Industrial load scheduling method for new energy consumption

Abstract

The invention provides an industrial load scheduling method for new energy consumption, and relates to the technical field of new energy and energy conservation. According to the method, the magnesite production process is considered in the scheduling plan, and particularly, the constraint of the electrical smelting furnace production engineering on the load regulation is involved, so that the new energy consumption capacity in an enterprise can be improved while the product quality and efficiency are ensured, and the economic benefit of the enterprise is improved by saving the energy consumption overhead of the enterprise. The configuration and regulation of the electric energy storage device and the heat energy storage device are considered at the same time, the capacity of meeting the electric load and the heat load of the electric smelting magnesium furnace is achieved while the short-time consumption capacity of new energy is improved, and the capacity of interference resistance and reliable and stable operation of the system is further improved. A multi-objective optimization scheduling model is established, and a two-stage relaxation algorithm is used for solving, so that the dimension of the model is reduced, and the calculation efficiency during solving is improved.

Description

Technical Field

[0001] The present invention belongs to the field of new energy and energy-saving technology, and in particular relates to an industrial load dispatching method for new energy consumption. Background Art

[0002] In recent years, the total installed capacity of new energy, mainly wind power and photovoltaics, has continued to increase in my country's total new installed capacity. The uncertainty of new energy output and the uncertainty of emerging load response have increased the volatility of the power grid's supply and demand balance. The balance characteristics and methods of the power system are undergoing profound changes. The difficulty of maintaining system balance is also increasing, and the problem of lack of flexible adjustment resources is becoming increasingly prominent.

[0003] Industrial loads usually account for a large proportion in the power system. my country's industrial loads are large in scale, regular, and controllable, with huge potential for regulation. They are the priority for resource mining and development on the demand side. Typical types include steel, magnesia, and electrolytic aluminum. Industrial loads have large single-unit capacity and strong controllability, and have huge potential for power regulation. At the same time, industrial enterprises have a strong desire to break through the dual pressures of economy and environment through new energy power supply.

[0004] In the study of coordinated operation strategies for different regulatory entities in different scenarios, Xubin Liu et al. proposed a PBC strategy based on the Euler-Lagrange (EL) model for industrial distribution networks under asymmetric voltage sag conditions. According to the passive control theory, a passive-based controller was designed using a new positive and negative sequence damping injection method. The power distribution of parallel multi-inverters was studied to achieve coordinated operation. Gong, Feixiang et al. proposed a grid emergency frequency control method based on the coordination of submerged arc furnace load and energy storage. The system frequency deviation is introduced into the submerged arc furnace and energy storage loads so that their active power can respond quickly to frequency changes, provide rapid power support for the power grid, and ensure system frequency stability. In order to achieve the dual optimization goals of economic and environmental operation of microgrid systems, Hong Bowen and others from Tianjin University established a general model of multi-objective dynamic optimization scheduling of microgrids with independent system simulation modules and operation optimization modules as the core; Fu Yimu and others from South China University of Technology established a multi-objective stochastic dynamic economic scheduling model with the goals of minimizing total fuel consumption and electricity purchase costs for power systems with wind power access, and used the scenario method to transform the model into a large-scale multi-objective deterministic dynamic economic scheduling model.

[0005] It can be seen that although large-capacity industrial loads have adjustable capabilities, due to complex process conditions and difficulties in defining the safety interface of equipment adjustment, the adjustment effect is not ideal in the face of multiple scenarios such as the consumption of distributed photovoltaics and grid interactive response, and the regulation potential of industrial loads cannot be fully utilized. The coordinated operation control method of large-capacity industrial loads and new energy is also difficult to apply in practice. How to better stimulate industrial loads to actively participate in system regulation and promote the efficient operation of new power systems has become a focus of attention in all sectors of the industry. Making full use of the adjustable resource potential of industrial loads is crucial to achieving reliable operation and flexible regulation of power systems. A large number of studies have been conducted at home and abroad on the coordinated operation of different control subjects in different scenarios, but most of them are studies on drone formations, multi-agent systems, power system voltage control, etc., and there are few studies on the autonomous and coordinated control of large-capacity industrial loads and new energy. Summary of the invention

[0006] In view of the shortcomings of the existing technology, the present invention provides an industrial load scheduling method for new energy consumption. Based on various types of production processes and safe operating conditions, a large-capacity industrial load coordinated operation strategy is established to maximize the new energy consumption and reduce the abandonment rate of photovoltaic power generation, providing new ideas for subsequent research on new energy optimization operation and large-capacity industrial load operation strategy research.

[0007] In a first aspect, the present invention provides an industrial load dispatching method for new energy consumption, comprising:

[0008] Constructing a cost model of magnesite load and a load model of magnesite load, and constructing operation constraints of the cost model of magnesite load and the load model of magnesite load;

[0009] Construct an operating cost model for the energy storage system and determine the configuration constraints and operating constraints of the operating cost model for the energy storage system;

[0010] Construct the power balance constraints and thermal balance constraints of the industrial park;

[0011] Establish the objective function of minimizing the operating cost and the objective function of maximizing the consumption of new energy respectively;

[0012] The established cost model of magnesite load, the load model of magnesite load, the operating constraints of the cost model of magnesite load and the load model of magnesite load, the operating cost model of energy storage system and its configuration constraints and operating constraints, the power balance constraints and thermal balance constraints of the industrial park and the objective function of minimizing operating costs and maximizing new energy consumption are used as a multi-objective optimization scheduling model;

[0013] Using the photovoltaic control strategy for industrial load absorption, a preliminary load dispatching plan for the industrial park is obtained;

[0014] Based on the multi-objective optimization scheduling model, the robust stochastic optimization algorithm is used to optimize the preliminary industrial park load scheduling plan to obtain the final industrial park load scheduling plan;

[0015] The load model of the magnesite load is:

[0016]

[0017] Where p(k) is the power of the kth fused magnesium furnace, k is the number of the fused magnesium furnace, and I arc-k (t) is the arc melting current of the kth electric magnesium furnace at the tth time node, t is the number of the time node, n t is the number of time nodes, U is the external voltage of the electric fused magnesium furnace, and cosφ is the power factor;

[0018] The arc melting current of the kth electric magnesium melting furnace at the tth time node is:

[0019]

[0020] In the formula, I arc-a (t), I arc-b (t) and I arc-c (t) are the average arc melting currents during the start-up, stabilization and shutdown processes of the magnesite process, t a is the start-up duration of the fused magnesium furnace, t b is the duration of the stable process of the fused magnesium furnace, t c is the duration of the shutdown process of the fused magnesium furnace, which is calculated based on the historical data of the fused magnesium furnace recorded by the enterprise; t k It is the starting time node of the entire electric melting process;

[0021] The cost model of the magnesite load is expressed as:

[0022] C arc =C in K emis +C CH +C heat (3)

[0023] In the formula, C arc is the total operating cost of the fused magnesium furnace, C in Indicates the equivalent electricity price of the electricity input into the fused magnesium furnace; K emis is the heat dissipation coefficient, which characterizes the heat loss to the air during the smelting process; C CH is the power loss, which represents the equivalent power loss caused by the thermal effect of the wire current during the transmission process; C heatRepresents heat loss, which indicates the equivalent power loss caused by the heat dissipated during the natural cooling process after the entire electric melting process is completed;

[0024] The cost model of the magnesite load and the operation constraints of the load model of the magnesite load include arc melting current constraints, electric molten magnesium furnace input power constraints and voltage constraints;

[0025] The arc melting current constraint is:

[0026]

[0027] Among them, I arc-a.n ,I arc-b.n and I arc-c.n They represent the rated values ​​of arc melting current in the start-up, stabilization and shutdown stages, ε1, ε2 and ε3 represent the allowable fluctuation values ​​in the start-up, stabilization and shutdown stages, I arc-a (t), I arc-b (t) and I arc-c (t) are the average arc melting currents in the start-up, stabilization and shutdown stages respectively;

[0028] The input power constraint and voltage constraint of the fused magnesium furnace are:

[0029] P k,min ≤P k (t)≤P k,max (5)

[0030] U k,min ≤U k (t)≤U k,max (6)

[0031] Where P k (t) represents the electric power input to the kth electric magnesium furnace at time t, P k,min and P k,max They represent the minimum and maximum power allowed by the kth electric magnesium furnace; U k (t) represents the voltage of the kth electric magnesium furnace at time t, U k,min and U k,max They respectively represent the minimum voltage and maximum voltage allowed for the kth electric fused magnesium furnace.

[0032] The energy storage system includes an electric energy storage device and a thermal energy storage device, and the operation cost model of the energy storage system includes an operation cost model of the electric energy storage device and an operation cost model of the thermal energy storage device;

[0033] The operating cost model of the electric energy storage device includes two parts: equipment loss cost and energy loss cost;

[0034] The equipment loss cost of the electric energy storage device is:

[0035]

[0036] In the formula, C soc is the equipment loss cost of the electric energy storage device, is the cost price of the capacity availability of the electric energy storage device;

[0037]

[0038] In the formula, C install Represents the installation cost of the electric energy storage device; C ∑ Indicates the total life cycle capacity of the electric energy storage device; C N Indicates the rated capacity of the electric energy storage device; L soc Indicates the rated life of the electric energy storage device; DOD soc Indicates the discharge depth of the electrical energy storage device;

[0039] The energy loss cost of the electric energy storage device includes the energy loss cost under the discharge condition, the charging condition and the energy storage condition;

[0040] The energy loss cost of the electric energy storage device during discharge operation is:

[0041]

[0042] In the formula, is the energy loss cost of the electric energy storage device during discharge operation, Represents the output power of the electric energy storage device, K disp Indicates the power loss cost coefficient when the electric energy storage device outputs power;

[0043] The energy loss cost of the electric energy storage device under charging conditions is:

[0044]

[0045] In the formula, is the energy loss cost of the electric energy storage device under charging conditions, Represents the input power of the electric energy storage device, K char It represents the power loss cost coefficient when the electric energy storage device inputs energy;

[0046] The energy loss cost of the energy storage device in the energy storage condition is:

[0047]

[0048] In the formula, Energy loss cost for energy storage conditions of electric energy storage devices, represents the current storage capacity of the electric energy storage device, γ represents the energy loss coefficient of the electric energy storage device when storing energy, K store It represents the power loss cost coefficient when the electric energy storage device stores energy;

[0049] The thermal energy storage device includes an electric boiler and a heat storage tank. The operation cost model of the thermal energy storage device includes the operation cost model of the heat storage tank and the electric boiler:

[0050] C eb =C eb.tot (1-K tran ) (13)

[0051] C heat =C heat.in.loss +C heat.emis +C heat.out.loss (14)

[0052] In the formula, C eb and C heat are the operating costs of the electric boiler and the heat storage tank respectively; C eb.tot The production cost of the total amount of electric energy input to the electric boiler within a certain period of time. When the electric energy input to the electric boiler comes entirely from new energy, this item is 0; K tran is the electric heat transfer coefficient of the electric boiler; C heat.in.loss and C heat.out.loss are the heat loss costs when the heat storage tank stores and releases heat, C heat.emis The heat dissipation cost of the heat storage tank during a certain period of time;

[0053] The energy storage system includes an electric energy storage device and a thermal energy storage device, and the configuration constraints of the operation cost model of the energy storage system include capacity constraints and power constraints;

[0054] The capacity and power constraints of the electric energy storage device are:

[0055]

[0056] In the formula, is the rated capacity of the electric energy storage device configured for the kth electric fused magnesium furnace, and are the upper and lower limits of the rated capacity of the electric energy storage device configured for the kth electric fused magnesium furnace; x soc The number of fused magnesium furnaces deployed in the park, is the rated power of the electric energy storage device configured for the kth electric magnesium furnace, and are the upper and lower limits of the rated power of the electric energy storage device configured for the kth electric fused magnesium furnace; soc.max and x soc.minThe maximum and minimum number of electric energy storage devices that can be configured in the entire industrial park;

[0057] The operating constraints of the electric energy storage device are:

[0058]

[0059] In the formula, and are the charging state parameter and discharging state parameter of the electric energy storage device configured for the kth electric magnesium furnace at time t, both of which are 0-1 variables, 0 for invalid and 1 for valid. The following example illustrates: when the charging state variable is 1, it indicates that the electric energy storage device is in the charging state in the current time period (or time); when the discharging state variable is 1, it indicates that the electric energy storage device is in the discharging state. It should be noted that for economic considerations, the electric energy storage device cannot be in the charging and discharging states at the same time, so at most only one state variable can be 1. The first expression essentially constrains the electric energy storage device from being charged and discharged at the same time; and are the charging power and discharging power of the electric energy storage device configured for the kth electric magnesium furnace at time t, Indicates the rated maximum capacity of the electric energy storage device, E soc.k.t The energy storage capacity of the electric energy storage device configured for the kth electric fused magnesium furnace at time t;

[0060] Thermal energy storage device capacity constraints and power constraints:

[0061]

[0062] Where P eb.k is the electric power of the thermal energy storage device configured for the kth electric magnesium furnace, and are the upper and lower limits of the rated power of the thermal energy storage device configured for the kth electric fused magnesium furnace; is the thermal power of the heat storage tank in the thermal energy storage device configured for the kth electric magnesium furnace, and are respectively the upper limit and lower limit of the rated thermal power of the heat storage tank in the thermal energy storage device configured for the kth electric fused magnesium furnace; is the current heat storage capacity of the heat storage tank in the thermal energy storage device configured for the kth electric magnesium furnace, and are the upper and lower limits of the rated capacity of the heat storage tank in the thermal energy storage device configured for the kth electric fused magnesium furnace; eb.max is the maximum number of configurable thermal energy storage devices, x eb is the total number of thermal energy storage devices installed;

[0063] The thermal energy storage device includes an electric boiler and a heat storage tank. The operation constraints of the electric boiler are:

[0064]

[0065] In the formula, H eb.k.t is the thermal power generated by the electric boiler in the thermal energy storage device configured for the kth electric fused magnesium furnace at time t, and η is the electric heating conversion rate of the electric boiler;

[0066] The operating constraints of the thermal storage tank are:

[0067]

[0068] In the formula, and are the heat storage state and heat release state of the heat storage tank in the heat storage device configured for the kth electric fused magnesium furnace at time t; and are the heat storage power and heat release power of the heat storage tank in the thermal energy storage device configured for the kth electric fused magnesium furnace at time t; S heat.k.t is the heat storage capacity of the heat storage tank in the heat storage device configured for the kth electric fused magnesium furnace at time t;

[0069] The power balance constraint of the industrial park is:

[0070]

[0071] Where P thermal is the electric energy purchased from the thermal power plant outside the industrial park at time t; PV.t is the photovoltaic power generation power at time t; P arc.k.t is the electric power consumed by the kth electric magnesium furnace at time t;

[0072]

[0073] In the formula, is the predicted value of photovoltaic power generation at time t; as well as is a variable, with a value of 0 or 1; Γ is the photovoltaic uncertainty parameter; is the upward fluctuation of photovoltaic power generation, It is the downward fluctuation amount of photovoltaic power generation;

[0074] The thermodynamic balance constraint is:

[0075]

[0076] In the formula, H arc.k.t is the heat generated by the arc in the kth electric magnesium furnace at time t; H load.k.t is the heat load of the kth electric magnesium furnace at time t;

[0077] The objective function for minimizing the operating cost is:

[0078]

[0079] Where F is the total operating cost of the entire industrial park load, C PV and C arc They represent the operating costs of photovoltaic power generation and electric magnesium furnace at time t, and Respectively represent the operating status of photovoltaic power generation, electric boiler, heat storage tank, electric energy storage device and electric magnesium furnace at time t, and the value is 0 or 1; C control To control costs:

[0080] C control =|C1*ΔP M *Δt| (25)

[0081]

[0082] Where ΔP M is the adjustment power; Δt is the adjustment duration; C1 is the unit control cost coefficient; F P Indicates the unit load price, RMB / MWh; F c is the unit load cost; α is the percentage of electricity consumption cost in the production cost of the industrial park; η arc For the efficiency of electricity production;

[0083] The objective function for maximizing new energy consumption is:

[0084]

[0085] Where P PV.emis is the unused photovoltaic power; P PV is the photovoltaic power generation power, P eb and P soc are the photovoltaic rates used by the electric boiler and the power storage device respectively; P arc.PV is the photovoltaic power used by the electric magnesium furnace, is the working status of the fused magnesium furnace at each time node, and its value is 0 or 1;

[0086] The photovoltaic control strategy for industrial load consumption is specifically as follows:

[0087] S1: Determine the photovoltaic power generation power to be absorbed;

[0088] S2: Determine the absorption capacity of the molten magnesium furnace, the electric energy storage device and the thermal energy storage device. If there is an molten magnesium furnace, the electric energy storage device or the thermal energy storage device that has the ability to absorb photovoltaic power, execute S3; otherwise, terminate the absorption and execute S7;

[0089] S3: Determine the type of equipment that currently has the ability to absorb photovoltaic power;

[0090] S4: Calculate the control cost of the equipment according to the equipment type; the equipment types include electric fused magnesium furnace, electric energy storage device and thermal energy storage device;

[0091] The control cost of the electric magnesium furnace is calculated using the calculation formula of the control cost; for the electric energy storage device, its control cost is its operating cost; for the thermal energy storage device, its control cost is its operating cost;

[0092] S5: Compare the control costs of various types of equipment and select the equipment with the lowest control cost to fully absorb photovoltaic power;

[0093] S6: Determine whether there is still photovoltaic power that needs to be absorbed. If yes, return to step S1; otherwise, terminate the absorption and execute step S7. Meanwhile, if the equipment control cost is greater than the utilization benefit after absorption according to step S5, then terminate the absorption and execute step S7.

[0094] S7: according to the difference between the power required by each device and the photovoltaic power generation power consumed, the power purchased by the thermal power plant of the device is obtained, and then a preliminary load dispatching plan for the industrial park is obtained; the load dispatching plan for the industrial park includes the photovoltaic power generation power allocated to different types of equipment and the power purchased by the thermal power plant;

[0095] In a second aspect, the present invention provides an industrial load dispatching system for new energy consumption, which is used to implement an industrial load dispatching method for new energy consumption, including a model and constraint building module, an industrial park load dispatching solution module and an industrial park load dispatching solution optimization module;

[0096] The model and constraint building module is used to build a multi-objective optimization scheduling model, and the target optimization scheduling model includes a cost model of magnesite load, a load model of magnesite load, an operation constraint of the cost model of magnesite load and the load model of magnesite load, an operation cost model of the energy storage system and its configuration constraint and operation constraint, an electric power balance constraint and a thermal balance constraint of the industrial park, and an objective function of minimizing the operation cost and maximizing the consumption of new energy;

[0097] The industrial park load dispatching solution module is used to obtain a preliminary industrial park load dispatching solution by utilizing the photovoltaic control strategy for industrial load consumption;

[0098] The industrial park load scheduling scheme optimization module is used to optimize the preliminary industrial park load scheduling scheme obtained based on the multi-objective optimization scheduling model using a robust stochastic optimization algorithm to obtain a final industrial park load scheduling scheme;

[0099] In a third aspect, the present invention provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, an industrial load dispatching method for new energy consumption is described;

[0100] In a fourth aspect, the present invention provides a computer-readable storage medium, in which a computer program is stored. When the computer program is executed by a processor, the industrial load scheduling method for new energy consumption is implemented.

[0101] Existing methods for considering industrial load scheduling usually start from the perspective of the power grid, based on the load level and scheduling characteristics of the industrial load itself, but rarely consider the problem of reduced production efficiency caused by industrial load regulation under production process constraints. In response to this problem, the beneficial results of the present invention are:

[0102] 1. Taking the magnesite production process into consideration in the scheduling plan, especially the constraints on load control of the electric fused magnesium furnace production project, can improve the company's internal new energy consumption capacity while ensuring product quality and efficiency, and improve the company's economic benefits by saving the company's energy costs.

[0103] 2. Considering the configuration and regulation of both electric energy storage devices and thermal energy storage devices at the same time, while improving the short-term absorption capacity of new energy, it also has the ability to meet the electrical load and thermal load of the electric magnesium furnace at the same time, further improving the system's anti-interference and reliable and stable operation capabilities.

[0104] 3. Considering the two optimization goals of minimizing system operating costs and maximizing new energy consumption at the same time, comprehensively considering the production process constraints of the electric molten magnesium furnace, the operating constraints of the electric energy storage device and the thermal energy storage device, a multi-objective optimization scheduling model is established, and a two-stage relaxation algorithm is used for solving it, which reduces the model dimension and improves the computational efficiency during solution.

[0105] 4. Provide a scheduling strategy for the internal consumption of new energy in industrial enterprises, improve their photovoltaic consumption capacity, and reduce the internal energy costs of enterprises while ensuring the safe and stable operation of electric magnesium furnaces. BRIEF DESCRIPTION OF THE DRAWINGS

[0106] Figure 1 This is a main wiring diagram of the magnesia industry in an embodiment of the present invention;

[0107] Figure 2This is a process flow chart of the magnesia industry in an embodiment of the present invention;

[0108] Figure 3 This is a flow chart of the photovoltaic consumption strategy in an embodiment of the present invention;

[0109] Figure 4 A curve diagram showing the prediction of sunlight intensity for a certain day in an embodiment of the present invention;

[0110] Figure 5 A photovoltaic power output diagram predicted for a certain day in an embodiment of the present invention;

[0111] Figure 6 Flow chart of a robust stochastic optimization solution algorithm in an embodiment of the present invention;

[0112] Figure 7 A power output distribution diagram for a certain day in an embodiment of the present invention;

[0113] Figure 8 It is a curve diagram of power and storage capacity change of a solar energy storage device in an embodiment of the present invention. DETAILED DESCRIPTION

[0114] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0115] An industrial load dispatching method for new energy consumption includes the following steps:

[0116] like Figure 1 As shown, the present invention is aimed at the new energy consumption scenario of industrial enterprises in the magnesia industry, including a power system and an industrial park. The power system includes a photovoltaic power plant and a power grid (thermal power generation). The industrial park includes four production workshops (with electric magnesium furnaces as the main energy-consuming equipment), a set of electric energy storage devices in the park (for storing the electricity generated by the photovoltaic power plant, and using the stored low-priced new energy electricity to partially replace the high-priced thermal power energy), four sets of thermal energy storage devices in the production workshops (for storing excess thermal energy for use in the electric magnesium furnace) and conventional loads such as lighting, cooling and heating; the new energy form involved is a centralized photovoltaic power plant outside the industrial park, and photovoltaic electricity is taken into consideration in an overall form. The purpose of this method is to achieve the optimal economy of the overall operation of the industrial park on the basis of considering the production process of the industrial park.

[0117] Step 1: Based on the actual production process flow and actual industrial load data of magnesite load, a cost model of magnesite load and a load model of magnesite load are constructed, and the operation constraints of the cost model of magnesite load and the load model of magnesite load are constructed according to the process; the operation constraints include arc melting current constraints, electric magnesium furnace input power constraints and voltage constraints;

[0118] The main production process of the magnesite load model studied in this patent is as follows: Figure 2 As shown, it includes: using magnesite ore as raw material, including flotation, material preparation and pressing, raw material transportation, high-temperature electric melting, cooling, shelling, skin sand stripping, screening, crushing and manual picking, and then obtaining the fused magnesia product. When modeling, the fused magnesium furnace used for high-temperature electric melting is mainly studied. When using magnesite fused magnesia, high temperature is generated by electric arc heating to melt the magnesite ore (MgCO3) into fused magnesium lumps at about 2800℃ in the furnace. According to the smelting time, the whole smelting process can be roughly divided into the furnace start-up, stabilization and furnace shutdown stages.

[0119] Analyzing the characteristics of different smelting stages, the furnace start-up stage is to turn on the power and draw the arc to start the furnace, which takes about 30 minutes. Intense arc discharge is generated between the electrode blocks at the bottom of the furnace and the furnace temperature rises rapidly; the stabilization stage is about 10 hours, and it is necessary to ensure that the electrode electric melting current is within the specified range, which is mainly achieved by adjusting the electrode height; the furnace sealing stage is about 30 minutes before the end, at which time the liquid level is close to the top of the furnace shell. When the molten pool rises to the upper surface of the furnace shell, the power supply is stopped and the melting process ends.

[0120] The load model of the magnesite load is:

[0121]

[0122] Where p(k) is the power of the kth fused magnesium furnace, k is the number of the fused magnesium furnace, and I arc-k (t) is the arc melting current of the kth electric magnesium furnace at the tth time node, t is the number of the time node, n t is the number of time nodes, U is the external voltage of the electric fused magnesium furnace, and cosφ is the power factor;

[0123] The arc melting current of the kth electric magnesium melting furnace at the tth time node is:

[0124]

[0125] In the formula, I arc-a (t), I arc-b (t) and I arc-c (t) are the average arc melting currents during the start-up, stabilization and shutdown processes of the magnesite process, t a is the start-up duration of the fused magnesium furnace, t b is the duration of the stable process of the fused magnesium furnace, t c is the duration of the shutdown process of the fused magnesium furnace, which is calculated based on the historical data of the fused magnesium furnace recorded by the enterprise; t k It is the starting time node of the entire electric melting process;

[0126] The cost model of the magnesite load is expressed as:

[0127] Carc =C in K emis +C CH +C heat (3)

[0128] In the formula, C arc is the total operating cost of the fused magnesium furnace, C in Indicates the equivalent electricity price of the electricity input into the fused magnesium furnace; K emis is the heat dissipation coefficient, which characterizes the heat loss to the air during the smelting process; C CH is the power loss, which represents the equivalent power loss caused by the thermal effect of the wire current during the transmission process; C heat Represents heat loss, which indicates the equivalent power loss caused by the heat dissipated during the natural cooling process after the entire electric melting process is completed;

[0129] The influence of magnesia production process on the scheduling process is analyzed, and the different production stages of the electric magnesium furnace are specifically analyzed. In the start-up stage, the material is expected to melt quickly to shorten the formation time of the molten pool, and the arc power of this process is required to be large and stable; the stable process is the normal production process, and the arc power needs to be maintained near a constant value to ensure a certain molten pool depth while avoiding the "burning" phenomenon; in the shutdown stage, the molten pool height is close to the furnace body height. At this time, the arc power is required to be small to ensure the constant temperature of the molten pool while avoiding the melting of the material vertical to the electrode and avoid product contamination. Therefore, the arc melting current constraint is:

[0130]

[0131] Among them, I arc-a.n ,I arc-b.n and I arc-c.n They represent the rated values ​​of arc melting current in the start-up, stabilization and shutdown stages, ε1, ε2 and ε3 represent the allowable fluctuation values ​​in the start-up, stabilization and shutdown stages, I arc-a (t), I arc-b (t) and I arc-c (t) are the average arc melting currents in the start-up, stabilization and shutdown stages respectively;

[0132] Considering that the arc melting current is difficult to measure accurately and in real time during actual operation, in addition to the arc melting current constraint, the input power constraint and voltage constraint of the electric molten magnesium furnace are set, and the expressions are as follows:

[0133] P k,min ≤P k (t)≤P k,max (5)

[0134] U k,min ≤U k (t)≤Uk,max (6)

[0135] Where P k (t) represents the electric power input to the kth electric magnesium furnace at time t, P k,min and P k,max They represent the minimum and maximum power allowed by the kth electric magnesium furnace; U k (t) represents the voltage of the kth electric magnesium furnace at time t, U k,min and U k,max They represent the minimum voltage and maximum voltage allowed by the kth electric magnesium furnace respectively;

[0136] Step 2: construct an operation cost model of the energy storage system and determine its configuration constraints and operation constraints; the configuration constraints include capacity constraints and power constraints;

[0137] In addition to the industrial (magnesium) loads that need to be regulated, when the industrial park participates in the power system demand response process, the energy storage system can participate in the unified dispatch of the power system as one of the backup loads. The energy storage system includes electric energy storage devices and thermal energy storage devices. The following will analyze its cost model, configuration and operation constraints, as well as the electrical and thermal balance constraints of the entire industrial park.

[0138] The industrial park uses two types of energy storage devices: electric energy storage devices and thermal energy storage devices. The thermal energy storage device is divided into two components: an electric boiler and a thermal storage tank. The following will conduct an operating cost modeling analysis on the three parts of the electric energy storage device, the electric boiler, and the thermal storage tank. The configuration costs of these three types of devices are not considered in this embodiment.

[0139] For electric energy storage devices, the operating costs include equipment loss costs and energy loss costs;

[0140] The calculation formula for the equipment loss cost in the first part is as follows:

[0141]

[0142] In the formula, C soc is the equipment loss cost of the electric energy storage device, is the cost price of the capacity availability of the electric energy storage device;

[0143] It is defined as the cost price of an electric energy storage device with 1kWh of available storage capacity. Its expression and related parameter calculation method are as follows:

[0144]

[0145] In the formula, C install Represents the installation cost of the electric energy storage device; C ∑ Indicates the total life cycle capacity of the electric energy storage device; CN Indicates the rated capacity of the electric energy storage device; L soc Indicates the rated life of the electric energy storage device; DOD soc Indicates the discharge depth of the electric energy storage device; the installation cost, rated capacity and rated life of the electric energy storage device are uniquely determined after the equipment is installed;

[0146] In the second part of the energy loss cost of the electric energy storage device, the three conditions of discharge condition, charging condition and energy storage condition are discussed in a classified manner. The energy loss cost of the electric energy storage device in the discharge condition is defined as the energy loss cost of supplying power to the load per unit time, and its expression is as follows:

[0147]

[0148] In the formula, is the energy loss cost of the electric energy storage device during discharge operation, Represents the output power of the electric energy storage device, K disp It represents the power loss cost coefficient when the electric energy storage device outputs power. Its physical meaning is the price of one kilowatt-hour of electricity. However, since the electricity comes from different electricity price entities such as thermal power, photovoltaic power, and wind power, a coefficient is used to represent it.

[0149] Similarly, the energy loss cost of the energy storage device under charging conditions is defined as the charging loss of the energy storage device per unit time, and its expression is as follows:

[0150]

[0151] In the formula, is the energy loss cost of the electric energy storage device under charging conditions, Represents the input power of the electric energy storage device, K char It represents the power loss cost coefficient when the electric energy storage device inputs energy. The value can be directly taken as the electricity price corresponding to the electric energy type at the time of input;

[0152] In addition, the energy loss cost of the electric energy storage device under the energy storage condition comes from the natural leakage during storage, and its expression is as follows:

[0153]

[0154] In the formula, Energy loss cost for energy storage conditions of electric energy storage devices, represents the current storage capacity of the electric energy storage device, γ represents the energy loss coefficient of the electric energy storage device when storing energy, K storeIt indicates the power loss cost coefficient when the electric energy storage device stores energy. During normal storage, the electric energy storage device will lose the stored energy at a certain rate due to leakage current, etc. The energy loss coefficient indicates how much energy (for example, 1%) of the current storage amount will be lost in a certain period of time (such as 1 hour). The cost coefficient is the conversion coefficient of how much money these lost energy are worth;

[0155] For thermal energy storage devices, the loss cost can be combined with the operating cost, so the cost model of the thermal storage tank and the electric boiler is:

[0156] C eb =C eb.tot (1-K tran ) (13)

[0157] C heat =C heat.in.loss +C heat.emis +C heat.out.loss (14)

[0158] In the formula, C eb and C heat are the operating costs of the electric boiler and the heat storage tank respectively; C eb.tot The production cost of the total amount of electric energy input to the electric boiler within a certain period of time. When the electric energy input to the electric boiler comes entirely from new energy, this item is 0; K tran is the electric heat transfer coefficient of the electric boiler; C heat.in.loss and C heat.out.loss are the heat loss costs when the heat storage tank stores and releases heat, C heat.emis The heat dissipation cost of the heat storage tank during a certain period of time;

[0159] The capacity and power constraints of the electric energy storage device are as follows:

[0160]

[0161] In the formula, is the rated capacity of the electric energy storage device configured for the kth electric fused magnesium furnace, and are the upper and lower limits of the rated capacity of the electric energy storage device configured for the kth electric magnesium furnace, which constrains the rated capacity of a single electric energy storage device. x soc The number of fused magnesium furnaces deployed in the park, is the rated power of the electric energy storage device configured for the kth electric magnesium furnace, and are the upper and lower limits of the rated power of the electric energy storage device configured for the kth electric magnesium furnace, which constrains the rated power of a single electric energy storage device. x soc.max and xsoc.min The maximum and minimum number of energy storage devices that can be configured in the entire industrial park, which constrains the range of the number of energy storage devices that can be installed in the entire industrial park;

[0162] In addition to capacity and power constraints, the operating constraints of the electric energy storage device are as follows:

[0163]

[0164] In the formula, and are the charging state parameter and discharging state parameter of the electric energy storage device configured for the kth electric magnesium furnace at time t, both of which are 0-1 variables, 0 for invalid and 1 for valid. The following example illustrates: when the charging state variable is 1, it indicates that the electric energy storage device is in the charging state in the current time period (or time); when the discharging state variable is 1, it indicates that the electric energy storage device is in the discharging state. It should be noted that for economic considerations, the electric energy storage device cannot be in the charging and discharging states at the same time, so at most only one state variable can be 1. The first expression essentially constrains the electric energy storage device from being charged and discharged at the same time; and are the charging power and discharging power of the electric energy storage device configured for the kth electric magnesium furnace at time t, Indicates the rated maximum capacity of the electric energy storage device, E soc.k.t is the energy storage capacity of the electric energy storage device configured for the kth electric molten magnesium furnace at time t. The fourth formula shows that the energy storage capacity E of the electric energy storage device configured for the kth electric molten magnesium furnace at time t soc.k.t , which is equal to the energy storage E at time (t-1) soc.k.t-1 Plus the charging power at time t And subtract the discharge power at time t The fifth formula shows that the energy storage device configured for the kth electric magnesium furnace at time t has a storage capacity E soc.k.t , cannot exceed the rated capacity of the electrical energy storage device

[0165] For thermal energy storage devices, the capacity and power constraints of each thermal energy storage device are as follows:

[0166]

[0167] Where P eb.k is the electric power of the thermal energy storage device configured for the kth electric magnesium furnace, and are the upper and lower limits of the rated power of the thermal energy storage device configured for the kth electric magnesium furnace, that is, the upper and lower limits of the rated power of the electric boiler; the electric power P of the thermal energy storage device is limited eb.k ; is the thermal power of the heat storage tank in the thermal energy storage device configured for the kth electric magnesium furnace, and are the upper and lower limits of the rated thermal power of the heat storage tank in the thermal energy storage device configured for the kth electric molten magnesium furnace, which limits the thermal power of the heat storage tank in the thermal energy storage device. is the current heat storage capacity of the heat storage tank in the thermal energy storage device configured for the kth electric magnesium furnace, and are the upper and lower limits of the rated capacity of the heat storage tank in the thermal energy storage device configured for the kth electric fused magnesium furnace; eb.max is the maximum number of configurable thermal energy storage devices, x eb is the total number of thermal energy storage devices installed;

[0168] The components of the thermal energy storage device include an electric boiler and a heat storage tank. In addition to capacity and power constraints, the operation constraints of the electric boiler are:

[0169]

[0170] In the formula, H eb.k.t is the thermal power generated by the electric boiler in the thermal energy storage device configured for the kth electric fused magnesium furnace at time t, and η is the electric heating conversion rate of the electric boiler;

[0171] The operating constraints of the thermal storage tank are as follows:

[0172]

[0173] In the formula, and are the heat storage state and heat release state of the heat storage tank in the heat storage device configured for the kth electric fused magnesium furnace at time t; and are the heat storage power and heat release power of the heat storage tank in the thermal energy storage device configured for the kth electric fused magnesium furnace at time t; S heat.k.t is the heat storage capacity of the heat storage tank in the heat storage device configured for the kth electric fused magnesium furnace at time t;

[0174] Step 3: According to the cost model of magnesite load, the operation constraints of the load model of magnesite load, and the configuration constraints and operation constraints of the energy storage system, the power balance constraints and thermal balance constraints of the industrial park are constructed;

[0175] After establishing the constraints of industrial loads and energy storage systems, the power balance constraints in the entire industrial park can be determined:

[0176]

[0177] Where P thermal is the electric energy purchased from the thermal power plant outside the industrial park at time t;PV.t is the photovoltaic power generation power at time t; P arc.k.t is the electric power consumed by the kth electric magnesium furnace at time t;

[0178] Among them, photovoltaic power generation power P PV.t The calculation of needs to take into account its uncertainty, so the photovoltaic uncertainty model is established in the form of predicted value plus random quantity, and it is used to calculate the actual photovoltaic power generation power P PV.t :

[0179]

[0180] In the formula, is the predicted value of photovoltaic power generation at time t, which is obtained by fitting based on the actual wind power data in the region; as well as is a variable with a value of 0 or 1. When P is 1, PV.t Then take the upper limit of the predicted value of photovoltaic power generation; when When P is 1, PV.t Then take the lower limit of the predicted value of photovoltaic power generation, when and At the same time, P PV.t Then take the predicted value of photovoltaic power generation; Γ is the photovoltaic uncertainty parameter; is the upward fluctuation of photovoltaic power generation, It is the downward fluctuation amount of photovoltaic power generation;

[0181] The thermodynamic balance constraints are as follows:

[0182]

[0183] In the formula, H arc.k.t is the heat generated by the arc in the kth electric magnesium furnace at time t; H load.k.t is the heat load of the kth fused magnesium furnace at time t; Formula (22) indicates that the heat generated by the electric boiler at time t plus the heat released by the heat storage tank is equal to the sum of the heat load of all fused magnesium furnaces and the heat storage tank at time t;

[0184] Step 4: Establish the objective functions of minimizing the operating cost and maximizing the consumption of new energy respectively, and use the cost model of the magnesite load established in steps 1 and 2, the load model of the magnesite load, the operating constraints of the cost model of the magnesite load and the load model of the magnesite load, the operating cost model of the energy storage system and its configuration constraints and operating constraints, the power balance constraints and thermal balance constraints of the industrial park, and the objective functions of minimizing the operating cost and maximizing the consumption of new energy as a multi-objective optimization scheduling model;

[0185] The objective function for minimizing the operating cost is initially constructed as:

[0186]

[0187] Where F is the total operating cost of the entire industrial park load, C PV and C arc They represent the operating costs of photovoltaic power generation and electric magnesium furnace (arc furnace) at time t, and They represent the operating status of photovoltaic power generation, electric boiler, heat storage tank, electric energy storage device and electric magnesium furnace (arc furnace) at time t, respectively, and the value is 0 or 1; Formula (23) represents the minimum total operating cost of the entire industrial park in 24 hours a day;

[0188] The objective function for maximizing new energy consumption is:

[0189]

[0190] Where P PV.emis is the unused photovoltaic power; P PV is the photovoltaic power generation power, P eb and P soc are the photovoltaic rates used by the electric boiler and the power storage device respectively; P arc.PV is the photovoltaic power used by the electric magnesium furnace (arc furnace), is the working state of the fused magnesium furnace at each time node, and its value is 0 or 1; Formula (24) represents the minimum cumulative abandoned light cost of the entire system in 24 hours a day;

[0191] According to the above analysis, when industrial load participates in photovoltaic consumption, it will have a certain impact on the production and operation of magnesia load. Its control cost (regulation cost) can be divided into upward regulation cost and downward regulation cost according to the power regulation direction. Among them, the upward regulation corresponding to the consumption of photovoltaic will reduce production efficiency and cause economic losses, while the downward regulation is mainly the economic loss caused by the decline in output. The expression is as follows:

[0192] C control =|C1*ΔP M *Δt| (25)

[0193]

[0194] In the formula, C control To control the cost; ΔP M is the adjustment power; Δt is the adjustment duration; C1 is the unit control cost coefficient; F P Indicates the unit load price, RMB / MWh; F c is the unit load cost, RMB / MWh; α is the percentage of electricity consumption cost in the production cost of the industrial park; ηarc For the efficiency of electricity production;

[0195] Considering the above control cost, the final objective function for minimizing the operating cost is:

[0196]

[0197] The final objective function for maximizing new energy consumption is:

[0198]

[0199] Step 5: Use the photovoltaic control strategy for industrial load consumption to obtain a preliminary load dispatching plan for the industrial park;

[0200] The load dispatching scheme of the industrial park includes photovoltaic power generation and electric energy purchased from thermal power plants allocated to different types of equipment; the different types of equipment include electric molten magnesium furnaces (arc furnaces), electric energy storage devices and thermal energy storage devices;

[0201] Taking into account the operation status of the fused magnesium furnace and the energy storage system, the corresponding photovoltaic power level to be absorbed is used in a regulation process. Figure 3 As shown, the photovoltaic control strategy for industrial load consumption is as follows:

[0202] S1: Determine the photovoltaic power generation power to be absorbed;

[0203] In this embodiment, according to Figure 4 and Figure 5 The light intensity prediction curve and photovoltaic prediction output diagram shown are combined with the objective function of maximizing the consumption of new energy to determine the photovoltaic power generation power to be consumed;

[0204] S2: Determine the absorption capacity of the molten magnesium furnace (arc furnace), the electric energy storage device and the thermal energy storage device. If there is an molten magnesium furnace (arc furnace), the electric energy storage device or the thermal energy storage device that has the ability to absorb photovoltaic power, execute S3; otherwise, terminate the absorption and execute S7;

[0205] S3: Determine the type of equipment that currently has the ability to absorb photovoltaic power;

[0206] For the three stages of the fused magnesium furnace (arc furnace), a large amount of electric energy input is required for sufficient melting during the start-up stage. Photovoltaic power can be fully absorbed in this stage, but it cannot exceed the power constraint range of the fused magnesium furnace (arc furnace); the load needs to be maintained within a certain range during the stable stage, and it has the ability to absorb photovoltaic power when the limit is not reached; the liquid level is close to the furnace mouth during the shutdown stage, the required load is small and the control is difficult, and in practice it does not have a large photovoltaic absorption capacity; if the fused magnesium furnace (arc furnace) is not started, it is also considered that it does not have the ability to absorb photovoltaic power; for electric energy storage devices and thermal energy storage devices, they are considered to have the ability to absorb photovoltaic power before the energy storage upper limit is reached; for thermal energy storage devices, the heat energy they generate is mainly supplied to the calcining furnace and the heat storage tank, so the photovoltaic absorption capacity of the electric boiler is determined by the working state of the calcining furnace or the energy storage level of the heat storage tank;

[0207] S4: Calculate the control cost of the equipment according to the equipment type;

[0208] For the molten magnesium furnace, the control cost calculation formula is used, namely, formula (25) and formula (26); for the electric energy storage device, its operating cost is its regulation cost, which is calculated using formula (7) and (10); for the thermal energy storage device, its operating cost is its regulation cost, which is calculated using formula (13) and (14);

[0209] S5: Compare the control costs of various types of equipment and select the equipment with the lowest control cost to fully absorb photovoltaic power;

[0210] It should be pointed out that there is no substantial coupling between the devices, that is, when the consumption cost of each device is not affected by the working status of other devices, the optimal control cost of each step of S4 will ensure the optimal overall control cost;

[0211] S6: Determine whether there is still photovoltaic power that needs to be absorbed. If yes, return to S1; otherwise, terminate the absorption and execute S7. At the same time, if the equipment control cost is greater than the utilization benefit after absorption after absorption according to S5, then terminate the absorption and execute S7.

[0212] S7: According to the difference between the power required by each device and the photovoltaic power generation power consumed, the power purchased by the thermal power plant of the device is obtained, and then a preliminary load dispatching plan for the industrial park is obtained;

[0213] Step 6: Based on the multi-objective optimization scheduling model, the robust stochastic optimization algorithm is used to optimize the preliminary industrial park load scheduling plan to obtain the final industrial park load scheduling plan;

[0214] The process of the robust stochastic optimization algorithm is as follows Figure 6 As shown:

[0215] ① Initialize the original problem, that is, the degree of industrial load regulation in the industrial park load scheduling plan, as well as the upper and lower bounds of the energy storage system's charging and discharging plan and the number of iterations, determine the initial operating state of the energy storage system and the fused magnesium furnace, and construct a robust optimization problem model with optimal economic performance as follows:

[0216]

[0217] In the formula, F(u,w) is the operating cost of the whole system represented by the state variables u of each device and the natural state variable w (in this formula, it refers to the photovoltaic power generation power affected by the light intensity); G(x,u,w) represents the constraints, and U and W represent the feasible domain of the state variables u and w respectively; this expression means that while satisfying the constraints in the system, the natural state variable w has the greatest impact on the system operating cost, and the optimal artificial state variable u is obtained at this time;

[0218] ② According to the photovoltaic power generation expression (21), the photovoltaic power generation uncertainty set is determined and the photovoltaic power generation strategy is initialized as W * , represents the maximum value of photovoltaic power generation, corresponding to the worst case in which new energy consumption is the most difficult to consume, and the number of iterations n is recorded as 1;

[0219] ③Introduce the dual variable λ and auxiliary variable σ to solve the relaxed minimization problem:

[0220]

[0221] Among them, i represents the number of iterations, and the optimal solution (u n ,λ n ,σ n );

[0222] ④Solve the following maximization problem:

[0223]

[0224] In the formula, there are only w sets of variables, u n With λ n It has been obtained in step ③. After calculation, the optimal solution w of this problem can be obtained n+1 , and get the corresponding objective function value F n+1 (u n+1 ,λ n+1 );

[0225] ⑤ Check whether the algorithm is finished:

[0226] If F n+1 (u n+1 ,λ n+1 )≤σ n , that is, if the pre-set conditions are met, the algorithm terminates, and the corresponding solution u n+1This is the optimal solution obtained, and the algorithm terminates; otherwise, let n = n + 1 and add the constraint F(u n ,w i )-λ n G(x,u n ,w i )≤σ, and return to step ③.

[0227] The final result is Figure 7 As shown, Figure 7 The results in the stability assessment are as follows: Figure 8 shown.

[0228] In this embodiment, an industrial load dispatching system for new energy consumption is provided, which is used to implement an industrial load dispatching method for new energy consumption, including a model and constraint building module, an industrial park load dispatching scheme solving module and an industrial park load dispatching scheme optimization module;

[0229] The model and constraint building module is used to build a multi-objective optimization scheduling model, and the target optimization scheduling model includes a cost model of magnesite load, a load model of magnesite load, an operation constraint of the cost model of magnesite load and the load model of magnesite load, an operation cost model of the energy storage system and its configuration constraint and operation constraint, an electric power balance constraint and a thermal balance constraint of the industrial park, and an objective function of minimizing the operation cost and maximizing the consumption of new energy;

[0230] The industrial park load dispatching solution module is used to obtain a preliminary industrial park load dispatching solution by utilizing the photovoltaic control strategy for industrial load consumption;

[0231] The industrial park load scheduling scheme optimization module is used to optimize the preliminary industrial park load scheduling scheme obtained based on the multi-objective optimization scheduling model using a robust stochastic optimization algorithm to obtain a final industrial park load scheduling scheme;

[0232] The load model of the magnesite load is:

[0233]

[0234] Where p(k) is the power of the kth fused magnesium furnace, k is the number of the fused magnesium furnace, and I arc-k (t) is the arc melting current of the kth electric magnesium furnace at the tth time node, t is the number of the time node, n t is the number of time nodes, U is the external voltage of the electric fused magnesium furnace, and cosφ is the power factor;

[0235] The arc melting current of the kth electric magnesium melting furnace at the tth time node is:

[0236]

[0237] In the formula, I arc-a (t), I arc-b (t) and I arc-c (t) are the average arc melting currents during the start-up, stabilization and shutdown processes of the magnesite process, t a is the start-up duration of the fused magnesium furnace, t b is the duration of the stable process of the fused magnesium furnace, t c is the duration of the shutdown process of the fused magnesium furnace, which is calculated based on the historical data of the fused magnesium furnace recorded by the enterprise; t k It is the starting time node of the entire electric melting process;

[0238] The cost model of the magnesite load is expressed as:

[0239] C arc =C in K emis +C CH +C heat (3)

[0240] In the formula, C arc is the total operating cost of the fused magnesium furnace, C in Indicates the equivalent electricity price of the electricity input into the fused magnesium furnace; K emis is the heat dissipation coefficient, which characterizes the heat loss to the air during the smelting process; C CH is the power loss, which represents the equivalent power loss caused by the thermal effect of the wire current during the transmission process; C heat Represents heat loss, which indicates the equivalent power loss caused by the heat dissipated during the natural cooling process after the entire electric melting process is completed;

[0241] The cost model of the magnesite load and the operation constraints of the load model of the magnesite load include arc melting current constraints, electric molten magnesium furnace input power constraints and voltage constraints;

[0242] The arc melting current constraint is:

[0243]

[0244] Among them, I arc-a.n ,I arc-b.n and I arc-c.n They represent the rated values ​​of arc melting current in the start-up, stabilization and shutdown stages, ε1, ε2 and ε3 represent the allowable fluctuation values ​​in the start-up, stabilization and shutdown stages, I arc-a (t), I arc-b (t) and I arc-c (t) are the average arc melting currents in the start-up, stabilization and shutdown stages respectively;

[0245] The input power constraint and voltage constraint of the fused magnesium furnace are:

[0246] P k,min ≤P k (t)≤P k,max (5)

[0247] U k,min ≤U k (t)≤U k,max (6)

[0248] Where P k (t) represents the electric power input to the kth electric magnesium furnace at time t, P k,min and P k,max They represent the minimum and maximum power allowed by the kth electric magnesium furnace; U k (t) represents the voltage of the kth electric magnesium furnace at time t, U k,min and U k,max They respectively represent the minimum voltage and maximum voltage allowed for the kth electric fused magnesium furnace.

[0249] The energy storage system includes an electric energy storage device and a thermal energy storage device, and the operation cost model of the energy storage system includes an operation cost model of the electric energy storage device and an operation cost model of the thermal energy storage device;

[0250] The operating cost model of the electric energy storage device includes two parts: equipment loss cost and energy loss cost;

[0251] The equipment loss cost of the electric energy storage device is:

[0252]

[0253] In the formula, C soc is the equipment loss cost of the electric energy storage device, is the cost price of the capacity availability of the electric energy storage device;

[0254]

[0255] In the formula, C install Represents the installation cost of the electric energy storage device; C ∑ Indicates the total life cycle capacity of the electric energy storage device; C N Indicates the rated capacity of the electric energy storage device; L soc Indicates the rated life of the electric energy storage device; DOD soc Indicates the discharge depth of the electrical energy storage device;

[0256] The energy loss cost of the electric energy storage device includes the energy loss cost under the discharge condition, the charging condition and the energy storage condition;

[0257] The energy loss cost of the electric energy storage device during discharge operation is:

[0258]

[0259] In the formula, is the energy loss cost of the electric energy storage device during discharge operation, Represents the output power of the electric energy storage device, K disp Indicates the power loss cost coefficient when the electric energy storage device outputs power;

[0260] The energy loss cost of the electric energy storage device under charging conditions is:

[0261]

[0262] In the formula, is the energy loss cost of the electric energy storage device under charging conditions, Represents the input power of the electric energy storage device, K char It represents the power loss cost coefficient when the electric energy storage device inputs energy;

[0263] The energy loss cost of the energy storage device in the energy storage condition is:

[0264]

[0265] In the formula, Energy loss cost for energy storage conditions of electric energy storage devices, represents the current storage capacity of the electric energy storage device, γ represents the energy loss coefficient of the electric energy storage device when storing energy, K store It represents the power loss cost coefficient when the electric energy storage device stores energy;

[0266] The thermal energy storage device includes an electric boiler and a heat storage tank. The operation cost model of the thermal energy storage device includes the operation cost model of the heat storage tank and the electric boiler:

[0267] C eb =C eb.tot (1-K tran ) (13)

[0268] C heat =C heat.in.loss +C heat.emis +C heat.out.loss (14)

[0269] In the formula, C eb and C heat are the operating costs of the electric boiler and the heat storage tank respectively; C eb.tot The production cost of the total amount of electric energy input to the electric boiler within a certain period of time. When the electric energy input to the electric boiler comes entirely from new energy, this item is 0; K tranis the electric heat transfer coefficient of the electric boiler; C heat.in.loss and C heat.out.loss are the heat loss costs when the heat storage tank stores and releases heat, C heat.emis It is the cost of heat dissipation when stored in the thermal storage tank within a certain period of time.

[0270] The energy storage system includes an electric energy storage device and a thermal energy storage device, and the configuration constraints of the operation cost model of the energy storage system include capacity constraints and power constraints;

[0271] The capacity and power constraints of the electric energy storage device are:

[0272]

[0273] In the formula, is the rated capacity of the electric energy storage device configured for the kth electric fused magnesium furnace, and are the upper and lower limits of the rated capacity of the electric energy storage device configured for the kth electric fused magnesium furnace; x soc The number of fused magnesium furnaces deployed in the park, is the rated power of the electric energy storage device configured for the kth electric magnesium furnace, and are the upper and lower limits of the rated power of the electric energy storage device configured for the kth electric fused magnesium furnace; soc.max and x soc.min The maximum and minimum number of electric energy storage devices that can be configured in the entire industrial park;

[0274] The operating constraints of the electric energy storage device are:

[0275]

[0276] In the formula, and are the charging state parameter and discharging state parameter of the electric energy storage device configured for the kth electric magnesium furnace at time t, both of which are 0-1 variables, 0 for invalid and 1 for valid. The following example illustrates: when the charging state variable is 1, it indicates that the electric energy storage device is in the charging state in the current time period (or time); when the discharging state variable is 1, it indicates that the electric energy storage device is in the discharging state. It should be noted that for economic considerations, the electric energy storage device cannot be in the charging and discharging states at the same time, so at most only one state variable can be 1. The first expression essentially constrains the electric energy storage device from being charged and discharged at the same time; and are the charging power and discharging power of the electric energy storage device configured for the kth electric magnesium furnace at time t, Indicates the rated maximum capacity of the electric energy storage device, E soc.k.tThe energy storage capacity of the electric energy storage device configured for the kth electric fused magnesium furnace at time t;

[0277] Thermal energy storage device capacity constraints and power constraints:

[0278]

[0279] Where P eb.k is the electric power of the thermal energy storage device configured for the kth electric magnesium furnace, and are the upper and lower limits of the rated power of the thermal energy storage device configured for the kth electric fused magnesium furnace; is the thermal power of the heat storage tank in the thermal energy storage device configured for the kth electric magnesium furnace, and are respectively the upper limit and lower limit of the rated thermal power of the heat storage tank in the thermal energy storage device configured for the kth electric fused magnesium furnace; is the current heat storage capacity of the heat storage tank in the thermal energy storage device configured for the kth electric magnesium furnace, and are the upper and lower limits of the rated capacity of the heat storage tank in the thermal energy storage device configured for the kth electric fused magnesium furnace; eb.max is the maximum number of configurable thermal energy storage devices, x eb is the total number of thermal energy storage devices installed;

[0280] The thermal energy storage device includes an electric boiler and a heat storage tank. The operation constraints of the electric boiler are:

[0281]

[0282] In the formula, H eb.k.t is the thermal power generated by the electric boiler in the thermal energy storage device configured for the kth electric fused magnesium furnace at time t, and η is the electric heating conversion rate of the electric boiler;

[0283] The operating constraints of the thermal storage tank are:

[0284]

[0285] In the formula, and are the heat storage state and heat release state of the heat storage tank in the heat storage device configured for the kth electric fused magnesium furnace at time t; and are the heat storage power and heat release power of the heat storage tank in the thermal energy storage device configured for the kth electric fused magnesium furnace at time t; S heat.k.t It is the heat storage capacity of the heat storage tank in the thermal energy storage device configured for the kth electric fused magnesium furnace at time t.

[0286] The power balance constraint of the industrial park is:

[0287]

[0288] Where P thermal is the electric energy purchased from the thermal power plant outside the industrial park at time t; PV.t is the photovoltaic power generation power at time t; P arc.k.t is the electric power consumed by the kth electric magnesium furnace at time t;

[0289]

[0290] In the formula, is the predicted value of photovoltaic power generation at time t; as well as is a variable, with a value of 0 or 1; Γ is the photovoltaic uncertainty parameter; is the upward fluctuation of photovoltaic power generation, It is the downward fluctuation amount of photovoltaic power generation;

[0291] The thermodynamic balance constraint is:

[0292]

[0293] In the formula, H arc.k.t is the heat generated by the arc in the kth electric magnesium furnace at time t; H load.k.t is the heat load of the kth electric magnesium furnace at time t.

[0294] The objective function for minimizing the operating cost is:

[0295]

[0296] Where F is the total operating cost of the entire industrial park load, C PV and C arc They represent the operating costs of photovoltaic power generation and electric magnesium furnace at time t, and Respectively represent the operating status of photovoltaic power generation, electric boiler, heat storage tank, electric energy storage device and electric magnesium furnace at time t, and the value is 0 or 1; C control To control costs:

[0297] C control =|C1*ΔP M *Δt| (25)

[0298]

[0299] Where ΔP M is the adjustment power; Δt is the adjustment duration; C1 is the unit control cost coefficient; F P Indicates the unit load price, RMB / MWh; Fc is the unit load cost; α is the percentage of electricity consumption cost in the production cost of the industrial park; η arc For the efficiency of electricity production;

[0300] The objective function for maximizing new energy consumption is:

[0301]

[0302] Where P PV.emis is the unused photovoltaic power; P PV is the photovoltaic power generation power, P eb and P soc are the photovoltaic rates used by the electric boiler and the power storage device respectively; P arc.PV is the photovoltaic power used by the electric magnesium furnace, It is the working status of the fused magnesium furnace at each time node, and its value is 0 or 1.

[0303] The photovoltaic control strategy for industrial load consumption is specifically as follows:

[0304] S1: Determine the photovoltaic power generation power to be absorbed;

[0305] S2: Determine the absorption capacity of the molten magnesium furnace, the electric energy storage device and the thermal energy storage device. If there is a molten magnesium furnace, the electric energy storage device or the thermal energy storage device that has the ability to absorb photovoltaic power, execute step 5.3; otherwise, terminate the absorption and execute step 5.7;

[0306] S3: Determine the type of equipment that currently has the ability to absorb photovoltaic power;

[0307] S4: Calculate the control cost of the equipment according to the equipment type; the equipment types include electric fused magnesium furnace, electric energy storage device and thermal energy storage device;

[0308] The control cost of the electric magnesium furnace is calculated using the calculation formula of the control cost; for the electric energy storage device, its control cost is its operating cost; for the thermal energy storage device, its control cost is its operating cost;

[0309] S5: Compare the control costs of various types of equipment and select the equipment with the lowest control cost to fully absorb photovoltaic power;

[0310] S6: Determine whether there is still photovoltaic power that needs to be absorbed. If yes, return to step S1; otherwise, terminate the absorption and execute step S7. Meanwhile, if the equipment control cost is greater than the utilization benefit after absorption according to step S5, then terminate the absorption and execute step S7.

[0311] S7: According to the difference between the power required by each device and the consumed photovoltaic power generation power, the power purchased by the thermal power plant of the device is obtained, and then a preliminary load scheduling plan for the industrial park is obtained; the industrial park load scheduling plan includes the photovoltaic power generation power allocated to different types of equipment and the power purchased by the thermal power plant.

[0312] In this embodiment, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, an industrial load scheduling method for new energy consumption is described;

[0313] In this embodiment, a computer-readable storage medium is provided, in which a computer program is stored. When the computer program is executed by a processor, the industrial load scheduling method for new energy consumption is implemented.

Claims

1. An industrial load dispatching method for new energy consumption, characterized in that: include: Constructing a cost model of magnesite load and a load model of magnesite load, and constructing operation constraints of the cost model of magnesite load and the load model of magnesite load; Construct an operating cost model for the energy storage system and determine the configuration constraints and operating constraints of the operating cost model for the energy storage system; Construct the power balance constraints and thermal balance constraints of the industrial park; Establish the objective function of minimizing the operating cost and the objective function of maximizing the consumption of new energy respectively; The established cost model of magnesite load, the load model of magnesite load, the operating constraints of the cost model of magnesite load and the load model of magnesite load, the operating cost model of energy storage system and its configuration constraints and operating constraints, the power balance constraints and thermal balance constraints of the industrial park and the objective function of minimizing operating costs and maximizing new energy consumption are used as a multi-objective optimization scheduling model; Using photovoltaic control strategies for industrial load consumption, obtain preliminary load dispatching plans for industrial parks; Based on the multi-objective optimization scheduling model, the robust stochastic optimization algorithm is used to optimize the preliminary industrial park load scheduling plan to obtain the final industrial park load scheduling plan.

2. The industrial load dispatching method for new energy consumption according to claim 1 is characterized in that: The load model of the magnesite load is: Where p(k) is the power of the kth fused magnesium furnace, k is the number of the fused magnesium furnace, and I arc-k (t) is the arc melting current of the kth electric magnesium furnace at the tth time node, t is the number of the time node, n t is the number of time nodes, U is the external voltage of the electric fused magnesium furnace, and cosφ is the power factor; The arc melting current of the kth electric magnesium melting furnace at the tth time node is: In the formula, I arc-a (t), I arc-b (t) and I arc-c (t) are the average arc melting currents during the start-up, stabilization and shutdown processes of the magnesite process, t a is the start-up duration of the fused magnesium furnace, t b is the duration of the stable process of the fused magnesium furnace, t c is the duration of the shutdown process of the fused magnesium furnace, which is calculated based on the historical data of the fused magnesium furnace recorded by the enterprise; t k It is the starting time node of the entire electric melting process; The cost model of the magnesite load is expressed as: C arc =C in K emis +C CH +C heat (3) In the formula, C arc is the total operating cost of the fused magnesium furnace, C in Indicates the equivalent electricity price of the electric fused magnesium furnace; K emis is the heat dissipation coefficient, which characterizes the heat loss to the air during the smelting process; C CH is the power loss, which represents the equivalent power loss caused by the thermal effect of the wire current during the transmission process; C heat Represents heat loss, which indicates the equivalent power loss caused by the heat dissipated during the natural cooling process after the entire electric melting process is completed; The cost model of the magnesite load and the operation constraints of the load model of the magnesite load include arc melting current constraints, electric molten magnesium furnace input power constraints and voltage constraints; The arc melting current constraint is: Among them, I arc-a.n ,I arc-b.n and I arc-c.n They represent the rated values ​​of arc melting current in the start-up, stabilization and shutdown stages, ε1, ε2 and ε3 represent the allowable fluctuation values ​​in the start-up, stabilization and shutdown stages, I arc-a (t), I arc-b (t) and I arc-c (t) are the average arc melting currents in the start-up, stabilization and shutdown stages respectively; The input power constraint and voltage constraint of the fused magnesium furnace are: P k,min ≤P k (t)≤P k,max (5) U k,min ≤U k (t)≤U k,max (6) Where P k (t) represents the electric power input to the kth electric magnesium furnace at time t, P k,min and P k,max They represent the minimum and maximum power allowed by the kth electric magnesium furnace; U k (t) represents the voltage of the kth electric magnesium furnace at time t, U k,min and U k,max They respectively represent the minimum voltage and maximum voltage allowed for the kth electric fused magnesium furnace.

3. The industrial load dispatching method for new energy consumption according to claim 2 is characterized in that: The energy storage system includes an electric energy storage device and a thermal energy storage device, and the operation cost model of the energy storage system includes an operation cost model of the electric energy storage device and an operation cost model of the thermal energy storage device; The operating cost model of the electric energy storage device includes two parts: equipment loss cost and energy loss cost; The equipment loss cost of the electric energy storage device is: In the formula, C soc is the equipment loss cost of the electric energy storage device, is the cost price of the capacity availability of the electric energy storage device; In the formula, C install Represents the installation cost of the electric energy storage device; C ∑ Indicates the total life cycle capacity of the electric energy storage device; C N Indicates the rated capacity of the electric energy storage device; L soc Indicates the rated life of the electric energy storage device; DOD soc Indicates the discharge depth of the electrical energy storage device; The energy loss cost of the electric energy storage device includes the energy loss cost under the discharge condition, the charging condition and the energy storage condition; The energy loss cost of the electric energy storage device during discharge operation is: In the formula, is the energy loss cost of the electric energy storage device during discharge operation, Represents the output power of the electric energy storage device, K disp Indicates the power loss cost coefficient when the electric energy storage device outputs power; The energy loss cost of the electric energy storage device under charging conditions is: In the formula, is the energy loss cost of the electric energy storage device under charging conditions, Represents the input power of the electric energy storage device, K char It represents the power loss cost coefficient when the electric energy storage device inputs energy; The energy loss cost of the energy storage device in the energy storage condition is: In the formula, Energy loss cost for energy storage conditions of electric energy storage devices, represents the current storage capacity of the electric energy storage device, γ represents the energy loss coefficient of the electric energy storage device when storing energy, K store It represents the power loss cost coefficient when the electric energy storage device stores energy; The thermal energy storage device includes an electric boiler and a heat storage tank. The operation cost model of the thermal energy storage device includes the operation cost model of the heat storage tank and the electric boiler: C eb =C eb.tot (1-K tran ) (13) C heat =C heat.in.loss +C heat.emis +C heat.out.loss (14) In the formula, C eb and C heat are the operating costs of the electric boiler and the heat storage tank respectively; C eb.tot The production cost of the total amount of electric energy input to the electric boiler within a certain period of time. When the electric energy input to the electric boiler comes entirely from new energy, this item is 0; K tran is the electric heat transfer coefficient of the electric boiler; C heat.in.loss and C heat.out.loss are the heat loss costs when the heat storage tank stores and releases heat, C heat.emis It is the cost of heat dissipation when stored in the thermal storage tank within a certain period of time.

4. The industrial load dispatching method for new energy consumption according to claim 3 is characterized in that: The energy storage system includes an electric energy storage device and a thermal energy storage device, and the configuration constraints of the operation cost model of the energy storage system include capacity constraints and power constraints; The capacity and power constraints of the electric energy storage device are: In the formula, is the rated capacity of the electric energy storage device configured for the kth electric fused magnesium furnace, and are the upper and lower limits of the rated capacity of the electric energy storage device configured for the kth electric fused magnesium furnace; x soc The number of fused magnesium furnaces deployed in the park, is the rated power of the electric energy storage device configured for the kth electric magnesium furnace, and are the upper and lower limits of the rated power of the electric energy storage device configured for the kth electric fused magnesium furnace; soc.max and x soc.min The maximum and minimum number of electric energy storage devices that can be configured in the entire industrial park; The operating constraints of the electric energy storage device are: In the formula, and are the charging state parameter and discharging state parameter of the electric energy storage device configured for the kth electric magnesium furnace at time t, both of which are 0-1 variables, 0 for invalid and 1 for valid. The following example illustrates: when the charging state variable is 1, it indicates that the electric energy storage device is in the charging state in the current time period (or time); when the discharging state variable is 1, it indicates that the electric energy storage device is in the discharging state. It should be noted that for economic considerations, the electric energy storage device cannot be in the charging and discharging states at the same time, so at most only one state variable can be 1. The first expression essentially constrains the electric energy storage device from being charged and discharged at the same time; and are the charging power and discharging power of the electric energy storage device configured for the kth electric magnesium furnace at time t, Indicates the rated maximum capacity of the electric energy storage device, E soc.k.t The energy storage capacity of the electric energy storage device configured for the kth electric fused magnesium furnace at time t; Thermal energy storage device capacity constraints and power constraints: Where P eb.k is the electric power of the thermal energy storage device configured for the kth electric magnesium furnace, and are the upper and lower limits of the rated power of the thermal energy storage device configured for the kth electric fused magnesium furnace; is the thermal power of the heat storage tank in the thermal energy storage device configured for the kth electric magnesium furnace, and are respectively the upper limit and lower limit of the rated thermal power of the heat storage tank in the thermal energy storage device configured for the kth electric fused magnesium furnace; is the current heat storage capacity of the heat storage tank in the thermal energy storage device configured for the kth electric magnesium furnace, and are the upper and lower limits of the rated capacity of the heat storage tank in the thermal energy storage device configured for the kth electric fused magnesium furnace; eb.max is the maximum number of configurable thermal energy storage devices, x eb is the total number of thermal energy storage devices installed; The thermal energy storage device includes an electric boiler and a heat storage tank. The operation constraints of the electric boiler are: In the formula, H eb.k.t is the thermal power generated by the electric boiler in the thermal energy storage device configured for the kth electric fused magnesium furnace at time t, and η is the electric heating conversion rate of the electric boiler; The operating constraints of the thermal storage tank are: In the formula, and are the heat storage state and heat release state of the heat storage tank in the heat storage device configured for the kth electric fused magnesium furnace at time t; and are the heat storage power and heat release power of the heat storage tank in the thermal energy storage device configured for the kth electric fused magnesium furnace at time t; S heat.k.t It is the heat storage capacity of the heat storage tank in the thermal energy storage device configured for the kth electric fused magnesium furnace at time t.

5. The industrial load dispatching method for new energy consumption according to claim 4 is characterized in that: The power balance constraint of the industrial park is: Where P thermal is the electric energy purchased from the thermal power plant outside the industrial park at time t; PV.t is the photovoltaic power generation power at time t; P arc.k.t is the electric power consumed by the kth electric magnesium furnace at time t; In the formula, is the predicted value of photovoltaic power generation at time t; and u PV.t is a variable, with a value of 0 or 1; Γ is the photovoltaic uncertainty parameter; is the upward fluctuation of photovoltaic power generation, Δ P PV.t It is the downward fluctuation amount of photovoltaic power generation; The thermodynamic balance constraint is: In the formula, H arc.k.t is the heat generated by the electric arc in the kth electric magnesium furnace at time t; H load.k.t is the heat load of the kth electric magnesium furnace at time t.

6. The industrial load dispatching method for new energy consumption according to claim 5 is characterized in that: The objective function for minimizing the operating cost is: Where F is the total operating cost of the entire industrial park load, C PV and C arc They represent the operating costs of photovoltaic power generation and electric magnesium furnace at time t, and Respectively represent the operating status of photovoltaic power generation, electric boiler, heat storage tank, electric energy storage device and electric magnesium furnace at time t, and the value is 0 or 1; C control To control costs: C control =|C1*ΔP M *Δt| (25) Where ΔP M is the adjustment power; Δt is the adjustment duration; C1 is the unit control cost coefficient; F P Indicates the unit load price, RMB / MWh; F c is the unit load cost; α is the percentage of electricity consumption cost in the production cost of the industrial park; η arc For the efficiency of electricity production; The objective function for maximizing new energy consumption is: Where P PV.emis is the unused photovoltaic power; P PV is the photovoltaic power generation power, P eb and P soc are the photovoltaic rates used by the electric boiler and the power storage device respectively; P arc.PV is the photovoltaic power used by the electric magnesium furnace, It is the working status of the fused magnesium furnace at each time node, and its value is 0 or 1.

7. The industrial load dispatching method for new energy consumption according to claim 6 is characterized in that: The photovoltaic control strategy for industrial load consumption is specifically as follows: S1: Determine the photovoltaic power generation power to be absorbed; S2: Determine the absorption capacity of the molten magnesium furnace, the electric energy storage device and the thermal energy storage device. If there is a molten magnesium furnace, the electric energy storage device or the thermal energy storage device that has the ability to absorb photovoltaic power, execute step 5.3; otherwise, terminate the absorption and execute step 5.7; S3: Determine the type of equipment that currently has the ability to absorb photovoltaic power; S4: Calculate the control cost of the equipment according to the equipment type; the equipment types include electric fused magnesium furnace, electric energy storage device and thermal energy storage device; The control cost of the electric magnesium furnace is calculated using the calculation formula of the control cost; for the electric energy storage device, its control cost is its operating cost; for the thermal energy storage device, its control cost is its operating cost; S5: Compare the control costs of various types of equipment and select the equipment with the lowest control cost to fully absorb photovoltaic power; S6: Determine whether there is still photovoltaic power that needs to be absorbed. If yes, return to step S1; otherwise, terminate the absorption and execute step S7. Meanwhile, if the equipment control cost is greater than the utilization benefit after absorption according to step S5, then terminate the absorption and execute step S7. S7: According to the difference between the power required by each device and the consumed photovoltaic power generation power, the power purchased by the thermal power plant of the device is obtained, and then a preliminary load scheduling plan for the industrial park is obtained; the industrial park load scheduling plan includes the photovoltaic power generation power allocated to different types of equipment and the power purchased by the thermal power plant.

8. An industrial load dispatching system for new energy consumption, characterized in that: include: The model and constraint building module is used to build a multi-objective optimization scheduling model, and the target optimization scheduling model includes a cost model of magnesite load, a load model of magnesite load, an operation constraint of the cost model of magnesite load and the load model of magnesite load, an operation cost model of the energy storage system and its configuration constraint and operation constraint, an electric power balance constraint and a thermal balance constraint of the industrial park, and an objective function of minimizing the operation cost and maximizing the consumption of new energy; The industrial park load dispatching solution module is used to obtain a preliminary industrial park load dispatching solution by utilizing the photovoltaic control strategy for industrial load consumption; The industrial park load scheduling scheme optimization module is used to optimize the preliminary industrial park load scheduling scheme obtained based on a multi-objective optimization scheduling model using a robust stochastic optimization algorithm to obtain a final industrial park load scheduling scheme.

9. A computer device, characterized in that: The invention comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, an industrial load scheduling method for new energy consumption is provided as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: A computer program is stored in a computer-readable storage medium. When the computer program is executed by a processor, an industrial load scheduling method for new energy consumption according to any one of claims 1 to 7 is implemented.

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