Electric smelting magnesium load peak regulation control method based on price guidance and master-slave game

Abstract

According to the fused magnesium load peak regulation control method based on the price guidance and the master-slave game, the fused magnesium load peak regulation control method based on the price guidance and the master-slave game is provided for solving the problem of how to excite enterprises to participate in peak regulation by reasonably setting compensation prices and the problem of internal influences caused by participation of fused magnesium enterprises in peak regulation. The system regulation and control center and the fused magnesium enterprise are connected through the power-standby compensation price, and the economic operation and peak regulation flexibility of the system are both considered; a thermal power-fused magnesium load peak regulation power distribution control strategy is designed, a system regulation and control center provides differentiated price compensation according to different peak regulation states, and system production scheduling is optimized; besides, in order to solve the problems of low peak regulation participation degree and low initiative of the fused magnesium enterprises, the fused magnesium enterprises are regarded as independent operators, the net income maximization of the enterprises is taken as a target, and the net income maximization modeling of the system regulation and control center and the fused magnesium enterprises is a master-slave game problem.

Description

Technical Field

[0001] The present invention belongs to the field of peak shaving control of power systems. In particular, aiming at the problems of increased peak shaving pressure on thermal power units caused by the intensified fluctuations in the balance between supply and demand due to the increasing proportion of new energy installed capacity and the insufficient regulation ability on the load side, a peak shaving control method for electrofused magnesia load based on price compensation and master-slave game is proposed. Background Art

[0002] As of the end of December 2023, the installed capacity of wind power in China has reached 470 million kilowatts, with a year-on-year growth of 19.9%. New energy power generation is gradually becoming an important pillar of the power system. However, the randomness and volatility of wind power have exacerbated the challenges of power grid supply-demand balance, resulting in an increase in the peak-valley difference of net load and presenting an inverse peak shaving characteristic, posing a severe test to the stable operation of the system. As the main peak shaving means, thermal power units on the source side are restricted by the minimum technical output, operating efficiency, etc., and it is difficult to balance safety and economy under deep peak shaving conditions. In contrast, high-energy-consuming loads on the demand side, with their advantages of large regulation capacity and fast response speed, have become potential resources to improve the new energy consumption capacity and relieve the regulation pressure of thermal power. As a typical high-energy-consuming load, the electrofused magnesia load has good adjustability and can participate in power grid peak shaving by flexibly adjusting production power. However, existing research mainly focuses on the physical regulation ability of demand-side loads, while ignoring the impact of enterprise benefits on their peak shaving enthusiasm and lacking a reasonable price compensation mechanism to balance the economic interests of the power grid and enterprises, resulting in the underutilization of the regulation potential of demand-side resources. Summary of the Invention

[0003] Aiming at the problems existing in the prior art, the purpose of the present invention is to provide a scientific, reasonable, highly applicable and effective peak shaving control method for electrofused magnesia load based on a price compensation mechanism, aiming to ensure the economy and peak shaving flexibility of the power grid, while motivating electrofused magnesia enterprises to actively participate in peak shaving and realizing the economic coordination of the interests of the power grid and enterprises.

[0004] The technical solution adopted to achieve the purpose of the present invention is: a peak shaving control method for electrofused magnesia load based on price guidance and master-slave game, which includes the following steps:

[0005] Establish an electrofused magnesia industrial load peak shaving system, and the secondary system of the electrofused magnesia industrial load peak shaving system includes a system control center and the control centers of electrofused magnesia enterprises;

[0006] Establish a master-slave game model with the system control center as the leader in this game and electrofused magnesia enterprises as the followers; the master-slave game model includes the upper-layer system operation cost, the lower-layer net income of electrofused magnesia enterprises, and operation constraint conditions; the game process of the master-slave game model includes:

[0007] The system control center calculates the system equivalent load based on the predicted wind power output of the electrofused magnesia industrial load peak shaving system, the initial output of the electrofused magnesia enterprise, and the conventionally obtained load power to evaluate the current peak shaving state;

[0008] Based on the current peak shaving state, the system control center formulates the unit generator set for the next day with the goal of minimizing the operating cost under the operating constraint conditions, and formulates a price incentive signal composed of power compensation revenue and reserve capacity compensation revenue and transmits it to the electrofused magnesia enterprise;

[0009] In response to the price incentive signal, the electrofused magnesia enterprise adjusts its next-day output plan and reserve capacity for self-supplied peak shaving with the goal of maximizing its own net revenue, and resubmits it as an electricity consumption plan to the system control center;

[0010] The system control center recalculates the operating cost according to the adjusted next-day electricity consumption plan of the electrofused magnesia enterprise, updates the price incentive signal, and sends it to the electrofused magnesia enterprise again until the optimal peak shaving state of the electrofused magnesia industrial load peak shaving system is obtained through multi-round information interaction and game.

[0011] As a preferred embodiment, the optimal peak shaving state of the electrofused magnesia industrial load peak shaving system is the equilibrium solution of the master-slave game model. The strategy set of the system control center is M = {λ t , C t v}, the revenue set is {-C up}, the strategy set of the electrofused magnesia enterprise is N = {P mg (t)}, the revenue set is {Be}, and the optimal peak shaving state is the equilibrium solution of the game model {λ * t , C t v* , P* mg (t)}, which satisfies the formula:

[0012]

[0013] In the formula, λ t represents the power compensation price for the electrofused magnesia furnace by the power system operator within the time period t; C t v represents the reserve capacity compensation price for the electrofused magnesia enterprise; C up represents the upper-layer system operating cost; P mg (t) represents the next-day output plan of the electrofused magnesia enterprise; Be represents the net revenue of the lower-layer electrofused magnesia enterprise.

[0014] As a preferred embodiment, the objective function of the upper-layer system with the goal of minimizing the operating cost includes:

[0015] minC up =C pf +C rc +C abon +C mg

[0016]

[0017] wherein, C up is the total cost of the upper-layer optimal operation of the system; C pf is the operating cost of the thermal power unit; C rc is the cost of the upper and lower reserve capacities of the thermal power unit; λ t is the power compensation price for the electric fused magnesia furnace by the power system operator at time t; C t v is the reserve capacity compensation price for the electric fused magnesia enterprise; C abon is the cost of wind curtailment; C wind is the unit cost of wind curtailment; C mg is the regulation utility cost of the electric fused magnesia enterprise; P Gj (t) is the output of the j-th thermal power unit at time t; a, b, c are the coal consumption coefficients of the thermal power unit; P coal is the unit price of the electric coal consumed by the unit; c co2 is the unit carbon capture price of the thermal power unit; β j is the carbon emission coefficient of the j-th thermal power unit; C sd is the total operation cost of the deep peak shaving of the thermal power unit; is the amount of wind curtailment of the system at time t; is the unit cost of the upper and lower reserve capacities of the j-th thermal power unit at time t; respectively represent the upper / lower reserve capacities of the j-th thermal power unit at time t; γ1, γ2 are the coefficients of the enterprise compensation utility function, P e mg is the operating power of the electric fused magnesia load in the initial state, ΔP mg (t) is the power reduction of the electric fused magnesia furnace required to provide reserve capacity;

[0018] The objective function of the electric fused magnesia enterprise with the goal of maximizing its own net income is:

[0019]

[0020] wherein, B is the profit price coefficient of magnesium product production, N is the quadratic coefficient of the enterprise operation and maintenance cost, b co2 is the unit carbon capture cost of the electric fused magnesia enterprise, β i is the carbon capture coefficient of the electric fused magnesia enterprise.

[0021] As a preferred embodiment, the constraint conditions satisfied by the electric fused aluminum enterprise include:

[0022]

[0023] Wherein, E d min is the minimum value of the daily energy consumption of the fused magnesia enterprise, and θ1-θ3 are the fused magnesia production rates corresponding to the power increase state, rated state, and decrease state.

[0024] As a preferred embodiment, the constraint conditions satisfied by the upper-layer system include:

[0025]

[0026] Wherein, P wind is the predicted value of wind power, P Gj min (t), PG j max (t) are respectively the upper and lower limits of the active power output of the jth thermal power unit at time t, are respectively the upper and lower ramp rates of the thermal power unit j, is the predicted value of the conventional load.

[0027] As a preferred embodiment, the fused magnesia industrial load peak shaving system includes thermal power units. The control strategies for the fused magnesia load of the fused magnesia enterprise to participate in peak shaving under different peak shaving operation states are as follows: when the equivalent load demand of the system is less than the down-regulation peak shaving capacity and the down-ramp capacity of the thermal power unit is insufficient, the fused magnesia load provides supplements for the system peak shaving demand and flexibility; when the equivalent load demand of the system is less than the down-regulation peak shaving capacity and the down-ramp capacity of the thermal power unit is satisfied, the fused magnesia load provides supplements for the system peak shaving demand; when the equivalent load demand of the system is greater than the down-regulation peak shaving capacity and the down-ramp capacity of the thermal power unit is insufficient, the fused magnesia load provides supplements for the system peak shaving flexibility; when the equivalent load demand of the system is greater than the up-regulation peak shaving capacity and the up-ramp capacity of the thermal power unit is insufficient, the fused magnesia load provides supplements for the system peak shaving demand and flexibility; when the equivalent load demand of the system is within the adjustable peak shaving capacity range and the ramp capacity of the thermal power unit is satisfied, the system peak shaving demand and flexibility rely only on the adjustment of the thermal power unit, and there is no need to adjust the output of the fused magnesia load; wherein, the down-regulation peak shaving capacity, up-regulation peak shaving capacity, and adjustable peak shaving capacity range of the fused magnesia industrial load peak shaving system are all pre-calibrated and obtained.

[0028] As a preferred embodiment, the fused magnesia load response model of the fused magnesia enterprise includes:

[0029] The output power of the fused magnesia furnace is expressed as:

[0030]

[0031] Wherein: P mg(t) represents the next-day output plan of the fused magnesia enterprise; is the reference operating power of the fused magnesia furnace at time t; ΔP k represents the increased (decreased) power when adjusting upward (downward) from gear k; P max 、P min are respectively the maximum and minimum stable operating powers that the fused magnesia furnace can withstand under the premise of safe operation; The state variable u t 、d t represents the 0-1 variable of the up / down adjustment gear of the fused magnesia furnace at time t. If the power is adjusted downward at time t, then d t =1, and if the power is adjusted upward, then u t =1; x k is the state of gear k. When gear k is selected, x k =1, otherwise x k =0; m and N(t) respectively represent the number of adjustment gears of the fused magnesia furnace and the number of fused magnesia furnaces that can participate in adjustment during the t period.

[0032] As a preferred embodiment, the constraint conditions of the fused magnesia furnace power model include:

[0033]

[0034]

[0035] In the formula, ω is the maximum allowable number of adjustments within a production cycle T, T u_max 、T d_max are respectively the longest continuous upward and downward adjustment times of the fused magnesia furnace power; represents the influence coefficient of the fused magnesia furnace power change on the output; A c is the output before the adjustment of the fused magnesia enterprise; A min is the lowest expected output of the fused magnesia enterprise.

[0036] On the second aspect, the present invention provides a fused magnesia load peak shaving control device based on price compensation and master-slave game, which includes:

[0037] A building module, used to build a fused magnesia industrial load peak shaving system, and the secondary system of the fused magnesia industrial load peak shaving system includes a system control center and a control center of the fused magnesia enterprise;

[0038] The game model establishment module is used to establish a master-slave game model with the system control center as the leader in this game and the fused magnesia enterprises as the followers; the master-slave game model includes the upper-layer system operation cost, the lower-layer net income of the fused magnesia enterprises, and operation constraint conditions; the game process of the master-slave game model includes: the system control center calculates the system equivalent load based on the predicted wind power output value of the wind power-fused magnesia industrial load peak shaving system, the initial output of the fused magnesia enterprises, and the conventional load power obtained in advance to evaluate the current peak shaving state; based on the current peak shaving state, the system control center formulates the unit generator sets for the next day with the goal of minimizing the operation cost under the operation constraint conditions, and formulates a price incentive signal composed of power compensation income and reserve capacity compensation income and transmits it to the fused magnesia enterprises; in response to the price incentive signal, the fused magnesia enterprises adjust their next-day output plans and reserve capacity for self-supplied peak shaving with the goal of maximizing their own net income, and resubmit them as electricity consumption plans to the system control center; the system control center recalculates the operation cost according to the adjusted next-day electricity consumption plan of the fused magnesia enterprises, updates the price incentive signal, and sends it to the fused magnesia enterprises again until the best peak shaving state of the wind power-fused magnesia industrial load peak shaving system is obtained through multiple rounds of information interaction.

[0039] Thirdly, the present invention provides a computer-readable storage medium, on which a computer program is stored. The computer program, when executed by a processor, implements a method for controlling the peak shaving of fused magnesia load based on price compensation and master-slave game as described in any one of claims 1-8.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] The present invention provides a method for controlling the peak shaving of fused magnesia load based on price guidance and master-slave game, which connects the system control center and the fused magnesia enterprises through power-reserve compensation price, taking into account both the economic operation of the system and the flexibility of peak shaving; designs a control strategy for power distribution of thermal power-fused magnesia load peak shaving considering the uncertainty of wind power, and the system control center provides differential price compensation according to different peak shaving states to optimize the system production scheduling; in addition, aiming at the problems of low participation degree and weak initiative of fused magnesia enterprises in peak shaving, the fused magnesia enterprises are regarded as independent operators, with the goal of maximizing the net income of the enterprises, to improve the enthusiasm of fused magnesia enterprises to participate in demand response. Description of the Drawings

[0042] Figure 1 It is the framework diagram of the fused magnesia load peak shaving based on price guidance in the present invention;

[0043] Figure 2 It is the control strategy diagram of the fused magnesia load peak shaving;

[0044] Figure 3Flow chart for solving the master-slave game of fused magnesia load based on price guidance;

[0045] Figure 4 Fused magnesia load regulation output diagram for 14 days;

[0046] Figure 5 Power-spare compensation price diagram within 14 days;

[0047] Figure 6 Abandoned wind power diagram within 14 days;

[0048] Figure 7 Minimum and maximum abandoned wind situation diagram within 14 days;

[0049] Figure 8 Comparison diagram of upper and lower spare capacities of system flexibility scenarios 1&4. Specific implementation manner

[0050] The present invention will be further described in detail below in conjunction with the specific implementation manner. The following embodiments are used to illustrate the present invention, but it should be understood that the protection scope of the present invention is not limited by the specific implementation manner.

[0051] As Figures 1 to 3 shown, a method for regulating and controlling the peak load of fused magnesia based on price guidance and master-slave game connects the system regulation center and fused magnesia enterprises through power-spare compensation price, taking into account the economic operation of the system and the flexibility of peak load regulation; a control strategy for power distribution of thermal power-fused magnesia load peak regulation considering the uncertainty of wind power is designed. The system regulation center provides differential price compensation according to different peak regulation states to optimize the production scheduling of the system;

[0052] In addition, aiming at the problems of low participation degree and weak initiative of fused magnesia enterprises in peak regulation, the fused magnesia enterprises are regarded as independent operators, with the goal of maximizing the net income of the enterprises, to improve the enthusiasm of fused magnesia enterprises to participate in demand response. Finally, through the analysis of the long-term scale peak regulation effect and the comparison of simulation results in different scenarios, the role of this method in taking into account the system peak regulation effect and improving the peak regulation enthusiasm of fused magnesia enterprises is verified. The specific steps are as follows:

[0053] Furthermore, the power model of the fused magnesia furnace in step 1 is specifically as follows:

[0054] The operation of the fused magnesia furnace can be divided into three stages: furnace start-up, smelting, and furnace shutdown. In the furnace start-up stage, the fused magnesia furnace heats the magnesite ore to the molten state, the electrode descends, and the arc power gradually increases; in the smelting stage, the arc power maintains the high temperature of the molten pool, and the power demand is relatively stable; in the furnace shutdown stage, the electrode power gradually decreases, and the arc power decreases with the temperature until it is turned off. The output power of the fused magnesia furnace can be expressed as:

[0055]

[0056]

[0057] In the formula: is the reference operating power of the electrofused magnesia furnace at time t; ΔP k represents the increased (decreased) power when adjusting upward (downward) from gear k; P mg (t) represents the output plan of the electrofused magnesia enterprise for the next day; P max 、P min are the maximum and minimum stable operating powers that the electrofused magnesia furnace can withstand under the premise of safe operation respectively; the state variable u t 、d t represent the 0-1 variables of the up / down adjustment gear of the electrofused magnesia furnace at time t. If the power is reduced at time t, then d t =1, if the power is increased, then u t =1; x k is the state of gear k. When gear k is selected, x k =1, otherwise x k =0; m and N(t) represent the number of adjustment gears of the electrofused magnesia furnace and the number of electrofused magnesia furnaces that can participate in adjustment at time t respectively.

[0058] Furthermore, the constraint conditions of the electrofused magnesia furnace power model in step 1 are specifically:

[0059] To ensure production safety and efficiency, it is necessary to strictly limit the adjustment times of the electrofused magnesia furnace. Constraint formula:

[0060]

[0061] In the formula: ω is the maximum allowable number of adjustments within a production cycle T.

[0062] To ensure the stability of the molten pool, it is necessary to maintain stable temperature and current. Continuous adjustment within a short period may cause fluctuations in the molten pool temperature and affect the smelting effect. Therefore, setting adjustment time constraints can avoid frequent adjustment in a short period and ensure the stability of the molten pool temperature and current. The adjustment time constraint of the electrofused magnesia furnace is:

[0063]

[0064] In the formula: T u_max 、T d_max are the longest continuous upward and downward adjustment times of the electrofused magnesia furnace power respectively.

[0065] When the electrofused magnesia enterprise participates in demand response, to ensure that the output of the enterprise does not decrease before and after participation in the adjustment, the output constraint of the electrofused magnesia enterprise is:

[0066]

[0067] In the formula, β represents the influence coefficient of the power change of the electric fused magnesia furnace on the output; A c is the output before the adjustment of the electric fused magnesia enterprise; A min is the lowest predicted output of the electric fused magnesia enterprise.

[0068] Furthermore, the master-slave game interaction between the peak shaving participants and the enterprise in step 2 is specifically as follows: The system regulation center is the leader in this game, and the electric fused magnesia enterprise is the follower to establish a master-slave game model. This game model takes into account sequentiality and dynamics. The specific game process is as follows. To simplify the formula, the two-way constraint is represented by only one formula: P d is the equivalent load demand of the system; D Prp (t) is the peak shaving demand at time t; θ mg (t) is the power of the electric fused magnesia load supply for peak shaving at time t; D Pfp (t) is the system peak shaving flexibility demand at time t; P e mg is the operating power of the electric fused magnesia load under the initial state; P G (t) is the output of the thermal power unit at time t; is the ramp constraint of the thermal power unit at time t; λt, C ν t are the power compensation and reserve compensation of the electric fused magnesia enterprise respectively; d mg is the power compensation income, D mg is the reserve capacity compensation income; P load is the output of the conventional load.

[0069] 1) The system regulation center calculates the system equivalent load based on the predicted wind power output, the initial output of the electric fused magnesia enterprise, and the conventional load power, evaluates the current peak shaving state. Subsequently, the peak shaving participant control center formulates the next-day unit power generation plan with the goal of minimizing the system operation cost by combining the system power balance constraint, operation safety constraint, and unit operation constraint, and formulates the power compensation d mg and the reserve capacity compensation D mg to form a price incentive signal and transmit it to the electric fused magnesia enterprise.

[0070] 2) The electric fused magnesia enterprise adjusts the next-day output plan P mg (t) and the reserve capacity with the goal of maximizing its own net income to obtain additional peak shaving compensation, and resubmits the adjusted demand to the peak shaving participant control center.

[0071] 3) The peak shaving participant control center calculates its own economic cost based on the received power consumption plan of the electric fused magnesia enterprise, updates the price incentive, and sends it to the electric fused magnesia enterprise again until the optimal peak shaving state is reached after multiple rounds of information interaction. Combined with the appendix Figure 3, in this embodiment, a genetic mutation bit solution algorithm is adopted for the game process of the multi-round information interaction. After each price incentive update, a population b is formed by performing mutation and crossover operations on population a, and the net income of the enterprise is recalculated. The updated output plan is solved by calling the Gurobi solver.

[0072] Furthermore, for the 2) different peak shaving operation state control strategies in step 2, ① when the system equivalent load demand is greater than the upward peak shaving capacity and the up-ramping capacity of the thermal power unit is satisfied, specifically:

[0073] When the system equivalent load demand is greater than the upward peak shaving capacity and the up-ramping capacity of the thermal power unit is satisfied, the peak shaving demand is supplied by the electrofused magnesia load:

[0074]

[0075] Furthermore, for the 2) different peak shaving operation state control strategies in step 2, ② when the system equivalent load demand is less than the upward peak shaving capacity and the up-ramping capacity of the thermal power unit is not satisfied, specifically:

[0076] When the system equivalent load demand is less than the upward peak shaving capacity and the up-ramping capacity of the thermal power unit is not satisfied, the electrofused magnesia load provides supplementation for the system peak shaving flexibility:

[0077]

[0078] Furthermore, for the 2) different peak shaving operation state control strategies in step 2, ③ when the system equivalent load demand is less than the downward peak shaving capacity and the down-ramping capacity of the thermal power unit is not satisfied, specifically:

[0079] When the system equivalent load demand is less than the downward peak shaving capacity and the down-ramping capacity of the thermal power unit is not satisfied, the electrofused magnesia load provides supplementation for the system peak shaving demand and flexibility:

[0080]

[0081] Furthermore, for the 2) different peak shaving operation state control strategies in step 2, ④ when the system equivalent load demand is less than the downward peak shaving capacity and the down-ramping capacity of the thermal power unit is satisfied, specifically:

[0082] When the system equivalent load demand is less than the downward peak shaving capacity and the down-ramping capacity of the thermal power unit is satisfied, the electrofused magnesia load provides supplementation for the system peak shaving demand:

[0083]

[0084] Furthermore, for the 2) different peak shaving operation state control strategies in step 2, ⑤ when the system equivalent load demand is greater than the downward peak shaving capacity and the down-ramping capacity of the thermal power unit is insufficient, specifically:

[0085] When the system equivalent load demand is greater than the downward peak shaving capacity and the down-ramping capacity of thermal power units is insufficient, the fused magnesia load provides supplement for the system peak shaving flexibility:

[0086]

[0087] Furthermore, for the control strategies of different peak shaving operation states in 2) of step 2, ⑥ when the system equivalent load demand is greater than the upward peak shaving capacity and the up-ramping capacity of thermal power units is insufficient, specifically:

[0088] When the system equivalent load demand is greater than the upward peak shaving capacity and the up-ramping capacity of thermal power units is insufficient, the fused magnesia load provides supplement for the system peak shaving demand and flexibility:

[0089]

[0090] Furthermore, for the control strategies of different peak shaving operation states in 2) of step 2, ⑦ when the system equivalent load demand is within the adjustable peak shaving capacity range and the ramping capacity of thermal power units is satisfied, specifically:

[0091] When the system equivalent load demand is within the adjustable peak shaving capacity range and the ramping capacity of thermal power units is satisfied, the system peak shaving demand and flexibility can rely only on the adjustment of thermal power units without adjusting the output of the fused magnesia load.

[0092] Furthermore, for the thermal power cost in the overall operation cost objective function of the upper-layer system in 1) of step 3, specifically:

[0093] The thermal power peak shaving cost model is divided into three stages: basic peak shaving, deep peak shaving without oil injection, and deep peak shaving with oil injection:

[0094]

[0095] In the formula: C Pg Coal consumption cost in the basic peak shaving stage; T N Is the total number of time periods; N G Is the total number of thermal power units; P Gj (t) is the output of unit j at time t; a, b, c are the coal consumption coefficients of thermal power units; P coal Is the unit price of thermal coal consumed by the unit; c co2 Is the unit carbon capture price of thermal power units; β j Is the carbon emission coefficient of thermal power unit j.

[0096] Thermal power unit life loss cost:

[0097]

[0098] N F,i,t =0.00577P Gj (t) 3-2.682P Gj (t) 2 +484.8P Gj (t)-8411 (16)

[0099] Where: C lifetime is the unit life loss cost of the unit; μ is the actual operation loss coefficient; C Gi is the purchase cost of the thermal power unit, which is mainly related to the unit capacity; N F,i,t is the number of rotor cracking cycles of the i-th thermal power unit at time t, which is related to the output of the thermal power unit.

[0100] C oil =P oil ·K oil (17)

[0101] Where: P oil is the unit oil price; K oil is the amount of oil used by the unit to participate in deep peak shaving.

[0102] In summary, the total operation cost of the thermal power unit during the deep peak shaving stage:

[0103] C sd =C lifetime +C oil (18)

[0104] Where, C sd is the total operation cost of the thermal power unit for deep peak shaving.

[0105] Furthermore, the upper-layer system overall operation cost objective function in 1) of step 3 is specifically:

[0106] minC up =C pf +C rc +C abon +C mg (19)

[0107]

[0108] Where, C up is the total cost of the upper-layer optimized operation of the system; C pf is the operation cost of the thermal power unit; C rc is the up and down reserve capacity cost of the thermal power unit; λ t is the power compensation price of the electric fused magnesia furnace by the power system operator at time t; C t v is the reserve capacity compensation price of the electric fused magnesia enterprise; C abon is the curtailment cost; C wind is the unit curtailment cost; The wind power curtailment volume of the system in period t; C mg is the regulation utility cost of the fused magnesia enterprise; is the unit cost of the upward and downward reserve capacities of the j-th thermal power unit in t time periods; respectively represent the upward / downward reserve capacities of the j-th thermal power unit in period t; γ1 and γ2 are the coefficients of the enterprise compensation utility function, and the utility function is usually expressed by a quadratic function or a logarithmic function. ΔP mg (t) is the power of the fused magnesia furnace that needs to be reduced to provide reserve capacity.

[0109] Furthermore, the constraint condition ① of the overall operation cost of the upper-layer system in step 3) for the operation constraints of wind power and thermal power is specifically as follows:

[0110] Wind power output constraint

[0111]

[0112] In the formula, P wind is the predicted value of wind power.

[0113] Thermal power unit output constraint:

[0114]

[0115] In the formula, P Gj min (t), P Gj max (t) are respectively the upper and lower limits of the active power output of thermal power unit j at time t.

[0116] Thermal power unit ramp rate constraint:

[0117]

[0118] In the formula, are respectively the upper and lower limit ramp rates of thermal power unit j.

[0119] Upward and downward reserve capacity constraint:

[0120]

[0121] Furthermore, the constraint condition ② of the overall operation cost of the upper-layer system in step 3) for the system operation constraint is specifically as follows:

[0122]

[0123] In the formula, is the predicted value of the conventional load.

[0124] Furthermore, the revenue objective function in the net revenue objective function of the lower-layer fused magnesia enterprise in step 3) 1) is specifically as follows:

[0125]

[0126] Among them, the product revenue is:

[0127] A t = BP mg (t) (27)

[0128] In the formula: The profit B obtained by the fused magnesia enterprise from producing fused magnesia is the profit price coefficient of the magnesia product production. Among them, factors such as raw material cost and electricity cost have been considered, and this price coefficient can be obtained by converting the profit per ton of magnesia.

[0129] The revenue of the fused magnesia enterprise participating in demand response is:

[0130]

[0131] Enterprise operation and maintenance cost:

[0132]

[0133] In the formula: N is the quadratic term coefficient of this cost.

[0134] The enterprise carbon emission cost is:

[0135]

[0136] In the formula, b co2 is the unit carbon capture cost of the fused magnesia enterprise, and β i is the carbon capture coefficient of the fused magnesia enterprise.

[0137] Furthermore, the constraint condition ③ of the overall operation cost of the upper-layer system in step 3) 2), the power constraint of the fused magnesia furnace, specifically is:

[0138]

[0139] Furthermore, the constraint condition ④ of the overall operation cost of the upper-layer system in step 3) 2), the daily output constraint of the fused magnesia enterprise, specifically is:

[0140]

[0141] In the formula, E d min is the minimum value of the daily energy consumption of the fused magnesia plant, and θ1 - θ3 are the fused magnesia production rates corresponding to the power increase state, rated state, and power decrease state.

[0142] Furthermore, the proof and solution of the game model in step 3) are specifically:

[0143] The leader-follower game model has the control center of power system peak shaving participants as the leader, and its strategy set is \(M = {\lambda t , C t v \}\), and the payoff set is \({-C up \}\); the enterprise, as the follower, has its strategy set \(N = {P mg (t) \}\), and the payoff set is \({Be \}\). Suppose is the equilibrium solution of the Stackelberg game model in this paper, then the following equation needs to be satisfied:

[0144]

[0145] In the equilibrium state, neither party of the game can obtain greater benefits by unilaterally changing its strategy. The following theorem will be used to prove the existence and uniqueness of the Stackelberg equilibrium solution.

[0146] The following will prove that the leader-follower game model proposed in this paper satisfies the above three conditions respectively:

[0147] 1) According to the constraints of the above participants, the strategy spaces of both are non-empty, bounded, closed convex sets, that is, non-empty compact convex sets.

[0148] 2) The enterprise's payoff can be expressed as:

[0149]

[0150] The results of taking the first-order derivative and the second-order derivative of its strategy set are:

[0151]

[0152] Since the parameters given in this paper are \(N>0\), \(\gamma_1>0\), \(\gamma_2>0\), so Under the given constraint conditions, when the upper-layer leader determines the compensation price strategy, the optimal strategy of the lower-layer follower is unique. By setting the first-order partial derivative to zero, the optimal strategy can be obtained. Q.E.D.

[0153] 3) Substitute a set of optimal solutions \({P mg (t) \}\) of the enterprise into the objective function of the upper-layer power system peak shaving participant control center, and then take the second-order partial derivatives of the objective function with respect to the strategies \({\lambda t , C t v \}\) respectively, and the obtained Hessian matrix is:

[0154]

[0155] The Hessian matrix is a positive definite matrix. From the determination of extreme value problems by the Hessian matrix, it can be seen that the upper-level system peak shaving control center has a unique optimal strategy, thus proved. In summary, all three determination conditions have been proved, and thus there is a unique equilibrium solution in the master-slave game model of this paper.

[0156] Step 4, analyze the effectiveness of different schemes;

[0157] To verify the effectiveness and rationality of the model, the specific conditions and parameters are as follows: Set the rated capacity of the thermal power units in the system to be 1200 MW; the installed capacity of the wind farm is 800 MW (accounting for 56% of the installed power supply), and the unit penalty cost for abandoned wind is 250 yuan / MWh. Assume that an electrofused magnesia enterprise has 2 electrofused magnesia plants, and the total load power of the enterprise is 800 MW. Through on-site research on magnesite enterprises in Haicheng, Liaoning, it is known that the high-energy-consuming load of electrofused magnesia usually operates continuously for 24 hours. Its maximum upward and downward adjustable power is set to 25% of the rated power, the scheduling period is 24 hours, the maximum number of adjustable times of the electrofused magnesia furnace within one scheduling period does not exceed 10 times, the maximum continuous upward adjustment time is 10 h, and the maximum continuous downward adjustment time does not exceed 7 h. Perform simulation analysis in the MATLAB simulation environment.

[0158] To verify the advantages of the proposed solution of the present invention, set Model 1 as the master-slave model optimization strategy proposed by the present invention, which is the coordinated peak shaving of electrofused magnesia load based on the price guidance mechanism. Model 2 is the influence of different price compensation mechanisms on system flexibility, where in Scenario 1, the demand response provided by the electrofused magnesia load is not considered; in Scenario 2, the power compensation and price compensation of the electrofused magnesia load are considered. From Figure 4 It can be seen that the electrofused magnesia load regulation effect of Model 1 is obvious within 14 days, and the following degree is better. From Figure 5 It can be seen that during the power compensation stage, the response capacity provided by the electrofused magnesia load increases, and it can prompt the electrofused magnesia load to adjust downward during the reserve compensation period, enhancing the system flexibility and peak shaving effect. From Figure 6 It can be seen that the total system peak shaving abandoned wind rate within 14 days is 5.836%, which has a better wind power consumption effect compared with the electrofused magnesia enterprise as a traditional load. Figure 7 The two days with the minimum and maximum abandoned wind rates are the 10th day and the 11th day, and the abandoned wind rates are 1.67% and 8.50% respectively, further verifying the effectiveness of the electrofused magnesia load participating in system peak shaving under the power-reserve price guidance on a long time scale. From Figure 8 It can be seen that in Scenario 2, the upper reserve capacity cost of the thermal power unit has decreased by 14% compared with Scenario 1. In addition, the flexibility of the thermal power unit has been enhanced, and more lower reserve capacity can be provided.

[0159] The embodiments of the present invention are not exhaustive and do not constitute a limitation on the scope of protection of the claims. Those skilled in the art can think of other substantially equivalent alternatives without creative labor based on the inspiration obtained from the embodiments of the present invention, and all are within the protection scope of the present invention.

Claims

1. A peak shaving control method for electrofused magnesia load based on price compensation and master-slave game, characterized in that, Including: Establish an industrial load peak shaving system for fused magnesia. The secondary system of the industrial load peak shaving system for fused magnesia includes a system control center and the control centers of fused magnesia enterprises. Taking the system control center as the leader in this game and the fused magnesia enterprises as the followers, establish a master-slave game model. The master-slave game model includes the upper-layer system operation cost, the lower-layer net income of fused magnesia enterprises, and operation constraint conditions. The game process of the master-slave game model includes: The system control center calculates the system equivalent load based on the predicted wind power output value of the industrial load peak shaving system for fused magnesia, the initial output of fused magnesia enterprises, and the conventional load power obtained in advance to evaluate the current peak shaving state. Based on the current peak shaving state, the system control center formulates the generator units for the next day with the goal of minimizing the operation cost under the operation constraint conditions, and formulates a price incentive signal composed of power compensation income and reserve capacity compensation income and transmits it to the fused magnesia enterprises. In response to the price incentive signal, the fused magnesia enterprises adjust their next-day output plans and reserve capacities for self-supplied peak shaving with the goal of maximizing their own net income and resubmit them as power consumption plans to the system control center. The system control center recalculates the operation cost according to the adjusted next-day power consumption plan of the fused magnesia enterprises, updates the price incentive signal, and sends it to the fused magnesia enterprises again until the best peak shaving state that satisfies the supply-demand balance of the industrial load peak shaving system for fused magnesia is obtained through multiple rounds of information interaction.

2. The electrofused magnesia load peak shaving control method based on price compensation and master-slave game according to claim 1, characterized in that The optimal peak shaving state of the electrofused magnesia industrial load peak shaving system is the equilibrium solution of the master-slave game model, and the strategy set of the system control center is The revenue set is {-C up}, the strategy set of the electrofused magnesia enterprise is N = {P mg (t)}, the revenue set is {Be}, and the optimal peak shaving state is The equilibrium solution of the game model, satisfying the formula: where λ t represents the power compensation price for the electrofused magnesia furnace by the power system operator during period t; represents the standby capacity compensation price for the electrofused magnesia enterprise; C up represents the upper-layer system operation cost; P mg (t) represents the output plan of the electrofused magnesia enterprise for the next day; Be represents the net income of the lower-layer electrofused magnesia enterprise.

3. The peak shaving control method for electrofused magnesia load based on price compensation and master-slave game according to claim 2, wherein, The objective function of the upper-layer system with the goal of minimizing the operation cost includes: minC up = C pf + C rc + C abon + C mg Where, C up is the total cost of the upper-layer optimized operation of the system; C pf is the operating cost of the thermal power unit; C rc is the cost of the up and down reserve capacities of the thermal power unit; λ t is the power compensation price of the electric fused magnesia furnace by the power system operator at time t; is the reserve capacity compensation price of the electric fused magnesia enterprise; C abon is the cost of wind curtailment; C wind is the unit cost of wind curtailment; C mg is the adjustment utility cost of the electric fused magnesia enterprise; P Gj (t) is the output of the j-th thermal power unit at time t; a, b, c are the coal consumption coefficients of the thermal power unit; P coal is the unit price of electricity coal consumed by the unit; c co2 is the unit carbon capture price of the thermal power unit; β j is the carbon emission coefficient of the j-th thermal power unit; C sd is the total operating cost of the deep peak shaving of the thermal power unit; is the amount of wind curtailment of the system at time t; is the unit cost of the up and down reserve capacities of the j-th thermal power unit at time t; respectively represent the up / down reserve capacities of the j-th thermal power unit at time t; γ1, γ2 are the coefficients of the enterprise compensation utility function, is the operating power under the initial state of the electric fused magnesia load, ΔP mg (t) is the power of the electric fused magnesia furnace that needs to be reduced to provide reserve capacity; The objective function of the fused magnesia enterprises with the goal of maximizing their own net income is: In the formula, B is the profit price coefficient of magnesium product production, N is the quadratic term coefficient of enterprise operation and maintenance cost, b co2 is the unit carbon capture cost of the fused magnesia enterprise, and β i is the carbon capture coefficient of the fused magnesia enterprise.

4. The method for controlling the peak shaving of the fused magnesia load based on price compensation and master-slave game according to claim 3, wherein, The constraint conditions satisfied by the fused magnesia enterprises include: In the formula, is the minimum daily energy consumption of the fused magnesia enterprise, and θ1-θ3 are the fused magnesia production rates corresponding to the power increase state, rated state, and power decrease state.

5. The electrofused magnesia load peak shaving control method based on price compensation and master-slave game according to claim 3, wherein The constraint conditions satisfied by the upper-layer system include: where P wind is the predicted value of wind power are respectively the upper and lower limits of the active power output of the j-th thermal power unit at time t are respectively the upper and lower ramp rates of the thermal power unit j is the predicted value of the conventional load 6. The electrofused magnesia load peak shaving control method based on price compensation and master-slave game according to claim 1, characterized in that The industrial load peak shaving system for fused magnesia includes thermal power units. To satisfy the supply-demand balance, the control strategies for the fused magnesia load of the fused magnesia enterprises to participate in peak shaving under different peak shaving operation states include: When the system equivalent load demand is less than the down-regulation peak shaving capacity and the down-ramping capacity of the thermal power units is insufficient, the fused magnesia load provides supplements for the system peak shaving demand and flexibility; when the system equivalent load demand is less than the down-regulation peak shaving capacity and the down-ramping capacity of the thermal power units is satisfied, the fused magnesia load provides supplements for the system peak shaving demand; when the system equivalent load demand is greater than the down-regulation peak shaving capacity and the down-ramping capacity of the thermal power units is insufficient, the fused magnesia load provides supplements for the system peak shaving flexibility; when the system equivalent load demand is greater than the up-regulation peak shaving capacity and the up-ramping capacity of the thermal power units is insufficient, the fused magnesia load provides supplements for the system peak shaving demand and flexibility; when the system equivalent load demand is within the adjustable peak shaving capacity range and the ramping capacity of the thermal power units is satisfied, the system peak shaving demand and flexibility rely only on the adjustment of the thermal power units, and there is no need to adjust the output of the fused magnesia load. Among them, the down-regulation peak shaving capacity, up-regulation peak shaving capacity, and adjustable peak shaving capacity range of the industrial load peak shaving system for fused magnesia are all calibrated and obtained in advance.

7. The electrofused magnesia load peak shaving control method based on price compensation and master-slave game according to claim 1, wherein The fused magnesia load response model of the fused magnesia enterprises includes: The output power of the fused magnesia furnace is expressed as: P min ≤P mg (t)≤P max Where: P mg (t) represents the next-day output plan of the fused magnesia enterprise; is the reference operating power of the fused magnesia furnace at time t; ΔP k represents the increased (decreased) power when adjusting upward (downward) from gear k; P max and P min are the maximum and minimum stable operating powers that the fused magnesia furnace can withstand under the premise of safe operation, respectively; the state variable u t and d t represent the 0-1 variables of the up / down adjustment gears of the fused magnesia furnace at time t. If the power is reduced at time t, then d t =1; if the power is increased, then u t =1; x k is the state of gear k. When gear k is selected, x k =1; otherwise, x k =0; m and N(t) represent the number of adjustment gears of the fused magnesia furnace and the number of fused magnesia furnaces that can participate in adjustment during the t period, respectively.

8. The method for controlling the peak shaving of the fused magnesia load based on price compensation and master-slave game according to claim 7, wherein The constraint conditions of the fused magnesia furnace power model include: Where ω is the maximum allowable number of adjustments within a production cycle T, T u_max , T d_max are the longest continuous increase and decrease times of the electrofused magnesia furnace power respectively; represents the influence coefficient of the change in the electrofused magnesia furnace power on the output; A c is the output before adjustment of the electrofused magnesia enterprise; A min is the estimated minimum output of the electrofused magnesia enterprise.

9. An electrofused magnesia load peak shaving control device based on price compensation and master-slave game, characterized in that, Including: Establishment module, used to establish an electric fused magnesia industrial load peak shaving system, the secondary system of the electric fused magnesia industrial load peak shaving system includes a system control center and a control center of the electric fused magnesia enterprise; Game model establishment module, used to establish a master-slave game model with the system control center as the leader in this game and the electric fused magnesia enterprise as the follower; The master-slave game model includes the upper-layer system operation cost, the lower-layer net income of the electric fused magnesia enterprise, and operation constraint conditions; The game process of the master-slave game model includes: the system control center calculates the system equivalent load based on the predicted wind power output value of the electric fused magnesia industrial load peak shaving system, the initial output of the electric fused magnesia enterprise, and the pre-obtained conventional load power to evaluate the current peak shaving state; based on the current peak shaving state, the system control center formulates the generator units for the next day with the goal of minimizing the operation cost under the operation constraint conditions, and formulates a price incentive signal composed of power compensation income and reserve capacity compensation income and transmits it to the electric fused magnesia enterprise; in response to the price incentive signal, the electric fused magnesia enterprise adjusts its next-day output plan and reserve capacity for its own supply peak shaving with the goal of maximizing its own net income, and resubmits it as an electricity consumption plan to the system control center; the system control center recalculates the operation cost according to the adjusted next-day electricity consumption plan of the electric fused magnesia enterprise and updates the price incentive signal and sends it to the electric fused magnesia enterprise again until the optimal peak shaving state of the electric fused magnesia industrial load peak shaving system is obtained after multiple rounds of information interaction.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements a method for controlling the electric fused magnesia load peak shaving based on price compensation and master-slave game as described in any one of claims 1-8.

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