Coal-fired unit 20% load control method

Abstract

The invention discloses a 20% load control method for a coal-fired unit, and is applied to the technical field of deep peak regulation. Comprising the following steps: acquiring a difference value between a real-time load and a target load of a current total coal-fired unit; determining an adjusting instruction of the total coal-fired unit load; acquiring operation data of the coal-fired units and determining the coal-fired units capable of carrying out load adjustment; determining a load regulation sequence of the adjustable coal-fired unit; determining the load adjusting capacity of all the adjustable coal-fired units, and distributing load adjusting targets according to the load adjusting sequence; and a response scheme is determined, load adjustment is conducted according to the response scheme, and the load of the total coal-fired unit is adjusted to the target load. According to the method, the load of the coal-fired power unit is adjusted, the coal-fired power unit can quickly respond to the external load change, meanwhile, the load adjusting cost is considered, the external load demand change is met, and various energy resources can be utilized more reasonably and efficiently.

Description

Technical Field

[0001] The present invention relates to the technical field of deep peak regulation, and more specifically to a 20% load control method for a coal-fired unit. Background Art

[0002] With the widespread application of various clean energy sources, the problem of power supply and demand balance and system peak load regulation capacity has become increasingly prominent. Since clean energy is unstable and the load demand of the power grid will also change, the load regulation capacity of coal-fired units has become very important. The load control of coal-fired units is not only related to the safe and stable operation of the power system, but also directly affects the effective utilization and economic benefits of various energy resources in the power market. The existing peak load regulation schemes pay too much attention to the maximum adjustable capacity of coal-fired units, especially when the load is as low as 20%. In order to achieve the target load, the regulation cost is too high, and even affects the safe operation of the coal-fired units. Therefore, how to provide a 20% load control method for coal-fired units is a problem that technicians in this field urgently need to solve. Summary of the invention

[0003] In view of this, the present invention provides a 20% load control method for a coal-fired unit, which takes into account the operation status and regulation cost of the coal-fired unit when determining the regulation scheme, and solves the problems existing in the prior art.

[0004] In order to achieve the above object, the present invention provides the following technical solutions:

[0005] A 20% load control method for a coal-fired unit comprises the following steps:

[0006] S1. Obtain the real-time load and target load of the current total coal-fired units, and determine the difference between the real-time load and the target load;

[0007] S2, determining the adjustment instruction of the total coal-fired unit load based on the difference between the real-time load and the target load;

[0008] S3, obtaining the operation data of the coal-fired units and determining the coal-fired units that can be load-regulated;

[0009] S4, determining a load adjustment sequence of the adjustable coal-fired unit based on the operation data of the adjustable coal-fired unit and the cost data of load adjustment;

[0010] S5. Determine the load regulation capabilities of all adjustable coal-fired units and allocate load regulation targets according to the load regulation sequences of the adjustable coal-fired units;

[0011] S6. Determine a response plan based on the load regulation target of the adjustable coal-fired units and perform load regulation according to the response plan, so that the load of the total coal-fired units is adjusted to the target load.

[0012] Optionally, in S2, if the real-time load of the total coal-fired units is greater than the target load, the adjustment instruction is to reduce the load; if the real-time load of the total coal-fired units is less than the target load, the adjustment instruction is to increase the load.

[0013] Optional, S3 is:

[0014] S31. Obtaining the operation safety index of the coal-fired unit;

[0015] S32. Determine the weight of each operational safety indicator according to its impact on the safety situation;

[0016] S33, calculating the safety evaluation score of the coal-fired unit based on the operation safety index and the corresponding weight;

[0017] S34. If the safety evaluation score of the coal-fired unit is greater than a preset threshold, it is determined as a coal-fired unit that can be load-regulated.

[0018] Optionally, S4 is specifically:

[0019] S41. Calculate the load adjustment cost and pollution emission data of all adjustable coal-fired units;

[0020] S42, obtaining real-time load data of the adjustable coal-fired units and historical load data of the coal-fired units, determining the stable load average of the current adjustable coal-fired units in the historical peak-shaving process based on the historical load data, and calculating the difference between the real-time load and the stable load average of all adjustable coal-fired units;

[0021] S43, performing standardization processing on the load regulation cost, the pollution emission data, and the difference between the real-time load and the average value of the stable load, and assigning corresponding weights to the load regulation cost, the pollution emission data, and the difference between the real-time load and the average value of the stable load;

[0022] S44. Calculate the adjustment priority of all adjustable coal-fired units based on the load adjustment cost, pollution emission data, the difference between the real-time load and the stable load average, and the corresponding weights, sort all adjustable coal-fired units in descending order of adjustment priority, and obtain the load adjustment sequence of the adjustable coal-fired units.

[0023] Optionally, the load adjustment cost of all adjustable coal-fired units is calculated as follows:

[0024] C=C1+C2+C3

[0025] In the formula, C is the load regulation cost, C1 is the implementation cost of the mediation plan, C2 is the increased fuel cost, and C3 is the equipment loss cost.

[0026] Optionally, the pollution emission data of all adjustable coal-fired units are calculated as follows:

[0027] f=s i (P i )+n i (P i )

[0028]

[0029] In the formula, f is the pollutant emission, s is i (P i ) represents the SO2 emission of coal-fired unit i, n i (P i ) represents the NO of coal-fired unit i x Emissions, sα i , sβ i , sγ are the SO2 emission characteristic coefficients of coal-fired unit i, nα i , nβ i and nγ are the NO x Emission characteristic coefficient.

[0030] Optionally, S5 specifically comprises: determining the stable load extreme value of the current adjustable coal-fired unit during the historical peak-shaving process based on historical load data, taking the difference between the real-time load and the stable load extreme value corresponding to the adjustment instruction as the load adjustment capacity of the adjustable coal-fired unit, and allocating load adjustment targets to the adjustable coal-fired units in the order of the load adjustment sequence until the real-time load of the total coal-fired units reaches the target load.

[0031] It can be seen from the above technical scheme that compared with the prior art, the present invention provides a 20% load control method for a coal-fired unit, which has the following beneficial effects: the present invention can achieve rapid response of the coal-fired generating unit to changes in external load by adjusting the load of the coal-fired unit, while considering the cost of load adjustment to meet changes in external load demand, so that various types of energy resources can be used more reasonably and efficiently; the present invention takes into account the safety performance of the coal-fired unit when selecting to adjust the coal-fired unit, and takes into account the cost of adjustment, pollutant emissions and stable operation when determining the adjustment plan, thereby reducing the adjustment cost and pollutant emissions on the basis of achieving the deep peak regulation target, while ensuring the stable operation of the coal-fired unit as much as possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0033] Figure 1 This is a flow chart of the 20% load control method for a coal-fired unit of the present invention. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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 creative work are within the scope of protection of the present invention.

[0035] The embodiment of the present invention discloses a 20% load control method for a coal-fired unit, such as Figure 1 As shown, the following steps are included:

[0036] S1. Obtain the real-time load and target load of the current total coal-fired units, and determine the difference between the real-time load and the target load;

[0037] S2, determining the adjustment instruction of the total coal-fired unit load based on the difference between the real-time load and the target load;

[0038] S3, obtaining the operation data of the coal-fired units and determining the coal-fired units that can be load-regulated;

[0039] S4, determining a load adjustment sequence of the adjustable coal-fired unit based on the operation data of the adjustable coal-fired unit and the cost data of load adjustment;

[0040] S5. Determine the load regulation capabilities of all adjustable coal-fired units and allocate load regulation targets according to the load regulation sequences of the adjustable coal-fired units;

[0041] S6. Determine a response plan based on the load regulation target of the adjustable coal-fired units and perform load regulation according to the response plan, so that the load of the total coal-fired units is adjusted to the target load.

[0042] Furthermore, in S2, if the real-time load of the total coal-fired units is greater than the target load, the adjustment instruction is to reduce the load, and if the real-time load of the coal-fired units is less than the target load, the adjustment instruction is to increase the load.

[0043] Furthermore, S3 is specifically:

[0044] S31. Obtaining the operation safety index of the coal-fired unit;

[0045] S32. Determine the weight of each operational safety indicator according to its impact on the safety situation;

[0046] S33, calculating the safety evaluation score of the coal-fired unit based on the operation safety index and the corresponding weight;

[0047] S34. If the safety evaluation score of the coal-fired unit is greater than a preset threshold, it is determined as a coal-fired unit that can be load-regulated.

[0048] In the embodiments of the present invention, deep peak regulation may cause losses to coal-fired units and thus create safety hazards. For example, during the start-stop peak regulation process, the boiler air temperature and the heating surface wall temperature undergo large changes, which can easily cause metal stress fatigue, resulting in water-cooled wall cracking and heating surface leakage; frequent start-stop and load fluctuations of the unit can easily cause the oxide scale to fall off and block the boiler tube, resulting in overheating and tube bursting accidents; the frequent start-stop of auxiliary equipment has a certain impact on the reliability and stability of the equipment and increases the failure rate. Therefore, it is necessary to judge the operating safety indicators of the coal-fired unit to confirm whether it has the load regulation capability to ensure safety.

[0049] In the embodiment of the present invention, S32 is specifically:

[0050] The impact of each operation safety indicator on the safety situation is divided into multiple safety areas, including personal safety, equipment safety and environmental safety. The impact degree of each area is divided into multiple levels, namely, extremely serious hazards, major hazards, general hazards, minor hazards and no hazards. According to the actual value of the operation safety indicator of the current coal-fired unit, the impact degree is judged. For example, in the embodiment of the present invention, an operation safety indicator may have the following impact degrees on personal safety, equipment safety and environmental safety: general hazard, general hazard and no hazard. The five levels and three safety areas are all preset with weight values. Then the impact degree of this operation safety indicator is:

[0051] j=a1·b 13 +a2·b 23 +a3·b 35

[0052] In the formula, j is the impact degree of this operation safety index, a1 represents the personal safety weight value, b 13 represents the general hazard weight value for personal safety, a2 represents the equipment safety weight value, b 13 represents the general hazard weight value of equipment safety, a3 represents the environmental safety weight value, b 13 Indicates the weight value of environmental safety and no hazard;

[0053] In the embodiment of the present invention, a total of n operation safety indicators are included, and the weight values ​​are respectively:

[0054]

[0055] In the formula, w i represents the weight of the ith operation safety index, and represents the impact value of the ith operation safety index;

[0056] S33 is specifically:

[0057] j=s1·w1+s2·w2+...+s n ·w n

[0058] Where s1 represents the first operational safety index.

[0059] Furthermore, S4 is specifically:

[0060] S41. Calculate the load adjustment cost and pollution emission data of all adjustable coal-fired units;

[0061] S42, obtaining real-time load data of the adjustable coal-fired units and historical load data of the coal-fired units, determining the stable load average of the current adjustable coal-fired units in the historical peak-shaving process based on the historical load data, and calculating the difference between the real-time load and the stable load average of all adjustable coal-fired units;

[0062] S43, performing standardization processing on the load regulation cost, the pollution emission data, and the difference between the real-time load and the average value of the stable load, and assigning corresponding weights to the load regulation cost, the pollution emission data, and the difference between the real-time load and the average value of the stable load;

[0063] S44. Calculate the adjustment priority of all adjustable coal-fired units based on the load adjustment cost, pollution emission data, the difference between the real-time load and the stable load average, and the corresponding weights, sort all adjustable coal-fired units in descending order of adjustment priority, and obtain the load adjustment sequence of the adjustable coal-fired units.

[0064] Furthermore, the load regulation cost of all adjustable coal-fired units is calculated as follows:

[0065] C=C1+C2+C3

[0066] In the formula, C is the load regulation cost, C1 is the implementation cost of the mediation plan, C2 is the increased fuel cost, and C3 is the equipment loss cost.

[0067] Furthermore, the pollution emission data of all adjustable coal-fired units are calculated as follows:

[0068] f=s i (P i )+n i (P i )

[0069]

[0070] In the formula, f is the pollutant emission, s is i (P i ) represents the SO2 emission of coal-fired unit i, ni (P i ) represents the NO of coal-fired unit i x Emissions, sα i , sβ i , sγ are the SO2 emission characteristic coefficients of coal-fired unit i, nα i , nβ i and nγ are the NO x Emission characteristic coefficient.

[0071] Furthermore, S5 is specifically as follows: based on the historical load data, the stable load extreme value of the current adjustable coal-fired unit in the historical peak-shaving process is determined, and the difference between the real-time load and the stable load extreme value corresponding to the adjustment instruction is used as the load adjustment capacity of the adjustable coal-fired unit, and the load adjustment targets are allocated to the adjustable coal-fired units in the order of the load adjustment sequence until the real-time load of the total coal-fired units reaches the target load.

[0072] In the embodiment of the present invention, the response scheme in S6 adopts the existing adjustment method.

[0073] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0074] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A 20% load control method for a coal-fired unit, characterized in that: The following steps are involved: S1. Obtain the real-time load and target load of the current total coal-fired units, and determine the difference between the real-time load and the target load; S2, determining the adjustment instruction of the total coal-fired unit load based on the difference between the real-time load and the target load; S3, obtaining the operation data of the coal-fired units and determining the coal-fired units that can be load-regulated; S4, determining a load adjustment sequence of the adjustable coal-fired unit based on the operation data of the adjustable coal-fired unit and the cost data of load adjustment; S5. Determine the load regulation capabilities of all adjustable coal-fired units and allocate load regulation targets according to the load regulation sequences of the adjustable coal-fired units; S6. Determine a response plan based on the load regulation target of the adjustable coal-fired units and perform load regulation according to the response plan, so that the load of the total coal-fired units is adjusted to the target load.

2. A 20% load control method for a coal-fired unit according to claim 1, characterized in that: In S2, if the real-time load of the total coal-fired units is greater than the target load, the adjustment instruction is to reduce the load; if the real-time load of the total coal-fired units is less than the target load, the adjustment instruction is to increase the load.

3. A 20% load control method for a coal-fired unit according to claim 1, characterized in that: S3 is specifically: S31. Obtaining the operation safety index of the coal-fired unit; S32. Determine the weight of each operational safety indicator according to its impact on the safety situation; S33, calculating the safety evaluation score of the coal-fired unit based on the operation safety index and the corresponding weight; S34. If the safety evaluation score of the coal-fired unit is greater than a preset threshold, it is determined as a coal-fired unit that can be load-regulated.

4. A 20% load control method for a coal-fired unit according to claim 1, characterized in that: S4 is specifically: S41. Calculate the load adjustment cost and pollution emission data of all adjustable coal-fired units; S42, obtaining real-time load data of the adjustable coal-fired units and historical load data of the coal-fired units, determining the stable load average of the current adjustable coal-fired units in the historical peak-shaving process based on the historical load data, and calculating the difference between the real-time load and the stable load average of all adjustable coal-fired units; S43, performing standardization processing on the load regulation cost, the pollution emission data, and the difference between the real-time load and the average value of the stable load, and assigning corresponding weights to the load regulation cost, the pollution emission data, and the difference between the real-time load and the average value of the stable load; S44. Calculate the adjustment priority of all adjustable coal-fired units based on the load adjustment cost, pollution emission data, the difference between the real-time load and the stable load average, and the corresponding weights, sort all adjustable coal-fired units in descending order of adjustment priority, and obtain the load adjustment sequence of the adjustable coal-fired units.

5. A 20% load control method for a coal-fired unit according to claim 4, characterized in that: The load regulation cost of all adjustable coal-fired units is calculated as follows: C=C1+C2+C3 In the formula, C is the load regulation cost, C1 is the implementation cost of the mediation plan, C2 is the increased fuel cost, and C3 is the equipment loss cost.

6. A 20% load control method for a coal-fired unit according to claim 4, characterized in that: The specific calculation of the pollution emission data of all adjustable coal-fired units is as follows: f=s i (P i )+n i (P i ) In the formula, f is the pollutant emission, s is i (P i ) represents the SO2 emission of coal-fired unit i, n i (P i ) represents the NO of coal-fired unit i x Emissions, sα i , sβ i , sγ are the SO2 emission characteristic coefficients of coal-fired unit i, nα i , nβ i and nγ are the NO x Emission characteristic coefficient.

7. A 20% load control method for a coal-fired unit according to claim 4, characterized in that: S5 is specifically as follows: based on the historical load data, the stable load extreme value of the current adjustable coal-fired unit in the historical peak regulation process is determined, and the difference between the real-time load and the stable load extreme value corresponding to the regulation instruction is used as the load regulation capacity of the adjustable coal-fired unit. The load regulation targets are allocated to the adjustable coal-fired units in the order of the load regulation sequence until the real-time load of the total coal-fired units reaches the target load.

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