A load-stage coal quality correction coefficient control method and device

Abstract

An embodiment of the present invention provides a load-segmented coal quality correction coefficient control method, comprising: sampling the operating parameters of a unit to obtain corresponding sampling values, and determining the unit's stable state, load measurement values ​​of the load, and coal quantity measurement values ​​based on the sampling values; when the unit's stable state is stable, determining the coal quality correction coefficient based on the load measurement value and the coal quantity measurement value, and using the determined coal quality correction coefficient as a primary coal quality correction coefficient; determining the current load segment in which the load sampling value is located from preset N load segments; when the unit's stable state is stable, using the primary coal quality correction coefficient to update the coal quality correction coefficient corresponding to the current load segment, and maintaining the coal quality correction coefficients corresponding to other load segments in the N load segments except the current load segment; when the unit's stable state is unstable, maintaining the coal quality correction coefficients corresponding to all load segments; reading the coal quality correction coefficient corresponding to the current load segment and outputting it as the current coal quality correction coefficient.

Description

Technical Field

[0001] The present invention relates to the field of thermal power generation automatic control, and in particular to a load-segmented coal quality correction coefficient control method and device. Background Art

[0002] Existing coal quality correction technologies mostly use BTU (British Thermal Unit) coefficient correction. The method is to calculate the deviation between the unit's real-time coal quantity and the reference coal quantity, and use a PID controller to perform calculations. The output result is the BTU coefficient.

[0003] In the process of implementing the present invention, the applicant discovered that the prior art has at least the following problems:

[0004] The existing technology takes a long time to adjust the coal quality correction coefficient when the coal quality changes and cannot adapt to changes in the number of coal mills. When the coal quality remains unchanged and the load changes, the coal quality correction coefficient is adjusted incorrectly. Summary of the Invention

[0005] The embodiments of the present invention provide a load-segmented coal quality correction coefficient control method and device, which solve the problems in the prior art where the coal quality correction coefficient takes a long time to adjust when the coal quality changes and cannot adapt to changes in the number of coal mills, and the coal quality correction coefficient is incorrectly adjusted when the load changes while the coal quality remains unchanged.

[0006] To achieve the above objectives, on the one hand, an embodiment of the present invention provides a load-staged coal quality correction coefficient control method, comprising:

[0007] Sampling the operating parameters of the unit to obtain sampling values ​​of the operating parameters, and determining the unit steady state, a load measurement value of the load, and a coal quantity measurement value of the coal quantity according to the sampling values ​​of the operating parameters;

[0008] When the unit is in a stable state, determining a coal quality correction coefficient according to the load measurement value and the coal quantity measurement value, and using the determined coal quality correction coefficient as a primary coal quality correction coefficient;

[0009] Determining a current load segment in which the sampled value of the load is located from among the preset N load segments;

[0010] When the unit is in a stable state, the coal quality correction coefficient corresponding to the current load segment is updated using the primary coal quality correction coefficient, and the coal quality correction coefficients corresponding to the other load segments among the N load segments except the current load segment are maintained; when the unit is in an unstable state, the coal quality correction coefficients corresponding to all load segments are maintained;

[0011] Reading the coal quality correction coefficient corresponding to the current load segment and outputting it as the current coal quality correction coefficient;

[0012] The operating parameters include load and coal quantity; the N load segments do not overlap with each other; and N is a positive integer greater than or equal to 1.

[0013] On the other hand, an embodiment of the present invention provides a load-staged coal quality correction coefficient control device, comprising:

[0014] The unit stability judgment and operating parameter measurement unit is used to sample the operating parameters of the unit to obtain sampling values ​​of the operating parameters, and determine the unit stability state, load measurement value and coal quantity measurement value based on the sampling values ​​of the operating parameters;

[0015] a primary coal quality correction coefficient determination unit, configured to determine a coal quality correction coefficient according to the load measurement value and the coal quantity measurement value when the unit is in a stable state, and use the determined coal quality correction coefficient as the primary coal quality correction coefficient;

[0016] A load segment determination unit, configured to determine a current load segment in which the load sampling value is located from among N preset load segments;

[0017] a load segment coal quality correction coefficient updating unit, configured to update the coal quality correction coefficient corresponding to the current load segment using the primary coal quality correction coefficient when the unit is in a stable state, and to maintain the coal quality correction coefficients corresponding to the other load segments among the N load segments except the current load segment; and to maintain the coal quality correction coefficients corresponding to all load segments when the unit is in an unstable state;

[0018] a current coal quality correction coefficient output unit, configured to read the coal quality correction coefficient corresponding to the current load segment and output it as the current coal quality correction coefficient;

[0019] The operating parameters include load and coal quantity; the N load segments do not overlap with each other; and N is a positive integer greater than or equal to 1.

[0020] The above technical solution has the following beneficial effects: Whether the unit is in steady state is determined based on the unit load, coal quantity, and main steam pressure. The steady-state coal quality correction coefficient is then calculated. Finally, the coal quality correction coefficient for each load segment is derived based on the load segment. The coal quality correction coefficients derived for each load segment are more closely aligned with actual operating conditions, ensuring that the unit has separate coal quality coefficients for each load segment. This eliminates the need for a PID control module, enabling faster coal quantity adjustments when coal quality changes, and ensuring economical operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 This is a flow chart of a load-stage coal quality correction coefficient control method according to one embodiment of the present invention;

[0023] Figure 2 This is an architectural diagram of a load-stage coal quality correction coefficient control device according to one embodiment of the present invention;

[0024] Figure 3 It is a part of the circuit principle diagram of a load-stage coal quality correction coefficient control device according to one embodiment of the present invention;

[0025] Figure 4 This is another part of the circuit schematic diagram of a load-stage coal quality correction coefficient control device according to one embodiment of the present invention;

[0026] Figure 5 This is another part of the circuit schematic diagram of a load-stage coal quality correction coefficient control device according to one embodiment of the present invention;

[0027] The reference numerals indicate:

[0028] 111: First lead-lag module; 112: Second lead-lag module; 113: First three-value selection module; 114: First NOT gate; 121: Third lead-lag module; 122: Fourth lead-lag module; 123: Second three-value selection module; 124: Second NOT gate; 131: First over-limit alarm module; 132: First OR gate; 133: Third NOT gate; 141: First AND gate; 143: First delay-on module; 144: Second delay-on module; 142: Second AND gate; 21: First divider; 23: First selection module; 24: The second selection module; 151: the third delayed opening module; 152: the fourth NOT gate; 31: the comparison module corresponding to the boundary value of the load segment in the load segment determination unit; 32: the NOT gate corresponding to the load segment in the load segment determination unit; 33: the AND gate corresponding to the load segment in the load segment determination unit; 42: the AND gate corresponding to the load segment in the load segment coal quality correction coefficient update unit; 41: the follower corresponding to the load segment in the load segment coal quality correction coefficient update unit; 51: the selection module corresponding to the load segment in the current coal quality correction coefficient output unit; 52: the adder. DETAILED DESCRIPTION

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0030] The inventors have used the method of adjusting the coal quality correction coefficient based on the PID controller in the prior art for a long time and analyzed the problems encountered during use. They found that the prior art has the following problems:

[0031] The first is excessively long adjustment time. Existing PID integration times are often long, typically exceeding 3,600 seconds. This results in very slow BTU coefficient correction when coal quality changes. It takes approximately two hours in a steady-state environment to fully adjust the BTU coefficient, which cannot meet the needs of frequently changing loads and coal quality.

[0032] Second, there's a lack of logic for determining steady-state conditions. When the unit's load changes without changing coal quality, deviations between the real-time and baseline coal quantities can occur. Existing solutions also alter the BTU coefficient, leading to misregulation.

[0033] Third, the BTU coefficient is not segmented by load. In actual operation, the number of coal mills started at different load levels varies. Often, the coal quality of the same coal mill is the same, but different coal mills have different coal qualities, so the coal quality will change as the load enters different ranges.

[0034] In order to solve the above problems, on the one hand, Figure 1 As shown, an embodiment of the present invention provides a load-staged coal quality correction coefficient control method, comprising:

[0035] Step S600: sampling the operating parameters of the unit to obtain sampled values ​​of the operating parameters, and determining the unit's stable state, a load measurement value, and a coal quantity measurement value based on the sampled values ​​of the operating parameters;

[0036] Step S601, when the unit is in a stable state, determining a coal quality correction coefficient according to the load measurement value and the coal quantity measurement value, and using the determined coal quality correction coefficient as a primary coal quality correction coefficient;

[0037] Step S602, determining the current load segment where the load sampling value is located from the preset N load segments;

[0038] Step S603: When the unit is in a stable state, the coal quality correction coefficient corresponding to the current load segment is updated using the primary coal quality correction coefficient, and the coal quality correction coefficients corresponding to the other load segments among the N load segments except the current load segment are maintained; when the unit is in an unstable state, the coal quality correction coefficients corresponding to all load segments are maintained;

[0039] Step S604, reading the coal quality correction coefficient corresponding to the current load segment and outputting it as the current coal quality correction coefficient;

[0040] The operating parameters include load and coal quantity; the N load segments do not overlap with each other; and N is a positive integer greater than or equal to 1.

[0041] In some embodiments, whether the unit is in steady state is first determined based on operating parameters such as unit load and coal quantity. A coal quality correction coefficient is then calculated for the steady state. Finally, a coal quality correction coefficient for each load segment is obtained based on the load segment. Compared to traditional coal quality correction coefficient calculation methods, this embodiment of the present invention takes into account conditions in different load segments, resulting in a coal quality coefficient that is closer to actual operating conditions. This ensures that the unit has separate coal quality coefficients for different load segments, eliminates the need for a PID control module, and enables faster coal quantity adjustment when coal quality changes, thereby ensuring economical operation of the unit.

[0042] Furthermore, the operating parameters also include: main steam pressure;

[0043] The sampling of the operating parameters of the unit to obtain sampling values ​​of the operating parameters, and determining the unit steady state, the load measurement value of the load, and the coal quantity measurement value of the coal quantity according to the sampling values ​​of the operating parameters, including:

[0044] Sampling at least one load sampling value of the load, judging the stability of the load according to the at least one load sampling value and outputting the load stability state of the load, and determining the load measurement value of the load according to the at least one load sampling value;

[0045] sampling at least one coal quantity sampling value of the coal quantity, judging the stability of the coal quantity according to the at least one coal quantity sampling value and outputting a coal quantity stable state of the coal quantity, and determining the coal quantity measurement value of the coal quantity according to the at least one coal quantity sampling value;

[0046] sampling a main steam pressure sampling value of the main steam pressure, judging the main steam pressure to be stable according to the main steam pressure sampling value and a preset main steam pressure range, and outputting a stable state of the main steam pressure;

[0047] The unit stable state is output according to the load stable state, the coal quantity stable state and the main steam pressure stable state; wherein, when the load stable state, the coal quantity stable state and the main steam pressure stable state are all stable, the unit stable state is stable, otherwise the unit stable state is unstable.

[0048] In some embodiments, by sampling the load and coal quantity multiple times, analyzing the sampled values ​​from the multiple samples to determine the load stable state and the coal quantity stable state, and calculating the load measurement value and the coal quantity measurement value through the sampled values ​​from the multiple samples, the interference of short-term fluctuations on the load stable state, the coal quantity stable state, the load measurement value and the coal quantity measurement value is avoided, thereby improving the stability of the system. A preset main steam pressure range is set according to the main steam pressure range during normal operation in a specific project, and the main steam pressure sampled values ​​can fluctuate within this range, thereby obtaining a stable main steam pressure stable state. The unit stable state is obtained by comprehensively combining the load stable state, the coal quantity stable state and the main steam pressure stable state, so that the obtained unit stable state more accurately reflects the actual stability of the current unit.

[0049] Furthermore, the sampling of the operating parameters of the unit to obtain sampled values ​​of the operating parameters, and determining the unit steady state, the load measurement value of the load, and the coal quantity measurement value of the coal quantity according to the sampled values ​​of the operating parameters, further comprising:

[0050] The operating parameters of the unit are periodically sampled at preset measurement time intervals to obtain sampling values ​​of the operating parameters, and the unit steady state, load measurement value of the load and coal quantity measurement value are determined based on the sampling values ​​of the operating parameters.

[0051] In some embodiments, in order to continuously monitor changes in coal quality and respond to changes in coal quality in real time, the operating parameters of the unit are periodically sampled at preset measurement time intervals to obtain sampling values ​​of the operating parameters, and the stable state of the unit, the load measurement value of the load, and the coal quantity measurement value of the coal quantity are determined based on the sampling values ​​of the operating parameters.

[0052] Furthermore, if Figure 3 、 Figure 4 、 Figure 5 As shown, the sampling of at least one load sampling value of the load, judging the stability of the load according to the at least one load sampling value and outputting the load stability state of the load, and determining the load measurement value of the load according to the at least one load sampling value include:

[0053] Inputting the measurement point signals corresponding to the load into the first lead-lag module 111 and the second lead-lag module 112 respectively;

[0054] Inputting the output signal of the first lead-lag module 111, the output signal of the second lead-lag module 112 and the measurement point signal corresponding to the load into the first three-value selection module 113;

[0055] using the quantity output signal output by the first three-value selection module 113 as the load measurement value, and inputting the logic output signal output by the first three-value selection module 113 into the first NOT gate 114;

[0056] Taking the output signal of the first NOT gate 114 as the load stable state;

[0057] Wherein, the time constant of the first lead-lag module 111 is different from the time constant of the second lead-lag module 112;

[0058] The step of sampling at least one coal quantity sampling value of the coal quantity, judging the stability of the coal quantity according to the at least one coal quantity sampling value and outputting a stable state of the coal quantity, and determining the coal quantity measurement value of the coal quantity according to the at least one coal quantity sampling value includes:

[0059] Inputting the measurement point signals corresponding to the coal quantity into the third lead-lag module 121 and the fourth lead-lag module 122 respectively;

[0060] Inputting the output signal of the third lead-lag module 121, the output signal of the fourth lead-lag module 122 and the measurement point signal corresponding to the coal quantity into the second three-value selection module 123;

[0061] The quantity output signal output by the second three-value selection module 123 is used as the coal quantity measurement value, and the logic output signal output by the second three-value selection module 123 is input to the second NOT gate 124;

[0062] The output signal of the second NOT gate 124 is used as the stable state of the coal quantity;

[0063] Wherein, the time constant of the third lead-lag module 121 is different from the time constant of the fourth lead-lag module 122;

[0064] The method of sampling the main steam pressure sampling value of the main steam pressure, judging the main steam pressure to be stable according to the main steam pressure sampling value and a preset main steam pressure range, and outputting the main steam pressure stable state includes:

[0065] Inputting the measurement point signal corresponding to the main steam pressure to the first over-limit alarm module 131;

[0066] Input the two logic output signals of the first over-limit alarm module 131 to the first OR gate 132;

[0067] Inputting the output signal of the first OR gate 132 to the third NOT gate 133;

[0068] The output signal of the third NOT gate 133 is used as the main steam pressure stable state;

[0069] The first over-limit alarm module 131 is configured to control both of its logic output signals to output FALSE when the measurement point signal corresponding to the main steam pressure inputted thereto is within a preset alarm upper limit and alarm lower limit range; otherwise, control at least one of its logic output signals to output TRUE;

[0070] The outputting of the unit stable state according to the load stable state, the coal quantity stable state and the main steam pressure stable state includes:

[0071] Input the coal quantity steady state output by the second NOT gate 124 and the main steam pressure steady state output by the third NOT gate 133 to the first AND gate 141;

[0072] Input the output signal of the first AND gate 141 to the second delayed-on module 144;

[0073] Input the load stable state output by the first NOT gate 114 to the first delayed opening module 143;

[0074] Input the output signal of the second delayed-on module 144 and the output signal of the first delayed-on module 143 to the second AND gate 142;

[0075] The output signal of the second AND gate 142 is used as the stable state of the unit.

[0076] In some embodiments, as Figure 3 、 Figure 4 、 Figure 5As shown, the measurement signal of load measurement point AI001 is connected to two lead-lag modules: a first lead-lag module 111 and a second lead-lag module 112. The output signals of first lead-lag module 111, second lead-lag module 112, and the corresponding load measurement point signal are simultaneously connected to a three-value selection module, namely, first three-value selection module 113. The output signal of the three-value selection module is the middle value of its three input signals. When the deviation between any two input signals is less than the set deviation, the logic output signal of the three-value selection module is FALSE (logically false). After passing through a NOT gate, namely, first NOT gate 114, the value becomes TRUE (logically true). The output signal of first NOT gate 114 is used as the load stability state. When the load stability state is TRUE, it indicates that the load is stable, and when the load stability state is FALSE, it indicates that the load is unstable. In some embodiments, the time constant of the first lead-lag module 111 is set to 180 seconds, the time constant of the second lead-lag module 112 is set to 360 seconds, and the set deviation of the first three-value selection module 113 is set to 3.5 MW, where MW represents megawatts.

[0077] The measurement signal from coal quantity measurement point AI002 is connected to two lead-lag modules: the third lead-lag module 121 and the fourth lead-lag module 122. The output signals of the third lead-lag module 121, the fourth lead-lag module 122, and the coal quantity measurement signal are simultaneously connected to a three-value selection module, namely the second three-value selection module 123. The quantity output signal of the three-value selection module is the middle value of its three input signals. When the deviation between any two input signals is less than the set deviation, the logic output signal of the three-value selection module is FALSE (logically false). After passing through the second NOT gate 124, the value becomes TRUE (logically true). The output signal of the second NOT gate 124 is used as the coal quantity stability state. When the coal quantity stability state is TRUE, the coal quantity is stable; when the coal quantity stability state is FALSE, the coal quantity is unstable. In some embodiments, the time constant of the third lead-lag module 121 is set to 180 seconds, and the time constant of the fourth lead-lag module 122 is set to 360 seconds; the setting deviation of the second three-value selection module 123 is 3t / h, where t / h represents tons / hour.

[0078] The measurement signal of the main steam pressure deviation measurement point AI003 is connected to the over-limit alarm module, namely the first over-limit alarm module 131. When the main steam pressure deviation is within the range from the lower alarm limit to the upper alarm limit, the two logic output signals of the first over-limit alarm module 131 are both FALSE. The output signal after connecting to the OR gate, namely the first OR gate 132, is FALSE, and after passing through the NOT gate, namely the third NOT gate 133, it becomes TRUE. The output signal of the third NOT gate 133 serves as the main steam pressure stability state. When the main steam pressure stability state is TRUE, it indicates that the main steam pressure is stable, and when the main steam pressure stability state is FALSE, it indicates that the main steam pressure is unstable. In some embodiments, the upper alarm limit of the first over-limit alarm module 131 is set to 0.3 MPa (megapascals), and the lower alarm limit of the first over-limit alarm module 131 is set to -0.3 MPa (megapascals).

[0079] The main steam pressure steady state output by the third NOT gate 133 and the coal quantity steady state output by the second NOT gate 124 are connected to the first AND gate 141 together. After a delay of 480 seconds by the second delay opening module 144, if the second delay opening module 144 outputs TRUE, it indicates that the coal quantity and main steam pressure remain in a steady state.

[0080] The load stable state of the output of the first NOT gate 114 is connected to a delay-on module, namely the first delay-on module 143. If the input signal before the first delay-on module 143 is delayed and is TRUE within the delay time, the output signal of the first delay-on module 143 becomes TRUE after the delay is opened. The output of the first delay-on module 143 being TRUE indicates that the load remains in a steady state.

[0081] The output signals of the first delayed opening module 143 and the second delayed opening module 144 are connected to the second AND gate 142. If the output of the second AND gate 142 is TRUE, it proves that the load, coal quantity and main steam pressure are all in a steady state, and the unit is also in a steady state.

[0082] The delay time of the first delayed opening module 143 is set to 480 seconds; the delay time of the second delayed opening module 144 is set to 480 seconds.

[0083] The load, coal quantity, and main steam pressure are measured and judged to be stable through hardware, and the unit status is ultimately judged to be stable, with high execution efficiency. Moreover, the above-mentioned hardware modules can all be implemented using modules in the control system tools already deployed in the existing production system, without the need for major changes to the production line.

[0084] Furthermore, if Figure 3 、 Figure 4 、 Figure 5As shown, when the unit is in a stable state, a coal quality correction coefficient is determined according to the load measurement value and the coal quantity measurement value, and the determined coal quality correction coefficient is used as a primary coal quality correction coefficient, including:

[0085] Input the load measurement value output by the first three-value selection module 113 as a dividend to the first divider 21;

[0086] Input the coal quantity measurement value output by the second three-value selection module 123 as a divisor to the first divider 21;

[0087] Using the division output signal of the first divider 21 as the first signal to be selected by the first selection module 23;

[0088] Using the stable state of the unit output by the second AND gate 142 as a channel selection signal of the first selection module 23;

[0089] Feedback the output signal of the first selection module 23 as the second signal to be selected by the first selection module 23;

[0090] Inputting the output signal of the first selection module 23 to the first filtering module 22;

[0091] Using the output signal of the first filtering module 22 as the first signal to be selected by the second selecting module 24;

[0092] Using the stable state of the unit output by the second AND gate 142 as a channel selection signal of the second selection module 24;

[0093] Feedback the output signal of the second selection module 24 as the second signal to be selected by the second selection module 24;

[0094] Using the output signal of the second selection module 24 as the primary coal quality correction coefficient;

[0095] The first selection module and the second selection module are the same selection module; the selection module is used to select one of the first candidate signal and the second candidate signal as the output signal according to the channel selection signal.

[0096] In some embodiments, as Figure 3 、 Figure 4 、 Figure 5As shown, when the unit's steady-state signal, i.e., the output signal of the second AND gate 142, is TRUE, the current coal quality coefficient can be calculated. The first divider 21 divides the intermediate value of the load, i.e., the quantity output signal of the first three-value selection module 113, by the intermediate value of the coal quantity, i.e., the quantity output signal of the second three-value selection module 123, to obtain a division output signal. The trigger output signal is latched by the first selection module 23 and then filtered by the first-order filter module 22 to obtain a filtered coal quality correction coefficient. The filtered coal quality correction coefficient is latched by the second selection module 24 as the primary coal quality correction coefficient calculated during the current unit steady-state period. The first and second selection modules 23 and 24 ensure that the primary coal quality correction coefficient is updated only during the unit's steady-state period. During unstable periods, the original or previously calculated primary coal quality correction coefficient is retained.

[0097] Further, if Figure 3 、 Figure 4 、 Figure 5 As shown, the method of periodically sampling the operating parameters of the unit at a preset measurement time interval to obtain sampling values ​​of the operating parameters, and determining the unit's stable state, load measurement value of the load, and coal quantity measurement value based on the sampling values ​​of the operating parameters, includes:

[0098] Input the stable state of the unit output by the second AND gate 142 to the third delayed start module 151;

[0099] Input the output signal of the third delayed-on module 151 to the fourth NOT gate 152;

[0100] The output signal of the fourth NOT gate 152 is input to the first AND gate 141 .

[0101] In some embodiments, as Figure 3 、 Figure 4 、 Figure 5 As shown, a loop is added to determine the steady state logic. The unit's steady state is output to the fourth NOT gate 152 after the delayed start of the third delayed start module 151. The output signal of the fourth NOT gate 152 is input to the first AND gate 141. The delay time set by the third delayed start module 151 controls the measurement interval, causing the unit's steady state to become FALSE after the measurement interval, prompting a re-determination of whether the unit is stable. In some embodiments, the delay time of the third delayed start module 151 is set to 120 seconds. This ensures that the unit's steady state becomes FALSE after 120 seconds, allowing a re-determination of whether the unit is in a steady state.

[0102] Furthermore, determining the current load segment in which the load sampling value is located from the preset N load segments includes:

[0103] Inputting the measurement point signal corresponding to the load to the first comparison input terminal of N+1 comparison modules 31; wherein the measurement point signal corresponding to the load is the sampled value of the load;

[0104] Inputting N+1 delimiting values ​​into the second comparison input terminals of N+1 comparison modules 31 in ascending order respectively;

[0105] For each group of two comparison modules 31 corresponding to adjacent delimiting values, the comparison logic output signal of the comparison module 31 inputting the larger delimiting value is inverted by the NOT gate 32 corresponding to the load segment corresponding to the adjacent delimiting value to obtain the upper limit comparison signal corresponding to the adjacent delimiting value, and the comparison logic output signal of the comparison module 31 inputting the smaller delimiting value is used as the lower limit comparison signal corresponding to the adjacent delimiting value. The upper limit comparison signal and the lower limit comparison signal corresponding to the adjacent delimiting value are ANDed by the AND gate 33 corresponding to the load segment corresponding to the adjacent delimiting value to obtain the working condition state signal corresponding to the load segment corresponding to the adjacent delimiting value;

[0106] Among them, the N load segments are continuously distributed and segmented by the N+1 boundary values, and every two adjacent boundary values ​​correspond to one load segment in the N load segments; if the working condition status signal corresponding to the load segment is TRUE, it means that the sampling value of the load is in the load segment, otherwise it means that the sampling value of the load is not in the load segment; the load segment whose working condition status signal is TRUE is the current load segment.

[0107] In some embodiments, Figure 3 、 Figure 4 、 Figure 5 The present embodiment is described using the specific embodiment shown as an example. Figure 3 In this example, 5 load segments and 5 corresponding working conditions are used. Figure 4 The number of load segments in the technical solution of the present invention is not a limitation of the present invention. The number of load segments in the technical solution of the present invention is N, and N is greater than or equal to 1. The specific number needs to be determined according to specific production requirements. Figure 4 Taking working condition 1 in the example, if the load value range is divided into N load segments, N+1 boundary values ​​are required, and correspondingly N+1 comparison modules are required. Figure 4 The load measurement point AI004 in the figure has the same sampling value as the load sampling point AI001 in the figure. The load measurement point AI004 is input to each comparison module. Figure 4 There are 6 dividing points, namely D1, D2, D3, D4, D5 and D6. The following is an example of D1 being 0MW, D2 being 87.5MW, D3 being 175MW, D4 being 262.5MW, D5 being 350MW and D6 being 380MW. Figure 4There are five load segments, namely, 0-87.5MW, 87.5-175MW, 175MW-262.5MW, 262.5MW-350MW and 350MW-380MW, where MW represents megawatts, corresponding to six boundary values ​​of 0, 87.5MW, 175MW, 262.5MW, 350MW and 380MW; the six boundary values ​​are input to the six comparison modules 31 in sequence; Figure 4 For example, working condition 1 in the example, working condition 1 corresponds to the load segment 0~87.5MW. Figure 4 The first comparison module 31 on the upper middle side compares the sampled value of the load from the load measurement point AI004 with the boundary value 0. If the sampled value of the load is greater than 0MW, the first comparison module 31 on the upper side outputs TRUE. Figure 4 The second comparison module 31 on the upper middle side compares the sampled value of the load from the load measuring point AI004 with the boundary value 87.5MW. If the sampled value of the load is less than 87.5MW, the output of the second comparison module 31 on the upper side is FALSE. The FALSE output of the second comparison module 31 on the upper side becomes TRUE after passing through the NOT gate, and then the output of the TRUE of the first comparison module 31 on the upper side is still TRUE after performing the AND operation through the AND gate. At this time, the measuring point BOPG001 is TRUE, which means that the load of the unit is between 0 and 87.5MW, that is, the operating state corresponding to the load segment 0 to 87.5MW (i.e. Figure 4 BOPG001 in the example is TRUE. At the same time, since the current load sampling value is between 0 and 87.5 MW, the operating conditions corresponding to other load segments will be FALSE. The operating conditions corresponding to other load segments are similar to those in operating condition 1.

[0108] Furthermore, when the unit is in a stable state, the primary coal quality correction coefficient is used to update the coal quality correction coefficient corresponding to the current load segment, and the coal quality correction coefficients corresponding to other load segments among the N load segments except the current load segment are maintained; when the unit is in an unstable state, the coal quality correction coefficients corresponding to all load segments are maintained, including:

[0109] For each of the N load segments, the output signal of the operating state signal corresponding to the load segment and the steady state of the unit after performing an AND operation through the AND gate 42 corresponding to the load segment is used as a latch enable signal of the follower 41 corresponding to the load segment, the primary coal quality correction coefficient is used as input data of the follower 41 corresponding to the load segment, and the output data of the follower 41 corresponding to the load segment is used as the coal quality correction coefficient corresponding to the load segment;

[0110] The follower 41 is configured to update the output data using the value of the input data when the latch enable signal is TRUE, and to maintain the value of the output data when the latch enable signal is FALSE.

[0111] In some embodiments, as Figure 3 、 Figure 4 、 Figure 5 As shown, in Figure 4 There are five load sections, namely 0-87.5MW, 87.5-175MW, 175MW-262.5MW, 262.5MW-350MW and 350MW-380MW, corresponding to five operating conditions respectively. The operating condition status signal DI001 of operating condition 1 comes from BOPG001, the operating condition status signal DI002 of operating condition 2 comes from BOPG002, the operating condition status signal DI003 of operating condition 3 comes from BOPG003, the operating condition status signal DI004 of operating condition 4 comes from BOPG004, the operating condition status signal DI005 of operating condition 5 comes from BOPG005, and the unit stable state signal DI006 comes from BOPG; Figure 5 The signal corresponding to the AI005 measuring point is the primary coal quality correction coefficient, which is input to the follower 41 corresponding to each load segment (for example Figure 5 The five TRAKs in the figure are the T pins of the five followers 41 as the input data of the follower 41; taking working condition 1 as an example, when the load measurement value is between 0 and 87.5MW and the unit is in a stable state, the working condition state signal corresponding to the load segment 0 to 87.5MW (i.e. Figure 5 DI001 in the unit) and the unit steady state (i.e. Figure 5 DI006 in the load section is still TRUE after the AND operation of the gate 42 corresponding to the load section 0 to 87.5MW. The signal after the AND operation is used as the latch enable signal (i.e. Figure 5 The S pin of TRAK in the current load segment is input to the follower 41. Since the signal obtained after the AND operation corresponding to the working condition 1 of the current load segment 0-87.5MW is TRUE, the follower 41 corresponding to the current load segment 0-87.5MW (equivalent to working condition 1) converts the primary coal quality correction coefficient (i.e. Figure 5 The AI005 in the load section) latches and updates the output data of the follower 41. At the same time, the working state signals corresponding to other load segments (in this embodiment, Figure 4 and Figure 5 The working condition signals corresponding to the other load segments are FALSE, and the output of the working condition signals corresponding to the stable state of the unit after passing through the AND gate corresponding to the corresponding load segment is FALSE, so the other load segments (in this embodiment, Figure 5The latch enable signal of the follower 41 corresponding to operating conditions 2, 3, 4, and 5 is FALSE, so the followers 41 corresponding to other load segments still maintain the original or last latched value as output data. This achieves the recording of the coal quality coefficient of each load segment in steady state. Figure 5 In the example, five followers 41( Figure 5 The OP pins of the five TRAKs in the output the coal quality correction coefficients corresponding to the five load segments respectively. The coal quality correction coefficients corresponding to the five load segments respectively correspond to the measuring points AO001, AO002, AO003, AO004, and AO005.

[0112] Furthermore, the reading of the coal quality correction coefficient corresponding to the current load segment and outputting it as the current coal quality correction coefficient includes:

[0113] For each of the N load segments, the operating condition signal corresponding to the load segment is used as the channel selection signal of the selection module 51 corresponding to the load segment, the coal quality correction coefficient corresponding to the load segment is used as the first candidate signal of the selection module 51 corresponding to the load segment, and the second candidate signal of the selection module 51 corresponding to the load segment is set to 0;

[0114] The output signals of all the selection modules 51 corresponding to the N load segments are input to the adder 52 to perform an addition operation, and the output signal of the adder 52 is used as the current coal quality correction coefficient.

[0115] In some embodiments, Figure 3 、 Figure 4 、 Figure 5 For example, Figure 5 In the embodiment, the five followers 41 each output a corresponding coal quality correction coefficient corresponding to the five load segments. The output signals of the five followers 41 are input to the five selection modules 51 as the five first candidate signals. The second candidate signals input to the five selection modules 51 are 0. The five working state signals corresponding to the five load segments (i.e. Figure 5DI001 to DI005) are input as five channel selection signals to five selection modules 51 respectively. Taking operating condition 1 as an example, when the load measurement value is in the load segment of 0-87.5MW, the operating condition status signal of operating condition 1 corresponding to the load segment 0-87.5MW is TRUE, and the operating condition status signals (DI002-DI005) corresponding to other load segments are FALSE. Then, the selection module 51 with DI001 as the channel selection signal selects the Pv1 channel (i.e., the channel connected to AO001), resulting in the output of the selection module 51 being updated to AO001, while the channel selection signal of the selection module 51 with other operating condition status signals (DI002-DI005) as the channel selection signal is FALSE, thereby selecting the channel Pv2 with a 0-value signal as the input. Therefore, the output signal of the selection module 51 with other operating condition status signals (DI002-DI005) as the channel selection signal is 0; the output signals of all selection modules 51 are still AO001 after being summed by the adder 52, that is, the final output AO006 at this time is the coal quality correction coefficient corresponding to the load segment 0-87.5MW. The same process applies when the load measurement value is in other load segments. By adding the outputs of the five selection modules, when the unit is in any load segment, the output of the selection module corresponding to that load segment is the coal quality correction coefficient corresponding to that load segment, and the outputs of the remaining selection modules are all 0. The final coal quality correction coefficient for the current load segment is AO006.

[0116] Furthermore, when the unit is in a stable state, determining a coal quality correction coefficient according to the load measurement value and the coal quantity measurement value, and using the determined coal quality correction coefficient as a primary coal quality correction coefficient, includes:

[0117] When the unit is in a stable state, filtering is performed on a result of dividing the load measurement value by the coal quantity measurement value to obtain the primary coal quality correction coefficient.

[0118] In some embodiments, the specific filtering method may be first-order filtering.

[0119] The embodiments of the present invention have the following beneficial effects: determining whether the unit is in steady state based on the unit load, coal quantity, and main steam pressure, then calculating the coal quality correction coefficient for the steady state, and finally obtaining the coal quality correction coefficient for each load segment. The coal quality correction coefficients obtained for different load segments are more closely aligned with actual operating conditions, ensuring that the unit has separate coal quality coefficients for different load segments. Without requiring a PID control module, the unit can more quickly adjust the coal quantity when the coal quality changes, thereby ensuring economical operation of the unit.

[0120] On the other hand, Figure 2 As shown, an embodiment of the present invention provides a load-staged coal quality correction coefficient control device, comprising:

[0121] The unit stability judgment and operating parameter measurement unit 10 is used to sample the operating parameters of the unit to obtain sampling values ​​of the operating parameters, and determine the unit stability state, load measurement value and coal quantity measurement value according to the sampling values ​​of the operating parameters;

[0122] a primary coal quality correction coefficient determining unit 20, configured to determine a coal quality correction coefficient according to the load measurement value and the coal quantity measurement value when the unit is in a stable state, and use the determined coal quality correction coefficient as the primary coal quality correction coefficient;

[0123] The load segment determination unit 30 is configured to determine the current load segment in which the load sampling value is located from among the preset N load segments;

[0124] The load segment coal quality correction coefficient updating unit 40 is configured to update the coal quality correction coefficient corresponding to the current load segment using the primary coal quality correction coefficient when the unit is in a stable state, and to maintain the coal quality correction coefficients corresponding to the other load segments among the N load segments except the current load segment; and to maintain the coal quality correction coefficients corresponding to all load segments when the unit is in an unstable state;

[0125] The current coal quality correction coefficient output unit 50 is used to read the coal quality correction coefficient corresponding to the current load segment and output it as the current coal quality correction coefficient;

[0126] The operating parameters include load and coal quantity; the N load segments do not overlap with each other; and N is a positive integer greater than or equal to 1.

[0127] Furthermore, the operating parameters also include: main steam pressure;

[0128] The unit stability determination and operating parameter measurement unit 10 includes:

[0129] a load stability determination and measurement module, configured to sample at least one load sampling value of the load, determine the stability of the load based on the at least one load sampling value and output a load stability state of the load, and determine the load measurement value of the load based on the at least one load sampling value;

[0130] a coal quantity stability judgment and measurement module, configured to sample at least one coal quantity sampling value of the coal quantity, judge the coal quantity to be stable according to the at least one coal quantity sampling value and output a coal quantity stability state of the coal quantity, and determine the coal quantity measurement value of the coal quantity according to the at least one coal quantity sampling value;

[0131] a main steam pressure stability judgment module, configured to sample a main steam pressure sampling value of the main steam pressure, judge the main steam pressure to be stable according to the main steam pressure sampling value and a preset main steam pressure range, and output a stable state of the main steam pressure;

[0132] The unit stability judgment module is used to output the unit stability state according to the load stability state, the coal quantity stability state and the main steam pressure stability state; wherein, when the load stability state, the coal quantity stability state and the main steam pressure stability state are all stable, the unit stability state is stable, otherwise the unit stability state is unstable.

[0133] Furthermore, the unit stability determination and operating parameter measurement unit 10 further includes:

[0134] The periodic stability judgment measurement trigger module is used to periodically sample the operating parameters of the unit at a preset measurement time interval to obtain the sampling values ​​of the operating parameters, and determine the unit's stable state, load measurement value and coal quantity measurement value based on the sampling values ​​of the operating parameters.

[0135] Furthermore, the load stability judgment and measurement module is specifically configured as follows: inputting the measurement point signal corresponding to the load into the first lead-lag module 111 and the second lead-lag module 112 respectively; inputting the output signal of the first lead-lag module 111, the output signal of the second lead-lag module 112, and the measurement point signal corresponding to the load into the first three-value selection module 113; using the quantity output signal output by the first three-value selection module 113 as the load measurement value, and inputting the logic output signal output by the first three-value selection module 113 into the first NOT gate 114; and using the output signal of the first NOT gate 114 as the load stability state;

[0136] Wherein, the time constant of the first lead-lag module 111 is different from the time constant of the second lead-lag module 112;

[0137] The coal quantity stability judgment and measurement module is specifically configured as follows: inputting the measurement point signal corresponding to the coal quantity to the third lead-lag module 121 and the fourth lead-lag module 122 respectively; inputting the output signal of the third lead-lag module 121, the output signal of the fourth lead-lag module 122, and the measurement point signal corresponding to the coal quantity to the second three-value selection module 123; using the quantity output signal output by the second three-value selection module 123 as the coal quantity measurement value, and inputting the logic output signal output by the second three-value selection module 123 to the second NOT gate 124; and using the output signal of the second NOT gate 124 as the coal quantity stability state;

[0138] Wherein, the time constant of the third lead-lag module 121 is different from the time constant of the fourth lead-lag module 122;

[0139] The main steam pressure stability judgment module is specifically configured to: input the measurement point signal corresponding to the main steam pressure to the first over-limit alarm module 131; input the two logic output signals of the first over-limit alarm module 131 to the first OR gate 132; input the output signal of the first OR gate 132 to the third NOT gate 133; and the output signal of the third NOT gate 133 is used as the main steam pressure stability state;

[0140] The first over-limit alarm module 131 is configured to control both of its logic output signals to output FALSE when the measurement point signal corresponding to the main steam pressure inputted thereto is within a preset alarm upper limit and alarm lower limit range; otherwise, control at least one of its logic output signals to output TRUE;

[0141] The unit stability judgment module is specifically configured as follows: the coal quantity stability state output by the second NOT gate 124 and the main steam pressure stability state output by the third NOT gate 133 are input to the first AND gate 141; the output signal of the first AND gate 141 is input to the second delayed opening module 144; the load stability state output by the first NOT gate 114 is input to the first delayed opening module 143; the output signal of the second delayed opening module 144 and the output signal of the first delayed opening module 143 are input to the second AND gate 142; and the output signal of the second AND gate 142 is used as the unit stability state.

[0142] Among them, the first lead-lag module 111, the second lead-lag module 112, the third lead-lag module 121 and the fourth lead-lag module 122 are all lead-lag modules; the lead-lag modules are used to sample the value of the input signal at their input end and transmit the sampled value to their output end as an output signal after a delay of a set time constant;

[0143] The first three-value selection module 113 and the second three-value selection module 123 are both three-value selection modules; the three-value selection modules include sampling input signals at their three input terminals, taking the middle value of the three input signals as a quantitative output signal, and setting their logical output signal to FALSE when the deviation of any two input signals is less than a set deviation, otherwise setting their logical output signal to TRUE; the set deviation value is a configurable parameter of the three-value selection module;

[0144] The first delayed opening module 143 and the second delayed opening module 144 are both delayed opening modules; the delayed opening module is used to delay its input terminal signal by a set delay time and then output it as its output signal.

[0145] Furthermore, the primary coal quality correction coefficient determination unit 20 is specifically configured to: input the load measurement value output by the first three-value selection module 113 as the dividend to the first divider 21; input the coal quantity measurement value output by the second three-value selection module 123 as the divisor to the first divider 21; use the division output signal of the first divider 21 as the first candidate signal for selection of the first selection module 23; use the unit stability state output by the second AND gate 142 as the channel selection signal of the first selection module 23; feed back the output signal of the first selection module 23 as the second candidate signal for selection of the first selection module 23; input the output signal of the first selection module 23 to the first filtering module 22; use the output signal of the first filtering module 22 as the first candidate signal for selection of the second selection module 24; use the unit stability state output by the second AND gate 142 as the channel selection signal of the second selection module 24; feed back the output signal of the second selection module 24 as the second candidate signal for selection of the second selection module 24; and use the output signal of the second selection module 24 as the primary coal quality correction coefficient;

[0146] The first selection module 23 and the second selection module 24 are the same selection modules; the selection modules are used to select one of the first candidate signal and the second candidate signal as the output signal according to the channel selection signal.

[0147] Furthermore, the periodic stability measurement trigger module is specifically configured as follows: inputting the stable state of the unit output by the second AND gate 142 to the third delayed opening module 151; inputting the output signal of the third delayed opening module 151 to the fourth NOT gate 152; and inputting the output signal of the fourth NOT gate 152 to the first AND gate 141.

[0148] Furthermore, the load segmentation determination unit 30 is specifically configured as follows: inputting the measurement point signal corresponding to the load to the first comparison input terminal of N+1 comparison modules 31; inputting N+1 boundary values ​​to the second comparison input terminal of the N+1 comparison modules 31 in ascending order; for the two comparison modules 31 corresponding to each group of adjacent boundary values, inverting the comparison logic output signal of the comparison module 31 inputting the larger boundary value through the NOT gate 32 corresponding to the load segment corresponding to the adjacent boundary value to obtain the upper limit comparison signal corresponding to the adjacent boundary value, and using the comparison logic output signal of the comparison module 31 inputting the smaller boundary value as the lower limit comparison signal corresponding to the adjacent boundary value; performing AND operation on the upper limit comparison signal and the lower limit comparison signal corresponding to the adjacent boundary value through the AND gate 33 corresponding to the load segment corresponding to the adjacent boundary value to obtain the working condition state signal corresponding to the load segment corresponding to the adjacent boundary value;

[0149] Among them, the measuring point signal corresponding to the load is the sampling value of the load; the N load segments are continuously distributed and segmented by the N+1 boundary values, and every two adjacent boundary values ​​correspond to one load segment in the N load segments; if the working condition status signal corresponding to the load segment is TRUE, it indicates that the sampling value of the load is in the load segment, otherwise it indicates that the sampling value of the load is not in the load segment; the load segment whose working condition status signal is TRUE is the current load segment.

[0150] Furthermore, the load segment coal quality correction coefficient updating unit 40 is specifically configured as follows: for each load segment in the N load segments, the operating condition signal corresponding to the load segment and the output signal of the unit stable state after performing an AND operation through the AND gate 42 corresponding to the load segment are used as the latch enable signal of the follower 41 corresponding to the load segment, the primary coal quality correction coefficient is used as the input data of the follower 41 corresponding to the load segment, and the output data of the follower 41 corresponding to the load segment is used as the coal quality correction coefficient corresponding to the load segment; the follower 41 is used to update the output data using the value of the input data when the latch enable signal is TRUE, and to maintain the value of the output data when the latch enable signal is FALSE.

[0151] Furthermore, the current coal quality correction coefficient output unit 50 is specifically configured as follows: for each load segment in the N load segments, the operating condition signal corresponding to the load segment is used as the channel selection signal of the selection module 51 corresponding to the load segment, the coal quality correction coefficient corresponding to the load segment is used as the first candidate signal of the selection module 51 corresponding to the load segment, and the second candidate signal of the selection module 51 corresponding to the load segment is set to 0; the output signals of all the selection modules 51 corresponding to the N load segments are input to the adder 52 to perform an addition operation, and the output signal of the adder 52 is used as the current coal quality correction coefficient.

[0152] Furthermore, the primary coal quality correction coefficient determination unit 20 includes:

[0153] When the unit is in a stable state, filtering is performed on a result of dividing the load measurement value by the coal quantity measurement value to obtain the primary coal quality correction coefficient.

[0154] The embodiment of the load-segmented coal quality correction coefficient control device provided in the embodiment of the present invention is an embodiment that corresponds one-to-one to the aforementioned load-segmented coal quality correction coefficient control method. The embodiment of the present invention can be understood based on the aforementioned load-segmented coal quality correction coefficient control method embodiment, and will not be repeated here.

[0155] The embodiments of the present invention have the following beneficial effects: determining whether the unit is in steady state based on the unit load, coal quantity, and main steam pressure, then calculating the coal quality correction coefficient for the steady state, and finally obtaining the coal quality correction coefficient for each load segment. The coal quality correction coefficients obtained for different load segments are more closely aligned with actual operating conditions, ensuring that the unit has separate coal quality coefficients for different load segments. Without requiring a PID control module, the unit can more quickly adjust the coal quantity when the coal quality changes, thereby ensuring economical operation of the unit.

[0156] The above technical solutions of the embodiments of the present invention are described in detail below with reference to specific application examples. For technical details not introduced during the implementation process, please refer to the relevant description above.

[0157] This embodiment of the present invention uses the algorithm function block of the Sciyon NT6000 system as an example to provide a load-segmented coal quality correction coefficient control device. The device utilizes a lead-lag module (LLAG), a three-value selection module (VOT), a selection module (SWCH), a first-order filter module (FILT), an over-limit alarm module (ANA), a comparison module, and an intelligent tracking module (TRAK). First, the device determines whether the unit is in steady state based on the unit load, coal quantity, and main steam pressure. It then calculates the primary coal quality correction coefficient for steady state. Finally, it divides the load into different sections to obtain the load-segmented coal quality correction coefficient. Compared to traditional coal quality coefficient calculation methods, this method takes into account the conditions at different load sections, resulting in a coal quality correction coefficient that is closer to actual operating conditions. This ensures that the unit has separate coal quality correction coefficients for different load sections, eliminates the need for a PID control module, and enables faster coal quantity adjustment when coal quality changes, ensuring economical operation.

[0158] The following is described with specific examples:

[0159] like Figure 3 、 Figure 4 、 Figure 5 As shown, an embodiment of the present invention provides a load-staged coal quality correction coefficient control method, which uses a lead-lag module (LLAG), a three-value selection module (VOT), a selection module (SWCH), a first-order filter module (FILT), an over-limit alarm module (ANA), a comparison module, an intelligent tracking module (TRAK), an addition module (ADD), a division module (DIV), an AND gate (AND), an OR gate (OR), a NOT gate (NOT) and a delayed opening module (TD).

[0160] The load segmented coal quality correction coefficient control method provided by the embodiment of the present invention includes three parts of logic: the first part calculates the coal quality correction coefficient as the primary coal quality correction coefficient based on the load, coal quantity and main steam pressure; the second part segments the load to determine which load segment the unit is currently in, and divides the load into five conditions, from operating conditions 1 to operating conditions 5, corresponding to five load segments; the third part calculates the coal quality correction coefficient of the load segment based on the coal quality correction coefficient obtained in the first part and the five operating conditions determined in the second part.

[0161] The first part of the logic is mainly used to determine whether the unit is in steady state and calculate the coal quality correction factor in steady state. The steady state judgment logic is based on the steady state judgment of load, coal quantity and main steam pressure.

[0162] To determine load steady-state, the load measurement point AI001 is connected to two lead-lag modules (the first lead-lag module 111 and the second lead-lag module 112), with time constants set to 180s and 360s, respectively. A three-value selection module (the first three-value selection module 113) is also connected to the measurement point AI001 itself. The output OP of the three-value selection module (the first three-value selection module 113) is the median value of the three inputs. When the deviation between any two inputs is less than the set deviation (initial value set to 3.5MW), the output OF is FALSE. After passing through a NOT gate (the first NOT gate 114), the value becomes TRUE. The output is then connected to a delayed-on module (the first delayed-on module 143) with a delay of 480s. If the signal before the delayed-on is TRUE for 480s, the signal after the delayed-on becomes TRUE, indicating that the load is in steady-state.

[0163] To determine the steady-state coal quantity, the coal quantity measurement point AI002 is connected to two lead-lag modules (the third lead-lag module 121 and the fourth lead-lag module 122), with their time constants set to 180s and 360s, respectively. This module, along with the measurement point AI002 itself, is also connected to a three-value selection module (i.e., the second three-value selection module 123). The output OP of the three-value selection module (i.e., the second three-value selection module 123) is the median value of the three inputs. When the deviation between any two inputs is less than the set deviation (initial value set to 3 t / h), the output OF is FALSE. After passing through a NOT gate (i.e., the second NOT gate 124), the value becomes TRUE.

[0164] Main steam pressure steady-state determination is implemented by connecting the main steam pressure deviation measuring point AI003 to the over-limit alarm module (ANA) (i.e., first over-limit alarm module 131). The module's upper and lower limits are initially set to ±0.3 MPa. When the pressure deviation is within the upper and lower limits, the module's second and third outputs are both FALSE. After connecting to an OR gate (i.e., first OR gate 132), the output is FALSE. After passing through a NOT gate (i.e., third NOT gate 133), the output becomes TRUE. This output, along with the steady-state signal for determining the coal quantity, is connected to an AND gate (i.e., first AND gate 141). After a 480-second delay-on module (i.e., second delay-on module 144), if this output is TRUE, it indicates that the coal quantity and main steam pressure remain steady. Finally, it is connected to an AND gate (i.e., second AND gate 142) along with the load steady-state signal (i.e., load stability). If the output of second AND gate 142 is TRUE, it indicates that the load, coal quantity, and main steam pressure are all steady-state, and the unit is also in steady-state.

[0165] When the unit's steady-state signal (i.e., the unit's stable state) is TRUE, the current coal quality correction coefficient can be calculated. The first divider 21 is used to divide the intermediate load value (i.e., the load measurement output by the first three-value selection module 113) by the intermediate coal quantity value (i.e., the coal quantity measurement output by the second three-value selection module 123). The resulting division result is filtered by the first filter module 22 to obtain the current coal quality correction coefficient as the primary coal quality correction coefficient. If the unit's steady-state signal is FALSE, the selection module (SWCH) (i.e., the first selection module 23 and the second selection module 24) self-holds. Simultaneously, a loop is added to determine the steady-state logic. The third delayed-on module 151 delays the unit's steady-state state for 120 seconds. The signal is then connected to the first AND gate 141 through a NOT gate (i.e., the fourth NOT gate 152). This ensures that the steady-state signal becomes FALSE after 120 seconds, allowing a re-determination of whether the unit is in steady state.

[0166] The second part of the logic is used to determine the load segment of the unit. Taking operating condition 1 as an example, the load measurement point AI004 is connected to the six comparison modules 31. If it is greater than 0MW, it outputs TRUE. If it is less than 87.5MW, it outputs FALSE. After passing through the NOT gate, it becomes TRUE. The two switch quantities are still TRUE after passing through the AND gate. It is judged that the unit load is between 0 and 87.5MW, and the BOPG001 value is 1. The same applies to other operating conditions.

[0167] The third logic section calculates the coal quality correction coefficient for each load segment. Measuring point AI005 represents the coal quality coefficient calculated by the first logic section, measuring points DI001-DI005 represent the outputs BOPG001-BOPG005 of the second logic section, and measuring point DI006 represents the steady-state determination of the first logic section. Taking operating condition 1 as an example, when the unit load is between 0 and 87.5 MW and the unit is in steady state, the output of the first tracking module (TRAK) (i.e., follower 41) is the value of AI005, and the tracking module's setpoint follows its output. If the unit load is between 0 and 87.5 MW but the unit is not in steady state (the value of DI006 is FALSE), the tracking module's output is its setpoint, i.e., the output when the previous unit was in steady state. This records the coal quality coefficient for this load segment in steady state, which is AO001. Subsequently, selection module 51 is connected, and the output is AO001 when the load is between 0 and 87.5 MW, and 0 otherwise. The same principle applies to the other load segments, resulting in the coal quality coefficients for the five steady-state load segments, AO001 to AO005. The outputs of the five selection modules 51 are then summed. When the unit is in any load segment, the output of that selection module 51 is the corresponding coal quality coefficient, while the outputs of the remaining selection modules 51 are all 0. The resulting coal quality correction coefficient for each load segment is AO006.

[0168] Another specific embodiment is described below:

[0169] A load-stage coal quality correction coefficient control scheme overcomes the shortcomings of the original BTU coefficient correction scheme, such as untimely adjustment, incorrect adjustment direction, and no load segmentation. It can determine whether the unit is in a steady state and quickly correct when the coal quality changes, so that the unit can timely correct the coal quantity during the variable load stage and achieve segmented processing of the coal quality correction coefficient, which is closer to the actual operating conditions.

[0170] The embodiment of the present invention takes a 350MW coal-fired unit as an example to provide a load-stage coal quality correction coefficient control method, including the following steps:

[0171] Load measurement point AI001 is connected to two lead-lag modules (LLAGs) (first lead-lag module 111 and second lead-lag module 112), with time constants set to 180s and 360s, respectively. Measurement point AI001 itself is also connected to a three-value selection module (VOT) (first three-value selection module 113), with the initial deviation set to 3.5MW. The output pin OP of first three-value selection module 113 is connected to a divider module (DIV) (first divider 21), and the output pin OF is connected to a NOT gate (first NOT gate 114). This pin is then connected to a 480s delay-on module (TD) (first delay-on module 143), and finally to an AND gate (second AND gate 142).

[0172] Coal quantity measurement point AI002 is connected to two lead-lag modules (i.e., third lead-lag module 121 and fourth lead-lag module 122), with their time constants set to 180s and 360s, respectively. The measurement point itself is also connected to a three-value selection module (i.e., second three-value selection module 123), with the initial deviation set to 3 t / h. The output pin OP of the second three-value selection module 123 is connected to a divider module (i.e., first divider 21), and the output pin OF of the second three-value selection module 123 is connected to a NOT gate (i.e., second NOT gate 124), which is then connected to an AND gate (i.e., first AND gate 141).

[0173] The main steam pressure deviation measuring point AI003 is connected to the over-limit alarm module (ANA) (i.e., the first over-limit alarm module 131). The upper and lower limits of the module are initially set to ±0.3MPa. The second output and the third output of the module are connected to the OR gate (i.e., the first OR gate 132), and then connected to the AND gate (i.e., the first AND gate 141) after passing through the NOT gate (i.e., the third NOT gate 133), and then connected to the 480s delay opening module (i.e., the second delay opening module 144), and finally connected to the AND gate (i.e., the second AND gate 142).

[0174] The output of the division module (i.e., the first divider 21) is connected to the selection module (SWCH) (i.e., the first selection module 23), and then connected to the first-order filtering module (FILT) (i.e., the first filtering module 22), and then connected to a selection module (i.e., the second selection module 24). The final output is the coal quality correction coefficient ROPG, which serves as the primary coal quality correction coefficient.

[0175] The output of the second AND gate 142 is the steady-state judgment BOPG (i.e., the stable state of the unit), and is respectively connected to the two selection modules (i.e., the first selection module 23 and the second selection module 24). The output of the second AND gate 142 also passes through a 120s delayed opening module (i.e., the third delayed opening module 151), connects to the NOT gate (i.e., the fourth NOT gate 152), and then connects to the first AND gate 141.

[0176] The load range is divided according to the unit's conditions. In this embodiment, the unit load is divided into five ranges: 0-87.5MW, 87.5-175MW, 175MW-262.5MW, 262.5MW-350MW, and 350MW-380MW. Load measurement point AI004 is connected to six comparison modules 31, and the values ​​of the six comparison modules 31 are set to 0, 87.5, 175, 262.5, 350, and 380, respectively.

[0177] Figure 3 、 Figure 4 、 Figure 5 In the figure, from top to bottom, the outputs of comparison modules 31 No. 1 to 5 are connected to five AND gates 33 respectively. The outputs of comparison modules 31 No. 2 to 6 are connected to AND gates 33 respectively after passing through NOT gates 32. The outputs of the five AND gates 33 are BOPG001 to BOPG005, representing working conditions 1 to 5.

[0178] Take the input points DI001-DI005 as the values ​​of BOPG001-BOPG005, AI005 as the value of ROPG, and DI006 as the value of BOPG. DI006 is connected in parallel with each of DI001-DI005, connected to five AND gates 42. The output of each AND gate 42 is then connected to the corresponding tracking module (TRAK) (i.e., follower 41). Then, let AI005 connect to each tracking module (i.e., follower 41), and the outputs of the five tracking modules (i.e., follower 41) are AO001-AO005. At the same time, let the outputs of the five tracking modules (i.e., followers 41) and DI001-DI005 be connected to the five selection modules 51 respectively. The outputs of all selection modules 51 are added together to obtain the final load segment coal quality correction coefficient, which is AO006, as the coal quality correction coefficient corresponding to the current load segment.

[0179] It should be understood that the specific order or hierarchy of steps in the disclosed processes is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of the present disclosure. The accompanying method claims present elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0180] In the foregoing detailed description, various features are grouped together in a single embodiment to simplify the disclosure. This method of disclosure should not be interpreted as reflecting an intention that embodiments of the claimed subject matter require more features than are expressly recited in each claim. On the contrary, as reflected in the appended claims, the invention comprises less than all the features of any individual disclosed embodiment. The appended claims are hereby expressly incorporated into the detailed description, with each claim standing on its own as a separate preferred embodiment of the invention.

[0181] The above description of the disclosed embodiments is intended to enable any person skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the spirit and scope of the present disclosure. Therefore, the present disclosure is not limited to the embodiments presented herein but is intended to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0182] The above description includes examples of one or more embodiments. Of course, it is impossible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but it will be appreciated by those skilled in the art that the various embodiments may be further combined and arranged. Therefore, the embodiments described herein are intended to encompass all such changes, modifications and variations that fall within the scope of protection of the appended claims. In addition, to the extent the term "comprising" is used in the specification or claims, the term is intended to be encompassed in a manner similar to the term "including". In addition, any use of the term "or" in the specification of the claims is intended to mean a "non-exclusive or".

[0183] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A load-stage coal quality correction coefficient control method, characterized in that: include: Sampling the operating parameters of the unit to obtain sampling values ​​of the operating parameters, and determining the unit steady state, a load measurement value of the load, and a coal quantity measurement value of the coal quantity according to the sampling values ​​of the operating parameters; When the unit is in a stable state, determining a coal quality correction coefficient according to the load measurement value and the coal quantity measurement value, and using the determined coal quality correction coefficient as a primary coal quality correction coefficient; Determining a current load segment in which the sampled value of the load is located from among the preset N load segments; When the unit is in a stable state, the coal quality correction coefficient corresponding to the current load segment is updated using the primary coal quality correction coefficient, and the coal quality correction coefficients corresponding to the other load segments among the N load segments except the current load segment are maintained; When the stable state of the unit is unstable, the coal quality correction coefficients corresponding to all load segments are maintained, specifically comprising: for each load segment in N load segments, using the working state signal corresponding to the load segment and the output signal of the stable state of the unit after performing an AND operation through an AND gate (42) corresponding to the load segment as a latch enable signal of a follower (41) corresponding to the load segment, using the primary coal quality correction coefficient as input data of the follower (41) corresponding to the load segment, and using the output data of the follower (41) corresponding to the load segment as the coal quality correction coefficient corresponding to the load segment; the follower (41) is used to update the output data using the value of the input data when the latch enable signal is TRUE, and to maintain the value of the output data when the latch enable signal is FALSE; The method further comprises: for each load segment in N load segments, using the working state signal corresponding to the load segment as the channel selection signal of the selection module (51) corresponding to the load segment, using the coal quality correction coefficient corresponding to the load segment as the first candidate signal of the selection module (51) corresponding to the load segment, and setting the second candidate signal of the selection module (51) corresponding to the load segment to 0; inputting the output signals of all the selection modules (51) corresponding to the N load segments into an adder (52) to perform an addition operation, and using the output signal of the adder (52) as the current coal quality correction coefficient; The operating parameters include load and coal quantity; the N load segments do not overlap with each other; and N is a positive integer greater than or equal to 1.

2. The load-stage coal quality correction coefficient control method according to claim 1, characterized in that: The operating parameters also include: main steam pressure; The sampling of the operating parameters of the unit to obtain sampling values ​​of the operating parameters, and determining the unit steady state, the load measurement value of the load, and the coal quantity measurement value of the coal quantity according to the sampling values ​​of the operating parameters, including: Sampling at least one load sampling value of the load, judging the stability of the load according to the at least one load sampling value and outputting the load stability state of the load, and determining the load measurement value of the load according to the at least one load sampling value; sampling at least one coal quantity sampling value of the coal quantity, judging the stability of the coal quantity according to the at least one coal quantity sampling value and outputting a coal quantity stable state of the coal quantity, and determining the coal quantity measurement value of the coal quantity according to the at least one coal quantity sampling value; sampling a main steam pressure sampling value of the main steam pressure, judging the main steam pressure to be stable according to the main steam pressure sampling value and a preset main steam pressure range, and outputting a stable state of the main steam pressure; The unit stable state is output according to the load stable state, the coal quantity stable state and the main steam pressure stable state; wherein, when the load stable state, the coal quantity stable state and the main steam pressure stable state are all stable, the unit stable state is stable, otherwise the unit stable state is unstable.

3. The load-stage coal quality correction coefficient control method according to claim 2, characterized in that: The sampling of the operating parameters of the unit to obtain sampled values ​​of the operating parameters, and determining the unit's stable state, a load measurement value of the load, and a coal quantity measurement value of the coal quantity based on the sampled values ​​of the operating parameters, further comprising: The operating parameters of the unit are periodically sampled at preset measurement time intervals to obtain sampling values ​​of the operating parameters, and the unit steady state, load measurement value of the load and coal quantity measurement value are determined based on the sampling values ​​of the operating parameters.

4. The load-stage coal quality correction coefficient control method according to claim 3, characterized in that: The sampling of at least one load sampling value of the load, judging the stability of the load according to the at least one load sampling value and outputting the load stability state of the load, and determining the load measurement value of the load according to the at least one load sampling value include: Inputting the measurement point signals corresponding to the load into the first lead-lag module (111) and the second lead-lag module (112) respectively; Inputting the output signal of the first lead-lag module (111), the output signal of the second lead-lag module (112), and the measurement point signal corresponding to the load into a first three-value selection module (113); Using the quantity output signal output by the first three-value selection module (113) as the load measurement value, and inputting the logic output signal output by the first three-value selection module (113) into a first NOT gate (114); Taking the output signal of the first NOT gate (114) as the load stable state; wherein the time constant of the first lead-lag module (111) and the time constant of the second lead-lag module (112) are different; The step of sampling at least one coal quantity sampling value of the coal quantity, judging the stability of the coal quantity according to the at least one coal quantity sampling value and outputting a stable state of the coal quantity, and determining the coal quantity measurement value of the coal quantity according to the at least one coal quantity sampling value includes: Inputting the measurement point signals corresponding to the coal quantity into the third lead-lag module (121) and the fourth lead-lag module (122) respectively; Inputting the output signal of the third lead-lag module (121), the output signal of the fourth lead-lag module (122), and the measurement point signal corresponding to the coal quantity into a second three-value selection module (123); The quantity output signal output by the second three-value selection module (123) is used as the coal quantity measurement value, and the logic output signal output by the second three-value selection module (123) is input to the second NOT gate (124); Taking the output signal of the second NOT gate (124) as the stable state of the coal quantity; wherein the time constant of the third lead-lag module (121) is different from the time constant of the fourth lead-lag module (122); The method of sampling the main steam pressure sampling value of the main steam pressure, judging the main steam pressure to be stable according to the main steam pressure sampling value and a preset main steam pressure range, and outputting the main steam pressure stable state includes: Inputting a measurement point signal corresponding to the main steam pressure into a first over-limit alarm module (131); Inputting two logic output signals of the first over-limit alarm module (131) into a first OR gate (132); Inputting the output signal of the first OR gate (132) to the third NOT gate (133); The output signal of the third NOT gate (133) serves as the main steam pressure stable state; The first over-limit alarm module (131) is configured to control both of its logic output signals to output FALSE when the measurement point signal corresponding to the main steam pressure inputted thereto is within a preset alarm upper limit and alarm lower limit range, and otherwise control at least one of its logic output signals to output TRUE; The outputting of the unit stable state according to the load stable state, the coal quantity stable state and the main steam pressure stable state includes: Inputting the coal quantity steady state output by the second NOT gate (124) and the main steam pressure steady state output by the third NOT gate (133) into the first AND gate (141); Inputting the output signal of the first AND gate (141) to the second delayed-on module (144); Inputting the load stable state output by the first NOT gate (114) to a first delayed-on module (143); Inputting the output signal of the second delayed-on module (144) and the output signal of the first delayed-on module (143) into a second AND gate (142); The output signal of the second AND gate (142) is used as the stable state of the unit.

5. The load-stage coal quality correction coefficient control method according to claim 4, characterized in that: When the unit is in a stable state, determining a coal quality correction coefficient according to the load measurement value and the coal quantity measurement value, and using the determined coal quality correction coefficient as a primary coal quality correction coefficient, includes: Inputting the load measurement value output by the first three-value selection module (113) as a dividend into a first divider (21); Inputting the coal quantity measurement value output by the second three-value selection module (123) as a divisor into the first divider (21); using the division output signal of the first divider (21) as a first signal to be selected by a first selection module (23); using the stable state of the unit output by the second AND gate (142) as a channel selection signal of the first selection module (23); Feeding back the output signal of the first selection module (23) as a second signal to be selected by the first selection module (23); Inputting the output signal of the first selection module (23) into the first filtering module (22); Using the output signal of the first filtering module (22) as the first signal to be selected by the second selecting module (24); using the stable state of the unit output by the second AND gate (142) as a channel selection signal of the second selection module (24); Feedback the output signal of the second selection module (24) as a second signal to be selected by the second selection module (24); using the output signal of the second selection module (24) as the primary coal quality correction coefficient; The first selection module and the second selection module are the same selection module; the selection module is used to select one of the first candidate signal and the second candidate signal as the output signal according to the channel selection signal.

6. The load-stage coal quality correction coefficient control method according to claim 5, characterized in that: The step of periodically sampling the operating parameters of the unit at a preset measurement time interval to obtain sampling values ​​of the operating parameters, and determining the unit's steady state, a load measurement value of the load, and a coal quantity measurement value based on the sampling values ​​of the operating parameters, includes: Inputting the stable state of the unit output by the second AND gate (142) into a third delayed opening module (151); Inputting the output signal of the third delayed-on module (151) to the fourth NOT gate (152); The output signal of the fourth NOT gate (152) is input to the first AND gate (141).

7. The load-stage coal quality correction coefficient control method according to claim 6, characterized in that: The determining of the current load segment in which the sampled load value is located from the preset N load segments includes: Inputting the measurement point signal corresponding to the load to the first comparison input terminal of N+1 comparison modules; wherein the measurement point signal corresponding to the load is a sampled value of the load; Inputting N+1 delimiting values ​​into the second comparison input terminals of N+1 comparison modules (31) in ascending order respectively; For each group of two comparison modules (31) corresponding to adjacent delimiting values, the comparison logic output signal of the comparison module (31) inputting the larger delimiting value is inverted through a NOT gate (32) corresponding to the load segment corresponding to the adjacent delimiting value to obtain an upper limit comparison signal corresponding to the adjacent delimiting value, the comparison logic output signal of the comparison module (31) inputting the smaller delimiting value is used as a lower limit comparison signal corresponding to the adjacent delimiting value, and the upper limit comparison signal and the lower limit comparison signal corresponding to the adjacent delimiting value are ANDed through an AND gate (33) corresponding to the load segment corresponding to the adjacent delimiting value to obtain an operating condition signal corresponding to the load segment corresponding to the adjacent delimiting value; Among them, the N load segments are continuously distributed and segmented by the N+1 boundary values, and every two adjacent boundary values ​​correspond to one load segment in the N load segments; if the working condition status signal corresponding to the load segment is TRUE, it means that the sampling value of the load is in the load segment, otherwise it means that the sampling value of the load is not in the load segment; the load segment whose working condition status signal is TRUE is the current load segment.

8. A load-stage coal quality correction coefficient control device, characterized in that: include: The unit stability judgment and operating parameter measurement unit is used to sample the operating parameters of the unit to obtain sampling values ​​of the operating parameters, and determine the unit stability state, load measurement value and coal quantity measurement value based on the sampling values ​​of the operating parameters; a primary coal quality correction coefficient determination unit, configured to determine a coal quality correction coefficient according to the load measurement value and the coal quantity measurement value when the unit is in a stable state, and use the determined coal quality correction coefficient as the primary coal quality correction coefficient; A load segment determination unit, configured to determine a current load segment in which the load sampling value is located from among N preset load segments; The load segment coal quality correction coefficient updating unit is used to update the coal quality correction coefficient corresponding to the current load segment using the primary coal quality correction coefficient when the unit is in a stable state, and to maintain the coal quality correction coefficients corresponding to the other load segments except the current load segment in the N load segments; and to maintain the coal quality correction coefficients corresponding to all load segments when the unit is in an unstable state; the specific configuration is: for each load segment in the N load segments, the operating condition signal corresponding to the load segment and the unit stable state are updated through the load segment. The output signal after the AND operation of the AND gate (42) corresponding to the segment is used as a latch enable signal of the follower (41) corresponding to the load segment, the primary coal quality correction coefficient is used as input data of the follower (41) corresponding to the load segment, and the output data of the follower (41) corresponding to the load segment is used as the coal quality correction coefficient corresponding to the load segment; the follower (41) is used to update the output data using the value of the input data when the latch enable signal is TRUE, and to maintain the value of the output data when the latch enable signal is FALSE; The current coal quality correction coefficient output unit is used to read the coal quality correction coefficient corresponding to the current load segment and output it as the current coal quality correction coefficient. The specific configuration is as follows: for each load segment in N load segments, the working condition signal corresponding to the load segment is used as the channel selection signal of the selection module (51) corresponding to the load segment, the coal quality correction coefficient corresponding to the load segment is used as the first candidate signal of the selection module (51) corresponding to the load segment, and the second candidate signal of the selection module (51) corresponding to the load segment is set to 0; the output signals of all the selection modules (51) corresponding to the N load segments are input to the adder (52) to perform addition operation, and the output signal of the adder (52) is used as the current coal quality correction coefficient; The operating parameters include load and coal quantity; the N load segments do not overlap with each other; and N is a positive integer greater than or equal to 1.

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