Steel continuous casting-rolling production scheduling method and system

Abstract

The invention discloses a steel continuous casting-rolling production scheduling method and system, and belongs to the technical field of production scheduling, and the method comprises the steps: obtaining order information, and carrying out the order batch collection according to the steel type, section and delivery date in an order; a flexible block planning method is adopted for planning, and the continuous casting-rolling production stage is divided into a plurality of time slots according to the order production sequence; constructing a continuous casting-rolling production scheduling model based on a time slot distribution strategy; and solving the continuous casting-rolling production scheduling model by adopting a differential evolution algorithm to obtain a continuous casting-rolling optimal production plan, and further discloses a scheduling system. By adopting the production scheduling method and system, the target of shortest time from production completion to rolling of the continuous casting billet is achieved, and the heat loss of the continuous casting billet and the heating consumption of the heating furnace are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of production scheduling, and in particular to a steel continuous casting-rolling production scheduling method and system. Background Art

[0002] The production system of steel enterprises is a complex quasi-continuous / intermittent production process involving numerous processes, equipment, and process technologies. In the process of logistics delivery, not only reliable control of various automated equipment is required, but also close connection and optimization of upstream and downstream processes are required to ensure product quality and complete the task with higher efficiency and lower cost. The steelmaking continuous casting-rolling production process is characterized by high temperature, high pressure, and high speed. At present, the planning method of the rolling process is mostly to consider the preparation of rolling batches and rolling plans after the continuous casting billets arrive at the warehouse, which leads to a long warehouse time for the continuous casting billets and high heat loss. However, the various production processes of the long product production line are closely connected, and most of the continuous casting billets are hot loaded and hot delivered. Therefore, how to integrate the steelmaking continuous casting and rolling units to minimize the time from the completion of production to the rolling of the continuous casting billets, thereby reducing the heat loss of the continuous casting billets and reducing the heating consumption of the heating furnace is an urgent problem to be solved. Summary of the invention

[0003] The purpose of the present invention is to provide a steel continuous casting-rolling production scheduling method and system, by constructing a continuous casting-rolling production scheduling model, to obtain an optimal production plan.

[0004] To achieve the above object, the present invention provides a steel continuous casting-rolling production scheduling method and system, the steps comprising:

[0005] S1. Obtain order information and batch the orders according to the steel type, section and delivery date in the order;

[0006] S2, using a flexible block planning method to plan the steel continuous casting-rolling production stage, dividing the continuous casting-rolling production stage into several time slots according to the order production sequence;

[0007] S3. Construct a continuous casting-rolling production scheduling model based on the time slot allocation strategy;

[0008] S4. Use differential evolution algorithm to solve the continuous casting-rolling production scheduling model and obtain the optimal production plan of continuous casting-rolling.

[0009] Preferably, the flexible block planning method in step S2 includes:

[0010] During the continuous casting stage, the continuous casting machine is divided into several time slots. Orders with the same steel grade and section are produced according to the data in each time slot. The weight of the production batch in each time slot is different.

[0011] During the rolling stage, the rolling mill is divided into several time slots, and orders with the same aperture in each time slot are produced sequentially.

[0012] Preferably, the time slot allocation strategy in step S3 satisfies:

[0013] The production time is divided into several time periods, and there is a time slot on the continuous casting machine and the rolling mill in each production cycle;

[0014] Different continuous casting time slots completed in the same production cycle are merged into a planning block and allocated to the rolling time slot of the next production cycle for rolling.

[0015] Preferably, constructing the continuous casting-rolling production scheduling model in step S3 includes constructing a continuous casting scheduling planning model with the goal of minimizing the total completion time of the casting machine and a rolling scheduling planning model with the goal of minimizing the waiting time of the batch between two stages.

[0016] Preferably, the building of the continuous casting scheduling planning model includes:

[0017] Construct the objective function:

[0018] min f 1

[0019] Construct a completion time constraint that the total completion time is greater than or equal to the last time slot T on any casting machine:

[0020]

[0021] Construct a constraint where the weight of an order with steel type g and section weight satisfying variables X, w is assigned to time slot t of casting machine m for production, and the weight of order t assigned to time slot t of casting machine i is less than the standard weight constraint of order i:

[0022]

[0023] Construct any order i, the standard weight of order i is equal to the sum of its assigned time slots:

[0024]

[0025] Build production batches to meet the minimum production volume requirement constraints:

[0026]

[0027] Construct a formula to calculate the production time of any time slot on any casting machine:

[0028]

[0029] Construct the production constraint of the previous time slot, start production at the next time slot, and the start production time of the time slot is greater than the earliest production time constraint of the time slot:

[0030]

[0031] The construction time slot end production time, and the time slot end production time is not greater than the time slot latest completion time constraint:

[0032]

[0033] In the formula, f 1 represents the total completion time, f 1 ≥0, I represents the order set, M represents the continuous casting machine set, G represents the steel type set, W represents the section set, T represents the time slot set, I g represents the order set of steel type g, I w represents the order set with section w, I m represents the set of orders that can be produced on casting machine m, T i represents the set of time slots that satisfy order production, g i represents the steel type of order i, w i represents the cross section of order i, stw i represents the standard weight of order i, represents the production speed of casting machine m, Indicates the switching time for different steel types and sections. It indicates the minimum weight of casting machine m to start production. represents the earliest production time of time slot t on casting machine m, represents the latest end time of time slot t on casting machine m, Indicates that the steel type g and section w are 1 when they are produced in time slot t on casting machine m, otherwise they are 0. represents the weight of order i assigned to the production of time slot t on casting machine m, represents the production time of time slot t on casting machine m, represents the start time of production in time slot t on casting machine m, Indicates the end time of production in time slot t on casting machine m.

[0034] Preferably, the construction of the rolling scheduling planning model includes:

[0035] Construct the objective function:

[0036] min f 2

[0037] Construct a two-stage waiting time that is greater than or equal to the rolling start time of any batch minus the material arrival time constraint:

[0038]

[0039] Construct the minimum production limit and batch allocation constraints for rolling production:

[0040]

[0041] Construct batch n to be produced in time slot t of rolling line l, and the space corresponding to the batch to be produced in time slot t:

[0042]

[0043] Construct a formula to calculate the actual production time of the rolling mill in any time period:

[0044]

[0045] Construct the production constraint for the previous time slot and the production constraint for the next time slot:

[0046]

[0047] Construct the production of batch n in time slot t of rolling line l, whose actual production start time is equal to the actual production start time of the time slot, and whose actual production completion time is equal to the actual production completion time of the time slot:

[0048]

[0049] In the formula, f 2 represents the maximum waiting time of a batch from continuous casting to rolling, f 2 ≥0, L represents the hot rolling production line set, represents the aperture set, N represents the batch set, and N t represents the batch set produced at time slot t, T represents the time slot set, T n represents the set of time slots for the production of batch n, represents the production speed of rolling line l, Indicates the switching time when the aperture is different, Indicates the rolling line l in the hole diameter Minimum production weight, represents the earliest production time of time slot t of rolling line l, Indicates the latest end time of time slot t of rolling line l, It indicates the minimum weight of casting machine m to start production. represents the earliest production time of time slot t on casting machine m, represents the latest end time of time slot t on casting machine m, represents the actual number of batches n arriving at rolling line l, Indicates aperture The value is 1 when the rolling line l time slot t is in production, otherwise it is 0. Indicates that batch n is assigned to rolling line l with hole diameter The weight of production, Indicates that batch n is assigned to rolling line l with hole diameter 1 when producing, otherwise 0. It means that when batch n is assigned to time slot t of rolling line l, it is 1, otherwise it is 0. represents the production time of time slot t of rolling line l, represents the start time of production in time slot t of rolling line l, represents the start time of production of batch n in time slot t of rolling line l, Indicates the end time of production in time slot t of rolling line l.

[0050] Preferably, in step S4, using the differential evolution algorithm to solve the continuous casting-rolling production scheduling model includes:

[0051] S41, encoding individual elements of the continuous casting-rolling stage, the encoding includes five dimensions: the number of orders to be produced, the production casting machine corresponding to the order, the production sequence on the casting machine, the production rolling line corresponding to the order, and the production sequence on the rolling line;

[0052] S42, hierarchically initialize the population, set the individual dimension and the maximum number of iterations;

[0053] S43, hierarchical setting of mutation mode, the mutation mode of the first dimension, second dimension and fourth dimension elements is:

[0054] V i,G+1 =X i,G +F(X r1,G -X r2,G )

[0055] In the formula, X i,G represents the i-th individual in the G population, X r1,G -X r2,G represents the difference vector, and F represents the coefficient of variation;

[0056] The third and fifth dimensional elements mutate in the following ways:

[0057] V i,G+1 =(1-ω)X i,G +ω[F(X best,G -X i,G )+F(X r1,G -X r2,G )]

[0058] In the formula, ω represents the relaxation factor, X best,G represents the best individual in population G;

[0059] S44, set the crossover strategy, cross the third dimension and the fifth dimension elements, the formula is:

[0060]

[0061] In the formula, represents the j-th dimension element of the i-th individual generated by the crossover, represents the j-th dimension element of the i-th variant individual, rand(0,1) represents a random number between 0 and 1, represents the j-th dimension element of the i-th initial parent individual, and CR represents the crossover probability.

[0062] S45, setting the fitness function, taking the total completion time of the casting machine and the waiting time of the batch in the two stages as the result evaluation criteria, the formula is:

[0063]

[0064] F 1 =f 1 (U i,(G+1) )*α+f 2 (U i,(G+1) )*β

[0065] F 2 =f 1 (X i,G )*α+f 2 (X i,G )*β

[0066] Where U i,(G+1) represents the crossover individual, X i,G represents the initial parent individual, F represents the fitness function, f 1 represents the total completion time of goal 1, f 1 represents the maximum waiting time between the two stages of target 2, and α represents f 1 Weight, β represents f 2 Weight.

[0067] A steel continuous casting-rolling production scheduling system, comprising:

[0068] Information acquisition module: used to obtain basic information of production equipment and order basic information in the steelmaking continuous casting-hot rolling stage of the factory. The basic information of production equipment includes the total number of equipment of each type, the processing time of each equipment and the transportation time between equipment, the specifications of each equipment and the production line model; the basic information of order includes steel type information, delivery date and section information;

[0069] Order batching module: batch orders according to the steel type information, delivery date and section information in the order;

[0070] Condition constraint module: The flexible block planning method is used to divide the continuous casting-rolling production stage into several time slots according to the order production sequence, and constraints are set on the objective function based on the time slot allocation strategy to build a continuous casting-rolling production scheduling model;

[0071] Production scheduling module: solves the constructed production scheduling model based on the post-batch production information of the order set and the basic information of the production equipment to generate production plan information.

[0072] Therefore, the present invention adopts the above-mentioned steel continuous casting-rolling production scheduling method and system, which has the following beneficial effects: by constructing a continuous casting scheduling planning model with the goal of minimizing the total completion time of the casting machine and a rolling scheduling planning model with the goal of minimizing the waiting time of the batch between the two stages, the goal of shortest time from production completion to rolling of the continuous casting billet is achieved, thereby reducing the heat loss of the continuous casting billet and the heating consumption of the heating furnace.

[0073] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] Figure 1 A method flow chart of an embodiment of a steel continuous casting-rolling production scheduling method of the present invention;

[0075] Figure 2 A coding schematic diagram of an embodiment of a steel continuous casting-rolling production scheduling method of the present invention;

[0076] Figure 3 It is a structural diagram of an embodiment of a steel continuous casting-rolling production scheduling system of the present invention. DETAILED DESCRIPTION

[0077] Example

[0078] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings 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.

[0079] Reference Figure 1 The present invention provides a steel continuous casting-rolling production scheduling method, the steps comprising:

[0080] S1. Obtain order information and batch the orders according to the steel type, section and delivery date in the order.

[0081] S2. A flexible block planning method is used to plan the steel continuous casting-rolling production stage, and the continuous casting-rolling production stage is divided into several time slots according to the order production sequence.

[0082] Specifically: During the continuous casting stage, several time slots are divided on the continuous casting machine. Orders with the same steel grade and section in each time slot are produced according to the data. The weight of the production batch in each time slot is different, and the switching time is set for different steel grades and sections.

[0083] During the rolling stage, several time slots are divided on the rolling mill. Orders with the same aperture in each time slot are produced in sequence, and switching time is set when the apertures are different.

[0084] S3. Based on the time slot allocation strategy, a continuous casting-rolling production scheduling model is constructed. The continuous casting-rolling production scheduling model includes a continuous casting scheduling planning model with the goal of minimizing the total completion time of the casting machine and a rolling scheduling planning model with the goal of minimizing the waiting time of the batch between the two stages.

[0085] The time slot allocation strategy satisfies:

[0086] The production time is divided into several time periods, and each production period has a time slot on the continuous casting machine and the rolling mill. The start time of each time slot is not limited to the boundary of a certain time period, but is roughly defined by a time window, which represents the earliest start time and the latest end time of the time slot.

[0087] Different continuous casting time slots completed in the same production cycle are merged into a planning block and allocated to the rolling time slot of the next production cycle for rolling. Due to the flexibility of time slot planning, each time slot can start production in the previous production cycle, but production must be completed before the end of the specified time cycle.

[0088] Building a continuous casting scheduling planning model includes:

[0089] Construct the objective function:

[0090] min f 1

[0091] Construct a completion time constraint that the total completion time is greater than or equal to the last time slot T on any casting machine:

[0092]

[0093] Construct a constraint where the weight of an order with steel type g and section weight satisfying variables X, w is assigned to time slot t of casting machine m, and the weight of order i assigned to time slot t of casting machine m is less than the standard weight constraint of order i:

[0094]

[0095] Construct any order i, the standard weight of order i is equal to the sum of its assigned time slots:

[0096]

[0097] Build production batches to meet the minimum production volume requirement constraints:

[0098]

[0099] Construct a formula to calculate the production time of any time slot on any casting machine:

[0100]

[0101] Construct the production constraint of the previous time slot, start production at the next time slot, and the start production time of the time slot is greater than the earliest production time constraint of the time slot:

[0102]

[0103] The construction time slot end production time, and the time slot end production time is not greater than the time slot latest completion time constraint:

[0104]

[0105] In the formula, f 1 represents the total completion time, f 1 ≥0, I represents the order set, M represents the continuous casting machine set, G represents the steel type set, W represents the section set, T represents the time slot set, I g represents the order set of steel type g, I w represents the order set with section w, I m represents the set of orders that can be produced on casting machine m, T i represents the set of time slots that satisfy order production, g i represents the steel type of order i, w i represents the cross section of order i, stw i represents the standard weight of order i, represents the production speed of casting machine m, Indicates the switching time for different steel types and sections. It indicates the minimum weight of casting machine m to start production. represents the earliest production time of time slot t on casting machine m, represents the latest end time of time slot t on casting machine m, Indicates that the steel type g and section w are 1 when they are produced in time slot t on casting machine m, otherwise they are 0. represents the weight of order i assigned to the production of time slot t on casting machine m, represents the production time of time slot t on casting machine m, represents the start time of production in time slot t on casting machine m, Indicates the end time of production in time slot t on casting machine m.

[0106] It should be noted that each casting machine has different production capacity and production speed, and each casting machine produces different steel grades and sections.

[0107] The construction of rolling scheduling planning model includes:

[0108] Construct the objective function:

[0109] min f 2

[0110] Construct a two-stage waiting time that is greater than or equal to the rolling start time of any batch minus the material arrival time constraint:

[0111]

[0112] Construct the minimum production limit and batch allocation constraints for rolling production:

[0113]

[0114] Construct batch n to be produced in time slot t of rolling line l, and the space corresponding to the batch to be produced in time slot t:

[0115]

[0116] Construct a formula to calculate the actual production time of the rolling mill in any time period:

[0117]

[0118] Construct the production constraint for the previous time slot and the production constraint for the next time slot:

[0119]

[0120] Construct the production of batch n in time slot t of rolling line l, whose actual production start time is equal to the actual production start time of the time slot, and whose actual production completion time is equal to the actual production completion time of the time slot:

[0121]

[0122] In the formula, f 2 represents the maximum waiting time of a batch from continuous casting to rolling, f 2 ≥0, L represents the hot rolling production line set, represents the aperture set, N represents the batch set, and N t represents the batch set produced at time slot t, T represents the time slot set, T n represents the set of time slots for the production of batch n, represents the production speed of rolling line l, Indicates the switching time when the aperture is different, Indicates the rolling line l in the hole diameter Minimum production weight, represents the earliest production time of time slot t of rolling line l, Indicates the latest end time of time slot t of rolling line l, It indicates the minimum weight of casting machine m to start production. represents the earliest production time of time slot t on casting machine m, represents the latest end time of time slot t on casting machine m, represents the actual number of batches n arriving at rolling line l, Indicates aperture The value is 1 when the rolling line l time slot t is in production, otherwise it is 0. Indicates that batch n is assigned to rolling line l with hole diameter The weight of production, Indicates that batch n is assigned to rolling line l with hole diameter 1 when producing, otherwise 0. It means that when batch n is assigned to time slot t of rolling line l, it is 1, otherwise it is 0. represents the production time of time slot t of rolling line l, represents the start time of production in time slot t of rolling line l, represents the start time of production of batch n in time slot t of rolling line l, Indicates the end time of production in time slot t of rolling line l.

[0123] S4. Using differential evolution algorithm to solve the continuous casting-rolling production scheduling model to obtain the optimal production plan of continuous casting-rolling, the steps include:

[0124] S41. Encode individual elements in the continuous casting-rolling stage. The encoding includes five dimensions: the number of orders to be produced, the production casting machine corresponding to the order, the production sequence on the casting machine, the production rolling line corresponding to the order, and the production sequence on the rolling line. The first layer of encoding is the number of the order to be produced. Assuming that there are M orders to be produced during the planning period, the first layer of encoding is initialized to 1, 2,..., M; the second layer of elements is the casting machine number corresponding to the first layer of orders, and the same casting machine number is adjacent to the code; the third layer of encoding is the production sequence of the order on the corresponding casting machine, which is divided into two groups and randomly sorted according to the casting machine number without duplication; the fourth layer of elements is the rolling line number corresponding to the first layer of orders, and the same rolling line number is adjacent to the code; the fifth layer of encoding is the production sequence of the order on the corresponding rolling line, which is randomly sorted according to the rolling line number without duplication. Taking the order quantity of 12, the casting machine numbers initially 7 and 8, and the rolling line numbers initialized to 1-4 as an example, the encoding result is as follows Figure 2 shown.

[0125] S42. Initialize the population in layers, set the individual dimension and the maximum number of iterations.

[0126] S43, setting the variation mode in layers. Since the first dimension order quantity, the second dimension casting machine number and the fourth dimension rolling code are all a mark, they will not change during the variation process regardless of addition or subtraction. Therefore, their variation mode is different from the third and fifth dimension variation modes. Therefore, two variation modes are set.

[0127] The variation modes of the first, second and fourth dimension elements are as follows:

[0128] V i,G+1 =X i,G +F(X r1,G -X r2,G )

[0129] In the formula, X i,G represents the i-th individual in the G population, X r1,G -X r2,G represents the difference vector, and F represents the coefficient of variation.

[0130] The third and fifth dimensional elements mutate in the following ways:

[0131] V i,G+1 =(1-ω)X i,G +ω[F(X best,G -X i,G )+F(X r1,G -X r2,G )]

[0132] In the formula, ω represents the relaxation factor, X best,G Represents the best individual in population G.

[0133] S44, set the crossover strategy. Since the first dimension order quantity, the second dimension casting machine number and the fourth dimension rolling code are meaningless, only the third and fifth dimension elements are crossed. The formula is:

[0134]

[0135] In the formula, represents the j-th dimension element of the i-th individual generated by the crossover, represents the j-th dimension element of the i-th variant individual, rand(0,1) represents a random number between 0 and 1, represents the j-th dimension element of the i-th initial parent individual, and CR represents the crossover probability.

[0136] The crossover process includes:

[0137] Determine the crossover individual and the crossover position. Select the initial target individual and the variant individual for crossover operation, and randomly select an integer from 0 to M as the crossover point.

[0138] Determine the crossover method, randomly generate a random number between 0 and 1, and compare it with the crossover coefficient. When rand(0,1)≤CR, crossover is performed, otherwise the initial individual is retained.

[0139] Correct the generated individual fonts. After the crossover operation, the individuals obtained may be repeated, and some elements may not appear. In order to ensure uniqueness, it is necessary to remove the repeated individuals and fill them with numbers that have not appeared.

[0140] Finally, verify the offspring individuals.

[0141] S45, setting the fitness function, taking the total completion time of the casting machine and the waiting time of the batch in the two stages as the result evaluation criteria, the formula is:

[0142]

[0143] F 1 =f 1 (U i,(G+1) )*α+f 2 (U i,(G+1) )*β

[0144] F 2 =f 1 (X i,G )*α+f 2 (X i,G )*β

[0145] Where U i,(G+1) represents the crossover individual, X i,G represents the initial parent individual, F represents the fitness function, f 1 represents the total completion time of goal 1, f 1 represents the maximum waiting time between the two stages of target 2, and α represents f 1 Weight, β represents f 2 Weight.

[0146] The individuals after crossover are decoded and the fitness function is used to select individuals with better fitness values ​​to enter the next generation, and the optimal fitness value is recorded. At the same time, the optimal value of each generation of individuals is selected through each iteration until the optimal value of the optimization problem is found.

[0147] A steel continuous casting-rolling production scheduling system, comprising:

[0148] Information acquisition module: used to obtain basic information of production equipment and order basic information in the steelmaking continuous casting-hot rolling stage of the factory. The basic information of production equipment includes the total number of equipment of each type, the processing time of each equipment and the transportation time between equipment, the specifications of each equipment and the production line model; the basic information of order includes steel type information, delivery date and section information;

[0149] Order batching module: batch orders according to the steel type information, delivery date and section information in the order;

[0150] Condition constraint module: The flexible block planning method is used to divide the continuous casting-rolling production stage into several time slots according to the order production sequence, and constraints are set on the objective function based on the time slot allocation strategy to build a continuous casting-rolling production scheduling model;

[0151] Production scheduling module: solves the constructed production scheduling model based on the post-batch production information of the order set and the basic information of the production equipment to generate production plan information.

[0152] Therefore, the present invention adopts the above-mentioned steel continuous casting-rolling production scheduling method and system, by constructing a continuous casting scheduling planning model with the goal of minimizing the total completion time of the casting machine and a rolling scheduling planning model with the goal of minimizing the waiting time of the batch between the two stages, and using the differential evolution algorithm for solving, the optimal production plan is obtained, and the goal of shortest time from production completion to rolling of the continuous casting billet is achieved, thereby reducing the heat loss of the continuous casting billet and the heating consumption of the heating furnace.

[0153] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A steel continuous casting-rolling production scheduling method, characterized in that the steps include: S1. Obtain order information and batch the order according to the steel type, section and delivery date in the order; S2, using a flexible block planning method to plan the steel continuous casting-rolling production stage, dividing the continuous casting-rolling production stage into several time slots according to the order production sequence; S3. Construct a continuous casting-rolling production scheduling model based on the time slot allocation strategy; S4. Use differential evolution algorithm to solve the continuous casting-rolling production scheduling model and obtain the optimal production plan of continuous casting-rolling.

2. A steel continuous casting-rolling production scheduling method according to claim 1, characterized in that: The flexible block planning method in step S2 includes: During the continuous casting stage, the continuous casting machine is divided into several time slots. Orders with the same steel grade and section are produced according to the data in each time slot. The weight of the production batch in each time slot is different. During the rolling stage, the rolling mill is divided into several time slots, and orders with the same aperture in each time slot are produced sequentially.

3. A steel continuous casting-rolling production scheduling method according to claim 2, characterized in that: The time slot allocation strategy in step S3 satisfies: The production time is divided into several time periods, and there is a time slot on the continuous casting machine and the rolling mill in each production cycle; Different continuous casting time slots completed in the same production cycle are merged into a planning block and allocated to the rolling time slot of the next production cycle for rolling.

4. A steel continuous casting-rolling production scheduling method according to claim 3, characterized in that: The construction of the continuous casting-rolling production scheduling model in step S3 includes constructing a continuous casting scheduling planning model with the goal of minimizing the total completion time of the casting machine and a rolling scheduling planning model with the goal of minimizing the waiting time of the batch between the two stages.

5. A steel continuous casting-rolling production scheduling method according to claim 4, characterized in that: The construction of the continuous casting scheduling planning model includes: Construct the objective function: min f1 Construct a completion time constraint that the total completion time is greater than or equal to the last time slot T on any casting machine: Construct a constraint where the weight of an order with steel type g and section weight satisfying variables X, w is assigned to time slot t of casting machine m, and the weight of order i assigned to time slot t of casting machine m is less than the standard weight constraint of order i: Construct any order i, the standard weight of order i is equal to the sum of its assigned time slots: Build production batches to meet the minimum production volume requirement constraints: Construct a formula to calculate the production time of any time slot on any casting machine: Construct the production constraint of the previous time slot, start production at the next time slot, and the start production time of the time slot is greater than the earliest production time constraint of the time slot: The construction time slot end production time, and the time slot end production time is not greater than the time slot latest completion time constraint: Where f1 represents the total completion time, f1 ≥ 0, I represents the order set, M represents the continuous casting machine set, G represents the steel type set, W represents the section set, T represents the time slot set, and I g represents the order set of steel type g, I w represents the order set with section w, I m represents the set of orders that can be produced on casting machine m, T i represents the set of time slots that satisfy order production, g i represents the steel type of order i, w i represents the cross section of order i, stw i represents the standard weight of order i, represents the production speed of casting machine m, Indicates the switching time for different steel types and sections. It indicates the minimum weight of casting machine m to start production. represents the earliest production time of time slot t on casting machine m, represents the latest end time of time slot t on casting machine m, Indicates that the steel type g and section w are 1 when they are produced in time slot t on casting machine m, otherwise they are 0. represents the weight of order i assigned to the production of time slot t on casting machine m, represents the production time of time slot t on casting machine m, represents the start time of production in time slot t on casting machine m, Indicates the end time of production in time slot t on casting machine m.

6. A steel continuous casting-rolling production scheduling method according to claim 5, characterized in that: The construction of the rolling scheduling planning model includes: Construct the objective function: min f2 Construct a two-stage waiting time that is greater than or equal to the rolling start time of any batch minus the material arrival time constraint: Construct the minimum production limit and batch allocation constraints for rolling production: Construct batch n to be produced in time slot t of rolling line l, and the space corresponding to the batch to be produced in time slot t: Construct a formula to calculate the actual production time of the rolling mill in any time period: Construct the production constraint for the previous time slot and the production constraint for the next time slot: Construct the production of batch n in time slot t of rolling line l, whose actual production start time is equal to the actual production start time of the time slot, and whose actual production completion time is equal to the actual production completion time of the time slot: Where f2 represents the maximum waiting time from continuous casting to rolling of a batch, f2 ≥ 0, L represents the hot rolling production line set, represents the aperture set, N represents the batch set, and N t represents the batch set produced at time slot t, T represents the time slot set, T n represents the set of time slots for the production of batch n, represents the production speed of rolling line l, Indicates the switching time when the aperture is different, Indicates the rolling line l in the hole diameter Minimum production weight, represents the earliest production time of time slot t of rolling line l, Indicates the latest end time of time slot t of rolling line l, It indicates the minimum weight of casting machine m to start production. represents the earliest production time of time slot t on casting machine m, represents the latest end time of time slot t on casting machine m, represents the actual number of batches n arriving at rolling line l, Indicates aperture The value is 1 when the rolling line l time slot t is in production, otherwise it is 0. Indicates that batch n is assigned to rolling line l with hole diameter The weight of production, Indicates that batch n is assigned to rolling line l with hole diameter 1 when producing, otherwise 0. It means that the batch n is assigned to the rolling line l time slot t for production, which is 1, otherwise it is 0. represents the production time of time slot t of rolling line l, represents the start time of production in time slot t of rolling line l, represents the start time of production of batch n in time slot t of rolling line l, Indicates the end time of production in time slot t of rolling line l.

7. A steel continuous casting-rolling production scheduling method according to claim 6, characterized in that: In step S4, the differential evolution algorithm is used to solve the continuous casting-rolling production scheduling model, including: S41, encoding individual elements of the continuous casting-rolling stage, the encoding includes five dimensions: the number of orders to be produced, the production casting machine corresponding to the order, the production sequence on the casting machine, the production rolling line corresponding to the order, and the production sequence on the rolling line; S42, hierarchically initialize the population, set the individual dimension and the maximum number of iterations; S43, hierarchical setting of mutation mode, the mutation mode of the first dimension, second dimension and fourth dimension elements is: V i,G+1 =X i,G +F(X r1,G -X r2,G ) Where, X i,G represents the i-th individual in the G population, X r1,G -X r2,G represents the difference vector, and F represents the coefficient of variation; The third and fifth dimensional elements mutate in the following ways: V i,G+1 =(1-ω)X i,G +ω[F(X best,G -X i,G )+F(X r1,G -X r2,G )] In the formula, ω represents the relaxation factor, X best,G represents the best individual in population G; S44, set the crossover strategy, cross the third dimension and the fifth dimension elements, the formula is: In the formula, represents the j-th dimension element of the i-th individual generated by the crossover, represents the j-th dimension element of the i-th variant individual, rand(0,1) represents a random number between 0 and 1, represents the j-th dimension element of the i-th initial parent individual, and CR represents the crossover probability. S45, setting the fitness function, taking the total completion time of the casting machine and the waiting time of the batch in the two stages as the result evaluation criteria, the formula is: F1=f1(U i,(G+1) )*α+f2(U i,(G+1) )*β F2=f1(X i,G )*α+f2(X i,G )*β Where U i,(G+1) represents the crossover individual, X i,G represents the initial parent individual, F represents the fitness function, f1 represents the total completion time of goal 1, f2 represents the maximum waiting time between the two stages of goal 2, α represents the weight of f1, and β represents the weight of f2.

8. A steel continuous casting-rolling production scheduling system, characterized in that: include: Information acquisition module: used to obtain basic information of production equipment and order basic information in the steelmaking continuous casting-hot rolling stage of the factory. The basic information of production equipment includes the total number of equipment of each type, the processing time of each equipment and the transportation time between equipment, the specifications of each equipment and the production line model; the basic information of order includes steel type information, delivery date and section information; Order batching module: batch orders according to the steel type information, delivery date and section information in the order; Condition constraint module: The flexible block planning method is used to divide the continuous casting-rolling production stage into several time slots according to the order production sequence, and constraints are set on the objective function based on the time slot allocation strategy to build a continuous casting-rolling production scheduling model; Production scheduling module: solves the constructed production scheduling model based on the post-batch production information of the order set and the basic information of the production equipment to generate production plan information.

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