Burner Pulse Combustion Control Method Based on Weighted Round Robin Scheduling

Abstract

The present invention discloses a burner pulse combustion control system and a control method based on weighted round-robin scheduling. The control method includes: the heating furnace PID adjustment unit calculates the power output ratio Y of the heating furnace according to the furnace temperature set value required for workpiece heating and the furnace temperature measurement value fed back by the burner group p ; the burner weighted round-robin scheduling control unit determines the combustion cycle period T, the burner reference opening duration T p , and the burner reference closing duration T on based on the power output ratio Y of the heating furnace off and the burner parameters of the burner group, compares the power output ratio Y p with the weight restart threshold Y r . If Y p < Y r , weight control is enabled, and the actual opening duration T i of each burner in the burner group within the combustion cycle period T is controlled accordingly p . If Y > Y r , weight control is not enabled, and the actual opening duration T i of each burner in the burner group within the combustion cycle period T is controlled accordingly. The present invention ensures the furnace temperature uniformity in the temperature control area and improves the workpiece heating quality

Description

Technical Field

[0001] The present invention belongs to the technical field of heating furnace temperature control, and particularly relates to a burner pulse combustion control system and a control method based on weighted round-robin scheduling. Background Art

[0002] The ideal goal of a heating furnace is to obtain good workpiece quality while consuming less energy. To achieve the above goal, a reasonable heating furnace temperature control strategy needs to be adopted. Existing heating furnace temperature control methods include proportional control, double-cross limit control, etc. However, with the improvement of the workpiece heating process requirements, these control methods increase the working load of the heating furnace burners, reduce the service life of the burners, and have low heat transfer efficiency in the heating furnace, resulting in unsatisfactory temperature control effects.

[0003] Currently, most heating furnaces adopt burner pulse combustion control technology. In this control technology, the switch valve is preset with the best air-fuel ratio, and the burners are controlled by the pulse timing control ignition method, which is beneficial to achieving the best combustion and improving the combustion efficiency. However, in the actual combustion control process, there is a disadvantage of a long control reaction cycle, and it is impossible to quickly and effectively adjust and control in real time according to the current furnace temperature condition. The heating furnace temperature control result is difficult to meet the requirements; and due to different combustion environments of different burners, serious heat loss occurs near the inlet and outlet of the heating furnace, so the furnace temperature uniformity in the temperature control area is poor, the overall furnace temperature change curve fluctuates greatly, reducing the workpiece heating quality and increasing the energy consumption of the heating furnace. Summary of the Invention

[0004] To solve some or all of the above technical problems existing in the prior art, the present invention provides a burner pulse combustion control system based on weighted round-robin scheduling and a burner pulse combustion control method based on weighted round-robin scheduling.

[0005] In one aspect of the present invention, the provided burner pulse combustion control system based on weighted round-robin scheduling includes a heating furnace PID adjustment unit, a burner group, and a burner weighted round-robin scheduling control unit. The heating furnace PID adjustment unit obtains the power output ratio of the heating furnace according to the furnace temperature set value required for workpiece heating and the furnace temperature measurement value fed back by the burner group. The burner weighted round-robin scheduling control unit controls the actual opening duration and opening pulse timing of each burner in the burner group through weight allocation and round-robin scheduling based on the power output ratio and the burner parameters of the burner group.

[0006] In another aspect of the present invention, the provided burner pulse combustion control method based on weighted round-robin scheduling includes the following steps:

[0007] S1. The heating furnace PID adjustment unit calculates the power output ratio Y of the heating furnace based on the set furnace temperature required for workpiece heating and the measured furnace temperature feedback from the burner group. p ;

[0008] S2. The burner weight polling scheduling control unit determines the combustion cycle period T, the burner reference opening duration T p and the burner reference closing duration T on based on the power output ratio Y of the heating furnace off and the burner parameters of the burner group, and controls the actual opening duration Ti of each burner S 1 in the burner group S = {S 2 , S N} during the combustion cycle period T, where i = 1, 2,..., N. The burner parameters include the number of burners N in the burner group S = {S i , S 1 ,..., S 2}, the minimum opening duration T N of the burner within one combustion cycle period T, the maximum opening duration T onmin of the burner within one combustion cycle period T, and the minimum closing duration T onmax of the burner within one combustion cycle period T. offmin The specific steps of step S2 include the following sub-steps:

[0009] S21. Compare the power output ratio Y p with the weight restart threshold Yr, and decide whether to enable weight control according to the comparison result. The weight restart threshold where w max is the maximum output difference coefficient of each burner S 1 in the burner group S = {S 2 , S N}; i ;

[0010] S22. If Y p < Y r , enable weight control, and control the actual opening duration T 1 of each burner S 2 in the burner group S = {S N , S i} during the combustion cycle period T as follows: Set the burner reference opening duration to T i = T on = T onmin , set the burner reference closing duration to T off = T - T on , and the combustion cycle period where w iFor the weights of each burner S in the burner group S = {S 1 , S 2 , …, S N}; in the burner group S = {S i , S 1 , S 2 , …, S N}, where the weight of each burner S i is w i , in the burner group S = {S 1 , S 2 , …, S N}, set the weight w a of the burner S a in the furnace door area of the heating furnace to 1 < w a ≤ w max , set the weight w 1 of the burner S 2 in the exhaust port area of the heating furnace in the burner group S = {S N , S b} to 1 < w b ≤ w b ≤ w max , and keep the weights w 1 of the other burners S 2 in the burner group S = {S N , S j , …, S j} all as 1, where 1 ≤ a ≤ N, 1 ≤ b ≤ N, j = 1, 2…, N and j ≠ a ≠ b; in the burner group S = {S 1 , S 2 , …, S N}, control the actual opening duration T a of the burner S a in the furnace door area of the heating furnace during the combustion cycle T to T a = w a × T on = w a × T onmin , control the actual opening duration T 1 of the burner S 2 in the exhaust port area of the heating furnace in the burner group S = {S N , S b} during the combustion cycle T to T b = w b × T b = w on × T b × T onmin , in the burner group S = {S 1 , S 2 , …, S N} other burners S j The actual on-time T within the combustion cycle period T j Control to T j = w j ×T on = T on = T onmin ;

[0011] S23. If Y p > Y r , do not enable weight control. The weight w of each burner S in the burner group S = {S 1 , S 2 ,..., S N} is 1, and the actual on-time T of each burner S in the burner group S = {S i is controlled as follows: Compare the power output ratio Y i with the burner cycle period conversion threshold Y 1 , S 2 ,..., S N} within the combustion cycle period T i : Compare the power output ratio Y i with the burner cycle period conversion threshold Y p . The burner cycle period conversion threshold s If Y > Y p > Y s , the combustion cycle period T is converted to the burner reference off-time T off and the burner reference on-time T on are respectively set to: T off = T offmin , T on = T - T off , and the actual on-time T of each burner S in the burner group S = {S 1 , S 2 , …, S N} within the combustion cycle period T i is all i If Y p < Y s < Y, the combustion cycle period T is converted to the burner reference on-time T on and the burner reference off-time T off are respectively set to: T on = T onmin , T off = T - T on , and the actual on-time T of each burner S in the burner group S = {S 1 , S 2 , …, S Neach burner S in i the actual on - time T within the combustion cycle period T i is all T i = w i ×T on = T on = T onmin .

[0012] Furthermore, in the above - mentioned burner pulse combustion control method based on weighted round - robin scheduling, the burner group S = {S 1 , S 2 , …, S N}, the number of burners N = 10. The minimum on - time T onmin of each burner within a combustion cycle period T is 10s, the maximum on - time T onmax is 297s, the minimum off - time T offmin is 3s, and the maximum output difference coefficient of each burner is 1.5 - 2.0.

[0013] Furthermore, in the above - mentioned burner pulse combustion control method based on weighted round - robin scheduling, it also includes controlling the on - pulse timing of each burner in the burner group through round - robin scheduling, specifically including:

[0014] Set the minimum on - wait T 1 of each burner S 2 in the burner group S = {S N}; i d 1 ;

[0015] Set the number of ignited burners in the burner group S = {S 1 , S 2 , …, S N} to be K, and the waiting time of the (K + 1) - th burner S k+1 is T w , where K = 1, 2 …, N - 1;

[0016] When T w > T d and , the (K + 1) - th burner S k+1 is ignited.

[0017] The burner pulse combustion control system and control method based on weighted round - robin scheduling of the present invention have the following advantages and

[0018] beneficial effects:

[0019] The burner pulse combustion control system and control method based on weighted round-robin scheduling of the present invention perform burner pulse combustion control through a round-robin scheduling algorithm and a weighting algorithm, thereby controlling the opening pulse timing, combustion time, and heat output weight of burners located in different areas of the heating furnace, ensuring effective adjustment according to the current furnace temperature condition, greatly improving the level of pressure fluctuation in the pulse jet region, effectively promoting gas circulation in the furnace, regulating the furnace atmosphere, and improving heat transfer and temperature uniformity in the furnace, thereby optimizing the temperature control of the heating furnace, obtaining a better overall furnace temperature change curve, making the overall temperature in the furnace balanced, ensuring the furnace temperature uniformity in the temperature control area, improving the heating quality of workpieces, reducing the loss of the heating furnace, and saving energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only for further understanding of the embodiments of the present invention and constitute a part of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings. In the drawings:

[0021] Figure 1 It is a schematic block diagram of the composition principle of the burner pulse combustion control system based on weighted round-robin scheduling of the present invention;

[0022] Figure 2 It is a schematic diagram of the pulse timing of burner opening when the power output ratio Y p = 99% is controlled by the burner pulse combustion control method based on weighted round-robin scheduling of the present invention;

[0023] Figure 3 It is a schematic diagram of the pulse timing of burner opening when the power output ratio Y p = 50% is controlled by the burner pulse combustion control method based on weighted round-robin scheduling of the present invention;

[0024] Figure 4 It is a schematic diagram of the pulse timing of burner opening when the power output ratio Y p = 30% is controlled by the burner pulse combustion control method based on weighted round-robin scheduling of the present invention;

[0025] Figure 5 It is a schematic diagram of the pulse timing of burner opening when the power output ratio Y p = 30% and no weight distribution control is applied to the heat output of each burner as a comparative example; DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] To make the objectives, technical solutions and advantages of the present invention more clear, the following will clearly and completely describe the technical solutions of the present invention in combination with specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative work fall within the scope of protection of the present invention.

[0027] The burner pulse combustion control system and control method based on weighted round-robin scheduling of the present invention perform burner pulse combustion control through a weight algorithm and a round-robin scheduling algorithm, realizing the control of the combustion time and the opening pulse timing of the burner, and optimizing the temperature control of the heating furnace.

[0028] As Figure 1 shown, the burner pulse combustion control system based on weighted round-robin scheduling of the present invention includes: a heating furnace PID adjustment unit, a burner group, and a burner weight round-robin scheduling control unit. The heating furnace PID adjustment unit obtains the power output ratio of the heating furnace according to the furnace temperature set value required for workpiece heating and the furnace temperature measurement value fed back by the burner group. The burner weight round-robin scheduling control unit controls the combustion time (i.e., the actual opening duration) and the opening pulse timing of each burner in the burner group through weight allocation and round-robin scheduling based on the power output ratio of the heating furnace and the burner parameters of the burner group, thereby realizing the real-time dynamic control of the heating furnace temperature.

[0029] It should be noted that the "heating furnace PID adjustment unit" herein is a conventional technology in the art. It forms a control quantity by linearly combining the proportion, integral, and differential of the deviation according to the deviation between the set value and the measurement value (i.e., the actual output value), and adjusts and controls the controlled object. Details thereof will not be elaborated herein.

[0030] The burner pulse combustion control method based on weighted round-robin scheduling of the present invention is implemented by using the above-mentioned burner pulse combustion control system based on weighted round-robin scheduling, and specifically includes the following steps:

[0031] S1. The heating furnace PID adjustment unit calculates the power output ratio Y of the heating furnace according to the furnace temperature set value required for workpiece heating and the furnace temperature measurement value fed back by the burner group p ;

[0032] S2. The burner weight round-robin scheduling control unit determines the combustion cycle period T, the burner reference opening duration T p and the burner reference closing duration T on based on the power output ratio Y of the heating furnace off and the burner parameters of the burner group, and controls the burner group S = {S 1 , S 2 , …, S N} each burner S i The actual opening duration T within the combustion cycle period T i , i = 1, 2…, N, where the burner parameters include the number N of burners in the burner group S = {S 1 , S 2 , …, S N}, the minimum opening duration T of the burner within one combustion cycle period T onmin , the maximum opening duration T of the burner within one combustion cycle period T onmax , the minimum closing duration T of the burner within one combustion cycle period T offmin , Step S2 specifically includes the following sub-steps:

[0033] S21. Compare the power output ratio Y p with the weight restart threshold Y r to decide whether to enable weight control according to the comparison result. The weight restart threshold where, w max is the maximum output difference coefficient of each burner S in the burner group S = {S 1 , S 2 ,..., S N}. For a given heating furnace, w i is known and takes a value of 1.5 to 2.0; max

[0034] S22. If Y p < Y r , enable weight control and control the actual opening duration T of each burner S in the burner group S = {S 1 , S 2 ,..., S N} within the combustion cycle period T as follows: The reference opening duration of the burner is set to T i = T i , the reference closing duration of the burner is set to T on = T - T onmin , the combustion cycle off = T - T on , where w i is the weight value of each burner S in the burner group S = {S 1 , S 2 ,..., S N}; in the weight values w i of each burner S in the burner group S = {S 1 , S 2 ,..., S N}, the weight values of each burner S in the burner group S = {S N} are w i , and in w i , the burner group S = {S 1 , S 2, …, S N} the burner S in the area of the furnace door of the heating furnace a with the weight value w a is set such that 1 < w a ≤ w max , and for the burner group S = {S 1 , S 2 , …, S N} the burner S in the area of the smoke outlet of the heating furnace b with the weight value w b is set such that 1 < w b ≤ w max , and for the burner group S = {S 1 , S 2 ,..., S N} all the other burners S j with the weight value w j are maintained at 1, where 1 ≤ a ≤ N, 1 ≤ b ≤ N, j = 1, 2 …, N and j ≠ a ≠ b; the burner group S = {S 1 , S 2 ,..., S N} the burner S in the area of the furnace door of the heating furnace a the actual opening duration T a during the combustion cycle T is controlled to be T a = w a × T on = w a × T onmin , for the burner group S = {S 1 , S 2 ,..., S N} the burner S in the area of the smoke outlet of the heating furnace b the actual opening duration T b during the combustion cycle T is controlled to be T b = w b × T on = w b × T onmin , for the burner group S = {S 1 , S 2 ,..., S N} all the other burners S j the actual opening duration T j during the combustion cycle T is controlled to be T j = w j × T on = T on = T onmin ;

[0035] S23. If Y p > Y r, without enabling weight control, for each burner S in the burner group S = {S 1 , S 2 ,..., S N}, the weight value w i of each burner is 1, and the actual on-time duration T i of each burner S in the burner group S = {S 1 , S 2 ,..., S N} during the combustion cycle period T is controlled in the following manner: Compare the power output ratio Y i with the burner cycle period conversion threshold Y i . The burner cycle period conversion threshold p If Y s > Y , the combustion cycle period T is converted to p the burner reference off-time duration T s and the burner reference on-time duration T are respectively set as: T off = T on , T off = T - T offmin , and the actual on-time duration T on of each burner S in the burner group S = {S off , S 1 , S 2 , …, S N} during the combustion cycle period T is i all i If Y < Y r < Y p < Y s , the combustion cycle period T is converted to the burner reference on-time duration T on and the burner reference off-time duration T off are respectively set as: T on = T onmin , T off = T - T on , and the actual on-time duration T 1 , S 2 , …, S N} of each burner S in the burner group S i during the combustion cycle period T is i all T i = w i × T on = T on = T onmin .

[0036] It goes without saying that for a given heating furnace, the number of burners N is known and a fixed value, and the minimum on-time duration of the burner Tonmin 、The maximum opening duration T of the burner onmax 、The minimum closing duration T of the burner offmin are known and fixed values. For example, as a specific embodiment, for a given heating furnace, the number of burners N = 10, that is, the burner group of the heating furnace includes 10 burners distributed in all heating areas of the heating furnace. The minimum opening duration T of each burner in a combustion cycle T onmin = 10s, the maximum opening duration T onmax = 297s, and the minimum closing duration T offmin = 3s.

[0037] Furthermore, the burner pulse combustion control method based on weighted round-robin scheduling of the present invention further includes: controlling the opening pulse timing of each burner in the burner group through round-robin scheduling, specifically including: setting the minimum opening waiting time T of each burner S in the burner group S = {S 1 , S 2 ,..., S N}, for example, T i can be set to 1s - 3s; setting the number of ignited burners in the burner group S = {S d , S d ,..., S 1 , S 2 ,..., S N} as K, and the waiting time of the (K + 1)-th burner S k+1 is T w , where K = 1, 2…, N - 1; when T w > T d and , the (K + 1)-th burner S k+1 is ignited.

[0038] By the above steps of controlling the opening pulse timing of each burner in the burner group, each burner in the burner group can be sequentially opened, which can avoid the impact on the pressure of the natural gas pipeline and the combustion-supporting air pipeline of the pulse burner caused by multiple burners in the same area being enabled simultaneously, and can further ensure the uniformity of the furnace temperature in the temperature control area.

[0039] The following combines specific embodiments to detail the burner pulse combustion control method based on weighted round-robin scheduling of the present invention.

[0040] Embodiment 1

[0041] The burner pulse combustion control method based on weighted round-robin scheduling in Embodiment 1 of the present invention includes:

[0042] Step 1: The PID adjustment unit of the heating furnace calculates the power output ratio Y of the heating furnace according to the furnace temperature set value required for workpiece heating and the furnace temperature measurement value feedback by the burner groupp =99%;

[0043] Step 2: The burner weight polling scheduling control unit is based on the power output ratio Y of the heating furnace p And the burner parameters of the burner group, determine the combustion cycle T, burner opening time T on and burner closing time T off , and control the burner group S = {S 1 , S 2 , ..., S N}Each burner S i The actual opening time T within the combustion cycle T i , where the burner parameters are: burner group S = {S 1 , S 2 , …, S N The number of burners in the burner is N = 10, and the minimum opening time of each burner in a combustion cycle T is T onmin =10s, maximum opening time T onmax =297s, minimum closing time T offmin =3s, the second step specifically includes:

[0044] The power output ratio Y p Enable threshold with weight Y r For comparison, the burner group S = {S 1 , S 2 , ..., S N}Each burner S i The maximum output difference coefficient w max If the value is 2, the weight enables the threshold Because Y p >Y r , weight control is not enabled, burner group S = {S 1 , S 2 , ..., S N}Each burner S i The weight w i All are 1;

[0045] The power output ratio Y p Calculate the switching point Y with the cycle period s The comparison is made, where the cycle period calculates the switching point Because Y p >Y s , so the combustion cycle Burner reference closing time T off =T offmin =3s, burner reference opening time T on =TT off= 300s - 3s = 297s. The burner group S = {S 1 , S 2 , …, S N}. The actual on - time T i of each burner S i in the 300s combustion cycle period T i is all T i = w on × T

[0046] Figure 2 shows the pulse timing diagram of the burner opening when the power output ratio Y p = 99% is controlled by the burner pulse combustion control method based on weighted round - robin scheduling in Embodiment 1. It can be seen that each burner in the heating furnace burner group burns in pulses according to the actual on - time of 297s (equal to the burner reference on - time) in each 300s combustion cycle period, and then closes according to the actual off - time of 3s (equal to the burner reference off - time) of the burner, and then enters the next 300s combustion cycle period. Thus, the control of the combustion time and the opening pulse timing of the burner is realized, and the temperature control of the heating furnace is optimized.

[0047] Embodiment 2

[0048] The burner pulse combustion control method based on weighted round - robin scheduling in Embodiment 2 of the present invention includes the following steps:

[0049] Step 1: The heating furnace PID adjustment unit calculates the power output ratio of the heating furnace as Y p = 50% according to the furnace temperature set value required for workpiece heating and the furnace temperature measurement value fed back by the burner group.

[0050] Step 2: The burner weighted round - robin scheduling control unit determines the combustion cycle period T, the burner on - time T p and the burner off - time T on based on the power output ratio Y off of the heating furnace and the burner parameters of the burner group, and controls the actual on - time T 1 of each burner S 2 in the burner group S = {S N}, S i in the combustion cycle period T i , where the burner parameters are: the number of burners N in the burner group S = {S 1 , S 2 , …, S N} is 10, and the minimum on - time T onmin of each burner in one combustion cycle period T is 10s, the maximum on - time T onmax=297s, minimum closing time T offmin =3s, the second step specifically includes:

[0051] The power output ratio Y p Enable threshold with weight Y r For comparison, the burner group S = {S 1 , S 2 , ..., S N Each burner S i The maximum output difference coefficient w max If the value is 2, the weight is enabled. Because Y p >Y r , weight control is not enabled, burner group S = {S 1 , S 2 , ..., S N Each burner S i The weight w i All are 1;

[0052] The power output ratio Y p Calculate the switching point Y with the cycle period s The comparison is made, where the cycle period calculates the switching point Because Y p <Y s , so the combustion cycle Burner standard opening time T on =T onmin =10s, burner reference closing time T off =TT on =20s-10s=10s. Burner group S={S 1 , S 2 , ..., S N Each burner S i The actual opening time T within the 20s combustion cycle T i All T i =w i ×T on =1×10=10s.

[0053] Figure 3 The burner pulse combustion control method based on weighted polling scheduling of Example 2 is shown as follows: p=50% of the pulse sequence diagram of the burner opening, it can be seen that each burner in the heating furnace burner group pulses according to the actual opening time of 10s (equal to the burner reference opening time) in each 20s combustion cycle, and then closes according to the actual closing time of the burner of 10s (equal to the burner reference closing time), and then enters the next 20s combustion cycle. In this way, the control of the burner's combustion time and the opening pulse sequence is realized, and the heating furnace temperature control is optimized.

[0054] Example 3

[0055] The burner pulse combustion control method based on weighted round-robin scheduling of embodiment 3 of the present invention comprises the following steps:

[0056] Step 1: The heating furnace PID adjustment unit calculates the power output ratio of the heating furnace to be Y according to the furnace temperature setting value required for heating the workpiece and the furnace temperature measurement value fed back by the burner group. p =30%.

[0057] Step 2: The burner weight polling scheduling control unit is based on the power output ratio Y of the heating furnace p And the burner parameters of the burner group, determine the combustion cycle T, the burner reference opening time T on and burner reference closing time T off , and control the burner group S = {S 1 , S 2 , …, S N}Each burner S i The actual opening time Ti in the combustion cycle T, i = 1, 2 ..., N, where the burner parameters are: burner group S = {S 1 , S 2 , ..., S N The number of burners in the burner is N = 10, and the minimum opening time of each burner in a combustion cycle T is T onmin =10s, maximum opening time T onmax =297s, minimum closing time T offmin =3s, the second step specifically includes:

[0058] The power output ratio Y p Enable threshold with weight Y r For comparison, the burner group S = {S 1 , S 2 , ..., S N}Each burner S i The maximum output difference coefficient w max If the value is 2, the weight enables the threshold Because Y p <Y r, enable weight control, and control the burner group S as follows: 1 , S 2 , ..., S N Each burner S i The actual opening time T within the combustion cycle T i :

[0059] The burner base opening time is set to T on =T onmin , the burner reference closing time is set to T off =TT on , combustion cycle where w i For the burner group S = {S 1 , S 2 , …, S N Each burner S i The weight of the burner group S = {S 1 , S 2 , ..., S N Each burner S i The weight is w i In the burner group S = {S 1 , S 2 , ..., S N Burner S in the heating furnace door area 1 The weight w 1 Adjust to 2, set the burner group S = {S 1 , S 2 , ..., S N The burner S in the exhaust port area of ​​the heating furnace 2 The weight w 2 Adjust to 2, and set the burner group S = {S 1 , S 2 , ..., S N}Except burner S 1 and burner S 2 Other burners except S i The weight w i All remain at 1, combustion cycle

[0060] Burner group S = {S 1 , S 2 , ..., S N Burner S in the heating furnace door area 1 The actual opening time T within the 40s combustion cycle T 1 T 1 =w 1 ×T on =2×Tonmin = 20 s, the burner group S = {S 1 , S 2 ,..., S N} in the burners S in the area of the heating furnace flue gas outlet 2 The actual opening duration T 2 in the 40 s combustion cycle T 2 is T 2 = w on × T onmim = 2 × T 1 , S 2 ,..., S N} except for burners S 1 and burner S 2 of the other burners S i The actual opening duration T i in the 40 s combustion cycle T i is T i = w on × T onmim = 1 × T

[0061] Figure 4 shows the pulse timing diagram of the burner opening when the power output ratio Y p = 30% is controlled by the burner pulse combustion control method based on weighted round-robin scheduling in Embodiment 3. It can be seen that the burners in the heating furnace door area and the burners in the heating furnace flue gas outlet area of the heating furnace burner group pulse combust at an actual opening duration of 20 s (longer than the burner reference opening duration) in each 40 s combustion cycle, and then close at an actual closing duration of 20 s (shorter than the burner reference closing duration) of the burner. The other burners in the heating furnace burner group in the area other than the furnace door and flue gas outlet area pulse combust at an actual opening duration of 10 s (equal to the burner reference opening duration) in each 40 s combustion cycle, and then close at an actual closing duration of 30 s (equal to the burner reference closing duration) of the burner, and then enter the next 40 s combustion cycle. Thus, the combustion time and opening pulse timing of the burner are controlled, and the temperature control of the heating furnace is optimized.

[0062] As a comparative example, if no weight distribution is performed on the heating furnace door area and the flue gas outlet area, and the burners are controlled only by round-robin scheduling, that is, the weight w 1 of each burner S 2 in the burner group S = {S N ,..., S i} i is 1 for all, for the power output ratio Y p and the cycle period calculation conversion point Y sCompare, where the cycle period calculates the conversion point Due to Y p <Y s , the combustion cycle period The standard opening duration T of the burner on =T onmin =10s, the reference closing duration T of the burner off =T - T on =33.3s - 10s=23.3s. As Figure 5 shown, each burner in the burner group of the heating furnace pulses and burns according to the actual opening duration of 10s (equal to the reference opening duration of the burner) within each 33.3s combustion cycle period, and then closes according to the actual closing duration of 23.3s of the burner (equal to the reference closing duration of the burner), and then enters the next 33.3s combustion cycle period. However, during the actual operation of the heating furnace, due to serious heat loss in the area near the furnace door or the smoke exhaust port, without weight control of the heat output of the burners at the furnace door or the smoke exhaust port, it is impossible to make the burners in this area output more heat than the burners in other areas, which will result in poor furnace temperature uniformity in the temperature control area of the heating furnace.

[0063] In summary, the burner pulse combustion control system and control method based on weighted round-robin scheduling of the present invention perform burner pulse combustion control through the round-robin scheduling algorithm and the weight algorithm, thereby controlling the opening pulse timing, combustion time, and heat output weight of the burners located in different areas of the heating furnace, ensuring effective adjustment according to the current furnace temperature condition, greatly improving the level of pressure fluctuation in the pulse jet area, effectively promoting gas circulation in the furnace, adjusting the furnace atmosphere, improving heat transfer and temperature uniformity in the furnace, thereby optimizing the temperature control of the heating furnace, obtaining a better overall furnace temperature change curve, making the overall temperature in the furnace balanced, ensuring furnace temperature uniformity in the temperature control area, improving the heating quality of workpieces, reducing the burnout of the heating furnace, and saving energy.

[0064] It should be noted that in this article, unless otherwise clearly stipulated and defined, the term "connection" or its synonyms should be understood in a broad sense. For example, "connection" can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meaning of the above terms in the present invention can be understood according to specific circumstances. Moreover, expressions such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. At the same time, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not explicitly listed, or further includes elements inherent to such process, method, article or device.

[0065] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A burner pulse combustion control method based on weighted round-robin scheduling, which is implemented by a burner pulse combustion control system based on weighted round-robin scheduling. The burner pulse combustion control system based on weighted round-robin scheduling includes a heating furnace PID adjustment unit, a burner group, and a burner weight round-robin scheduling control unit. The heating furnace PID adjustment unit obtains the power output ratio of the heating furnace according to the furnace temperature set value required for workpiece heating and the furnace temperature measurement value fed back by the burner group. The burner weight round-robin scheduling control unit controls the actual opening duration and opening pulse timing of each burner in the burner group through weight allocation and round-robin scheduling based on the power output ratio and the burner parameters of the burner group. Characterized in that, The burner pulse combustion control method based on weighted round-robin scheduling includes the following steps: S1. The heating furnace PID adjustment unit calculates the power output ratio Y of the heating furnace based on the furnace temperature set value required for workpiece heating and the furnace temperature measurement value feedback by the burner group. p ; S2. The burner weight polling and scheduling control unit determines the combustion cycle period T, the burner reference on-time T p and the burner reference off-time T on based on the power output ratio Y of the heating furnace off and the burner parameters of the burner group, and controls the actual on-time T 1 of each burner S 2 in the burner group S = {S N}, S i during the combustion cycle period T, where i = 1, 2,..., N. The burner parameters include the number N of burners in the burner group S = {S i}, S 1 , S 2 ,..., S N}, the minimum on-time T onmin of the burners during one combustion cycle period T, the maximum on-time T onmax of the burners during one combustion cycle period T, and the minimum off-time T offmin of the burners during one combustion cycle period T. The specific steps of step S2 are as follows: S21, the power output ratio Y p Enable threshold with weight Y r Compare and decide whether to enable weight control according to the comparison result. The weight enabling threshold Among them, w max For the burner group S = {S 1 ,S 2 ,…,S N }Each burner S i The maximum output difference coefficient is 1.5 to 2.0; S22, if Y p <Y r , enable weight control, and control the burner group S as follows: 1 ,S 2 ,…,S N }Each burner S i The actual opening time T within the combustion cycle T i :The burner base opening time is set to T on =T onmin , the burner reference closing time is set to T off =TT on , combustion cycle where w i For the burner group S = {S 1 ,S 2 ,…,S N }Each burner S i The weight of burner group S = {S 1 ,S 2 ,…,S N Each burner S i The weight is w i In the burner group S = {S 1 ,S 2 ,…,S N Burner S in the heating furnace door area a The weight w a Set to 1 <w a ≤w max , the burner group S = {S 1 ,S 2 ,…,S N The burner S in the exhaust port area of ​​the heating furnace b The weight w b Set to 1 <w b ≤w max , and burner group S = {S 1 ,S 2 ,…,S N Other burners S j The weight w j All remain at 1, where 1≤a≤N, 1≤b≤N, j=1,2…,N and j≠a≠b; burner group S={S 1 ,S 2 ,…,S N Burner S in the heating furnace door area a The actual opening time T within the combustion cycle T a Control is T a =w a ×T on =w a ×T onmin , the actual opening duration T of the burner S in the area of the fume outlet of the heating furnace among the burner group S = {S 1 , S 2 , …, S N} during the combustion cycle period T is controlled to be T b = w b ×T b = w b ×T on = w b ×T onmin , the actual opening duration T of other burners S in the burner group S = {S 1 , S 2 , …, S N} during the combustion cycle period T is controlled to be T j = w j ×T j = T j ×T on = T on = T onmin ; S23. If Y p > Y r , weight control is not enabled, and the weight value w 1 of each burner S 2 in the burner group S = {S N} is 1, and the actual on-time T i of each burner S i in the burner group S = {S 1 , S 2 , …, S N} during the combustion cycle period T is controlled as follows: Compare the power output ratio Y i with the burner cycle period conversion threshold Y i . The burner cycle period conversion threshold If Y p > Y s , the combustion cycle period T is converted to the burner reference off-time T p and the burner reference on-time T s which are respectively set as: T off = T on , T off = T - T offmin , and the actual on-time T on of each burner S off in the burner group S = {S 1 , S 2 , …, S N} during the combustion cycle period T is i all i . If Y p < Y s , the combustion cycle period T is converted to the burner reference on-time T on and the burner reference off-time T off which are respectively set as: T on = T onmin , T off = T - T on , and the actual on-time T 1 , S 2 , …, S N} of each burner S i during the combustion cycle period T is i all T i = w i × T on = T on = T onmin .

2. The burner pulse combustion control method based on weighted round-robin scheduling according to claim 1, Characterized in that, The burner group S = {S 1 , S 2 , …, S N} has a burner quantity N = 10. The minimum opening duration T onmin = 10 s, the maximum opening duration T onmax = 297 s, and the minimum closing duration T offmin = 3 s for each burner within a combustion cycle period T.

3. The burner pulse combustion control method based on weighted round-robin scheduling according to claim 1 or 2, Characterized in that, It further includes controlling the opening pulse timing of each burner in the burner group through round-robin scheduling, specifically including: Set the minimum opening waiting time \(T\) 1 for each burner \(S\) 2 in the burner group \(S = \{S\) N , \(S\) i , \(\cdots\), \(S\) d \}; Set the number of ignited burners in the burner group S = {S 1 , S 2 , …, S N} to be K, and the (K + 1)-th burner S k+1 has waited for a time T w , where K = 1, 2, …, N - 1; When T w > T d and at this time, the (K + 1)-th burner S k+1 starts ignition.

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