CN1528917A - Automatic control method of blast-furnace top pressure stability for blast-furnace gas top pressure power generation apparatus - Google Patents

Abstract

The invention discloses an automatic control method for blast furnace top pressure in blast furnace coal gas residue pressure electricity generator, it uses automatic control software to realized the fluctuating real-time automatic control of pressure, thus ensures the TRT appliance can meet the demands of blast furnace refining process extremely. The method includes: (1) establishes mathematics and physics equation; (2) Xi parameter calculating and switching algorithm; (3) establishes automatic control system; (4) works out control software according to mathematics and physics equation and specialist algorithm. The invention can enhance the scientific content of TRT appliance product, enhances the competitive power of it. It solves difficulty in variable flow calculation and control technology, changes the analog control into digital control, and realizes the on-line supervising of pressure in TRT appliance.

Description

The blast furnace roof pressure stability autocontrol method of blast furnace gas excess pressure power generating device

Technical field

The invention belongs to the energy and field of dynamic engineering, relate to the blast furnace roof pressure stability autocontrol method of blast furnace gas excess pressure power generating device (BlastFurnace Top Gas Recovery Turbine Unit) (hereinafter to be referred as TRT).

Background technology

TRT device blast furnace roof pressure stability is meant the characteristic by the fluctuation variation tendency of the fluctuation time of recovery of the fluctuation range of blast furnace ironmaking process furnace top pressure, roof pressure power and roof pressure power.The blast furnace roof pressure Calculation on stability machine control of so-called TRT device is meant by using auto-control software and realizes the real-time control automatically of the fluctuation of blast furnace ironmaking process furnace top pressure.

Term

TRT: blast furnace gas excess pressure power generating device (The blast furnace top pressure powerrecovery turbine unit)

Stator blade: in working order down, can be with respect to stator immobilized such as TRT casings around the part with good aerodynamic characteristic of blade axle center rotation.

Stator blade is adjustable: adopt drive technology, stator blade can be rotated around the blade axle center, by changing the TRT operating mode, satisfy the arts demand of blast furnace system.

Roof pressure: the blast furnace ironmaking process furnace top pressure is one of blast furnace ironmaking process leading indicator.

Roof pressure stability: the fluctuation time of recovery of the fluctuation range of blast furnace ironmaking process furnace top pressure, roof pressure power and the fluctuation variation tendency of roof pressure power have reflected roof pressure stability.

Automatically control: without manpower with the direct control that installs such as mechanical, electric.

STPC software: TRT roof pressure control special software.

Since 1979, China began to develop the TRT device, had manufactured and designed more than 30 cover TRT device when approving and initiate a project to this.Utilize the TRT device to generate electricity, the user often worries that the TRT device can reduce the stability of blast furnace roof pressure, thereby influences the main flow technological process.

The contriver retrieves following document:

Leaf is green for a long time, the development and the innovation of the saturating bottle of blast-furnace top gas recovery (TRT), " energy-conservation ", 2000 the 8th phases.

Wu Yaping, Wuhan Iron and Steel Plant No. 3 blast furnace TRT As-Is analysis and potentiality are inquired into, " Wuhan Iron and Steel Plant technology ", 1993 the 3rd phases.

Sun Yuansheng does wet dedusting---top gas pressure control system, " Taiyuan Iron and Steel Co. science and technology ", 1991 1 phases;

Zhang Hongqing, Liu discriminates, etc., Wuhan Iron and Steel Plant 2# blast furnace TRT controls automatically, " metallurgical automation ", 2001 the 4th phases;

Huang Jinghua, TRT influence the solution of blast furnace roof pressure problem, " metallurgical power ", 2000 the 4th phases;

Peter Kreuzhuber, Slovakia's Kosice metallurgical works utilizes top gas turbo-expander recovered energy, " metallurgical equipment and technology ", 1997,2.

Cause that the unsettled reason of blast furnace roof pressure is many-sided, principal element has: inhomogeneous (varying duty) in the blast-furnace smelting raw material interpolation process; High temperature, multiphase flow, physics and the chemical transformation of multiple medium in the blast furnace; The pressure of the gas blower of blast furnace air inlet and fluctuations in discharge; Other factors such as fly-ash separator laying dust, pipeline leakage etc. cause some random factors that the damping of flowing changes.Because above-mentioned factor has uncertainty mostly, and the influence that furnace top pressure is changed has non-linear characteristics.Therefore when promoting the TRT technology, should emphasize the advantage of this technical energy saving environmental protection, also will carry out systematic Study, satisfy the requirement of blast-furnace smelting main flow technology to greatest extent the stability of blast furnace roof pressure.

The TRT unit is the roof pressure that adopts the adjustable consistent blast furnace of stator blade.This technology can be regulated multiple disturbance, can change the operating turbine line automatically according to the variation of blast furnace gas amount and pressure, maximally utilises whole gas pressure energy, can improve exerting oneself of turbine.The problem that this technology exists is: autocontrol method also needs perfect, and control accuracy needs to improve, and the period needs to reduce.

Owing to causing that the unsettled reason of blast furnace roof pressure is many-sided factor and has uncertainty mostly, and the influence of the variation of roof pressure had non-linear characteristics, therefore when design TRT device, be difficult to prediction in advance, be difficult to provide the measure of guaranteeing stability.And the pressure information that must the time survey according to operation carries out the analytical calculation of aerodynamic force, and carries out automatic control and adjustment.Retrieval shows according to domestic and foreign literature, and with the object of blast furnace gas excess pressure power generating device system as research, the application specific software stove was not reported for work to the proprietary technology method that blast furnace top pressure is controlled to be purpose.

Summary of the invention

Along with the maximization of metallurgy high furnace and the development of modern ironmaking technology, to the stability requirement of blast furnace roof pressure more and more higher (require the furnace top pressure undulating quantity less than ± 2Kpa).Originally the TRT unit was wasted in the reducing valve group or, must guaranteeing that reclaim generated electricity under the stable prerequisite of blast furnace roof pressure more though can reclaim than the pressure energy on Xiao husband fly-ash separator.At present at home and abroad, the great difficult problem of restriction TRT technology popularization application is exactly how further to stablize blast furnace top pressure.When heavy fault, TRT emergency stop particularly took place, how the blast furnace gas with the TRT side switched to former reducing valve group reposefully, will guarantee that simultaneously the roof pressure undulating quantity is controlled at minimum extent in the handoff procedure.

TRT device operational process is flowing and mixing processes such as heat and mass, burning of a complexity, the uncertainty of its structure and parameter, the imperfection of state, and feature such as non-linear, make that the control of TRT device is very difficult, not only require the control strategy of process to have higher precision, and require it to have certain intelligent characteristics.Though fuzzy control has stronger adaptive ability, have certain intelligent control characteristics, its control accuracy depends on the complexity of rule, particularly can't effectively overcome steady-state error.And conventional PID control can't be in harmonious proportion for the uncertain industrial object of plant characteristic and improves response speed and reduce contradiction between the overshoot, but its proportional-plus-integral action is comparatively desirable near the regulating effect among a small circle the trim point, and it is surplus poor finally to eliminate.

The objective of the invention is to, a kind of blast furnace roof pressure stability autocontrol method of blast furnace gas excess pressure power generating device is provided.The present invention is according to fluid mechanics principle, analyze the influence relation between roof pressure and the various complicated factor, this method adopts auto-control software to realize the fluctuation of blast furnace ironmaking process furnace top pressure is controlled in real time automatically, and the calculation control of guaranteeing roof pressure stability software is provided, the present invention includes following content: (1) sets up Equations of Mathematical Physics; (2) ξ calculation of parameter and handoff algorithms; (3) set up automatic control system; (4) according to Equations of Mathematical Physics and expert algorithm establishment control software.

Independently developed control software of the present invention has adopted hybrid Expert Controller (hereinafter to be referred as HEC), HEC has two-layer hierarchical structure, wherein the first layer is the PID controller of routine and common Fuzzy controller, the second layer is the expert systems that typically has knowledge base and inference machine, it is used for finishing two portions function, the first is coordinated two kinds of different control algolithms of subordinate, and it two is self-learning functions of finishing fuzzy rule and pid parameter.The HEC algorithm is divided into and is following several parts: knowledge base, inference machine, feature extraction and Data Base, people-machine interface, Fuzzy controller and PID controller.Below will design respectively at knowledge base and inference machine two major portions.

Hybrid Expert Controller compatibility two kinds of dissimilar common fuzzy (Fuzzy) controllers and conventional proportional integral (PID) setters, and adopted systems approach based on the fluid mechanic model scholarly forecast, make this controller have the functions such as automatic study of the automatic synchronization and the control law of control algolithm, make two classes control algolithm commonly used really reach the effect of learning from other's strong points to offset one's weaknesses like this.Therefore, the applicant adopts a kind of new control algolithm---hybrid expert's control algolithm.The design philosophy of this control algolithm utilization expert systems with uses that combine of Fuzzy control algolithm and conventional pid control algorithm, constitutes one and overlaps complete control algolithm, by emulation and application, has obtained gratifying result.

The present invention can guarantee to satisfy the blast furnace smelting process requirement in the operational process of TRT device, can increase the technology content of product, greatly improves the core competitive of product; Can improve the occupation rate in TRT market, solving the user adopts the TRT technology to worry to influence the worry that blast furnace is produced, solve the calculating and the control techniques difficult problem of this UNSTEADY FLOW, made simulation control in the past be converted into Digital Control, realized the on-line monitoring that furnace roof is pressed in the TRT device.

Description of drawings

When Fig. 1 represents that furnace top pressure P=17kPa switches, the PID controller control process record collection of illustrative plates after STPC software and the optimization;

When Fig. 2 represents that furnace top pressure P=26.5kPa switches, the PID controller control process record collection of illustrative plates after STPC software and the optimization;

When Fig. 3 represents that respectively furnace top pressure P=37.5kPa switches, the PID controller control process record collection of illustrative plates after STPC software and the optimization;

Furnace top pressure crest value result compared collection of illustrative plates when the PID setter control furnace top pressure after Fig. 4 represents STPC software and optimizes was switched;

PID setter control furnace top pressure time length result after Fig. 5 represents STPC software and optimizes is collection of illustrative plates relatively.

Fig. 6 is a TRT device blast furnace roof pressure Stability Control testing apparatus synoptic diagram of the present invention.

Embodiment

The present invention is further illustrated below in conjunction with embodiment that accompanying drawing and contriver provide.Below be the embodiment that the contriver provides.

1. indicators of overall performance

Normal roof pressure undulating quantity ± 0.3kPa～± 0.8kPa

Urgent switching roof pressure undulating quantity ± 0.5kPa～± 1kPa

Switch peak value time 5s～15s

2. main contents and technical scheme

2.1 the know-why that adopts:

Know-why of the present invention is according to fluid mechanics principle, analyze the influence relation between roof pressure and the various complicated factor, a kind of method of quantized control roof pressure stability is proposed, and provide the calculation control of guaranteeing roof pressure stability software, thereby farthest satisfy the blast furnace smelting process requirement in the operational process of assurance TRT device.

2.2 technical scheme

2.2.1 set up Equations of Mathematical Physics

According to analysis, set up following physical mathematics model (system balancing governing equation) to the TRT system.

(1) blast furnace pressure drop equation P _F1-P _F2=ξ _Fρ Q ²/ (2S _F ²)

(2) overall pressure drop equation

$P_B-P_G=({\mathrm{\&xi;}}_F+{\mathrm{\&xi;}}_T+\underset{i=1}{\overset{n}{\mathrm{\&Sigma;}}}\mathrm{\&xi;i})\mathrm{\&rho;}{\mathrm{<figure-callout\; id="2"\; label="Q"\; filenames="A20031010580700192.png"\; state="\{\{state\}\}">Q</figure-callout>}}^2/\left(2{S_B}^2\right)$

(3) gas blower P-Q characteristic equation

P _B＝P(Q)

(4) blower export is to blast furnace blast inlet pressure drop equation

P _B-P _T1＝ξ _HρQ ²/(2S _B ²)

(5) turbine pressure drop equation

P _T1-P _T2＝ξ _TρQ ²/(2S _T ²)

(6) reducing valve by-pass line pressure drop equation

P _C-P _G＝ξ _VρQ ²/(2S _V ²)

(7) turbine stator blades aperture δ _TWith broad sense ratio of damping ξ _TRelational expression

ξ _T=ξ _T(δ _T) or δ _T=δ _T(ξ _T)

(8) the valve opening δ that threads a pipe _VWith valve ratio of damping ξ _VRelational expression

ξ _V=ξ _V(δ _V) or δ _V=δ _V(ξ _V)

(9) state equation of matter

(R) T is a temperature to ρ=ρ in the formula for P, T, and R is a medium parameter.

(10) mass conservation equation G=ρ * Q=cons

(11) differential equation of motion of system's inner fluid:

$\frac{\mathrm{\&rho;}}{g}\mathrm{sl}\frac{\&PartialD;V}{\&PartialD;t}=A{P}_B-A{P}_G-\frac{\mathrm{\&xi;\&rho;A}{\mathrm{<figure-callout\; id="2"\; label="V"\; filenames="A20031010580700192.png"\; state="\{\{state\}\}">V</figure-callout>}}^2}{2g}$

In the above-mentioned system of equations, shown in symbol represent respectively be:

In the formula:

P: pressure (kPa); Q: flow (m ³/ s);

S: sectional area (m ²); T: temperature (K);

ρ: gas density (kg/m ³); ξ: ratio of damping (/);

V: cross section speed (m/s); L: duct length.

δ: aperture (%);

Wherein footmark is represented:

T: turbine;

F: blast furnace; B: gas blower;

G: gas-holder; V: by-pass line;

I: pipeline arbitrary section; 1,2: the turnover cross section;

C: by-pass line and turbine pipeline point of crossing;

H: blower export through hotblast stove to the blast furnace blast inlet;

Above-mentioned system of equations has been explained the relation between flow, pressure drop and the damping in the blast furnace system, is the mathematical description of roof pressure stabilization process.It is the basis of the blast furnace roof pressure stability autocontrol method of blast furnace gas excess pressure power generating device.

2.2.2 ξ calculation of parameter and handoff algorithms

Referring to Fig. 6, blast furnace gas excess pressure power generating device blast furnace roof pressure Stability Control testing apparatus (Fig. 6), medium is under 1 effect of wind regime blower fan, process can produce turbulent bf model subsystem 2, but pipeline 3 and the band contract fully stator blade 4 arranged by band pressure, temperature, flow measurement test measuring point arrive single stage turbine model and power generation assembly (resistance box, automatically controlled) subsystems (generator power 20kW) 5.Reducing valve group 6 is by PV01, PV02, PV03 composes in parallel, but with in parallel by the main gas circuit of being with contract fully stator blade 4 and single stage turbine model and power generation assembly 5 to constitute, realizes mutual switching tests research under 7 effects of automatic control system (containing STPC software, PLC) subsystem.

PV01, PV02, PV03, stator blade, wherein PV01 is identical with the PV03 bore.

Parameter: flow Q, import sectional area S, density p, flow resistance R, resistance coefficient ξ, pressure differential deltap P switches partition ratio λ, aperture K

Fundamental formular: $R=\frac{\mathrm{\&Delta;P}}{Q}$

$\mathrm{\&Delta;P}=\frac{1}{2}{\mathrm{\&rho;\&xi;}\left(\frac{Q}{S}\right)}^2$

Test valve and stator blade characteristic obtain ξ=f (K) curve

Theoretical foundation:

$\mathrm{\&xi;}=\frac{2\mathrm{\&Delta;P}{\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="A20031010580700192.png"\; state="\{\{state\}\}">S</figure-callout>}}^2}{\mathrm{\&rho;}{\mathrm{<figure-callout\; id="2"\; label="Q"\; filenames="A20031010580700192.png"\; state="\{\{state\}\}">Q</figure-callout>}}^2}=\frac{2\mathrm{<figure-callout\; id="2"\; label="R\; S"\; filenames="A20031010580700192.png"\; state="\{\{state\}\}">R</figure-callout>}{S}^{}{}^2}{\mathrm{\&rho;Q}}$

Valve opening is increased to 100% from 0%, obtain ξ=f (K) curve

Tested object: all Self controlling valves and stator blade device

Quick switch test

Parameter before switching: Δ P, Q _T, calculate R _T

Handoff algorithms: Δ P is constant, Q _T=Q ₁+ Q ₂+ Q ₃

Wherein: Q ₂=λ Q _T, recommended value λ=0.7

$Q_1=Q_3=\frac{1-\mathrm{\&lambda;}}{2}{Q}_T$

$\frac{1}{R_T}=\frac{1}{R_1}+\frac{1}{{\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="A20031010580700192.png"\; state="\{\{state\}\}">R</figure-callout>}}_2}+\frac{1}{R_3}$

Calculate: ${\mathrm{<figure-callout\; id="2"\; label="R"\; filenames="A20031010580700192.png"\; state="\{\{state\}\}">R</figure-callout>}}_2=\frac{\mathrm{\&Delta;P}}{\mathrm{\&lambda;}{Q}_T}$

$R_1=R_3=\frac{2\mathrm{\&Delta;P}}{(1-\mathrm{\&lambda;})Q_T}$

Can get thus:

${\mathrm{\&xi;}}_2=\frac{2\mathrm{\&Delta;P}{\mathrm{<figure-callout\; id="2"\; label="S"\; filenames="A20031010580700192.png"\; state="\{\{state\}\}">S</figure-callout>}}_2^2}{\mathrm{\&rho;}{\mathrm{\&lambda;}}^2{\mathrm{<figure-callout\; id="2"\; label="Q\; T"\; filenames="A20031010580700192.png"\; state="\{\{state\}\}">Q</figure-callout>}}_T^{}}$

${\mathrm{\&xi;}}_1={\mathrm{\&xi;}}_3=\frac{8\mathrm{\&Delta;P}{S}_1^2}{{\mathrm{\&rho;}(1-\mathrm{\&lambda;})}^2{\mathrm{<figure-callout\; id="2"\; label="Q\; T"\; filenames="A20031010580700192.png"\; state="\{\{state\}\}">Q</figure-callout>}}_T^{}}$

2.3 automatic control system function of the present invention

2.3.1 Controlling System general introduction

WINCC SCADA software is adopted on the Controlling System upper strata, and bottom adopts SIEMENS S7-300 series of PLC.Grid adopts PROFIBUS DP agreement, connects speed 12MBPS, and key-course adopts the SIEMENSPROFIBUS multiple twin to shield worn-out communication cable, is connected on the PROFIBUS DP bus by the CP342-5 interface module.

2.3.2 SCADA system

The SCADA system adopts the WINCC V5.0 SP2 configuration software of SIEMENS company, runs on WINDOWS 2000 PROFESSIONAL+SP1 platforms.The advantage of this software is that the PLC with SIEMENS company has good compatibility, can integrate easily with the programming software STEP 7 of PLC, improves the development efficiency of system.

2.3.3 PLC system

2.3.3.1 hardware is formed

SIEMENS PLC is adopted in native system data gathering and control.

2.3.3.2 STEP 7 V5.1 software brief introductions

SIEMENS PLC uses STEP 7 software programmings.

2.3.3.3 control software

OB1 (master routine)

FC1 (conversion of IO data)

Finish the scale scale conversion of IO port data, call data block DB1 (IODATA).

FC2 (V01 control/signal takes place and control)

FC3 (signal generator)

FC4 (valve EPSL calculation of parameter)

FC5 (calculation of parameter and switching that TURBINE switches to PV valve group)

FC6 (EPSL parameter → valve opening is calculated)

FC20 (test)

FC21 (test is prepared)

FC22 (valve is opened test)

FC23 (valve is kept)

FC24 (valve closes test)

OB100 (warm start)

FC7 (orifice-plate flowmeter calculation program)

FC8 (fan parameter computation program)

FC9 (blower fan surge protection program)

FC10 (fan efficiency computation program)

Use the independently developed STPC control software of the present invention and adopted hybrid expert's control algolithm (HEC algorithm), it is the design philosophy of utilization expert systems, Fuzzy control algolithm and conventional pid control algorithm are combined use, constitute one and overlap the complete intelligent characteristics algorithm that has.Hybrid Expert Controller (hereinafter to be referred as HEC).HEC is the core of STPC software.Partial differential equation (11) are found the solution, and this blockette is embedded in the sequence of control, formed the characteristics of STPC software.

WINCC SCADA software is adopted on the Controlling System upper strata, and bottom adopts SIEMENS S7-300 series of PLC.The SCADA system adopts the WINCC V5.0 SP2 configuration software of SIEMENS company, runs on WINDOWS 2000 PROFESSIONAL platforms.The advantage of this software is that the PLC with SIEMENS company has good compatibility, can integrate easily with the programming software STEP 7 of PLC, improves the development efficiency of system.

3. test-results explanation

When TRT or generating set unusual condition, must finish coal gas and switch to the reducing valve group branch road in parallel fast with TRT by the turbine branch road.Adopt the STPC control software to be to the testing method of the control effect of this process, under the same conditions relatively its with optimize after PID setter effect that each inherent regulation of furnace top pressure is got.

On the TRT system test set, under identical condition, the STPC software of author's exploitation has very big advantage through comparing with the PID setter (being the control method of the great majority employing of present TRT product) after the optimization, and comparative result is referring to accompanying drawing 1～5.From Fig. 1～4, when condition is identical, STPC software with optimize after PID setter control furnace top pressure result compare furnace top pressure crest value littler (the former be approximately the latter 0.25 times) during switching; From Fig. 5, can obviously find out the time shorter (the former be approximately the latter 0.35 times).

The disturbance that STPC software of the present invention produces when switching than the PID setter after optimizing is little, and " duration of peak value " two indexs all improve a lot, no matter the time length still and when switching the speed of convergence of furnace top pressure crest value faster, and tend towards stability.

Indicators of overall performance compares with domestic and international modern technique

Indicators of overall performance

Normal roof pressure undulating quantity ± 0.3kPa～± 0.8kPa

Urgent switching roof pressure undulating quantity ± 0.5kPa～± 1kPa

Switch peak value time 5s～15s

The blast furnace roof pressure stability autocontrol method of blast furnace gas excess pressure power generating device of the present invention, the calculating and the control techniques difficult problem of this UNSTEADY FLOW have been solved, make simulation control in the past be converted into Digital Control, realized the on-line monitoring that furnace roof is pressed in the TRT device.

Embodiment:

According to technical scheme of the present invention, the applicant has prepared TRT roof pressure stability test research device.Referring to Fig. 6, this blast furnace gas excess pressure power generating device blast furnace roof pressure Stability Control testing apparatus comprises, a wind regime blower fan 1, this wind regime blower fan 1 be by the blower fan stator, fan rotor, and the blower fan transmission group constitutes; This device also comprises with lower member:

One bf model device 2, it is made up of bf model and variable valve v01, and variable valve v01 is arranged on the bf model, and variable valve v01 can produce sine, cosine, square wave, complex wave is in order to realize the various disturbance simulations of blast furnace ironmaking process;

One system pipeline 3 and a plurality of valve module are furnished with the experimental measurement point on the system pipeline, pressure transmitter PT01, PT02, PT03, PT04, PT05 are installed on the experimental measurement point, temperature sensor TT01, TT02, flow sensor FT01; To realize the various states of bf model and blast furnace gas excess pressure power generating device; The bore of system pipeline 3 is DN250.

But a band contract fully stator blade 4, but this band contract fully stator blade by airduct, the contract fully stator blade, deflection cone, YE constitutes; Airduct, contract fully stator blade, two deflection cones have constituted the passage of medium; But YE and transmission rig have constituted the execution unit of contract fully stator blade.

One is connected single stage turbine model and power generation assembly 5 on the system pipeline 3 by valve group parts; This device 5 includes resistance box, electric-controlled parts, and wherein generator power is 20kW.

One reducing valve group 6, reducing valve group 6 is composed in parallel by PV01, PV02, three valves of PV03, PV01 wherein, the bore of PV03 valve equates, is DN100; The bore of PV02 valve is 2 times of PV01, is DN200;

One automatic control system 7; Be connected with above-mentioned each transmitter on the automatic control system 7; WINCC SCADA software is adopted on the automatic control system upper strata, and bottom adopts SIEMENS S7-300 series of PLC; Grid adopts PROFIBUS DP agreement, connects speed 12MBPS, and key-course adopts SIEMENS PROFIBUS multiple twin to shield worn-out communication cable, is connected on the PROFIBUS DP bus by the CP342-5 interface module;

But wind regime blower fan 1, bf model device 2 contract fully stator blades 4, single stage turbine model and power generation assembly 5, reducing valve group 6; Be installed in respectively on the system pipeline 3; Pressure transmitter PT01, temperature sensor TT01 are installed between wind regime blower fan 1 and the bf model device 2, and pressure transmitter PT02, flow sensor FT01 are installed between bf model device 2 and the reducing valve group 6; Temperature sensor TT02, pressure transmitter PT05 are installed between reducing valve group 6 and the blow-off valve; But PT03 and PT04 are installed in the two ends of contract fully stator blade 4.

Medium is under 1 effect of wind regime blower fan, but process can produce turbulent bf model device 2, test pipeline 3 and band contract fully stator blade 4 arrival single stage turbine model and the power generation assemblys 5 that measuring point is arranged by band pressure, temperature, flow measurement; But reducing valve group 6 realizes mutual switching tests with in parallel by the main gas circuit of being with contract fully stator blade 4 and single stage turbine model and power generation assembly 5 to constitute under 7 effects of automatic control system parts.

Automatic control system 7 is used for detecting: source blower fan out temperature T/TH, TT01 and pressure P T01; Top of BF pressure P T01; Flow system flow FT01; Stator blade parts inlet and outlet pressure PT03 and PT04; System's emptying place temperature and pressure TT02 and PT05.Detected data enter PLC and computer through transmitter, realize functions such as Data Detection, control, record, analysis.

Roof pressure Calculation on stability control software (being called for short STPC software) is installed in the automatic control system 7, and roof pressure Calculation on stability control software of the present invention has following basic function:

(1) when turbine normally moves, exceed given amplitude as the undulating quantity of roof pressure, software will provide the execution command of regulating turbine stator blades aperture quantized value rapidly, and guarantees to make furnace top pressure return to normal range in the given time.

(2) when the turbine orderly closedown or when needing emergency stop; software will be behind stop instruction; according to orderly closedown or the requirement of emergency stop program; provide and close turbine pipeline air intake valve; and follow procedure requires to provide the execution command of opening by-pass line reducing valve aperture quantized value, guarantees to make in preset time furnace top pressure to keep in the normal range.

(3) after software obtains the turbine start-up command, will provide the execution command of opening turbine intake ducting valve and closing by-pass line pressure loading valve quantized value according to the requirement of start schedule of operation, ensure the stability of furnace top pressure in the turbine start process.

(4) control software will adopt hybrid expert's control algolithm, can regulate the knowledge base of roof pressure stability accumulation according to the TRT operation, the controlled variable in the continuous revision program, and this software is long more duration of service, and the effect of control is good more.That is to say that the undulating quantity index of control roof pressure and fluctuation duration of peak value index will improve along with TRT working time.

Claims (2)

1. the blast furnace roof pressure of blast furnace gas excess pressure power generating device stability autocontrol method adopts auto-control software to realize the automatic in real time control of the fluctuation of blast furnace ironmaking process furnace top pressure be is characterized in that, may further comprise the steps:

1) sets up Equations of Mathematical Physics

According to analysis, set up the system balancing governing equation to the TRT system:

(1) blast furnace pressure drop equation

P _F1-P _F2＝ξ _FρQ ²/(2S _F ²)

(2) overall pressure drop equation

$P_B-P_G=({\mathrm{\&xi;}}_F+{\mathrm{\&xi;}}_T+\underset{i=1}{\overset{n}{\mathrm{\&Sigma;}}}\mathrm{\&xi;i}){\mathrm{\&rho;Q}}^2/\left({2S_B}^2\right)$

(3) gas blower P-Q characteristic equation

P _B＝P(Q)

(4) blower export is to blast furnace blast inlet pressure drop equation

P _B-P _T1＝ξ _HρQ ²/(2S _B ²)

(5) turbine pressure drop equation

P _T1-P _T2＝ξ _TρQ ²/(2S _T ²)

(6) reducing valve by-pass line pressure drop equation

P _C-P _G＝ξ _vρQ ²/(2S _v ²)

(7) turbine stator blades aperture δ _TWith broad sense ratio of damping ξ _TRelational expression

ξ _T=ξ _T(δ _T) or δ _T=δ _T(ξ _T)

(8) the valve opening δ that threads a pipe _VWith valve ratio of damping ξ _vRelational expression

ξ _V=ξ _v(δ _V) or δ _V=δ _V(ξ _V)

(9) state equation of matter

(R) T is a temperature to ρ=ρ in the formula for P, T, and R is a medium parameter;

(10) mass conservation equation

G＝ρ*Q＝cons

(11) differential equation of motion of system's inner fluid: $\frac{\mathrm{\&rho;}}{g}\mathrm{sl}\frac{\&PartialD;V}{\&PartialD;t}={\mathrm{AP}}_B-{\mathrm{AP}}_G-\frac{\mathrm{\&xi;\&rho;A}{V}^2}{2g}$

Above-mentioned system of equations has been explained the relation between flow, pressure drop and the damping in the blast furnace system; It is the mathematical description of roof pressure stabilization process;

In the above-mentioned system of equations, what symbol was represented respectively shown in the formula is:

P: pressure (kPa) Q: flow (m ³/ s);

S: sectional area (m ²); T: temperature (K);

ρ: gas density (kg/m ³); ξ: ratio of damping (/);

V: cross section speed (m/s); L: duct length.

δ: aperture (%);

Wherein footmark is represented:

T: turbine;

F: blast furnace; B: gas blower;

G: gas-holder; V: by-pass line;

I: pipeline arbitrary section; 1,2: the turnover cross section;

C: by-pass line and turbine pipeline point of crossing;

H: blower export through hotblast stove to the blast furnace blast inlet;

2) ξ calculation of parameter and handoff algorithms

Controlling System is formed: PV01, and PV02, PV03, stator blade, wherein PV01 is identical with the PV03 bore;

PV01, PV02, PV03 represent three valves of the reducing valve group in parallel with the TRT branch road respectively;

Parameter: flow Q, import sectional area S, density p, flow resistance R, resistance coefficient ξ, pressure differential deltap P switches partition ratio λ, aperture K;

Fundamental formular: $R=\frac{\mathrm{\&Delta;P}}{Q}$

$\mathrm{\&Delta;P}=\frac{1}{2}\mathrm{\&rho;\&xi;}{\left(\frac{Q}{S}\right)}^2$

Test valve and stator blade characteristic obtain ξ=f (K) curve

Theoretical foundation: $\mathrm{\&xi;}=\frac{{2\mathrm{\&Delta;PS}}^2}{{\mathrm{\&rho;Q}}^2}=\frac{{2\mathrm{RS}}^2}{\mathrm{\&rho;Q}}$

Valve opening is increased to 100% from 0%, obtain ξ=f (K) curve

Tested object: all Self controlling valves and stator blade device

Quick switch test

Parameter before switching: Δ P, Q _T, calculate R _T

Handoff algorithms: Δ P is constant, Q _T=Q ₁+ Q ₂+ Q ₃

Wherein: Q ₂=λ Q _T, recommended value λ=0.7

$Q_1=Q_3=\frac{1-\mathrm{\&lambda;}}{2}{Q}_T$

$\frac{1}{R_T}=\frac{1}{R_1}+\frac{1}{R_2}+\frac{1}{R_3}$

Calculate: $R_2=\frac{\mathrm{\&Delta;P}}{{\mathrm{\&lambda;Q}}_T}$

$R_1=R_3=\frac{2\mathrm{\&Delta;P}}{(1-\mathrm{\&lambda;})Q_T}$

Can get thus:

${\mathrm{\&xi;}}_2=\frac{2\mathrm{\&Delta;}{\mathrm{PS}}_2^2}{{\mathrm{\&rho;\&lambda;}}^2{Q}_T^2}$

${\mathrm{\&xi;}}_1={\mathrm{\&xi;}}_3=\frac{8\mathrm{\&Delta;}{\mathrm{PS}}_1^2}{\mathrm{\&rho;}{(1-\mathrm{\&lambda;})}^2{Q}_T^2}$

3) auto-control software system

WINCC SCADA software system are adopted on the Controlling System upper strata, and bottom adopts SIEMENS S7-300 series of PLC; Grid adopts PROFIBUS DP agreement, connect speed 12MBPS, key-course adopts SIEMENS PROFIBUS multiple twin to shield worn-out communication cable, be connected on the PROFIBUS DP bus by the CP342-5 interface module, the blast furnace roof pressure stability that constitutes blast furnace gas excess pressure power generating device is controlled special software automatically.

2. the blast furnace roof pressure of blast furnace gas excess pressure power generating device as claimed in claim 1 stability autocontrol method is characterized in that, described auto-control software system possesses following function:

(1) when turbine normally moves, the undulating quantity of roof pressure exceeds given amplitude, and software will provide the execution command of regulating turbine stator blades aperture quantized value rapidly, and guarantees to make furnace top pressure return to normal range in the given time;

(2) when the turbine orderly closedown or when needing emergency stop, software will be behind stop instruction, according to orderly closedown or the requirement of emergency stop program, provide and close turbine pipeline air intake valve, and follow procedure requires to provide the execution command of opening by-pass line reducing valve aperture quantized value, guarantees to make in preset time furnace top pressure to keep in the normal range;

(3) after software obtains the turbine start-up command, will provide the execution command of opening turbine intake ducting valve and closing by-pass line pressure loading valve quantized value according to the requirement of start schedule of operation, ensure the stability of furnace top pressure in the turbine start process;

(4) control software will adopt hybrid expert's control algolithm, can regulate the knowledge base of roof pressure stability accumulation according to the TRT operation, controlled variable in the continuous revision program, this software is long more duration of service, the effect of control is good more, and the undulating quantity index of control roof pressure and fluctuation duration of peak value index will improve along with TRT working time.

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