Summary of the invention
At the problems referred to above, the purpose of this invention is to provide a kind of emulation simulator at supercritical DC furnace, this emulation simulator can be good at simulating the main operational factor of supercritical DC furnace.
For achieving the above object, the present invention takes following technical scheme: a kind of emulation simulator of supercritical DC furnace is characterized in that: it comprises the emulation of separator outlet pressure, the preceding pressure emulation of machine, first class pressure and unit load emulation and four parts of separator outlet enthalpy emulation; The emulation of described separator outlet pressure partly comprises one group of function generator (1~4), and the input end of function generator (1) is the coal amount, and its output terminal connects the dividend input end of a divider (a) behind three rank inertial elements; The divisor input end of described divider (a) is main feedwater flow, the input end of its output terminal contiguous function generator 2; The output terminal of described function generator (2) connects an input end of a multiplier (a); Another input end of described multiplier (a) is main feedwater flow, the input end of its output terminal contiguous function generator (3); The output terminal of described function generator (3) connects a subtracter (a)+input end after through the quadravalence inertial element; Described subtracter (a)-output terminal of input end contiguous function generator (4), its output terminal connects the input end of an integrator (a); The output terminal of described integrator (a) connects a subtracter (b)+input end; Described subtracter (b)-input end connects the output terminal of an integrator (b), and its output terminal connects the input end of described function generator (4); Pressure emulation partly comprises a function generator (5) before the described machine, and the input end of described function generator (5) is a main steam temperature, and its output terminal connects an input end of a multiplier (b); Another input end of described multiplier (b) connects the output terminal of a totalizer (a), its output terminal connect a subtracter (c)+input end; Described subtracter (c)-input end connects the output terminal of a multiplier (c), and its output terminal connects the input end of described integrator (b); An input end of described totalizer (a) is the desuperheating water flow, and its another input end connects the output terminal of described function generator (4); Described first class pressure and unit load emulation partly comprise one group of function generator (6~9), and the input end of function generator (6) connects the output terminal of described integrator (b); The output terminal of described function generator (6) connects an input end of described multiplier (c); The input end of function generator (7) is a steam turbine pitch aperture, and its output terminal connects another input end of described multiplier (c); The input end of the output terminal contiguous function generator (8) of described multiplier (c); The output terminal of described function generator (8) is contiguous function generator (9) behind first order inertial loop, and the output terminal of described function generator (9) connects first order inertial loop; The emulation of described separator outlet enthalpy partly comprises one group of function generator (11~12), and the input end of function generator (11) is the coal amount, and its output terminal connects the dividend input end of a divider (b) behind three rank inertial elements; Main feedwater flow connects the divisor input end of described divider (b) behind first order inertial loop, the output terminal of described divider (b) connects an input end of a totalizer (c); The input end of function generator (12) is a separator outlet pressure, and its output terminal connects another input end of described totalizer (c), and the output terminal of described totalizer (c) is the separator outlet enthalpy.
Described first class pressure and unit load emulation partly comprise one group of function generator (6~10), and the input end of function generator (6), (7), (10) all connects the output terminal of described integrator (b); The output terminal of described function generator (6) connects the input end of a totalizer (b); The output terminal of function generator (7) connects an input end of described multiplier (c); Another input end of described multiplier (c) is a steam turbine pitch aperture, and its output terminal connects the input end of described totalizer (b); The output terminal of described function generator (10) connects an input end of a multiplier (d); Another input end of described multiplier (d) connects the output terminal of a multiplier (e), and its output terminal connects the input end of described totalizer (b); The input end of described multiplier (e) is a steam turbine pitch aperture; The input end of the output terminal contiguous function generator (8) of described totalizer (b); The output terminal of described function generator (8) is contiguous function generator (9) behind first order inertial loop, and the output terminal of described function generator (9) connects first order inertial loop; Subtracter (c) before the described machine in the pressure emulation part-input end connects the output terminal of described totalizer (b).
The present invention is owing to take above technical scheme, it has the following advantages: 1, the present invention is the mechanism based on monoblock, and the mathematical model of the fuel-burning power plant monoblock direct current stove of setting up in conjunction with the method for experience modeling, therefore guaranteeing the rational while, also can be good in actual applications realizing.2, the setting of each parameter is relatively independent in the present invention, therefore has very flexible processing mode in the configuration of parameter.3, because the present invention is the specific implementation in power plant's Distributed Control System (DCS), therefore can well in power plant, be verified and use.The present invention uses proof to can be good at the actual operation parameters of on-line tracing unit through the scene, therefore can help to analyze the control characteristic of supercritical DC furnace, thereby propose more rational controlling schemes.
Embodiment
Below in conjunction with drawings and Examples the present invention is described in detail.
As shown in Figure 1, the present invention is the mechanism based on the fuel-burning power plant monoblock, and the mathematical model of the fuel-burning power plant monoblock supercritical DC furnace of setting up in conjunction with the method for experience modeling, this mathematical model comprises pressure emulation part B before separator outlet pressure emulation part A, the machine, first class pressure and unit load emulation portion C and separator outlet enthalpy emulation part D.
Separator outlet pressure emulation part A comprises one group of function generator 1~4, and the input end of function generator 1 is coal amount W, and its output terminal connects the dividend input end of a divider a behind three rank inertial elements.The divisor input end of divider a is main feedwater flow Q, the input end of its output terminal contiguous function generator 2.The output terminal of function generator 2 connects the input end of a multiplier a.Another input end of multiplier a is main feedwater flow Q, the input end of its output terminal contiguous function generator 3.The output terminal of function generator 3 connects a subtracter a's after through the quadravalence inertial element+input end.Subtracter a-output terminal of input end contiguous function generator 4, its output terminal connects the input end of an integrator a.The output terminal of integrator a connects a subtracter b's+input end.Subtracter b-input end connects the output terminal of an integrator b, the input end of its output terminal contiguous function generator 4.The output terminal of function generator 4 connects a totalizer a.
The input variable of function generator 1 is coal amount W, and it is output as the feedwater flow Q of coal amount W correspondence
1, the output of function generator 1 behind three rank inertial elements divided by main feedwater flow Q.The effect of function generator 1 is as feedwater flow Q
1When not matching with main feedwater flow Q, coal amount W is to the correction that influences of main feedwater flow Q.Function generator 2 effect is that coal amount W does not revise main feedwater flow Q when the matching degree of coal amount W that enters boiler and main feedwater flow Q within the specific limits the time, and when exceeding certain scope, coal amount W ability is revised main feedwater flow Q.
The input variable of function generator 3 is the process function generator 1 revised main feedwater flow Q that enters economizer, reference variable-main steam flow V in the middle of it is output as.The function of function generator 3 is exactly that the main feedwater flow Q and the coal amount W that enter boiler are converted to the corresponding main steam flow V that enters boiler, enter boiler combustion with following quadravalence inertial element analog fuel again, and to the main feedwater flow Q pressurization back combustion characteristics to this section of separator inlet boiler of boiler of heating.
The input variable of function generator 4 is the separator outlet pressure P
bWith pressure P before the machine
tDifference, this difference is by the separator outlet pressure P
bWith pressure P before the machine
tInput subtracter b calculates, and it is output as the corresponding main steam flow V of this difference pressure drop
1The function of function generator 4 is these interval pressure-flow characteristics of superheater bringing-up section of boiler between simulation enters the mouth from the separator outlet to the steam turbine, by the separator outlet pressure P
bWith pressure P before the machine
tDifference calculate from the separator outlet to the steam turbine main steam flow V in the superheater bringing-up section of boiler between the inlet
1, main steam flow V
1Calculate the separator outlet pressure P with the difference of the main steam flow V that enters boiler separator through integrator a
b
Pressure emulation part B comprises a function generator 5 before the machine, and the input end of function generator 5 is main steam temperature T, and its output terminal connects the input end of a multiplier b.Another input end of multiplier b connects the output terminal of a totalizer a, its output terminal connect a subtracter c+input end.Subtracter c-input end connects the output terminal of a multiplier c, and its output terminal connects the input end of an integrator b.The output terminal of integrator b connects subtracter b's-input end.The input end of totalizer a is desuperheating water flow L, the output terminal of its another input end contiguous function generator 4.When the energy that the effect of function generator 5 is contained when the high steam of temperature was big, the output of function generator 5 was greater than 1, otherwise then less than 1, it has embodied the influence of main steam temperature T to steam quality.
First class pressure and unit load emulation portion C comprise one group of function generator 6~10, and the input end of function generator 6,7,10 all connects the output terminal of integrator b.The output terminal of function generator 6 connects the input end of a totalizer b, and the output terminal of function generator 7 connects the input end of a multiplier c.Another input end of multiplier c is steam turbine pitch aperture K, and its output terminal connects the input end of totalizer b.The output terminal of function generator 10 connects the input end of a multiplier d.Another input end of multiplier d connects the output terminal of a multiplier e, and its output terminal connects the input end of totalizer b.The input end of multiplier e is steam turbine pitch aperture K, the output terminal of totalizer b connect subtracter c-input end of input end and function generator 8.The output terminal of function generator 8 is contiguous function generator 9 behind first order inertial loop, and the output terminal of function generator 9 connects first order inertial loop.
The input variable of function generator 6,7,10 is a pressure P before the machine
t, their output and steam turbine pitch aperture K calculate the main steam flow V after steam does work by the bilinearity fitting method
2
The input variable of function generator 8 is the main steam flow V through steam acting behind the steam turbine pitch
2, its output is first class pressure P behind first order inertial loop
1The entry variable of function generator 9 is first class pressure P
1, its output is unit load NE behind first order inertial loop.
Separator outlet enthalpy emulation part D comprises one group of function generator 11~12, and the input end of function generator 11 is coal amount W, and its output terminal connects the dividend input end of a divider b behind three rank inertial elements.Main feedwater flow Q connects the divisor input end of divider b behind first order inertial loop, the output terminal of divider b connects the input end of a totalizer c.The input end of function generator 12 is the separator outlet pressure P
b, its output terminal connects another input end of totalizer c, and the output terminal of totalizer c is separator outlet enthalpy H.
In the foregoing description, the input variable of the function generator 6,7,10 in first class pressure and the unit load emulation portion C is a pressure P before the machine
t, their output and steam turbine pitch aperture K calculate the main steam flow V after steam does work by the bilinearity fitting method
2But when supercritical DC furnace moves, generally carry out lifting load under normal occlusion science and engineering condition, can meet the needs of production, therefore can adopt the main steam flow V after simpler method is done work to steam here according to certain sliding pressure curve
2Calculate, promptly can simplify processing first class pressure and unit load emulation portion C.
As shown in Figure 2, when adopting the mathematical model of simplifying, the input end of function generator 6 connects the output terminal of integrator b, and its output terminal connects the input end of multiplier c.The input end of function generator 7 is steam turbine pitch aperture K, and its output terminal connects another input end of multiplier c.The input end of the direct contiguous function generator 8 of the output terminal of multiplier c, and before the unit machine among the pressure emulation part B subtracter c-input end connects the output terminal of multiplier c.This moment, the input variable of function generator 6 was a pressure P before the machine
t, it is output as the preceding pressure P of this machine
tFollowing corresponding main steam flow.The function of function generator 6 is that the simulation main steam enters the variation characteristic of steam turbine to this section of steam turbine speed control porthole steam turbine acting main steam flow.The entry variable of function generator 7 is steam turbine pitch aperture K, and it is output as effective steam turbine pitch aperture.The function of function generator 7 is simulation steam turbine pitch aperture K influences to main steam flow, the main steam flow of the output of its output and function generator 6 after multiplier c product obtains the steam acting.The output of function generator 4 and desuperheating water flow L sum are the steam flow that enters superheater, and this steam flow is revised difference pressure P before integrator b calculates the machine of steam turbine of back and main steam flow through function generator 5
t
As shown in Figure 1 and Figure 2, in DCS (scattered control system), above-mentioned mathematical model is carried out Logical Configuration, as follows each operational factor in the above-mentioned mathematical model (mainly being function generator 1~12) is configured then:
When 1) in DCS, searching the operation of actual motion set steady, corresponding relation under the different load between each operational factor, operational factor comprise main feedwater flow Q, desuperheating water flow L, main steam temperature T, coal amount W, steam turbine pitch aperture K, separator outlet pressure P
b, pressure P before the machine
t, first class pressure P
1, unit load NE and main steam flow.
2) by the probability statistics of the operational factor of actual motion unit in the step 1) each parameter in the above-mentioned mathematical model is carried out static configuration, make the static output parameter of above-mentioned mathematical model under each load section can be good at embodying the characteristic of actual motion unit operation parameter.
3) rule of thumb value provides between the inertial time of inertial element in the above-mentioned mathematical model and the integral time of integrator.
4) parameter of in unit operation above-mentioned calculated with mathematical model being come out (comprises the separator outlet pressure P
b, pressure P before the machine
t, first class pressure P
1, unit load NE and separator outlet enthalpy H) compare analysis with the parameter of actual motion unit: if the final numerical value of each parameter of above-mentioned mathematical model and the operational factor of actual motion unit are the same, just and the operational factor of actual motion unit the individual mistiming is arranged, then change between the inertial time of corresponding inertial element integral time with integrator; If the operational factor of numerical value that each parameter of above-mentioned mathematical model is final and actual motion unit is different, then need to revise corresponding function generator, can be good at being complementary up to above-mentioned mathematical model with the actual motion unit.
As shown in Figure 3, be the load change curve map that adopts the present invention in the power station commissioning process, to obtain.Through field adjustable, a supercritical DC furnace load is raised to 500MW from 425MW, pressure P before separator outlet enthalpy H, the machine from figure
t, the separator outlet pressure P
bWith first class pressure P
1Curve as can be seen, the present invention can both well follow the tracks of the actual parameter of boiler in this course, has well finished the task of numerical simulation.
Although disclose preferred embodiment of the present invention and accompanying drawing for the purpose of illustration, its purpose is to help to understand content of the present invention and implement according to this, but person skilled in the art, without departing from the spirit and scope of the invention and the appended claims, can do various replacements, variation and retouching.Therefore, the present invention should not be limited to most preferred embodiment and the disclosed content of accompanying drawing, and protection scope of the present invention is as the criterion with the scope that appending claims was defined.