CN103605329B - Components of thermoelectric generator set accumulation low-cycle fatigue life loss method for supervising - Google Patents

Abstract

The present invention relates to a kind of accumulation low-cycle fatigue life loss in-service monitoring and control method of thermal power generation unit vitals, it is characterized in that, step is: read the online measuring point data of thermal power generation unit; Calculate the thermal stress of vitals; Calculate the mechanical stress of vitals; Calculate the compound stress of vitals; Calculate the equivalent stress of vitals; Determine the maximum stress of three compound stresses; Determine the minimum stress of three compound stresses; Calculate the real number field equivalent stress of vitals; Divide the stress period with same sign; Determine σ _ijthe peak stress etc. of>=0 period.Advantage of the present invention there is provided the in-service monitoring of the accumulation low-cycle fatigue life loss of thermal power generation unit vitals and control device and method, achieves the online calculation and control of the accumulation low-cycle fatigue life loss of one or more thermal power generation unit vitals of fuel-burning power plant.

Description

Components of thermoelectric generator set accumulation low-cycle fatigue life loss method for supervising

Technical field

The present invention relates to a kind of accumulation low-cycle fatigue life loss in-service monitoring and control method of thermal power generation unit vitals, belong to thermoelectric generator technical group field.

Background technology

The vitals of the thermal power generation unit being dominant failure mode with low-cycle fatigue damage has: high pressure rotor, middle pressure rotor, low pressure rotor, high-pressure inner cylinder, IP inner casing, hp outer cylinder, main steam valve, high voltage adjusting valve casing, generator amature, generator guard ring, drum, steam-water separator, high temperature header, low temperature header, main steam line, reheaing steam pipe etc.These vitals sizes are large, involve great expense, and the consequence of fatigue breakdown is serious.In the startup of thermal power generation unit, shutdown and load change process; in the vitals of thermal power generation unit; because radially temperature distributing disproportionation is even and produce larger thermal stress, the transient-state low-cycle fatigue life loss of thermal power generation unit vitals is caused to increase.Within the military service phase of thermal power generation unit, the long transient-state low-cycle fatigue life loss increase of vitals must cause its accumulation low-cycle fatigue life loss to increase.If accumulation low-cycle fatigue life loss supervisory and control is improper, the low-cycle fatigue of thermal power generation unit vitals can be caused to damage, engineering is badly in need of the accumulation low-cycle fatigue life loss in-service monitoring of thermal power generation unit vitals and control device and method.

Applicant applies for a patent " a kind of method and system of on-line monitoring steam turbine roter low-cycle fatigue life consumption ", and application number is 200710039898.3, " low cycle fatigue life consumption of components of steam turbine in-service monitoring and control device and method " application number is 200910050273.6, " rotor end bell low-cycle fatigue life loss in-service monitoring and control device and method " application number be 200910201405.0 and " transient-state low-cycle fatigue life loss of pressure-containing member outside boiler in-service monitoring and control device and method " application number be 201010102187.8, and the Fatigue Life Expenditure online management technology of open source literature report, all that in-service monitoring and control are carried out to the transient-state low-cycle fatigue life of genset vitals, and the supervisory and control of the accumulation low-cycle fatigue life loss of thermal power generation unit vitals, also do not have suitable apparatus and method available.

Summary of the invention

The object of this invention is to provide a kind of accumulation low-cycle fatigue life loss in-service monitoring and control method of thermal power generation unit vitals, realize in-service monitoring and the control of the accumulation low-cycle fatigue life loss of 2 to 16 vitals of one, a fuel-burning power plant or several thermal power generation unit.

In order to solve the problems of the technologies described above, technical scheme of the present invention there is provided a kind of accumulation low-cycle fatigue life loss in-service monitoring and control method of thermal power generation unit vitals, it is characterized in that, C language is adopted to write the computer software of the accumulation low-cycle fatigue life loss of thermal power generation unit vitals, operate in accumulation low-cycle fatigue life loss on calculation server, be applied to accumulation low-cycle fatigue life loss in-service monitoring and the control of thermal power generation unit vitals, its concrete steps are:

The first step, the online measuring point data of reading thermal power generation unit:

Database server minute to 5 minutes, reads main steam pressure by plant level supervisory information system from the scattered control system of thermal power generation unit and online measuring point every Δ τ=0.1, main steam temperature, reheated steam pressure, reheat steam temperature, vapor pressure after governing stage, vapor (steam) temperature after governing stage, one steam pumping pressure, one steam pumping temperature, high row's vapor pressure, high row's vapor (steam) temperature, middle row's vapor pressure, middle row's vapor (steam) temperature, high-pressure inner cylinder metal temperature, IP inner casing metal temperature, five steam pumping pressure, five steam pumping temperature, six steam pumping pressure, six steam pumping temperature, seven steam pumping pressure, eight steam pumping pressure, turbine speed, power, condenser pressure, feed pressure, feed temperature, generator active power, power factor, three-phase current and voltage, exciting current, cold hydrogen temperature and hot hydrogen temperature, the wall temperature measurement point numerical value of boiler drum, the wall temperature measurement point numerical value of steam-water separator, the wall temperature measurement point numerical value of high temperature header, the wall temperature measurement point numerical value of low temperature header, the wall temperature measurement point numerical value of main steam line, the wall temperature measurement point numerical value of reheaing steam pipe,

The thermal stress of second step, calculating vitals:

For the data variation of the online measuring point of fiery thermal power generation unit, adopt existing simplified model, at the temperature field of line computation i-th thermal power generation unit jth vitals and tangential thermal stress σ _{θ thij}, radial thermal stress σ _rthijwith Axial Thermal stress σ _zthij;

The mechanical stress of the 3rd step, calculating vitals:

For the data variation of the online measuring point of fiery thermal power generation unit, adopt existing simplified model, the tangential mechanical stress σ that online meter i-th thermal power generation unit jth vitals causes due to working medium pressure or working speed _{θ mchij}, radial mechanical stress σ _rmchijwith axial mechanical stress σ _zmchij;

The compound stress of the 4th step, calculating vitals:

According to the following formula, at the compound tangential stress σ of line computation i-th thermal power generation unit jth vitals _{θ ij}, compound radial stress σ _rijwith compound axial stress σ _zij:

σ _θij＝σ _θthij+σ _θmchij；

σ _rij＝σ _rthij+σ _rmchij；

σ _zij＝σ _zthij+σ _zmchij；

The equivalent stress of the 5th step, calculating vitals:

The online computing formula of the equivalent stress of i-th thermal power generation unit jth vitals is:

${\mathrm{\σ}}_{\mathrm{eqij}}={\left[\frac{{({\mathrm{\σ}}_{\mathrm{\θij}}-{\mathrm{\σ}}_{\mathrm{rij}})}^2+{({\mathrm{\σ}}_{\mathrm{rij}}-{\mathrm{\σ}}_{\mathrm{zij}})}^2+{({\mathrm{\σ}}_{\mathrm{zij}}-{\mathrm{\σ}}_{\mathrm{\θij}})}^2}{2}\right]}^{\frac{1}{2}};$

6th step, determine the maximum stress of three compound stresses:

In three compound stresses of i-th thermal power generation unit jth vitals, determine maximum stress σ _maxonline computing formula be:

σ _max＝max(σ _θij，σ _rij，σ _zij)；

7th step, determine the minimum stress of three compound stresses:

In three compound stresses of i-th thermal power generation unit jth vitals, determine minimum stress σ _minonline computing formula be:

σ _min＝min(σ _θij，σ _rij，σ _zij)；

The real number field equivalent stress of the 8th step, calculating vitals:

The online computing formula of the real number field equivalent stress of i-th thermal power generation unit jth vitals is:

σ _ij＝σ _eqij×sign(σ _max+σ _min)；

In formula, sign (σ _max+ σ _min) be sign function, if (σ _max+ σ _min)>=0, then sign (σ _max+ σ _min)=1; If (σ _max+ σ _min) <0, then sign (σ _max+ σ _min)=-1;

9th step, division have the stress period of same sign:

For i-th thermal power generation unit jth vitals real number field equivalent stress σ _ijonline result of calculation, according to real number field equivalent stress σ _iipositive number and the changing moment of negative, real number field equivalent stress σ _ijthe historical data of online result of calculation, according to the time sequencing of in-service monitoring, divides into σ _ij>=0 period and σ _ijthe <0 period;

Tenth step, determine σ _ijthe peak stress of>=0 period:

In a certain period, there is the n of i-th thermal power generation unit jth vitals ₁individual real number field equivalent stress σ _ijall be more than or equal to 0, then the peak stress σ of this period i-th thermal power generation unit jth vitals _ijponline computing formula be:

σ _ijp＝max(σ _ij1，σ _ij2，…，σ _ijn1)；

11 step, determine σ _ijthe peak stress σ of <0 period _ijp:

In another period, there is the n of i-th thermal power generation unit jth vitals ₂individual real number field equivalent stress σ _ijall be less than 0, then the peak stress σ of this period i-th thermal power generation unit jth vitals _ijponline computing formula be:

σ _ijp＝max(|σ _ij1|，|σ _ij2|，…，|σ _ijn2|)；

12 step, the low-cycle fatigue strain amplitude that calculating vitals peak stress is corresponding:

Adopt following formula, calculate the low-cycle fatigue strain amplitude ε of symmetrical fatigue and cyclic corresponding to an i platform thermal power generation unit jth vitals peak stress _aii:

ε _aij＝(1+μ)σ _ijp／(1.5E)；

In formula, μ is the Poisson ratio of material under i-th thermal power generation unit jth vitals working temperature, and E is the elastic modulus of material under i-th thermal power generation unit jth vitals working temperature;

13 step, the low-cycle fatigue life that calculating vitals peak stress is corresponding:

Adopt prior art, use the low-cycle fatigue curve ε of vitals material _aij=F (N _fij), calculate 1 time every Δ τ, draw the low-cycle fatigue life N of i-th thermal power generation unit jth symmetrical cycle that vitals peak stress is corresponding _fij;

14 step, the transient-state low-cycle fatigue life loss that calculating vitals peak stress is corresponding:

Adopt following formula, at the transient-state low-cycle fatigue life loss d that the peak stress of line computation i-th thermal power generation unit jth vitals is corresponding _ijp:

d _ijp＝(2N _fij) ^-1×100％；

The accumulation low-cycle fatigue life loss of the 15 step, calculating vitals:

The accumulation low-cycle fatigue life loss E of i-th thermal power generation unit jth vitals _nijonline computing formula be expressed as:

E _Nij＝E _Nij0+d _ijp；

In formula, E _nij0be that i-th thermal power generation unit jth vitals adds up the accumulation low-cycle fatigue life loss calculated after transient-state low-cycle fatigue life loss corresponding to previous peak stress;

16 step, determine the maximal value of the accumulation low-cycle fatigue life loss of i-th unit:

In m vitals of i-th thermal power generation unit, the maximal value E of accumulation low-cycle fatigue life loss _nmaxionline computing formula be expressed as:

E _Nmaxi＝max(E _Ni1，E _Ni2，…，E _Nim)；

The calendar life loss permissible value of the 17 step, calculating i-th unit:

The calendar life loss permissible value [E] of i-th thermal power generation unit of being on active service within the design phase in longevity _ionline computing formula be expressed as:

The accumulation low-cycle fatigue life loss margin of safety of the 18 step, calculating i-th unit:

The accumulation low-cycle fatigue life loss margin of safety Δ E of i-th thermal power generation unit _ionline computing formula be expressed as:

ΔE _i＝0.75×[E] _i-E _Nmaxi-0.25；

At accumulation low-cycle fatigue life loss margin of safety Δ E _ion the right side of the equal sign of computing formula 0.75 [E] _i, represent that life consumption leaves the safe clearance of 0.25, in order to the creep life consumption of high-temperature component and other life consumptions of low-temperature components;

The optimal control of the 19 step, i-th unit accumulation low-cycle fatigue life loss:

I-th thermal power generation unit accumulation low-cycle fatigue life loss is controlled by level of factory monitor message device and thermal power generation unit distributed control apparatus:

(1) if 0< Δ E _i<0.1, show that the accumulation low-cycle fatigue life loss of i-th thermal power generation unit vitals is in slave mode, the optimal control measure of recommendation provides the regulation main steam temperature rate of change of " products instruction " and the numerical value of load changing rate to carry out the startup of unit, shutdown and load change according to thermal power generation unit manufacturing enterprise;

(2) if Δ E _i>=0.1, show that the accumulation low-cycle fatigue life loss margin of safety of i-th thermal power generation unit vitals is large, the optimal control measure recommended increases main steam temperature rate of change and load changing rate to carry out the startup of unit, shutdown and load change, the regulation main steam temperature rate of change of " products instruction " that increase amplitude provides for thermal power generation unit manufacturing enterprise and the former numerical value of load changing rate 0.1 ~ 0.3 times, with the residual life of this thermal power generation unit of reasonable employment;

(3) if Δ E _i≤ 0, show that the accumulation low-cycle fatigue life loss margin of safety of i-th thermal power generation unit is little and accumulation low-cycle fatigue life loss is large, suggestion reduces main steam temperature rate of change and load changing rate and carries out the startup of unit, shutdown and load change, the regulation main steam temperature rate of change of " products instruction " that minimizing amplitude provides for thermal power generation unit manufacturing enterprise and the former numerical value of load changing rate 0.2 ~ 0.6 times, to extend the serviceable life of this thermal power generation unit;

The optimal control of the 20 step, level of factory multiple stage unit accumulation low-cycle fatigue life loss:

The accumulation low-cycle fatigue life loss margin of safety Δ E of level of factory multiple stage thermal power generation unit _isort from small to large, according to Δ E _ithe size optimizing operation that carries out level of factory multiple stage thermal power generation unit control, the Optimized Operation grown by level of factory monitor message device and operation department value controls i-th thermal power generation unit accumulation low-cycle fatigue life loss:

(1) if Δ E _ithe little accumulation low-cycle fatigue life loss showing this thermal power generation unit is large, accumulation low-cycle fatigue life loss margin of safety is little, residual life is short, the optimal control measure recommended is multi-band basic load, participates in peak regulation less, to extend the serviceable life of this thermal power generation unit;

(2) if Δ E _ishow that greatly the accumulation low-cycle fatigue life loss of this thermal power generation unit is little, accumulation low-cycle fatigue life loss margin of safety is large, residual life is long, more the optimal control measure recommended participates in peak regulation, with the residual life of this thermal power generation unit of reasonable employment;

21 step, printout result:

The online result of calculation of accumulation low-cycle fatigue life loss of printout thermal power generation unit vitals and control measure as required, the optimizing operation being applied to thermal power generation unit controls.

Advantage of the present invention there is provided the in-service monitoring of the accumulation low-cycle fatigue life loss of thermal power generation unit vitals and control device and method, achieves the online calculation and control of the accumulation low-cycle fatigue life loss of one or more thermal power generation unit vitals of fuel-burning power plant.If when the accumulation low-cycle fatigue life loss of separate unit thermal power generation unit vitals is bigger than normal, controls accumulation low-cycle fatigue life loss by the numerical value of this steam system of thermal power plant rate of temperature change of on line real time control and load changing rate and increase fast.For multiple stage thermal power generation unit, by the optimal control of the accumulation low-cycle fatigue life loss of level of factory multiple stage unit vitals, the large thermal power generation unit many participations peak regulation of accumulation low-cycle fatigue life loss margin of safety Δ Ei and the little thermal power generation unit of accumulation low-cycle fatigue life loss margin of safety Δ Ei is adopted to participate in the control measure of peak regulation less, the accumulation low-cycle fatigue life of level of factory multiple stage thermal power generation unit is made to be in slave mode, reach the technique effect using the accumulation low-cycle fatigue life loss control device of a set of vitals to carry out the accumulation low-cycle fatigue life loss of a supervisory and control multiple vitals of one or more thermal power generation unit of fuel-burning power plant, reach the technique effect being ensured the safe operation of thermal power generation unit vitals long period by in-service monitoring and the accumulation low-cycle fatigue life loss controlling thermal power generation unit vitals.

Accompanying drawing explanation

Fig. 1 is the block scheme of in-service monitoring of the present invention and control device;

Fig. 2 adopts by the present invention the flow process of method;

The computer software block diagram that Fig. 3 adopts for the online calculation server of accumulation low-cycle fatigue life loss of the present invention;

Fig. 4 is the schematic diagram of the accumulation low-cycle fatigue life loss result of calculation of thermal power generation unit vitals.

Embodiment

For making the present invention become apparent, hereby with preferred embodiment, and accompanying drawing is coordinated to be described in detail below.

As shown in Figure 1, for the block scheme of in-service monitoring of the present invention and control device, the accumulation low-cycle fatigue life loss in-service monitoring of described thermal power generation unit vitals and control device are by the online calculation server of two redundancy accumulation low-cycle fatigue life loss, two redundant database server and plant level supervisory information system (SIS system) composition, the online calculation server of accumulation low-cycle fatigue life loss is connected with database server, database server is connected by the scattered control system (DCS) of plant level supervisory information system and thermal power generation unit and online measuring point.

As shown in Figure 2, adopt by the present invention the process flow diagram of method, as shown in Figure 3, for the computer software block diagram that the online calculation server of accumulation low-cycle fatigue life loss of the present invention adopts, this software is arranged on the online calculation server of accumulation low-cycle fatigue life loss of thermal power generation unit vitals, is applied to the online calculation and control of 3 thermal power generation unit multiple vitals moral accumulation low-cycle fatigue life loss.

Present invention also offers accumulation low-cycle fatigue life loss in-service monitoring and the control method of the thermal power generation unit vitals that a kind of said apparatus adopts, C language is adopted to write the computer software of the accumulation low-cycle fatigue life loss of thermal power generation unit vitals, operate in accumulation low-cycle fatigue life loss on calculation server, be applied to accumulation low-cycle fatigue life loss in-service monitoring and the control of thermal power generation unit vitals, its concrete steps are:

The first step, the online measuring point data of reading thermal power generation unit:

Database server minute to 5 minutes, reads main steam pressure by plant level supervisory information system from the scattered control system of thermal power generation unit and online measuring point every Δ τ=0.1, main steam temperature, reheated steam pressure, reheat steam temperature, vapor pressure after governing stage, vapor (steam) temperature after governing stage, one steam pumping pressure, one steam pumping temperature, high row's vapor pressure, high row's vapor (steam) temperature, middle row's vapor pressure, middle row's vapor (steam) temperature, high-pressure inner cylinder metal temperature, IP inner casing metal temperature, five steam pumping pressure, five steam pumping temperature, six steam pumping pressure, six steam pumping temperature, seven steam pumping pressure, eight steam pumping pressure, turbine speed, power, condenser pressure, feed pressure, feed temperature, generator active power, power factor, three-phase current and voltage, exciting current, cold hydrogen temperature and hot hydrogen temperature, the wall temperature measurement point numerical value of boiler drum, the wall temperature measurement point numerical value of steam-water separator, the wall temperature measurement point numerical value of high temperature header, the wall temperature measurement point numerical value of low temperature header, the wall temperature measurement point numerical value of main steam line, the wall temperature measurement point numerical value of reheaing steam pipe,

The thermal stress of second step, calculating vitals:

For the data variation of the online measuring point such as pressure, temperature, parts wall temperature of the rotating speed of fiery thermal power generation unit and power, steam or hydrogen, the simplified models such as the thick cyclinder model of employing prior art or cylinder model, at the temperature field of line computation i-th thermal power generation unit jth vitals and tangential thermal stress σ _{θ thij}, radial thermal stress σ _rthijwith Axial Thermal stress σ _zthij;

The mechanical stress of the 3rd step, calculating vitals:

For the data variation of the online measuring point such as pressure, temperature, parts wall temperature of the rotating speed of fiery thermal power generation unit and power, steam or hydrogen, the simplified models such as the thick cyclinder model of employing prior art or cylinder model, the tangential mechanical stress σ that online meter i-th thermal power generation unit jth vitals causes due to working medium pressure or working speed _{θ mchij}, radial mechanical stress σ _rmchijwith axial mechanical stress σ _zmchij;

The compound stress of the 4th step, calculating vitals:

According to the following formula, at the compound tangential stress σ of line computation i-th thermal power generation unit jth vitals _{θ ij}, compound radial stress σ _rijwith compound axial stress σ _zij:

σ _θij＝σ _θthij+σ _θmchij；

σ _rij＝σ _rthij+σ _rmchij；

σ _zij＝σ _zthij+σ _zmchij；

The equivalent stress of the 5th step, calculating vitals:

The online computing formula of the equivalent stress of i-th thermal power generation unit jth vitals is:

${\mathrm{\&sigma;}}_{\mathrm{eqij}}={\left[\frac{{({\mathrm{\&sigma;}}_{\mathrm{\&theta;ij}}-{\mathrm{\&sigma;}}_{\mathrm{rij}})}^2+{({\mathrm{\&sigma;}}_{\mathrm{rij}}-{\mathrm{\&sigma;}}_{\mathrm{zij}})}^2+{({\mathrm{\&sigma;}}_{\mathrm{zij}}-{\mathrm{\&sigma;}}_{\mathrm{\&theta;ij}})}^2}{2}\right]}^{\frac{1}{2}};$

6th step, determine the maximum stress of three compound stresses:

In three compound stresses of i-th thermal power generation unit jth vitals, determine maximum stress σ _maxonline computing formula be:

σ _max＝max(σ _θij，σ _rij，σ _zij)；

7th step, determine the minimum stress of three compound stresses:

In three compound stresses of i-th thermal power generation unit jth vitals, determine minimum stress σ _minonline computing formula be:

σ _min＝min(σ _θij，σ _rij，σ _zij)；

The real number field equivalent stress of the 8th step, calculating vitals:

The online computing formula of the real number field equivalent stress of i-th thermal power generation unit jth vitals is;

σ _ij＝σ _eqij×sign(σ _max+σ _min)；

In formula, sign (σ _max+ σ _min) be sign function, if (σ _max+ σ _min) >0, then sign (σ _max+ σ _min)=1; If (σ _max+ σ _min) <0, then sign (σ _max+ σ _min)=-1;

9th step, division have the stress period of same sign:

For i-th thermal power generation unit jth vitals real number field equivalent stress σ _ijonline result of calculation, according to real number field equivalent stress σ _ijpositive number and the changing moment of negative, real number field equivalent stress σ _ijthe historical data of online result of calculation, according to the time sequencing of in-service monitoring, divides into σ _ij>=0 period and σ _ijthe <0 period;

Tenth step, determine σ _ijthe peak stress of>=0 period:

In a certain period, there is the n of i-th thermal power generation unit jth vitals ₁individual real number field equivalent stress σ _ijall be more than or equal to 0, then the peak stress σ of this period i-th thermal power generation unit jth vitals _ijponline computing formula be:

σ _ijp＝max(σ _ij1，σ _ij2，…，σ _ijn1)；

11 step, determine σ _ijthe peak stress σ of <0 period _ijp:

In another period, there is the n of i-th thermal power generation unit jth vitals ₂individual real number field equivalent stress σ _ijall be less than 0, then the peak stress σ of this period i-th thermal power generation unit jth vitals _ijponline computing formula be:

σ _ijp＝max(|σ _ij1|，|σ _ij2|，…，|σ _ijn2|)；

12 step, the low-cycle fatigue strain amplitude that calculating vitals peak stress is corresponding:

Adopt the low-cycle fatigue strain amplitude ε of the symmetrical fatigue and cyclic that a following formulae discovery i platform thermal power generation unit jth vitals peak stress is corresponding _aij:

ε _aij＝(1+μ)σ _ijp／(1.5E)

In formula, μ is the Poisson ratio of material under i-th thermal power generation unit jth vitals working temperature, and E is the elastic modulus of material under i-th thermal power generation unit jth vitals working temperature;

13 step, the low-cycle fatigue life that calculating vitals peak stress is corresponding:

Adopt prior art, use the low-cycle fatigue curve ε of vitals material _aij=F (N _fij), calculate 1 time every Δ τ, draw the low-cycle fatigue life N of i-th thermal power generation unit jth symmetrical cycle that vitals peak stress is corresponding _fij;

14 step, the transient-state low-cycle fatigue life loss that calculating vitals peak stress is corresponding:

Adopt following formula, at the transient-state low-cycle fatigue life loss d that the peak stress of line computation i-th thermal power generation unit jth vitals is corresponding _ijp:

d _ijp＝(2N _fij) ^-1×100％：

The accumulation low-cycle fatigue life loss of the 15 step, calculating vitals:

The accumulation low-cycle fatigue life loss E of i-th thermal power generation unit jth vitals _nijonline computing formula be expressed as:

E _Nij＝E _Nij0+d _ijp；

In formula, E _nij0be that i-th thermal power generation unit jth vitals adds up the accumulation low-cycle fatigue life loss calculated after transient-state low-cycle fatigue life loss corresponding to previous peak stress;

16 step: the maximal value determining the accumulation low-cycle fatigue life loss of i-th unit:

In m vitals of i-th thermal power generation unit, the maximal value E of accumulation low-cycle fatigue life loss _nmaxionline computing formula be expressed as:

E _Nmaxi＝max(E _Ni1，E _Ni2，…，E _Nim)；

The calendar life loss permissible value of the 17 step, calculating i-th unit:

The calendar life loss permissible value [E] of i-th thermal power generation unit of being on active service within the design phase in longevity _ionline computing formula be expressed as:

The accumulation low-cycle fatigue life loss margin of safety of the 18 step, calculating i-th unit:

The accumulation low-cycle fatigue life loss margin of safety Δ E of i-th thermal power generation unit _ionline computing formula be expressed as:

ΔE _i＝0.75×[E] _i-E _Nmaxi-0.25；

At accumulation low-cycle fatigue life loss margin of safety Δ E _ion the right side of the equal sign of computing formula 0.75 [E] _i, represent that life consumption leaves the safe clearance of 0.25, in order to the creep life consumption of high-temperature component and other life consumptions of low-temperature components;

The optimal control of the 19 step, i-th unit accumulation low-cycle fatigue life loss:

I-th thermal power generation unit accumulation low-cycle fatigue life loss is controlled by level of factory monitor message device and thermal power generation unit distributed control apparatus:

(1) if 0< Δ E _i<0.1, show that the accumulation low-cycle fatigue life loss of i-th thermal power generation unit vitals is in slave mode, the optimal control measure of recommendation provides the regulation main steam temperature rate of change of " products instruction " and the numerical value of load changing rate to carry out the startup of unit, shutdown and load change according to thermal power generation unit manufacturing enterprise;

(2) if Δ E _i>=0.1, show that the accumulation low-cycle fatigue life loss margin of safety of i-th thermal power generation unit vitals is large, the optimal control measure recommended increases main steam temperature rate of change and load changing rate to carry out the startup of unit, shutdown and load change, the regulation main steam temperature rate of change of " products instruction " that increase amplitude provides for thermal power generation unit manufacturing enterprise and the former numerical value of load changing rate 0.1 ~ 0.3 times, with the residual life of this thermal power generation unit of reasonable employment;

(3) if Δ E _i≤ 0, show that the accumulation low-cycle fatigue life loss margin of safety of i-th thermal power generation unit is little and accumulation low-cycle fatigue life loss is large, suggestion reduces main steam temperature rate of change and load changing rate and carries out the startup of unit, shutdown and load change, the regulation main steam temperature rate of change of " products instruction " that minimizing amplitude provides for thermal power generation unit manufacturing enterprise and the former numerical value of load changing rate 0.2 ~ 0.6 times, to extend the serviceable life of this thermal power generation unit;

20 step: the optimal control of level of factory multiple stage unit accumulation low-cycle fatigue life loss:

The accumulation low-cycle fatigue life loss margin of safety Δ E of level of factory multiple stage thermal power generation unit _isort from small to large, according to Δ E _ithe size optimizing operation that carries out level of factory multiple stage thermal power generation unit control, the Optimized Operation grown by level of factory monitor message device and operation department value controls i-th thermal power generation unit accumulation low-cycle fatigue life loss:

(1) if Δ E _ithe little accumulation low-cycle fatigue life loss showing this thermal power generation unit is large, the little residual life of accumulation low-cycle fatigue life loss margin of safety is short, the optimal control measure recommended is multi-band basic load, participates in peak regulation less, to extend the serviceable life of this thermal power generation unit;

(2) if Δ E _ishow that greatly the accumulation low-cycle fatigue life loss of this thermal power generation unit is little, accumulation low-cycle fatigue life loss margin of safety is large, residual life is long, more the optimal control measure recommended participates in peak regulation, with the residual life of this thermal power generation unit of reasonable employment;

21 step, printout result:

The online result of calculation of accumulation low-cycle fatigue life loss of printout thermal power generation unit vitals and control measure as required, the optimizing operation being applied to thermal power generation unit controls.

3 subcritical 300MW thermal power generation unit have been installed in certain fuel-burning power plant, to septum valve, high pressure rotor, generator guard ring, boiler drum totally 4 vitals, adopt the device shown in Fig. 1, the computer software shown in the method shown in Fig. 2 and Fig. 3, the accumulation low-cycle fatigue life loss result of calculation of 12 vitals of 3 thermal power generation unit of this fuel-burning power plant calculated lists in Fig. 4.

The first step: every Δ τ=1 minute, main steam pressure is read from the scattered control system of 3 thermal power generation unit and online measuring point by plant level supervisory information system, main steam temperature, reheated steam pressure, reheat steam temperature, vapor pressure after governing stage, vapor (steam) temperature after governing stage, one steam pumping pressure, one steam pumping temperature, high row's vapor pressure, high row's vapor (steam) temperature, middle row's vapor pressure, middle row's vapor (steam) temperature, high-pressure inner cylinder metal temperature, IP inner casing metal temperature, five steam pumping pressure, five steam pumping temperature, six steam pumping pressure, six steam pumping temperature, seven steam pumping pressure, eight steam pumping pressure, turbine speed, power, condenser pressure, feed pressure, feed temperature, generator active power, power factor, three-phase current and voltage, exciting current, cold hydrogen temperature and hot hydrogen temperature, the wall temperature measurement point numerical value of boiler drum,

Second step and the 15 step: during from operation to 31 days 24 Dec in 2012, the accumulation low-cycle fatigue life loss E at 4 positions of 4 vitals of 3 300MW thermal power generation unit _nijresult of calculation list in table 1;

[table 1]

16 step and the 18 step: during from operation to 31 days 24 Dec in 2012, the maximal value E of the accumulation low-cycle fatigue life loss of 3 300MW thermal power generation unit _nmaxi, calendar life loss permissible value [E] _i, 0.75 [E] _iwith accumulation low-cycle fatigue life loss margin of safety Δ E _ilist in table 2 in line computation result of calculation;

[table 2]

Sequence number	Vitals title	No. 1 unit	No. 2 units	No. 3 units
					1	The maximal value E of accumulation low-cycle fatigue life loss Nmaxi	0.3395	0.3305	0.4045
2	Calendar life loss permissible value [E] i	0.5933	0.5700	0.5367
					3	0.75[E] i	0.4450	0.4275	0.4025
3	Accumulation low-cycle fatigue life loss margin of safety Δ E i	0.1055	0.0970	-0.0020

19 step: the optimal control of single unit accumulation low-cycle fatigue life loss:

Come by level of factory monitor message device and thermal power generation unit distributed control apparatus controlthese 3 thermal power generation unit accumulation low-cycle fatigue life loss:

(1) due to the Δ E of No. 1 machine _i=0.1055>=0.1, show that the accumulation low-cycle fatigue life loss margin of safety of No. 1 thermal power generation unit vitals is large, the optimal control measure recommended increases main steam temperature rate of change and load changing rate to carry out the startup of unit, shutdown and load change, the regulation main steam temperature rate of change of " products instruction " that increase amplitude provides for thermal power generation unit manufacturing enterprise and the former numerical value of load changing rate 0.1 times, with the residual life of reasonable employment No. 1 thermal power generation unit;

(2) for the Δ E of No. 2 machines _i=0.0970, due to 0< Δ E _i<0.1, show that the accumulation low-cycle fatigue life loss of No. 2 thermal power generation unit vitals is in slave mode, the optimal control measure of recommendation provides the numerical value of the regulation main steam temperature rate of change of " products instruction " and load changing rate to carry out the startup of No. 2 thermal power generation unit, shutdown and load change according to thermal power generation unit manufacturing enterprise;

(3) because the Δ E of No. 3 machines _i=-0.0020≤0, show that the accumulation low-cycle fatigue life loss margin of safety of No. 3 thermal power generation unit is little and accumulation low-cycle fatigue life loss is large, suggestion reduces main steam temperature rate of change and load changing rate and carries out the startup of unit, shutdown and load change, the regulation main steam temperature rate of change of " products instruction " that minimizing amplitude provides for thermal power generation unit manufacturing enterprise and the former numerical value of load changing rate 0.3 times, to extend the serviceable life of No. 3 thermal power generation unit;

20 step is to the 21 step:

Come by the Optimized Operation of level of factory monitor message device and the department of operation value length controlthese 3 thermal power generation unit accumulation low-cycle fatigue life loss: the Δ E of 3 thermal power generation unit of this fuel-burning power plant _isequence is from small to large: No. 3 machine Δ E _i=-0.0020, No. 2 machine Δ E _i=0.0970, No. 1 machine Δ E _i=0.1055; The Δ E of No. 3 machines _ithe minimum accumulation low-cycle fatigue life loss showing this thermal power generation unit is large, accumulation low-cycle fatigue life loss margin of safety is little, residual life is short, the optimal control measure recommended is No. 3 machine multi-band basic loads, participates in peak regulation less, to extend the serviceable life of No. 3 thermal power generation unit; The Δ E of No. 1 machine _ithe maximum accumulation low-cycle fatigue life loss showing this thermal power generation unit is little, accumulation low-cycle fatigue life loss margin of safety is large, residual life is long, the optimal control measure recommended is No. 1 machine many participations peak regulation, with the low-cycle fatigue life of this thermal power generation unit of reasonable employment; Print the Output rusults of the optimal control of this fuel-burning power plant separate unit and multiple stage unit accumulation low-cycle fatigue life loss, the optimizing operation being applied to 3 thermal power generation unit of this fuel-burning power plant controls.

Adopt the in-service monitoring of the accumulation low-cycle fatigue life loss of thermal power generation unit vitals provided by the invention and control device and method, quantitatively can calculate the accumulation low-cycle fatigue life loss of 3 the 300MW thermal power generation unit vitals in this fuel-burning power plant online, control is optimized according to accumulation low-cycle fatigue life loss margin of safety, No. 1 machine many participations peak regulation, No. 3 machine multi-band basic loads, participates in peak regulation less; No. 1 thermal power generation unit increases main steam temperature rate of change and load changing rate and carries out the startup of unit, shutdown and load change; The regulation main steam temperature rate of change of " products instruction " that No. 2 thermal power generation unit provide by thermal power generation unit manufacturing enterprise and the numerical value of load changing rate are to carry out the startup of unit, shutdown and load change; No. 3 thermal power generation unit reduce main steam temperature rate of change and load changing rate and carry out the startup of unit, shutdown and load change; The accumulation low-cycle fatigue life loss of these 3 300MW thermal power generation unit vitals can be made to be in slave mode, to reach and use a set of accumulation low-cycle fatigue life loss control device in-service monitoring and the technique effect controlling this power plant 3 300MW thermal power generation unit multiple vitals accumulation low-cycle fatigue life loss.

Claims (1)

1. the accumulation low-cycle fatigue life loss on-line monitoring method of a thermal power generation unit vitals, it is characterized in that, C language is adopted to write the computer software of the accumulation low-cycle fatigue life loss of thermal power generation unit vitals, operate in accumulation low-cycle fatigue life loss on calculation server, be applied to accumulation low-cycle fatigue life loss in-service monitoring and the control of thermal power generation unit vitals, its concrete steps are:

The first step, the online measuring point data of reading thermal power generation unit:

Database server minute to 5 minutes, reads main steam pressure by plant level supervisory information system from the scattered control system of thermal power generation unit and online measuring point every Δ τ=0.1, main steam temperature, reheated steam pressure, reheat steam temperature, vapor pressure after governing stage, vapor (steam) temperature after governing stage, one steam pumping pressure, one steam pumping temperature, high row's vapor pressure, high row's vapor (steam) temperature, middle row's vapor pressure, middle row's vapor (steam) temperature, high-pressure inner cylinder metal temperature, IP inner casing metal temperature, five steam pumping pressure, five steam pumping temperature, six steam pumping pressure, six steam pumping temperature, seven steam pumping pressure, eight steam pumping pressure, turbine speed, power, condenser pressure, feed pressure, feed temperature, generator active power, power factor, three-phase current and voltage, exciting current, cold hydrogen temperature and hot hydrogen temperature, the wall temperature measurement point numerical value of boiler drum, the wall temperature measurement point numerical value of steam-water separator, the wall temperature measurement point numerical value of high temperature header, the wall temperature measurement point numerical value of low temperature header, the wall temperature measurement point numerical value of main steam line, the wall temperature measurement point numerical value of reheaing steam pipe,

The thermal stress of second step, calculating vitals:

For the data variation of the online measuring point of fiery thermal power generation unit, adopt existing simplified model, at the temperature field of line computation i-th thermal power generation unit jth vitals and tangential thermal stress σ _{θ thij}, radial thermal stress σ _rthijwith Axial Thermal stress σ _zthij;

The mechanical stress of the 3rd step, calculating vitals:

For the data variation of the online measuring point of fiery thermal power generation unit, adopt existing simplified model, at the tangential mechanical stress σ that line computation i-th thermal power generation unit jth vitals causes due to working medium pressure or working speed _{θ mchij}, radial mechanical stress σ _rmchijwith axial mechanical stress σ _zmchij;

The compound stress of the 4th step, calculating vitals:

According to the following formula, at the compound tangential stress σ of line computation i-th thermal power generation unit jth vitals _{θ ij}, compound radial stress σ _rijwith compound axial stress σ _zij:

σ _θij＝σ _θthij+σ _θmchij；

σ _rij＝σ _rthij+σ _rmchij；

σ _zij＝σ _zthij+σ _zmchij；

The equivalent stress of the 5th step, calculating vitals:

The online computing formula of the equivalent stress of i-th thermal power generation unit jth vitals is:

${\mathrm{\&sigma;}}_{eqij}={\&lsqb;\frac{{({\mathrm{\&sigma;}}_{\mathrm{\&theta;}ij}-{\mathrm{\&sigma;}}_{rij})}^2+{({\mathrm{\&sigma;}}_{rij}-{\mathrm{\&sigma;}}_{zij})}^2+{({\mathrm{\&sigma;}}_{zij}-{\mathrm{\&sigma;}}_{\mathrm{\&theta;}ij})}^2}{2}\&rsqb;}^{\frac{1}{2}};$

6th step, determine the maximum stress of three compound stresses:

In three compound stresses of i-th thermal power generation unit jth vitals, determine maximum stress σ _maxonline computing formula be:

σ _max＝max(σ _θij，σ _rij，σ _zij)；

7th step, determine the minimum stress of three compound stresses:

In three compound stresses of i-th thermal power generation unit jth vitals, determine minimum stress σ _minonline computing formula be:

σ _min＝min(σ _θij，σ _rij，σ _zij)；

The real number field equivalent stress of the 8th step, calculating vitals:

The online computing formula of the real number field equivalent stress of i-th thermal power generation unit jth vitals is:

σ _ij＝σ _eqij×sign(σ _max+σ _min)；

In formula, sign (σ _max+ σ _min) be sign function, if (σ _max+ σ _min) > 0, then sign (σ _max+ σ _min)=1; If (σ _max+ σ _min) < 0, then sign (σ _max+ σ _mm)=-1;

9th step, division have the stress period of same sign:

For i-th thermal power generation unit jth vitals real number field equivalent stress σ _ijonline result of calculation, according to real number field equivalent stress σ _ijpositive number and the changing moment of negative, real number field equivalent stress σ _ijthe historical data of online result of calculation, according to the time sequencing of in-service monitoring, divides into σ _ij>=0 period and σ _ij< 0 period;

Tenth step, determine σ _ijthe peak stress of>=0 period:

In a certain period, there is the n of i-th thermal power generation unit jth vitals ₁individual real number field equivalent stress σ _ijall be more than or equal to 0, then the peak stress σ of this period i-th thermal power generation unit jth vitals _ijponline computing formula be:

${\mathrm{\&sigma;}}_{ijp}=\max ({\mathrm{\&sigma;}}_{ij1},{\mathrm{\&sigma;}}_{ij2},...,{\mathrm{\&sigma;}}_{{\mathrm{ijn}}_1});$

11 step, determine σ _ijthe peak stress σ of < 0 period _ijp:

In another period, there is the n of i-th thermal power generation unit jth vitals ₂individual real number field equivalent stress σ _ijall be less than 0, then the peak stress σ of this period i-th thermal power generation unit jth vitals _ijponline computing formula be:

${\mathrm{\&sigma;}}_{ijp}=\max \left(\left|{\mathrm{\&sigma;}}_{ij1}\right|,\left|{\mathrm{\&sigma;}}_{ij2}\right|,...,\left|{\mathrm{\&sigma;}}_{{\mathrm{ijn}}_2}\right|\right);$

12 step, the low-cycle fatigue strain amplitude that calculating vitals peak stress is corresponding:

Adopt following formula, calculate the low-cycle fatigue strain amplitude ε of symmetrical fatigue and cyclic corresponding to an i platform thermal power generation unit jth vitals peak stress _aij:

ε _aij＝(1+μ)σ _ijp/(1.5E)；

In formula, μ is the Poisson ratio of material under i-th thermal power generation unit jth vitals working temperature, and E is the elastic modulus of material under i-th thermal power generation unit jth vitals working temperature;

13 step, the low-cycle fatigue life that calculating vitals peak stress is corresponding:

Adopt prior art, use the low-cycle fatigue curve ε of vitals material _aij=F (N _fij), calculate 1 time every Δ τ, draw the low-cycle fatigue life N of i-th thermal power generation unit jth symmetrical cycle that vitals peak stress is corresponding _fij;

14 step, the transient-state low-cycle fatigue life loss that calculating vitals peak stress is corresponding:

Adopt following formula, at the transient-state low-cycle fatigue life loss d that the peak stress of line computation i-th thermal power generation unit jth vitals is corresponding _ijp:

d _ijp＝(2N _fij) ^-1×100％；

The accumulation low-cycle fatigue life loss of the 15 step, calculating vitals:

The accumulation low-cycle fatigue life loss E of i-th thermal power generation unit jth vitals _nijonline computing formula be expressed as:

E _Nij＝E _Nij0+d _ijp；

In formula, E _nij0be that i-th thermal power generation unit jth vitals adds up the accumulation low-cycle fatigue life loss calculated after transient-state low-cycle fatigue life loss corresponding to previous peak stress;

16 step, determine the maximal value of the accumulation low-cycle fatigue life loss of i-th unit:

In m vitals of i-th thermal power generation unit, the maximal value E of accumulation low-cycle fatigue life loss _nmaxionline computing formula be expressed as:

E _Nmaxi＝max(E _Ni1，E _Ni2，…，E _Nim)；

The calendar life loss permissible value of the 17 step, calculating i-th unit:

The calendar life loss permissible value [E] of i-th thermal power generation unit of being on active service within the design phase in longevity _ionline computing formula be expressed as:

The accumulation low-cycle fatigue life loss margin of safety of the 18 step, calculating i-th unit:

The accumulation low-cycle fatigue life loss margin of safety Δ E of i-th thermal power generation unit _ionline computing formula be expressed as:

ΔE _i＝0.75×[E] _i-E _Nmaxi-0.25；

At accumulation low-cycle fatigue life loss margin of safety Δ E _ion the right side of the equal sign of computing formula 0.75 [E] _i, represent that life consumption leaves the safe clearance of 0.25, in order to the creep life consumption of high-temperature component and other life consumptions of low-temperature components;

The optimal control of the 19 step, i-th unit accumulation low-cycle fatigue life loss:

I-th thermal power generation unit accumulation low-cycle fatigue life loss is controlled by level of factory monitor message device and thermal power generation unit distributed control apparatus:

(1) if 0 < Δ E _i< 0.1, show that the accumulation low-cycle fatigue life loss of i-th thermal power generation unit vitals is in slave mode, the optimal control measure of recommendation provides the regulation main steam temperature rate of change of " products instruction " and the numerical value of load changing rate to carry out the startup of unit, shutdown and load change according to thermal power generation unit manufacturing enterprise;

(2) if Δ E _i>=0.1, show that the accumulation low-cycle fatigue life loss margin of safety of i-th thermal power generation unit vitals is large, the optimal control measure recommended increases main steam temperature rate of change and load changing rate to carry out the startup of unit, shutdown and load change, the regulation main steam temperature rate of change of " products instruction " that increase amplitude provides for thermal power generation unit manufacturing enterprise and the former numerical value of load changing rate 0.1 ~ 0.3 times, with the residual life of this thermal power generation unit of reasonable employment;

(3) if Δ E _i≤ 0, show that the accumulation low-cycle fatigue life loss margin of safety of i-th thermal power generation unit is little and accumulation low-cycle fatigue life loss is large, suggestion reduces main steam temperature rate of change and load changing rate and carries out the startup of unit, shutdown and load change, the regulation main steam temperature rate of change of " products instruction " that minimizing amplitude provides for thermal power generation unit manufacturing enterprise and the former numerical value of load changing rate 0.2 ~ 0.6 times, to extend the serviceable life of this thermal power generation unit;

The optimal control of the 20 step, level of factory multiple stage unit accumulation low-cycle fatigue life loss:

The accumulation low-cycle fatigue life loss margin of safety Δ E of level of factory multiple stage thermal power generation unit _isort from small to large, according to Δ E _ithe size optimizing operation that carries out level of factory multiple stage thermal power generation unit control, the Optimized Operation grown by level of factory monitor message device and operation department value controls i-th thermal power generation unit accumulation low-cycle fatigue life loss:

(1) if Δ E _ithe little accumulation low-cycle fatigue life loss showing this thermal power generation unit is large, accumulation low-cycle fatigue life loss margin of safety is little, residual life is short, the optimal control measure recommended is multi-band basic load, participates in peak regulation less, to extend the serviceable life of this thermal power generation unit;

(2) if Δ E _ishow that greatly the accumulation low-cycle fatigue life loss of this thermal power generation unit is little, accumulation low-cycle fatigue life loss margin of safety is large, residual life is long, more the optimal control measure recommended participates in peak regulation, with the residual life of this thermal power generation unit of reasonable employment;

21 step, printout result:

The online result of calculation of accumulation low-cycle fatigue life loss of printout thermal power generation unit vitals and control measure as required, the optimizing operation being applied to thermal power generation unit controls.