JP2019120188A - Integrated control device and integrated control method for steam turbine - Google Patents

Abstract

To provide an integrated control device capable of integrally controlling a plurality of steam turbines.SOLUTION: An integrated control device 50 is configured to integrally control a plurality of steam turbines 2 which rotate with steam generated in one or plural boilers 1. Specifically, the integrated control device 50 is configured to change an operational state of a first steam turbine 2A, which is one of the plurality of steam turbines 2 and in which speed regulation control is executed, according to an operational state of a second steam turbine 2B, which is another one of the plurality of steam turbines and in which front pressure control is executed.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to an integrated control device and an integrated control method of a steam turbine.

  DESCRIPTION OF RELATED ART Conventionally, the operation control apparatus of the single steam turbine generator (combination of a steam turbine and a generator) using the steam which generate | occur | produces with a boiler is known (refer patent document 1).

  This operation control device switches the pressure regulation control of the corresponding steam turbine to the speed control control when the power generated by a single generator exceeds the generator rated power, and thereafter, the generated power is the generator rated power It is configured to return to pressure regulation control when the main steam pressure becomes lower than the set pressure below. With this configuration, steam generated by the boiler is used as much as possible for power generation to achieve effective use of the steam, and it is also possible to automatically cope with fluctuations in the amount of steam generated.

Unexamined-Japanese-Patent No. 2000-265804

  However, the above-described operation control device is only used to control a single steam turbine, and can not control a plurality of steam turbines in an integrated manner.

  Therefore, it is desirable to provide an integrated control device that can control a plurality of steam turbines in an integrated manner.

  The integrated control device for a steam turbine according to an embodiment of the present invention is an integrated control device that integrally controls a plurality of steam turbines that rotate using steam generated by one or more boilers, One of the steam turbines, an operating state of a first steam turbine for which speed control is performed, and another one of the plurality of steam turbines, for which prepressure control is performed It is configured to change according to the operating state of the steam turbine.

  By the above-mentioned means, an integrated control device is provided which controls a plurality of steam turbines in an integrated manner.

It is a figure which shows the structural example of the electric power generation system containing the integrated control apparatus which concerns on one Embodiment of this invention. It is a figure which shows the time transition of the generated electric power of the steam turbine contained in the electric power generation system of FIG. It is a flowchart which shows an example of integrated processing. It is a figure which shows another structural example of the 2nd steam turbine which operate | moves by pre-pressure control.

  An integrated control device 50 according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a diagram showing a configuration example of a power generation system 100 including an integrated control device 50. As shown in FIG. In FIG. 1, a dashed-dotted line represents a steam pipe, a broken line represents a hydraulic fluid pipe, a dotted line represents an electrical signal line, and a dashed-two dotted line represents a power line.

  The power generation system 100 is a system that generates steam by supplying steam generated from the boiler 1 to a plurality of steam turbines in a nonferrous metal smelting plant. Therefore, the power generation system 100 includes, for example, the boiler 1, the steam turbine 2, the steam control valve 3, the generator 4, the condenser 5, the steam pressure sensor 6, the rotation speed sensor 7, the electric power sensor 8, the hydraulic pressure source 9, the bleed flow adjustment It includes a valve 10, a bleed pressure sensor 11, a safety valve 12, a governor mechanism 15, an integrated control device 50 and the like.

  The boiler 1 is a device that generates steam. In the example of FIG. 1, the boiler 1 includes a first boiler 1A, a second boiler 1B, and a third boiler 1C. The number of boilers 1 may be one. The steam pipe SL is configured such that steam generated in each of the first boiler 1A, the second boiler 1B, and the third boiler 1C merges and is supplied to the steam turbine 2.

  The steam turbine 2 is an external combustion engine that converts energy of steam into rotational motion through a turbine (impeller) and a shaft. In the example of FIG. 1, the steam turbine 2 includes a first steam turbine 2A and a second steam turbine 2B. The speed control is performed in the first steam turbine 2A, and the pressure control (pre-pressure control) is performed in the second steam turbine 2B. The speed control is control for maintaining the generated power at the set power regardless of fluctuations in the amount of steam. Pre-pressure control is control that maintains the pressure of the steam supplied to the steam turbine at a set pressure. Therefore, in the prepressure control, the generated power fluctuates according to the fluctuation of the amount of steam.

  The steam control valve 3 is a valve that increases or decreases the pressure of the steam supplied to the steam turbine 2. In the example of FIG. 1, the steam control valve 3 includes a first steam control valve 3A and a second steam control valve 3B. The first steam control valve 3A is a valve that increases or decreases the pressure of the steam supplied to the first steam turbine 2A. The second steam control valve 3B is a valve that increases or decreases the pressure of the steam supplied to the second steam turbine 2B.

  The generator 4 is a device that converts the rotational motion of the steam turbine 2 into electricity to generate electricity. In addition, the generator 4 supplies the generated power to the external electric load of the power generation system 100 through the power line EL. The external electrical load may be an internal electrical load of a non-ferrous metal smelting plant or an external electrical load of a non-ferrous metal smelting plant. In the example of FIG. 1, the generator 4 includes a first generator 4A and a second generator 4B. The first generator 4A is connected to the rotation shaft of the first steam turbine 2A. The first generator 4A is configured to be able to supply power to an external electrical load through the first power line ELA. The 2nd generator 4B is connected with the axis of rotation of the 2nd steam turbine 2B. The second generator 4B is configured to be able to supply power to an external electrical load through the second power line ELB.

  The condenser 5 is configured to cool and condense the steam used in the steam turbine 2 back to water by heat exchange with the cooling water. The condenser 5 can reduce the pressure in the steam turbine 2 by reducing the volume by returning the steam to water, and the flow of the steam can be improved to increase the efficiency of the steam turbine 2. In the example of FIG. 1, the condenser 5 includes a first condenser 5A and a second condenser 5B. The first condenser 5A returns the steam used in the first steam turbine 2A to water. The second condenser 5B returns the steam used in the second steam turbine 2B to water.

  The steam pressure sensor 6 is configured to measure the pressure of steam in a steam pipe SL connecting the boiler 1 and the steam turbine 2. In the example of FIG. 1, the vapor pressure sensor 6 includes a first vapor pressure sensor 6A and a second vapor pressure sensor 6B. The first steam pressure sensor 6A measures the pressure of steam in the steam pipe SLA connecting the boiler 1 and the first steam turbine 2A. The second steam pressure sensor 6B measures the pressure of steam in the steam pipe SLB connecting the boiler 1 and the second steam turbine 2B.

  The rotation speed sensor 7 is configured to measure the rotation speed of the rotation shaft of the steam turbine 2. In the example of FIG. 1, the rotation speed sensor 7 includes a first rotation speed sensor 7A and a second rotation speed sensor 7B. The first rotation speed sensor 7A measures the rotation speed of the rotation shaft of the first steam turbine 2A. The second rotation speed sensor 7B measures the rotation speed of the rotation shaft of the second steam turbine 2B.

  The power sensor 8 is configured to measure the generated power generated by the generator 4. In the example of FIG. 1, the power sensor 8 includes a first power sensor 8A and a second power sensor 8B. The first power sensor 8A measures the generated power of the first generator 4A. The second power sensor 8B measures the generated power of the second generator 4B.

  The hydraulic source 9 is a device that supplies hydraulic fluid to hydraulic devices. In the example of FIG. 1, the hydraulic pressure source 9 is a hydraulic pump that can be controlled by the integrated control device 50, and supplies hydraulic fluid to hydraulic devices through the hydraulic fluid line HL. The hydraulic pressure source 9 may be, for example, a hydraulic pump that operates autonomously to maintain a predetermined discharge pressure regardless of the presence or absence of a control command from the integrated control device 50. Specifically, the hydraulic pressure source 9 supplies hydraulic fluid to hydraulic equipment related to the first steam turbine 2A through the hydraulic fluid line HLA. Further, the hydraulic source 9 supplies hydraulic oil to hydraulic equipment related to the second steam turbine 2B through the hydraulic oil pipe HLB.

  The bleed control valve 10 is a valve that increases or decreases the pressure of the steam extracted from the steam turbine 2. In the example of FIG. 1, the extraction valve 10 includes a first extraction valve 10A and a second extraction valve 10B. The first bleed control valve 10A is a hydraulic valve that increases or decreases the pressure of the steam extracted from the first steam turbine 2A. The second bleed control valve 10B is a solenoid valve that increases or decreases the pressure of the steam extracted from the second steam turbine 2B.

  The bleed pressure sensor 11 is configured to measure the pressure of the bleed air at the bleed pipe XL extending from the steam turbine 2. In the example of FIG. 1, the bleed pressure sensor 11 includes a first bleed pressure sensor 11A and a second bleed pressure sensor 11B. The first bleed pressure sensor 11A measures the pressure of the bleed air at the bleed pipe XLA extending from the first steam turbine 2A. The second bleed pressure sensor 11B measures the pressure of the bleed air at the bleed pipe XLB extending from the second steam turbine 2B. The first bleed pressure sensor 11A can adjust the opening degree of the first bleed adjustment valve 10A by outputting a control command according to the magnitude of the pressure of the bleed air in the bleed pipe XLA to the first bleed adjustment valve 10A. Is configured.

  The safety valve 12 is configured to operate when the pressure of the steam in the steam pipe SL rises or falls excessively. In the example of FIG. 1, the safety valve 12 includes a first safety valve 12A and a second safety valve 12B. The first safety valve 12A is a hydraulic valve that shuts off the steam pipe SLA when the pressure of the steam in the steam pipe SLA rises or falls excessively. The second safety valve 12B is a hydraulic valve that shuts off the steam pipe SLB when the pressure of the steam in the steam pipe SLB rises or falls excessively.

  The governor mechanism 15 is a mechanism that controls the steam turbine 2. In the example of FIG. 1, the governor mechanism 15 includes a first governor mechanism 15A and a second governor mechanism 15B. The first governor mechanism 15A is a mechanical governor mechanism that controls the first steam turbine 2A. The second governor mechanism 15B is an electronic governor mechanism that controls the second steam turbine 2B.

  The first governor mechanism 15A is basically configured to be able to control the first steam turbine 2A regardless of the control of the second steam turbine 2B by the second governor mechanism 15B. Similarly, the second governor mechanism 15B is basically configured to be able to control the second steam turbine 2B regardless of the control of the first steam turbine 2A by the first governor mechanism 15A. And since the first steam turbine 2A and the second steam turbine 2B share the boiler 1 as a steam source, the first steam turbine 2A can be a disturbance factor of the second steam turbine 2B, and the second steam turbine 2B It may be a disturbance factor of the first steam turbine 2A.

  The integrated control device 50 is a device that controls the plurality of governor mechanisms 15 in an integrated manner. In the example of FIG. 1, the integrated control device 50 is configured to be able to integrally and automatically control the first governor mechanism 15A and the second governor mechanism 15B which can operate independently of each other. However, even if the second governor mechanism 15B is automatically controlled, the first governor mechanism 15A may be manually operated by the turbine driver.

  The first governor mechanism 15A includes a turbine control board 15a, a governor 15b, a governor motor 15c, a load limiter 15d, and an opening degree transmitter 15e. The turbine control panel 15a is configured to control the governor 15b such that the power generated by the first steam turbine 2A to which the speed control is applied is the set power. Specifically, the governor motor 15c and the load limiter 15d are operated based on information output by at least one of the first steam pressure sensor 6A, the first rotation speed sensor 7A, the first power sensor 8A, and the integrated control device 50. It is configured to control the governor 15b.

  The governor 15 b is configured to be able to increase or decrease the opening degree of the first steam control valve 3 A by using the hydraulic oil discharged by the hydraulic pressure source 9 and the driving force of the governor motor 15 c. Further, the movement of the governor 15b is configured to be limited by the load limiter 15d. That is, the adjustment range of the opening degree of the first steam control valve 3A is configured to be limited by the load limiter 15d. The governor motor 15c is configured to determine the magnitude of the driving force in accordance with a command from the turbine control panel 15a. The load limiter 15d is configured to determine at least one of the maximum value and the minimum value of the opening degree of the first steam control valve 3A in accordance with a command from the turbine control board 15a. For example, the governor 15b can increase the maximum value of the opening of the first steam control valve 3A when the restriction by the load limiter 15d is relaxed, and when the restriction by the load limiter 15d is strengthened (1) The maximum value of the opening degree of the steam control valve 3A will be reduced.

  The opening degree transmitter 15e is a device that measures the opening degree of the first steam control valve 3A. The opening degree transmitter 15e is configured to transmit information on the opening degree of the first steam control valve 3A to the integrated control device 50. The opening degree transmitter 15e may transmit information related to the opening degree of the first steam control valve 3A to the integrated control device 50 via the turbine control board 15a. With this configuration, the integrated control device 50 can grasp the opening degree of the first steam control valve 3A in real time, and can quickly update the set power of the speed control performed in the first steam turbine 2A.

  The second governor mechanism 15B includes a turbine control unit 15f and an electro-hydraulic converter 15g. The turbine control unit 15 f is configured to control the electro-hydraulic transducer 15 g such that the pressure of the steam supplied to the second steam turbine 2 B to which the pre-pressure control is applied becomes the set pressure. Specifically, the electrohydraulic transducer 15g is controlled based on information output by at least one of the second steam pressure sensor 6B, the second rotation speed sensor 7B, the second power sensor 8B, and the integrated control device 50. It is done.

  The electrohydraulic converter 15g is configured to be able to increase or decrease the opening degree of the second steam control valve 3B by using the hydraulic oil discharged by the hydraulic pressure source 9. Specifically, the electrohydraulic converter 15g increases or decreases the pressure of the hydraulic oil acting on the second steam control valve 3B according to the command from the turbine control unit 15f, thereby the opening degree of the second steam control valve 3B. It is configured to be able to increase or decrease the

  Next, integrated control by the integrated control device 50 will be described with reference to FIG. FIG. 2 is a diagram showing temporal transition of the generated power of the steam turbine 2. Specifically, the generated power of each of the first steam turbine 2A and the second steam turbine 2B shifts in the order of FIG. 2 (A) to FIG. 2 (F) as time passes.

  When the operation of the boiler 1 is started, steam is generated to increase the amount of steam. While the amount of steam is small, the generated power of the first steam turbine 2A to which the speed control is applied is at a relatively low level as shown in FIG. 2 (A). This is because, for example, the set power of the speed control is set to a first set value (for example, 1000 [kW]), which is a relatively low value that can be covered by the generated steam amount. Similarly, the generated power of the second steam turbine 2B to which the prepressure control is applied is also at a relatively low level (for example, 1800 [kW]), as shown in FIG. 2 (A). This is because the amount of steam is relatively small.

  Thereafter, as the amount of steam increases, the pressure of steam in the steam pipe SL tends to increase. Therefore, the turbine control unit 15f of the second governor mechanism 15B monitors the output of the second steam pressure sensor 6B while maintaining the pressure of steam in the steam pipe SLB at the set pressure. Increase the opening degree of As a result, the power generated by the second steam turbine 2B increases with the increase in the amount of steam as indicated by the white arrows in FIG. 2 (A).

  Thereafter, when the power generated by the second steam turbine 2B reaches the first upper limit threshold (for example, 6000 [kW] indicated by a broken line in FIG. 2B), the integrated control device 50 is executed by the first steam turbine 2A. Update the set power of the speed control. This is because it is assumed that the pressure of the steam in the steam pipe SL is sufficiently high. Specifically, when the integrated control device 50 determines that the generated power of the second steam turbine 2B has reached the first upper limit threshold based on the output of the second power sensor 8B, the integrated control device 50 is executed by the first steam turbine 2A The set power of the speed control is updated to a larger second set value (for example, 4000 [kW] indicated by an alternate long and short dash line in FIG. 2B).

  In this case, the integrated control device 50 may be configured to determine the setting power of the speed control for the first steam turbine 2A based on any available information. For example, the set power of the speed control for the first steam turbine 2A may be determined according to the rate of increase (the amount of increase per unit time) of the generated power of the second steam turbine 2B. Specifically, the set power may be increased as the increase rate is increased. Alternatively, the integrated control device 50 may use the value stored in advance in the attached storage medium as the setting power.

  When the setting power of the speed control is updated to a larger value, the turbine control panel 15a of the first governor mechanism 15A monitors the output of the first power sensor 8A, and the generated power of the first steam turbine 2A is newly added. The opening degree of the first steam control valve 3A is increased to maintain the set power. As a result, the power generated by the first steam turbine 2A increases as the amount of steam increases, as indicated by the black arrows in FIG. 2 (B). Due to such updating of the set power, the pressure of the steam in the steam pipe SL becomes difficult to increase compared to before updating. This is because more steam in the steam pipe SL is sent to the first steam turbine 2A. At this time, the integrated control device 50 sends the steam to the second steam turbine 2B when a trend of a drop in the steam pressure is detected so as to prevent the pressure of the steam in the steam pipe SL from decreasing in a short period of time. Make adjustments to reduce the amount automatically. In this case, the power generated by the second steam turbine 2B decreases as the amount of steam decreases.

  Thereafter, when the amount of steam generated in the boiler 1 further increases, the pressure of steam in the steam pipe SL tends to further increase. Therefore, the turbine control unit 15f of the second governor mechanism 15B monitors the output of the second steam pressure sensor 6B while maintaining the pressure of steam in the steam pipe SLB at the set pressure. Further increase the degree of opening. As a result, the power generated by the second steam turbine 2B further increases as the amount of steam increases, as indicated by the white arrows in FIG. 2 (B).

  Thereafter, when the generated power of the second steam turbine 2B reaches a second upper limit threshold (for example, 8000 [kW] indicated by a broken line in FIG. 2C) larger than the first upper limit threshold, the integrated control device 50 The set power of the speed control performed in the turbine 2A is updated again. Specifically, when the integrated control device 50 determines that the generated power of the second steam turbine 2B has reached the second upper limit threshold based on the output of the second power sensor 8B, the integrated control device 50 is executed by the first steam turbine 2A The set power of the speed control is updated to a third set value (e.g., 6000 [kW] indicated by an alternate long and short dash line in FIG. 2C) which is a larger value.

  When the set power for the speed control is thus updated to a large value, the turbine control panel 15a of the first governor mechanism 15A monitors the output of the first power sensor 8A while the generated power of the first steam turbine 2A. The opening degree of the first steam control valve 3A is further increased so as to maintain the new set power. As a result, the power generated by the first steam turbine 2A further increases as the amount of steam increases, as indicated by the black arrows in FIG. 2 (C). Such re-updating of the set power makes it more difficult for the pressure of the steam in the steam pipe SL to rise. This is because more steam in the steam pipe SL is sent to the first steam turbine 2A. At this time, the integrated control device 50 sends the steam to the second steam turbine 2B when a trend of a drop in the steam pressure is detected so as to prevent the pressure of the steam in the steam pipe SL from decreasing in a short period of time. Make adjustments to reduce the amount automatically. In this case, the power generated by the second steam turbine 2B decreases as the amount of steam decreases.

  After that, even when the amount of steam generated in the boiler 1 further increases, the integrated control device 50 similarly sets the set power for the speed control at the time when the generated power of the second steam turbine 2B exceeds the nth upper limit threshold. Such a situation can be coped with by changing the nth setting value to the n + 1th setting value. Here, n is an integer of 3 or more.

  Subsequently, a case where the amount of steam generated in the boiler 1 decreases will be described. Thereafter, as the amount of steam decreases, the pressure of steam in the steam pipe SL tends to decrease. Therefore, the turbine control unit 15f of the second governor mechanism 15B monitors the output of the second steam pressure sensor 6B while maintaining the pressure of steam in the steam pipe SLB at the set pressure. Reduce the degree of opening. As a result, the power generated by the second steam turbine 2B decreases as the amount of steam decreases, as indicated by the white arrows in FIG. 2 (D).

  Thereafter, when the generated power of the second steam turbine 2B reaches the lower limit threshold (for example, 7000 [kW] indicated by a broken line in FIG. 2E), the integrated control device 50 adjusts the regulation performed in the first steam turbine 2A. Update the setting power of the fast control again. Specifically, when the integrated control device 50 determines that the generated power of the second steam turbine 2B has reached the lower limit threshold based on the output of the second power sensor 8B, the adjustment performed in the first steam turbine 2A is performed. The set power of the speed control is updated to a smaller value (e.g., 2000 [kW] indicated by an alternate long and short dash line in FIG. 2E).

  In this case, the integrated control device 50 may be configured to determine the setting power of the speed control for the first steam turbine 2A based on any available information. For example, the set power of the speed control for the first steam turbine 2A may be determined according to the reduction rate (the reduction amount per unit time) of the generated power of the second steam turbine 2B. Specifically, the set power may be reduced as the reduction rate increases. Alternatively, the integrated control device 50 may use the value stored in advance in the attached storage medium as the setting power.

  The integrated control apparatus 50 can set a plurality of levels of thresholds as in the case of the upper limit threshold also for the lower limit threshold. For example, when the generated power of the second steam turbine 2B falls below the nth lower limit threshold, the set power of the speed control can be changed from the n + 1th set value to the nth set value. At this time, by setting the nth lower limit threshold to a value lower than the nth upper limit threshold, the plurality of governor mechanisms 15 can be stably controlled.

  When the setting power of the speed control is updated to a smaller value, the turbine control panel 15a of the first governor mechanism 15A monitors the output of the first power sensor 8A, and the generated power of the first steam turbine 2A is newly added. The opening degree of the first steam control valve 3A is reduced so as to maintain the set power. As a result, the power generated by the first steam turbine 2A decreases as the amount of steam decreases, as indicated by the black arrows in FIG. 2 (E). And the electric power generation of the 1st steam turbine 2A and the 2nd steam turbine 2B will be in a state as shown in Drawing 2 (F). Due to such updating of the set power, the pressure of the steam in the steam pipe SL is less likely to drop compared to before updating. This is because the amount of steam absorbed by the first steam turbine 2A is limited.

  Next, with reference to FIG. 3, a flow of processing (hereinafter, referred to as “integration processing”) in which the integrated control device 50 integrally controls the first governor mechanism 15A and the second governor mechanism 15B will be described. FIG. 3 is a flowchart showing an example of the integration process. For example, while the power generation system 100 is in operation, the integrated control device 50 repeatedly executes this integration process at a predetermined control cycle.

  First, the integrated control device 50 determines whether it is necessary to increase the set power of the speed control in the first steam turbine 2A (step ST1). In the present embodiment, the integrated control device 50 determines, based on the output of the second power sensor 8B, whether or not the generated power of the second steam turbine 2B operated by the pre-pressure control is larger than the threshold at the time of steam amount increase. . The threshold at the time of steam amount increase is, for example, the first upper threshold, the second upper threshold, etc. described with reference to FIG. However, it may be calculated in real time. Further, the integrated control device 50 determines whether or not the set power of the speed control is smaller than the appropriate value when the amount of steam increases. The appropriate value when the amount of steam increases is, for example, a value determined according to the increase rate of the generated power of the second steam turbine 2B, etc., and 4000 [kW] (second set value) in FIG. It is 6000 [kW] (third set value) and the like in FIG. 2 (C). However, a value registered in advance may be used. Then, when the integrated control device 50 determines that the power generated by the second steam turbine 2B is larger than the threshold at the time of steam amount increase, and the set power for the speed control is smaller than the appropriate value at the time of steam amount increase. It is determined that it is necessary to increase the set power of the speed control. In addition, the integrated control device 50 determines that the power generated by the second steam turbine 2B is equal to or less than the threshold at the time of steam amount increase, or that the set power of the speed control is at least the appropriate value at the time of steam amount increase. In this case, it is determined that it is not necessary to increase the set power of the speed control.

  When it is determined that it is necessary to increase the set power of the speed control (YES in step ST1), the integrated control device 50 increases the set power of the speed control (step ST2). The integrated control device 50, for example, increases the set power of the speed control to an appropriate value when the amount of steam increases.

  If it is determined that it is not necessary to increase the set power for the speed control (NO in step ST1), the integrated control device 50 executes the next step without increasing the set power for the speed control.

  The integrated control device 50 determines whether or not it is necessary to reduce the set power of the speed control in the first steam turbine 2A (step ST3). In the present embodiment, the integrated control device 50 determines, based on the output of the second power sensor 8B, whether or not the generated power of the second steam turbine 2B is smaller than the threshold at the time of the reduction of the steam amount. The threshold at the time of steam volume reduction is, for example, the lower limit threshold described with reference to FIG. However, it may be calculated in real time. Further, the integrated control device 50 determines whether or not the set power of the speed control is larger than the appropriate value at the time of the reduction of the steam amount. The appropriate value at the time of steam amount reduction is, for example, a value determined according to the reduction rate of the generated power of the second steam turbine 2B and the like, and is 2000 [kW] in FIG. However, a value registered in advance may be used. Then, when the integrated control device 50 determines that the generated power of the second steam turbine 2B is smaller than the threshold value at the time of steam volume reduction, and the setting power of the speed control is larger than the appropriate value at the time of steam volume reduction It is determined that it is necessary to reduce the set power of the speed control. In addition, the integrated control device 50 determines that the power generated by the second steam turbine 2B is equal to or higher than the threshold at the time of steam reduction, or that the set power of the speed control is at or below the appropriate value at the time of steam reduction. In this case, it is determined that it is not necessary to reduce the set power of the speed control.

  When it is determined that it is necessary to reduce the set power of the speed control (YES in step ST3), the integrated control device 50 reduces the set power of the speed control (step ST4). The integrated control device 50, for example, reduces the set power of the speed control to an appropriate value at the time of steam amount reduction.

  If it is determined that it is not necessary to reduce the set power for the speed control (NO in step ST3), the integrated control device 50 ends the present integration processing without reducing the set power for the speed control.

  As described above, when the generated power of the second steam turbine 2B operated by the prepressure control exceeds the threshold at the time of the increase in the amount of steam of the first steam turbine 2A operated by the speed control, as described above. Try to increase the set power. In addition, when the generated power of the second steam turbine 2B operated by the prepressure control falls below the threshold at the time of the decrease of the steam amount, the set power of the first steam turbine 2A operated by the speed control is reduced. With this configuration, the integrated control device 50 can integrally control the plurality of steam turbines 2 while maintaining the stability of the boiler system that can be realized by the prepressure control.

[Example]
Here, the case where the integrated control apparatus 50 which concerns on the above-mentioned embodiment is applied to the copper smelting plant which is an example of a nonferrous metal smelting plant is demonstrated.

  The copper smelting plant is an example of a nonferrous metal smelting plant that uses sulfide concentrate as a raw material, mainly smelting furnace equipment that melts sulfide concentrate, converter equipment that blows melted crude copper to remove impurities And a sulfuric acid plant that recovers sulfurous acid gas, which is a smelting waste gas, to produce sulfuric acid. The smelting furnace facility includes, for example, a self-burning furnace, and the converter facility includes, for example, a converter.

  Each of these facilities and plants is equipped with a waste heat recovery facility for the purpose of waste heat recovery. The waste heat recovery facility includes, for example, a self-burning furnace waste heat boiler as the first boiler 1A, a converter 1 furnace waste heat boiler as the second boiler 1B, and a converter 2 furnace waste heat as the third boiler 1C. Includes a boiler. The steam generated by heat recovery by the boiler 1 is used not only for various applications as a heating medium in the factory but also for power generation using the steam turbine 2. In a large-scale copper smelting plant, since a large amount of steam is generated in the boiler 1 and the power demand is large, generally, a plurality of steam turbines 2 are provided.

  When energy is recovered by generating power with the steam turbine 2, control associated with both the boiler 1 and the steam turbine 2 is important. For example, since power supply is the main purpose in a general power plant, the boiler 1 and the steam turbine 2 are controlled so that stable power supply can be performed. Specifically, the amount of fuel consumption and the like in the boiler 1 are controlled in accordance with the energy required by the steam turbine 2. However, in a plant in which the waste heat of the smelting waste gas is recovered by the boiler 1, the amount and temperature of the smelting waste gas fluctuate in accordance with the operation status of the smelting furnace facility. In addition, in the converter facility, since the operation of the converter is a batch type, the supply of waste heat becomes intermittent. That is, the amount of steam supplied to the steam turbine 2 fluctuates. Therefore, in the power generation system 100, unlike the control mainly aiming at the stable supply of power in the power plant as described above, the control mainly intended to process the steam generated in the boiler 1, ie, the amount of steam It is desirable that control of the combined steam turbine 2 be performed.

  In the copper smelting and refining plant, steam generated in a plurality of boilers 1 is combined and fed to the steam turbine 2. Therefore, the pressure of the steam sent to the steam turbine 2 is fluctuated only when the amount of steam generated by any one of the plurality of boilers 1 fluctuates. Therefore, in the power generation system 100, one of the steam turbines 2 is configured to execute pre-pressure control.

  However, when the steam generated by the plurality of boilers 1 is sent to the plurality of steam turbines 2 to perform the power generation operation, if the prepressure control is performed by the plurality of steam turbines 2, the control may not converge.

  Therefore, in the power generation system 100, the speed control is executed by the first steam turbine 2A, which is one of the two steam turbines 2, and by the second steam turbine 2B, which is another one of the two steam turbines 2. Pre-pressure control is configured to be performed.

  Specifically, the pressure of the steam supplied to the second steam turbine 2B in which the prepressure control is executed is provided before (upstream side) the second steam turbine 2B even when the amount of steam fluctuates. It is adjusted to match the set pressure by changing the opening degree of the second steam control valve 3B. By this pre-pressure control, the second steam turbine 2B can increase or decrease the amount of power generation according to the fluctuation of the amount of steam.

  Further, in the first steam turbine 2A in which the speed control is executed, the set power (generated power) is fixed regardless of the change in the amount of steam. The power generation system 100 can operate the first steam turbine 2A continuously by adjusting the set power according to the operation of the turbine operator or automatically. In this case, the set power may be automatically predicted from the conditions of a self-heating furnace, a converter and the like.

  The adjustment of the set power of the first steam turbine 2A is performed, for example, as follows. If the steam pressure is expected to increase in the boiler 1 or if it is actually increasing, the power generation system 100 can increase the set power of the first steam turbine 2A in the first steam turbine 2A. Energy consumption of the boiler 1 to make it difficult for the circulating water temperature of the boiler 1 to rise. This is to prevent overheating of the boiler 1 and maintain the ability to cool the smelting waste gas. On the other hand, if it is predicted that the steam pressure in the boiler 1 is lowered, or if it is actually lowered, the power generation system 100 reduces the amount of steam used in the first steam turbine 2A and circulates the boiler 1 Make the water temperature hard to lower. This is to leave behind the thermal energy used for power generation.

  In a large-scale copper smelting plant, since a large number of boilers 1 operate on each piece and fluctuations in the amount of steam frequently occur, adjustment of the set power of the first steam turbine 2A is also performed frequently. If the setting power is incorrectly adjusted, the pressure of the boiler 1 excessively increases or decreases and the safety valve 12 is actuated. The operation of the safety valve 12 causes disturbance of the boiler control system, which may hinder the stable operation of the copper smelting plant. Therefore, in the power generation system 100, typically, adjustment of the set power of the first steam turbine 2A is automatically performed. With this automatic adjustment, the power generation system 100 constantly checks the operating state (for example, the generated power) of the second steam turbine 2B for frequent fluctuations in the amount of steam, and predicts fluctuations in the amount of steam, It is possible to substitute for the complicated operation by the turbine driver such as adjusting the set power of the turbine 2A. And it becomes unnecessary to have a dedicated turbine operator of the first steam turbine 2A, and it is possible to prevent that the set power is erroneously adjusted. In particular, when different types of governor mechanisms are adopted in each of the first steam turbine 2A and the second steam turbine 2B, the response speed tends to differ between the two governor mechanisms. Therefore, in the adjustment of the setting power of the first steam turbine 2A manually, it is difficult to properly control the entire power generation system 100. However, by automatically executing the adjustment of the set power of the first steam turbine 2A, the power generation system 100 can accurately adjust the entire system even if there is a difference in response speed between the two governor mechanisms. Can be controlled.

  As described above, when power generation is performed using a plurality of steam turbines 2 in a copper smelting plant, the integrated control device 50 maintains the stability of the boiler system that can be realized by the prepressure control, even if the amount of steam fluctuates. While, the plurality of steam turbines 2 can be controlled in an integrated manner. In addition, it is possible to eliminate the need for a dedicated turbine operator and to prevent the setting power from being erroneously adjusted. Furthermore, fully automatic control of about six hours is possible.

  In the power generation system 100, from the viewpoint of changing the amount of power generation smoothly, one of the steam turbines 2 is preferably subjected to pre-pressure control, and from the viewpoint of preventing control competition, a plurality of steam turbines 2 Preferably, the speed control is performed on all or one of the steam turbines 2 except for one of them.

  As described above, the integrated control device 50 according to the embodiment of the present invention is configured to integrally control the plurality of steam turbines 2 that rotate using the steam generated by the one or more boilers 1. . Then, the integrated control device 50 is one of the plurality of steam turbines 2 and the operation state of the first steam turbine 2A for which the speed control is executed by another one of the plurality of steam turbines. It is comprised so that it may be changed according to the driving | running state of the 2nd steam turbine 2B in which some pre pressure control is performed.

  In addition, the integrated control method according to the embodiment of the present invention integrally controls a plurality of steam turbines 2 that rotate using steam generated by one or more boilers 1. Then, the integrated control method includes the step of executing the speed control in the first steam turbine 2A, which is one of the plurality of steam turbines 2, and the second one, which is another one of the plurality of steam turbines 2. The method includes the steps of executing the prepressure control in the steam turbine 2B and changing the operating state of the first steam turbine 2A according to the operating state of the second steam turbine 2B.

  With the above configuration, the integrated control device 50 can integrally control the plurality of steam turbines 2 while maintaining the stability of the boiler system that can be realized by the prepressure control.

  The steam generated by the one or more boilers 1 is typically a steam generated by a waste heat recovery boiler that recovers the waste heat generated by a batch process in a plant such as a nonferrous metal smelting plant. Further, the response speed of the first steam turbine 2A may be configured to be different from the response speed of the second steam turbine 2B. Specifically, the response speed of the first governor mechanism 15A may be configured to be different from the response speed of the second governor mechanism 15B. Also, the plurality of steam turbines 2 may include a bleed turbine.

  Hereinabove, the preferred embodiments of the present invention have been described in detail. However, the present invention is not limited to the embodiments described above. Various modifications and substitutions may be applied to the embodiment described above without departing from the scope of the present invention. Also, each of the features described with reference to the above embodiments may be combined as appropriate as long as there is no technical contradiction.

  For example, in the above embodiment, the power generation system 100 is configured to include the two steam turbines 2 of the first steam turbine 2A and the second steam turbine 2B, but includes the three steam turbines 2 May be configured. In this case, the front pressure control is applied to one of the three units, and the speed control is applied to the remaining two of the three units. It is because there is a possibility that the integrated control of the power generation system 100 may not be stabilized due to the difference in response characteristics regarding the governor mechanism, etc., if the front pressure control is applied to two or more of the three units.

  Further, in the above-described embodiment, each of the steam turbines 2 is, for example, a one-stage bleed-condensed water turbine that consumes about 20% of the degree of superheat for power generation and consumes the remaining about 80% for condensate. , At least one of the steam turbines 2 may be a multistage bleed / condensed water turbine. The steam turbine 2 may be a back pressure turbine. In this case, the back pressure turbine may be a single-stage bleed back pressure turbine or a multi-stage bleed back pressure turbine. The steam turbine 2 may have a configuration in which a plurality of steam turbines are connected in series. FIG. 4 is a view showing another configuration example of the second steam turbine 2B. As shown in FIG. 4, the second steam turbine 2 </ b> B may have a configuration in which two steam turbines are connected in series.

  In the above embodiment, the first governor mechanism 15A of the first steam turbine 2A adopts a mechanical governor mechanism, and the second governor mechanism 15B of the second steam turbine 2B adopts an electronic governor mechanism. There is. That is, two governor mechanisms 15 having different response speeds are employed. However, an electronic governor mechanism may be adopted as the first governor mechanism 15A, and a mechanical governor mechanism may be adopted as the second governor mechanism 15B. Also, two governor mechanisms 15 having equal response speeds may be employed. For example, an electronic governor mechanism may be employed for both the first governor mechanism 15A and the second governor mechanism 15B, or a mechanical governor mechanism may be employed. The mechanical governor mechanism may be a hydraulic governor mechanism.

  Further, in the above-described embodiment, the integrated control device 50 is configured such that the generated power of the second steam turbine 2B operated by the prepressure control is larger than the generated power of the first steam turbine 2A operated by the speed control. , The setting power of the speed control is updated. Specifically, in the integrated control device 50, the power generated by the first steam turbine 2A operated by the speed control is slightly smaller than the power generated by the second steam turbine 2B operated by the pressure control. As such, the set power of the speed control is updated. For example, the set power of the speed control is updated so that the generated power of the first steam turbine 2A operated by the speed control follows the generated power of the second steam turbine 2B operated by the prepressure control. Compared with the case where the power generated by the second steam turbine 2B operated by the prepressure control is smaller than the power generated by the first steam turbine 2A operated by the speed control, the pressure fluctuation of the steam in the steam pipe SL can be reduced. is there. For the same reason, the second steam turbine 2B may be configured such that its turbine rated power is greater than the turbine rated power of the first steam turbine 2A. Further, the second generator 4B connected to the second steam turbine 2B is configured such that the generator capacity thereof is larger than the generator capacity of the first generator 4A connected to the first steam turbine 2A. It may be

  DESCRIPTION OF SYMBOLS 1 ... boiler 1A ... 1st boiler 1B ... 2nd boiler 1C ... 3rd boiler 2 ... steam turbine 2A ... 1st steam turbine 2B ... 2nd steam turbine 3 ... · · Steam control valve 3A · · · 1st steam control valve 3 B · · · 2nd steam control valve 4 · · · Generator 4A · · · 1st generator 4B · · · 2nd generator 5 · · · Recovery Water cooler 5A ... 1st condenser 5B ... 2nd condenser 6 ... Steam pressure sensor 6A ... 1st steam pressure sensor 6B ... 2nd steam pressure sensor 7 ... Rotation Number sensor 7A: first rotation speed sensor 7B: second rotation speed sensor 8: power sensor 8A: first power sensor 8B: second power sensor 9: hydraulic source 10 · · Bleed air control valve 10A · · · 1st bleed air control valve 10 B · · · 2nd bleed air control valve 11 · · · Atmospheric pressure sensor 11A: first bleed pressure sensor 11B: second bleed pressure sensor 12: safety valve 12A: first safety valve 12B: second safety valve 15: governor mechanism 15A: second 1 Governor mechanism 15B ... 2nd governor mechanism 15a ... Turbine control board 15b ... Governor 15c ... Governor motor 15d ... Load limiter 15e ... Opening transmitter 15f ... Turbine control unit 15 g ··· Electro-hydraulic converter 50 ··· Integrated control device 100 ··· Power generation system

Claims (5)

An integrated control device that integrally controls a plurality of steam turbines that rotate using steam generated by one or more boilers, comprising:
One of the plurality of steam turbines, an operating state of a first steam turbine for which speed control is performed, and another pressure control, which is another one of the plurality of steam turbines, are performed Configured to change according to the operating condition of the second steam turbine,
Integrated control unit. The steam generated by the one or more boilers includes steam generated by a waste heat recovery boiler that recovers waste heat generated by a batch process in a plant.
The integrated control device according to claim 1. The response speed of the first steam turbine is different from the response speed of the second steam turbine,
The integrated control device according to claim 1. The plurality of steam turbines include a bleed turbine.
The integrated control device according to any one of claims 1 to 3. An integrated control method for integrally controlling a plurality of steam turbines that rotate using steam generated by one or more boilers, comprising:
Performing speed control on a first steam turbine that is one of the plurality of steam turbines;
Performing pre-pressure control on a second steam turbine that is another one of the plurality of steam turbines;
Changing the operating state of the first steam turbine according to the operating state of the second steam turbine.
Integrated control method.

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