PH12018000262A1 - Extraction control method for steam turbine generator and control device for the steam turbine generator - Google Patents
Extraction control method for steam turbine generator and control device for the steam turbine generator Download PDFInfo
- Publication number
- PH12018000262A1 PH12018000262A1 PH12018000262A PH12018000262A PH12018000262A1 PH 12018000262 A1 PH12018000262 A1 PH 12018000262A1 PH 12018000262 A PH12018000262 A PH 12018000262A PH 12018000262 A PH12018000262 A PH 12018000262A PH 12018000262 A1 PH12018000262 A1 PH 12018000262A1
- Authority
- PH
- Philippines
- Prior art keywords
- steam
- extraction
- amount
- generator
- turbine
- Prior art date
Links
- 238000000605 extraction Methods 0.000 title claims abstract description 219
- 238000000034 method Methods 0.000 title claims abstract description 35
- 230000001360 synchronised effect Effects 0.000 claims description 4
- 230000001105 regulatory effect Effects 0.000 description 17
- 230000001276 controlling effect Effects 0.000 description 7
- 239000000284 extract Substances 0.000 description 5
- 238000011144 upstream manufacturing Methods 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- RLQJEEJISHYWON-UHFFFAOYSA-N flonicamid Chemical compound FC(F)(F)C1=CC=NC=C1C(=O)NCC#N RLQJEEJISHYWON-UHFFFAOYSA-N 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 230000004044 response Effects 0.000 description 2
- 238000004326 stimulated echo acquisition mode for imaging Methods 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- 230000010485 coping Effects 0.000 description 1
- 230000002542 deteriorative effect Effects 0.000 description 1
- 210000004035 fr. d Anatomy 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 239000000377 silicon dioxide Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Control Of Turbines (AREA)
Abstract
Proposed is an extraction control method for a steam turbine generator which can appropriately cope with a fluctuation in amount of extraction steam caused by adhesion of scale to a turbine, the lowering of the degree of vacuum in a condenser or the like. In the steam turbine generator including a steam flowmeter at an extraction outlet of the steam turbine and an automatically-controlled relief valve in an extraction line, an approximation formula obtained from a relation between a generator output and the amount of extraction steam is not directly programmed, but the generator output and the amount of extraction steam are inputted as parameters so as to enable respective approximate vertexes and gradients to be varied.
Description
8 en ©
[0008]
That is, when a factory is completely stopped so that heating, heat retention, or the like performed by 5 steam is not necessary, the turbine generator is operated i in the region A where extraction is unnecessary. When - the factory is in operation, extraction steam is used as steam for heating, heat retention, or the like so that " the turbine generator is operated in the region B or more. 2
When a power load of the factory is high, the turbine = generator is operated in a region C. Further, when the amount of extraction steam becomes larger than the amount of steam to be used in a factory, surplus steam is released into the atmosphere. When the turbine generator is operated while a generator output exceeds the region A, a fixed flow rate or greater of inlet steam is necessary to maintain a generator output.
The "region B" is also a region where the flow rate of inlet steam increases corresponding to a generator output, but the amount of extraction steam to be supplied is fixed so that existing extraction control is unstable.
Further, the "region C" is also a region where the flow rate of inlet steam increases corresponding to a generator output, and the amount of extraction steam also increases in a corresponding manner so that it is necessary to increase the amount of extraction steam corresponding to a generator output. A difference between a dotted line and a solid line in the graph indicates the amount of extraction steam.
9 je fo
[0009] o
In order to increase a generator output, in the z region A, even if the flow rate of inlet steam is © increased, power can be generated at the amount of we extraction steam of 0 T/Hr. In order to increase the = output to the region B, C, or more, the flow rate of -
RN inlet steam exceeds a capacity of the condenser. Hence, - it is necessary to increase the amount of extraction = steam. A left end of the region A indicates a minimum i» capacity of the generator, and a right end of the region
C indicates a maximum capacity of the generator.
[0010]
Accordingly, a relief valve is provided for releasing surplus steam into the atmosphere when the amount of extraction steam required for maintaining this generator output exceeds the amount of extraction steam to be used in a factory. In the region B and the region c, when the generator output fluctuates with a fluctuation in amount of power to be used in a factory, or when the amount of steam to be supplied to a factory or the amount of extraction steam fluctuates with a fluctuation in amount of extraction steam to be used in the factory, the relief valve is opened or closed to maintain the amount of extraction steam required for maintaining a generator output.
[0011]
According to the extraction control method for a steam turbine generator, the automatically-controlled
10 i. bi relief valve installed on the extraction line can be oo automatically controlled in an independent manner based = [ on an appropriate amount of extraction steam which = corresponds to a generator load. Thus, it is possible to wo reduce an excessively large amount of extraction steam to = be released into the atmosphere and to maintain a stable . generator output even when a generator load or the amount ~ of extraction steam to be used in a factory unexpectedly © and rapidly fluctuates. Further, the steam flowmeter and - the automatically-controlled relief valve installed on the extraction line can be easily and additionally installed on an existing turbine generator control device without applying any change to the existing turbine generator control device. Therefore, it is possible to acquire an excellent effect that there is no possibility of equipment cost becoming high.
[0012]
However, the extraction control method for a steam turbine generator has the following problems.
That 1s, in the turbine generator which extracts steam from an intermediate stage of the steam turbine, and supplies the steam to a factory, the amount of extraction steam with respect to a generator output is determined by characteristics of the turbine so that a relief valve can be automatically controlled using an approximation formula obtained from a relation between the generator output and the amount of extraction steam.
However, steam to be supplied to the turbine contains
& impurities such as silica or chloride ion, or a das. on
Hence, when adhesion of scale to a turbine, the lowering - of the degree of vacuum in a condenser or the like causes < a capacity of a condenser to lower thus deteriorating a we release of steam to the discharge side, it becomes =o necessary to increase the amount of extraction steam to - maintain a generator output of the turbine. When the - operation of the steam turbine generator is continued = while the relief valve is automatically controlled using the approximation formula in such a situation, there is a possibility that a set value of the amount of extraction steam obtained as a result of the calculation lowers the actual amount of extraction steam so that the amount of steam being released into the atmosphere becomes insufficient, thus increasing the pressure of extraction steam and causing insufficient amount of extraction steam.
Hence, a generator output cannot be maintained. To prevent such a phenomenon, it 1s necessary to review a programmed calculation expression, and to rewrite the calculation expression while automatic control of the relief valve is stopped. Further, in a factory having a plurality of turbines, it is necessary to determine an approximation formula according to characteristics of each turbine, and program a different calculation expression for each turbine.
Patent Literature
[0013]
Patent Literature 1: Japanese Patent Application Laid- :
Open No. HO7-166808 ©
Patent Literature 2: Japanese Patent Application Laid- fo
Open No. H11-343814 -
[0014]
The present invention has been made to solve the above-mentioned problems of the conventional art, and it is an object of the present invention to propose an extraction control method for a steam turbine generator and a control device for the steam turbine generator where an approximation formula obtained from a relation between a generator output and the amount of extraction steam 1s not directly programmed, but the generator output and the amount of extraction steam are inputted as parameters so as to enable a starting point and a gradient of an approximate polygonal line to be varied.
Hence, it 1s possible to appropriately cope with a fluctuation in amount of extraction steam caused by adhesion of scale to a turbine, the lowering of the degree of vacuum in a condenser or the like.
Solution to Problems
13 pea]
Wo
The present invention is directed to an extraction = control method for a steam turbine generator configured = [Ee to extract steam from an intermediate stage of a steam = turbine and to supply the steam to a factory, the steam he turbine generator including a steam flowmeter at an = extraction outlet of the steam turbine, an automatically- ” controlled relief valve in an extraction line, and a ~ calculation and control device for obtaining a set value © of an amount of extraction steam which corresponds to a - generator output to control the relief valve, the method including, in automatically controlling the relief valve by an amount of the extraction steam determined by a characteristic of the steam turbine: setting respective vertexes and gradients of a variable polygonal line based on a relation between the generator output and the amount of the extraction steam, as parameters; obtaining a set value of an amount of the extraction steam which corresponds to a generator output by calculation based on a characteristic of the parameters; and independently controlling surplus steam using the relief valve based on the set value and a set amount of steam to be used in a factory.
In the extraction control method according to the present invention, intersection of the generator output and the amount of the extraction steam, defining respective vertexes of the variable polygonal line according to the characteristic of the steam turbine, is preferably set as the parameter at a plurality of points.
14 0
The present invention is also directed to an = extraction control device for a steam turbine generator - including: an equipment unit which includes: an © extraction line configured to extract steam from an we extraction outlet provided at an intermediate stage of a = steam turbine, and to supply the steam to a factory; a ” steam flowmeter installed on the extraction line; and an ~ automatically-controlled relief valve equipped with a =z controller configured to discharge the steam extracted to = an atmosphere, the relief valve being provided on a line branched from the extraction line on a side closer to the factory than the steam flowmeter installed on the extraction line; and a calculation and control device which includes: an input part configured to receive a generator output transmitted from the steam turbine generator and an amount of steam to be used in the factory transmitted from the factory as inputs; a database region configured to store "coordinates of vertexes each of which is defined by intersection of a generator output and an amount of extraction steam" and "gradients between the vertexes disposed adjacent to each other", which are obtained in advance, as parameters, the coordinates of the vertexes defining respective vertexes of a variable polygonal line according to a characteristic of the steam turbine; a calculation unit configured to generate and output a command signal for controlling the relief valve based on a set value of the amount of the extraction steam, which is obtained from
15 oo the parameters corresponding to the generator output and - the amount of steam to be used in the factory: an output - part configured to output the command signal outputted = from the calculation unit to a controller for the relief we valve; and an operation data region configured to store = the generator output, the amount of steam to be used in ol the factory, the set value, and the command signal in a I synchronized manner. =
[0016]
According to the extraction control method for a steam turbine generator and the control device for the steam turbine generator of the present invention, an approximation formula obtained from a relation between the generator output and the amount of extraction steam is not directly programmed, but the generator output and the amount of extraction steam are inputted as parameters so as to enable the respective approximate vertexes and gradients to be varied. Accordingly, even when the amount of extraction steam is increased due to lowering of a capacity of the condenser which is caused by adhesion of scale to a turbine, the lowering of the degree of vacuum in a condenser or the like, without reviewing and rewriting the programmed calculation expression while automatic control of the relief valve is stopped, changing control characteristics of the relief valve to correct an increase in pressure of extraction
16 { [EN] steam caused by insufficient amount of steam being os
Foot released into the atmosphere and an insufficient amount = of extraction steam allows a stable generator output to = be maintained. wo
[0017]
Further, also in a factory having a plurality of w steam turbines, it is sufficient to change only _ parameters while the same calculation expression is used, = without determining an approximation formula according to - characteristics of each turbine and a different calculation expression is programmed for each turbine.
[0018]
FIG. 1 is a schematic view showing a system configuration example for carrying out an extraction control method for a steam turbine generator according to the present invention;
FIG. 2 is a flowchart showing the extraction control method for a steam turbine generator of the present invention in the system configuration example shown in
FIG. 1;
FIG. 3 is an explanatory view showing a setting example of an amount of extraction steam with respect to a generator output of the present invention in the system configuration example shown in FIG. 1;
CE
17 om
FIG. 4 is a schematic view showing a configuration example of an extraction control device for the steam ~ turbine generator of the present invention; ©
FIG. 5 is a schematic view showing a system ~ configuration example of a conventional internal = extraction pressure control type turbine generator; Hr
FIG. 6 is an explanatory view showing a conventional _ setting example of a generator output and an amount of © extraction steam; and ol
FIG. 7 is an explanatory view showing the relation between a conventional generator output, a flow rate of inlet steam, and an amount of extraction steam.
[0019]
The system configuration for carrying out an extraction control method for a steam turbine generator according to the present invention as shown FIG. 1 includes: an extraction turbine type steam turbine 1 which converts a thermal energy of steam introduced from a superheated steam producing boiler (not shown) into a drive energy; a steam regulating valve 2 which adjusts a flow rate of steam to be introduced through a steam introducing port 2-1; an extraction regulating valve 3; an extraction pressure gauge 4; a speed indicator 5; a speed governor 6; a condenser 7; an extraction line 8; a steam flowmeter 9 installed at an extraction outlet of the steam turbine 1; a calculation and control device 10; da
18 CE and an automatically-controlled relief valve (adjusting valve) 12 equipped with a controller.
Also in the system ~ configuration according to the present invention, the = steam turbine 1 has a high pressure stage 1-1 and a low pressure stage 1-2. Steam which flows into the high > pressure stage 1-1 is extracted on the upstream side of o the extraction regulating valve 3, that 1s, on an - intermediate stage of the turbine 1, a flow of steam into = the low pressure stage 1-2 is controlled by the .
extraction regulating valve 3, and steam is then supplied to a factory through the extraction line 8 provided in the intermediate stage of the turbine 1. In the system configuration example, the configurations of constitutional elements other than the steam flowmeter 9,
the calculation and control device 10, and the automatically-controlled relief valve 12 equipped with the controller are substantially equal to the configurations of corresponding constitutional elements in the conventional art shown in FIG. 5. In the system configuration according to the present invention, a steam flowmeter and a relief valve which allows a sufficient amount of steam to flow therethrough are used for the steam flowmeter 9 and the relief valve 12 equipped with the controller.
In measuring a flow rate of steam at the turbine extraction outlet, the difference between a flow rate of steam at the turbine inlet and a flow rate of water at an outlet of the condenser 7 which is used for treating turbine exhaust may also be used.
19 0
[0020] _
The system configuration example of this steam = od turbine generator is a system where the amount of = extraction steam is set with respect to an indication of we the steam flowmeter 9 for measuring the amount of o extraction steam installed at the extraction outlet of » i the steam turbine 1 thus adjusting an opening of the - relief valve 12. When extraction steam is supplied to a = factory, the sum of the set amount of extraction steam to - be used in the factory and the amount of steam being released into the atmosphere becomes the amount of extraction steam. Accordingly, when the set amount of extraction steam to be used in the factory exceeds the amount of extraction steam, an opening of the relief valve 12 is closed. On the other hand, when the set amount of extraction steam to be used in the factory is lower than the amount of extraction steam, an opening of the relief valve 12 is opened to release surplus steam into the atmosphere thus maintaining the amount of extraction steam. The relief valve 12 is automatically controlled as described above.
[0021]
In the system configuration example of this steam turbine generator, in the case where the relief valve 12 is automatically controlled by the amount of extraction steam, which is determined by characteristics of the steam turbine 1, in a turbine generator which extracts steam from the intermediate stage of the steam turbine 1
© and supplies the steam to a factory, when the amount of oo extraction steam is increased due to adhesion of scale to = the steam turbine 1, the lowering of the degree of vacuum > in the condenser 7 or the like, it is necessary to change Re control characteristics of the relief valve 12. The = present invention employs means described hereinafter in order to cope with these fluctuations. -
That is, an approximation formula obtained from a 2 relation between the generator output and the amount of o extraction steam is not directly programmed, but the generator output and the amount of extraction steam are inputted as parameters, and respective vertexes and gradients of an approximate polygonal line are varied.
To be more specific, for example, as shown in FIG. 3, the intersection of the generator output and the amount of extraction steam, defining respective vertexes of a polygonal line, is set as parameters at ten points from
P1 to P10 according to characteristics of the steam turbine 1. An actual generator output is sequentially compared with generator outputs set at the points Pl to
P10 until a corresponding zone is found. After the corresponding zone is found, a value at a point of intersection with a line segment which connects two points is calculated as the amount of extraction steam, and the result of calculation is outputted as a set value for extraction steam amount control for controlling the relief valve 12. For example, when an actual generator output falls between the point P7 and the point P8, a
21 Li value A at a point of intersection with a line segment — having a start point at the point P7 and an end point at - the point P8 is outputted as a set value for extraction © steam amount control as the amount of extraction steam. we
Surplus steam can be controlled in an independent manner = by the relief valve 12 based on the set value and the set s amount of steam to be used in a factory. ~
[0022] =
The extraction control method for this steam turbine =” generator is described based on a flowchart shown in FIG. 2. First of all, parameters are set based on a relation between the generator output and the amount of extraction steam. Next, based on the parameter characteristics, a set value of the amount of extraction steam which corresponds to a generator output is obtained, and the set amount of extraction steam and the set amount of steam to be used in a factory are compared with each other. As a result, when the set amount of extraction steam is larger than the set amount of steam to be used in a factory, the opening of the relief valve 12 is opened. On the other hand, when the set amount of extraction steam is smaller than the set amount of steam to be used in a factory, the opening of the relief valve 12 is closed. Such calculations and comparisons are continuously performed. Hence, even if parameters are changed, control characteristics of the relief valve, such as respective starting points and gradients of a
© polygonal line, can be corrected without stopping control oo of the relief valve. iN
[0023] o
FIG. 4 is a schematic view showing an example of an we extraction control device for a steam turbine generator = for executing the above-described extraction control . method for a steam turbine generator according to the - present invention. o
In FIG. 4, reference numeral 100 denotes the o extraction control device (range surrounded by a chain line), reference character 1A denotes an extraction outlet, reference numeral 10 denotes a calculation and control device of the extraction control device, reference character 12a denotes a controller for the relief valve 12, reference numeral 101 denotes an input part, reference numeral 102 denotes an output part, reference numeral 103 denotes a calculation unit, reference numeral 104 denotes a database region, reference numeral 105 denotes operation data region, reference character EQ denotes an equipment unit of the extraction control device, reference character S denotes a command signal, reference character P denotes a generator output, reference character U denotes the amount of steam to be used in a factory, and reference character T denotes a set value of the amount of extraction steam.
23 al
Lo
The extraction control device 100 according to the present invention includes the equipment unit (EQ) formed ~ of: the extraction line (steam supply pipe) 8 which © extracts steam from the extraction outlet 1A provided at the intermediate stage of the steam turbine, and supplies = the steam to a factory therethrough; the steam flowmeter on 9 installed on the extraction line 8; and the ~ automatically-controlled relief valve 12 equipped with a = controller which is provided on a line branched from the 0 extraction line 8 on a side closer to the factory than the steam flowmeter 9 installed on the extraction line 8, and which discharges extracted steam to the atmosphere.
The extraction control device 100 causes the relief valve 12 equipped with a controller to operate in response to a command signal S from the calculation and control device (10) thus maintaining a stable generator output.
[0025]
The calculation and control device 10 according to the present invention includes: the input part 101 configured to receive a generator output transmitted from the steam turbine generator and the amount of steam to be used in the factory transmitted from the factory as inputs; the database region 104 configured to store "coordinates of vertexes each of which is defined by the intersection of a generator output and the amount of extraction steam" and "gradients between vertexes disposed adjacent to each other", which are obtained in advance, as parameters, the coordinates of the vertexes
24 I. © defining respective vertexes of a polygonal line which is =o variable according to characteristics of the steam - turbine; the calculation unit 103 configured to compare a > set value of the amount of extraction steam T, which is wo obtained from the parameter corresponding to the - generator output and an inputted amount of steam to be . used in a factory U with each other to generate a command - signal S for controlling an opening/closing operation of © the relief valve 12, and to output the command signal S; = the output part 102 configured to output the command signal S outputted from the calculation unit 103 to the controller 12a for the relief valve 12; and the operation data region 105 configured to store the generator output
P, the amount of steam to be used in a factory U, the set value of the amount of extraction steam T, and the command signal S in a synchronized manner.
[0026]
In the extraction control device 100 according to the present invention, along the extraction control method for a steam turbine generator according to the present invention shown in a flowchart in FIG. 2, based on a measured and inputted generator output P, a set value of the amount of extraction steam T is calculated from a parameter stored in the database region 104 of the calculation and control device 10. Based on a result of comparison between the set value T and the amount of steam to be used in a factory U which is synchronized with the generator output P, a command signal S which is
25 Ea a command for opening/closing the relief valve 12 is
Fo transmitted to the controller 12a, and the relief valve = 12 is operated in response to the opening/closing command. =
[0027]
As described above, in the extraction control method 5 for a steam turbine generator and the control device for 7 the steam turbine generator according to the present = invention, an approximation formula obtained from a © relation between the generator output and the amount of ol extraction steam is not directly programmed, but the generator output and the amount of extraction steam are inputted as parameters so as to enable the starting point and the gradient of the approximate polygonal line to be varied. Hence, it is possible to appropriately cope with a fluctuation in amount of extraction steam caused by adhesion of scale to a turbine, the lowering of the degree of vacuum in a condenser or the like.
Reference Signs List
[0028] 1 steam turbine 1A extraction outlet 1-1 high pressure stage 1-2 low pressure stage 2 steam regulating valve 2-1 steam introducing port 3 extraction regulating valve 4 extraction pressure gauge
26 0 speed indicator _ 6 speed governor N [ 7 condenser = 8 extraction line 5 9 steam flowmeter - calculation and control device . 12 relief valve ~ 12a controller for relief valve © 100 extraction control device oO 10 101 input part 102 output part 103 calculation unit 104 database region 105 operation data region
EQ equipment unit of extraction control device
S command signal p generator output
U amount of steam to be used in factory
T set value of amount of extraction steam of pup 1 -
Ter or or oT DESCRIPTION = . os -
EXTRACTION CONTROL METHOD FOR STEAM TURBINE GENERATOR AND =
CONTROL DEVICE FOR THE STEAM TURBINE GENERATOR hs
[0001]
The present invention relates to an extraction = control method for a steam turbine generator which extracts steam from an intermediate stage of a turbine and supplies the Steam to a factory, and more specifically to an extraction control method for a steam turbine generator and a control device for the steam turbine generator which can, in a method of automatically controlling a relief valve by the amount of extraction steam required for maintaining a generator output which is determined by characteristics of the turbine, not only appropriately cope with fluctuation in generator load and in amount of extraction steam but also appropriately cope with fluctuation in amount of extraction steam which is caused by adhesion of scale to the turbine, the lowering of the degree of vacuum in a condenser or the like.
[0002]
For steam turbine generators which extract steam from an intermediate stage of a turbine and supply the steam to a factory, an internal extraction pressure control type turbine generator is known where a pressure _ control valve is provided in the inside of a casing of - the turbine, and a pressure control is performed on the > upstream side of the pressure control valve so as to i maintain a constant extraction pressure thereby allowing o a stable pressure supply at every turbine load level from . a low load to the rated load. The internal extraction - pressure control type turbine generator is composed of: ® an extraction turbine type steam turbine 21 which o converts a thermal energy of steam introduced from a boiler for producing superheated steam (not shown in the drawing) into a drive energy; a steam regulating valve 22 which adjusts a flow rate of steam to be introduced through a steam introducing port 22-1; an extraction regulating valve 23; an extraction pressure gauge 24; a speed indicator 25; a speed governor 26; a condenser 27; and a relief valve 28, as this system configuration example is shown in FIG. 5. The steam turbine 21 has a high pressure stage 21-1 and a low pressure stage 21-2.
Steam which flows into the high pressure stage 21-1 of the steam turbine 21 is extracted on the upstream side of the extraction regulating valve 23, a flow of steam into the low pressure stage 21-2 is controlled by the extraction regulating valve 23, and the steam is then supplied to a factory through an extraction line 29.
[0003]
In controlling the extraction turbine type steam turbine 21 in the internal extraction pressure control
3 i. © type turbine generator, a revolution speed measured by o the speed indicator 25 and an extraction pressure measured by the extraction pressure gauge 24 are required. >
When a load on the steam turbine 21 or a required amount o of extraction fluctuates, it is necessary to control the - limit of the steam regulating valve 22 and the limit of . the extraction regulating valve 23. For this reason, the - internal extraction pressure control type turbine o generator has a mechanism which automatically controls = both valves of the steam regulating valve 22 and the extraction regulating valve 23 to maintain a revolution speed of the steam turbine 21, a generator output and extraction.
[0004]
A manual valve or an automatically-controlled adjusting valve is used for the relief valve 28. When the manual valve is used for the relief valve 28, the relief valve 28 is controlled to a valve opening with an allowance in advance roughly corresponding to a generator load and a flow rate of inlet steam. On the other hand, for a method where the automatically-controlled adjusting valve is used, a method is disclosed in Patent Literature 1 and Patent Literature 2 where an adjusting valve for releasing steam into the atmosphere is installed to an extraction line and, when an extraction pressure becomes a set pressure or more, an opening of the adjusting valve is automatically controlled by the extraction pressure.
The method disclosed in Patent Literature 1 is a control method where, in a steam turbine control device formed of z a speed control device or a load control device and an N extraction control device, when an extraction regulating = valve becomes a fully opened state or a minimum opening, - or when an adjusting valve becomes a fully opened state, Zn a speed control or a load control is excluded from the - control, and an extraction control is performed in = preference to other controls. Further, the method = disclosed in Patent Literature 2 is a method where, in a = boiler turbine generator where an extraction steam - passage includes: a turbine bypass pipe through which surplus steam 1s released to the condenser side; and a load control device which controls boiler steam to be introduced into a steam turbine corresponding to a generator load, the surplus steam is constantly released to the condenser from the extraction steam passage by the turbine bypass pipe through which the surplus steam is released to the condenser side, an input signal of a bypass device which controls a bypass amount of the bypass pipe 1s transmitted from the extraction steam passage, and a control of an amount of bypass steam which corresponds to load fluctuation is performed in preference to a load control device.
[0005]
However, the above-mentioned conventional extraction control technique for the steam turbine generator has been the following problems.
Je]
Li
In the steam turbine generator which extracted steam from the intermediate stage of the turbine and supplies oO fr. d the steam to a factory, when a manual valve was used for = the relief valve provided for coping with the fluctuation we 5 in generator load and amount of extraction steam to be o used in a factory, the relief valve was adjusted to an . opening with an allowance in advance roughly ~ corresponding to a generator load and a flow rate of = inlet steam and therefore an excessively large amount of = steam was released into the atmosphere. In addition, the manual valve might not cope with an unexpected rapid fluctuate in generator load or amount of extraction steam to be used in a factory.
On the other hand, in the method where the relief valve was replaced with an automatically-controlled adjusting valve disclosed in Patent Literatures 1 and 2 so that the adjusting valve was controlled by an extraction pressure, the extraction pressure fluctuated due to opening and closing of the relief valve.
Accordingly, the control of a steam regulating valve, an extraction regulating valve and the like, which were controlled by the extraction pressure in the same manner, was affected and hence, there has been a problem that a stable control of these valves could not be performed.
[0006]
In order to solve these problems of the conventional art, there is a conventional extraction control method for a steam turbine generator where a relief valve is
6 pen
Li automatically controlled in an independent manner based - on an appropriate amount of extraction steam which wo
Fo corresponds to a generator load and hence, it is possible = to reduce an excessively large amount of extraction steam wo to be released into the atmosphere and, even when a o generator load or an amount of extraction steam to be . used in a factory unexpectedly and rapidly fluctuates, a ~ stable generator output can be maintained. ©
The extraction control method for a steam turbine o generator is configured to extract steam from an intermediate stage of a steam turbine and to supply the steam to a factory, the steam turbine generator including a steam flowmeter at an extraction outlet of the steam turbine and an automatically-controlled relief valve in an extraction line, wherein a set value of an amount of extraction steam which corresponds to a generator load is obtained by calculation based on characteristics of a flow rate of inlet steam and an amount of extraction steam with respect to a generator output of the steam turbine generator, and surplus steam is independently controlled by the relief valve based on the set value.
Further, in the extraction control method for a steam turbine generator, it is a method where, based on a relation between the generator output and the set value of the amount of extraction steam shown in FIG. 6, a region where extraction is unnecessary (region A), a region where an existing extraction control is unstable (region B), and a region where an amount of extraction
7 = steam is required to increase corresponding to a turbine =o output (region C) are set, and the required amount of - i extraction steam is set to 0 T/Hr in the region where the © extraction is unnecessary (region A), a constant exhaust io amount is set in the region where the existing extraction = control is unstable (region B), and the amount of extraction steam is set to be proportional to a generator - load in the region where the amount of extraction steam © is required to increase corresponding to the turbine - output (region C).
[0007]
FIG. 7 is a graph illustrating the relation between a generator output, the flow rate of inlet steam, and the amount of extraction steam in the above-mentioned internal extraction pressure control type turbine generator, and "region A" is a region where increasing the flow rate of inlet steam allows a generator output to be outputted even if the amount of extraction steam is 0
T/Hr. However, if the flow rate of inlet steam is increased to exceed a level of the capacity of a condenser, extraction becomes necessary. When the generator output exceeds the region A, the flow rate of inlet steam exceeds the capacity of the condenser. Hence, a required generator output cannot be outputted without performing extraction. Accordingly, when the generator output shifts from the region A to a region B, it becomes necessary to rapidly carry out extraction causing a line of the amount of extraction steam to be discontinuous.
Claims (3)
1. An extraction control method for a steam turbine > generator configured to extract steam from an fe intermediate stage of a steam turbine and to supply the = steam to a factory, the steam turbine generator including a steam flowmeter at an extraction outlet of the steam - turbine, an automatically-controlled relief valve in an @ extraction line, and a calculation and control device for > obtaining a set value of an amount of extraction steam which corresponds to a generator output to control the relief valve, the method comprising, in automatically controlling the relief valve by an amount of the extraction steam determined by a characteristic of the steam turbine: setting respective vertexes and gradients of a variable polygonal line based on a relation between the generator output and the amount of the extraction steam, as parameters; obtaining a set value of an amount of the extraction steam which corresponds to a generator output by calculation based on a characteristic of the parameters; and independently controlling surplus steam using the relief valve based on the set value and a set amount of steam to be used in a factory.
28 ja
2. The extraction control method for a steam turbine — generator according to claim 1, wherein intersection of - fo the generator output and the amount of the extraction - steam, defining respective vertexes of the variable polygonal line according to the characteristic of the = steam turbine, is set as the parameter at a plurality of WI i points. om
3. An extraction control device for a steam turbine o generator comprising: an equipment unit which includes: an extraction line (steam supply pipe) configured to extract steam from an extraction outlet provided at an intermediate stage of a steam turbine, and to supply the steam to a factory; a steam flowmeter installed on the extraction line; and an automatically-controlled relief valve equipped with a controller configured to discharge the steam extracted to an atmosphere, the relief valve being provided on a line branched from the extraction line on a side closer to the factory than the steam flowmeter installed on the extraction line; and a calculation and control device which includes: an input part configured to receive a generator output transmitted from the steam turbine generator and an amount of steam to be used in the factory transmitted to the factory as inputs;
29 Bex a database region configured to store "coordinates — of vertexes each of which is defined by intersection of a < generator output and an amount of extraction steam” and = "gradients between the vertexes disposed adjacent to each we other", which are obtained in advance, as parameters, the = coordinates of the vertexes defining respective vertexes . gn of a variable polygonal line according to a - characteristic of the steam turbine; = a calculation unit configured to generate and 0 output a command signal for controlling the relief valve based on a set value of the amount of the extraction steam, which is obtained from the parameters corresponding to the generator output and the amount of steam to be used in the factory: an output part configured to output the command signal outputted from the calculation unit to a controller for the relief valve; and an operation data region configured to store the generator output, the amount of steam to be used in the factory, the set value, and the command signal in a synchronized manner.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2017174027A JP6684453B2 (en) | 2017-09-11 | 2017-09-11 | Extraction control method and control device for steam turbine generator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| PH12018000262A1 true PH12018000262A1 (en) | 2019-04-15 |
Family
ID=65904979
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PH12018000262A PH12018000262A1 (en) | 2017-09-11 | 2018-09-11 | Extraction control method for steam turbine generator and control device for the steam turbine generator |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JP6684453B2 (en) |
| PH (1) | PH12018000262A1 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111854862B (en) * | 2019-04-26 | 2021-07-02 | 中国石油天然气股份有限公司 | Turbine flowmeter flow metering correction system for natural gas |
| CN111854859B (en) * | 2019-04-26 | 2021-07-02 | 中国石油天然气股份有限公司 | Turbine flowmeter flow metering correction method for natural gas |
| CN114396327B (en) * | 2021-12-09 | 2023-06-13 | 广西电网有限责任公司电力科学研究院 | Method for adjusting power grid frequency by steam extraction of steam turbine |
-
2017
- 2017-09-11 JP JP2017174027A patent/JP6684453B2/en active Active
-
2018
- 2018-09-11 PH PH12018000262A patent/PH12018000262A1/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| JP6684453B2 (en) | 2020-04-22 |
| JP2019049234A (en) | 2019-03-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5916043B2 (en) | Method and apparatus for controlling a moisture separator reheater | |
| PH12018000262A1 (en) | Extraction control method for steam turbine generator and control device for the steam turbine generator | |
| US8510013B2 (en) | Gas turbine shutdown | |
| US20110270451A1 (en) | Control device for exhaust heat recovery system | |
| EP0195326A1 (en) | A protection-driving method of a feedwater heater and the device thereof | |
| US10060297B2 (en) | Apparatus and method for reactor power control of steam turbine power generation system | |
| EP2599971B1 (en) | Steam generation systems and methods for controlling operation of the same | |
| KR101908200B1 (en) | 2-axis type gas turbine having steam injecting apparatus | |
| CN103791485A (en) | Optimal control method of water supply system of thermal power generating unit | |
| NO155851B (en) | PROCEDURE AND DEVICE FOR CONTROL OF A STEAM TURBINE. | |
| CN111123770B (en) | Method and device for determining opening of bypass model under FCB working condition | |
| US20150184552A1 (en) | Controlling apparatus and starting method | |
| CA2588879C (en) | Steam turbine plant | |
| CN110219768B (en) | Method and device for controlling excess pressure energy recycling power generation excess flow of circulating water system | |
| CN107178779B (en) | The control method of Variable Speed Feedwater Pumps variable-speed operation | |
| CN111396855B (en) | Grading control and operation method for power station unit No. 0 high under multi-working-condition operation | |
| CN216381530U (en) | Device for expanding a fluid | |
| CN106762774B (en) | The control method of multi-stage centrifugal air compressor constant pressure air feeding | |
| CN113803121B (en) | Automatic control method and system for low-pressure steam turbine and power generation system | |
| US11125166B2 (en) | Control system, gas turbine, power generation plant, and method of controlling fuel temperature | |
| PH12018000172A1 (en) | Extraction control method for steam turbine generator | |
| JPS6239653B2 (en) | ||
| CN210688183U (en) | Water supply system and nuclear power plant | |
| CN112882512A (en) | Cylinder cooling device and method based on DCS control | |
| JPH0454204A (en) | Control device for gas-extraction and condensation type turbine |