阅读说明：本技术 基于蒸汽过热度参数的管道疏水方法及系统 (Pipeline trapping method and system based on steam superheat parameter ) 是由 袁红蕾 刘新龙 苑晔 姜洪林 张民茹 王伟 于 2019-09-26 设计创作，主要内容包括：本发明提供的基于蒸汽过热度参数的管道疏水方法及系统,根据热蒸汽母管的压力参数确定饱和蒸汽温度,再根据饱和蒸汽温度和疏水罐内部蒸汽的温度参数得到疏水罐内部蒸汽的过热度,最后根据过热度与预设值比较,输出疏水阀的开闭指令,对机组启停初期低负荷工况下过热蒸汽管道可能产生的凝结水以及低过热度蒸汽及时准确疏放回收。有效解决了火力发电厂、太阳能热发电厂现有控制策略,造成的启动周期增长、疏水阀及管道热冲击大、合格蒸汽被疏放的热量损失大的问题。适用于所有过热状态的蒸汽管道在低参数工况进行自动疏水的工艺过程,工业适用面广,节能效果显著。(Pipeline trapping method and system provided by the invention based on steam superheat parameter, saturated-steam temperature is determined according to the pressure parameter of hot steam main pipe, the degree of superheat of drain trap steam inside is obtained further according to the temperature parameter of saturated-steam temperature and drain trap steam inside, finally according to the degree of superheat compared with preset value, the opening and closing instruction for exporting drain valve, to the issuable condensed water of superheat steam pipeline under Unit Commitment initial stage running on the lower load and the promptly and accurately unrestrained recycling of low overheat steam.Efficiently solve thermal power plant, the existing control strategy of solar energy thermal-power-generating factory, caused by the starting period increases, big, the qualified steam of drain valve and pipeline thermal shock is big by unrestrained thermal loss problem.Jet chimney suitable for all superheat states carries out the technical process of automatic hydrophobic in low parameter operating condition, and industry is widely applicable, and energy-saving effect is significant.)

1. the pipeline trapping method based on steam superheat parameter, which is characterized in that include the following steps,

S100 obtains the temperature parameter T of drain trap steam inside on superheat steam pipeline₁And the pressure ginseng of superheated steam main pipe Number P₁；

S200, according to the pressure parameter P of superheated steam main pipe₁, determine the saturated-steam temperature T under corresponding pressure₂；

S300, according to saturated-steam temperature T₂With the temperature parameter T of drain trap steam inside₁, determine the mistake of drain trap steam inside Temperature Ts；

Step S300 is obtained the degree of superheat Ts of drain trap steam inside by S400, with the high setting value TsH of preset steam superheat Setting value TsL low with steam superheat is compared, and the switch of drain valve is controlled according to comparison result；

As Ts≤TsL, then drain valve is opened；

It as Ts >=TsH, is then delayed after setting time, closes drain valve.

2. according to claim 1 based on the pipeline trapping method of steam superheat parameter, which is characterized in that in step S100 It obtains superheated steam main pipe pressure parameter at the three of steam turbine side simultaneously, and pressure parameter at three is done into average value processing, obtain The pressure parameter P of superheated steam main pipe₁。

3. according to claim 1 based on the pipeline trapping method of steam superheat parameter, which is characterized in that in step S300 The specific method of determination of the degree of superheat Ts of drain trap steam inside is as follows；

Degree of superheat Ts=temperature parameter T₁Saturated-steam temperature T₂

4. according to claim 1 based on the pipeline trapping method of steam superheat parameter, which is characterized in that step S400 In:

The high setting value TsH of steam superheat is than steam superheat parameter T₂It is 35~45 DEG C high；

The low setting value TsL of steam superheat is higher than steam superheat, and setting value TsH is 10~15 DEG C low.

5. a kind of system of the pipeline trapping method described in any one of claim 1-4 based on steam superheat parameter, feature It is, including control unit and temperature sensor connected to it and pressure transmitter, pressure transmitter installs steam main pipe On road, temperature sensor is mounted on drain trap；

Control unit includes saturated-steam temperature module, subtraction block, high level comparison module and low value comparison module；

Temperature sensor and the input terminal of subtraction block connect；

Pressure transmitter is connect with the input terminal of saturated-steam temperature module, the output end and subtraction mould of saturated-steam temperature module The input terminal of block connects；

The output end of subtraction block is connect with high level comparison module and low value comparison module respectively.

6. the system of the pipeline trapping method based on steam superheat parameter according to claim 5, which is characterized in that described The output end of high level comparison module is also connected with time delay module.

7. the system of the pipeline trapping method based on steam superheat parameter according to claim 5, which is characterized in that described Temperature sensor is connected by filter and the input terminal of subtraction block.

8. the system of the pipeline trapping method based on steam superheat parameter according to claim 5, which is characterized in that described Temperature detection mounting hole is provided on drain trap, temperature detection mounting hole is located at top-down 3/5 height and position of drain trap, Temperature sensor is mounted on the temperature detection mounting hole of drain trap.

9. the system of the pipeline trapping method based on steam superheat parameter according to claim 5, which is characterized in that described The quantity of pressure transmitter is the setting of multiple redundancies, and multiple pressure transmitters are equidistantly arranged close to the steam main pipe of steam turbine side On road.

10. the system of the pipeline trapping method based on steam superheat parameter according to claim 9, which is characterized in that institute It states multiple pressure transmitters and passes through filter respectively and connect with mean module, the input of mean module and saturated-steam temperature module End connection.

Technical field

The invention belongs to Thermal Power Station's thermal control system technical fields, the specially pipe based on steam superheat parameter Road trapping method and system.

Background technique

During the underload open in power plant, shut down, therrmodynamic system will appear the low operating condition of steam superheat.If steamed The degree of superheat of vapour is insufficient, into steam turbine superheated steam after former grade blades temperature reduce larger, grade blade after arrival Temperature be possible to that down to saturation temperature moist steam can be changed into.Moist steam with water to the very harmful of blade, so into vapour The degree of superheat of the steam of wheel unit will control safer at 50~100 DEG C.Steam turbine plant can be to initial steam pressure, temperature finite value It is required that seeking to guarantee the degree of superheat into vapour, turbine water induction is prevented, protects equipment safety.

Conventional thermal power plant superheat steam pipeline setting Pneumatic steam trap valve, be according in shutdown process unit load it is big Small direct interlocking opens/closes, and is not provided with any detection instrument.Its specific practice is: in load less than 20% operating condition, interlocking Open all pipeline drain valves；Load is greater than 20%, all pipeline drain valves of interlocking close after certain time-delay；Although its machine Continuity, the stability of group operation are good, and unit opens, stops that number is less, but the extensive control program that this drain valve is imposed uniformity without examining individual cases, The start and stop rapidity and the economy during start and stop that still will affect unit.

In solar energy thermal-power-generating project, there are many operating conditions for being different from thermal power plant, especially in night electricity consumption Low-valley interval, some photo-thermal power generation factories have shutdown mode；After sunrise, start to start Turbo-generator Set equipment.Frequency in this way Numerous ground start and stop unit, in starting, pre-warm stage, it may appear that cross the biggish operating conditions of vapour sources parameter fluctuation such as hot vapour, reheating vapour hot arc. The design of pipeline automatic hydrophobic is to ensure that this technical process should be steady as far as possible, quick, to prevent turbine water induction, contracts The short starting period guarantees unit safety operation.

The start and stop of solar energy thermal-power-generating project unit are frequent, such as still hydrophobic using traditional control strategy progress pipeline: The open and close simultaneously of all drain valves, will cause that the starting period is long, drain valve thermal shock is big, the qualified working medium in part is by lowered temperature reclamation.It makes At every loss and biggish thermal loss.

Summary of the invention

For unit frequent start-stop in the prior art, every loss and the larger problem of thermal loss, the present invention is caused to mention For a kind of pipeline trapping method and system based on steam superheat parameter, according to the vapor (steam) temperature of superheat steam pipeline drain trap Parameter controls the opening and closing of drain valve, effectively shortens and starts the period, reduces working medium thermal loss, improves unit economy.

The present invention is to be achieved through the following technical solutions:

Pipeline trapping method based on steam superheat parameter, includes the following steps,

S100 obtains the temperature parameter T of drain trap steam inside on superheat steam pipeline₁And superheated steam main pipe Pressure parameter P₁；

S200, according to the pressure parameter P of superheated steam main pipe₁, determine the saturated-steam temperature T under corresponding pressure₂；

S300, according to saturated-steam temperature T₂With the temperature parameter T of drain trap steam inside₁, determine drain trap steam inside Degree of superheat Ts；

Step S300 is obtained the degree of superheat Ts of drain trap steam inside by S400, is set with preset steam superheat height Value TsH and the low setting value TsL of steam superheat are compared, and the switch of drain valve is controlled according to comparison result；

As Ts≤TsL, then drain valve is opened；

It as Ts >=TsH, is then delayed after setting time, closes drain valve.

Preferably, superheated steam main pipe pressure parameter at the three of steam turbine side is obtained simultaneously in step S100, and by three Place's pressure parameter does average value processing, obtains the pressure parameter P of superheated steam main pipe₁。

Preferably, the specific method of determination of the degree of superheat Ts of drain trap steam inside is as follows in step S300；

Degree of superheat Ts=temperature parameter T₁Saturated-steam temperature T₂

Preferably, in step S400:

The high setting value TsH of steam superheat is than steam superheat parameter T₂It is 35~45 DEG C high；

The low setting value TsL of steam superheat is higher than steam superheat, and setting value TsH is 10~15 DEG C low.

The present invention also provides a kind of system of the pipeline trapping method of above-mentioned steam superheat parameter, including control unit, And temperature sensor connected to it and pressure transmitter, pressure transmitter are installed on steam main pipe road, temperature sensor peace On drain trap；

Control unit includes that mean module, saturated-steam temperature module, subtraction block, high level comparison module, low value compare Module and extension of module；

Temperature sensor and the input terminal of subtraction block connect；

Pressure sensor is connect with the input terminal of saturated-steam temperature module, the output end of saturated-steam temperature module with subtract The input terminal of method module connects；

The output end of subtraction block is connect with high level comparison module and low value comparison module respectively.

Preferably, the output end of the high level comparison module is also connected with time delay module.

Preferably, the temperature sensor is connected by filter and the input terminal of subtraction block.

Preferably, it is provided with temperature detection mounting hole on the drain trap, temperature detection mounting hole is located at drain trap from upper At 3/5 height and position under and, temperature sensor is mounted on the temperature detection mounting hole of drain trap.

Preferably, the quantity of the pressure transmitter is the setting of multiple redundancies, and multiple pressure transmitters are equidistantly mounted on On the steam main pipe road of steam turbine side.

Preferably, the multiple pressure transmitter passes through filter respectively and connect with mean module, mean module and saturation The input terminal of vapor (steam) temperature module connects.

Compared with prior art, the invention has the following beneficial technical effects:

Pipeline trapping method disclosed by the invention based on steam superheat parameter, according to the pressure parameter of hot steam main pipe It determines saturated-steam temperature, is obtaining steaming inside drain trap according to the temperature parameter of saturated-steam temperature and drain trap steam inside The degree of superheat of vapour controls the opening and closing of drain valve finally according to the degree of superheat compared with preset value, and steam superheat high level and steaming is arranged Vapour degree of superheat low value, avoids the degree of superheat from stirring near preset value, causes the opening and closing repeatedly of drain valve.This method can be to start and stop The issuable condensed water of superheat steam pipeline and low overheat steam promptly and accurately unrestrained time under machine initial stage running on the lower load Control is received, it is low according to unit to efficiently solve thermal power plant, a large amount of superheat steam pipeline drain valves of solar energy thermal-power-generating factory Opened simultaneously when load, the control strategy that unit simultaneously closes off after certain load, caused by starting the period increase, drain valve and The problem of big, the qualified steam of pipeline thermal shock is by unrestrained thermal loss.It can effectively shorten the unit starting time, reduce system Thermal shock and system parameter fluctuation, thermal loss caused by avoiding qualified working medium from recycling, improve system and unit equipment operation is steady It is qualitative, effectively extend the service life of equipment by being precisely controlled.Jet chimney suitable for all superheat states is in low parameter Operating condition carries out the technical process of automatic hydrophobic, and industry is widely applicable, and energy-saving effect is significant.

It obtains the pressure parameter of redundancy setting in hot steam main pipe and carries out average value processing, mention high control precision.

Pipeline draining system provided by the invention based on steam superheat parameter, passes through temperature sensor and pressure inverting Device temperature collection and pressure parameter, are then input to logic module, obtain degree of superheat Ts by subtraction block, finally by comparing Module is compared, and exports the switch order of drain valve, and implementation is simple, low in cost.

Detailed description of the invention

Fig. 1 is that the present invention is based on the structure charts of the pipeline draining system of steam superheat parameter；

Fig. 2 is the structure chart of drain trap of the present invention；

Fig. 3 is the control logic configuration figure of trapping method of the present invention.

Specific embodiment

Present invention will be described in further detail below with reference to the accompanying drawings, described to be explanation of the invention rather than limit It is fixed.

Refering to Fig. 3, the pipeline trapping method based on steam superheat parameter includes the following steps,

S100 obtains superheat steam pipeline drain trap inside temperature parameter T₁And superheated steam main-piping pressure parameter P₁；

S200, according to superheated steam main-piping pressure parameter P₁, the saturated-steam temperature T under corresponding pressure is calculated₂；

Then according to saturated-steam temperature T₂With drain trap inside temperature parameter T₁, drain trap steam inside is calculated Degree of superheat Ts, unit are DEG C；

S300, using the degree of superheat Ts of drain trap steam inside, with preset steam superheat high level TsH and steam superheating Degree low value TsL is compared, and the switch of drain valve is controlled according to comparison result.

As Ts≤TsL, then drain valve is opened；

It as Ts >=TsH, is then delayed after t seconds, closes drain valve.

Refering to fig. 1 with 2, a kind of pipeline draining system based on steam superheat parameter, including control unit, and and its The temperature sensor of connection and multiple pressure transmitters.

The multiple pressure transmitter is equidistantly arranged close on the steam main pipe road of steam turbine side, overheated steam pipe it is low It is provided with drain trap on the straight section pipeline of position, temperature detection mounting hole is provided on drain trap, temperature detection mounting hole is located at hydrophobic At the height and position of tank top-down 3/5, temperature sensor is mounted on the temperature detection mounting hole of drain trap.

Control unit includes that multiple filters, mean module, saturated-steam temperature module, subtraction block, high level compare mould Block, low value comparison module and extension of module.

Temperature sensor is connected by the input terminal of first filter and subtraction block；

Multiple pressure sensors pass through a filter respectively and connect with mean module, mean module and saturated-steam temperature The input terminal of module connects, and the output end of saturated-steam temperature module and the input terminal of subtraction block connect.

The output end of subtraction block is connect with high level comparison module and low value comparison module respectively, high level comparison module it is defeated Outlet is also connected with time delay module.

The temperature parameter T of the drain trap of temperature sensor acquisition₁, subtraction is input to after being filtered by first filter Module.

The quantity of pressure sensor is three, the pressure parameter for the superheated steam main pipe that three pressure sensors respectively acquire, It is separately input into filter connected to it to be filtered, filtered three pressure parameters are separately input into mean module, obtain To pressure mean value, pressure mean value is input to saturated-steam temperature module again, and saturated-steam temperature module exports saturated-steam temperature T₂。

In subtraction block, temperature parameter T₁Subtract saturated-steam temperature T₂Obtain the degree of superheat Ts of drain trap steam inside.

Degree of superheat Ts is separately input into high level comparison module and low value comparison module, presets steam mistake in high level comparison module Temperature high setting value TsH presets the low setting value TsL of steam superheat in low value comparison module.

Steam superheat Ts is through low value comparison module operation, and as Ts≤TsL, low value comparison module output drain valve opens finger It enables.

Steam superheat Ts is through high level judgment module operation, and as Ts >=TsH, high level judges that the output valve of mould is passed through along delay After module DELAY is delayed t seconds, output drain valve closes instruction.

The high setting value TsH of steam superheat is than steam superheat parameter T₂It is 35~45 DEG C high；

The low setting value TsL of steam superheat is higher than steam superheat, and setting value TsH is 10~15 DEG C low.Specific setting value is by work Process system safety and technical process concrete condition determine.

Saturated-steam temperature module can choose the PTCAL module of Shanghai Xinhua company, Guo electricity Zhi Shen company ENTHAPLY module or the STEAMTABLE module of Ai Mosheng company.

Described control unit is DCS/PLC control unit.

Filter can choose the FILTER module of Shanghai Xinhua company, the LEADLAG module of Guo electricity Zhi Shen company or Chinese mugwort The SMOOTH module of Mo Sheng company.

The calculating process of steam superheat are as follows: steam superheat Ts=vapor (steam) temperature T₁Saturated-steam temperature T₂, steam mistake The standard unit of temperature is degree Celsius (DEG C).The high setting value TsH of steam superheat and the low setting value TsL foundation of steam superheat Operating experience proposes initial value, combines field adjustable process to correct to obtain final definite value when field conduct；Time delay module DELAY's Delay time t can be provided in debugging process according to on-site actual situations.

Pipeline draining system provided by the invention based on steam superheat parameter, can be to each drain valve according to hydrophobic The steam parameter of point is individually controlled, and control precision is improved, and can be realized in steam superheat deficiency unrestrained time in time Condensed water is received, turbine water induction is prevented；Secondly, can unrestrained recycling low overheat steam working medium, realize starting, heating coil technique Process；Drain valve can be closed in time after hydrophobic point steam quality is up to standard again, enter next technical process as early as possible, shorten unit Start the time；In addition, controlling drain valve respectively, system thermal shock is reduced, reduces system parameter fluctuation, qualified working medium is avoided to recycle Caused by heat loss, improve system and unit equipment operation stability and service life, be to improve controlled level, realize technique mistake The effective ways of journey precise controlling.

Pipeline trapping method provided by the invention based on steam superheat parameter, in the superheated steam of any therrmodynamic system Pipeline can be used there are the technical process that running on the lower load needs automatic hydrophobic.In conventional thermal power plant project application, Traditional control strategy is substituted, control precision can also be significantly improved, reduce certain thermal losses.In solar energy thermal-power-generating project, Energy-saving effect becomes apparent from.Be applicable to following technical process in power plant therrmodynamic system: main steam line is hydrophobic, reheated steam Hot arc pipeline is hydrophobic, each section of extraction line of high pressure cylinder is hydrophobic etc..

The above content is merely illustrative of the invention's technical idea, and this does not limit the scope of protection of the present invention, all to press According to technical idea proposed by the present invention, any changes made on the basis of the technical scheme each falls within claims of the present invention Protection scope within.