阅读说明：本技术 一种母管蒸汽压力协调控制方法及系统 (Method and system for coordinately controlling steam pressure of main pipe ) 是由 柴庆宣 商孟尧 于 2021-07-07 设计创作，主要内容包括：一种母管蒸汽压力协调控制方法及系统,本发明涉及一种采用母管制运行方式的锅炉母管压力协调控制方法及系统,它为解决各锅炉之间如何合理分配负载的问题,所述方法包括步骤一、获取数据；步骤二、计算调压锅炉的数量；步骤三、判断外扰状态；步骤四、计算总蒸汽流量调整量；步骤五、计算分配系数；步骤六、输出数据；所述系统包括母管协调控制器,母管协调控制器包括信息输入模块、调压锅炉统计模块、外扰判断模块、总蒸汽流量调整量计算模块、分配系数计算模块和信息输出模块；本发明用于合理的分配各锅炉之间的负载。(The invention relates to a method and a system for coordinately controlling steam pressure of a main pipe, in particular to a method and a system for coordinately controlling the pressure of the main pipe of a boiler by adopting a main pipe operation mode, which aim to solve the problem of how to reasonably distribute load among boilers and comprise the steps of firstly, acquiring data; step two, calculating the number of the pressure regulating boilers; step three, judging an external disturbance state; step four, calculating the total steam flow adjustment amount; step five, calculating distribution coefficients; step six, outputting data; the system comprises a main pipe coordination controller, wherein the main pipe coordination controller comprises an information input module, a pressure regulating boiler counting module, an external disturbance judging module, a total steam flow regulation calculation module, a distribution coefficient calculation module and an information output module; the invention is used for reasonably distributing the load among the boilers.)

1. A method for coordinately controlling steam pressure of a main pipe is characterized by comprising the following steps: the method comprises the following steps:

step one, acquiring data;

acquiring a steam pressure set value of a steam main pipe (3), a steam pressure measured value of the steam main pipe (3), a steam flow measured value of each boiler combustion system (2), a control mode of each boiler combustion system (2) and a coal feeding amount measured value of each boiler combustion system (2);

step two, calculating the number of the pressure regulating boilers;

counting the number of the boiler combustion systems (2) meeting the condition 1 according to the measured steam flow value of each boiler combustion system (2) and the control mode of each boiler combustion system (2), wherein the condition 1 is as follows: the control mode of the boiler combustion system (2) is a coordinated pressure regulating mode, the steam flow is between the lower operation limit and the upper operation limit, the boiler combustion system (2) meeting the condition 1 is used as a pressure regulating boiler, when the number of the pressure regulating boilers is less than two, coordination control is not needed, the boiler combustion system (2) normally operates, when the number of the pressure regulating boilers is more than two, coordination control is needed, and the step III is shifted;

step three, judging an external disturbance state;

calculating whether the steam pressure of the steam main pipe (3) is in an external disturbance state or not by using an external disturbance judgment algorithm according to the steam pressure measured value of the steam main pipe (3) and the steam flow measured value of each boiler combustion system (2) obtained in the step one, judging that the steam pressure is in the external disturbance state when the steam flow is opposite to the steam pressure change direction, automatically adjusting all the boiler combustion systems (2) to be in a feedforward compensation mode at the moment, obtaining the external disturbance feedforward state value of each boiler combustion system (2), turning to a step four, judging that the steam flow is in a non-external disturbance state when the steam flow is the same as the steam pressure change direction, normally operating all the boiler combustion systems (2), and turning to the step four;

step four, calculating the total steam flow adjustment amount;

calculating the total steam flow adjustment quantity of the steam main pipe (3) by utilizing an incremental PID algorithm and the steam pressure error of the steam main pipe (3) according to the steam pressure set value of the steam main pipe (3) and the steam pressure measured value of the steam main pipe (3) obtained in the step one, and turning to a step five;

step five, calculating distribution coefficients;

according to the measured steam flow value of each boiler combustion system (2), the measured coal supply value of each boiler combustion system (2) and the total steam flow adjustment value obtained in the first step and the fourth step, a non-normalized distribution coefficient vector B and a normalized distribution coefficient A are calculated by using a normalization algorithm, when | | B | | | ≠ 0 represents that the steam pressure coordination requirement is met at the current moment, when | | | B | | | | 0 represents that the steam pressure coordination requirement cannot be met at the current moment, each boiler combustion system (2) is set to be in a non-coordinated mode and manually regulated by a boiler, and the steam flow set value of each boiler combustion system (2) and the control mode set value of each boiler combustion system (2) are obtained;

step six, outputting data;

and sending the external disturbance feedforward state value of each boiler combustion system (2) obtained in the third step, the steam flow set value of each boiler combustion system (2) obtained in the fifth step and the control mode set value of each boiler combustion system (2) to each boiler combustion system (2).

2. The method for coordinately controlling steam pressure in a main pipe according to claim 1, wherein: the steam pressure set value of the steam main pipe (3) in the step one is P_sp1；

The measured value of the steam pressure of the steam main pipe (3) is P_y1；

The measured value of the steam flow of the boiler combustion system (2) is D_y0， The measured value of the steam flow to each boiler combustion system (2) is shown, and T is a matrix transpose;

the control mode of the boiler combustion system (2) is M_y0， Indicating a control mode specific to each boiler combustion system (2);

the measured value of the coal feeding amount of the boiler combustion system (2) is C_y0， Indicating an actual value of the amount of coal fed to each boiler combustion system (2);

the external disturbance feedforward state value of the boiler combustion system (2) is UFb_Dis， Representing an external disturbance feedforward state value specific to each boiler combustion system (2);

the steam flow given value of the boiler combustion system (2) is UD_sp0， Representing a steam flow setpoint specific to each boiler combustion system (2);

the given value of the control mode of the boiler combustion system (2) is UM_sp0， Indicating a control mode setpoint specific to each boiler combustion system (2).

3. The method for coordinately controlling steam pressure in a main pipe according to claim 2, wherein: in the third step, the method for judging the external disturbance state comprises the following steps:

k is the current time;

epsilon is a steam pressure external disturbance judgment threshold value;

d is the total steam flow of the combustion systems (2) of the plurality of boilers, and the calculation formula is as follows:

the external disturbance state comprises a positive external disturbance state and a negative external disturbance state;

UFb_Dis1, being in a positive external disturbance state;

UFb_Dis1, which is in a negative external disturbance state;

UFb_Disand (0) in a state without external disturbance.

4. The method for coordinately controlling steam pressure in a main pipe according to claim 2, wherein: in the fourth step, the method for calculating the total steam flow adjustment amount through the incremental PID algorithm and the steam pressure error of the steam main pipe (3) comprises the following steps:

δU_D(k)＝K_p(e(k)-e(k-1))+K_i(e(k))+K_d(e(k)-2e(k-1)+e(k-2)) (3)

wherein, δ U_D(k) Representing the total steam flow adjustment at time k;

K_Pis a proportional control coefficient;

K_iis an integral control coefficient;

K_dis a differential control coefficient;

e (k) represents the steam pressure control error of the steam main pipe (3) at the time k,

e(k)＝P_sp1(k)-P_y1(k) (4)

P_sp1(k) the steam pressure set value of the steam main pipe (3) at the moment k is represented;

P_y1(k) the measured value of the steam pressure of the steam main pipe (3) at the time k is shown.

5. The method for coordinately controlling steam pressure in a main pipe according to claim 2, wherein: the fifth step comprises the following steps:

steam flow of boiler combustion system (2)Given value UD_sp0(k)：

UD_sp0(k)＝ΔUD_sp0(k)+UD_sp0(k-1) (5)

Wherein UD_sp0(k-1) is the steam flow given value of the boiler combustion system (2) at the last moment;

ΔUD_sp0(k) the variable quantity is the given value of the steam flow of the boiler combustion system (2) at the previous moment and the current moment;

ΔUD_sp0(k)＝[α₁,α₂,…,α_N]^T*δU_D(k) (6)

distribution coefficient alpha_iI is 1,2, …, N, and satisfies:

n is the number of the boiler combustion systems (2);

and calculating distribution coefficients by integrating the running states of the boiler combustion systems (2), wherein the vector of the distribution coefficient of the steam flow adjustment amount of each boiler combustion system (2) is recorded as:

A＝[α₁,α₂,…,α_N]^T

non-normalized distribution coefficient vector:

B＝[β₁,β₂,…,β_N]^T

and (3) normalization calculation:

non-normalized coefficient:

wherein i is 1,2, …, N;

weighting coefficients for coal consumption characteristics;

weighting coefficients for the steam flow margin;

weighting coefficients for the control modes;

wherein T is a calculation statistical period;

j is the control calculation time;

wherein the content of the first and second substances,the steam flow operation upper limit value of the boiler combustion system I (2);

the steam flow operation lower limit value of the boiler combustion system I (2);

wherein the content of the first and second substances,indicating the corresponding potThe furnace combustion system (2) is in a coordination mode;

indicating that the respective boiler combustion system (2) is in non-coordinated mode;

and (3) outputting a control mode:

wherein, | B | | ≠ 0 indicates that the steam pressure coordination requirement is satisfied at the current moment;

and if the condition is that the steam pressure coordination requirement cannot be met at the current moment, setting each boiler combustion system (2) into a non-coordination mode, and manually adjusting by a furnace.

6. The utility model provides a female pipe steam pressure coordinated control system, it includes female pipe coordinated control ware (1), and female pipe coordinated control ware (1) output control signal sends for a plurality of boiler combustion system (2), and every boiler combustion system (2) output corresponding steam flow to female pipe of steam (3), its characterized in that:

the main pipe coordination controller (1) comprises an information input module, a pressure regulating boiler statistics module, an external disturbance judgment module, a total steam flow regulation calculation module, a distribution coefficient calculation module and an information output module;

an information input module which is simultaneously connected with each boiler combustion system (2) and the steam main pipe (3), used for obtaining a steam pressure set value of the steam main pipe (3), a steam pressure measured value of the steam main pipe (3), a steam flow measured value of each boiler combustion system (2), a control mode of each boiler combustion system (2) and a coal feeding amount measured value of each boiler combustion system (2), and the measured value of the steam pressure of the steam main pipe (3) and the measured value of the steam flow of each boiler combustion system (2) are sent to an external disturbance judgment module, meanwhile, sending a steam pressure set value of the steam main pipe (3) and a steam pressure measured value of the steam main pipe (3) to a total steam flow adjustment quantity calculation module, and sending a steam flow measured value of each boiler combustion system (2) and a coal feeding quantity measured value of each boiler combustion system (2) to a distribution coefficient calculation module;

the pressure-regulating boiler counting module is connected with the information input module and used for receiving the steam flow measured value of each boiler combustion system (2) sent by the information input module and the control mode of each boiler combustion system (2), counting the number of the boiler combustion systems (2) meeting the condition 1 according to the received data, wherein the condition 1 is as follows: the control mode of the boiler combustion system (2) is a coordinated pressure regulating mode, and the steam flow is between the lower limit of operation and the upper limit of operation; taking the boiler combustion system (2) meeting the condition 1 as a pressure regulating boiler, judging whether coordination is needed according to the number of the pressure regulating boilers, if coordination control is needed, sending a coordination instruction to an external disturbance judgment module and a total steam flow regulation calculation module, and if coordination control is not needed, normally operating the boiler combustion system (2);

the external disturbance judgment module is simultaneously connected with the information input module, the pressure regulating boiler statistics module and the information output module, and is used for receiving a steam pressure actual measurement value of the steam main pipe (3) and a steam flow actual measurement value of each boiler combustion system (2) sent by the information input module and a coordination instruction sent by the pressure regulating boiler statistics module, calculating whether the steam pressure of the steam main pipe (3) is in an external disturbance state or not by using an external disturbance judgment algorithm according to the received data, and sending an external disturbance feedforward state value of each boiler combustion system (2) to the information output module;

the total steam flow adjustment quantity calculation module is simultaneously connected with the information input module, the pressure regulating boiler statistics module and the distribution coefficient calculation module, and is used for receiving a steam pressure set value of the steam main pipe (3) and a steam pressure measured value of the steam main pipe (3) sent by the information input module and a coordination instruction sent by the pressure regulating boiler statistics module, calculating the total steam flow adjustment quantity of the steam main pipe (3) according to the received data by utilizing an incremental PID algorithm and a steam pressure error of the steam main pipe (3), and sending the total steam flow adjustment quantity to the distribution coefficient calculation module;

the distribution coefficient calculation module is simultaneously connected with the information input module, the total steam flow adjustment quantity calculation module and the information output module, and is used for receiving the steam flow measured value of each boiler combustion system (2) and the coal feeding quantity measured value of each boiler combustion system (2) sent by the information input module and the total steam flow adjustment quantity sent by the total steam flow adjustment quantity calculation module, calculating a non-normalized distribution coefficient vector B and a normalized distribution coefficient A by using a normalization algorithm, and sending a steam flow given value of each boiler combustion system (2) and a control mode given value of each boiler combustion system (2) to the information output module;

and the information output module is simultaneously connected with the external disturbance judgment module, the distribution coefficient calculation module and each boiler combustion system (2) and is used for receiving the external disturbance feedforward state value of each boiler combustion system (2) sent by the external disturbance judgment module, the steam flow given value of each boiler combustion system (2) and the control mode given value of each boiler combustion system (2) sent by the distribution coefficient calculation module and sending the received data to each boiler combustion system (2).

7. The system for coordinately controlling steam pressure in a main pipe according to claim 6, wherein:

the steam pressure set value of the steam main pipe (3) is P_sp1；

The measured value of the steam pressure of the steam main pipe (3) is P_y1；

The measured value of the steam flow of the boiler combustion system (2) is D_y0， The measured value of the steam flow to each boiler combustion system (2) is shown, and T is a matrix transpose;

the control mode of the boiler combustion system (2) is M_y0， Indicating a control mode specific to each boiler combustion system (2);

the measured value of the coal feeding amount of the boiler combustion system (2) is C_y0， Indicating an actual value of the amount of coal fed to each boiler combustion system (2);

the external disturbance feedforward state value of the boiler combustion system (2) is UFb_Dis， Representing an external disturbance feedforward state value specific to each boiler combustion system (2);

the steam flow given value of the boiler combustion system (2) is UD_sp0， Representing a steam flow setpoint specific to each boiler combustion system (2);

the given value of the control mode of the boiler combustion system (2) is UM_sp0， Indicating a control mode setpoint specific to each boiler combustion system (2).

8. The system for coordinately controlling steam pressure in a main pipe according to claim 7, wherein: the method for judging the external disturbance state by the external disturbance judgment module comprises the following steps:

k is the current time;

epsilon is a steam pressure external disturbance judgment threshold value;

d is the total steam flow of the combustion systems (2) of the plurality of boilers, and the calculation formula is as follows:

the external disturbance state comprises a positive external disturbance state and a negative external disturbance state;

UFb_Dis1, being in a positive external disturbance state;

UFb_Dis1, which is in a negative external disturbance state;

UFb_Disand (0) in a state without external disturbance.

9. The system for coordinately controlling steam pressure in a main pipe according to claim 7, wherein: the method for calculating the total steam flow adjustment amount through the incremental PID algorithm in the total steam flow adjustment amount calculation module and the steam pressure error of the steam main pipe (3) comprises the following steps:

δU_D(k)＝K_p(e(k)-e(k-1))+K_i(e(k))+K_d(e(k)-2e(k-1)+e(k-2)) (14)

wherein, δ U_D(k) Representing the total steam flow adjustment at time k;

K_pis a proportional control coefficient;

K_iis an integral control coefficient;

K_dis a differential control coefficient;

e (k) represents the steam pressure control error of the steam main pipe (3) at the time k,

e(k)＝P_sp1(k)-P_y1(k) (15)

P_sp1(k) the steam pressure set value of the steam main pipe (3) at the moment k is represented;

P_y1(k) the measured value of the steam pressure of the steam main pipe (3) at the time k is shown.

10. The system for coordinately controlling steam pressure in a main pipe according to claim 9, wherein: the distribution coefficient calculation module includes:

steam flow given value UD of boiler combustion system (2)_sp0(k)：

UD_sp0(k)＝ΔUD_sp0(k)+UD_sp0(k-1) (16)

Wherein UD_sp0(k-1) is the steam flow given value of the boiler combustion system (2) at the last moment;

ΔUD_sp0(k) change of steam flow given value of boiler combustion system (2) at last moment and current momentAn amount;

ΔUD_sp0(k)＝[α₁,α₂,…,α_N]^T*δU_D(k) (17)

distribution coefficient alpha_iI is 1,2, …, N, and satisfies:

n is the number of the boiler combustion systems (2);

and calculating distribution coefficients by integrating the running states of the boiler combustion systems (2), wherein the vector of the distribution coefficient of the steam flow adjustment amount of each boiler combustion system (2) is recorded as:

A＝[α₁,α₂,…,α_N]^T

non-normalized distribution coefficient vector:

B＝[β₁,β₂,…,β_N]^T

and (3) normalization calculation:

non-normalized coefficient:

wherein i is 1,2, … N;

weighting coefficients for coal consumption characteristics;

weighting coefficients for the steam flow margin;

weighting coefficients for the control modes;

wherein T is a calculation statistical period;

j is the control calculation time;

wherein D is_RHiThe steam flow operation upper limit value of the boiler combustion system I (2);

the steam flow operation lower limit value of the boiler combustion system I (2);

wherein the content of the first and second substances,indicating that the respective boiler combustion system (2) is in a coordinated mode;

indicating that the respective boiler combustion system (2) is in non-coordinated mode;

and (3) outputting a control mode:

wherein, | | B | | ═ 0 represents that the current moment meets the coordination requirement of the steam pressure;

and | B | ≠ 0 represents that the steam pressure coordination requirement cannot be met at the current moment.

Technical Field

The invention relates to a boiler main pipe pressure coordination control method and system adopting a main pipe operation mode.

Background

The main pipe operation mode refers to that a plurality of boilers operate in parallel, steam generated by the boilers enters a main steam main pipe, and steam inlet of a steam turbine and other external heat supply loads all come from the main steam main pipe. When one of the boilers fails, the boiler can be directly cut off, the operation of other boilers is not affected, and the safety and the stability of the unit are improved. In the self-contained thermal power plant and the centralized heat supply industries of the petroleum, chemical, metallurgy, pharmacy and other industries, a parallel operation mode of a plurality of boilers is widely adopted.

The operation of the main pipe unit is a complex thermal process, and in order to ensure the safe and stable operation of the unit, a large number of parameters such as steam temperature, feed water flow, main pipe steam pressure and the like need to be controlled, wherein the control of the main pipe steam pressure is most important. The safe and stable operation of the unit can be influenced by overhigh, overlow or fast change of the steam pressure of the main pipe. The steam pressure of the main pipe is too high, so that explosion accidents easily occur, and serious harm is brought to equipment and personal safety. Too low steam pressure in the main pipe increases steam consumption and coal consumption, the economy of power generation and heat supply is directly influenced, and too fast steam pressure change in the main pipe deteriorates boiler water circulation.

Steam pressure coupling among a plurality of boilers on the main pipe is serious, and particularly the coupling influence is more obvious when only two boilers carry out pressure coordination; when external load disturbance occurs, such as rapid load shedding of a steam turbine due to faults and the like or accident parking of an external network heat utilization device, the pressure parameter of a main steam pipe is greatly fluctuated, so that the economic operation performance of an on-network generator set is reduced, and the safe operation of the set is influenced; the existing boilers all adopt the method of fixing the pressure regulating boilers, the dynamic change of the number of the pressure regulating boilers is not considered, and the long-term stable operation cannot be realized, so that the problem of how to reasonably distribute the load becomes troublesome.

Disclosure of Invention

The invention provides a method and a system for coordinating and controlling steam pressure of a main pipe, which aim to solve the problem of how to reasonably distribute load among boilers.

The technical scheme of the invention is as follows:

a method for coordinately controlling steam pressure of a main pipe comprises the following steps:

step one, acquiring data;

acquiring a steam pressure set value of a steam main pipe, a steam pressure measured value of the steam main pipe, a steam flow measured value of each boiler combustion system, a control mode of each boiler combustion system and a coal feeding quantity measured value of each boiler combustion system;

step two, calculating the number of the pressure regulating boilers;

counting the number of the boiler combustion systems meeting the condition 1 according to the steam flow measured value of each boiler combustion system and the control mode of each boiler combustion system obtained in the step one, wherein the condition 1 is as follows: the control mode of the boiler combustion system is a coordinated pressure regulating mode, the steam flow is between the lower operation limit and the upper operation limit, the boiler combustion system which meets the condition 1 is used as a pressure regulating boiler, when the number of the pressure regulating boilers is less than two, coordination control is not needed, the boiler combustion system normally operates, when the number of the pressure regulating boilers is more than two, coordination control is needed, and the step III is carried out;

step three, judging an external disturbance state;

calculating whether the steam pressure of the steam main pipe is in an external disturbance state or not by using an external disturbance judgment algorithm according to the steam pressure measured value of the steam main pipe obtained in the step one and the steam flow measured value of each boiler combustion system, judging that the steam pressure is in the external disturbance state when the steam flow is opposite to the steam pressure change direction, automatically adjusting all the boiler combustion systems to be in a feedforward compensation mode at the moment, obtaining an external disturbance feedforward state value of each boiler combustion system, turning to the step four, judging that the steam flow is in a non-external disturbance state when the steam flow is the same as the steam pressure change direction, and turning to the step four when all the boiler combustion systems normally operate;

step four, calculating the total steam flow adjustment amount;

calculating the total steam flow adjustment quantity of the steam main pipe by utilizing an incremental PID algorithm and the steam pressure error of the steam main pipe according to the steam pressure set value of the steam main pipe and the steam pressure measured value of the steam main pipe obtained in the step one, and turning to a step five;

step five, calculating distribution coefficients;

calculating a non-normalized distribution coefficient vector B and a normalized distribution coefficient A by using a normalization algorithm according to the steam flow measured value of each boiler combustion system, the coal feeding amount measured value of each boiler combustion system and the total steam flow adjustment amount obtained in the first step and the total steam flow adjustment amount obtained in the fourth step, wherein when | | | B | | | ≠ 0 represents that the steam pressure coordination requirement is met at the current moment, and when | | | B | | | | is 0, the steam pressure coordination requirement cannot be met at the current moment, setting each boiler combustion system into a non-coordination mode, manually adjusting by a driver, and obtaining a steam flow set value of each boiler combustion system and a control mode set value of each boiler combustion system;

step six, outputting data;

and sending the external disturbance feedforward state value of each boiler combustion system obtained in the third step, the steam flow set value of each boiler combustion system obtained in the fifth step and the control mode set value of each boiler combustion system to each boiler combustion system.

A main pipe steam pressure coordination control system comprises a main pipe coordination controller, wherein the main pipe coordination controller outputs control signals to be sent to a plurality of boiler combustion systems, each boiler combustion system outputs corresponding steam flow to a steam main pipe, and the main pipe coordination controller comprises an information input module, a pressure regulating boiler statistics module, an external disturbance judgment module, a total steam flow adjustment calculation module, a distribution coefficient calculation module and an information output module;

the information input module is simultaneously connected with each boiler combustion system and the steam main pipe, and is used for acquiring a steam pressure set value of the steam main pipe, a steam pressure measured value of the steam main pipe, a steam flow measured value of each boiler combustion system, a control mode of each boiler combustion system and a coal feeding amount measured value of each boiler combustion system, sending the steam pressure measured value of the steam main pipe and the steam flow measured value of each boiler combustion system to the external disturbance judgment module, sending the steam pressure set value of the steam main pipe and the steam pressure measured value of the steam main pipe to the total steam flow adjustment amount calculation module, and sending the steam flow measured value of each boiler combustion system and the coal feeding amount measured value of each boiler combustion system to the distribution coefficient calculation module;

the pressure-regulating boiler counting module is connected with the information input module and used for receiving the steam flow measured value of each boiler combustion system sent by the information input module and the control mode of each boiler combustion system, and counting the number of the boiler combustion systems meeting the condition 1 according to the received data, wherein the condition 1 is as follows: the control mode of the boiler combustion system is a coordinated pressure regulating mode, and the steam flow is between the lower limit of operation and the upper limit of operation; taking the boiler combustion system meeting the condition 1 as a pressure regulating boiler, judging whether coordination is needed according to the number of the pressure regulating boilers, if coordination control is needed, sending a coordination instruction to an external disturbance judgment module, and if coordination control is not needed, normally operating the boiler combustion system;

the external disturbance judgment module is simultaneously connected with the information input module, the pressure regulating boiler statistics module and the information output module, and is used for receiving a steam pressure measured value of the steam main pipe and a steam flow measured value of each boiler combustion system sent by the information input module and a coordination instruction sent by the pressure regulating boiler statistics module, calculating whether the steam pressure of the steam main pipe is in an external disturbance state or not by using an external disturbance judgment algorithm according to received data, and sending an external disturbance feedforward state value of each boiler combustion system to the information output module;

the total steam flow adjustment quantity calculation module is simultaneously connected with the information input module, the pressure regulating boiler statistics module and the distribution coefficient calculation module, and is used for receiving a steam pressure set value of the steam main pipe and a steam pressure measured value of the steam main pipe sent by the information input module and a coordination instruction sent by the pressure regulating boiler statistics module, calculating the total steam flow adjustment quantity of the steam main pipe according to received data by utilizing an incremental PID algorithm and a steam pressure error of the steam main pipe, and sending the total steam flow adjustment quantity to the distribution coefficient calculation module;

the distribution coefficient calculation module is simultaneously connected with the information input module, the total steam flow adjustment quantity calculation module and the information output module, and is used for receiving the steam flow measured value of each boiler combustion system and the coal feeding quantity measured value of each boiler combustion system sent by the information input module and the total steam flow adjustment quantity sent by the total steam flow adjustment quantity calculation module, calculating a non-normalized distribution coefficient vector B and a normalized distribution coefficient A by using a normalization algorithm, and sending a steam flow given value of each boiler combustion system and a control mode given value of each boiler combustion system to the information output module;

and the information output module is simultaneously connected with the external disturbance judgment module, the distribution coefficient calculation module and each boiler combustion system, and is used for receiving the external disturbance feedforward state value of each boiler combustion system sent by the external disturbance judgment module, the steam flow set value of each boiler combustion system and the control mode set value of each boiler combustion system sent by the distribution coefficient calculation module, and sending the received data to each boiler combustion system.

Has the advantages that:

the invention solves the problem of how to reasonably distribute the load from three aspects of the steam pressure coupling problem among a plurality of boilers, the influence of external load disturbance on the steam pressure and the fixed pressure regulating boiler. The invention realizes the dynamic change of the boiler participating in pressure regulation by introducing the control mode weighting coefficient, does not need to fix a certain boiler as the pressure regulating boiler, particularly can correct the control mode weighting coefficient when only two boilers regulate the pressure, and can reduce the influence of steam pressure coupling by using a single boiler to regulate when the steam regulation of the single boiler meets the total steam regulation quantity. In practical application, the coal consumption level is effectively reduced, and the safe, stable and economic operation of the on-site unit is realized.

Drawings

FIG. 1 is a block diagram of a coordinated control system for steam pressure in a main pipe;

FIG. 2 is a flow chart of a bus pressure coordination control calculation;

Detailed Description

The first embodiment is as follows: the coordinated control method for the steam pressure of the main pipe in the embodiment is described with reference to fig. 1 and fig. 2, and comprises the following steps:

step one, acquiring data;

acquiring a steam pressure set value of a steam main pipe 3, a steam pressure measured value of the steam main pipe 3, a steam flow measured value of each boiler combustion system 2, a control mode of each boiler combustion system 2 and a coal feeding quantity measured value of each boiler combustion system 2;

step two, calculating the number of the pressure regulating boilers;

counting the number of the boiler combustion systems 2 meeting the condition 1 according to the measured steam flow value of each boiler combustion system 2 and the control mode of each boiler combustion system 2 obtained in the step one, wherein the condition 1 is as follows: the control mode of the boiler combustion system 2 is a coordinated pressure regulating mode, the steam flow is between the lower operation limit and the upper operation limit, the boiler combustion system 2 meeting the condition 1 is used as a pressure regulating boiler, when the number of the pressure regulating boilers is less than two, coordination control is not needed, the boiler combustion system 2 normally operates, when the number of the pressure regulating boilers is more than two, coordination control is needed, and the step III is shifted;

step three, judging an external disturbance state;

calculating whether the steam pressure of the steam main pipe 3 is in an external disturbance state or not by using an external disturbance judgment algorithm according to the steam pressure measured value of the steam main pipe 3 and the steam flow measured value of each boiler combustion system 2 obtained in the step one, judging that the steam pressure is in the external disturbance state when the steam flow is opposite to the steam pressure change direction, automatically adjusting all the boiler combustion systems 2 to be in a feedforward compensation mode at the moment, obtaining an external disturbance feedforward state value of each boiler combustion system 2, turning to the step four, judging that the steam flow is in a non-external disturbance state when the steam flow is the same as the steam pressure change direction, normally operating all the boiler combustion systems 2, and turning to the step four;

step four, calculating the total steam flow adjustment amount;

calculating the total steam flow adjustment quantity of the steam main pipe 3 by utilizing an incremental PID algorithm and the steam pressure error of the steam main pipe 3 according to the steam pressure set value of the steam main pipe 3 and the steam pressure measured value of the steam main pipe 3 obtained in the step one, and turning to a step five;

step five, calculating distribution coefficients;

according to the measured steam flow value of each boiler combustion system 2, the measured coal feeding value of each boiler combustion system 2 and the total steam flow adjustment value obtained in the first step, calculating a non-normalized distribution coefficient vector B and a normalized distribution coefficient A by using a normalization algorithm, when | | | B | | ≠ 0 represents that the current time meets the coordination requirement of steam pressure, and when | | | B | | | | | | | 0 represents that the current time cannot meet the coordination requirement of steam pressure, setting each boiler combustion system 2 into a non-coordinated mode, and manually adjusting by a driver to obtain the steam flow set value of each boiler combustion system 2 and the control mode set value of each boiler combustion system 2;

step six, outputting data;

and sending the external disturbance feedforward state value of each boiler combustion system 2 obtained in the third step, the steam flow set value of each boiler combustion system 2 obtained in the fifth step and the control mode set value of each boiler combustion system 2 to each boiler combustion system 2.

The second embodiment is as follows: the method for coordinately controlling steam pressure in a main pipe according to the present embodiment will be described with reference to fig. 1 and 2, where in the first step, the steam pressure set value of the steam main pipe 3 is P_sp1；

The measured value of the steam pressure of the steam main pipe 3 is P_y1；

The measured value of the steam flow of the boiler combustion system 2 is D_y0， The measured value of the steam flow to each boiler combustion system 2 is shown, and T is a matrix transpose;

the control mode of the boiler combustion system 2 is M_y0， Showing the control mode specific to each boiler combustion system 2;

the measured value of the coal supply amount of the boiler combustion system 2 is C_y0， Indicating an actual value of the amount of coal fed to each boiler combustion system 2;

the external disturbance feedforward state value of the boiler combustion system 2 is UFb_Dis，Represents an external disturbance feedforward state value specific to each boiler combustion system 2;

the steam flow given value of the boiler combustion system 2 is UD_sp0， Representing a steam flow setpoint specific to each boiler combustion system 2;

the given value of the control mode of the boiler combustion system 2 is UM_sp0，Showing the control mode set point specific to each boiler combustion system 2, the other being the same as the first embodiment.

The third concrete implementation mode: in the third step, a method for determining an external disturbance state is as follows:

k is the current time;

epsilon is a steam pressure external disturbance judgment threshold value, such as 0.1MPa, and the specific numerical value is adjusted according to the actual engineering;

d is the total steam flow of the combustion systems 2 of the plurality of boilers, and the calculation formula is as follows:

when the steam flow and the steam pressure change direction are opposite, judging that the steam flow and the steam pressure change direction are in an external disturbance state, wherein the external disturbance state comprises a positive external disturbance state and a negative external disturbance state; the boiler passes through the feedforward compensation mode, when the unit gets rid of load, outer net load sudden change, can quick adjustment boiler combustion system overcome the external disturbance influence, realizes the stability of the 3 steam pressures of the female pipe of steam to reduce its fluctuation range.

UFb_DisWhen the pressure of the main pipe is in a positive external disturbance state, the pressure of the main pipe is suddenly increased, the safety of the system is influenced, and the steam flow on the main pipe is reduced;

UFb_Diswhen the pressure of the main pipe is in a negative external disturbance state, the pressure of the main pipe is suddenly reduced, the heat efficiency of the system is reduced, and the steam flow on the main pipe is increased;

UFb_Disand (0) indicating a state without external disturbance, and indicating a normal working condition at the time, wherein the boiler combustion systems 2 normally operate, and the rest are the same as those in the first or second embodiment.

The fourth concrete implementation mode: in the fourth step, the method for calculating the total steam flow adjustment amount by using the incremental PID algorithm and the steam pressure error of the steam main pipe 3 includes:

δU_D(k)＝K_p(e(k)-e(k-1))+K_i(e(k))+K_d(e(k)-2e(k-1)+e(k-2)) (3)

wherein, δ U_D(k) Representing the total steam flow adjustment at time k;

K_Pthe specific numerical value is obtained by setting according to engineering experience, such as a critical ratio method or an attenuation curve method;

K_ithe integral control coefficient is obtained by setting a specific numerical value according to engineering experience;

K_dthe specific numerical value is obtained by setting according to engineering experience for the differential control coefficient;

e (k) represents the steam pressure control error of the steam parent pipe 3 at the time k,

e(k)＝P_sp1(k)-P_y1(k) (4)

P_sp1(k) the steam pressure set value of the steam main pipe 3 at the moment k is shown;

P_y1(k) the other points are the same as the first, second or third embodiments, except that the measured value of the steam pressure in the steam header 3 at the time k is shown.

The fifth concrete implementation mode: the coordinated control method for the steam pressure in the main pipe according to the present embodiment is described with reference to fig. 1 and fig. 2, where the fifth step includes: steam flow set value UD of boiler combustion system 2_sp0(k)：

UD_sp0(k)＝ΔUD_sp0(k)+UD_sp0(k-1) (5)

Wherein UD_sp0(k-1) is the steam flow given value of the boiler combustion system 2 at the last moment;

ΔUD_sp0(k) the change quantity of the given value of the steam flow of the boiler combustion system 2 at the previous moment and the current moment;

ΔUD_sp0(k)＝[α₁,α₂,…,α_N]^T*δU_D(k) (6)

distribution coefficient alpha_iI is 1,2, …, N, and satisfies:

n is the number of boiler combustion systems 2;

and calculating distribution coefficients by integrating the running states of the boiler combustion systems 2, wherein the distribution coefficient vector of the steam flow adjustment quantity of each boiler combustion system 2 is recorded as:

A＝[α₁,α₂,…,α_N]^T

non-normalized distribution coefficient vector:

B＝[β₁,β₂,…,β_N]^T

and (3) normalization calculation:

non-normalized coefficient:

wherein i is 1,2, …, N;

weighting coefficients for coal consumption characteristics;

weighting coefficients for the steam flow margin;

weighting coefficients for the control modes;

wherein T is a calculation statistical period;

j is the control calculation time;

the more the steam flow generated by unit coal consumption is, the larger the weighting coefficient is, and the economic performance of the unit is improved; when the calculation time length is less than the statistical period T, the coal consumption characteristic weighting coefficients are the same;

wherein the content of the first and second substances,the steam flow operation upper limit value of a boiler combustion system 2I;

the lower limit value of steam flow operation of a boiler combustion system 2I;

the higher the steam flow adjustment flow of each boiler combustion system 2 accounts for in the total flow adjustment interval, the larger the corresponding steam flow margin weighting coefficient is;

wherein the content of the first and second substances,indicating that the respective boiler combustion system 2 is in a coordinated mode;

indicating that the respective boiler combustion system 2 is in non-coordinated mode;

the introduction of the control mode weighting coefficient can realize the dynamic change of the boiler participating in pressure regulation, a certain boiler combustion system 2 is not required to be fixed to serve as the pressure regulating boiler, particularly, when only two boiler combustion systems 2 are used for pressure regulation, the control mode weighting coefficient can be corrected, and when the steam regulation of a single boiler combustion system 2 meets the total steam regulation amount, the single boiler combustion system 2 is used for regulation, so that the steam pressure coupling influence is reduced. The non-normalized distribution coefficient beta is obtained by multiplying the weighting coefficients_iAnd obtaining a non-normalized distribution coefficient vector B.

And (3) outputting a control mode:

wherein, | B | | ≠ 0 indicates that the steam pressure coordination requirement is satisfied at the current moment;

and if the current time cannot meet the steam pressure coordination requirement, setting each boiler combustion system 2 to be in a non-coordination mode, manually adjusting by a furnace, and the rest of the steps are the same as the first, second, third or fourth specific embodiments.

The sixth specific implementation mode: the main pipe steam pressure coordination control system of the embodiment is described by combining fig. 1 and fig. 2, and comprises a main pipe coordination controller 1, wherein the main pipe coordination controller 1 outputs a control signal to be sent to a plurality of boiler combustion systems 2, each boiler combustion system 2 outputs corresponding steam flow to a steam main pipe 3, in the main pipe steam pressure coordination control system, the steam pressure of the steam main pipe 3 is used as an outer ring control quantity, and the stable control of the steam pressure of the steam main pipe 3 is realized by adjusting the steam flow generated by each boiler combustion system 2, and the main pipe coordination controller 1 comprises an information input module, a pressure-regulating boiler statistic module, an external disturbance judgment module, a total steam flow adjustment quantity calculation module, a distribution coefficient calculation module and an information output module;

the information input module is simultaneously connected with each boiler combustion system 2 and each steam main pipe 3 and is used for acquiring a steam pressure set value of each steam main pipe 3, a steam pressure measured value of each steam main pipe 3, a steam flow measured value of each boiler combustion system 2, a control mode of each boiler combustion system 2 and a coal supply quantity measured value of each boiler combustion system 2, facilitating subsequent calculation, sending the steam pressure measured value of each steam main pipe 3 and the steam flow measured value of each boiler combustion system 2 to the external disturbance judgment module, sending the steam pressure set value of each steam main pipe 3 and the steam pressure measured value of each steam main pipe 3 to the total steam flow adjustment quantity calculation module, and sending the steam flow measured value of each boiler combustion system 2 and the coal supply quantity measured value of each boiler combustion system 2 to the distribution coefficient calculation module.

The pressure regulating boiler statistics module is connected with the information input module and used for receiving the steam flow measured value of each boiler combustion system 2 and the control mode of each boiler combustion system 2 sent by the information input module, and counting the number of the boiler combustion systems 2 meeting the condition 1 according to the received data, wherein the condition 1 is as follows: the control mode of the boiler combustion system 2 is a coordinated pressure regulating mode, and the steam flow is between the lower limit of operation and the upper limit of operation; and (3) taking the boiler combustion system 2 meeting the condition 1 as a pressure regulating boiler, judging whether coordination is needed according to the number of the pressure regulating boilers, if coordination control is needed, sending a coordination instruction to an external disturbance judgment module and a total steam flow regulation calculation module, and if coordination control is not needed, normally operating the boiler combustion system 2.

And the external disturbance judgment module is simultaneously connected with the information input module, the pressure regulating boiler statistics module and the information output module, and is used for receiving the steam pressure measured value of the steam main pipe 3 and the steam flow measured value of each boiler combustion system 2 sent by the information input module, and a coordination instruction sent by the pressure regulating boiler statistics module, calculating whether the steam pressure of the steam main pipe 3 is in an external disturbance state or not by using an external disturbance judgment algorithm according to the received data, and sending the external disturbance feedforward state value of each boiler combustion system 2 to the information output module.

The total steam flow adjustment quantity calculation module is simultaneously connected with the information input module, the pressure regulating boiler statistics module and the distribution coefficient calculation module, and is used for receiving a steam pressure set value of the steam main pipe 3 and a steam pressure measured value of the steam main pipe 3 sent by the information input module and a coordination instruction sent by the pressure regulating boiler statistics module, because a boiler control object has time-varying, nonlinear and hysteresis characteristics, no specific mathematical model exists, an incremental PID algorithm widely applied in control engineering is adopted according to received data, the total steam flow adjustment quantity of the steam main pipe 3 is calculated by utilizing a steam pressure error of the steam main pipe 3, and the total steam flow adjustment quantity is sent to the distribution coefficient calculation module.

And the distribution coefficient calculation module is simultaneously connected with the information input module, the total steam flow adjustment quantity calculation module and the information output module, and is used for receiving the steam flow measured value of each boiler combustion system 2 and the coal feeding quantity measured value of each boiler combustion system 2 sent by the information input module, and the total steam flow adjustment quantity sent by the total steam flow adjustment quantity calculation module, calculating a non-normalized distribution coefficient vector B and a normalized distribution coefficient A by using a normalization algorithm, and sending the steam flow given value of each boiler combustion system 2 and the control mode given value of each boiler combustion system 2 to the information output module.

And the information output module is simultaneously connected with the external disturbance judgment module, the distribution coefficient calculation module and each boiler combustion system 2, and is used for receiving the external disturbance feedforward state value of each boiler combustion system 2 sent by the external disturbance judgment module, the steam flow given value of each boiler combustion system 2 and the control mode given value of each boiler combustion system 2 sent by the distribution coefficient calculation module, and sending the received data to each boiler combustion system 2.

The seventh embodiment: the coordinated control system for the steam pressure of the main pipe 3 according to the present embodiment is described with reference to fig. 1 and 2, wherein the given value of the steam pressure of the main pipe is P_sp1；

The measured value of the steam pressure of the steam main pipe 3 is P_y1；

The measured value of the steam flow of the boiler combustion system 2 is D_y0， The measured value of the steam flow to each boiler combustion system 2 is shown, and T is a matrix transpose;

the control mode of the boiler combustion system 2 is M_y0， Showing the control mode specific to each boiler combustion system 2;

the measured value of the coal supply amount of the boiler combustion system 2 is C_y0， Indicating an actual value of the amount of coal fed to each boiler combustion system 2;

the external disturbance feedforward state value of the boiler combustion system 2 is UFb_Dis，Represents an external disturbance feedforward state value specific to each boiler combustion system 2;

the steam flow given value of the boiler combustion system 2 is UD_sp0， Representing a steam flow setpoint specific to each boiler combustion system 2;

the given value of the control mode of the boiler combustion system 2 is UM_sp0，Showing the control mode set point specific to each boiler combustion system 2, the rest being the same as the sixth embodiment.

The specific implementation mode is eight: with reference to fig. 1 and fig. 2, a coordinated control system for steam pressure in a main pipe according to the present embodiment is described, where a method for determining an external disturbance state by the external disturbance determining module is as follows:

k is the current time;

epsilon is a steam pressure external disturbance judgment threshold value, such as 0.1MPa, and the specific numerical value is adjusted according to the actual engineering;

d is the total steam flow of the multiple boiler combustion systems 2, and the calculation formula is as follows:

when the steam flow and the steam pressure change direction are opposite, judging that the steam flow and the steam pressure change direction are in an external disturbance state, wherein the external disturbance state comprises a positive external disturbance state and a negative external disturbance state; the boiler passes through the feedforward compensation mode, when the unit gets rid of load, outer net load sudden change, can quick adjustment boiler combustion system overcome the external disturbance influence, realizes the stability of the 3 steam pressures of the female pipe of steam to reduce its fluctuation range.

UFb_DisWhen the pressure of the main pipe is in a positive external disturbance state, the pressure of the main pipe is suddenly increased, the safety of the system is influenced, and the steam flow on the main pipe is reduced; UFb_DisWhen the pressure of the main pipe is in a negative external disturbance state, the pressure of the main pipe is suddenly reduced, the heat efficiency of the system is reduced, and the steam flow on the main pipe is increased;

UFb_Dis0, no external disturbance state; at this time, the plurality of boiler combustion systems 2 are normally operated under normal conditions. The others are the same as the sixth or seventh embodiments.

The specific implementation method nine: in the present embodiment, a method for calculating a total steam flow adjustment amount by using an incremental PID algorithm in a total steam flow adjustment amount calculation module and a steam pressure error of a steam main 3 includes:

δU_D(k)＝K_p(e(k)-e(k-1))+K_i(e(k))+K_d(e(k)-2e(k-1)+e(k-2)) (14)

wherein, δ U_D(k) Representing the total steam flow adjustment at time k;

K_pthe specific numerical value is obtained by setting according to engineering experience, such as a critical ratio method or an attenuation curve method;

K_ithe integral control coefficient is obtained by setting a specific numerical value according to engineering experience;

K_dthe specific numerical value is obtained by setting according to engineering experience for the differential control coefficient;

e (k) represents the steam pressure control error of the steam parent pipe 3 at the time k,

e(k)＝P_sp1(k)-P_y1(k) (15)

P_sp1(k) the steam pressure set value of the steam main pipe 3 at the moment k is shown;

P_y1(k) the measured value of the steam pressure of the steam main pipe 3 at the moment k is shown; the others are the same as the embodiments six, seven or eight.

The detailed implementation mode is ten: the coordinated control system for the steam pressure in the main pipe according to the present embodiment is described with reference to fig. 1 and fig. 2, wherein the distribution coefficient calculation module includes:

steam flow set value UD of boiler combustion system 2_sp0(k)：

UD_sp0(k)＝ΔUD_sp0(k)+UD_sp0(k-1) (16)

Wherein UD_sp0(k-1) is the steam flow given value of the boiler combustion system 2 at the last moment;

ΔUD_sp0(k) the change quantity of the given value of the steam flow of the boiler combustion system 2 at the previous moment and the current moment;

ΔUD_sp0(k)＝[α₁,α₂,…,α_N]^T*δU_D(k) (17)

distribution coefficient alpha_iI is 1,2, …, N, and satisfies:

n is the number of boiler combustion systems 2;

and calculating distribution coefficients by integrating the running states of the boiler combustion systems 2, wherein the distribution coefficient vector of the steam flow adjustment quantity of each boiler combustion system 2 is recorded as:

A＝[α₁,α₂,…,α_N]^T

non-normalized distribution coefficient vector:

B＝[β₁,β₂,…,β_N]^T

and (3) normalization calculation:

non-normalized coefficient:

wherein i is 1,2, … N;

weighting coefficients for coal consumption characteristics;

weighting coefficients for the steam flow margin;

weighting coefficients for the control modes;

wherein T is a calculation statistical period;

j is the control calculation time;

the more the steam flow generated by unit coal consumption is, the larger the weighting coefficient is, and the economic performance of the unit is improved; and when the calculation time length is less than the statistical period T, the coal consumption characteristic weighting coefficients are the same.

Wherein the content of the first and second substances,is No. i boiler combustion system 2 steam flowAn upper operating limit value;

the lower limit value of steam flow operation of a boiler combustion system 2I;

the higher the steam flow adjustment flow of each boiler combustion system 2 accounts for in the total flow adjustment interval, the larger the corresponding steam flow margin weighting coefficient.

Wherein the content of the first and second substances,indicating that the respective boiler combustion system 2 is in a coordinated mode;

indicating that the respective boiler combustion system 2 is in non-coordinated mode;

the introduction of the control mode weighting coefficient can realize the dynamic change of the boiler participating in pressure regulation, a certain boiler combustion system 2 is not required to be fixed to serve as the pressure regulating boiler, particularly, when only two boiler combustion systems 2 are used for pressure regulation, the control mode weighting coefficient can be corrected, and when the steam regulation of a single boiler combustion system 2 meets the total steam regulation amount, the single boiler combustion system 2 is used for regulation, so that the steam pressure coupling influence is reduced. The non-normalized distribution coefficient beta is obtained by multiplying the weighting coefficients_iAnd obtaining a non-normalized distribution coefficient vector B.

And (3) outputting a control mode:

wherein, | B | | ≠ 0 means that the current time satisfies the coordination requirement of the steam pressure,

setting the control mode of each boiler combustion system 2 as a non-coordinated mode, and handing over to a driver for manual adjustment; the others are the same as in the sixth, seventh, eighth or ninth embodiments.