A method and system for evaluating power upper limit of thermal power units based on coal quality analysis

Abstract

The present invention provides a method for evaluating the upper limit of power of a thermal power unit based on coal quality analysis, including obtaining the real-time active power, the real-time total coal supply and the power rising interval of the thermal power unit; obtaining the historical coal quality evaluation coefficient by using the power rising interval; obtaining the upper limit of the maximum active power by using the real-time active power and the real-time total coal supply of the thermal power unit and the historical coal quality evaluation coefficient; cross-validating and dynamically correcting the upper limit of the maximum active power and the real-time active power to obtain a dynamic judgment of the final power change. The present invention analyzes the historical operation data to establish a database of the coal quality of the unit operation, and then uses a search method to judge the real-time coal quality of the unit operation, evaluate the upper limit of the unit operation power, and make up for the lack of evaluation of the frequency regulation and peak regulation capabilities of the unit in the past.

Description

Technical Field

[0001] The present invention relates to the technical field of network-source coordinated control, and in particular to a method and system for evaluating the power upper limit of a thermal power unit based on coal quality analysis. Background Art

[0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art.

[0003] As the installed capacity of new energy generating units continues to increase, coal-fired power units are changing from the main power source to a basic power source that provides peak and frequency regulation functions, and the proportion of renewable energy in energy consumption continues to increase. However, new energy power generation is affected by external factors such as weather and geography, and is characterized by randomness, intermittence and instability. The large-scale integration of new energy units into the power grid will bring great challenges to the current traditional controllable and stable power system. The load volatility of the system is becoming more and more obvious, and the pressure on frequency and peak regulation in the regional power grid will also increase.

[0004] In order to ensure the stability and controllability of the new power system, the demand for frequency-modulation and peak-shaving power sources is gradually increasing. Coal-fired thermal power generation, as a conventional power source, needs to bear the heavy task of frequency-modulation and peak-shaving of the power grid. The primary frequency regulation of thermal power generating units is mainly to adjust the air intake regulating door of the digital electro-hydraulic control system of the steam turbine, control the heat storage during boiler combustion, quickly respond to the requirements of the power grid when the power grid is abnormal, stabilize the power grid frequency and ensure the safety of the power grid. At the same time, when the output of new energy sources such as wind power and photovoltaic power generation is too much or insufficient, thermal power generating units need to play the role of deep peak regulation to ensure the power supply and load balance of the power grid. As the main component of the current power grid and the main support for frequency-modulation and peak-shaving, the tasks of thermal power generating units are becoming more and more arduous. However, thermal power generating units are currently facing production problems such as uneven fuel quality and high prices.

[0005] At present, power generation companies are facing the severe challenge of not being able to buy thermal coal or even if they can buy thermal coal, it is mixed with a large amount of low calorific value coal. The power generation efficiency of power generation companies is not high and they cannot provide reliable backup power support for the operation of large power grids. In this situation, in order to ensure the safety and stability of power grid operation, it is necessary to evaluate the coal quality of the unit operation and analyze in real time the power limit that can be achieved by the current unit burning raw materials, so that power generation companies and power grid operators can regulate the operation of the unit. Summary of the invention

[0006] In order to solve the above problems, the present invention proposes a method and system for evaluating the power upper limit of a thermal power unit based on coal quality analysis. The present invention can classify the quality of the burned coal according to the historical operation data of the unit, and then evaluate the upper limit of the real-time output of the unit, providing a basis for power generation enterprises and power grid operators to control the unit.

[0007] According to some embodiments, the present invention adopts the following technical solutions:

[0008] A method for evaluating the power upper limit of a thermal power unit based on coal quality analysis, comprising:

[0009] Obtain the real-time active power, real-time total coal supply and power increase interval of the thermal power unit;

[0010] The historical coal quality assessment coefficient is obtained by using the power increase interval;

[0011] The upper bound of the maximum active power is obtained by using the real-time active power of the thermal power unit, the real-time total coal supply and the historical coal quality evaluation coefficient;

[0012] The upper limit of the maximum active power and the real-time active power are cross-validated and dynamically corrected to obtain a dynamic judgment of the final power change.

[0013] Furthermore, it also includes obtaining the operating data and signals of the thermal power unit, specifically including the active power of the thermal power unit, the total coal feed, the pulverizer load current, the primary frequency regulation front load command signal and the primary frequency regulation front load command signal.

[0014] Furthermore, the obtaining of the power rising interval segment includes taking the historical data before the current running time as an evaluation sample and selecting a rising interval segment sequence that satisfies the maximum power value within a set interval.

[0015] Furthermore, the method of obtaining the historical coal quality evaluation coefficient by utilizing the power increase interval includes obtaining the active power increment, coal feed increment and the ratio of the power increment to the coal feed increment in different power increase intervals according to the data of different power increase intervals to obtain the historical coal quality evaluation coefficient.

[0016] Furthermore, the upper limit of the maximum active power is calculated by a real-time coal quality coefficient, and the real-time coal quality coefficient is obtained by comparing the real-time operating power data of the thermal power unit with the historical coal quality assessment coefficient.

[0017] Furthermore, the obtaining of the power rising interval segment includes taking into account the influence of primary frequency modulation and selecting continuous data segments of set interval values ​​to extract the power rising interval segment.

[0018] Furthermore, the fixed interval value includes a signal interval in which the absolute value of the difference between the load command signal before the primary frequency modulation and the load command signal after the primary frequency modulation is less than 5.

[0019] A power upper limit assessment system for thermal power units based on coal quality analysis, comprising:

[0020] An operation data acquisition module is configured to acquire operation data and signals of the thermal power unit and a power increase interval;

[0021] The real-time data acquisition module is configured to acquire the real-time active power and the real-time total coal supply of the thermal power unit;

[0022] The historical evaluation module is configured to obtain a historical coal quality evaluation coefficient using the power increase interval;

[0023] The active power module is configured to obtain the upper limit of the maximum active power by using the real-time active power and the real-time total coal supply of the thermal power unit and the historical coal quality evaluation coefficient;

[0024] The dynamic judgment module is configured to cross-validate and dynamically correct the upper limit of the maximum active power and the real-time active power to obtain a dynamic judgment of the final power change amount.

[0025] A computer-readable storage medium stores a plurality of instructions, wherein the instructions are suitable for being loaded and executed by a processor of a terminal device, a method for evaluating the power upper limit of a thermal power unit based on coal quality analysis.

[0026] A terminal device includes a processor and a computer-readable storage medium, wherein the processor is used to implement various instructions; the computer-readable storage medium is used to store multiple instructions, wherein the instructions are suitable for being loaded by the processor and executing the power upper limit assessment method of a thermal power unit based on coal quality analysis.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The present invention analyzes the unit operation data, establishes a historical database of the unit operation coal quality, and then uses a search method to judge the unit's real-time operation coal quality, evaluates the upper limit of the unit's operating power, and makes up for the lack of evaluation of the unit's frequency regulation and peak regulation capabilities in the past;

[0029] The evaluation method provided by the present invention has strong universality and can be applied to units with different installed capacities. According to the method provided by the present invention, the power upper limit values ​​of different units during real-time operation can be derived, providing a basis for power generation companies and power grid operators to control units, improving the level of scientific power grid dispatching, and providing support for the reserve power of large power grids. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings in the specification, which constitute a part of the present application, are used to provide further understanding of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute improper limitations on the present application.

[0031] Figure 1 It is a flow chart of the power upper limit evaluation method of a thermal power unit based on coal quality analysis of the present invention;

[0032] Figure 2It is a schematic diagram of a power upper limit assessment system for a thermal power unit based on coal quality analysis of the present invention;

[0033] Figure 3 This is a power upper limit assessment diagram for a 650MW operating unit based on coal quality assessment;

[0034] Figure 4 This is the power upper limit assessment diagram for a 330MW operating unit based on coal quality assessment. DETAILED DESCRIPTION

[0035] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0036] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0037] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0038] Example 1.

[0039] like Figure 1 As shown, the present invention provides a method for evaluating the power upper limit of a thermal power unit based on coal quality analysis, comprising:

[0040] Obtain the operation data and signals of thermal power units and the power increase interval;

[0041] Obtain the real-time active power and total coal supply of thermal power units;

[0042] The historical coal quality assessment coefficient is obtained by using the power increase interval;

[0043] The upper bound of the maximum active power is obtained by using the real-time active power of the thermal power unit, the real-time total coal supply and the historical coal quality evaluation coefficient;

[0044] The upper limit of the maximum active power and the real-time active power are cross-validated and dynamically corrected to obtain a dynamic judgment of the final power change.

[0045] Furthermore, the operating data and signals of the thermal power unit include the active power of the thermal power unit, the total coal feed rate, the coal mill load current, and the load command signal before and after the primary frequency modulation.

[0046] Furthermore, the obtaining of the power rising interval segment includes taking the historical data before the current running time as an evaluation sample and selecting a rising interval segment sequence that satisfies the maximum power value within a set interval.

[0047] Furthermore, the method of obtaining the historical coal quality evaluation coefficient by utilizing the power increase interval includes obtaining the active power increment, coal feed increment and the ratio of the power increment to the coal feed increment in different power increase intervals according to the data of different power increase intervals to obtain the historical coal quality evaluation coefficient.

[0048] Furthermore, the upper limit of the maximum active power is calculated by a real-time coal quality coefficient, and the real-time coal quality coefficient is obtained by comparing the real-time operating power data of the thermal power unit with the historical coal quality assessment coefficient.

[0049] Furthermore, the obtaining of the power rising interval segment includes taking into account the influence of primary frequency modulation and selecting continuous data segments of set interval values ​​to extract the power rising interval segment.

[0050] Furthermore, the fixed interval value includes a signal interval in which the absolute value of the difference between the load command signal before the primary frequency modulation and the load command signal after the primary frequency modulation is less than 5.

[0051] Specifically,

[0052] like Figure 1 As shown, the method in this embodiment includes the following process:

[0053] S1: Extract the power rising interval according to the collected signals such as unit active power, total coal feed, coal mill load current, load instructions before and after primary frequency modulation, etc.;

[0054] S2: Calculate the coal quality evaluation database of the unit based on the data of different power rise sections and obtain the historical coal quality evaluation coefficient K h ;

[0055] S3: Collect the real-time active power value P of the unit Actual , Real-time total coal supply value T Actual , calculated and compared with the historical coal quality assessment coefficient K h Compare and obtain the real-time coal quality coefficient K a , using the real-time coal quality coefficient K a The upper limit of the maximum active power that the computer group can achieve in real time is P pre-max ;

[0056] S4: P through the coal mill load current pre-max and P Actual Carry out cross-validation and dynamic correction, and make dynamic judgment on the power change according to the final result.

[0057] Furthermore, the historical data before the current running time is used as the evaluation sample. The evaluation sample is updated iteratively with the change of running time. The influence of the frequency modulation is considered when processing the data. forward -C back |<5 continuous data segments are used to extract the power rising interval segment, where C forward Indicates the load command signal before primary frequency modulation, C back Indicates the load command signal after primary frequency regulation; the rated power of the unit is P Rated [0.9,1] is taken as the maximum load variation interval, and a rising interval sequence is selected to satisfy the maximum power value within this interval;

[0058] Furthermore, assuming that the coal quality burned in the unit does not change within 2 hours, according to the data obtained in different power increase intervals, the active power increment, coal feed increment and the ratio of power increment to coal feed increment within 2 hours in different power increase intervals are calculated respectively, and the maximum power value P of different power increase intervals is recorded. max , maximum coal feed rate T max ; The calculation formula for the historical coal quality assessment coefficient is:

[0059]

[0060] Among them, ΔP i is the active power increment in different rising sections, ΔT i is the increment of coal feeding amount in different ascending sections, t Actual Indicates the current running time, t 2hour Indicates the running time 2 hours ago, K hi is the evaluation coefficient of different historical coal qualities;

[0061] Furthermore, the maximum coal delivery capacity of the pulverizer track is determined. Assuming that |K hi -K hj |≤0.05 is the historical coal quality coefficient for the same type of coal quality, and the maximum coal feed rate T max The average value is taken as the maximum coal delivery amount of the same coal quality track, and the maximum coal delivery amount T in the coal quality database is corrected. max ;

[0062] Furthermore, the upper limit of the maximum power of the unit in real-time operation is obtained according to the current real-time active power, the current coal quality and the increase in the amount of coal feed, and the calculation formula is P pre-max =P Actual +K a ×(T max -T Actual ), K a is the coal quality coefficient at the current operating time, T maxis the maximum coal supply corresponding to the current coal quality coefficient;

[0063] Furthermore, assuming that the coal quality in the unit remains unchanged within 30 minutes during actual operation, the power-to-coal ratio is obtained by dividing the difference in active power between the unit's real-time operation and the unit's operation 30 minutes ago by the difference in total coal supply. The coal quality coefficient K at the current operating moment of the unit is a The power-coal ratio and the historical coal quality database K h The coal quality database K closest to the ratio is selected. h As the coal quality coefficient K at the current operating time a ;

[0064] Furthermore, when the upper limit of the maximum power is greater than the rated power, that is, P pre-max >P Rated When the current coal quality can meet the power increment required for deep peak regulation, the maximum power change of the unit ΔP=P Rated -P Actual ; When the upper limit of the maximum power is less than the rated power, that is, P pre-max <P Rated When the maximum power change of the unit is ΔP=P pre-max -P Actual ,At this time, the coal quality cannot meet the power increment required for deep peak regulation, and power generation companies and grid operators can adjust the units according to the situation;

[0065] Furthermore, when the upper limit of the maximum power is less than the actual operating power of the unit, that is, P pre-max <P Actual The data sampling at the current moment may be abnormal. The coal quality classification calculation method requires accurate sampling data. Wrong data points will lead to reduced evaluation accuracy. When the unit is actually running, there is a certain linear relationship between the coal mill load current and the coal feed rate. The coal mill load current correction coefficient Υ is introduced. i The coal quality upper limit assessment algorithm is verified, and the coal feed rate change range corresponding to different load current correction coefficients is established based on historical experience. i The calculation formula is Among them I e represents the rated current of the coal mill, n represents the number of coal mills put into operation, I ij It represents the load current of the jth coal mill put into operation;

[0066] Furthermore, when the power evaluation at a certain point is abnormal, it is determined whether the current coal feed rate is in the coal feed rate variation range corresponding to the pulverizer load current, and whether the coal feed rate data is abnormal; if the coal feed rate data is abnormal, the mean of the variation range is selected as the current point coal feed rate to correct the data.

[0067] Example 2.

[0068] A power upper limit assessment system for thermal power units based on coal quality analysis, comprising:

[0069] The data acquisition module is configured to obtain the real-time active power, the real-time total coal supply and the power increase interval of the thermal power unit;

[0070] The historical evaluation module is configured to obtain a historical coal quality evaluation coefficient using the power increase interval;

[0071] The active power module is configured to obtain the upper limit of the maximum active power by using the real-time active power and the real-time total coal supply of the thermal power unit and the historical coal quality evaluation coefficient;

[0072] The dynamic judgment module is configured to cross-validate and dynamically correct the upper limit of the maximum active power and the real-time active power to obtain a dynamic judgment of the final power change amount.

[0073] Example 3.

[0074] Figure 2 Schematic diagram of the power upper limit assessment system of a thermal power unit based on coal quality analysis of the present invention. Figure 2 As shown, the power upper limit assessment system comprises:

[0075] Divider module DIV1, multiplier module MUL1, adder module ADD1, subtractor module DEV1, subtractor module DEV2, subtractor modules DEV31~DEV3 j , subtractor module DEV4, subtractor module DEV5, subtractor module DEV6, summation module SUM1, absolute value modules ABS1~ABSj, multiple-select selector module SELECT1, comparator modules CMP11~CMP1 j , comparator module CMP2, comparator module CMP3, analog selector module AXSEL11~AXSEL1 j , analog selector module AXSEL2, analog selector module AXSEL3, hysteresis module LAG1, hysteresis module LAG2, logic and module AND1, logic exclusive or module XOR1, logic not module NOT11~NOT1 j , logical NOT module NOT2, logical NOT module NOT3, logical NOT module NOT4, coal quality assessment database module, coal mill load current cross-validation module;

[0076] The active power value, total coal supply value, pulverizer current, and load instructions before and after primary frequency modulation in the unit's 90-day historical operation data are sent to the coal quality evaluation database module to calculate the historical coal quality evaluation coefficient K h1 , K h2 , …, Khj , and the maximum coal feed rate T corresponding to different coal quality coefficients max Assuming that the coal quality of the unit remains unchanged within 30 minutes during the actual operation, the actual power PA of the unit collected ctual One path is sent to the first input end of the subtractor module DEV1, and the other path is sent to the second input end of the subtractor module DEV1 after passing through the lag module LAG1. The time lag parameter is set by the lag module LAG1 to represent the unit operating power 30 minutes ago. The lag time constant parameter of the LAG1 module is set to 1800. Similarly, the actual total coal supply TA collected by the unit ctual One path is sent to the first input end of the subtractor module DEV2, and the other path is sent to the second input end of the subtractor module DEV2 after passing through the lag module LAG2. The time lag parameter is set by the lag module LAG2 to represent the unit operating power 30 minutes ago. The lag time constant parameter of the LAG2 module is set to 1800. The output of the subtractor module DEV1 and the output of the subtractor module DEV2 are respectively the real-time operating power change of the unit within 30 minutes and the total coal supply change, which are sent to the first input end and the second input end of the divider module DIV1 respectively;

[0077] The coal quality evaluation coefficient K of the coal quality evaluation database h1 , K h2 , …, K hj Sent to subtractor modules DEV31~DEV3 respectively j The second input terminal of the subtractor module DEV31~DEV3 j The first input terminal receives the output of the divider module DIV1, and DEV31~DEV3 j The outputs of each are respectively obtained through the absolute value modules ABS1~ABSj to obtain the ratio of the real-time operating power change to the total coal feed change and the coal quality evaluation coefficient K h1 , K h2 , …, K hj The outputs of the absolute value modules ABS1-ABSj are respectively sent to the 1st to jth input terminals of the multiple-choice-one selector module SELECT1. The multiple-choice-one selector module SELECT1 is composed of a plurality of three-choice-one selector modules and is used to select the minimum value among the multiple inputs for output;

[0078] Furthermore, the historical coal quality evaluation coefficient closest to the real-time operating power-to-coal ratio is selected, and the outputs of the absolute value modules ABS1~ABSj are sent to the comparator modules CMP11~CMP1 j The output of the multiple-select selector module SELECT1 is sent to the comparator modules CMP11~CMP1 jThe second input terminal of the analog selector AXSEL11 to AXSEL1 selects the output signal of the smallest absolute value module ABS1 to ABSj. j The first input end receives the historical coal quality evaluation coefficient K h1 , K h2 , …, K hj , the second input terminal is set to a constant 0, analog selector module AXSEL11~AXSEL1 j The set end receives the comparator module CMP11~CMP1 j The respective outputs of the logic NOT modules NOT11 to NOT1 j Inverted signal, AXSEL11~AXSEL1 j The output signal of the summation module SUM1 is composed of 1 non-zero signal and j-1 zero signals. The non-zero signal is the historical coal quality evaluation coefficient closest to the actual operation situation. The 1st to jth input terminals of the summation module SUM1 receive AXSEL11~AXSEL1 j The output signal is used to calculate the real-time coal quality evaluation coefficient K a ;

[0079] The coal quality evaluation database receives the output signal of the summation module SUM1 and then gives the corresponding coal quality coefficient K a Maximum coal feed output signal T max The input end of the subtractor module DEV4 receives the maximum coal feed output signal T max and the real-time total coal supply of the unit T Actual , calculate the additional coal feed margin that can be added during the operation of the unit; the coal feed margin is sent to the first input end of the multiplier module MUL1, and the output signal of the summation module SUM1 is sent to the second input end of the multiplier module MUL1 to calculate the additional power that can be added during the operation of the unit; the input end of the adder module ADD1 receives the actual power value P of the unit respectively Actual The output signal of the multiplier module MUL1 is used to calculate the upper limit of the maximum power of the unit in real time operation P pre-max ;

[0080] Furthermore, the upper limit of the maximum power of the unit in real time operation P pre-max The accuracy is judged, and the output of the adder module ADD1 is sent to the second input terminal of the comparator module CMP2. Actual The output value of the comparator module CMP2 is 0101, which indicates the actual power value P of the unit. Actual Less than the upper limit of the maximum power of the unit in real time operation P pre-maxThe input end of the logic XOR module XOR1 receives the output of the comparator module CMP2 and the binary value 0101, respectively, to determine the actual power value P of the unit. Actual Is it less than the upper limit of the unit's real-time maximum power P? pre-max The output of the logic exclusive OR module XOR1 is inverted by the logic NOT module NOT2 and sent to the set end of the analog selector module AXSEL2. The first input end of the analog selector module AXSEL2 is the upper limit of the maximum power of the unit in real time operation P pre-max , the second input terminal is set to a constant 0; further, when the output of the analog selector module AXSEL2 is not zero, the output is the upper limit of the maximum power of the unit in real time operation P pre-max Otherwise, the output signal is inverted by the logic NOT module NOT2 to positively trigger the coal mill load current cross-verification module, and determine whether it is a data abnormality error based on the relationship between the coal mill load current data and the coal feed amount;

[0081] The output of the adder module ADD1 is sent to the second input terminal of the comparator module CMP3. Rated The first input terminal of the comparator module CMP3 is sent to the input terminal of the logic XOR module XOR2, and the output of the comparator module CMP3 and the binary value 0101 are received respectively to determine the rated power P of the unit. Rated Is it less than the upper limit of the unit's real-time maximum power P? pre-max ; The input end of the subtractor module DEV5 receives the rated power P of the unit Rated And the actual power value of the unit P Actual The input end of the subtractor module DEV6 receives the upper limit of the maximum power of the unit in real time operation P pre-max And the actual power value of the unit P Actual , the output signals of the subtractor modules DEV5 and DEV6 are respectively sent to the first input terminal and the second input terminal of the analog quantity selector module AXSEL3, the output signals of the logic negation modules NOT2 and NOT3 are sent to the input terminal of the logic and module AND1, and the output signal of the logic and module AND1 is used as the set input of the analog quantity selector module AXSEL3, that is, when the upper limit of the maximum power of the unit in real time operation is correctly evaluated and the upper limit of the maximum power is greater than the rated power value of the unit, the maximum power change ΔP of the unit is the rated power P of the unit. Rated With real-time power P Actual Otherwise, the maximum power change of the unit ΔP is the upper limit of the maximum power P pre-max The actual power value P Actual The difference.

[0082] Taking a regional power grid in North China as an example, an application example of the method proposed in the present invention in an actual power grid is given.

[0083] A 650MW supercritical single intermediate reheat unit and a 300MW subcritical single intermediate reheat unit were selected for analysis respectively.

[0084] The operation data of the first 90 days of the history of a 650MW supercritical single intermediate reheat unit was selected to establish a coal quality evaluation database. In order to avoid interference from the primary frequency modulation process, |C forward -C back |<5 is used as a constraint to process the data. Unit rated power P Rated is 650MW, and the maximum load range of the rising section is [0.9P Rated ,P Rated ], that is, [585MW, 650MW]. Assuming that the coal quality burned in the unit does not change within 2 hours, the power increase interval that meets the requirements is obtained. Calculate the active power increment ΔP of each increase interval respectively i , coal feed increment ΔT i . The historical coal quality evaluation coefficient is calculated by the formula K hi =ΔP i / ΔT i Calculate the historical coal quality evaluation coefficient K h1 , K h2 , …, K hj , and record the maximum coal feed rate T that the unit can achieve under different historical coal quality assessment coefficients max ; Coal quality assessment database | K hi -K hj |≤0.05 coal quality coefficient is the same type of coal quality, and the maximum coal feed rate T max The average value is taken as the maximum coal delivery amount of the same coal quality track, and the maximum coal delivery amount T in the coal quality database is corrected. max , the operating coal quality evaluation database of the unit is obtained as shown in Table 1.

[0085] Table 1

[0086]

[0087] Furthermore, the power upper limit of the real-time running unit is evaluated. Assuming that the coal quality of the unit remains unchanged for a period of time, the power upper limit of the unit in the next 30 minutes is evaluated by analyzing the coal quality of the first 30 minutes of operation. The power-to-coal ratio is obtained by dividing the difference in active power between the real-time operation of the unit and the operation 30 minutes ago by the difference in total coal supply. The power-to-coal ratio is then compared with the coal quality database K h Match and select the coal quality database K that is closest to the ratio h As the coal quality coefficient K at the current operating time a .

[0088] Then, the upper power limit of the unit in the next 30 minutes can be calculated. The upper limit of the maximum power of the unit in real time operation is obtained according to the current real-time active power, current coal quality and the increase in coal supply. The calculation formula is P pre-max =P Actual +K a ×(T max -T Actual ), K a is the coal quality coefficient at the current operating time, T max It is the maximum coal supply corresponding to the current coal quality coefficient.

[0089] At a certain moment, the real-time power P of the unit is collected Actual =513.896602MW, the total real-time coal supply of the unit is T Actual =244.955412T / h. Assuming that the coal quality of the unit remains unchanged within 30 minutes during the actual operation, the collected real-time power value of the unit and the real-time total coal supply value of the unit are respectively sent to the lag modules LAG1 and LAG2 with a set value of 1800 for lag calculation to obtain the power value and total coal supply value of the unit 30 minutes ago; the real-time power value of the unit and the power value of the unit 30 minutes ago are sent to the X1 and X2 input terminals of the subtractor module DEV1 to obtain the real-time operating power change of the unit, and the real-time coal supply value of the unit and the total coal supply value of the unit 30 minutes ago are sent to the X1 and X2 input terminals of the subtractor module DEV2 to obtain the total coal supply change of the unit; the real-time operating power change of the unit and the total coal supply change are sent to the X1 and X2 input terminals of the divider module DIV1 to calculate the power-to-coal ratio K=1.39447; the power-to-coal ratio is sent to DEV31~DEV3 j X1 input terminal, subtractor module DEV31~DEV3 j The X2 input terminal receives the historical coal quality evaluation coefficient K of the coal quality evaluation database h1 , K h2 , …, K hj ; DEV31~DEV3 j The output Y of each module is used to obtain the ratio of the real-time operating power change to the total coal supply change and the coal quality evaluation coefficient K through the absolute value modules ABS1~ABSj. h1 , K h2 , …, K hj The output signal Y of the absolute value modules ABS1~ABSj is sent to the X1 to Xj input terminals of the multiple-selection selector module SELECT1 respectively. The output signal Y of the multiple-selection selector module SELECT1 selects the smallest difference and is sent to the comparator modules CMP11~CMP1 j Then it is determined that the difference of the second result is the smallest; the comparator modules CMP11~CMP1 jThe output signal Y passes through the logic NOT module NOT11~NOT1 j After being inverted, they are sent to the analog selector modules AXSEL11~AXSEL1 j The set terminal S of the analog selector module AXSEL11~AXSEL1 j The X1 input terminal receives the historical coal quality evaluation coefficient K h1 , K h2 , …, K hj , the X2 input terminal is set to a constant 0. As a result, except for the output signal Y of the analog selector module AXSEL12, which is 1.47789, the output signals Y of the other modules are all 0; after being obtained by the summation module SUM1, the coal quality evaluation coefficient K2 = 1.47789 is the coal quality coefficient closest to the actual operation of the unit, that is, the real-time coal quality coefficient K a =1.47789, corresponding to coal quality coefficient K a Maximum coal feed rate T max =262.309074T / h;

[0090] The maximum coal feed rate T max =262.309074T / h and real-time total coal supply T Actual =244.955412T / h is sent to the X1 and X2 input terminals of the subtractor module DEV4 to obtain the coal supply margin ΔT=17.353662T / h that can be increased during the unit operation. The coal supply margin and the unit real-time coal quality coefficient K a The X1 and X2 input terminals of the multiplier module MUL1 are sent to obtain the power that can be increased during the operation of the unit ΔP = 25.646804MW; the Z1 and Z2 input terminals of the adder module ADD1 receive the real-time power of the unit and the power that can be increased during the operation of the unit, and obtain the upper limit of the maximum power of the real-time operation of the unit P pre-max =539.543406MW; send the upper limit of the group's real-time maximum power and the group's real-time power to the X1 and X2 input terminals of the comparator module CMP2. The output signal Y of the comparator module CMP2 is XORed with the binary number 0101 by the logic XOR module XOR1. pre-max >P Actual Therefore, the output signal of the logic exclusive OR module XOR1 is inverted by the logic NOT module NOT2 and then output 1 to the set terminal S of the analog selector module AXSEL2. The X1 input terminal of the analog selector module AXSEL2 is the upper limit P of the maximum power of the unit in real time operation. pre-max , the X2 input terminal is set to a constant 0, that is, the data is normal. At this time, the maximum operating power upper limit of the unit is P pre-max =539.543406MW;

[0091] Furthermore, the rated power P Rated=650MW and the upper limit of the maximum operating power of the unit are sent to the comparator module CMP3. The output signal Y of the comparator module CMP3 is XORed with the binary number 0101 by the logic XOR module XOR2. Rated >P pre-max Therefore, the output signal of the logic exclusive OR module XOR2 is inverted by the NOT module NOT3 and then output 0 to the Z1 input terminal of the logic AND module AND1. The Z2 input terminal of the AND1 module receives the output signal of the logic NOT module NOT2. The output signal 0 of the AND1 module is sent to the set terminal S of the analog selector module AXSEL3. The X1 input terminal of the analog selector module AXSEL3 is P calculated by the subtractor module DEV5. Rated -P Actual , X2 input is P calculated by subtractor module DEV6 pre-max -P Actual At this time, the output signal of the analog selector module AXSEL3 selects the set value of X2, that is, the upper limit of the maximum operating power of the unit P pre-max =539.543406MW.

[0092] Select multiple operating moments to evaluate the power limit. The power limit of the unit for the next 30 minutes is as follows: Figure 3 Similarly, the 300MW subcritical single intermediate reheat unit is analyzed. The historical data of the 300MW subcritical single intermediate reheat unit in the first 90 days is selected for analysis. The power upper limit of the 300MW subcritical single intermediate reheat unit at different times in the next 30 minutes is as follows: Figure 4 shown.

[0093] Example 4.

[0094] A computer-readable storage medium stores a plurality of instructions, wherein the instructions are suitable for being loaded and executed by a processor of a terminal device, a method for evaluating the power upper limit of a thermal power unit based on coal quality analysis.

[0095] Example 5.

[0096] A terminal device includes a processor and a computer-readable storage medium, wherein the processor is used to implement various instructions; the computer-readable storage medium is used to store multiple instructions, wherein the instructions are suitable for being loaded by the processor and executing the power upper limit assessment method of a thermal power unit based on coal quality analysis.

[0097] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0098] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0099] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0100] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0101] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

[0102] Although the above describes the specific implementation mode of the present invention in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims

1. A method for evaluating the upper limit of power of a thermal power unit based on coal quality analysis, characterized in that: include: Obtaining the operation data and signals of thermal power units and the power increase interval; The thermal power unit operation data and signals include the thermal power unit active power, total coal feed, grinding Coal machine load current, load command signal before and after primary frequency modulation; The use of the power increase interval to obtain the historical coal quality evaluation coefficient includes obtaining the active power increment, coal feed increment and the ratio of the power increment to the coal feed increment in different power increase intervals according to the data of different power increase intervals, and obtaining the historical coal quality evaluation coefficient; the calculation formula of the historical coal quality evaluation coefficient is: in, is the active power increment in different rising sections, is the increment of coal feeding amount in different ascending sections, Indicates the current running time. Indicates the running time 2 hours ago. is the evaluation coefficient of different historical coal quality; using the real-time active power of the thermal power unit, the real-time total coal supply and the historical coal quality evaluation coefficient, the upper limit of the maximum active power is obtained, and the calculation formula is P pre-max =P Actual +K a ×(T max -T Actual ), P Actual is the real-time active power value, K a is the coal quality coefficient at the current operating time, T max is the maximum coal feed rate corresponding to the current coal quality coefficient, T Actual It is the real-time total coal supply value; Coal quality coefficient K at the current operating time of the unit a The power-coal ratio and the historical coal quality database K h The coal quality database K closest to the ratio is selected. h As the coal quality coefficient K at the current operating time a ; The upper limit of the maximum active power and the real-time active power are cross-validated and dynamically corrected to obtain a dynamic judgment of the final power change.

2. A method for evaluating the power upper limit of a thermal power unit based on coal quality analysis as claimed in claim 1, characterized in that: The obtaining of the power rising interval segment includes taking the historical data before the current running time as an evaluation sample and selecting a rising interval segment sequence that satisfies the maximum power value within a set interval.

3. A method for evaluating the power upper limit of a thermal power unit based on coal quality analysis as claimed in claim 1, characterized in that: The obtaining of the power rising interval segment includes taking into account the influence of primary frequency modulation and selecting continuous data segments of set interval values ​​to extract the power rising interval segment.

4. A method for evaluating the upper limit of power of a thermal power unit based on coal quality analysis as claimed in claim 3, characterized in that: The fixed interval value includes a signal interval in which the absolute value of the difference between the load command signal before the primary frequency modulation and the load command signal after the primary frequency modulation is less than 5.

5. A power upper limit assessment system for thermal power units based on coal quality analysis, characterized in that: include: The data acquisition module is configured to acquire the operation data and signals of the thermal power unit and the power increase interval; The thermal power unit operation data and signals include the thermal power unit active power, total coal feed, grinding Coal machine load current, load command signal before and after primary frequency modulation; The historical evaluation module is configured to obtain the historical coal quality evaluation coefficient by using the power increase interval, including obtaining the active power increment, coal feed increment and the ratio of the power increment to the coal feed increment in different power increase intervals according to the data of different power increase intervals, and obtaining the historical coal quality evaluation coefficient; The calculation formula of the historical coal quality assessment coefficient is: in, is the active power increment in different rising sections, is the increment of coal feeding amount in different ascending sections, Indicates the current running time. Indicates the running time 2 hours ago. is the evaluation coefficient of different historical coal qualities; The active power module is configured to use the real-time active power of the thermal power unit, the real-time total coal supply, and the historical coal quality evaluation coefficient to obtain the upper limit of the maximum active power. The calculation formula is P pre-max =P Actual +K a ×(T max -T Actual ), P Actual is the real-time active power value, K a is the coal quality coefficient at the current operating time, T max is the maximum coal feed rate corresponding to the current coal quality coefficient, T Actual It is the real-time total coal supply value; Coal quality coefficient K at the current operating time of the unit a The power-coal ratio and the historical coal quality database K h The coal quality database K closest to the ratio is selected. h As the coal quality coefficient K at the current operating time a ; The dynamic judgment module is configured to cross-validate and dynamically correct the upper limit of the maximum active power and the real-time active power to obtain a dynamic judgment of the final power change amount.

6. A computer-readable storage medium, characterized in that: A plurality of instructions are stored therein, and the instructions are suitable for being loaded by a processor of a terminal device and executed in accordance with any one of claims 1 to 4, a method for evaluating the power upper limit of a thermal power unit based on coal quality analysis.

7. A terminal device, characterized in that: It includes a processor and a computer-readable storage medium, the processor is used to implement various instructions; the computer-readable storage medium is used to store multiple instructions, and the instructions are suitable for being loaded by the processor and executed by a power upper limit assessment method for a thermal power unit based on coal quality analysis as described in any one of claims 1-4.

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