JP2014117657A - Control device of coal crusher, and control method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve responsiveness when increasing a coal production amount in response to a load increase in a generator, regardless of a moisture percentage of coal supplied to a mill.SOLUTION: A control device 50 of a coal crusher is provided in a coal crusher for producing fine powdered coal generated by crushing the coal by the mill to a boiler for generating steam for driving the generator, and controls the temperature of the mill. The control device 50 of the coal crusher comprises: a production coal moisture percentage arithmetic operation part 51 for arithmetically operating a production coal moisture percentage M2 of the produced fine powdered coal from various process values in the mill; a temperature command value correction part 52 for adjusting a mill temperature command value by a state of the production coal moisture percentage M2 by adding a PID output value of the production coal moisture percentage M2 to the mill temperature command value to the mill; and a preceding signal arithmetic operation part 53 for correcting the mill temperature command value by adding a preceding signal S of temperature control determined from the production coal moisture percentage M2 to the mill temperature command value in a load variation in the generator.

Description

  The present invention relates to a control device for a coal pulverizer that generates pulverized coal supplied to a boiler or the like of a power plant, and a control method therefor.

  In a coal-fired thermal power plant, coal is pulverized by a coal pulverizer to produce pulverized coal, and the pulverized coal is supplied to a boiler for efficient combustion. If the moisture content of coal is high when pulverizing the coal, the pulverization performance in the mill (pulverization unit) of the coal pulverizer decreases, and after pulverization, only pulverized coal having a predetermined particle size or less is classified by a classifier. When sending out to the boiler side, pulverized coal aggregates and the particle size becomes large, and the rate of returning to the pulverization section increases because it exceeds the size that can pass through the classifier. Therefore, the amount of pulverized coal output decreases.

  For this reason, when supplying coal with a high moisture content, the temperature of the air flow supplied to the inside of the mill is raised to dry the moisture of the pulverized coal and supply it to the boiler. Generally, a mill is provided with a hot air damper that supplies hot air and a cold air damper that supplies cold air (room temperature air). The internal temperature of the mill is adjusted by the opening ratio of these dampers. Yes. When raising the temperature inside the mill, the supply ratio of hot air is increased.

  When increasing the coal supply amount C1 to the mill as the operating load of the generator increases, if the moisture content of coal supplied is high, even if the temperature inside the mill is raised, A response delay occurred in the increase in the amount of coal, and this response delay was a disturbance in the steam temperature and steam pressure control of the boiler, and stable control could not be performed.

  Conventionally, in order to suppress the coal output delay due to the moisture content of such coal, as in the boiler control device described in Patent Document 1, the inlet air temperature of the mill, the outlet air temperature, the mill casing temperature, The boiler heat input and output heat are calculated from the coal temperature, coal flow rate, mill inlet air flow rate, etc., and the properties and moisture content of the coal are calculated from these balances. Some adjusted the pulverized coal particle size at the outlet.

Japanese Patent No. 4374298

  However, since the boiler control device disclosed in Patent Document 1 adjusts the pulverized coal particle size according to the properties and moisture content of the coal, when the load on the generator is increased, the boiler control device is appropriate. There was a problem that a response delay occurred before the amount of charcoal was reached, and a time lag occurred before the load on the generator increased.

  The present invention has been made in view of the above circumstances, and improves the responsiveness when increasing the coal output in accordance with the load increase of the generator regardless of the moisture content of the coal supplied to the mill. It is an object of the present invention to provide a control device and a control method for a coal pulverizing apparatus.

In order to solve the above problems, the present invention employs the following means.
That is, the control device of the coal pulverization apparatus according to the present invention is provided in a coal pulverization apparatus that outputs pulverized coal generated by pulverizing coal by a mill to a boiler that generates steam for driving a generator. A coal pulverization apparatus for controlling the temperature of the coal pulverization apparatus, which calculates a coal moisture content of the pulverized coal to be discharged from various process values in the mill; A temperature command value correction unit that adjusts the mill temperature command value according to the state of the coal output moisture content by adding the PID output value of the moisture content as a correction amount to the mill temperature command value to the mill; and the generator And a preceding signal calculation unit that adds a preceding signal of temperature control obtained from the coal output moisture content to the mill temperature command value and corrects the mill temperature command value when the load changes. And

  According to the above configuration, the coal output moisture rate calculation unit calculates the coal output moisture rate of pulverized coal discharged from the mill, and the temperature command value correction unit calculates the PID output value of the coal output moisture rate as a correction amount. Is added to the mill temperature command value, and the mill temperature command value is adjusted according to the state of the coal output moisture content. When the load on the generator fluctuates, a preceding signal for temperature control obtained from the coal output moisture content is added to the mill temperature command value in the preceding signal calculation unit, and the mill temperature command value is corrected.

  For this reason, for example, even if the generator load is increased when the moisture content of coal supplied to the mill is high, the preceding signal calculation unit adds the preceding signal of the temperature control to the mill temperature command value. The mill temperature is controlled to rise prior to the coal output timing, and drying of coal to be fed and pulverized pulverized coal is promoted. Therefore, it is possible to improve the responsiveness when increasing the coal output in accordance with the load increase of the generator.

  The said structure WHEREIN: It is preferable that the said preceding signal calculating part enlarges the change width of the said preceding signal, so that the load change width of the said generator is large.

Further, in the above configuration, it is preferable that the preceding signal calculation unit sets the increasing rate of increase of the preceding signal as the load change rate of the generator increases.
Furthermore, in the said structure, it is preferable that the said prior | preceding signal calculating part sets the change width of the said prior | preceding signal large, so that the said coal output moisture rate becomes high.

  Furthermore, in the above-described configuration, it is preferable that the preceding signal calculation unit sets a rate limit of the rate of change of the preceding signal as the coal output moisture ratio increases.

  With each of the above preferred settings, the responsiveness when increasing the coal output can be further improved.

  Moreover, the said structure WHEREIN: It is preferable that the said coal output moisture rate is calculated from the correlation of the moisture rate of the coal supplied to the said mill, and the drying efficiency in the said mill.

  Thereby, the moisture content of the pulverized coal discharged from the mill can be accurately calculated, and the value of the preceding signal calculated in the preceding signal calculation unit can be optimized to improve the output response.

  Further, the control method of the coal pulverizing apparatus according to the present invention is provided in a coal pulverizing apparatus that outputs pulverized coal generated by pulverizing coal by a mill to a boiler that generates steam for driving a generator, The control method of the coal pulverizing apparatus for controlling the temperature of the coal, calculating the coal moisture content of the pulverized coal from the various process values in the mill, and calculating the PID output value of the coal moisture content By adding to the mill temperature command value to the mill as a correction amount, the mill temperature command value is adjusted according to the state of the coal output moisture rate, and obtained from the coal output moisture rate when the load of the generator changes. A temperature control preceding signal is added to the mill temperature command value to correct the mill temperature command value.

  According to the above control method, for example, even if the generator load is increased when the moisture content of coal supplied to the mill is high, the preceding signal of temperature control is added to the mill temperature command value, The mill temperature is controlled to rise prior to the coal output timing, and drying of coal to be fed and pulverized pulverized coal is promoted. Therefore, it is possible to improve the responsiveness when increasing the coal output in accordance with the load increase of the generator.

  As described above, according to the control device and the control method of the coal pulverizer according to the present invention, the coal output is increased in accordance with the load increase of the generator regardless of the moisture content of the coal supplied to the mill. Responsiveness in case can be improved.

It is a longitudinal cross-sectional view which shows an example of the coal grinding | pulverization apparatus which can apply this invention. It is a block diagram which shows the structure of the control apparatus which concerns on one Embodiment of this invention. It is a control flowchart which calculates | requires a coal output moisture rate. It is a control flowchart which shows how to obtain | require a preceding signal in a preceding signal calculating part.

Hereinafter, embodiments of the present invention will be described with reference to FIGS.
FIG. 1 is a longitudinal sectional view showing an example of a coal crusher to which the present invention can be applied. The coal pulverizing apparatus 1 has a well-known configuration for generating pulverized coal supplied to a boiler of a power plant, and a mill (grinding part) 2 has a hollow cylindrical housing (housing) 3. I have. A coal supply pipe 4 is mounted so as to vertically enter the inside of the housing 3 from the center of the zenith of the housing 3, and a lower end portion thereof is opened to the inside of the housing 3.

  A dish-shaped crushing table 5 is disposed in the lower part of the housing 3 so as to face the opening of the coal supply pipe 4, and is rotated by a table driving mechanism 6. A plurality of crushing rollers 7 are arranged so as to be able to be separated from and contacted with the peripheral edge of the upper surface of the crushing table 5. These crushing rollers 7 are rotatably supported by a support device 8 and are pressed against the crushing table 5 by a pressing drive device 9.

  Inside the housing 3, a centrifugal classifier 11 is rotatably supported around the coal supply pipe 4, and is rotationally driven by a classifier driving device 12 installed at the top of the housing 3. Yes. The rotational speed of the classifier 11 is controlled by a control device described later.

  A primary air supply pipe 13 is connected to the housing 3 at a position lower than the crushing table 5. The primary air supply pipe 13 supplies primary air supplied from an air supply device (not shown) into the housing 3 at a high speed. This primary air is hot air in which hot air heated by heat exchange with boiler exhaust heat or the like and cold air at normal temperature are mixed at a predetermined ratio, and the hot air damper and the cold air damper (not shown) are opened. The internal temperature of the housing 3 is adjusted by the degree ratio.

  An outlet pipe 15 is connected to the zenith portion of the housing 3. The outlet pipe 15 leads to a boiler furnace (burner) (not shown).

The coal supply pipe 4 supplies coal onto the crushing table 5 from a coal supply device (not shown). The coal supply pipe 4 is provided with a flow rate sensor 17 for measuring the coal supply amount C1 and a temperature sensor 18 for measuring the coal supply temperature.
The primary air supply pipe 13 includes a flow rate sensor 20 that measures the flow rate of primary air, that is, the inlet air flow rate of the mill 2, and a temperature sensor 21 that measures the temperature of primary air, that is, the inlet air temperature of the mill 2. Is provided.
Further, the outlet pipe has a pressure sensor 23 for measuring the outlet pressure of the mill 2, a temperature sensor 24 for measuring the outlet air temperature of the mill 2, and a pressure sensor 25 for measuring a differential pressure between the mill 2 and the furnace. Is provided.

  In the coal pulverizing apparatus 1 configured as described above, the coal supplied onto the pulverizing table 5 from the coal supply pipe 4 moves to the outer peripheral side by the centrifugal force accompanying the rotation of the pulverizing table 5, and pulverizes with the pulverizing roller 7. It enters the table 5 and is crushed. At this time, since the crushing roller 7 is pressed toward the crushing table 5 by the pressing drive device 9, the crushing roller 7 rotates in conjunction with the rotation of the crushing table 5.

  The coal is pulverized by the pulverizing roller 7 to become pulverized coal, and is conveyed upward by primary air flowing into the mill 2 (housing 3) from the primary air supply pipe 13 at the lower part of the pulverizing table 5. Particle size is classified. Only fine particles having a predetermined particle diameter or less are supplied together with air from the outlet pipe 15 to the boiler furnace. Fine particles have good ignitability and can be efficiently burned by a boiler burner. On the other hand, particles having a large particle size are repelled by the rotating blades of the classifier 11 and fall on the pulverizing table 5, and are pulverized again by the pulverizing roller 7, and the particle size is further reduced and passed through the classifier 11 to the boiler furnace. Supplied.

  As described above, the primary air supplied from the primary air supply pipe 13 to the inside of the mill 2 is hot air in which high-temperature hot air and normal-temperature cold air are mixed at a predetermined ratio. The moisture contained in the coal supplied to the coal and the pulverized coal produced by pulverizing the coal can be dried. As the moisture content of coal and pulverized coal increases, the opening ratio of the hot air damper is increased and the temperature of the primary air is increased.

FIG. 2 is a block diagram illustrating a configuration of a control device according to an embodiment of the present invention.
The control device 50 controls the temperature of the mill 2, preferably the outlet air temperature of the mill 2 measured by the temperature sensor 24, and includes a coal output moisture rate calculating unit 51, a temperature command value correcting unit 52, And a preceding signal calculation unit 53.

  The coal output moisture rate calculating unit 51 calculates the coal output moisture rate M2 of the pulverized coal to be output from various process values in the mill 2. Here, various process values include a mill inlet air flow rate measured by the flow sensor 20, a mill inlet air temperature measured by the temperature sensor 21, a mill outlet air temperature measured by the temperature sensor 24, and a flow rate. The coal supply amount C1 from the coal supply pipe 4 measured by the sensor 17, the coal supply temperature measured by the temperature sensor 18, the mill 2 and the boiler furnace (not shown) measured by the pressure sensor 25, And the pressure at the outlet of the mill measured by the pressure sensor 23.

  The coal output moisture rate M2 calculated by the coal output moisture rate calculating unit 51 is calculated as a difference 55 from the target coal output moisture rate setting value, and this difference 55 is calculated by the temperature command value correcting unit 52. This is a correction amount to the mill outlet air temperature command value (mill temperature command value) with respect to the command value. In the function generator 57, the relationship between the mill outlet air temperature command value and the coal feed amount command value is as shown in a graph 2A in FIG. The temperature command value correction unit 52 adds the calculated PID output value of the difference 55 of the coal output moisture content M2 as a correction amount to the uncorrected mill outlet air temperature command value determined by the function generation unit 57. Thus, the mill outlet air temperature command value is corrected according to the state of the coal output moisture content M2.

  By the way, it is preferable to set the coal output moisture M2 from the correlation between the moisture content of coal fed to the mill 2 and the drying efficiency η in the mill 2. In the coal output moisture rate calculating unit 51 shown in FIG. 2, a control flow as shown in FIG. 3 is executed in order to obtain the coal output moisture rate M2.

  That is, first, the coal output calculation unit 51a calculates the coal output C2 from the mill 2 from the mill furnace differential pressure, the mill inlet air flow rate, the mill outlet air temperature, and the mill outlet pressure. In short, from the differential pressure between the air flowing into the mill 2 and the air flowing out of the mill 2, it is calculated how much the amount of coal output C2 is contained in the flowing air.

  Next, the coal supply moisture rate calculating unit 51b calculates the coal supply moisture rate M1. Here, in order to calculate the moisture content of coal supply from the heat balance in the furnace (ratio of heat input to heat output), the mill inlet air flow rate, the mill inlet air temperature, the mill outlet air temperature, and the coal supply amount C1. Then, the coal supply moisture percentage M1 is calculated from the coal supply temperature, the coal output C2 calculated by the coal output calculator 51a, and the drying efficiency η described later. The calculation of the coal supply moisture content M1 needs to be performed under conditions where the mill 2 is stationary.

  Further, the drying efficiency η is set in the drying efficiency table 51c. The drying efficiency table 51c uses the values of the coal feed moisture percentage M1 calculated by the coal feed moisture percentage calculator 51b, the mill inlet air flow rate, the mill outlet air temperature, and the coal feed amount C1 as parameters. An assumed value of η is set.

  Then, in the coal output moisture rate calculation unit 51, the coal supply moisture rate M1 calculated by the coal supply moisture rate calculation unit 51b, the assumed value of the drying efficiency η set in the drying efficiency table 51c, and the coal supply amount C1 From the value, the coal output moisture content M2 is calculated.

  In the above control, the assumed value of the drying efficiency η set in the drying efficiency table 51c is substituted into the coal supply moisture rate calculating unit 51b and used for calculating the coal supply moisture rate M1, and this coal supply moisture rate calculating unit. The routine is repeated in which the coal supply moisture content M1 calculated in 51b is again substituted into the drying efficiency table 51c, and the assumed value of the drying efficiency η is reset. This iterative calculation is repeated until the difference between the drying efficiency η on the inlet side of the mill 2 and the drying efficiency η on the outlet side converges within a predetermined range. Such an iterative calculation is performed because the drying efficiency η cannot be calculated unless the moisture content of the coal supply is determined.

  Thus, by calculating the coal output moisture content M2 based on the correlation between the moisture content M1 of coal supplied to the mill 2 and the drying efficiency η in the mill 2, the fine powder discharged from the mill 2 is calculated. The moisture content M2 of charcoal can be calculated accurately.

  According to the control so far, even when the moisture content M1 of the coal fed to the mill 2 is high, the internal temperature of the mill 2 is increased accordingly, and the coal fed into the mill 2 and Drying of the pulverized pulverized coal is promoted, and the responsiveness when the load on the generator fluctuates can be improved to some extent.

  Further, as shown in FIG. 2, when the load on the generator fluctuates, the preceding signal S of the temperature control obtained from the coal output moisture rate M2 in the preceding signal calculation unit 53 is the corrected mill outlet air temperature command value. The mill outlet air temperature command value is further corrected. The preceding signal calculation unit 53 is assigned the generator load, the change width and rate of change of the generator load command, and the coal output moisture rate M2 calculated by the coal output moisture rate calculation unit 51, and the preceding signal S is substituted. Calculated.

  As shown in the graph 2B in FIG. 2, the preceding signal calculation unit 53 sets the change width Hb of the preceding signal S to be larger as the load change width Ha of the generator is larger. Further, the preceding signal calculation unit 53 sets the increasing rate of change Rb of the preceding signal S to be larger as the load change rate Ra of the generator is larger. That is, the slope of the raising side change rate Rb is set to a steep angle. Note that the lower side change rate Rc is not particularly required to be a steep angle like the higher side change rate Rb. In addition, a predetermined holding time is provided during the transition from the increase side change rate Rb to the decrease side change rate Rc.

  FIG. 4 is a control flow diagram showing how to obtain the preceding signal S in the preceding signal calculation unit 53. The preceding signal calculation unit 53 is provided with five function generation units 53a to 53e. First, in the function generator 53a, as shown in the graph 4A, a correction amount curve serving as a base is set as a function according to the generator load band (50%, 60%, 70%, etc.). Then, the change width Hb of the preceding signal S is set to be larger so that the increase width of the generator load (load change width Ha) is larger, the increase width of the mill outlet air temperature is larger.

  Further, in the function generator 53b, as shown in the graph 4B, as the load change rate Ra of the generator becomes larger (as the slope becomes steeper), the change rate of the preceding signal S, particularly here, the higher side change rate. The calculation coefficient is set so that Rb (see FIG. 2) becomes large (so that the slope becomes steep).

  Further, in the function generator 53c, as shown in the graph 4C, the calculation coefficient is set so that the change width Hb of the preceding signal S increases as the coal output moisture rate M2 increases.

  Moreover, in the function generation part 53d, as shown in graph 4D, the rate limit of the rate of change on the temperature raising side of the preceding signal S is set larger as the coal output moisture rate M2 becomes higher. In the function generation part 53e, As shown in the graph 4E, the rate limit of the rate of change on the temperature lowering side of the preceding signal S is set larger as the coal output moisture rate M2 becomes higher.

The control device 50 is configured as described above.
As described above, the control device 50 includes a coal output moisture rate calculating unit 51 for calculating the coal output moisture rate M2 of the pulverized coal to be output from various process values in the mill 2, and the coal output moisture rate. By adding the PID output value of M2 as a correction amount to the mill temperature command value to the mill 2, the temperature command value correction unit 52 that adjusts the mill temperature command value according to the state of the coal output moisture content M2, and the generator A preceding signal calculation unit 53 that adds a temperature control preceding signal S obtained from the coal output moisture content M2 to the mill temperature command value and corrects the mill temperature command value when the load fluctuates.

  When the load on the generator fluctuates, the preceding signal calculation unit 53 adds the temperature control preceding signal S obtained from the coal output moisture content M2 to the mill temperature command value, thereby correcting the mill temperature command value.

  For this reason, for example, even if it becomes the driving | running condition which raises a generator load when the moisture content of the coal supplied to the mill 2 becomes high, the preceding signal calculating part 53 adds the preceding signal S of temperature control to a mill temperature command value. Thus, the outlet air temperature of the mill 2 is controlled to rise prior to the actual coal output timing, and drying of coal to be supplied and pulverized coal is promoted. Therefore, the responsiveness in the case of increasing the coal output C2 in accordance with the load increase of the generator can be dramatically improved.

  In this control device 50, the preceding signal calculation unit 53 sets the change width Hb of the preceding signal S to be larger as the load change width Ha of the generator is larger. By doing this, when the load change width Ha is large, drying in the mill 2 can be further accelerated to reduce a delay in the response of the coal output, and load followability can be improved.

  Furthermore, since the preceding signal calculation unit 53 sets the increasing rate of increase of the preceding signal S as the load change width Ha of the generator increases, the increasing range of the outlet air temperature of the mill 2 in advance according to the load changing width Ha. When the load change width Ha is large, the drying in the mill 2 can be further accelerated to reduce the delay in the response of the coal output, and the load followability can be improved.

  Moreover, since the preceding signal calculation part 53 sets the variation | change_range of the preceding signal S so that the coal output moisture rate M2 becomes high, according to the coal output moisture rate M2, the raise range of the exit air temperature of the mill 2 is enlarged beforehand. In addition, by reducing the drying delay in the mill 2 when the coal output moisture content M2 is large, the response delay of the coal output can be reduced and the load followability can be improved.

  Furthermore, since the preceding signal calculation unit 53 sets the rate limit of the rate of change of the preceding signal S as the coal output moisture rate M2 becomes higher, the outlet air temperature of the mill 2 is previously set according to the coal output moisture rate M2. By increasing the speed at which the coal is discharged and reducing the drying delay in the mill 2 when the coal output moisture content M2 is large, the response delay of the coal output can be reduced and the load followability can be improved.

  Further, in this control device 50, the coal output moisture rate M2 of the pulverized coal discharged from the mill 2 is calculated from the correlation between the moisture content of the coal supplied to the mill 2 and the drying efficiency η in the mill 2. Therefore, the coal output moisture rate M2 can be accurately calculated, and the value of the preceding signal S calculated by the preceding signal calculating unit 53 can be optimized to improve the coal output responsiveness.

  Thus, according to the control device and the control method of the coal pulverizer according to the present invention, regardless of the moisture content of the coal supplied to the mill 2, the coal output C2 is increased in accordance with the load increase of the generator. Responsiveness can be improved.

  It should be noted that the present invention is not limited to the configuration of the above-described embodiment, and can be appropriately modified or improved within a scope not departing from the gist of the present invention. Are also included in the scope of rights of the present invention.

  For example, in the above embodiment, it has been described that the outlet air temperature of the mill 2 is adjusted in advance by the preceding signal S, but the inlet air temperature of the mill 2 and the inlet air flow rate of the mill 2 are adjusted in advance. May be.

DESCRIPTION OF SYMBOLS 1 Coal crusher 2 Mill 50 Control apparatus 51 Coal discharge moisture rate calculating part 52 Temperature command value correction | amendment part 53 Leading signal calculating part Ha The load change width Hb of a generator M1 Coal feed moisture ratio M2 Ra Generator load change rate Rb Advance signal increase side change rate Rc Advance signal decrease side change rate S Advance signal η Drying efficiency in the mill

Claims (7)

A pulverized coal produced by pulverizing coal with a mill is provided in a coal pulverization device that outputs to a boiler that generates steam for driving a generator, and is a control device for a coal pulverization device that controls the temperature of the mill. ,
From various process values in the mill, a coal output moisture rate calculating unit for calculating the coal output moisture rate of the pulverized coal to be output,
A temperature command value correction unit that adjusts the mill temperature command value according to the state of the coal output moisture rate by adding the PID output value of the coal output moisture rate as a correction amount to the mill temperature command value to the mill;
At the time of load fluctuation of the generator, a preceding signal for temperature control obtained from the coal output moisture content is added to the mill temperature command value, and a preceding signal calculation unit for correcting the mill temperature command value;
The control apparatus of the coal grinding | pulverization apparatus characterized by comprising.   2. The control apparatus for a coal pulverizer according to claim 1, wherein the preceding signal calculation unit sets the change width of the preceding signal to be larger as the load change width of the generator is larger.   3. The control apparatus for a coal pulverizer according to claim 1, wherein the preceding signal calculation unit sets the increasing rate of change of the preceding signal to be larger as the load change rate of the generator is larger.   The control device for a coal pulverizer according to any one of claims 1 to 3, wherein the preceding signal calculation unit sets the change width of the preceding signal to be larger as the coal output moisture ratio becomes higher.   5. The coal pulverization apparatus according to claim 1, wherein the preceding signal calculation unit sets a rate limit of a rate of change of the preceding signal as the coal output moisture ratio increases. Control device.   The coal according to any one of claims 1 to 5, wherein the coal output moisture content is calculated from a correlation between a moisture content of coal supplied to the mill and a drying efficiency in the mill. Control device for crushing equipment. A control method for a coal pulverizer for controlling the temperature of the mill, which is provided in a coal pulverizer that outputs pulverized coal produced by pulverizing coal with a mill to a boiler that generates steam for driving a generator. ,
From various process values in the mill, calculate the coal moisture content of the pulverized coal to be discharged,
By adding the PID output value of the coal output moisture content as a correction amount to the mill temperature command value to the mill, the mill temperature command value is adjusted according to the state of the coal output moisture content,
At the time of load fluctuation of the generator, a preceding signal for temperature control obtained from the coal output moisture content is added to the mill temperature command value to correct the mill temperature command value.
A control method for a coal pulverizer.

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