CN114704822A - Control method and device of electric heating steam boiler system - Google Patents

Control method and device of electric heating steam boiler system Download PDF

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CN114704822A
CN114704822A CN202210423773.5A CN202210423773A CN114704822A CN 114704822 A CN114704822 A CN 114704822A CN 202210423773 A CN202210423773 A CN 202210423773A CN 114704822 A CN114704822 A CN 114704822A
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transfer function
steam
decoupler
quantities
controlled
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CN114704822B (en
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袁俊球
秦斌
周斌
柴婷逸
陆骞
刘聪
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Changzhou Jintan Jinneng Power Co ltd
State Grid Jiangsu Electric Power Co ltd Innovation And Innovation Center
State Grid Corp of China SGCC
State Grid Jiangsu Electric Power Co Ltd
Changzhou Power Supply Co of State Grid Jiangsu Electric Power Co Ltd
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Changzhou Jintan Jinneng Power Co ltd
State Grid Corp of China SGCC
State Grid Jiangsu Electric Power Co Ltd
Changzhou Power Supply Co of State Grid Jiangsu Electric Power Co Ltd
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B35/00—Control systems for steam boilers
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F30/00—Computer-aided design [CAD]
    • G06F30/20—Design optimisation, verification or simulation
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F2111/00—Details relating to CAD techniques
    • G06F2111/10—Numerical modelling
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F2119/00—Details relating to the type or aim of the analysis or the optimisation
    • G06F2119/08—Thermal analysis or thermal optimisation
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P90/00—Enabling technologies with a potential contribution to greenhouse gas [GHG] emissions mitigation
    • Y02P90/02—Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

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Abstract

The invention provides a control method and a device of an electric heating steam boiler system, which comprises the following steps: determining two mutually coupled quantities to be controlled in the electric heating steam boiler system, wherein the coupling relation between the two mutually coupled quantities to be controlled forms a coupling system; determining two output quantities and two input quantities of a coupling system according to the two mutually coupled quantities to be controlled; determining a transfer function of the coupling system according to the output quantity and the input quantity of the coupling system, and obtaining a transfer function of the first decoupler and a transfer function of the second decoupler according to the transfer function of the coupling system; and decoupling control is carried out on the two mutually coupled controlled variables through the first decoupler and the second decoupler. Therefore, the coupled quantities to be controlled in the electric heating steam boiler system are considered, and the mutually coupled quantities to be controlled are subjected to decoupling control, so that the mutually coupled quantities to be controlled can be relatively independently controlled, and the stable operation of the system is more facilitated.

Description

Control method and device of electric heating steam boiler system
Technical Field
The invention relates to the technical field of electric reactors, in particular to a control method of an electric heating steam boiler system and a control device of the electric heating steam boiler system.
Background
The electric steam heat storage technology solves the problem that an electric steam boiler with high operation cost can not be started any more in daytime after an industrial enterprise bans a coal-fired steam boiler, but low economic steam cost can be obtained, and the requirement of normal production is met. And the problem of high running cost of natural gas is also solved. The whole system is safe and stable in operation, sufficient in steam output, advanced in technology and good in economical efficiency.
As the most critical facilities in the electric steam heat storage technology: the electric heating steam boiler has the advantages of high starting and stopping speed, high steam quality, simplicity in maintenance, small installation space, environmental friendliness and the like, and is more and more widely applied to the fields of industry and electric power markets. The control of an electrically heated steam boiler is therefore of great importance.
Disclosure of Invention
At present, a conventional PID (proportional Integral Differential) controller is adopted for the electric heating steam boiler to ensure the dynamic performance of the system, and the PID adjusting method has the characteristics of simple structure, stability, reliability and the like. However, coupling exists between some variables of the system, so that the coupling parameters are effectively decoupled and controlled simultaneously when the conventional variables are controlled.
The invention provides the following technical scheme for solving the problem that decoupling control cannot be considered in the related technology.
An embodiment of the first aspect of the invention provides a control method of an electric heating steam boiler system, which comprises the following steps: determining two mutually coupled quantities to be controlled in the electric heating steam boiler system, wherein a coupling relation between the two mutually coupled quantities to be controlled forms a coupling system; determining two output quantities and two input quantities of the coupling system according to the two mutually coupled quantities to be controlled; determining a transfer function of the coupling system according to the output quantity and the input quantity of the coupling system, and obtaining a transfer function of a first decoupler and a transfer function of a second decoupler according to the transfer function of the coupling system; and performing decoupling control on the two mutually coupled controlled quantities through the first decoupler and the second decoupler.
In addition, the control method of the electrically heated steam boiler system according to the above embodiment of the present invention may further have the following additional technical features.
According to one embodiment of the invention, the two mutually coupled quantities to be controlled are boiler power and steam temperature, the two input quantities of the coupling system are the opening of a water supplementing valve and the opening of a steam outlet valve, and the two output quantities are actual boiler temperature and actual steam temperature.
According to an embodiment of the invention, the coupling system has a first transfer function, a second transfer function, a third transfer function and a fourth transfer function, the transfer function of the coupling system is determined according to the output quantity and the input quantity of the coupling system, comprising the steps of: according to the input quantity and the output quantity corresponding to each transfer function of the coupling system, wherein the first transfer function is used for representing the relation between the input quantity and the output quantity when the input quantity is the opening degree of a water replenishing valve and the output quantity is actual boiler power, the second transfer function is used for representing the relation between the input quantity and the output quantity when the input quantity is the opening of a water replenishing valve and the output quantity is the actual steam temperature, the third transfer function is used for representing the relation between the input quantity and the output quantity when the input quantity is the opening of the steam outlet valve and the output quantity is the actual boiler power, the fourth transfer function is used for representing the relation between the input quantity and the output quantity when the input quantity is the opening of the steam outlet valve and the output quantity is the actual steam temperature, and the first transfer function to the fourth transfer function all meet the following second-order time lag model:
Figure BDA0003607610650000021
wherein G(s) is a transfer function of the coupling system, a, b and c are coefficients of each order of the transfer function, and L is a hysteresis constant of the transfer function; obtaining a plurality of groups of different input and output measurement values corresponding to each group of the input quantity and the output quantity; and performing parameter identification on the corresponding transfer function by using the plurality of groups of input and output measurement values to obtain each order coefficient and a hysteresis constant of the transfer function.
According to an embodiment of the present invention, the parameter identification of the corresponding transfer function by using the plurality of sets of input/output measurement values comprises the following steps: selecting phase angles and amplitudes of P different frequency points to match the transfer function so as to obtain the following matched model:
Figure BDA0003607610650000031
wherein, ω isnThe frequency of the nth frequency point is n, 1,2, P, and P is more than or equal to 10;
obtaining the following formula I according to the matched model:
a2ω4|G(jω)|2+(2ac-b2)ω2|G(jω)|2+c2|G(jω)|2＝1
and after the formula is converted into a matrix, determining coefficients and hysteresis constants of each order of the transfer function by a least square method.
According to one embodiment of the invention, obtaining a transfer function of a first decoupler and a transfer function of a second decoupler from a transfer function of the coupling system comprises: determining a transfer function of the first decoupler from the first transfer function and the second transfer function, and determining a transfer function of the second decoupler from the third transfer function and the fourth transfer function, wherein the transfer function of the first decoupler and the second decoupler are:
Figure BDA0003607610650000032
Figure BDA0003607610650000033
wherein D is12(s) is the transfer function of the first decoupler, D21(s) is the transfer function of the second decoupler, G1(s) is the first transfer function, G2(s) is said second transfer function, G3(s) is the third transfer function, G4(s) is the fourth transfer function.
According to one embodiment of the invention, the decoupling control of the two mutually coupled controlled variables by the first decoupler and the second decoupler comprises the following steps: acquiring actual boiler power and actual steam temperature output by the electric heating steam boiler system, and acquiring set boiler power and set steam temperature; calculating error power between the set boiler power and the actual boiler, sending the error power to a first controller to obtain the opening of a water replenishing valve, calculating error temperature between the set steam temperature and the actual steam temperature, and sending the error temperature to a second controller to obtain the opening of a steam outlet valve; sending the opening of the water replenishing valve into the first decoupler to obtain a second decoupling signal, and accumulating the opening of the water replenishing valve and the first decoupling signal output by the second decoupler to obtain the opening of the water replenishing valve after decoupling; sending the opening degree of the steam outlet valve into the second decoupler to obtain a first decoupling signal, and accumulating the opening degree of the steam outlet valve and the second decoupling signal output by the first decoupler to obtain the opening degree of the decoupled steam outlet valve; inputting the opening degree of the decoupled water replenishing valve and the opening degree of the decoupled steam outlet valve into the coupling system to obtain actual boiler power and actual steam temperature, and returning to the steps of calculating error power and calculating error temperature to respectively perform closed-loop control on the boiler power and the steam temperature until the actual boiler power is equal to the set boiler power and the actual steam temperature is equal to the set steam temperature.
According to an embodiment of the present invention, the control method of the electrically heated steam boiler system further includes: determining an independent amount to be controlled in the electrically heated steam boiler system; and independently controlling the independent controlled quantity through a third controller.
According to an embodiment of the present invention, the independent controlled amounts include a steam flow rate, and the independently controlling the independent controlled amounts by the third controller specifically includes the steps of: acquiring the actual steam flow of the electric heating steam boiler system, and acquiring the set steam flow; calculating an error flow between the set steam flow and the actual steam flow; inputting the error flow into the third controller to obtain a voltage control quantity, and controlling the electric heating steam boiler system by using the voltage control quantity to enable the electric heating steam boiler system to output an actual steam flow; and returning to the step of calculating the error flow to perform closed-loop control on the steam flow until the actual steam flow is equal to the set steam flow.
According to one embodiment of the invention, the first controller, the second controller and the third controller are PID controllers.
An embodiment of a second aspect of the present invention provides a control device for an electrically heated steam boiler system, including: the first determining module is used for determining two mutually coupled quantities to be controlled in the electric heating steam boiler system, wherein the coupling relation between the two mutually coupled quantities to be controlled forms a coupling system; the second determining module is used for determining two output quantities and two input quantities of the coupling system according to the two mutually coupled quantities to be controlled; the third determining module is used for determining a transfer function of the coupling system according to the output quantity and the input quantity of the coupling system and obtaining a transfer function of the first decoupler and a transfer function of the second decoupler according to the transfer function of the coupling system; and the decoupling control module is used for decoupling and controlling the two mutually coupled controlled variables through the first decoupler and the second decoupler.
According to the technical scheme of the embodiment of the invention, the coupled quantities to be controlled in the electric heating steam boiler system are considered, and the coupled quantities to be controlled are subjected to decoupling control, so that the mutually coupled quantities to be controlled can be relatively independently controlled, and the stable operation of the system is more facilitated.
Drawings
Fig. 1 is a schematic structural view of an electrically heated steam boiler system according to an embodiment of the present invention.
Fig. 2 is a flowchart of a control method of the electric heating steam boiler system according to the embodiment of the present invention.
FIG. 3 is a schematic diagram of an exemplary decoupled control of boiler power and steam temperature in accordance with the present invention.
FIG. 4 is a flow chart of an example of independent control of steam flow according to the present invention.
FIG. 5 is a block diagram illustrating an exemplary embodiment of a control apparatus for an electrically heated steam boiler system.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Fig. 1 is a schematic structural view of an electrically heated steam boiler system according to an embodiment of the present invention.
As shown in fig. 1, the electrically heated steam boiler system includes an electrically heated steam boiler, a softened water tank, various valve openings (including a steam outlet valve opening and a water replenishment valve opening), and the like. The softening water tank is mainly used for supplying water which meets steam production standards, such as pH value, soluble metal ion concentration and the like, to the steam boiler. A temperature sensor, a valve opening sensor and the like are arranged in the system and are responsible for collecting signals for the controller.
Fig. 2 is a flowchart of a control method of the electric heating steam boiler system according to the embodiment of the present invention.
As shown in fig. 2, the control method of the electrically heated steam boiler system includes the following steps S1 to S4.
S1, determining two mutually coupled controlled quantities in the electric heating steam boiler system, wherein the coupling relation between the two mutually coupled controlled quantities forms a coupling system.
The controlled quantity refers to variables needing to be controlled in the electric heating steam boiler system, such as steam temperature and steam flow.
It should be noted that there may be coupling (i.e. mutually coupled quantities to be controlled) or no coupling (i.e. independent quantities to be controlled) in the quantities to be controlled in the electric heating steam boiler system, and the coupling relationship between the coupled quantities to be controlled constitutes a coupling system.
And S2, determining two output quantities and two input quantities of the coupling system according to the two mutually coupled controlled quantities.
Specifically, after two mutually coupled quantities to be controlled are determined, the two mutually coupled quantities to be controlled can be used as output quantities of the coupling system, and control quantities corresponding to the two mutually coupled quantities to be controlled are obtained, for example, the control quantity corresponding to the steam temperature is the opening of the steam outlet valve, so as to obtain two control quantities, and then the two control quantities are used as input quantities of the coupling system, that is, the coupling system is a two-input two-output system.
And S3, determining the transfer function of the coupling system according to the output quantity and the input quantity of the coupling system, and obtaining the transfer function of the first decoupler and the transfer function of the second decoupler according to the transfer function of the coupling system.
It will be appreciated that the transfer function is used to characterize the relationship between the output and input quantities of the system.
Specifically, since the coupling system is a two-input two-output system, four transfer functions are required to describe the coupling system according to the coupling relationship. After the transfer functions of the coupling system are obtained according to the output quantity and the input quantity, the transfer functions of the two decouplers are obtained through calculation according to the producing area function of the coupling functions.
And S4, decoupling and controlling the two mutually coupled controlled variables through the first decoupler and the second decoupler.
Specifically, in order to realize decoupling control on two mutually coupled controlled variables, after transfer functions of a first decoupler and a second decoupler are determined, the first decoupler and the second decoupler are used for decoupling control on the two mutually coupled controlled variables, decoupling control on a coupling system is realized, and relatively independent control on the mutually coupled controlled variables can be realized through decoupling.
Therefore, the control method of the electric heating steam boiler system in the embodiment of the invention considers that the coupled quantities to be controlled exist in the electric heating steam boiler system, and performs decoupling control on the mutually coupled quantities to be controlled, so that the mutually coupled quantities to be controlled can be relatively independently controlled, and the stable operation of the system is more facilitated.
It should be noted that the two quantities or variables to be controlled that are coupled to each other in the electric heating steam boiler system may be the boiler power and the steam flow. And the opening of the steam valve and the opening of the water replenishing valve can influence the power of the boiler and the temperature of outlet steam.
That is, in one embodiment of the present invention, the two mutually coupled quantities to be controlled are the boiler power and the steam temperature, the two input quantities of the coupling system are the opening of the water replenishing valve and the opening of the steam outlet valve, and the two output quantities are the actual boiler temperature and the actual steam temperature.
Specifically, after determining that two mutually coupled to-be-controlled quantities are boiler power and steam temperature, the control quantities of the boiler power and the steam temperature in the system can be determined, where the control quantities are a water replenishing valve opening and a steam outlet valve opening, so that when the two mutually coupled to-be-controlled quantities are the boiler power and the steam temperature, two input quantities of the coupling system are the water replenishing valve opening and the steam outlet valve opening, and two output quantities are actual boiler temperature and actual steam temperature, that is: when the opening of a water replenishing valve is input into the coupling system, the coupling system outputs corresponding actual boiler power and actual steam temperature; when the opening of the steam outlet valve is input into the coupling system, the coupling system outputs corresponding actual boiler power and actual steam temperature; when the opening of the water replenishing valve and the opening of the steam outlet valve are input into the coupling system, the coupling system outputs corresponding actual boiler power and actual steam temperature.
In an embodiment of the present invention, the coupling system has a first transfer function, a second transfer function, a third transfer function and a fourth transfer function, and the determining the transfer function of the coupling system according to the output quantity and the input quantity of the coupling system in the step S3 may include the following steps: according to the input quantity and the output quantity corresponding to each transfer function of the coupling system, a first transfer function is used for representing the relation between the input quantity and the output quantity when the input quantity is the opening of a water replenishing valve and the output quantity is actual boiler power, a second transfer function is used for representing the relation between the input quantity and the output quantity when the input quantity is the opening of the water replenishing valve and the output quantity is actual steam temperature, a third transfer function is used for representing the relation between the input quantity and the output quantity when the input quantity is the opening of a steam outlet valve and the output quantity is actual boiler power, a fourth transfer function is used for representing the relation between the input quantity and the output quantity when the input quantity is the opening of the steam outlet valve and the output quantity is actual steam temperature, and the first transfer function to the fourth transfer function all meet the following second-order time-lag model:
Figure BDA0003607610650000081
wherein G(s) is a transfer function of the coupling system, a, b and c are coefficients of each order of the transfer function, and L is a hysteresis constant of the transfer function; obtaining a plurality of groups of different input and output measurement values corresponding to each group of input quantity and output quantity; and carrying out parameter identification on the corresponding transfer function by utilizing the multiple groups of input and output measurement values to obtain each order coefficient and hysteresis constant of the transfer function.
Further, the parameter identification of the corresponding transfer function by using the multiple groups of input and output measurement values comprises the following steps: selecting phase angles and amplitudes of P different frequency points to match a transfer function so as to obtain the following matched model:
Figure BDA0003607610650000082
wherein, ω isnThe frequency of the nth frequency point is n, 1,2, P, and P is more than or equal to 10; obtaining the following formula I according to the matched model:
a2ω4|G(jω)|2+(2ac-b2)ω2|G(jω)|2+c2|G(jω)|2＝1 (3)
after the formula is converted into a matrix, coefficients of each order of the transfer function and a hysteresis constant are determined by a least square method.
Specifically, the coupling system is a two-input and two-output system, so that the coupling system can have four transfer functions, namely a first transfer function, a second transfer function, a third transfer function and a fourth transfer function, the transfer function of the steam outlet valve opening or the water filling valve opening corresponding to the boiler power or the steam temperature can be obtained according to the operation mechanism of the electric heating steam boiler system, and the transfer function meets a second-order time-lag system, and the second-order time-lag model is a formula (1), so that 4 parameters needing to be identified for each transfer function can be determined to be coefficients a, b and c of each order and a lag constant L.
And then obtaining different input and output measurement values (namely the actually measured input quantity and the corresponding output quantity) corresponding to each group of input quantity and output quantity, selecting the phase angle and amplitude of P different frequency points to match the model of the formula (1) to obtain the model of the formula (2), and respectively splitting the formula (2) into an amplitude relation and a phase angle relation through squaring to obtain the amplitude relation represented by the formula (3).
Equation (3) is then converted to the following matrix form:
Φθ＝Γ (4)
in the formula, each matrix is:
Figure BDA0003607610650000091
Figure BDA0003607610650000092
substituting equations (5) and (6) into the following least squares equation:
θ＝(ΦTΦ)-1ΦTΓ (7)
determining a matrix θ containing parameters a, b, c:
Figure BDA0003607610650000101
and then the matrix of the parameters a, b and c is solved reversely:
Figure BDA0003607610650000102
and obtaining a hysteresis constant L by using a least square method again:
Figure BDA0003607610650000103
all four parameters a, b, c and L of the transfer function have been solved up to this point.
The first transfer function G of the coupling system can be obtained by repeating the formulas (1) to (10) for four times1(s) a second transfer function G2(s) third transfer function G3(s) and a fourth transfer function G4The coefficients of each order and the hysteresis constant of(s) are respectively:
Figure BDA0003607610650000104
wherein, a1、b1And c1Coefficients of respective orders, L, being first transfer functions1Is the hysteresis constant of the first transfer function, a2、b2And c2Coefficients of respective orders, L, both being second transfer functions2Is the hysteresis constant of the second transfer function, a3、b3And c3Coefficients of respective orders, L, both being third transfer functions3Is the hysteresis constant of the third transfer function, a4、b4And c4Coefficients of respective orders, L, being fourth transfer functions4Is the hysteresis constant of the fourth transfer function.
Further, the obtaining the transfer function of the first decoupler and the transfer function of the second decoupler from the transfer function of the coupling system in step S4 may include: determining a transfer function of the first decoupler according to the first transfer function and the second transfer function, and determining a transfer function of the second decoupler according to the third transfer function and the fourth transfer function, wherein the transfer function of the first decoupler and the transfer function of the second decoupler are:
Figure BDA0003607610650000111
Figure BDA0003607610650000112
wherein D is12(s) is the transfer function of the first decoupler, D21(s) transfer function of second decouplerAnd (4) counting.
And further obtaining a decoupling control matrix D of the coupling system as follows:
Figure BDA0003607610650000113
and decoupling the four transfer functions of the coupling system through a decoupling control matrix so as to realize independent control on the quantity to be controlled.
The transfer function D of the first decoupler is thus obtained12(s) and transfer function D of the second decoupler21(S) is followed by step S4 to achieve decoupled control of boiler power and steam temperature.
In an example of the present invention, the step S4 may include the steps of: acquiring actual boiler power and actual steam temperature output by an electric heating steam boiler system, and acquiring set boiler power and set steam temperature; calculating the error power between the set boiler power and the actual boiler, sending the error power to the first controller to obtain the opening of the water replenishing valve, calculating the error temperature between the set steam temperature and the actual steam temperature, and sending the error temperature to the second controller to obtain the opening of the steam outlet valve; sending the opening of the water replenishing valve into the first decoupler to obtain a second decoupling signal, and accumulating the opening of the water replenishing valve and the first decoupling signal output by the second decoupler to obtain the opening of the water replenishing valve after decoupling; sending the opening degree of the steam outlet valve into a second decoupler to obtain a first decoupling signal, and accumulating the opening degree of the steam outlet valve and a second decoupling signal output by the first decoupler to obtain the opening degree of the decoupled steam outlet valve; and inputting the opening of the decoupled water replenishing valve and the opening of the decoupled steam outlet valve into a coupling system to obtain actual boiler power and actual steam temperature, and returning to the steps of calculating error power and error temperature to perform closed-loop control on the boiler power and the steam temperature respectively until the actual boiler power is equal to the set boiler power and the actual steam temperature is equal to the set steam temperature.
Wherein the first controller and the second controller may be PID (proportional Integral Differential) controllers.
The set boiler power is a preset boiler power set value which needs to be reached by the electric heating steam boiler system, and the set steam temperature is a preset steam temperature set value which needs to be reached by the electric heating steam boiler system.
Specifically, as shown in fig. 3, first, the actual boiler power P and the actual steam temperature T of the electric heating steam boiler system may be collected, the set boiler power P and the set steam temperature T may be obtained, the difference between P and P is obtained to obtain the error power, the error power is sent to the first controller, and the first controller outputs the water compensating valve opening m1Obtaining error temperature by making difference between T and T, sending the error temperature to the second controller, and outputting the opening m of the steam outlet valve by the second controller2Then, m is added1Is fed into the first decoupler to obtain a second decoupling signal d2And m is1First decoupling signal d from the output of the second decoupler1Accumulating to obtain the opening degree mu of the decoupled water compensating valve1At the same time, m is2Is fed into a second decoupler to obtain a first decoupling signal d1And m is2Second decoupling signal d from first decoupler output2Accumulating to obtain the opening mu of the decoupled steam outlet valve2Then, the opening degree mu of the decoupled water supply valve is measured1And the opening degree mu of the decoupled steam outlet valve2And the control flow is finished when the actual boiler power output by the coupling system is equal to the set boiler power and the actual steam temperature is equal to the set steam temperature, so that decoupling control of the boiler power and the steam temperature is realized.
When the actual boiler power is equal to the set boiler power, adjusting the water replenishing valve according to the opening of the water replenishing valve acting on the coupling system at the moment, for example, adjusting the opening of the water replenishing valve to 50%; when the actual steam temperature is equal to the set steam temperature, the steam outlet valve is adjusted according to the opening of the steam outlet valve acting on the coupling system at that time, for example, the opening of the steam outlet valve may be adjusted to 60%.
It should be noted that, how to control the two mutually coupled controlled quantities is described above, the electric heating steam boiler system further includes an independent controlled quantity, that is, there is no coupled controlled quantity, and the embodiment of the present invention further controls the independent controlled quantity.
That is, in one embodiment of the present invention, a control method of an electrically heated steam boiler system, further includes: determining the independent quantity to be controlled in the electric heating steam boiler system; and independently controlling the independent quantity to be controlled by a third controller.
Wherein the third controller may be a PID controller.
Specifically, since the independent controlled quantities have no coupling phenomenon, at least one independent controlled quantity can be subjected to conventional PID control.
Further, the independent amount to be controlled comprises steam flow, and the independent amount to be controlled through the third controller specifically comprises the following steps: acquiring the actual steam flow of the electric heating steam boiler system, and acquiring the set steam flow; calculating the error flow between the set steam flow and the actual steam flow; inputting the error flow into a third controller to obtain a voltage control quantity, and controlling the electric heating steam boiler system by the voltage control quantity to enable the electric heating steam boiler system to output an actual steam flow; and returning to the step of calculating the error flow to perform closed-loop control on the steam flow until the actual steam flow is equal to the set steam flow.
The set steam flow is a preset steam flow set value which needs to be controlled by the electric heating steam boiler system.
Specifically, as shown in fig. 4, the set steam flow F is differentiated from the actual steam flow F of the system to obtain an error flow, which is sent to the third controller to output the voltage control amount m3And controlling the voltage by an amount m3Acting on the panAnd the boiler power supply is used for changing the boiler voltage u, further controlling the boiler system to output the actual steam flow, feeding back the actual steam flow to form closed-loop control of the steam flow, and ending the control of the steam flow until the actual steam flow is equal to the set steam flow.
And when the actual steam flow is equal to the set steam flow, adjusting the three-phase power supply of the boiler system according to the voltage control quantity acting on the boiler power supply at the moment.
In summary, the embodiments of the present invention perform different controls on different quantities to be controlled, and can perform relatively independent control, i.e. decoupling control, on mutually coupled parameters in an electrical heating steam boiler system; meanwhile, PID control is adopted for parameters without coupling, so that stable operation of the whole system is realized.
Corresponding to the control method of the electric heating steam boiler system of the above embodiment, the invention also provides a control device of the electric heating steam boiler system.
FIG. 5 is a block diagram illustrating an exemplary embodiment of a control apparatus for an electrically heated steam boiler system.
As shown in fig. 5, the control device of the electric heating steam boiler system includes: a first determination module 10, a second determination module 20, a third determination module 30, and a decoupling control module 40.
The first determining module 10 is configured to determine two mutually coupled quantities to be controlled in the electric heating steam boiler system, wherein a coupling relationship between the two mutually coupled quantities to be controlled constitutes a coupling system; the second determining module 20 is configured to determine two output quantities and two input quantities of the coupled system according to the two mutually coupled quantities to be controlled; the third determining module 30 is configured to determine a transfer function of the coupled system according to the output quantity and the input quantity of the coupled system, and obtain a transfer function of the first decoupler and a transfer function of the second decoupler according to the transfer function of the coupled system; the decoupling control module 40 is configured to perform decoupling control on the two mutually coupled controlled quantities through the first decoupler and the second decoupler.
It should be noted that, for the specific implementation and implementation principle of the control device of the electrical heating steam boiler system, reference may be made to the specific implementation of the control method of the electrical heating steam boiler system, and detailed description is omitted here to avoid redundancy.
The control device of the electric heating steam boiler system in the embodiment of the invention considers that the coupled quantities to be controlled exist in the electric heating steam boiler system, and performs decoupling control on the mutually coupled quantities to be controlled, so that the mutually coupled quantities to be controlled can be relatively independently controlled, and the stable operation of the system is more facilitated.
In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. The meaning of "plurality" is two or more unless specifically limited otherwise.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.
Any process or method descriptions in flow charts or otherwise described herein may be understood as representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or steps of the process, and alternate implementations are included within the scope of the preferred embodiment of the present invention in which functions may be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the present invention.
It should be understood that portions of the present invention may be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, the various steps or methods may be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, any one or combination of the following techniques, which are known in the art, may be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application specific integrated circuit having an appropriate combinational logic gate circuit, a Programmable Gate Array (PGA), a Field Programmable Gate Array (FPGA), or the like.
It will be understood by those skilled in the art that all or part of the steps carried by the method for implementing the above embodiments may be implemented by hardware related to instructions of a program, which may be stored in a computer readable storage medium, and when the program is executed, the program includes one or a combination of the steps of the method embodiments. In addition, functional units in the embodiments of the present invention may be integrated into one processing module, or each unit may exist alone physically, or two or more units are integrated into one module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode. The integrated module, if implemented in the form of a software functional module and sold or used as a stand-alone product, may also be stored in a computer readable storage medium.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.

Claims (10)

1. A method of controlling an electrically heated steam boiler system, comprising the steps of:
determining two mutually coupled quantities to be controlled in the electric heating steam boiler system, wherein a coupling relation between the two mutually coupled quantities to be controlled forms a coupling system;
determining two output quantities and two input quantities of the coupling system according to the two mutually coupled quantities to be controlled;
determining a transfer function of the coupling system according to the output quantity and the input quantity of the coupling system, and obtaining a transfer function of a first decoupler and a transfer function of a second decoupler according to the transfer function of the coupling system;
and performing decoupling control on the two mutually coupled controlled quantities through the first decoupler and the second decoupler.
2. The control method of an electrically heated steam boiler system as set forth in claim 1, wherein the two mutually coupled quantities to be controlled are boiler power and steam temperature, and the two input quantities of the coupled system are a water replenishment valve opening and a steam outlet valve opening, and the two output quantities are actual boiler temperature and actual steam temperature.
3. A method of controlling an electrically heated steam boiler system according to claim 2, wherein the coupling system has a first transfer function, a second transfer function, a third transfer function and a fourth transfer function, the transfer function of the coupling system being determined from the output and input quantities of the coupling system, comprising the steps of:
according to the input quantity and the output quantity corresponding to each transfer function of the coupling system, wherein the first transfer function is used for representing the relation between the input quantity and the output quantity when the input quantity is the opening degree of a water replenishing valve and the output quantity is actual boiler power, the second transfer function is used for representing the relation between the input quantity and the output quantity when the input quantity is the opening of the water replenishing valve and the output quantity is the actual steam temperature, the third transfer function is used for representing the relation between the input quantity and the output quantity when the input quantity is the opening of the steam outlet valve and the output quantity is the actual boiler power, the fourth transfer function is used for representing the relation between the input quantity and the output quantity when the input quantity is the opening of the steam outlet valve and the output quantity is the actual steam temperature, and the first transfer function to the fourth transfer function all meet the following second-order time lag model:
Figure FDA0003607610640000021
wherein G(s) is a transfer function of the coupling system, a, b and c are coefficients of each order of the transfer function, and L is a hysteresis constant of the transfer function;
obtaining a plurality of groups of different input and output measurement values corresponding to each group of the input quantity and the output quantity;
and carrying out parameter identification on the corresponding transfer function by utilizing the multiple groups of input and output measurement values to obtain each order coefficient and hysteresis constant of the transfer function.
4. The method of controlling an electrically heated steam boiler system as set forth in claim 3, wherein the parameter identification of the corresponding transfer function using the plurality of sets of input and output measurements comprises the steps of:
selecting phase angles and amplitudes of P different frequency points to match the transfer function so as to obtain the following matched model:
Figure FDA0003607610640000022
wherein, ω isnThe frequency of the nth frequency point is n, 1,2, P, and P is more than or equal to 10;
obtaining the following formula I according to the matched model:
a2ω4|G(jω)|2+(2ac-b2)ω2|G(jω)|2+c2|G(jω)|2＝1
and after the formula is converted into a matrix, determining coefficients and hysteresis constants of each order of the transfer function by a least square method.
5. The method of controlling an electrically heated steam boiler system as set forth in claim 3, wherein deriving the transfer function of the first decoupler and the transfer function of the second decoupler from the transfer function of the coupling system comprises:
determining a transfer function of the first decoupler from the first transfer function and the second transfer function, and determining a transfer function of the second decoupler from the third transfer function and the fourth transfer function, wherein the transfer function of the first decoupler and the second decoupler are:
Figure FDA0003607610640000031
Figure FDA0003607610640000032
wherein D is12(s) is the transfer function of the first decoupler, D21(s) is the transfer function of the second decoupler, G1(s) is the first transfer function, G2(s) is said second transfer function, G3(s) is the third transfer function, G4(s) is the fourth transfer function.
6. The control method of an electrically heated steam boiler system according to claim 2, wherein the decoupling control of the two mutually coupled quantities to be controlled by the first and second decouplers comprises the steps of:
acquiring actual boiler power and actual steam temperature output by the electric heating steam boiler system, and acquiring set boiler power and set steam temperature;
calculating error power between the set boiler power and the actual boiler, sending the error power to a first controller to obtain the opening of a water replenishing valve, calculating error temperature between the set steam temperature and the actual steam temperature, and sending the error temperature to a second controller to obtain the opening of a steam outlet valve;
sending the opening of the water replenishing valve into the first decoupler to obtain a second decoupling signal, and accumulating the opening of the water replenishing valve and the first decoupling signal output by the second decoupler to obtain the opening of the water replenishing valve after decoupling;
sending the opening degree of the steam outlet valve into the second decoupler to obtain a first decoupling signal, and accumulating the opening degree of the steam outlet valve and the second decoupling signal output by the first decoupler to obtain the opening degree of the decoupled steam outlet valve;
inputting the opening degree of the decoupled water replenishing valve and the opening degree of the decoupled steam outlet valve into the coupling system to obtain actual boiler power and actual steam temperature, and returning to the steps of calculating error power and calculating error temperature to respectively perform closed-loop control on the boiler power and the steam temperature until the actual boiler power is equal to the set boiler power and the actual steam temperature is equal to the set steam temperature.
7. The control method of an electrically heated steam boiler system as set forth in claim 1, further comprising:
determining an independent amount to be controlled in the electric heating steam boiler system;
and independently controlling the independent controlled quantity through a third controller.
8. The method of claim 7, wherein the independent controlled quantity comprises a steam flow, and the independent control of the independent controlled quantity by the third controller specifically comprises the steps of:
acquiring the actual steam flow of the electric heating steam boiler system, and acquiring the set steam flow;
calculating an error flow between the set steam flow and the actual steam flow;
inputting the error flow into the third controller to obtain a voltage control quantity, and controlling the electric heating steam boiler system by using the voltage control quantity to enable the electric heating steam boiler system to output an actual steam flow;
and returning to the step of calculating the error flow to perform closed-loop control on the steam flow until the actual steam flow is equal to the set steam flow.
9. The control method of an electrically heated steam boiler system as set forth in claim 7, wherein said first controller, said second controller and said third controller are PID controllers.
10. A control device for an electrically heated steam boiler system, comprising:
the first determining module is used for determining two mutually coupled quantities to be controlled in the electric heating steam boiler system, wherein the coupling relation between the two mutually coupled quantities to be controlled forms a coupling system;
the second determining module is used for determining two output quantities and two input quantities of the coupling system according to the two mutually coupled quantities to be controlled;
the third determining module is used for determining a transfer function of the coupling system according to the output quantity and the input quantity of the coupling system and obtaining a transfer function of the first decoupler and a transfer function of the second decoupler according to the transfer function of the coupling system;
and the decoupling control module is used for decoupling and controlling the two mutually coupled controlled variables through the first decoupler and the second decoupler.
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117028960A (en) * 2023-09-27 2023-11-10 国网江苏省电力有限公司常州供电分公司 Closed circulation steam generating device with heat storage function
CN117109346A (en) * 2023-10-25 2023-11-24 国网江苏省电力有限公司常州供电分公司 Steam heat storage tank and heat preservation device thereof
CN117588736A (en) * 2024-01-18 2024-02-23 常州高凯电子有限公司 Control system and method for piezoelectric type high-temperature steam generator

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104656699A (en) * 2015-02-13 2015-05-27 华中科技大学 Multichannel decoupling temperature control method
CN105739309A (en) * 2016-02-02 2016-07-06 西安西热控制技术有限公司 Unit coordinated control master control system decoupling compensation control method
CN107390515A (en) * 2017-08-01 2017-11-24 东华大学 The boiler combustion control system that predictive PI algorithm and multivariable decoupling are combined
CN110107879A (en) * 2019-04-01 2019-08-09 国网河南省电力公司电力科学研究院 Boiler heat storage parameter identification method and system
CN111765447A (en) * 2020-07-14 2020-10-13 安徽工业大学 Power generation boiler main steam temperature control method and system based on multivariable decoupling
CN112594776A (en) * 2020-12-30 2021-04-02 华电郑州机械设计研究院有限公司 Control method and system suitable for load adjustment of heat supply unit

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104656699A (en) * 2015-02-13 2015-05-27 华中科技大学 Multichannel decoupling temperature control method
CN105739309A (en) * 2016-02-02 2016-07-06 西安西热控制技术有限公司 Unit coordinated control master control system decoupling compensation control method
CN107390515A (en) * 2017-08-01 2017-11-24 东华大学 The boiler combustion control system that predictive PI algorithm and multivariable decoupling are combined
CN110107879A (en) * 2019-04-01 2019-08-09 国网河南省电力公司电力科学研究院 Boiler heat storage parameter identification method and system
CN111765447A (en) * 2020-07-14 2020-10-13 安徽工业大学 Power generation boiler main steam temperature control method and system based on multivariable decoupling
CN112594776A (en) * 2020-12-30 2021-04-02 华电郑州机械设计研究院有限公司 Control method and system suitable for load adjustment of heat supply unit

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117028960A (en) * 2023-09-27 2023-11-10 国网江苏省电力有限公司常州供电分公司 Closed circulation steam generating device with heat storage function
CN117109346A (en) * 2023-10-25 2023-11-24 国网江苏省电力有限公司常州供电分公司 Steam heat storage tank and heat preservation device thereof
CN117109346B (en) * 2023-10-25 2024-01-02 国网江苏省电力有限公司常州供电分公司 Steam heat storage tank and heat preservation device thereof
CN117588736A (en) * 2024-01-18 2024-02-23 常州高凯电子有限公司 Control system and method for piezoelectric type high-temperature steam generator
CN117588736B (en) * 2024-01-18 2024-05-10 常州高凯电子有限公司 Control system and method for piezoelectric type high-temperature steam generator

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