Process-oriented forward acceleration device and system controller
By using a process-oriented forward acceleration device and system controller, the problem of forward overheating lag in the superheated steam temperature control system of thermal power units has been solved, and rapid response and effective suppression of forward deviation have been achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ELECTRIC POWER RES INST OF GUANGDONG POWER GRID CO LTD
- Filing Date
- 2026-02-12
- Publication Date
- 2026-05-12
AI Technical Summary
There is a positive overheating problem in the superheated steam temperature control system of thermal power units. The existing one-position control method has control lag and limited effectiveness.
The controller of the process-oriented positive acceleration device and system includes a first adder, a limiting integrator, a differentiator, and a positive output controller. The integrator output is limited by the limiting integrator controller, and the negative signal is filtered out by the positive output controller. The first adder works in conjunction with the external process signal to add the integrated external process signal, thereby achieving advance of the positive control quantity.
It effectively suppresses positive overheating in the overheated steam temperature control system, reduces hysteresis problems, achieves rapid response to positive deviations, and improves control performance.
Smart Images
Figure CN122015077A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of process control technology, and in particular to a controller for a process-oriented forward acceleration device and system. Background Technology
[0002] In process control practice, such as in thermal power units, the superheated steam temperature control system frequently experiences overheating issues, with positive overheating being particularly severe. Current technology employs a one-position control method to address this issue. This method increases the opening of the desuperheating water valve by a fixed amount when the positive deviation of the superheated steam temperature exceeds a certain threshold. The main problem with this approach is control lag, resulting in limited effectiveness. Because it takes time for the superheated steam temperature to rise from zero deviation to a certain positive deviation, this leads to a lag in the system's process control. Summary of the Invention
[0003] This invention provides a controller for a process-oriented forward acceleration device and system, which is applied to the superheated steam temperature control system of a thermal power unit. It can advance the forward control quantity and has a good effect on suppressing the forward overheating of the superheated steam temperature control system.
[0004] To achieve the above objectives, a first aspect of this application provides a process-oriented forward acceleration device, including a first addition stage, a limiting integrator, a differentiator, a forward output controller, and a second addition stage; the limiting integrator includes an integrator and an integrator limiting controller; the integrator limiting controller is used to limit the output of the integrator; The first input terminal of the first adder is used to receive external process signals; the second input terminal of the first adder is connected to the output terminal of the integrator; the output terminal of the first adder is connected to the input terminal of the integrator and the input terminal of the differentiator; the output terminal of the differentiator is connected to the input terminal of the positive output controller; the output terminal of the positive output controller is connected to the first input terminal of the second adder; the second input terminal of the second adder is used to receive external process signals; the output terminal of the second adder is used to output the external process signal superimposed with the positive signal. The first addition stage is used to add the output signal of the integrator and the external process signal to accelerate the external process signal and output an acceleration signal to the differentiator.
[0005] In one possible implementation of the first aspect, the positive output controller is used to extract the positive signal from the output signal of the differentiator and output it to the first input terminal of the second adder.
[0006] In one possible implementation of the first aspect, the differentiator is used to extract the differential signal from the acceleration signal.
[0007] In one possible implementation of the first aspect, the second addition step is used to add the positive signal to the external process signal and output the external process signal after superimposing the positive signal through the output terminal.
[0008] In one possible implementation of the first aspect, the transfer function of the integrator limiting controller is: ,in, I ( t () is the output signal of the integrator. PV IN ( t ) represents the external process signal. s For the Laplace operator, T I is the integration time constant.
[0009] In one possible implementation of the first aspect, the transfer function of the positive output controller is: , in, FOC ( t ) is the output signal of the positive output controller. D ( t ) is the output signal of the differentiator.
[0010] In one possible implementation of the first aspect, the transfer function of the differentiator is: , in, D ( s Let be the transfer function of the differentiator. s For the Laplace operator, T D is the differential time constant.
[0011] In one possible implementation of the first aspect, the transfer function of the integrator is: , in, I ( s Let be the transfer function of the integrator, and s be the Laplace operator. T I is the integration time constant.
[0012] A second aspect of this application provides a controller for a process-oriented forward acceleration system, applied to the aforementioned plurality of error calculation units, including: It includes a cascade proportional controller, a fastest integrator, a third adder, a process-oriented positive acceleration device as described above, and a negative proportional element. The input terminal of the cascade proportional controller receives the deviation signal between the process input and the process output. The output terminal of the cascade proportional controller is connected to the input terminal of the fastest integrator and the input terminal of the process-oriented positive acceleration device. The output terminal of the fastest integrator is connected to the first input terminal of the third adder. The second input terminal of the third adder is connected to the output terminal of the process-oriented positive acceleration device. The output terminal of the third adder is connected to the input terminal of the negative proportional element. The negative proportional element is used to output a control signal to the control process, and the process output is obtained at the output end of the control process.
[0013] Compared to existing technologies, the present invention provides a controller for a process-oriented forward acceleration device and system. Addressing the hysteresis problem caused by process signal deviations, it utilizes a first adder to add the integrated external process signal to the external process signal, advancing the positive control quantity and accelerating the external process signal. A positive output controller filters out negative signals, ensuring the positive direction of the superimposed signal in the second adder. The first adder and the positive output controller work together to perform limited positive and lead processing on the process signal, accelerating the formation of a positive deviation in a given process. Furthermore, an integrator limiting controller limits the integrator's output, ensuring its convergence. Attached Figure Description
[0014] Figure 1 This is a schematic diagram of the structure of a process-oriented forward acceleration device provided in an embodiment of the present invention; Figure 2 This is a diagram showing the control results of a fourth-order inertial process system before and after the addition of a positive acceleration device in one embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of a process-oriented forward acceleration system controller according to an embodiment of the present invention; Figure 4 This is a diagram showing the control results of the superheated steam temperature control system before and after the addition of a positive acceleration device in one embodiment of the present invention. Detailed Implementation
[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0016] Please see Figure 1 An embodiment of the present invention provides a process-oriented forward acceleration device, including a first addition stage 1, a limiting integrator, a differentiator 3, a forward output controller 4, and a second addition stage 5; the limiting integrator includes an integrator 20 and an integrator limiting controller 21; the integrator limiting controller 21 is used to limit the output of the integrator 20.
[0017] The first input terminal of the first adder 1 is used to receive external process signals. The second input terminal of the first adder 1 is connected to the output terminal of the integrator 20. The output terminal of the first adder 1 is connected to the input terminal of the integrator 20 and the input terminal of the differentiator 3. The output terminal of the differentiator 3 is connected to the input terminal of the positive output controller. The output terminal of the positive output controller is connected to the first input terminal of the second adder 5. The second input terminal of the second adder 5 is used to receive external process signals. The output terminal of the second adder 5 is used to output the external process signal superimposed with the positive signal.
[0018] The first addition stage 1 is used to add the output signal of the integrator 20 and the external process signal to accelerate the external process signal and output an acceleration signal to the differentiator 3.
[0019] Integrator 20 has an acceleration effect in the positive feedback loop (first adder 1). In this structure, the output of integrator 20 does not converge, so the output signal of integrator 20 needs to be limited by integrator limiter controller 21.
[0020] The function of differentiator 3 is to extract the differential signal output by integrator 20, which enhances the output signal of the first adder 1 by providing a kind of advance observation.
[0021] The positive output controller 4 takes the positive signal from the differentiator 3. For the process positive acceleration observer, there is no need to output a negative signal.
[0022] The purpose of the second addition stage (second addition stage 5) is to superimpose the positive signal of the positive output controller 4 with the input signal.
[0023] It should be noted that V H This is the upper limit of the output signal of integrator 20, in dimensionless units; V L This is the lower limit of the output signal of integrator 20, in dimensionless units.
[0024] The forward acceleration device provided in this embodiment of the invention can also be called a process forward acceleration observer (PFAO). It achieves forward acceleration observation of process signals through the positive feedback loop of the first adder 1, and can stably and quickly suppress the magnitude of the positive deviation of a given system process. Taking a thermal power unit as an example, it takes a certain amount of time for the superheated steam temperature to go from zero deviation to a certain positive deviation; this is the lag in the one-position control method. The integrator 20 has an accelerating effect in the positive feedback loop (first adder 1). The acceleration effect begins after the superheated steam temperature starts from zero deviation, without any lag problem. Therefore, it has a good effect on suppressing the positive overheating of the superheated steam temperature control system. Because the integrator 20 incorporates an integrator limiter controller 21, the problem of non-convergence of the integrator 20 output in the positive feedback loop is avoided.
[0025] For example, the positive output controller 4 is used to extract the positive signal from the output signal of the differentiator 3 and output it to the first input terminal of the second adder 5.
[0026] For example, the differentiator 3 is used to extract the differential signal from the acceleration signal.
[0027] For example, the second addition step 5 is used to add the positive signal to the external process signal and output the external process signal after superimposing the positive signal through the output terminal.
[0028] For example, the transfer function of the integrator limiting controller is: ,in, I ( t ) is the output signal of integrator 20. PV IN ( t ) represents the external process signal. s For the Laplace operator, T I is the integration time constant.
[0029] For example, the transfer function of the positive output controller 4 is: , in, FOC ( t ) is the output signal of the positive output controller 4. D ( t ) is the output signal of differentiator 3.
[0030] For example, the transfer function of the differentiator 3 is: , in,D ( s Let ) be the transfer function of differentiator 3. s For the Laplace operator, T D is the differential time constant.
[0031] For example, the transfer function of the integrator 20 is: , in, I ( s Let s be the transfer function of integrator 20, and s be the Laplace operator. T I is the integration time constant.
[0032] In one embodiment, PFAO is used to accelerate the observation of the output signal of a fourth-order inertia process (FOIP) with a unit step input.
[0033] The fourth-order inertial process FOIP is: ; In the formula, FOIP ( s () is the transfer function of the fourth-order inertial process FOIP. s For the Laplace operator, T FOIP FOIP time constant, in seconds.
[0034] exist T I =100s, T D =100s, T FOIP =100s, the FOIP input is a unit step signal, and the experimental results of the forward acceleration observer output signal of the FOIP process are obtained, such as... Figure 2 As shown.
[0035] PV FOIP(t) The output signal of the FOIP (Forward Inertial Programming) process under a unit step input is a fourth-order inertial process. PV PFAO(t) This is the process output signal of the process forward acceleration observer PFAO.
[0036] It is evident that the process output signal of PFAO significantly leads the process output signal of FOIP.
[0037] In other words, the positive acceleration observer plays a positive lead role, which can advance the positive control quantity and has a good effect on suppressing the positive overheating of the superheated steam temperature control system.
[0038] Please see Figure 3 One embodiment of this application provides a controller for a process-oriented positive acceleration system, applied to the aforementioned multiple error calculation units, including: a cascaded proportional controller, an engineering fastest integrator, a third addition stage, a process-oriented positive acceleration device as described in the above device embodiment, and a negative proportional stage.
[0039] The input terminal of the cascade proportional controller receives the deviation signal between the process input and the process output. The output terminal of the cascade proportional controller is connected to the input terminal of the fastest integrator and the input terminal of the process-oriented positive acceleration device. The output terminal of the fastest integrator is connected to the first input terminal of the third adder. The second input terminal of the third adder is connected to the output terminal of the process-oriented positive acceleration device, and the output terminal of the third adder is connected to the input terminal of the negative proportional element.
[0040] The negative proportional element is used to output a control signal to the control process, and the process output is obtained at the output end of the control process.
[0041] Figure 3 The given controller (C) is: ; In the formula, C ( s ) is the transfer function of controller C. PFAO ( s ) is the transfer function of the process forward acceleration observer PFAO. EFI ( s ) is the transfer function of the Engineering Fastest Integrator (EFI). s For the Laplace operator, K CPC This represents the gain of the cascade proportional controller (CPC), expressed in dimensionless units; in the EFI transfer function, n Let z be the total order of EFI, i be the i-th order, and the unit be dimensionless. T EFI Here, represents the time constant of HEI, in seconds; in the transfer function of PFAO, I ( t () is the output signal of the integrator. PV IN ( t ) is the input signal of PFAO. T IThe integral time constant is in seconds. T D is the differential time constant, with the unit being seconds.
[0042] Specifically, when the controller C is connected to the superheated steam temperature control system of a 1000 MW supercritical thermal power unit in a power plant, the control results are as follows: Figure 4 As shown.
[0043] Figure 4 As shown, after 12:00, the process positive acceleration observer (PFAO) was added. Before adding PFAO, the maximum positive deviation of the superheated steam temperature relative to the given superheated steam temperature was 12.9℃. After adding PFAO, the maximum positive deviation of the superheated steam temperature was 7.9℃. It can be seen that PFAO has a good effect on suppressing the positive deviation of the superheated steam temperature.
[0044] Compared to existing technologies, the controller for a process-oriented forward acceleration system provided in this embodiment of the invention addresses the hysteresis problem caused by process signal deviations. It utilizes a first adder 1 to add the integrated external process signal to the external process signal, advancing the positive control input and accelerating the external process signal. A positive output controller 4 filters out negative signals, ensuring the positive direction of the superimposed signal in the second adder 5. The first adder 1 and the positive output controller 4 work together to perform limited positive and lead processing on the process signal, accelerating the formation of a positive deviation in a given process. Furthermore, an integrator limiting controller limits the integrator output, ensuring its convergence.
[0045] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.
Claims
1. A process-oriented forward acceleration device, characterized in that, It includes a first adding stage, a limiting integrator, a differentiator, a positive output controller, and a second adding stage; the limiting integrator includes an integrator and an integrator limiting controller; the integrator limiting controller is used to limit the output of the integrator; The first input terminal of the first adder is used to receive external process signals; the second input terminal of the first adder is connected to the output terminal of the integrator; the output terminal of the first adder is connected to the input terminal of the integrator and the input terminal of the differentiator; the output terminal of the differentiator is connected to the input terminal of the positive output controller; the output terminal of the positive output controller is connected to the first input terminal of the second adder; the second input terminal of the second adder is used to receive external process signals; the output terminal of the second adder is used to output the external process signal superimposed with the positive signal. The first addition stage is used to add the output signal of the integrator and the external process signal to accelerate the external process signal and output an acceleration signal to the differentiator.
2. The process-oriented forward acceleration device as described in claim 1, characterized in that, The positive output controller is used to extract the positive signal from the output signal of the differentiator and output it to the first input terminal of the second adder.
3. The process-oriented forward acceleration device as described in claim 1, characterized in that, The differentiator is used to extract the differential signal from the acceleration signal.
4. The process-oriented forward acceleration device as described in claim 1, characterized in that, The second addition step is used to add the positive signal to the external process signal and output the external process signal after superimposing the positive signal through the output terminal.
5. The process-oriented forward acceleration device as described in claim 1, characterized in that, The transfer function of the integrator limiting controller is: ,in, I ( t () is the output signal of the integrator. PV IN ( t ) represents the external process signal. s For the Laplace operator, T I is the integration time constant.
6. The process-oriented forward acceleration device as described in claim 1, characterized in that, The transfer function of the positive output controller is: ， in, FOC ( t ) is the output signal of the positive output controller. D ( t ) is the output signal of the differentiator.
7. The process-oriented forward acceleration device as described in claim 1, characterized in that, The transfer function of the differentiator is: ， in, D ( s Let be the transfer function of the differentiator. s For the Laplace operator, T D is the differential time constant.
8. The process-oriented forward acceleration device as described in claim 1, characterized in that, The transfer function of the integrator is: ， in, I ( s Let be the transfer function of the integrator, and s be the Laplace operator. T I is the integration time constant.
9. A process-oriented forward acceleration system controller, characterized in that, It includes a cascaded proportional controller, a fastest integrator, a third adding stage, a process-oriented positive acceleration device as described in any one of claims 1-8, and a negative proportional stage; The input terminal of the cascade proportional controller receives the deviation signal between the process input and the process output. The output terminal of the cascade proportional controller is connected to the input terminal of the fastest integrator and the input terminal of the process-oriented forward acceleration device. The output terminal of the fastest integrator is connected to the first input terminal of the third addition stage. The second input terminal of the third addition stage is connected to the output terminal of the process-oriented positive acceleration device, and the output terminal of the third addition stage is connected to the input terminal of the negative proportional stage. The negative proportional element is used to output a control signal to the control process, and the process output is obtained at the output end of the control process.