, there is no guarantee that the desired combustion characteristics are actually obtained when the pulverized coal is burned in the boiler downstream of the mill. For this reason, in a boiler furnace, a combustion balance deteriorates by arrangement | positioning of the burner which burns the pulverized coal supplied from a mill, As a result, the operation efficiency of a plant may deteriorate.

  The present invention has been invented in view of the above problems, and an object thereof is to provide a control device capable of determining mill operation conditions for the purpose of maximizing plant operation efficiency in a coal-fired power plant. It is to be.

  The control apparatus for a coal-fired power plant according to the present invention has the following characteristics.

  From a coal-fired power plant comprising a mill that pulverizes coal into pulverized coal and a boiler that burns pulverized coal, a measurement signal representing a state quantity of the coal-fired power plant is acquired, and the coal-fired power plant is obtained using the measurement signal. In a control apparatus for a coal-fired power plant that controls the control signal, a control signal generation unit that generates a control signal to be given to the coal-fired power plant using the measurement signal, and a measurement signal database that stores data included in the measurement signal And a coal information management database for storing information on the coal, a mill characteristic information database for storing information on the characteristics of the mill, the measurement signal database, the coal information management database, and the mill characteristic information database. A mill characteristic evaluation unit for calculating the characteristics of the mill using the obtained information, and the mill characteristics The mill operation calculation unit that calculates the operation condition of the mill using the characteristics of the mill calculated by the valence unit, the calculation result database that stores the operation condition of the mill calculated by the mill operation calculation unit, and the coal A control logic database for storing control logic for the thermal power plant. The coal information management database stores at least a coal moisture value, a fuel ratio, and an HGI that is a pulverization index as information on the coal. The control signal generation unit is configured to generate the control signal using information stored in the calculation result database and the control logic database.

  According to the present invention, in a coal-fired power plant, control that optimizes not only the operation efficiency of the mill but also the combustion state in the boiler furnace is possible. As a result, the operating efficiency of the entire plant can be maximized even when the properties of the coal and plant operating conditions vary.

It is a block diagram which shows the structure of the control apparatus of the coal-fired power plant by the Example of this invention. It is a block diagram which shows the outline of the coal-fired power plant to which the control apparatus by a present Example is applied. It is a figure which shows the structure of the mill with which a coal thermal power plant is provided. It is a flowchart which shows the procedure of control in the control apparatus of the coal-fired power plant by a present Example. It is a block diagram which shows the function of a mill characteristic evaluation part. It is a block diagram which shows the function of a mill basic performance calculation function. Mill is a diagram showing the function of the functional module F _{1 (x)} of the basic performance calculator. It is a figure which shows the function characteristic of the moisture correction amount calculation module _F1a (x). Mill is a diagram showing the function of the functional module F _{2 (x)} of the basic performance calculator. It is a figure which shows the function characteristic of fuel ratio correction _| amendment module _F2b (x). Mill is a diagram showing the function of the functional module F _{3 (x)} of the basic performance calculator. Mill is a diagram showing the function of the functional module F _{4 (x)} of the basic performance calculator. Mill is a diagram showing a function characteristic of the functional module F _{8 (x)} of the basic performance calculator. It is a block diagram which shows the function of a mill efficiency calculation function. It is a flowchart showing the procedure of operation | movement of a mill characteristic evaluation part. It is a flowchart showing the procedure of operation | movement of a mill operation calculation part. It is the schematic which shows grouping of a mill. It is an example of the setting screen of a mill group displayed on an image display device, when executing a mill operation calculation part. It is an example of the display screen of the mill evaluation value trend displayed on an image display device, when confirming the trend of mill characteristic information. It is an example of the display screen of the trend of the operational efficiency balance and the plant efficiency displayed on the image display device when confirming the trend of the average operational efficiency of each mill group and the operational efficiency of the whole plant.

  First, an outline of a control apparatus for a coal-fired power plant according to the present invention will be described. Details of this control device will be described in the embodiments described later.

  A control apparatus for a coal-fired power plant according to the present invention includes a measurement signal database, a coal information management database, a mill characteristic information database, a mill characteristic evaluation unit, a mill operation calculation unit, a calculation result database, a control logic database, A control signal generating unit, acquiring a measurement signal that is a state quantity of the plant from the coal-fired power plant, and generating a control signal for controlling the coal-fired power plant using the measurement signal. At this time, the mill characteristic evaluation unit and the mill operation calculation unit calculate the optimum operation condition of the mill in real time, and the control signal generation unit generates a control signal based on this.

  The measurement signal database stores measurement data included in the measurement signal and used when generating the control signal. The coal information management database stores information (coal information) on coal as fuel. The mill characteristic information database includes operating coal properties (moisture, fuel ratio, estimated values of grindability index HGI) and plant mill characteristic information (C / A value, mill capacity, mill basic performance information). Preservation of atomization index, mill power and mill operation efficiency). The mill characteristic evaluation unit calculates mill characteristics (basic performance information and operation efficiency of the mill) using information stored in the measurement signal database, the coal information management database, and the mill characteristic information database. The mill operation calculation unit calculates mill operation conditions using the mill characteristics calculated by the mill characteristic evaluation unit. The calculation result database stores mill operation conditions calculated by the mill operation calculation unit. The control logic database stores control logic for the plant. This control logic includes logic for controlling the mill using the value of the mill operation condition calculated by the mill operation calculation unit. The control signal generation unit generates a control signal for the plant using information stored in the calculation result database and the control logic database.

  With such a configuration, the control device for a coal-fired power plant according to the present invention burns pulverized coal in the boiler, coal information (coal properties) estimated in real time based on mill measurement information, and the operation state of the mill. By considering the arrangement of the burner and the combustion balance, it is possible to control not only the operation efficiency of the mill but also the combustion state in the boiler furnace. As a result, even when the properties of the coal and the plant operating conditions vary, the operation efficiency of the entire plant can always be maximized in accordance with the properties of the supplied coal and the plant operating conditions.

  The measurement signal includes the rotation speed of the mill classifier, the mill roller pressure oil pressure, the mill outlet air temperature (hereinafter referred to as “mill outlet temperature”), the differential pressure between the mill inlet and outlet (hereinafter referred to as “mill differential pressure”). ), Mill roller lift amount, amount of coal supplied to the mill (hereinafter referred to as “coal feeder flow rate”), primary air flow rate and secondary air flow rate supplied to the boiler, boiler feed water flow rate, boiler Feed water temperature, boiler feed water pressure, boiler steam temperature, boiler steam pressure, boiler steam flow, boiler exhaust gas temperature, concentration of environmentally hazardous substances contained in boiler exhaust gas (for example, nitrogen oxide (NOx) And a signal representing at least one of the exhaust gas recirculation flow rate of the boiler and the like.

  The control signals are: mill classifier rotation speed, mill roller pressure oil pressure, amount of coal supply to the mill, boiler air flow rate, boiler air damper opening, boiler exhaust gas recirculation flow rate, boiler feed water flow rate, turbine A signal for determining at least one of the governor opening degrees is included.

  The mill characteristic evaluation unit has a mill basic performance calculation function and a mill efficiency calculation function. The mill basic performance calculation function inputs information stored in the measurement signal database, the coal information management database, and the mill characteristic information database, and calculates the mill basic performance information. The mill basic performance information includes a mill capacity that is the pulverized coal supply amount supplied to the boiler by the mill, a C / A value obtained by dividing the mill capacity by the primary air flow rate, a pulverization index that represents the degree of pulverization of the pulverized coal, And mill power, which is the power consumed by the mill. The mill efficiency calculation function calculates the operation efficiency for each mill based on the basic mill performance information.

  The mill basic performance calculation function inputs a mill outlet temperature and a default moisture described later in the measurement signal, and obtains a difference between the mill outlet temperature and a predetermined reference set temperature. When this difference takes a negative value, the moisture correction amount is set to a positive value. When this difference takes a positive value, an operation is performed to set the moisture correction amount to a negative value, and the moisture correction amount is added to the default moisture. In this way, the water content of the coal currently being processed by the mill is estimated.

  Furthermore, the mill basic performance calculation function includes the previous value of C / A (the previous calculation result and the value stored in the mill characteristic information database), the previous value of the mill capacity (the previous calculation result and the mill characteristic information). Value stored in the database), previous value of the atomization index (the previous calculation result and value stored in the mill characteristic information database), default fuel ratio included in the coal information, and estimated fuel ratio The standard NOx concentration is calculated using a statistical method based on past performance data with respect to the previous value (the previous calculation result and the value stored in the coal information management database). Then, the difference between the standard NOx concentration and the NOx concentration included in the measurement information is obtained. When this difference takes a negative value, the fuel ratio correction amount is set to a negative value, and when this difference takes a positive value, calculation is performed to set the fuel ratio correction amount to a positive value. Is added to the previous value. In this way, the fuel ratio of the coal currently being processed by the mill is estimated.

  Furthermore, the mill basic performance calculation function calculates the difference between the primary air flow rate, the coal feeder flow rate, the mill roller pressurization oil pressure included in the measurement signal, and the predetermined reference amounts of these amounts for each amount. Ask. With respect to the previous value of the estimated value of HGI (Hardgrove Grindability Index) which is a value indicating the difference and the ease of cracking of coal (the value calculated in the previous calculation and stored in the mill characteristic information database) Then, the mill roller lift amount correction amount is calculated using a statistical method based on past performance data. The mill roller lift amount in the standard operation state (reference mill roller lift amount) is estimated by adding the mill roller lift amount correction amount to the mill roller lift amount included in the measurement signal.

  Furthermore, the mill basic performance calculation function calculates the difference between the primary air flow rate, the coal feeder flow rate, the mill classifier rotation speed included in the measurement signal, and the predetermined reference amounts of these amounts for each amount. Ask. A mil differential pressure correction amount is calculated for these differences and the previous value of the estimated HGI value using a statistical method based on past performance data. Then, the mill differential pressure in the standard operation state (reference mil differential pressure) is estimated by adding the mill differential pressure correction amount to the mill differential pressure included in the measurement signal.

  Furthermore, the mill basic performance calculation function uses a statistical method based on past performance data for the estimated coal moisture, coal fuel ratio, reference mill roller lift, and reference mill differential pressure. Estimate the HGI of the coal currently being processed.

  Furthermore, the mill basic performance calculation function uses a statistical method based on past performance data for the estimated HGI and the mill roller pressurization oil pressure and the mill classifier rotation speed included in the measurement signal. Is estimated. The coal output rate is a value indicating the ratio of the amount of pulverized coal supplied to the amount of coal supplied to the mill.

  Furthermore, the mill basic performance calculation function uses a statistical method based on past performance data for the estimated HGI and the mill roller pressure oil pressure and the mill classifier rotation speed included in the measurement signal. Estimate the conversion index.

  The mill efficiency calculation function uses a statistical method based on past performance data for the C / A value, atomization index, and mill capacity calculated by the mill basic performance calculation function. Estimate the burning rate.

  Furthermore, a mill efficiency calculation function calculates the combustion efficiency in the case of burning the pulverized coal supplied from a mill from the estimated combustion rate and coal information.

  Further, the mill efficiency calculation function calculates the mill operation efficiency from the calculated combustion efficiency and the mill capacity and power calculated by the mill basic performance calculation function. The mill operation efficiency is a value obtained by subtracting the loss due to the mill power from the combustion efficiency.

  The mill operation calculation unit classifies the mills into a plurality of groups. Then, for the classified group, an index obtained from the operating efficiency of mills belonging to any one group j and an index considering the balance of operating efficiency between this group j and all other groups k (≠ j) The operation function of the mill belonging to this group j is searched using the optimum search method so that the evaluation function is calculated by the sum of and the value of the evaluation function is maximized. When classifying mills into a plurality of groups, the balance of operation efficiency between mills can be taken into account based on burner arrangement and operation information for burning pulverized coal supplied from the mill.

  The control device includes an input / output unit, and can be connected to the image display device via the input / output unit. The input / output unit transmits and receives information to and from the image display device. For example, the input / output unit is a measurement signal database, a coal information management database, a mill characteristic information database, a mill operation calculation information database, which will be described later, and a function for displaying information stored in a calculation result database on an image display device, In order to set the function for displaying the results calculated by the mill characteristic evaluation unit and the mill operation calculation unit on the image display device and the execution conditions necessary for checking the information stored in the database via the image display device. It has the function of.

  The above-described configuration, function, processing unit, processing unit, and the like may be realized by hardware, for example, by designing a part or all of them with an integrated circuit. In addition, the configuration, function, processing unit, processing means, and the like described above may be realized by software by causing the processor to interpret and execute a program that realizes each function. Information such as programs, tables, files, measurement information, and calculation information for realizing each function is stored in a recording device such as a memory, a hard disk, and an SSD (Solid State Drive), or an IC card, an SD card, and a DVD. It can be recorded on a recording medium. Therefore, each process and each configuration can realize each function as a processing unit, a processing unit, a program module, and the like.

  Next, an embodiment of a control device for a coal-fired power plant according to the present invention will be described with reference to the drawings.

  The control apparatus of the coal-fired power plant by the Example of this invention is demonstrated with reference to drawings.

  FIG. 1 is a block diagram showing a configuration of a control device for a coal-fired power plant according to an embodiment of the present invention. As shown in FIG. 1, the control device 200 controls the coal-fired power plant 100.

  The control device 200 of the coal-fired power plant 100 includes an input / output unit 800 and is connected to the maintenance tool 910 via the input / output unit 800. An operator of the coal-fired power plant 100 can control the control device 200 via an external input device 900 and an image display device 920 (for example, a CRT display) connected to the maintenance tool 910.

  The control device 200 includes a mill characteristic evaluation unit 300, a mill operation calculation unit 400, and a control signal generation unit 500 as arithmetic units. The mill characteristic evaluation unit 300 has individual mill characteristic evaluation units according to the number of mills installed in the coal-fired power plant 100. FIG. 1 shows a case where each of mills A to X includes A mill characteristic evaluation units 301a to 301x as individual mill characteristic evaluation units. The mill operation calculation unit 400 includes a group operation calculation unit that calculates operation conditions of mills classified into groups for each group. In FIG. 1, the group operation calculation unit includes group 1 operation calculation units 401-1 to 401 -n for groups 1 to N, respectively. The mills can be classified into arbitrarily combined groups in consideration of the plant configuration and operating characteristics.

  The control device 200 includes a measurement signal database 210, a coal information management database 220, a mill characteristic information database 230, a mill operation calculation information database 240, a calculation result database 250, and a control logic database 260 as a database (DB).

  Moreover, the control apparatus 200 is provided with the external input interface 201 and the external output interface 202 as an interface with the exterior (coal-fired power plant 100).

  The control device 200 acquires the measurement signal 1 obtained by measuring various state quantities of the coal-fired power plant 100 via the external input interface 201 and stores the measurement signal 1 in the measurement signal database 210 as the measurement signal 2. The measurement signal database 210 is also included in the measurement signal 2 and stores measurement data used when the control signal 14 is generated.

  In addition, the control device 200 outputs the control signal 14 generated by the control signal generation unit 500 to the coal-fired power plant 100 as the control signal 15 via the external output interface 202. The control signal 15 is a signal for controlling the coal-fired power plant 100, for example, a signal for controlling the supplied coal flow rate, air flow rate, and the like.

  The mill characteristic evaluation unit 300 includes measurement data 4 stored in the measurement signal database 210, coal information 5 stored in the coal information management database 220, mill characteristic information 6 stored in the mill characteristic information database 230, and mill operation calculation. The mill operation condition 9 output by the unit 400 is input, and the mill characteristic information 7 and the mill operation efficiency information 8 are calculated for each mill based on the characteristics of each mill such as the amount of coal output, the degree of atomization, and the power consumption. To do. The mill characteristic information 7 is stored in the mill characteristic information database 230. The mill operation efficiency information 8 is input to the mill operation calculation unit 400. The coal information 5 stored in the coal information management database 220 includes information on the brand, composition and calorific value of the coal. The coal information 5 is registered by an operator of the plant 100 in accordance with a predetermined fuel operation plan.

The mill operation calculation unit 400 uses the mill operation efficiency information 8 input from the mill characteristic evaluation unit 300 and the mill operation calculation information data 10 stored in the mill operation calculation information database 240, for each mill group. 9 and 11 are calculated using the optimum search method. The mill operation calculation information data 10 includes a determination flag θ _jk and parameters necessary for operating a search algorithm for searching for an operation condition of the mill group. The determination flag θ _jk and the search algorithm will be described later together with a detailed description of the function of the mill operation calculation unit 400. The calculated mill operation conditions 9 and 11 are output to the mill characteristic evaluation unit 300 and stored in the calculation result database 250.

  The control signal generation unit 500 inputs the measurement data 3 from the measurement signal database 210, the calculation result data 12 from the calculation result database 250, and the control logic data 13 from the control logic database 260, respectively. A control signal 14 for controlling the state is generated.

  The control logic database 260 stores a control circuit that calculates the control logic data 13. As a control circuit for calculating the control logic data 13, publicly known PI (proportional / integral) control can be used. The calculation result data 12 stored in the calculation result database 250 includes information related to the correction value of the mill operation condition for the control logic.

  As described above, based on the mill operation efficiency information 8 calculated by the mill characteristic evaluation unit 300, the mill operation calculation unit 400 sets the mill operation condition 11 for each group in which the mills are classified based on the configuration and operation characteristics of the plant 100. calculate. Then, based on the calculation result, the control signal generation unit 500 generates the control signal 14 for the plant 100. Therefore, the control device 200 can execute appropriate mill control according to the mill characteristics estimated in real time, and can achieve improvement in plant efficiency and reduction in fuel consumption. As a result, the operating efficiency of the entire plant can be maximized even when the properties of the coal and plant operating conditions vary.

  The functions of the mill characteristic evaluation unit 300 and the mill operation calculation unit 400 will be described later in detail.

  An operator of the plant 100 uses an external input device 900 including a keyboard 901 and a mouse 902, a maintenance tool 910 that can transmit and receive data to and from the control device 200, and an image display device 920, thereby providing various databases included in the control device 200. Access stored information. The input / output unit 800 of the control device 200 transmits / receives the input / output data information 90 to / from the maintenance tool 910.

  The maintenance tool 910 includes an external input interface 911, a data transmission / reception processing unit 912, and an external output interface 913, and can transmit / receive data to / from the control device 200 via the data transmission / reception processing unit 912.

  The maintenance tool input signal 91 generated by the external input device 900 is taken into the maintenance tool 910 via the external input interface 911. The data transmission / reception processing unit 912 of the maintenance tool 910 acquires the input / output data information 90 from the control device 200 according to the information of the maintenance tool input signal 92.

  Further, the data transmission / reception processing unit 912 is necessary for checking the calculation results obtained by the plant efficiency calculation unit 300, the mill operation calculation unit 400, and the control signal generation unit 500 of the control device 200 according to the information of the maintenance tool input signal 92. The input / output data information 90 is output.

  The data transmission / reception processing unit 912 transmits a maintenance tool output signal 93 obtained as a result of processing the input / output data information 90 to the external output interface 913. The external output interface 913 transmits a maintenance tool output signal 94 to the image display device 920, and the image display device 920 displays an image according to the transmitted maintenance tool output signal 94.

  In the control device 200 shown in FIG. 1, the measurement signal database 210, the coal information management database 220, the mill characteristic information database 230, the mill operation calculation information database 240, the calculation result database 250, and the control logic database 260 are included in the control device. Although all or a part of these are arranged inside the control device 200, they can be arranged outside the control device 200.

  The configuration of the coal-fired power plant 100 to which the control device 200 according to the embodiment of the present invention is applied will be described with reference to FIGS. 2 and 3. First, the power generation mechanism of the coal-fired power plant 100 will be briefly described.

  FIG. 2 is a configuration diagram illustrating an outline of the coal-fired power plant 100 to which the control device 200 according to the present embodiment is applied. A boiler 101 constituting the coal-fired power plant 100 includes a plurality of burners 102. The burner 102 supplies the boiler 101 with pulverized coal, which is fuel obtained by finely pulverizing coal with a mill 134, primary air for conveying pulverized coal, and secondary air for combustion adjustment. The pulverized coal supplied by the burner 102 burns inside the boiler 101.

  As shown in FIG. 2, the plurality of burners 102 are divided into a plurality of stages (two stages in FIG. 2) in the vertical direction of the boiler 101 and arranged in one row, and are referred to as a front surface of the boiler 101 (hereinafter referred to as “can front”). ) And the back surface (hereinafter referred to as “after can”). Due to the arrangement of the burner 102, the pulverized coal is burned in the boiler 101 from before and after the can. By improving the combustion balance of the burner 102 before and after the can and in the vertical direction, the combustion efficiency of the pulverized coal can be improved, and more heat can be generated per unit weight of the pulverized coal. .

  Note that the pulverized coal and the primary air are led from the pipe 139 to the secondary air, respectively, from the pipe 141 to the burner 102. The primary air is guided from the fan 120 to the pipe 130 and branched into a pipe 132 that passes through the air heater 104 installed on the downstream side of the boiler 101 and a pipe 131 that bypasses the air heater 104 without passing through the air. Then, the pipes 133 are joined again by the pipe 133 disposed on the downstream side of the air heater 104, and are guided to the mill 134 installed on the upstream side of the burner 102. The primary air passing through the air heater 104 is heated by exchanging heat with the combustion gas flowing down the boiler 101. The heated primary air and the primary air bypassing the air heater 104 convey the differential coal pulverized by the mill 134 to the burner 102.

  The mill 134 is arranged so as to correspond to each stage of the burner 102 before and after the can (four in FIG. 2), and supplies pulverized coal and primary air to the burner 102 constituting each stage. That is, when reducing the coal supply amount, such as when the power generation output is reduced, the mill 134 can be stopped and the burner 102 can be stopped in units of steps. In the mill 134, considering the combustibility of the boiler 101, the mill operation amount including the classifier rotation speed of the mill 134 is adjusted so that pulverized coal having a desired particle size is obtained according to the properties of the coal used. The coal stored in the coal bunker 136 is guided to the coal feeder 135 via the coal conveyor 137, and the supply amount is adjusted by the coal feeder 135. Thereafter, the coal is supplied to the mill 134 via the coal conveyor 138. Details of the structure and characteristics of the mill 134 will be described later.

  Further, the boiler 101 is provided with an after-air port 103 through which air for two-stage combustion is introduced into the boiler 101. The air for two-stage combustion is guided from the pipe 142 to the after air port 103. The air sent to the pipe 140 using the fan 121 is heated by the air heater 104 by heat exchange with the combustion gas, and then branches into a secondary air pipe 141 and an after-air port pipe 142. They are led to the burner 102 and the after-air port 103 of the boiler 101, respectively. The flow rate of the air supplied to the burner 102 and the after-air port 103 can be adjusted by operating air dampers (not shown) installed in the respective pipes 141 and 142.

  The high-temperature combustion gas generated by burning pulverized coal inside the boiler 101 flows downstream along the path inside the boiler 101 and is supplied to the heat exchanger 106 disposed inside the boiler 101. Heat is exchanged to generate steam. Thereafter, the combustion gas becomes exhaust gas and flows into the air heater 104 installed on the downstream side of the boiler 101, and heat exchanged by the air heater 104 heats the air supplied to the boiler 101. And the exhaust gas which passed the air heater 104 is discharged | emitted from the chimney to air | atmosphere after performing the exhaust gas process which is not shown in figure.

  The feed water circulating through the heat exchanger 106 of the boiler 101 is supplied to the heat exchanger 106 via the feed water pump 105 and is heated by the combustion gas flowing down the boiler 101 in the heat exchanger 106 to become high-temperature and high-pressure steam. In this embodiment, the number of heat exchangers is one, but a plurality of heat exchangers may be arranged.

  The high-temperature and high-pressure steam generated in the heat exchanger 106 is guided to the steam turbine 108 through the turbine governor 107 and drives the steam turbine 108 by the energy of the steam. When the steam turbine 108 is driven, the generator 109 generates electricity.

  In the coal-fired power plant 100, various measuring devices for detecting a state quantity indicating the operation state of the coal-fired power plant 100 are arranged.

  A measurement signal 1 of the coal-fired power plant 100 acquired by a measuring instrument disposed in the coal-fired power plant 100 is transmitted to the external input interface 201 of the control device 200 as shown in FIG.

  As a measuring instrument arranged in the coal-fired power plant 100, for example, as shown in FIG. 2, a temperature measuring device 151 that measures the temperature of high-temperature and high-pressure steam supplied from the heat exchanger 106 to the steam turbine 108, the pressure of the steam There are a pressure measuring device 152 that measures the power and a power generation output measuring device 153 that measures the amount of power generated by the power generator 109.

  Feed water generated by cooling the steam by a condenser (not shown) of the steam turbine 108 is supplied to the heat exchanger 106 of the boiler 101 by a feed water pump 105. The flow rate of this water supply is measured by the flow rate measuring device 150.

  A state quantity measurement signal related to the concentration of nitrogen oxide (NOx) contained in the exhaust gas, which is the combustion gas discharged from the boiler 101, is measured by a concentration measuring device 154 provided on the downstream side of the boiler 101.

  FIG. 3 is a diagram illustrating a configuration of a mill included in the coal-fired power plant 100. FIG. 3 shows a mill 134 having a rotary classifier as an example. A table 52 that rotates horizontally by a driving device 51 is disposed in the lower part of the casing 50 of the mill 134. Above the table 52, a roller 57 that can be rotated in the vertical direction by a fluid pressure cylinder 55 via a horizontal shaft 56 is disposed. By pressing the roller 57 against the horizontally rotating table 52 by the fluid pressure cylinder 55, the roller 57 and the table 52 cooperate to pulverize the coal supplied on the table 52.

  An annular body 53 is installed in the casing 50 so as to surround the table 52. The annular body 53 has a structure in which the primary air 54 supplied into the casing 50 from a position below the table 52 can be blown into the upper portion of the casing 50. Connected to the upper portion of the casing 50 is a pulverized coal supply pipe 60 for supplying pulverized coal to the burner 102 (see FIG. 2) of the boiler.

  A rotating chute 58 is installed on the upper portion of the casing 50 so as to be inserted vertically from the outside to the inside of the casing 50. The vertical classifier motor 61 installed above the outside of the casing 50 has an output shaft connected to the rotating chute 58 via a belt. A rotary classifier 62 is mounted on the outer periphery of the rotary chute 58 so as to be positioned at the upper part inside the casing 50. The rotary classifier 62 includes a plurality of rotary blades in the circumferential direction. The rotating chute 58 and the rotary classifier 62 are rotated by the power of the classifier rotating motor 61.

  An inverted conical hopper 63 is installed in the casing 50 so as to be positioned below the rotary classifier 62. The hopper 63 has a slit along the inclined surface so that the coal rising by the primary air 54 can pass through. Above the rotary chute 58, a coal feeder 135 that supplies coal to the rotary chute 58 by driving the coal feeder motor 74 is connected to the rotary chute 58 and installed.

  In the mill 134 shown in FIG. 3, the coal supplied from the coal bunker 136 (see FIG. 2) to the coal feeder 135 is introduced into the casing 50 via the rotating chute 58, falls onto the table 52, and is driven. It is pulverized by the cooperative work of the table 52 and the roller 57 driven by 51. The pulverized coal 59 is conveyed to the primary air 54 and rises, passes through a slit on the hopper 63, enters the hopper 63, and rotates with the rotating chute 58 by driving the classifier motor 61. The machine 62 classifies the coarse particles. Of the classified coal 59, the pulverized coal passes through the rotary classifier 62, is sent to the pulverized coal supply pipe 60, and is supplied to the burner 102 of the boiler 101 (both see FIG. 2). On the other hand, the coarse particles 64 of the classified coal 59 slide down the hopper 63 and are returned to the table 52.

  The primary air 54 supplied to the mill 134 normally has a temperature of about 200 to 240 ° C. to dry the coal, and the mill outlet temperature (air temperature of the pulverized coal supply pipe 60) is set to the set temperature. The temperature is adjusted to hold.

  Various measuring devices such as a measuring device 70 that measures the temperature of the primary air 54 are installed in the mill 134, and measurement information of the mill 134 obtained by these measuring devices is sent to the control device 200. Entered. Examples of such measuring devices include a flow meter 65 that measures the flow rate of the primary air 54 shown in FIG. 3, a rotational speed measuring device 71 that measures the rotational speed of the rotary classifier 62, and a mill from the coal feeder 135. A coal meter 72 that measures the amount of coal supplied to 134, a pressure meter 67 that measures the air pressure of the primary air supply portion in the casing 50, and a pressure meter 66 that measures the primary air pressure in the pulverized coal supply pipe 60. A pressure gauge 68 that measures the pressure oil pressure filled in the fluid pressure cylinder 55, and a measuring instrument 69 that measures the amount of roller shaft lift that occurs when the mill roller 57 crushes coal. The installation location of these measuring devices and the type of measuring device may be changed according to the control logic provided in the control device 200 and the type of control signal to be generated. Regarding the primary air supply portion measured by the pressure gauges 66 and 67 and the air pressure of the pulverized coal supply pipe 60, these differential pressures are input to the control device 200 as measurement signals.

  The control device 200 has a function of determining control signals based on the input measurement information of the mill 134 and outputting them to the actuator (operation end) of each mill. As an example of the control signal, FIG. 3 shows a coal supply command 73, a classifier rotational speed command 75, a primary air flow command 76 for determining a primary air flow rate, and a mill roller pressure oil pressure command 77.

  By the coal supply amount command 73, the number of rotations of the coal supply motor 74 can be changed, and the amount of coal supplied from the coal supply device 135 can be adjusted. With the rotational speed command 75, the rotational speed of the rotary classifier 62 can be adjusted, and the particle size of the pulverized coal passing through the rotary classifier 62 and the pulverized coal supply amount (mill capacity) can be adjusted. In general, increasing the classifier speed reduces the pulverized coal particle size and the mill capacity. The flow rate of the primary air 54 supplied to the mill 134 can be adjusted by the primary air flow rate command 76. By changing the pressure of the pressurized oil filled in the fluid pressure cylinder 55 according to the mill roller pressurized oil pressure command 77, the contact pressure between the table 52 and the roller 57 is adjusted, and a pulverization method corresponding to the coal properties is selected. can do.

  That is, in the control apparatus 200 of the coal-fired power plant 100 according to the present embodiment, the plant measurement signal 1 (see FIG. 1) input via the external input interface 201 includes the coal-fired power plant measured by various measuring instruments. A signal representing at least one of the 100 various state quantities is included. Such state quantities include various measurement information of the mill 134, the flow rates of primary air and secondary air supplied to the boiler 101, the flow rate, temperature, and pressure of feed water supplied to the heat exchanger 106 of the boiler 101. The temperature, pressure and flow rate of the steam generated in the heat exchanger 106 of the boiler 101 and supplied to the steam turbine 108, the temperature of the exhaust gas discharged from the boiler 101, and the environmental load substance contained in the exhaust gas discharged from the boiler 101 Concentration (for example, nitrogen oxide (NOx) concentration, carbon monoxide concentration, etc.), and the exhaust gas flow rate (exhaust gas recirculation flow rate) to be recirculated to the boiler 101 among the exhaust gas discharged from the boiler 101 be able to. The measurement information of the mill 134 includes the speed of the classifier of the mill, the mill roller pressure oil pressure, the mill outlet temperature, the differential pressure between the mill inlet and outlet, the mill roller lift, the amount of coal supplied to the mill, and the like. be able to.

  Moreover, in order to control the coal-fired power plant 100 shown in FIGS. 2 and 3, the coal-fired power plant 100 is generated by the control signal generation unit 500 (see FIG. 1) included in the control device 200 and is connected via the external output interface 202. As the control signal 14 (see FIG. 1) output to, the operation amount at each operation end of the mill 134, the flow rate of air supplied to the boiler 101 via the pipes 133, 141, 142, and air are supplied to the boiler 101. Openings of air dampers installed in the pipes 133, 141, and 142 to adjust the flow rate of air, exhaust gas recirculation flow rate, flow rate of feed water supplied to the heat exchanger 106 through the feed water pump 105, and steam guided to the turbine 108 A signal representing at least one of the opening degree of the turbine governor 107 that determines the flow rate of the turbine governor 107 is included. Examples of the operation amount at each operation end of the mill 134 include the number of revolutions of the classifier of the mill, the pressure of the mill roller pressurized oil, and the amount of coal supplied to the mill.

  FIG. 4 is a flowchart showing a control procedure in the control apparatus 200 of the coal-fired power plant according to the present embodiment shown in FIG. As shown in FIG. 4, the control device 200 executes Steps 1000, 1100, 1200, 1300, 1400, and 1500 in combination. Hereinafter, each step will be described.

  In step 1000, measurement signal data is acquired after the operation of the control device 200 is started. The measurement signal 1 is acquired from the coal-fired power plant 100 via the external input interface 201 and stored in the measurement signal database 210 as the measurement signal 2.

  In step 1100, mill characteristics are calculated for each mill. The mill characteristic evaluation unit 300 uses the measurement data 4 stored in the measurement signal database 210, the coal information 5 stored in the coal information management database 220, and the mill characteristic information 6 stored in the mill characteristic information database 230. The mill characteristic information 7 and the mill operation efficiency information 8 of each mill are calculated with respect to the mill operation condition 9 output by the mill operation calculation unit 400. Among the calculated information, the mill characteristic information 7 is stored in the mill characteristic information database 230, and the mill operation efficiency information 8 is transmitted to the mill operation calculation unit 400. Detailed functions and operations of the mill characteristic evaluation unit 300 will be described later.

  In step 1200, mill operation conditions are calculated. The mill operation calculation unit 400 uses the mill operation efficiency information 8 transmitted from the mill characteristic evaluation unit 300 and the mill operation calculation information data 10 stored in the mill operation calculation information database 240 to optimize the operation conditions of each mill. Find and determine by search method. At that time, each mill is classified into a plurality of groups in consideration of the plant configuration and operation characteristics, and the optimum mill operation conditions for the purpose of increasing the operation efficiency of the entire plant are determined by the interaction between the classified groups. . The determined mill operation condition 11 is stored in the calculation result database 250. Detailed functions and operations of the mill operation calculation unit 400 will be described later.

  In step 1300, a control signal is generated. The control signal generator 500 calculates using the measurement data 3 stored in the measurement signal database 210, the calculation result data 12 stored in the calculation result database 250, and the control logic data 13 stored in the control logic database 260. The control signal 14 is generated.

  In step 1400, the plant is controlled. The control signal 14 generated in step 1300 is output to the coal-fired power plant 100 as the control signal 15 via the external output interface 202, and the plant 100 is controlled to a desired operating state.

  Step 1500 is a branch for determining the end of a series of processing operations. When a signal for ending the operation of the control device 200 is input via the external input device 900, the process proceeds to a step for ending the processing. If the operation of the control device 200 is not terminated, the process returns to step 1000.

  Through the above operation, the control device 200 according to the present embodiment performs a series of processes from acquisition of measurement signal data, calculation of mill characteristics, calculation of mill operation conditions, calculation and generation of control signals, and execution of plant control. Can be automatically acquired and executed.

  Next, operation | movement of the mill characteristic evaluation part 300 of the control apparatus 200 is demonstrated in detail using FIGS.

  FIG. 5 is a configuration diagram illustrating functions of the mill characteristic evaluation unit 300. As shown in FIG. 1, the mill characteristic evaluation unit 300 includes a plurality of mill characteristic evaluation units (A mill characteristic evaluation unit 301a to X mill characteristic evaluation unit 301x). Only the configuration of 301a is shown, and in the following description, the function and operation of the A-mil characteristic evaluation unit 301a will be described. Other functions and operations of the mill characteristic evaluation unit are the same as those of the A mill characteristic evaluation unit 301a.

  As shown in FIG. 5, the A-mill characteristic evaluation unit 301a includes an A-mill basic performance calculation function 302a and an A-mill efficiency calculation function 303a.

  A mill basic performance calculation function 302a includes measurement data 4 stored in measurement signal database 210, coal information 5 stored in coal information management database 220, mill characteristic information 6 stored in mill characteristic information database 230, and mill The A mill basic performance information 304a is calculated using the A mill operation condition 9a input from the operation calculation unit 400, and is output to the A mill efficiency calculation function 303a.

  The A mill efficiency calculation function 303 a calculates A mill operation efficiency 8 a using the A mill basic performance information 304 a, the coal information 5, and the mill characteristic information 6, and transmits it to the mill operation calculation unit 400.

  The A mill basic performance information 304a obtained by the A mill basic performance calculation function 302a and the A mill operation efficiency 8a obtained by the A mill efficiency calculation function 303a are stored in the mill characteristic information database 230 as mill characteristic information 7a.

FIG. 6 is a block diagram showing functions of the A-mill basic performance calculation function 302a shown in FIG. The A mill basic performance calculation function 302a includes function modules F ₁ (x) 310, F ₂ (x) 311, F ₃ (x) 312, F ₄ (x) 313, F ₅ (x) 314, F ₆ (x ) 315, F ₇ (x) 317, F ₈ (x) 318, F ₉ (x) 319, and an arithmetic module 316. Here, x indicates an input item (data information). Input items include primary air flow rate 320, coal feeder flow rate 321, mill outlet temperature 322, default moisture 323, NOx concentration 324, default fuel ratio 325, mill roller lift amount 326, mill roller pressure oil pressure 327, default HGI. (Hardgrove Grindability Index: grindability index) 328, mill differential pressure 329, and mill classifier rotation speed 330 are included.

  Among the input items, the measurement data 4 shown in FIG. 5 corresponds to the mill outlet temperature 322, the NOx concentration 324, the mill roller lift amount 326, and the mill differential pressure 329. Corresponding to the coal information 5 shown in FIG. 5 is a default moisture 323, a default fuel ratio 325, and a default HGI 328. The mill operation condition 9 a shown in FIG. 5 corresponds to the primary air flow rate 320, the coal feeder flow rate 321, the mill roller pressure oil pressure 327, and the mill classifier rotational speed 330. The items constituting the output A mill basic performance information 304a include a C / A value (a value obtained by dividing a mill capacity as a pulverized coal supply amount by a primary air flow rate) 337, a mill capacity 338, and a generated pulverized coal. And a mill power 340 representing power consumed by the classifier motor 61 of the mill.

  The coal information 5 is information registered in the coal information management database 220 with reference to the analysis result of the previous coal composition based on the operation plan. For this reason, the coal information 5 does not necessarily indicate true composition information of the coal actually used. Therefore, the information included in the coal information 5 is written with the word “default”.

  Based on the current plant measurement information, the mill characteristic evaluation unit 300 identifies information such as the composition and particle size of pulverized coal that is pulverized in each mill and supplied to the boiler in real time. Such information can be used for optimum control of the mill.

  Hereinafter, each functional module of the A mill basic performance calculation function 302a will be described with reference to FIGS. 7A, 7B, 8A, 8B, 9, 10, and 11. FIG.

FIG. 7A is a diagram illustrating the function of the functional module F ₁ (x) 310. The functional module F ₁ (x) 310 uses the mill outlet temperature 322 and the default moisture 323 to derive an estimated value 331 of the moisture contained in the coal currently being processed in the mill (Mill A). Specifically, as shown in FIG. 7A, the subtraction operation module 342 calculates a difference 343 between the mill outlet temperature 322 and the mill outlet reference set temperature 341. The mill outlet reference set temperature 341 is preset in the control device 200. Next, the mill exit temperature difference 343 is input to the moisture correction amount calculation module F _1a (x) 344, and the moisture correction amount 345 is output.

FIG. 7B is a diagram illustrating a function characteristic 354 of the moisture correction amount calculation module F _1a (x) 344. As shown in FIG. 7B, F _1a (x) is expressed as a function with respect to the difference 343 in the mill outlet temperature. When the difference 343 of the mill outlet temperature is a positive value (when the mill outlet temperature 322 is higher than the mill outlet reference set temperature 341), the moisture correction amount 345 takes a negative value, and when the difference 343 is a negative value (mill outlet) When the temperature 322 is lower than the mill outlet reference set temperature 341), the moisture correction amount 345 is set to take a positive value.

The function characteristic 354 of the moisture correction amount calculation module F _1a (x) 344 is created based on the mill characteristic information 6 stored in the mill characteristic information database 230 and is limited to a linear function as shown in the figure. Instead, it may be a nonlinear function characteristic.

Returning to FIG. 7A, the description will be continued. Finally, the functional module F ₁ (x) 310 uses the addition operation module 346 to obtain the moisture estimated value 331 by adding the moisture correction amount 345 to the default moisture 323, and outputs this.

FIG. 8A is a diagram illustrating the function of the functional module F ₂ (x) 311. The functional module F ₂ (x) 311 includes a NOx concentration 324, a default fuel ratio 325, a C / A value 337 (previous calculation result), a mill capacity 338 (previous calculation result), an atomization index 339 (previous calculation result), and The fuel ratio estimated value 332 (previous calculation result) is inputted, and the fuel ratio estimated value 332 of coal currently processed in the mill (Mill A) is derived. Here, the “previous calculation result” indicates that each value is a previous calculation result and a value stored in the database (previous value).

A specific method for deriving the estimated coal fuel ratio 332 will be described. As shown in FIG. 8A, the functional module F _2a (x) 347 includes a default fuel ratio 325, a C / A value 337 (previous calculation result), a mill capacity 338 (previous calculation result), and an atomization index 339 (previous calculation result). ) And the fuel ratio estimated value 332 (previous calculation result), the standard NOx concentration 348 estimated from the latest mill characteristic information and coal information is obtained and output. For the functional module F _2a (x) 347, a model obtained by learning a database of input / output item information included in the mill characteristic information 6 using a statistical method such as multiple regression analysis or a neural network can be used.

Next, the functional module F _2a (x) 347 calculates a difference 350 between the NOx concentration 324 and the standard NOx concentration 348 by the subtraction operation module 349. The standard NOx concentration 348 is set in the control device 200 in advance. Next, the NOx concentration difference 350 is input to the fuel ratio correction module F _2b (x) 351, and the fuel ratio correction amount 352 is output.

FIG. 8B is a diagram illustrating a function characteristic 355 of the fuel ratio correction module F _2b (x) 351. As shown in FIG. 8B, the fuel ratio correction module F _2b (x) 351 is expressed as a function with respect to the NOx concentration difference 350. When the NOx concentration difference 350 is a positive value (when the NOx concentration 324 is higher than the standard NOx concentration 348), the fuel ratio correction amount 352 takes a positive value, and when the difference 350 is a negative value (the NOx concentration 324 is standard). When the NOx concentration is lower than 348), the fuel ratio correction amount 352 is set to take a negative value.

The function characteristic 355 of the fuel ratio correction module F _2b (x) 351 is based on the mill characteristic information 6 stored in the mill characteristic information database 230 in the same manner as the function characteristic 354 of the moisture correction amount calculation module F _1a (x) 344. And is not limited to a linear function.

Returning to FIG. 8A, the description will be continued. Finally, the functional module F ₂ (x) 311 uses the addition operation module 353 to obtain the fuel ratio estimated value 332 by adding the fuel ratio correction amount 352 to the fuel ratio estimated value 332 (previous calculation result). And output this.

FIG. 9 is a diagram illustrating functions of the functional module F ₃ (x) 312. The function module F ₃ (x) 312 inputs the primary air flow rate 320, the coal feeder flow rate 321, the mill roller lift amount 326, the mill roller pressure oil pressure 327, and the HGI estimated value 333 (previous calculation result), and the reference The mill roller lift amount 334 is obtained and output.

Specifically, as shown in FIG. 9, the functional module F ₃ (x) 312 first has a primary air flow rate 320, a coal feeder flow rate 321, a mill roller pressurization oil pressure 327, and their respective amounts. A reference primary air flow rate 356, a reference coal feeder flow rate 359, and a reference mill roller pressure oil pressure 362, which are measured amounts under standard operating conditions, are input. A subtraction operation module 357 calculates a primary air flow rate difference 358 that is a difference between the primary air flow rate 320 and the reference primary air flow rate 356. The subtraction operation module 360 calculates a difference 361 in the coal feeder flow rate that is the difference between the coal feeder flow rate 321 and the reference coal feeder flow rate 359. The subtraction operation module 363 calculates a difference 364 in the mill roller pressure oil pressure that is the difference between the mill roller pressure oil pressure 327 and the reference mill roller pressure oil pressure 362. The reference primary air flow rate 356, the reference coal feeder flow rate 359, and the reference mill roller pressure oil pressure 362 are determined in advance and set in the control device 200.

Next, the obtained difference and the estimated HGI value 333 (previous calculation result) are input to the function module F _3a (x) 365 to obtain a mill roller lift amount correction amount 366. In the functional module F _3a (x) 365, as in the functional module F _2a (x) 347, the input / output item information database included in the mill characteristic information 6 is obtained using a statistical method such as multiple regression analysis or neural network. A learned model can be used.

Finally, the functional module F ₃ (x) 312 obtains the reference mill roller lift amount 334 by adding the calculated mill roller lift amount correction amount 366 to the mill roller lift amount 326 using the addition operation module 367. And output this.

FIG. 10 is a diagram illustrating the function of the function module F ₄ (x) 313. The function module F ₄ (x) 313 inputs the primary air flow rate 320, the coal feeder flow rate 321, the default HGI 328, the mill differential pressure 329, the mill classifier rotation speed 330, and the HGI estimated value 333 (previous calculation result). The reference mill differential pressure 335 is obtained and output.

Specifically, as shown in FIG. 10, the functional module F ₄ (x) 313 first has a primary air flow rate 320, a coal feeder flow rate 321, and a mill classifier rotational speed 330, and their respective amounts. A reference primary air flow rate 356, a reference coal feeder flow rate 359, and a reference mill classifier rotation speed 368, which are measured quantities under standard operating conditions, are input. And the difference of these quantity is calculated | required by the subtraction calculation modules 357, 360, and 369, respectively, and the difference 358 of a primary air flow rate, the difference 361 of a coal feeder flow rate, and the difference 370 of a mill classifier rotation speed are calculated, respectively. . The reference mill classifier rotation speed 368 is set in the control device 200 in advance.

Next, each obtained difference and the HGI estimated value 333 (previous calculation result) are input to the functional module F _4a (x) 371 to obtain a mill differential pressure correction amount 372. Similarly to the function module F _2a (x) 347 and the function module F _3a (x) 365, the function module F _4a (x) 371 includes a multiple regression analysis of the input / output item information database included in the mill characteristic information 6 A model trained using a statistical method such as a neural network can be used.

Finally, the functional module F ₄ (x) 313 obtains the reference mil differential pressure 335 by adding the obtained mil differential pressure correction amount 372 to the mil differential pressure 329 using the addition operation module 373, and calculates this. Output.

The reference mill roller lift amount 334 and the reference mill differential pressure 335 obtained by the function modules F ₃ (x) 312 and F ₄ (x) 313 are obtained when the HGI estimated value is obtained in the function module F ₅ (x) described later. This is the mill state quantity when the influence of noise (noise caused by the current mill operating conditions) included in the measured values of mill roller lift and mill differential pressure, which are input items, is excluded and based on standard operating conditions. . The reference mill roller lift amount 334 and the reference mill differential pressure 335 bring about an effect of improving the estimation accuracy of HGI.

  Returning to FIG. 6, the description will be continued.

The functional module F ₅ (x) 314 includes a moisture estimation value 331 and a fuel ratio obtained by the functional modules F ₁ (x) 310, F ₂ (x) 311, F ₃ (x) 312, and F ₄ (x) 313. The estimated value 332, the reference mill roller lift amount 334, and the reference mill differential pressure 335 are input, and the HGI estimated value 333 is output. Similarly to F _2a (x) 347, F _3a (x) 365, and F _4a (x) 371, the function module F ₅ (x) 314 has a database of input / output item information included in the mill characteristic information 6. A model trained using a statistical method such as multiple regression analysis or neural network can be used. Further, it is a well-known knowledge that the estimated moisture value 331, estimated fuel ratio 332, reference mill roller lift amount 334, and reference mill differential pressure 335 are qualitatively correlated with the HGI characteristics of coal. HGI can be estimated with high accuracy. The HGI estimated value 333 is stored in the mill characteristic information database 230.

The functional module F ₆ (x) 315 inputs the mill roller pressure oil pressure 327, the mill classifier rotation speed 330, and the HGI estimated value 333, and outputs a coal output rate 336. The coal output rate is an index indicating the ratio of the amount of pulverized coal supplied from the mill to the boiler with respect to the amount of coal supplied from the coal feeder to the mill. The coal output rate 336 is determined from the correlation among the mill roller pressure oil pressure 327, the mill classifier rotation speed 330, and the HGI estimated value 333 because it affects the ease of coal crushing and mill crushing / classifying conditions. Similarly to the function module F ₅ (x) 314, the function module F ₆ (x) 315 preferably uses a statistical model.

The function module F ₆ (x) 315 uses the multiplication operation module 316 to obtain a mill coal output (mill capacity) 338 by multiplying the calculated coal output rate 336 by the coal feeder flow rate 321, This is output to the mill efficiency calculation function 303a (see FIG. 5).

The functional module F ₉ (x) 319 receives the primary air flow rate 320 and the mill capacity 338, calculates the C / A value 337, and outputs this to the A mill efficiency calculation function 303a (see FIG. 5). F ₉ (x) 319 calculates the C / A value 337 by dividing the mill capacity 338 by the primary air flow rate 320.

The function module F ₇ (x) 317 inputs the mill roller pressure oil pressure 327, the mill classifier rotation speed 330, and the HGI estimated value 333, calculates the atomization index 339, and calculates the A mill efficiency calculation function 303a ( (See FIG. 5). The atomization index 339 is an index that quantitatively indicates the particle size of the pulverized coal pulverized by the mill, and normally, a 200 mesh pass value (the ratio of the pulverized coal that has passed through the 75 μ-interval sieve) is used. The larger the 200 mesh pass value, the smaller the particle size, and the higher the combustion efficiency in the boiler. As with the coal output rate 336, the atomization index 339 also affects the ease of coal crushing and mill crushing / classifying conditions. Therefore, the mill roller pressure oil pressure 327, the mill classifier rotation speed 330, and the HGI estimated value 333 are affected. From the correlation of It is desirable that the functional module F ₇ (x) 317 also uses a model based on a statistical method.

The function module F ₈ (x) 318 obtains the mill power 340 with respect to the mill classifier rotational speed 330 and outputs this to the A mill efficiency calculation function 303a (see FIG. 5). The mill power 340 has a first-order correlation with the mill classifier rotational speed 330.

FIG. 11 is a diagram illustrating the function characteristic 374 of the functional module F ₈ (x) 318. As shown in FIG. 11, the function characteristic 374 of F ₈ (x) 318 is given by a linear function of the mill classifier rotational speed 330 and the mill power 340. The function characteristic 374 is created based on the mill characteristic information 6 stored in the mill characteristic information database 230.

  This is the end of the detailed description of the function of the A-mill basic performance calculation function 302a.

FIG. 12 is a block diagram showing the function of the A-mill efficiency calculation function 303a shown in FIG. The A-mill efficiency calculation function 303a includes functional modules F ₁₀ (x) 375, F ₁₁ (x) 377, and F ₁₂ (x) 379.

The function module F ₁₀ (x) 375 inputs the C / A value 337, the mill capacity 338, and the atomization index 339 that are input as the calculation results of the A mill basic performance calculation function 302a, and obtains the estimated combustion rate 376. Output. The estimated combustion rate 376 is an estimated value of the ratio of the amount of pulverized coal that is completely burned when pulverized coal is burned in the burner portion of the boiler with respect to the amount of pulverized coal supplied from the mill A to the boiler.

  The estimated combustion rate 376 is determined by the C / A value 337, the atomization index 339, and the mill capacity 338 when the burner structure and the combustion conditions are constant. Specifically, a relationship between the C / A value 337, the atomization index 339, and the mill capacity 338 and the combustion rate is obtained by a characteristic evaluation test performed in advance, and this is stored in the mill characteristic information database 230. deep. Then, by constructing a model for estimating the combustion rate using this data by a statistical method such as multiple regression analysis or a neural network, it is possible to estimate the combustion rate for an arbitrary input condition.

The functional module F ₁₁ (x) 377 calculates the plant combustion efficiency 378 using the combustion rate estimation value 376 calculated by the functional module F ₁₀ (x) 375 and the coal information 5 stored in the coal information management database 220. To do. The plant combustion efficiency 378 is the combustion efficiency of pulverized coal in the coal-fired power plant 100, and can be obtained for each mill. Assuming that the plant combustion efficiency 378 of the mill A is η ^c _A [%], η ^c _A is calculated by the following equation (1).

Here, α _A [%] is the combustion rate estimated value of the mill A, [C] [%] is the carbon content ratio in the operational carbon composition, ^{Q C} is higher heating value per unit mass of carbon component (= 3.38 × 10 ⁴ [kJ / kg]) and Q ^coal _A [kJ / kg] are the higher heating values per unit mass of the operating coal. [C] and Q ^coal _A are analysis information of the coal composition and are included in the coal information 5. In Formula (1), η ^c _A , which is the plant combustion efficiency 378, is included in the pulverized coal that burns completely with respect to the higher calorific value of the coal supplied from the mill A to the boiler (= thermal energy input to the boiler). It means that it is the ratio of the higher calorific value (= heat energy generated by combustion) corresponding to the carbon content. The larger the value of η ^c _A is, the more efficiently energy is generated by combustion.

The function module F ₁₂ (x) 379 uses the plant combustion efficiency 378, the mill capacity 339, and the mill power 340 calculated by the function module F ₁₁ (x) 377, and the A mill operation efficiency 8a that is the operation efficiency of the mill A. Is output to the mill operation calculation unit 400 (see FIG. 1). Here, when the A mill operation efficiency 8a is η ^m _A [%], η ^m _A is calculated by the following equations (2) and (3).

Here, P ^M _A [kW] is the mill power 340 of the mill A, P ^G _A [kW] is an estimated value of the power generation output of the plant for the fuel supplied from the mill A, and G _A [kg / s] is the mill capacity. 339, η ^g [%] is the power generation end efficiency of the plant. η ^g is a constant determined by the plant equipment configuration and operation method. Equation (2) means that the mill operation efficiency η ^m _A is a value obtained by subtracting the efficiency corresponding to the mill power P ^M _A from the plant combustion efficiency η ^c _A.

  From the above description, the mill operation efficiency information 8 output by the mill characteristic evaluation unit 300 is calculated from mill measurement information, operating coal information, mill characteristic information, and combustion efficiency based on mill operation conditions and mill power. It is a performance value and can be considered as the contribution of each mill to the operating efficiency of the entire plant.

  FIG. 13 is a flowchart showing an operation procedure of mill characteristic evaluation unit 300 based on the above description. The flowchart shown in FIG. 13 shows the operation in step 1100 of the flowchart showing the control of the control device 200 shown in FIG. 4 in detail, and includes steps 1110 to 1123. Mill characteristic evaluation unit 300 executes steps 1110 to 1123 in combination. Hereinafter, each step will be described.

  In step 1110, the counter i is initialized to 1 after the operation of the mill characteristic evaluation unit 300 is started. The counter i is a subscript representing the number of each mill. In this flowchart, each mill is managed by a number, and the number of the mill is counted as a subscript i when the flowchart is executed.

In step 1111, the functional module F ₁ (x) 310 is operated to calculate an estimated value 331 of moisture contained in the operational coal of the mill i (coal currently processed in the mill i).

In step 1112, the function module F ₂ (x) 311 is operated to calculate the estimated fuel ratio 332 of the operating coal of the mill i.

In step 1113, the function module F ₃ (x) 312 is operated to calculate the reference mill roller lift amount 334 of the mill i.

In step 1114, the function module F ₄ (x) 313 is operated to calculate the reference mill differential pressure 335 of the mill i.

In step 1115, the function module F ₅ (x) 314 is operated to calculate the HGI estimated value 333 of the mill i.

In step 1116, the function module F ₆ (x) 315 and the multiplication operation module 316 are operated, and the mill capacity 338 of the mill i is calculated and estimated.

In step 1117, the functional module F ₉ (x) 319 is operated, and the C / A value 337 of the mill i is calculated.

In step 1118, the functional module F ₇ (x) 317 is operated, and the atomization index 339 of the mill i is calculated and estimated.

In step 1119, the function module F ₈ (x) 318 is operated, and the mill power 340 of the mill i is calculated.

In step 1120, the functional module F ₁₀ (x) 375 is operated, and the combustion rate 376 of the mill i is calculated and estimated.

In step 1121, the function module F ₁₁ (x) 377 is operated, and the plant combustion efficiency 378 of the mill i is calculated.

In step 1122, the functional module F ₁₂ (x) 379 is operated, and the operation efficiency 8 of the mill i is calculated.

  Step 1123 is a branch for determining the counter i. If the counter i does not match the number of operating mills (the number of operating mills), 1 is added to i and the process returns to step 1111. When the counter i matches the number of operating mills, the process proceeds to a step of terminating the operation of the mill characteristic evaluation unit 300.

  As is clear from the above description, the mill characteristic evaluation unit 300, based on the coal measurement data obtained from the plant measurement data and the previous analysis results, the operating coal properties (moisture, fuel ratio, and HGI) and the mill Properties (C / A value, mill capacity, atomization index, mill power, and mill operation efficiency) are estimated in real time. Since the mill characteristic evaluation unit 300 according to the present embodiment can reflect the current operation state of the plant, the mill characteristic evaluation unit 300 can provide more accurate mill characteristics than the case where only the coal information analyzed in advance is used. Estimation is possible.

  Above, detailed description of operation | movement of the mill characteristic evaluation part 300 of the control apparatus 200 is complete | finished.

  Next, operation | movement of the mill operation calculation part 400 of the control apparatus 200 is demonstrated in detail using FIG.14 and FIG.15.

  FIG. 14 is a flowchart showing an operation procedure of the mill operation calculation unit 400. The flowchart shown in FIG. 14 shows in detail the operation in step 1200 of the flowchart showing the control of the control device 200 shown in FIG. 4, and steps 1210 to 1218 are executed in combination. Hereinafter, each step will be described.

  In step 1210, after the operation of the mill operation calculation unit 400 is started, a mill group is set. That is, the mills are classified into a plurality of groups (mill groups) based on the plant configuration and operation conditions. Here, grouping of the mill will be described with reference to FIG.

  FIG. 15 is a schematic diagram showing grouping of mills, and displays a boiler and a burner. In FIG. 15, the figure which looked at the opposed combustion type boiler which is an example of a typical coal combustion boiler from the side is shown. The boiler is equipped with a total of 6 burners, 3 stages before and after the can. As shown in FIG. 15, each of the six mills A to F corresponds to each burner and can supply pulverized coal.

  Such burner arrangement information is displayed on the image display device 920. The operator of the coal-fired power plant 100 performs grouping of mills by combining mills in units of burner stages or by combining mills before and after the cans while viewing the burner arrangement information. In FIG. 15, as an example of grouping, mill A and mill D are group 1, mill B, mill C, mill E, and mill F are group 2, mill A, mill B, and mill C are group 3, and mill D. , Mill E, and Mill F are classified as Group 4. Further, although detailed reasons will be described later, it is desirable to perform the grouping in consideration of the balance of the combustion efficiency inside the boiler furnace.

  Returning to FIG. 14, the description will be continued. In step 1211, for each mill group set in step 1210, parameters used when searching for mill operation conditions are initialized. This parameter will be described later.

  In step 1212, a counter n, which is the number of repetitions in the search for mill operation conditions, is initialized to 1.

  In step 1213, the counter j is initialized to 1. The counter j is a subscript representing the number of each mill group. In this flowchart, each mill group is managed with a number, and the number of each mill group is counted as a subscript j when the flowchart is executed.

In step 1214, an evaluation function value E _j (x _j ) given by the following formula (4), formula (5), and formula (6) is calculated for the mill group j. Here, x _j is a set (vector) of operation conditions of the mills belonging to the mill group j. As described above, the primary air flow rate, the coal feeder flow rate, the mill roller pressurizing oil pressure, and the mill classification of each mill. Includes machine speed.

In the equation (4), the first term (η ^g _j ) on the right side represents the average mill operation efficiency of the mill group j, and the second term represents the mill group j and all other mill groups k (k ≠ j). Represents the effect of the driving efficiency balance. In a coal boiler, there is a combustion balance between burners as a factor affecting the combustion state in the furnace. In most cases, the boiler is designed such that when coal is burned from each burner evenly, the combustion state in the furnace is the best, and the operating efficiency of the entire plant is maximized. Therefore, it is necessary not only to maximize the operation efficiency of a single mill, but also to determine the operation conditions of the mill so as to optimize the balance of operation efficiency between mills in consideration of the arrangement of burners.

The second term on the right side of Equation (4) is the sum of squares of the differences with respect to the equal balance (operation efficiency ratio = 1) of the operation efficiency ratios of the other mill group k (k ≠ j) and mill group j. The worse the balance of operating efficiency with the group, the larger the calculated value. Therefore, the operation efficiency of the entire plant can be maximized by an optimum search method in which E _j (x _j ) obtained by Expression (4) is used as an evaluation function and the value of this evaluation function is maximized.

Here, C _jk in equation (4) is a coefficient that determines a combination of mill groups (subscripts j, k) that takes into account the influence of the balance of operating efficiency, and as shown in equation (6), the determination flag θ _jk If 1 is true (= true), 1 is taken, and if it is false (= false), 0 is taken. θ _jk is arbitrarily set in step 1211. In addition, regarding the meanings of the variables and subscripts in Expression (4), Expression (5), and Expression (6), k is a counter of another mill group, J is the number of groups, l is a counter of the mill, and Lj is a group. This represents the number of mills belonging to j. The determination flag θ _jk is included in the mill operation calculation information data 10 stored in the mill operation calculation information database 240 as described above.

In step 1215, the operation condition of the mill group j is obtained using the optimum search method. Specifically, a combination of mill operation conditions x _j belonging to the mill group j that maximizes the evaluation function value E _j (x _j ) calculated in step 1214 is searched. As the search algorithm, any known method such as gradient method, random search, genetic algorithm, annealing method, tabu search, and particle swarm optimization can be used. Parameters necessary for operating the search algorithm are included in the mill operation calculation information data 10 stored in the mill operation calculation information database 240 as described above.

  Step 1216 is a branch for determining the counter j. If the counter j does not match the number of mill groups, 1 is added to j and the process returns to step 1214. If the counter j matches the number of mill groups, the process proceeds to the next step 1217.

  Step 1217 is a branch for determining the counter n. If the counter n does not match the maximum number of iterations of the search algorithm, 1 is added to n, and the process returns to step 1213. If the counter n matches the maximum number of iterations, the process proceeds to the next step 1218. The maximum number of iterations is set in advance before executing this flowchart.

  In step 1218, the calculation result in this flowchart is stored in the calculation result database 250, and the operation proceeds to the step of ending the operation of the mill operation calculation unit 400.

As is clear from the above description, the mill operation calculation unit 400 uses the evaluation function E _j (x _j ) obtained by the equations (4), (5), and (6) to operate the mill alone. In addition to maximizing efficiency, mill operation conditions are determined so as to optimize the balance of operation efficiency between mills in consideration of the arrangement of burners. As a result, the operation efficiency of the entire plant can be maximized.

  Above, detailed description of operation | movement of the mill operation calculation part 400 of the control apparatus 200 is complete | finished.

  Next, screens displayed on the image display device 920 (see FIG. 1) connected to the control device 200 of the coal-fired power plant according to the present embodiment will be described with reference to FIGS. The image display device 920 is connected to a maintenance tool 910 that transmits / receives data to / from the control device 200, and displays an image according to the maintenance tool output signal 94 transmitted from the external output interface 913 of the maintenance tool 910.

  The operator of the coal-fired power plant 100 operates the mouse 902 of the external input device 900 in a state where the screen shown in FIG. 16, FIG. 17, or FIG. 18 is displayed on the image display device 920, and checks the check box on the screen. Click to select a check box (display a check). Further, by operating the mouse 902 and clicking a button on the screen, the button can be selected (pressed). Further, the user can operate the mouse 902 to move the focus to a numerical box on the screen and use the keyboard 901 to input numerical values.

  FIG. 16 is an example of a mill group setting screen displayed on the image display device 920 when the mill operation calculation unit 400 is executed in the coal-fired power plant control apparatus 200 according to the present embodiment. This screen is displayed corresponding to steps 1210 and 1211 in the flowchart of FIG.

  In the screen shown in FIG. 16, a mill-burner arrangement diagram 3000 and a mill group list 3005 are displayed, and mill group setting in step 1210 and initialization of mill group parameters in step 1211 can be performed. In the mill-burner arrangement diagram 3000, each mill is displayed in association with the burner arrangement.

  Mill-burner arrangement on the screen 3000 By selecting a check box 3001 corresponding to each burner shown in FIG. 3000 by operating the mouse 902, mills to be grouped can be selected. Mill-Burner Arrangement As shown in FIG. 3000, since the actual arrangement of the burners can be referred to, grouping considering the operational efficiency balance between the burners is possible.

  After selecting mills to be grouped, by selecting an add group button 3002, a mill group based on the selected mill can be newly added to the mill group list 3005. Further, after selecting an arbitrary group with the check box 3006 for an existing mill group in the mill group list 3005, the selected mill group can be deleted from the list 3005 by selecting a group delete button 3003. it can.

The mill group list 3005 includes a group No. for each added mill group. (Group number) 3007, names 3008 of mills belonging to the group, and a check box 3009 for selecting whether or not to consider the influence of the operational efficiency balance between the groups exist. Here, selection or non-selection of the check box 3009 corresponds to true or false of the determination flag θ _jk in Expression (6). That is, when the check box 3009 is checked by operating the mouse 902, θ _jk is initialized to true (= true), and when the check box is removed, θ _jk is initialized to false (= false).

  After the above input is completed, by selecting a group update button 3004, the set mill group information can be updated.

  After all the mill groups have been set, by selecting an end button 3010, the mill group setting screen can be ended, and mill grouping and parameter settings for the mill group can be ended.

  FIG. 17 shows a mill evaluation value displayed on the image display device 920 when confirming a trend of mill characteristic information obtained by executing the mill characteristic evaluation unit 300 in the control apparatus 200 of the coal-fired power plant according to the present embodiment. It is an example of the display screen of a trend.

  On the screen shown in FIG. 17, a mill-burner layout diagram 3100 and a graph drawing area 3104 are displayed. The graph drawing area 3104 displays a time series trend graph 3105 of the mill characteristic information 7 obtained by the mill characteristic evaluation unit 300 for any mill included in the coal-fired power plant 100.

  Mill-burner arrangement on the screen Select a mill for which the trend graph 3105 is to be displayed by checking the check box 3101 corresponding to each stage of the burner shown in FIG. 3100 by operating the mouse 902. Can do. A plurality of mills can be selected, and a trend graph 3105 of mill characteristic values is displayed in the graph drawing area 3104 by the number of selected mills. In the example of FIG. 17, a trend graph 3105 for mill A and mill D is displayed.

  Further, when a pull-down button 3102 provided on the right side of the screen is selected with the mouse 902, a pull-down menu 3103 is displayed and it is desired to be displayed in the graph area 3104 from various mill characteristic information 7 obtained by the mill characteristic evaluation unit 300. One item can be selected.

  Further, by selecting the end button 3106, the display screen of the mill evaluation value trend can be ended, and the display of the trend graph of the mill characteristic information 7 can be ended.

  As described above, the operator of the plant 100 can grasp the characteristic information 7 of each mill in real time from the screen shown in FIG. That is, regardless of the operation of the control device 200, it is possible to grasp a rapid change in the operation state of the mill that is difficult to determine from the existing measurement information, which can contribute to preventive maintenance of the mill.

FIG. 18 shows the trend of the average operating efficiency (average mill operating efficiency η ^g _j ) of each mill group obtained by executing the mill operation calculation unit 400 in the coal-fired power plant control apparatus 200 according to this embodiment, and the overall plant. It is an example of a display screen of a trend of operational efficiency balance / plant efficiency displayed on the image display device 920 when confirming a trend of operational efficiency. As shown in FIG. 18, in the upper half of this screen, a trend graph of average operation efficiency (group operation efficiency) of each mill group is displayed as an operation efficiency balance trend. In the lower half of the screen, a trend graph of the operation efficiency (plant efficiency) of the entire plant is displayed as a plant efficiency trend.

  In the graph of the operation efficiency balance trend, the trend graph of the operation efficiency of the two types of groups selected based on the setting of the operation efficiency balance between the groups set on the mill group setting screen of FIG. 16 is displayed. First, a combination of mill groups is determined by selecting pull-down menus 3203 and 3204 with the mouse 902. At this time, mill groups that can be selected from the pull-down menus 3203 and 3204 are only combinations of groups for which the check boxes 3009 are selected in FIG. When the combination of mill groups is determined, trend graphs 3201 and 3202 of the average operating efficiency of the two selected mill groups are displayed in the graph area 3200.

  In the plant efficiency trend graph, a trend graph of the operation efficiency of the entire plant is displayed. In the graph area 3205, a trend graph 3206 of plant operation efficiency calculated in real time based on the measurement information is displayed. Here, the plant operation efficiency is not calculated from the mill operation efficiency derived by the mill efficiency calculation function of the mill characteristic evaluation unit 300, but is calculated based on measurement information measured as a result of actual plant operation. This measurement information includes at least one information among the exhaust gas flow rate, the exhaust gas temperature, the unburned ash content, the carbon monoxide concentration, the heat exchanger metal temperature, and the exhaust gas composition.

  Further, on the display screen for the trend of operational efficiency balance / plant efficiency shown in FIG. 18, a target value of plant efficiency can be set and displayed in the graph area 3205. By inputting the target value of plant efficiency in the numerical value box 3208 and selecting the setting button 3209, the target value 3207 of plant efficiency is additionally displayed in the graph area 3205.

  Further, by selecting the end button 3210, the operation efficiency balance / plant efficiency trend display screen can be ended, and the display of the operation efficiency balance trend and the plant efficiency trend can be ended.

  As described above, from the operation efficiency balance / plant efficiency trend display screen shown in FIG. 18, the plant operator is in a state where the balance between the set operation efficiency is desirable (average operation efficiency ratio = 1). It is possible to check in real time whether the control is performed so that It is also possible to confirm in real time whether the plant operating efficiency has achieved the set target value.

  Above, description about the screen displayed on the image display apparatus 920 connected to the control apparatus 200 of the coal-fired power plant by a present Example is complete | finished.

  In addition, this invention is not limited to said Example, Various modifications are included. For example, the above-described embodiments are described in detail for easy understanding of the present invention, and the present invention is not necessarily limited to an aspect including all the configurations described.

  Each configuration of the control device according to the present invention may be realized by hardware, for example, by designing a part or all of them with an integrated circuit. Some or all of these may be realized by software so that the processor interprets and executes a program that realizes each function. Information such as programs, tables, files, measurement information, and calculation information for realizing each function is stored in a recording device such as a memory, a hard disk, and an SSD (Solid State Drive), or an IC card, an SD card, and a DVD. It can be recorded on a recording medium. Therefore, each function of the control device according to the present invention can be realized as a processing unit, a processing unit, a program module, and the like.

  Further, in each drawing, control lines and information lines are described as necessary for explanation, and not all control lines and information lines necessary as products are necessarily described. In an actual product, it may be considered that almost all components are connected to each other.

  Above, detailed description of the control apparatus of the coal-fired power plant by this invention is complete | finished.

  DESCRIPTION OF SYMBOLS 1 ... Measurement signal, 3 ... Measurement data, 4 ... Measurement data, 5 ... Coal information, 6 ... Mill characteristic information, 7 ... Mill characteristic information, 8 ... Mill operation efficiency information, 9 ... Mill operation conditions, 10 ... Mill operation calculation Information data 11 ... Mill operation conditions, 12 ... Calculation result data, 13 ... Control logic data, 14 ... Control signal, 90 ... Input / output data information, 91 ... Maintenance tool input signal, 92 ... Maintenance tool input signal, 93 ... Maintenance Tool output signal, 94 ... Maintenance tool output signal, 100 ... Coal-fired power plant, 101 ... Boiler, 102 ... Burner, 134 ... Mill, 200 ... Control device, 201 ... External input interface, 202 ... External output interface, 210 ... Measurement signal Database 220 ... Coal information management database 230 ... Mill characteristic information database 240 ... Mill operation calculation information database 250, calculation result database, 260, control logic database, 300, mill characteristic evaluation unit, 301a, A mill characteristic evaluation unit, 302a, A mill basic performance calculation function, 303a, A mill efficiency calculation function, 304a, A mill Basic performance information, 400 ... mill operation calculation unit, 500 ... control signal generation unit, 800 ... input / output unit, 900 ... external input device, 901 ... keyboard, 902 ... mouse, 910 ... maintenance tool, 911 ... external input interface, 912 Data transmission / reception processing unit 913 External output interface 920 Image display device

Claims (17)

From a coal-fired power plant comprising a mill that pulverizes coal into pulverized coal and a boiler that burns pulverized coal, a measurement signal representing a state quantity of the coal-fired power plant is acquired, and the coal-fired power plant is obtained using the measurement signal. In the control device of a coal-fired power plant that controls
Using the measurement signal, a control signal generation unit that generates a control signal to be given to the coal-fired power plant,
A measurement signal database for storing data included in the measurement signal;
A coal information management database for storing information on the coal;
Mill characteristic information database for storing information on the characteristics of the mill,
Using the information stored in the measurement signal database, the coal information management database, and the mill characteristic information database, a mill characteristic evaluation unit that calculates the characteristics of the mill,
Using the mill characteristics calculated by the mill characteristic evaluation unit, a mill operation calculation unit that calculates operating conditions of the mill,
A calculation result database for storing the operation conditions of the mill calculated by the mill operation calculation unit;
A control logic database for storing control logic for the coal-fired power plant, and
The coal information management database stores at least the moisture value of the coal, the fuel ratio, and the HGI that is a pulverization index as information on the coal,
The control signal generation unit is configured to generate the control signal using information stored in the calculation result database and the control logic database.
A control apparatus for a coal-fired power plant. In the control apparatus of the coal-fired power plant according to claim 1,
The measurement signal is supplied to the mill classifier rotation speed, the roller pressure pressure of the mill, the outlet temperature of the mill, the pressure difference between the inlet and outlet of the mill, the roller lift of the mill, and the mill. Coal supply amount, flow rates of primary air and secondary air supplied to the boiler, feed water flow rate of the boiler, feed water temperature of the boiler, feed water pressure of the boiler, steam temperature of the boiler, steam pressure of the boiler A signal representing at least one of the steam flow rate of the boiler, the exhaust gas temperature of the boiler, the concentration of environmentally hazardous substances contained in the exhaust gas of the boiler, and the exhaust gas recirculation flow rate of the boiler,
The control signal includes the speed of rotation of the classifier of the mill, the roller pressurizing oil pressure of the mill, the amount of coal supplied to the mill, the air flow rate of the boiler, the air damper opening of the boiler, and the exhaust gas recirculation of the boiler. A control device for a coal-fired power plant including a signal that determines at least one of a flow rate, a feed water flow rate of the boiler, and a turbine governor opening. In the control apparatus of the coal-fired power plant according to claim 1,
The mill characteristic evaluation unit has a mill basic performance calculation function and a mill efficiency calculation function,
Mill basic performance calculation function
Input the information stored in the measurement signal database, the coal information management database, and the mill characteristic information database,
The mill capacity which is the supply amount of pulverized coal supplied to the boiler by the mill, the C / A value obtained by dividing the mill capacity by the primary air flow rate, the atomization index indicating the degree of atomization of the pulverized coal, and the mill Calculate the basic mill performance information including the mill power, which is the power consumed in
This mill basic performance information is stored in the mill characteristic information database as information regarding the characteristics of the mill,
The mill efficiency calculation function is
A control device for a coal-fired power plant that calculates the operation efficiency of the mill based on the basic mill performance information. In the control apparatus of the coal-fired power plant according to claim 3,
The mill basic performance calculation function is
Input the outlet temperature of the mill stored in the measurement signal database and the moisture value of the coal stored in the coal information management database,
A difference between the mill outlet temperature and a predetermined reference set temperature is obtained, and when the difference takes a negative value, the moisture correction amount is set as a positive value.When the difference takes a positive value, the moisture correction amount is set as a negative value. Perform the operation to
A control device for a coal-fired power plant that estimates the moisture value of coal being processed in the mill by adding the moisture correction amount to the moisture value of the coal to obtain an estimated moisture value. In the control apparatus of the coal-fired power plant according to claim 3,
The mill basic performance calculation function is
Calculate the standard NOx concentration from the mill capacity, C / A value and atomization index stored in the mill characteristic information database, and the fuel ratio and estimated fuel ratio of coal stored in the coal information management database;
The difference between the standard NOx concentration and the NOx concentration contained in the measurement signal is obtained. If this difference takes a negative value, the fuel ratio correction amount is set to a negative value. If the difference takes a positive value, the fuel ratio correction amount Perform a calculation with a positive value,
A control apparatus for a coal-fired power plant that estimates a fuel ratio of coal being processed in the mill by adding the fuel ratio correction amount to the fuel ratio estimated value to obtain a fuel ratio estimated value. In the control apparatus of the coal-fired power plant according to claim 3,
The mill basic performance calculation function is
The difference between the primary air flow rate included in the measurement signal and a predetermined reference amount of the primary air flow rate, the coal supply amount supplied to the mill included in the measurement signal, and the predetermined supply amount. Finding the difference between the reference amount of the charcoal amount and the difference between the roller pressure oil pressure of the mill included in the measurement signal and the predetermined reference amount of the roller pressure oil pressure,
From these differences and the estimated value of HGI, which is a coal grindability index stored in the mill characteristic information database, calculate the roller lift amount correction amount of the mill,
A coal-fired power plant that estimates the roller lift amount of the mill in standard operation by adding the roller lift amount correction amount to the roller lift amount of the mill included in the measurement signal to obtain the reference roller lift amount of the mill Control device. In the control apparatus of the coal-fired power plant according to claim 3,
The mill basic performance calculation function is
The difference between the primary air flow rate included in the measurement signal and a predetermined reference amount of the primary air flow rate, the coal supply amount supplied to the mill included in the measurement signal, and the predetermined supply amount. Find the difference between the reference amount of the charcoal amount and the difference between the classifier rotational speed of the mill included in the measurement signal and the predetermined reference amount of the classifier rotational speed,
From these differences and the estimated value of HGI, which is a coal grindability index stored in the mill characteristic information database, a correction amount for the pressure difference between the inlet and outlet of the mill is calculated.
Coal-fired power that estimates the differential pressure of the mill in standard operation by adding the correction amount of the differential pressure to the differential pressure of the inlet and outlet of the mill included in the measurement signal to obtain the reference differential pressure of the mill Plant control device. In the control apparatus of the coal-fired power plant according to claim 3,
The mill basic performance calculation function is
The estimated moisture value of the coal being processed in the mill, the fuel ratio of the coal being processed in the estimated mill, the roller lift of the mill in the estimated standard operation, and the mill lift in the estimated standard operation. A control apparatus for a coal-fired power plant that estimates a value of HGI, which is a grindability index of coal being processed in the mill, from the differential pressure, and stores the estimated value of HGI in the mill characteristic information database. In the control apparatus of the coal-fired power plant according to claim 3,
The mill basic performance calculation function is
From the estimated HGI value, the roller pressure oil pressure of the mill included in the measurement signal, and the classifier rotation speed of the mill included in the measurement signal, the amount of coal supplied to the mill, The control apparatus of the coal-fired power plant which estimates the coal output rate which shows the ratio of the quantity of the pulverized coal supplied to the said boiler from the said mill. In the control apparatus of the coal-fired power plant according to claim 3,
The mill basic performance calculation function is
A coal-fired power plant that estimates the atomization index from the estimated HGI value, the roller pressure oil pressure of the mill included in the measurement signal, and the classifier rotation speed of the mill included in the measurement signal. Control device. In the control apparatus of the coal-fired power plant according to claim 3,
The mill efficiency calculation function is
A control apparatus for a coal-fired power plant that estimates the combustion rate of pulverized coal generated by the mill from the mill capacity, C / A value, and atomization index calculated by the mill basic performance calculation function. In the control apparatus of the coal-fired power plant according to claim 3,
The mill efficiency calculation function is
The control apparatus of the coal-fired power plant which calculates the combustion efficiency of the said pulverized coal from the estimated combustion rate and the information regarding the said coal preserve | saved in the said coal information management database. In the control apparatus of the coal-fired power plant according to claim 3,
The mill efficiency calculation function is
From the calculated combustion efficiency and the mill capacity and mill power calculated by the mill basic performance calculation function, the operation efficiency of the coal-fired power plant that calculates the operation efficiency of the mill, which is the value obtained by subtracting the efficiency corresponding to the mill power from the combustion efficiency. Control device. In the control apparatus of the coal-fired power plant according to claim 1,
The coal-fired power plant includes a plurality of the mills,
The mill operation calculator is
Classify the mills into groups,
Evaluation based on an index obtained from the operation efficiency of mills belonging to any one of the groups, and an index considering the balance of operation efficiency between the one arbitrary group and all other groups. Calculate the function,
A control apparatus for a coal-fired power plant that searches for an operation condition of a mill belonging to the one arbitrary group so as to maximize the value of the evaluation function using an optimum search method. In the control apparatus of the coal-fired power plant according to claim 1,
The control apparatus of a coal-fired power plant provided with the input-output part for transmitting / receiving information with an image display apparatus. In the control apparatus of the coal-fired power plant according to claim 14,
A control device for a coal-fired power plant, which displays the mill in association with the arrangement of burners provided in the boiler and is connected to an image display device that displays a screen that allows addition and deletion of the group. In the control apparatus of the coal-fired power plant according to claim 14,
The control apparatus of the coal-fired power plant connected with the image display apparatus which displays the trend graph of the average operating efficiency of the said group, and the trend graph of the operating efficiency obtained from the measurement information of the said coal-fired power plant.

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