Continuous variable load amplitude identification control method, system and equipment in AGC mode of thermal power generating unit and storage medium

Abstract

The invention discloses a thermal power generating unit continuous variable load amplitude identification control method, system and device in an AGC mode and a storage medium, and the method comprises the following steps: obtaining unit operation parameters, and judging the variable load direction and variable load amplitude of a current unit according to the unit operation parameters; calculating the variable load equivalent amplitude of the current unit in real time according to the thermal inertia of the boiler system and the unit parameters in the AGC mode; according to the method, operating parameters in the unit load changing process are analyzed, working condition data influencing unit control are recorded, and a corresponding control strategy is added in an identification control method according to analysis and calculation of the working condition data. According to the method, accurate variable load amplitude and shape feedforward can be provided in the variable load process of the unit in the AGC mode, and the change trend of parameters such as the steam temperature and the steam pressure of the unit is estimated, so that the accuracy of steam temperature adjustment, steam pressure adjustment and load adjustment of the unit in a predictive control strategy is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of unit control strategies, and in particular to a method, system, device and storage medium for continuously variable load amplitude identification control in an AGC mode of a thermal power unit. Background Art

[0002] The AGC instructions that the power grid gives to each unit are discrete instructions, and the amplitude difference between two AGC instructions is usually within 1-5%Pe. When the power grid requires the unit to change load significantly, the AGC instructions issued are usually divided into several small-amplitude load change instructions and continuously issued to the unit. For example, if the power grid plans to adjust the load of the unit by 10%, the unit's AGC instruction will first send a unit instruction with an interval amplitude of 3%Pe. When the actual load of the unit reaches the AGC instruction dead zone, the dispatcher will send another unit AGC instruction with an interval amplitude of 3%Pe, and so on, and finally reach the target load value. The interval time of each AGC instruction is at least 1 minute. Therefore, it is necessary to identify these discrete AGC instructions in order to better and more smoothly predict and control the unit.

[0003] The load variation amplitude of the traditional control strategy is the unit target load command minus the unit actual load command; the disadvantage of this calculation method is that during the load variation process, the load variation amplitude value will gradually decrease as the unit actual load command approaches the target load command, until the load variation is completed, and the load variation amplitude also becomes "0" at the same time; another shortcoming is that the impact of the unit operating conditions before the load variation on the current load variation cannot be taken into account, so it has great limitations in actual application. Summary of the invention

[0004] The purpose of the present invention is to provide a method, system, device and storage medium for continuously variable load amplitude identification control in AGC mode of a thermal power unit, optimize the traditional control strategy, and solve the deficiency that the previous control strategy can only analyze and calculate a single instruction.

[0005] To achieve the above purpose, the technical solution provided by the present invention is:

[0006] The first aspect of the present application provides a method for continuously variable load amplitude identification and control in an AGC mode of a thermal power unit, characterized in that it comprises the following steps:

[0007] Obtain the unit operating parameters, and determine the load change direction and load change amplitude of the current unit according to the unit operating parameters;

[0008] Calculate the current unit load equivalent amplitude in real time based on the thermal inertia of the boiler system and the parameters in AGC mode;

[0009] By analyzing the operation of the unit under variable load, the operating data that affects the unit control is recorded, and the control strategy is added to the identification control method based on the analysis and calculation of the operating data.

[0010] To optimize the above technical solutions, the specific measures taken also include:

[0011] The parameters in the AGC mode include the size and interval time of the two most recent AGC instructions and the unit load change rate.

[0012] The operation analysis of the unit in variable load includes analysis and identification of the unit's operating conditions, as well as reference to the reference load latch and the unit's inertia rate setting.

[0013] The control strategy added to the identification control method based on the analysis and calculation of the operating condition data is that when the unit changes load, the current actual load instruction of the unit is latched as the reference value for the load change amplitude of the computer unit, and the latching time, release rate and timing of the latched reference load value are determined based on the collected parameter analysis, thereby adding the control strategy.

[0014] Furthermore, if the directions of two consecutive load changes are the same, after the previous load change is completed, if the new AGC instruction has not been received, the unit load change latch value will be slowly released according to the operating characteristics of the unit; when the next load change instruction arrives, if the previous load change latch value has not been released, the current load change latch value will be latched again; the current unit load change amplitude is accumulated as the equivalent load change amplitude of this load change; if the load change latch value is already equal to the current actual load instruction, then when a new load instruction arrives, the current unit actual load instruction will be re-latched as the new load change amplitude calculation reference value.

[0015] Furthermore, if the direction of the load change changes, when the load change instruction arrives, the previous load change latch value is quickly released, and the current actual load instruction is re-locked when the new AGC instruction arrives as the initial load change latch value; the amplitude of this load change is used as the load change amplitude during the current load change period, and the subsequent load change amplitude calculation uses the load change latch value latched this time as the reference value.

[0016] Furthermore, when no new AGC instruction arrives within a set time after the load change is completed, the unit target load instruction is changed, and the unit load change latch value is released as the unit's current actual load instruction.

[0017] The second aspect of the present application provides a continuously variable load amplitude identification control system in an AGC mode of a thermal power unit, comprising:

[0018] The unit operation parameter acquisition module is used to obtain the unit operation parameters and determine the load change direction and load change amplitude of the current unit according to the unit operation parameters;

[0019] The variable load equivalent amplitude calculation module is used to calculate the current unit variable load equivalent amplitude in real time according to the thermal inertia of the boiler system and the parameters in the AGC mode;

[0020] The identification control module is used to record the operating data that affects the control of the unit through the operation analysis of the unit under variable load, and add control strategies to the identification control method based on the analysis and calculation of the operating data.

[0021] The continuously variable load amplitude identification control system under the AGC mode of the thermal power unit is used to execute the continuously variable load amplitude identification control method under the AGC mode of the thermal power unit as described above.

[0022] The third aspect of the present application provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the continuous variable load amplitude identification control method under the AGC mode of a thermal power unit as described above is implemented.

[0023] A fourth aspect of the present application provides a computer-readable storage medium storing a computer program, wherein the computer program enables a computer to execute the continuous variable load amplitude identification control method under the AGC mode of a thermal power unit as described above.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] When the unit is running in AGC mode, variable loads of different amplitudes have different effects on the unit's steam pressure and steam temperature. In order to better control parameters such as the unit's steam pressure and steam temperature, feedforwards of different sizes and shapes are required. The present invention records the data of multiple previous operating conditions that have an impact on the unit's control, and performs analysis and calculation through methods such as unit operation data collection, operating condition analysis and identification, reference reference load latching, and unit inertia rate setting, thereby solving the problem that previous control strategies can only analyze and calculate a single instruction.

[0026] The present invention can ensure that the unit can provide accurate load variation amplitude and shape feedforward during load variation in AGC mode, and estimate the variation trend of parameters such as the unit's steam temperature and steam pressure, so as to ensure the accuracy of the unit's steam temperature regulation, steam pressure regulation, and load regulation in the predictive control strategy. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 : A flow chart of a method for continuously variable load amplitude identification and control in the AGC mode of a thermal power unit according to the present invention.

[0028] Figure 2 : Schematic diagram of the structure of the continuously variable load amplitude identification control method and system under AGC mode.

[0029] Figure 3 : Single direction continuous variable load curve of Example 1.

[0030] Figure 4 : Single-direction discontinuous AGC instruction variable load curve of Example 2.

[0031] Figure 5 : Irregular AGC instruction variable load curve of Example 3. DETAILED DESCRIPTION

[0032] The above contents of the present invention are further described in detail below in the form of embodiments, but this should not be understood as the scope of the above subject matter of the present invention being limited to the following embodiments, and all technologies realized based on the above contents of the present invention belong to the scope of the present invention.

[0033] In one embodiment of the present invention, a method for continuously variable load amplitude identification control in AGC mode of a thermal power unit is proposed. Figure 1 As shown, the following steps are included:

[0034] Obtain the unit operating parameters, and determine the load change direction and load change amplitude of the current unit according to the unit operating parameters;

[0035] Calculate the current unit load equivalent amplitude in real time based on the thermal inertia of the boiler system and the parameters in AGC mode;

[0036] By analyzing the operation of the unit under variable load, the operating data that affects the unit control is recorded, and the control strategy is added to the identification control method based on the analysis and calculation of the operating data.

[0037] The parameters in AGC mode include the size and interval time of the two most recent AGC instructions and the unit load change rate.

[0038] The operation analysis of the unit under variable load includes the analysis and identification of the unit's operating conditions, as well as the reference to the reference load latch and the unit's inertia rate setting.

[0039] Based on the analysis and calculation of the operating condition data, a control strategy is added to the identification control method. When the unit changes load, the current actual load instruction of the unit is latched as the reference value for the load change amplitude of the computer unit. The latching time, release rate and timing of the latched reference load value are determined based on the collected parameter analysis, thereby adding a control strategy.

[0040] In some embodiments, if the directions of two consecutive load changes are the same, after the previous load change ends, if the new AGC instruction has not been received, the unit load change latch value is slowly released according to the operating characteristics of the unit; when the next load change instruction arrives, if the previous load change latch value has not been released, the current load change latch value is latched again; the current unit load change amplitude is accumulated as the equivalent load change amplitude of this load change; if the load change latch value is already equal to the current actual load instruction, then when a new load instruction arrives, the current unit actual load instruction is re-latched as the new load change amplitude calculation reference value.

[0041] In some embodiments, if the direction of the load change changes, when the load change instruction arrives, the previous load change latch value is quickly released, and the current actual load instruction is re-locked when the new AGC instruction arrives as the initial load change latch value; the amplitude of this load change is used as the load change amplitude during the current load change period, and the subsequent load change amplitude calculation uses the load change latch value latched this time as the reference value.

[0042] In some implementations, when no new AGC instruction arrives within a set time after the load change is completed, the unit target load instruction is changed, and the unit load change latch value is released as the unit's current actual load instruction.

[0043] The specific variable load equivalent amplitude calculation control method is as follows: Figure 2 shown.

[0044] In another embodiment, the present invention proposes a continuously variable load amplitude identification control system in an AGC mode of a thermal power unit, comprising:

[0045] The unit operation parameter acquisition module is used to obtain the unit operation parameters and determine the load change direction and load change amplitude of the current unit according to the unit operation parameters;

[0046] The variable load equivalent amplitude calculation module is used to calculate the current unit variable load equivalent amplitude in real time according to the thermal inertia of the boiler system and the parameters in the AGC mode;

[0047] The identification control module is used to record the operating data that affects the control of the unit through the operation analysis of the unit under variable load, and add control strategies to the identification control method based on the analysis and calculation of the operating data.

[0048] The continuously variable load amplitude identification control system under the AGC mode of a thermal power unit is used to execute the above continuously variable load amplitude identification control method under the AGC mode of a thermal power unit.

[0049] The present invention is further described in detail below in conjunction with specific embodiments:

[0050] In order to better illustrate the control effect of the identification system of the present invention, the equivalent amplitude of unit variable load calculated by the method of the instruction identification system under several different common AGC instruction types of grid-related units is compared with the calculation results of the traditional control method, and its superiority is shown through difference comparison.

[0051] Example 1 Equivalent identification of continuous small load instructions in one direction

[0052] This type of working condition is divided into two types: one-way continuous load increase and one-way continuous load reduction. It usually occurs when the dispatcher needs to adjust the unit load over a large range. The specific working conditions are as follows: Figure 3 shown.

[0053] Figure 3 The example shown is a single-direction continuous load change, where the time period from T0 to T4 is a single-direction load increase stage, and the time period from T6 to T9 is a single-direction load reduction stage; assuming that the unit load change amplitude is a variable P, the traditional unit load change amplitude is in the T1-T2 section load change amplitude P = MW1-MW_S; T2-T3 section load change amplitude P = MW2-MW1; T3-T4 section load change amplitude P = MW3-MW2; T6-T7 section load change amplitude P = MW5-MW5_S; T7-T8 section load change amplitude P = MW6-MW5; T8-T9 section load change amplitude P = MW7-MW6; Figure 3 The actual operation analysis of the units shown is as follows: Figure 3 In the load variation process of the T1-T4 time period shown, the actual load variation amplitude of the unit is consistent with the unit AGC instruction directly changing from MW_S to MW3 operating condition at the T1 time point; in the load variation process of the T6-T9 time period, the actual load variation amplitude of the unit is consistent with the unit AGC instruction directly changing from MW5_S to MW7 operating condition at the T6 time point; but the traditional control strategy cannot identify such differences in operating conditions.

[0054] The instruction identification control strategy of this embodiment calculates the variable load amplitude P for this type of working condition as follows: during the unidirectional load increase process in the T0-T4 time period, in the T1-T2 time period, the variable load amplitude P=MW1-MW_S; in the T2-T3 time period, the variable load amplitude P=MW2-MW_S; in the T3-T4 time period, the variable load amplitude P=MW3-MW_S; each time a new AGC instruction is received, the variable load amplitude is gradually accumulated according to the actual working conditions.

[0055] During the continuous load reduction process in the T6-T9 time period, in the T6-T7 time period, the variable load amplitude P = MW5-MW5_S; in the T7-T8 time period, the variable load amplitude P = MW6-MW5_S; in the T8-T9 time period, the variable load amplitude P = MW7-MW5_S; during the entire load reduction process, the absolute value of the load reduction amplitude P also gradually increases according to the reduction of the unit's target load instruction.

[0056] Example 2: Equivalent identification of one-way discontinuous small load instructions

[0057] Figure 4 This is an example of a single-direction discontinuous AGC instruction variable load curve, where Figure 3 The main difference between the working conditions is that when the load is changed, the AGC instruction does not immediately increase or decrease the load instruction, and a new AGC instruction is issued after a period of time. This working condition is different from the variable load amplitude calculation logic of the traditional control strategy. Figure 3 The calculation method is the same as in , and will not be repeated here.

[0058] The equivalent variable load amplitude load calculation result in the command identification control logic designed in this embodiment 2 is as follows: T1-T2 time period, variable load amplitude P = MW1-MW_S; when reaching T2 time point, the actual load command MW2' has reached the AGC load command MW1, but the new AGC command has not arrived. At this time, it is necessary to slowly increase the variable load initial latch value MW_S (the rate is adjusted according to the unit characteristics) from MW_S to MW1 until it is latched again when the new AGC command arrives; Figure 4 At time point T3, the new AGC instruction changes from MW1 to MW3 at time point T3, and the latched variable load reference value is MW3_S. Therefore, in this variable load process, the unit equivalent variable load amplitude P = MW3-MW3_S; at time point T4, the unit actual load instruction reaches AGC instruction MW3, the variable load ends, and the unit variable load initial latch value begins to change to MW3 again; at time point T8, the AGC instruction does not change, and the variable load initial value MW_S' = MW3 at time point T8, and the initial load latch is released; at time node T11, when the AGC instruction changes to MW4, the variable load amplitude is recalculated, and in the T11-T12 time period, the variable load amplitude P = MW4-MW4_S; at time point T12, the load change ends, and the unit variable load latch value MW4_S is released again, slowly changing to MW4. The change trend is shown in the MW5_S curve of the T12-T13 time period.

[0059] At time point T13, a new AGC instruction arrives. Since this AGC instruction is changing in the direction of reducing load, the previous load instructions have always been in the direction of increasing load; therefore, in the process of T13-T14, the equivalent variable load amplitude P=MW5-MW5', instead of P=MW5-MW5_S; at the moment when the AGC instruction MW5 arrives, the program directly changes the initial load latch value of the variable load from MW5_S to MW7_S, and the new actual variable load amplitude is used as the variable load amplitude of the T13-T14 time period; in the T14-T15 time period, the variable load amplitude P=MW6-MW7_S (MW7_S=MW5'); at the T15 time node, the actual load of the unit reaches MW6, and the initial value of the variable load changes slowly from MW7_S to MW6; when it reaches the T18 node, the initial value of the unit variable load changes from MW7_S to MW8_S, so in the T18-T19 time period, the variable load amplitude P=MW8-MW8_S.

[0060] Example 3 Irregular AGC instruction equivalent identification

[0061] Figure 5 It is an irregular AGC instruction variable load curve. When the unit is in normal operation mode and there is no large-scale power generation or load change on the power grid, the dispatching energy management platform slightly adjusts the operating curve of the grid-related unit load in order to stabilize the frequency and flow.

[0062] Under the new control strategy, in the T1-T2 time period, the unit equivalent variable load amplitude P = MW1-MW_S, and in the T2-T3 time period, the unit equivalent variable load amplitude P = MW2-MW_S; at other time points, due to the change in the direction of the variable load, from increasing load to reducing load, the variable load starting load also changes at the same time, from MW_S to MW3_S; therefore, in the T3-T4 time period, the unit variable load amplitude P = MW3-MW3_S; at the T4 time point, due to the change in the unit load direction again, from reducing load to increasing load process, the variable load initial latch value changes from MW3_S to MW4_S, and in the T4-T5 time period, the unit variable load amplitude P = MW4-MW4_S.

[0063] At time point T5, the unit load change is not completed, and the AGC instruction becomes smaller again, from MW4 to MW5. The unit also changes from the load increase process to the load reduction process; the unit load change initial latch value changes from MW4_S to MW5_S (note: at this time, the load change initial latch value MW5_S≠MW4, but is equal to the actual load instruction MW5'); in the T5-T6 time period, before the unit load change process is completed, the unit load change equivalent value P=MW5-MW5_S. After the unit load change is completed, the load change initial latch value will gradually decrease. At time point T6, the unit load change initial latch value has gradually changed from MW5_S to MW6_S. The change trajectory is as follows Figure 5 As shown in the curve; therefore, in the T6-T7 time period, the unit equivalent variable load amplitude P = MW6-MW6_S; at the T7 load point, the variable load direction changes again, from a load reduction process to a load increase process; the variable load initial latch value changes instantaneously from MW6_S to MW7_S, and in the T7-T8 time period, the variable load amplitude equivalent value P = MW7-MW7_S.

[0064] In another embodiment of the present invention, an electronic device is proposed, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the above-mentioned method for continuously variable load amplitude identification and control in the AGC mode of a thermal power unit is implemented.

[0065] In another embodiment, the present invention provides a computer-readable storage medium storing a computer program, wherein the computer program enables a computer to execute the above-mentioned continuous variable load amplitude identification control method in the AGC mode of a thermal power unit.

[0066] In the embodiments disclosed in the present application, the computer storage medium can be a tangible medium that can contain or store a program for use by or in conjunction with an instruction execution system, device or equipment. The computer storage medium can include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or equipment, or any suitable combination of the above. More specific examples of computer storage media can include electrical connections based on one or more lines, portable computer disks, hard disks, random access memories (RAM), read-only memories (ROM), erasable programmable read-only memories (EPROM or flash memory), optical fibers, portable compact disk read-only memories (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the above.

[0067] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any technician familiar with the profession, without departing from the scope of the technical solution of the present invention, according to the technical essence of the present invention, any simple modification, equivalent replacement and improvement made to the above embodiment still falls within the protection scope of the technical solution of the present invention.

Claims

1. A method for continuously variable load amplitude identification and control in AGC mode of a thermal power unit, characterized in that: The following steps are involved: Obtain the unit operating parameters, and determine the load change direction and load change amplitude of the current unit according to the unit operating parameters; Calculate the current unit load equivalent amplitude in real time based on the thermal inertia of the boiler system and the parameters in AGC mode; By analyzing the operation of the unit during load variation, the operating data that affect the unit control are recorded, and control strategies are added to the identification control method based on the analysis and calculation of the operating data.

2. The method for continuously variable load amplitude identification and control in AGC mode of a thermal power plant according to claim 1, characterized in that: The parameters in the AGC mode include the size and interval time of the two most recent AGC instructions and the unit load change rate.

3. The method for continuously variable load amplitude identification and control in AGC mode of a thermal power plant according to claim 1, characterized in that: The operation analysis of the unit during load variation includes analysis and identification of the unit's operating conditions, as well as reference to the reference load latch and the unit's inertia rate setting.

4. The method for continuously variable load amplitude identification and control in AGC mode of a thermal power plant according to claim 1, characterized in that: The control strategy added to the identification control method based on the analysis and calculation of the operating condition data is that when the unit changes load, the current actual load instruction of the unit is latched as the reference value for the load change amplitude of the computer unit, and the latching time, release rate and timing of the latched reference load value are determined based on the collected parameter analysis, thereby adding the control strategy.

5. The method for continuously variable load amplitude identification and control in AGC mode of a thermal power plant according to claim 4, characterized in that: If the direction of two consecutive load changes is the same, after the previous load change is completed, if the new AGC instruction has not been received, the unit load change latch value will be slowly released according to the unit's operating characteristics; when the next load change instruction arrives, if the previous load change latch value has not been released, the current load change latch value will be latched again; the current unit load change amplitude is accumulated as the equivalent load change amplitude of this load change; If the variable load latch value is already equal to the current actual load instruction, then when a new load instruction arrives, the current unit actual load instruction is re-latched as a new variable load amplitude calculation reference value.

6. The method for continuously variable load amplitude identification and control in AGC mode of a thermal power plant according to claim 4, characterized in that: If the load change direction changes, when the load change instruction arrives, the previous load change latch value is quickly released, and the current actual load instruction is re-locked as the initial load change latch value when the new AGC instruction arrives; The amplitude of this load change is used as the load change amplitude during the current load change period, and the subsequent load change amplitude calculation uses the load change latch value latched this time as the reference value.

7. The method for continuously variable load amplitude identification and control in AGC mode of a thermal power plant according to claim 4, characterized in that: When no new AGC instruction arrives within the set time after the load change is completed, the unit target load instruction is changed, and the unit load change latch value is released as the unit's current actual load instruction.

8. A continuously variable load amplitude identification control system in AGC mode of a thermal power unit, characterized in that: include: The unit operation parameter acquisition module is used to obtain the unit operation parameters and determine the load change direction and load change amplitude of the current unit according to the unit operation parameters; The variable load equivalent amplitude calculation module is used to calculate the current unit variable load equivalent amplitude in real time according to the thermal inertia of the boiler system and the parameters in the AGC mode; The identification control module is used to record the operating data that affects the control of the unit through the operation analysis of the unit under variable load, and add control strategies to the identification control method based on the analysis and calculation of the operating data. The continuously variable load amplitude identification control system in the AGC mode of a thermal power plant is used to execute the continuously variable load amplitude identification control method in the AGC mode of a thermal power plant according to any one of claims 1 to 7.

9. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the method for continuously variable load amplitude identification and control in the AGC mode of a thermal power unit as described in any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium storing a computer program, wherein the computer program enables a computer to execute the method for continuously variable load amplitude identification and control in AGC mode of a thermal power unit according to any one of claims 1 to 7.

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