CN113864013B - Cold end optimization method for all-condition of wet-cooling thermal power unit - Google Patents
Cold end optimization method for all-condition of wet-cooling thermal power unit Download PDFInfo
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Abstract
The invention discloses a cold end optimization method under all working conditions of a wet-cold thermal power unit, which comprises the following steps of (1) influencing the heat load of a condenser by heat supply steam extraction; (2) circulating water flow versus power; (3) calculating variable working conditions of the condenser; (4) calculating the micro-increment force; (5) optimal vacuum of the condenser; at the unit electric load P and the heat supply x 1 ,x 2 ,...,x n Inlet temperature t of circulating cooling water w1 Under certain conditions, the circulating water flow D is changed through the running mode of the circulating water pump w The maximum value F (P, x) 1 ,x 2 ,...,x n ,D w ,t w1 ) max At this time, the pressure P corresponds to the condenser pressure s The condenser is the optimal vacuum, and the corresponding operation mode of the circulating water pump is the optimal operation mode of the circulating water pump. The invention is convenient for simultaneously considering the pure condensation working condition and the heat supply working condition of the unit, reduces errors and reduces the condition of reduced economy of the unit.
Description
Technical Field
The invention relates to the technical field of wet-cold thermal power units, in particular to a cold end optimization method for all-condition of a wet-cold thermal power unit.
Background
The cold end system of the wet cooling thermal power unit steam turbine mainly comprises a steam turbine 1, a generator 2, a cooling tower 3, a condenser 4, an air extractor 5, a condensate pump 6 and a circulating water pump 7, wherein the system flow is shown in figure 1; the vacuum of the steam turbine is an important index for influencing the economy of the thermal power unit, and the circulating water pump is an important adjustable factor for changing the vacuum of the steam turbine of the wet cooling unit, so that the reasonable selection of the operation mode of the circulating water pump has important significance for the economic performance of a power plant.
The purpose of the cold end optimization is to determine the optimal operation mode of the circulating water pump of the unit under the conditions of different loads and different circulating water inlet temperatures, so that the condenser of the unit achieves optimal vacuum. In the prior art, when the unit load and the cooling water inlet temperature are fixed, the condenser vacuum changes along with the cooling water flow, and the change of the cooling water flow directly influences the power consumption of the circulating water pump. When the difference between the micro-increment power of the unit and the increment power of the circulating water pump caused by the vacuum change reaches the maximum, namely the maximum net gain power, the cooling water flow is called the optimal cooling water flow. At this time, the operation pressure of the condenser is the optimal operation vacuum, and the corresponding operation mode of the circulating water pump is the optimal operation mode of the circulating water pump.
At present, the existing cold end optimization technology: when the vacuum of the condenser is changed, a unit micro-power-increasing curve is mainly determined through a field test or a turbine plant correction curve, the field test method is to obtain a unit electric power change curve through adjusting the back pressure of the condenser under different electric loads, and the method is affected by field conditions and has a certain error; the correction curve method of the steam turbine plant is determined according to the back pressure-power correction curve provided by the steam turbine plant, but the curve is usually given only a design load working condition, and the correction error is larger for a partial load working condition. When the variable working condition of the condenser is calculated, the overall heat transfer coefficient is not corrected by considering the steam load in unit area, and after the deep peak shaving and heat supply transformation of the unit are not considered in the cold end system optimization of the conventional wet cooling unit, the influence of the heat load change of the condenser on the optimal vacuum of the unit is larger, and the economic performance of the unit is reduced due to larger errors in the heat supply of the unit.
Therefore, we propose a cold end optimization method under all working conditions of a wet-cold thermal power unit.
Disclosure of Invention
The invention aims to overcome the problems in the prior art and provide the cold end optimization method for the all-condition of the wet-cold thermal power unit, and simultaneously, the pure condensation condition and the heat supply condition of the unit are considered, so that errors are reduced, and the condition of reduced economy of the unit is reduced.
In order to achieve the technical purpose and the technical effect, the invention is realized by the following technical scheme:
a method for optimizing a cold end of a wet cooling thermal power unit under all working conditions comprises the following steps:
(1) Influence of heat supply and steam extraction on heat load of condenser
Variable working condition calculation basis Friedel formula of steam turbine
The heat supply and steam extraction of the steam turbine can be generally extracted from a reheating cold section pipeline, a reheating hot section pipeline and a medium-low pressure communicating pipe of the steam turbine, the unit heat supply and steam extraction quantity under different loads at different positions has different influences on the generating power of the unit, and the power grid dispatching is kept unchanged for ensuring the electric power of the steam inlet unit, so that the main steam flow of the steam turbine is different, and the heat load of a condenser is different;
finally, obtaining the relation Q=f (x) of the change of the condenser heat load along with the extraction steam quantity 1 ,x 2 ,...,x n )；
(2) Circulating water flow and power relationship
Under different running modes of the circulating water pump, the relation between the consumption power increment of the circulating water pump and the circulating water flow is expressed as delta P p ＝f(D w )；
(3) Condenser variable working condition calculation
According to Q in (1) and D in (2) w Calculating the temperature rise of circulating water
Calculating the overall heat transfer coefficient K=K of the condenser 0 β c β t β m β Q ；
End difference of condenser
The condensing temperature of steam in the condenser is t s ＝t w1 +Δt+δ t ；
Checking the water vapor property table, t in the prior art s Corresponding to saturation pressure P s ，P s The pressure of the condenser is obtained;
(4) Micro-increment force calculation
The optimal vacuum value of the turbine condenser is larger than the limit vacuum p 2c The pressure of the condenser changes from p 2 Expansion to p 2c Calculating the micro-increment force delta P of the steam turbine e ，
w 2c 、χ、x m Usually less variation, gives
The pressure change curve of the condenser is designed according to the pressure change curve of the condenser, so that the micro-increment force change of the steam turbine can be obtained when the pressure of the condenser is changed under different electric loads of the unit;
based on the turbine power P, the condenser pressure P calculated in (3) s To obtain delta P e ＝f(p s ,P)；
(5) Optimal vacuum of condenser
With the electric load P and the heat supply x of the unit 1 ,x 2 ,...,x n Circulating water flow D w And the inlet temperature t of circulating cooling water w1 As an argument, an objective function F (P, x 1 ,x 2 ,...,x n ,D w ,t w1 )＝ΔP e -ΔP p ；
At the unit electric load P and the heat supply x 1 ,x 2 ,...,x n Inlet temperature t of circulating cooling water w1 Under certain conditions, the circulating water flow D is changed through the running mode of the circulating water pump w The maximum value F (P, x) 1 ,x 2 ,...,x n ,D w ,t w1 ) max At this time, the pressure P corresponds to the condenser pressure s The condenser is the optimal vacuum, and the corresponding operation mode of the circulating water pump is the optimal operation mode of the circulating water pump.
Preferably, under the variable working condition of the steam turbine, the relation between the pressure and the flow before the cascade stage can be obtained according to the Friedel formula; the efficiency of each stage group of the steam turbine is obtained by calculating the efficiency of the corresponding stage group according to the heat balance map data provided by the steam turbine plant and fitting a curve; when calculating parameters of each point of the heat recovery system, keeping the end difference of the heater unchanged; according to the definition of the difference between the upper end and the lower end and the parameters of the water feeding pump, the water temperature and the water enthalpy of the outlet of each heater and the hydrophobic temperature and enthalpy value of the outlet of each heater are obtained; for the auxiliary steam-water component, parameters of the auxiliary steam-water component in calculation change along with the source, and the auxiliary steam share is regarded as unchanged; the change of the extraction pressure of each section will cause the change of the extraction specific enthalpy and the water supply temperature of the outlet and inlet of each heater, which will generate new extraction flow; therefore, iterative calculation is needed to be carried out again according to the new extraction pressure until the deviation of the extraction pressure obtained by two adjacent iterations is less than 0.01%;
according to the method, parameters of each stage group and heater under the variable working condition of the steam turbine and the power generated by the steam turbine are obtained.
Preferably, a field test method is adopted for determining the circulating water flow and the power, and the consumed electric power and the circulating water flow of the circulating water pump are tested under different numbers and different rotating speeds; the influence of the consumed electric power of the circulating water pump and the circulating water flow on the change of the heat load of the steam turbine and the temperature of the circulating water is small, and the circulating water pump can be processed as a fixed value under different working conditions.
Preferably, the objective function represents the difference between the unit micropower and the power consumption increased by the circulating water pump.
Compared with the prior art, the invention has the following beneficial effects:
the invention provides a cold end optimization method under all working conditions of a wet-cooling thermal power unit, which comprises the following three steps:
1. the influence of heat supply steam extraction on the heat load of the condenser is calculated;
2. a micro-increment force calculation method;
3. considering the influence of the steam load in unit area on the heat transfer coefficient, calculating the overall heat transfer coefficient of the condenser; meanwhile, the pure condensation working condition and the heat supply working condition of the unit are considered, the optimal operation of the cold end equipment under the full working condition of the wet cooling unit is realized, the error is reduced, the condition that the economy of the unit is reduced, and the energy-saving effect is remarkable.
Of course, it is not necessary for any one product to practice the invention to achieve all of the advantages set forth above at the same time.
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In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed for the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a schematic diagram of a prior art structure;
FIG. 2 is a schematic diagram of the structure of the present invention;
FIG. 3 is a graph of the micro-augmentation force of the steam turbine of the present invention.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Example 1
The invention provides a technical scheme that: a method for optimizing a cold end of a wet cooling thermal power unit under all working conditions comprises the following steps:
(1) Influence of heat supply and steam extraction on heat load of condenser
Variable working condition calculation basis Friedel formula of steam turbine
Wherein G is 0 Represent class group flow, p 0 、p g Respectively represent the initial pressure and the back pressure of the level group, T 0 Indicating the initial temperature of the stage group, and subscript 1 indicates the variable condition parameter.
Under the variable working condition of the steam turbine, the relation between the pressure and the flow before the cascade stage can be obtained according to the Friedel formula. And calculating the efficiency of the corresponding stage group according to the heat balance map data provided by the turbine plant and fitting a curve to obtain the efficiency of each stage group of the turbine. And when the parameters of each point of the heat recovery system are calculated, the end difference of the heater is kept unchanged. And (5) according to the definition of the difference between the upper end and the lower end and the parameters of the water feeding pump, obtaining the water temperature and the enthalpy of the outlet of each heater and the temperature and the enthalpy value of the drain water of the outlet of each heater. For the auxiliary steam-water component, the parameters of the auxiliary steam-water component in the calculation are changed according to the source, and the auxiliary steam share is regarded as unchanged. The change of the extraction pressure of each section will cause the change of the extraction specific enthalpy and the water supply temperature of the outlet and inlet of each heater, which will generate new extraction flow. Therefore, iterative calculation is needed to be carried out again according to the new extraction pressure until the deviation of the extraction pressure obtained by two adjacent iterations is less than 0.01%.
According to the method, parameters (pressure, temperature, enthalpy and the like) of each stage group and the heater under the variable working condition of the steam turbine can be obtained, and the power generated by the steam turbine.
The heat supply and steam extraction of the steam turbine can be generally extracted from a reheating cold section pipeline, a reheating hot section pipeline and a medium-low pressure communicating pipe of the steam turbine, the unit heat supply and steam extraction quantity under different loads at different positions has different influences on the generating power of the unit, and the power grid dispatching is kept unchanged for ensuring the electric power of the steam inlet unit, so that the main steam flow of the steam turbine is different, and the heat load of a condenser is further different. Finally, the heat of the condenser can be obtainedLoad-to-extraction variation relationship q=f (x 1 ,x 2 ,...,x n ) Q represents the heat load of the condenser, x 1 ,x 2 ,...,x n The steam extraction quantity of different heat supply steam extraction positions under a certain load of the unit is represented.
(2) Circulating water flow and power relationship
At present, a single unit of a wet cooling thermal power unit is generally provided with 2-3 circulating water pumps, and the circulating water pumps can be divided into constant-speed pumps or double-speed pumps according to actual needs. And the circulating water flow and the power are determined by adopting a field test method, and the consumed electric power and the circulating water flow of the circulating water pump are tested under different numbers and different rotating speeds. The influence of the consumed electric power of the circulating water pump and the circulating water flow on the change of the heat load of the steam turbine and the temperature of the circulating water is small, and the circulating water pump can be processed as a fixed value under different working conditions.
Under different running modes of the circulating water pump, the relation between the consumption power increment of the circulating water pump and the circulating water flow is expressed as delta P p ＝f(D w )，D w Representing the flow of circulating water.
(3) Condenser variable working condition calculation
According to (1) condenser heat load Q and (2) circulating water flow D w Calculating the temperature rise of circulating water
Wherein C is p Represents the specific heat capacity of the circulating water;
calculating the overall heat transfer coefficient of the condenser according to a calculation formula recommended by the American heat transfer institute HEI and considering the influence of the steam load in unit area on the heat transfer coefficient, wherein the overall heat transfer coefficient of the condenser is as follows
K＝K 0 β c β t β m β Q ；
K 0 Representing the basic heat transfer coefficient;
β c representing the condenser tube cleaning coefficient;
β t representing the cooling water inlet temperature correction coefficient;
β m representing the pipe and the wall thickness correction coefficient;
β Q representing the steam load correction coefficient of the condenser in unit area, adopting a Bie Erman formula to calculate the steam load change correction method, and beta in a certain heat load range Q The value is 1; further reduction of thermal load, beta Q The value is less than 1.
End difference of condenser
Wherein A represents the design heat exchange area of the condenser;
the condensing temperature of steam in the condenser is t s ＝t w1 +Δt+δ t ，t w1 The inlet temperature of the circulating cooling water is;
checking the water vapor property table, t in the prior art s Corresponding to saturation pressure P s ，P s The condenser pressure is obtained.
(4) Micro-increment force calculation
The optimal vacuum value of the turbine condenser is larger than the limit vacuum p 2c The pressure of the condenser changes from p 2 Expansion to p 2c Calculating the micro-increment force delta P of the steam turbine e ，
G represents the steam inlet flow of the low-pressure cylinder;
x m indicating back pressure from p 2 Expansion to p 2c Average dryness of steam of the process;
χ represents the coefficient of the lowest level of backheating steam extraction quantity reduction and power increase caused by the rising of back pressure and the rising of condensation water temperature;
η' denotes the back pressure from p 2 Expansion to p 2c The relative internal efficiency of the process, but without deduction of moisture loss and residual rate loss;
kappa represents an isentropic index;
n represents a polytropic exponent;
u represents a circumferential velocity;
w 2c representing the critical relative speed of the outlet of the movable blade;
β 2 the included angle between the relative speed of the movable vane and the rotation plane of the impeller is shown.
A b Represents the throat cross-sectional area of the bucket;
w 2c 、χ、x m usually less variation, gives
Through the back pressure versus power change curve of the condenser under the design working condition, the micro-increment force change of the steam turbine can be obtained when the pressure of the condenser is changed under different electric loads of the unit.
The condenser pressure P calculated in (3) according to the turbine power P (usually specified by grid schedule) s To obtain delta P e ＝f(p s ,P)。
(5) Optimal vacuum of condenser
With the electric load P and the heat supply x of the unit 1 ,x 2 ,...,x n Circulating water flow D w And the inlet temperature t of circulating cooling water w1 As an argument, an objective function F (P, x 1 ,x 2 ,...,x n ,D w ,t w1 )＝ΔP e -ΔP p The function represents the difference between the micro-increment power of the unit and the increment power of the circulating water pump;
at the unit electric load P and the heat supply x 1 ,x 2 ,...,x n Inlet temperature t of circulating cooling water w1 Under certain conditions, the circulating water flow D is changed through the running mode of the circulating water pump w The maximum value F (P, x) 1 ,x 2 ,...,x n ,D w ,t w1 ) max At this time, the pressure P corresponds to the condenser pressure s The condenser is the optimal vacuum, and the corresponding operation mode of the circulating water pump is the optimal operation mode of the circulating water pump.
The method is only suitable for the pure condensation working condition of the wet-cold thermal power unit according to the traditional cold end optimization mode, and the pure condensation working condition and the heat supply working condition of the unit are considered simultaneously, so that the optimal operation of the cold end equipment of the wet-cold unit under the full working condition is realized, errors are reduced, the condition of causing the economic decline of the unit is reduced, and the energy-saving effect is remarkable.
Example 2
Some 600MW subcritical wet cooling unit, condenser configuration model is N34000-1, cooling area 34000m3, design backpressure 4.9kPa, circulating water flow 72000t/h, circulating water inlet water temperature 20 ℃, circulating water temperature 8.9 ℃, end difference 3.61 ℃, condenser cooling pipe specification phi 25 x 0.7mm, material is TP304, design flow rate 2.24m/s in the pipe diameter cooling pipe, cleaning coefficient 0.9. Two double-speed pumps with the same model are designed for the circulating water pump, and four running modes of single pump low speed, single pump high speed, one high and one low, and two high speeds can be realized.
Taking the electric load of the unit of 450MW and the heat supply of the reheating heat section of 100t/h and the heat supply of the medium-pressure heat supply of 200t/h as an example, calculating the optimal vacuum of the condenser at the moment.
(1) Influence of heat supply and steam extraction on heat load
The power generated by the steam turbine is 450MW, and the heat load Q= 418398kW of the condenser is calculated according to the heat supply amount. (condenser heat load under pure condensing condition is Q= 555869 kW)
(2) Circulating water flow and power relationship
Obtained by field test data
| Circulating water flow t/h | Total power consumption kW | |
| Single low speed | 36300 | 2010 |
| Single high speed | 43800 | 2830 |
| One high and one low | 64500 | 4840 |
| Double high speed | 71000 | 5580 |
(3) Condenser pressure calculation
Assuming different circulating cooling water inlet temperatures t w1 Calculating the pressure p of the corresponding condenser according to the circulating water flow rate of the circulating water pump in the step (2) under different four different running modes s 。
(4) Turbine micro-increment force calculation
And obtaining a micro-increment force curve of the steam turbine when the pressure of the condenser of the unit changes under the power generation of 450MW according to a curve of back pressure of the condenser versus power under the design working condition, wherein the curve is shown in figure 3.
(5) Optimal vacuum determination for condenser
The flow D is generated by the heat load Q of the condenser in (1) and the flow D of four different circulating water pumps in (2) in the operation mode w Assume different circulating cooling water inlet temperatures t w1 Calculating ΔP from (2) and (4) p 、ΔP e Calculating the maximum value F (P, x) 1 ,x 2 ,...,x n ,D w ,t w1 ) max At this time, the pressure p corresponds to the condenser pressure s The condenser is the optimal vacuum, and the corresponding operation mode of the circulating water pump is the optimal operation mode of the circulating water pump;
the calculation results are shown in the following table;
as can be seen from the data in the table, when the inlet temperature of the circulating water is 10 ℃, 15 ℃ and 20 ℃, if the heat supply unit is compared with the conventional method according to the method, the energy saving amounts are 402kW, 629kW and 251kW respectively, and the energy saving effect is remarkable.
In the description of the present specification, the descriptions of the terms "one embodiment," "example," "specific example," and the like, mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The preferred embodiments of the invention disclosed above are intended only to assist in the explanation of the invention. The preferred embodiments are not exhaustive or to limit the invention to the precise form disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best understand and utilize the invention. The invention is limited only by the claims and the full scope and equivalents thereof.
Claims (3)
1. A cold end optimization method for all-condition of a wet-cooling thermal power unit is characterized by comprising the following steps of: the method comprises the following steps:
(1) Influence of heat supply and steam extraction on heat load of condenser
Variable working condition calculation basis Friedel formula of steam turbine
The heat supply and extraction of the steam turbine are extracted from a reheating cold section pipeline, a reheating hot section pipeline and a medium-low pressure communicating pipe of the steam turbine, the unit heat supply and extraction quantity under different loads at different positions has different influences on the generating power of the unit, and the power grid dispatching is kept unchanged for ensuring the electric power of the steam inlet unit, so that the main steam flow of the steam turbine is different to further cause the heat load of a condenser to be different;
finally, obtaining the relation Q=f (x) of the change of the condenser heat load along with the extraction steam quantity 1 ,x 2 ,...,x n )；
(2) Circulating water flow and power relationship
The method comprises the steps of determining circulating water flow and power by adopting a field test method, and testing the consumed electric power and circulating water flow of a circulating water pump under different numbers and different rotating speeds; the influence of the consumed electric power of the circulating water pump and the circulating water flow on the change of the heat load and the circulating water temperature of the steam turbine is small, and the consumed electric power and the circulating water flow are treated as values under different working conditions;
under different running modes of the circulating water pump, the relation between the consumption power increment of the circulating water pump and the circulating water flow is expressed as delta P p ＝f(D w )，D w Representing the flow of circulating water;
(3) Condenser variable working condition calculation
According to Q in (1) and D in (2) w Calculating the temperature rise of circulating water
Calculating the overall heat transfer coefficient K=K of the condenser 0 β c β t β m β Q ；
End difference of condenser
The condensing temperature of steam in the condenser is t s ＝t w1 +△t+δ t ；
Checking the steam property table, t s Corresponding to saturation pressure P s ，P s The pressure of the condenser is obtained;
(4) Micro-increment force calculation
The optimal vacuum value of the turbine condenser is larger than the limitVacuum p 2c The pressure of the condenser changes from p 2 Expansion to p 2c Calculating the micro-increment force delta P of the steam turbine e ，
w 2c 、χ、x m Usually less variation, gives
The pressure change curve of the condenser is designed according to the back pressure to power change curve of the condenser under the working condition, so that the micro-increment force change of the steam turbine is obtained when the pressure of the condenser is changed under different electric loads of the unit;
based on the turbine power P, the condenser pressure P calculated in (3) s To obtain DeltaP e ＝f(p s ,P)；
(5) Optimal vacuum of condenser
With the electric load P and the heat supply x of the unit 1 ,x 2 ,...,x n Circulating water flow D w And the inlet temperature t of circulating cooling water w1 As an argument, an objective function F (P, x 1 ,x 2 ,...,x n ,D w ,t w1 )＝△P e -△P p ；
At the unit electric load P and the heat supply x 1 ,x 2 ,...,x n Inlet temperature t of circulating cooling water w1 Under certain conditions, the circulating water flow D is changed through the running mode of the circulating water pump w Obtaining the maximum value F (P, x) 1 ,x 2 ,...,x n ,D w ,t w1 ) max At this time, the pressure P corresponds to the condenser pressure s The condenser is the optimal vacuum, and the corresponding operation mode of the circulating water pump is the optimal operation mode of the circulating water pump.
2. The method for optimizing the cold end of the wet cooling thermal power unit under all working conditions according to claim 1 is characterized by comprising the following steps: (1) Under the variable working condition of the steam turbine, obtaining the relation between the pressure and the flow before the cascade according to the Friedel formula; the efficiency of each stage group of the steam turbine is obtained by calculating the efficiency of the corresponding stage group according to the heat balance map data provided by the steam turbine plant and fitting a curve; when calculating parameters of each point of the heat recovery system, keeping the end difference of the heater unchanged; according to the definition of the difference between the upper end and the lower end and the parameters of the water feeding pump, the water temperature and the water enthalpy of the outlet of each heater and the hydrophobic temperature and enthalpy value of the outlet of each heater are obtained; for the auxiliary steam-water component, parameters of the auxiliary steam-water component in calculation change along with the source, and the auxiliary steam share is regarded as unchanged; the change of the extraction pressure of each section will cause the change of the extraction specific enthalpy and the water supply temperature of the outlet and inlet of each heater, which will generate new extraction flow; therefore, iterative calculation is needed to be carried out again according to the new extraction pressure until the deviation of the extraction pressure obtained by two adjacent iterations is less than 0.01%;
according to the method, parameters of each stage group and heater under the variable working condition of the steam turbine and the power generated by the steam turbine are obtained.
3. The method for optimizing the cold end of the wet cooling thermal power unit under all working conditions according to claim 1 is characterized by comprising the following steps: (5) The objective function represents the difference between the micro-increment power of the unit and the increment power of the circulating water pump.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN202111176345.9A CN113864013B (en) | 2021-10-09 | 2021-10-09 | Cold end optimization method for all-condition of wet-cooling thermal power unit |
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