A method, device, medium and equipment for evaluating load regulation capability of electrolytic aluminum

Abstract

The application discloses a kind of electrolytic aluminium load regulating capacity evaluation method, device, medium and equipment, the method includes: obtaining the information of electrolytic aluminium load;Equivalent steady-state model of electrolytic aluminium load is constructed based on the information of electrolytic aluminium load;Based on the equivalent steady-state model, the production state of the electrolytic aluminium load is divided, and the typical production state of the electrolytic aluminium load is obtained;Based on the historical data of the electrolytic aluminium load obtained in advance, the electricity elasticity parameter is calculated;Based on the typical production state and the electricity elasticity parameter, the cost control model of the electrolytic aluminium load is constructed;Based on the equivalent steady-state model and the electricity elasticity parameter, the electricity load regulating amount provided by the electrolytic aluminium load is calculated;Based on the electricity load regulating amount and the cost control model, the regulating capacity of the electrolytic aluminium load to power grid is evaluated.The application can effectively evaluate the regulating capacity of the electrolytic aluminium load to power grid.

Description

Technical Field

[0001] This invention relates to the field of power systems, and more particularly to a method, apparatus, medium, and equipment for assessing the load regulation capacity of electrolytic aluminum. Background Technology

[0002] Electrolytic aluminum load is one of the largest electricity-consuming industries, accounting for over 10% of total electricity consumption in some provinces. As a high-consumption load, leveraging its regulation capabilities is crucial for the flexible operation of the power grid. Due to its massive load base, even small adjustments to a single electrolytic aluminum load can significantly impact the grid's regulation resources. Therefore, assisting electrolytic aluminum loads in participating in the grid's demand response operations and, consequently, regulation is essential. This necessitates a comprehensive assessment of the costs and regulation capabilities of electrolytic aluminum load adjustments. This assessment will facilitate the development of demand response strategies by electrolytic aluminum load users and guide grid operators in the rational utilization of the adjustable capacity of electrolytic aluminum loads. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides a method, apparatus, medium, and equipment for evaluating the load regulation capability of electrolytic aluminum, which can effectively assess the load regulation capability of electrolytic aluminum on the power grid and the corresponding costs.

[0004] To achieve the above objectives, embodiments of the present invention provide a method for evaluating the load regulation capability of electrolytic aluminum, comprising:

[0005] Information on the electrolytic aluminum load is obtained; wherein the electrolytic aluminum load includes production equipment that produces aluminum using electrolysis, and power supply equipment that is compatible with the production equipment;

[0006] Based on the information about the electrolytic aluminum load, an equivalent steady-state model of the electrolytic aluminum load is constructed;

[0007] Based on the equivalent steady-state model, the production states of the electrolytic aluminum load are divided to obtain the typical production states of the electrolytic aluminum load;

[0008] Based on the historical data of the electrolytic aluminum load obtained in advance, the power consumption elasticity parameter is calculated;

[0009] Based on the typical production conditions and the power consumption flexibility parameters, a cost control model for the electrolytic aluminum load is constructed.

[0010] Based on the equivalent steady-state model and the power consumption elasticity parameters, the power consumption adjustment provided by the electrolytic aluminum load is calculated;

[0011] Based on the aforementioned electricity load regulation amount and the aforementioned cost control model, the ability of the electrolytic aluminum load to regulate the power grid is evaluated.

[0012] Furthermore, the production equipment includes several electrolytic cells, and the power supply equipment includes a DC bus.

[0013] Furthermore, the construction of an equivalent steady-state model of the electrolytic aluminum load based on the information of the electrolytic aluminum load specifically includes:

[0014] Based on the current and voltage of the DC bus, the equivalent resistance of the series electrolytic cells, and the back electromotive force of the series electrolytic cells plus the anode overvoltage and cathode overvoltage, an equivalent steady-state model of the electrolytic aluminum load is constructed.

[0015] Furthermore, the typical production state includes at least one of the following: rated production state, reduced production state, heat preservation state, and cooling state.

[0016] Furthermore, the calculation of the electrical elasticity parameter based on the pre-acquired historical data of the electrolytic aluminum load specifically includes:

[0017] The historical data is divided into days to obtain daily load data for the electrolytic aluminum load over multiple days.

[0018] The k-means clustering algorithm is used to cluster the daily load data of the multiple days to obtain clustering results; wherein, the clustering results include at least two first classes, and each first class contains daily load data of at least one day;

[0019] A second category is obtained from the at least two first categories; wherein the second category is the first category with the largest fluctuation in the included daily load data;

[0020] Based on the time-of-use pricing period, the daily load data included in the second category is divided into time-of-use load data;

[0021] Based on the time-segmented load data, calculate the average value of the peak period load data and the average value of the load data for the remaining periods;

[0022] Based on the average value of the peak load data, the average value of the load data for other time periods, and the typical production state, the electricity consumption elasticity parameter of the electrolytic aluminum load under time-of-use pricing and the critical parameter corresponding to the typical production state under time-of-use pricing are determined.

[0023] Furthermore, the construction of the cost control model for the electrolytic aluminum load based on the typical production state and the electricity consumption elasticity parameters specifically includes:

[0024] Based on the typical production state and the power consumption elasticity parameters, the production cost function, equipment loss cost function and revenue function of the electrolytic aluminum load are constructed respectively.

[0025] Based on the production cost function, equipment loss cost function, and revenue function, a cost control model for the electrolytic aluminum load is constructed.

[0026] Furthermore, the calculation of the electrical load adjustment provided by the electrolytic aluminum load based on the equivalent steady-state model and the electrical elasticity parameters specifically includes:

[0027] Based on the equivalent steady-state model, the average value of the peak load data, and the electricity elasticity parameter of the electrolytic aluminum load under time-of-use pricing, the electricity load adjustment amount is calculated.

[0028] This invention also provides an electrolytic aluminum load regulation capability assessment device, comprising:

[0029] An information acquisition module is used to acquire information about the electrolytic aluminum load; wherein, the electrolytic aluminum load includes production equipment that produces aluminum using electrolysis, and power supply equipment that is compatible with the production equipment;

[0030] An equivalent steady-state model construction module is used to construct an equivalent steady-state model of the electrolytic aluminum load based on the information of the electrolytic aluminum load.

[0031] The partitioning module is used to partition the production state of the electrolytic aluminum load based on the equivalent steady-state model, so as to obtain the typical production state of the electrolytic aluminum load.

[0032] The electrical elasticity parameter calculation module is used to calculate the electrical elasticity parameter based on the historical data of the pre-acquired electrolytic aluminum load.

[0033] The cost control model construction module is used to construct a cost control model for the electrolytic aluminum load based on the typical production state and the electricity consumption elasticity parameters.

[0034] The power load regulation calculation module is used to calculate the power load regulation provided by the electrolytic aluminum load based on the equivalent steady-state model and the power elasticity parameters.

[0035] An evaluation module is used to evaluate the ability of the electrolytic aluminum load to regulate the power grid based on the power load regulation amount and the cost control model.

[0036] This invention also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the electrolytic aluminum load regulation capability assessment method described in any of the preceding claims.

[0037] This invention also provides a computer device, including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein the processor executes the computer program to implement the steps of the electrolytic aluminum load regulation capability assessment method described in any of the preceding claims.

[0038] In summary, the present invention has the following beneficial effects:

[0039] This invention employs the following methods: First, information about the electrolytic aluminum load is acquired. Second, an equivalent steady-state model of the electrolytic aluminum load is constructed based on this information. Third, the production states of the electrolytic aluminum load are divided according to this equivalent steady-state model to obtain typical production states. Fourth, electricity consumption elasticity parameters are calculated based on pre-acquired historical data of the electrolytic aluminum load. Fifth, a cost control model for the electrolytic aluminum load is constructed based on the typical production states and the electricity consumption elasticity parameters. Sixth, the electricity load regulation provided by the electrolytic aluminum load is calculated based on the equivalent steady-state model and the electricity consumption elasticity parameters. Finally, the regulation capacity of the electrolytic aluminum load on the power grid is evaluated based on the electricity load regulation capacity and the cost control model. This invention effectively evaluates the regulation capacity of the electrolytic aluminum load on the power grid and the corresponding costs, thereby enabling the electrolytic aluminum load to better participate in the power grid's demand response operations and helping the power grid to better manage the load of the electrolytic aluminum load. Attached Figure Description

[0040] Figure 1 This is a flowchart illustrating an embodiment of the electrolytic aluminum load regulation capability assessment method provided by the present invention;

[0041] Figure 2 This is a schematic diagram of an embodiment of the electrolytic aluminum load regulation capacity assessment device provided by the present invention;

[0042] Figure 3 This is a schematic diagram of an embodiment of the clustering results of an electrolytic aluminum load regulation capability assessment method provided by the present invention;

[0043] Figure 4 This is a schematic diagram of an embodiment of a cost control model for an electrolytic aluminum load regulation capability assessment method provided by the present invention. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] See Figure 1 This is a flowchart illustrating an embodiment of the electrolytic aluminum load regulation capability assessment method provided by the present invention. The method includes steps S1 to S7, as detailed below:

[0046] S1, Obtain information on the electrolytic aluminum load; wherein, the electrolytic aluminum load includes production equipment that produces aluminum using electrolysis, and power supply equipment that is compatible with the production equipment;

[0047] S2, Based on the information of the electrolytic aluminum load, construct an equivalent steady-state model of the electrolytic aluminum load;

[0048] S3. Based on the equivalent steady-state model, the production states of the electrolytic aluminum load are divided to obtain the typical production states of the electrolytic aluminum load.

[0049] S4. Based on the historical data of the electrolytic aluminum load obtained in advance, calculate the power consumption elasticity parameter;

[0050] S5. Based on the typical production state and the power consumption flexibility parameters, construct a cost control model for the electrolytic aluminum load;

[0051] S6. Based on the equivalent steady-state model and the power consumption elasticity parameters, calculate the power consumption adjustment amount provided by the electrolytic aluminum load;

[0052] S7. Based on the power load regulation amount and the cost control model, evaluate the regulation capability of the electrolytic aluminum load on the power grid.

[0053] Preferably, the production equipment includes a plurality of electrolytic cells, and the power supply equipment includes a DC bus.

[0054] It should be noted that electrolytic cells are used to convert molten aluminum compounds into elemental aluminum. It should be understood that the production of electrolytic aluminum requires maintaining the electrolytic cell at a high temperature of 950–970°C, and controlling the thermal balance within the electrolytic cell is mainly achieved by adjusting the direct current (DC) supplied to it. Therefore, the supporting power supply equipment is primarily responsible for regulating and controlling the DC voltage and current supplied to the electrolytic cell. Once production begins, the electrolytic cell needs to maintain thermal balance, keeping the cryolite solvent in a liquid state at its core. A decrease in the supplied current means a reduction in the energy input to the electrolytic cell, which will affect the yield of electrolytic aluminum and the thermal balance. However, the electrolytic cell has significant thermal inertia, and reducing the current over a period of several minutes to three hours will not cause the cryolite to solidify. Therefore, the electrolytic aluminum load is suitable as an adjustable load for participating in grid demand response operations, and regulating the electrolytic aluminum load is feasible.

[0055] For example, the power supply equipment further includes: an AC bus, an on-load tap-changing transformer, a rectifier transformer, a self-saturating reactor, and / or a rectifier bridge.

[0056] Preferably, the step of constructing an equivalent steady-state model of the electrolytic aluminum load based on the information of the electrolytic aluminum load specifically includes:

[0057] Based on the current and voltage of the DC bus, the equivalent resistance of the series electrolytic cells, and the back electromotive force of the series electrolytic cells plus the anode overvoltage and cathode overvoltage, an equivalent steady-state model of the electrolytic aluminum load is constructed.

[0058] It should be noted that the multiple electrolytic cells in the electrolytic aluminum load are connected in series and supplied with the same DC current by the power supply equipment. Therefore, the entire electrolytic aluminum load can be equivalent to a DC load with added back electromotive force; thus, the equivalent steady-state model is constructed using the following formula:

[0059] U as =I d R as +E as

[0060]

[0061] Among them, U as I is the voltage of the DC bus. d P is the current of the DC bus. Load R is the power consumed by the electrolytic aluminum load. as E is the equivalent resistance of several electrolytic cells connected in series. as The back electromotive force of several electrolytic cells connected in series is supplemented with anode overvoltage and cathode overvoltage;

[0062] Understandably, the above formula represents the power of the electrolytic aluminum load when it is operating stably. When the electrolytic aluminum load participates in the grid's demand response service as an adjustable load, the main focus is on whether the change in the electrolytic aluminum load's power can meet the requirements of the grid's demand response service. The power of the electrolytic aluminum load can be adjusted by regulating its associated power supply equipment, thereby adjusting the voltage and current of the DC bus, and thus changing the power of the electrolytic aluminum load.

[0063] When the power of the electrolytic aluminum load is changed, the output of electrolytic aluminum will be affected. The relationship between the output of electrolytic aluminum and the current of the DC bus is modeled as follows:

[0064] Y = C Al I d η I n

[0065] Where Y represents the electrolytic aluminum output per unit time; C Al Indicates the electrochemical equivalent of aluminum; η I The electrolytic efficiency represents the load on the electrolytic aluminum; n represents the number of electrolytic cells.

[0066] When the load on the electrolytic aluminum plant changes and it reaches a steady state, its current efficiency will change with the current of the DC bus, as modeled below:

[0067]

[0068] Among them, I d0 η represents the rated current of the DC bus of the electrolytic aluminum load. I0 Indicates the rated electrolytic efficiency under electrolytic aluminum load;

[0069] In this embodiment, the equivalent resistance of the series-connected electrolytic cells is 1.26 mΩ; the back electromotive force of the series-connected electrolytic cells plus the anode overvoltage and cathode overvoltage is 336 V; the electrochemical equivalent of aluminum is 0.3358 kg / A; the number of electrolytic cells is 210; the rated current of the DC bus is 400 A; and the rated electrolysis efficiency is 93%.

[0070] Preferably, the typical production state includes at least one of the following: rated production state, reduced production state, heat preservation state, and cooling state.

[0071] It should be noted that in step S2 above, the rated production state of the electrolytic aluminum load is the operating state with the highest current efficiency designed according to the various parameters of the electrolytic cell. At this time, the current of the DC bus of the electrolytic aluminum load is the rated current, and the electrolysis efficiency is the rated electrolysis efficiency. The reduced production state of the electrolytic aluminum load is the state in which the current of the DC bus of the electrolytic aluminum load is reduced, but electrolytic aluminum can still be produced. In this state, electrolytic aluminum can still be produced, but its output will decrease due to the reduction in input energy. The current of the DC bus of the electrolytic aluminum in the heat preservation state will be lower than that in the reduced production state. In this state, normal production of electrolytic aluminum is difficult to maintain. The current supplied is mainly used for heat preservation of the electrolytic cell, keeping the solvent cryolite in a molten state and preventing it from cooling and solidifying. If the current of the DC bus continues to decrease, the electrolytic aluminum load enters a cooling state, and the cryolite in the electrolytic cell will begin to solidify, causing damage to the equipment. In summary, different typical production states of the electrolytic aluminum load can be distinguished by the critical current values ​​between different production states, as specifically modeled as follows:

[0072] I d1 =α1I d0

[0073] I d2 =α2I d0

[0074] Among them, I d1 To distinguish between the critical current value of reduced production and heat preservation states, I d2 α1 represents the minimum critical current value under heat preservation conditions, and α2 represents the critical coefficients of the two critical values.

[0075] Preferably, the calculation of the electrical elasticity parameter based on the historical data of the pre-acquired electrolytic aluminum load specifically includes:

[0076] The historical data is divided into days to obtain daily load data for the electrolytic aluminum load over multiple days.

[0077] The k-means clustering algorithm is used to cluster the daily load data of the multiple days to obtain clustering results; wherein, the clustering results include at least two first classes, and each first class contains daily load data of at least one day;

[0078] A second category is obtained from the at least two first categories; wherein the second category is the first category with the largest fluctuation in the included daily load data;

[0079] Based on the time-of-use pricing period, the daily load data included in the second category is divided into time-of-use load data;

[0080] Based on the time-segmented load data, calculate the average value of the peak period load data and the average value of the load data for the remaining periods;

[0081] Based on the average value of the peak load data, the average value of the load data for other time periods, and the typical production state, the electricity consumption elasticity parameter of the electrolytic aluminum load under time-of-use pricing and the critical parameter corresponding to the typical production state under time-of-use pricing are determined.

[0082] For example, the average value of the peak load data is calculated using the following formula:

[0083]

[0084] The average value of the load data for the remaining time periods is calculated using the following formula:

[0085]

[0086] Where γ is the proportionality coefficient, representing the proportion of the electrolytic aluminum load used for production to the total load of the electrolytic aluminum plant; P0 is the average value of the peak period load data; and P1 is the average value of the load data for other periods.

[0087] The critical load power of electrolytic aluminum under heat preservation conditions is shown in the following formula:

[0088]

[0089] Wherein, P2 represents the critical load power of the preset electrolytic aluminum load insulation state;

[0090] In this embodiment, the critical load power for electrolytic aluminum under heat preservation conditions is 252MW. The clustering results obtained from historical data are as follows: Figure 3 As shown, based on the clustering results, the calculated proportionality coefficient is 0.94, the calculated critical coefficient for distinguishing between reduced production and heat preservation states is 0.85, and the calculated critical coefficient for heat preservation and cooling states is 0.83.

[0091] Preferably, the step of constructing a cost control model for the electrolytic aluminum load based on the typical production state and the electricity consumption flexibility parameters specifically includes:

[0092] Based on the typical production state and the power consumption elasticity parameters, the production cost function, equipment loss cost function and revenue function of the electrolytic aluminum load are constructed respectively.

[0093] Based on the production cost function, equipment loss cost function, and revenue function, a cost control model for the electrolytic aluminum load is constructed.

[0094] For example, the production cost function is shown in the following formula:

[0095]

[0096] Where TC represents the total cost of electrolytic aluminum production, C e C represents the unit electricity price. s This indicates other costs required to produce one unit of electrolytic aluminum;

[0097] The equipment loss cost function is shown in the following formula: TC=C f , where C f This indicates the equipment loss cost that must be borne for the preset electrolytic aluminum load;

[0098] The profit function is shown in the following formula:

[0099] IC = p Al Y

[0100] Where IC represents the revenue from the electrolytic aluminum load, p Al This indicates the selling price per unit of aluminum;

[0101] When the electrolytic aluminum load is in the heat preservation and cooling state, there is no more electrolytic aluminum production and the revenue is 0.

[0102] The cost control model is shown in the following formula:

[0103] RC = TC - TC0 + IC0 - IC

[0104] Where TC0 represents the total cost of electrolytic aluminum under rated production conditions, and IC0 represents the revenue of electrolytic aluminum under rated production conditions.

[0105] In this embodiment, the electricity price is a time-of-use price: peak price 0.722675 yuan / kWh, flat price 0.490225 yuan / kWh, and off-peak price 0.257775 yuan / kWh; other costs are 11066.5 yuan / t; the selling price of aluminum is 18270 yuan / t; and the equipment loss cost incurred when the electrolytic aluminum load is in a cooling state is 5,000,000 yuan. The calculated cost control curve for electrolytic aluminum load adjustment under peak electricity price conditions is shown below. Figure 3 As shown.

[0106] Preferably, the step of calculating the power load adjustment provided by the electrolytic aluminum load based on the equivalent steady-state model and the power consumption elasticity parameters specifically includes:

[0107] Based on the equivalent steady-state model, the average value of the peak load data, and the electricity elasticity parameter of the electrolytic aluminum load under time-of-use pricing, the electricity load adjustment amount is calculated.

[0108] For example, the electrical load regulation amount is calculated using the following formula:

[0109]

[0110] Where dR represents the electrical load regulation provided by the electrolytic aluminum load, γ is the proportional coefficient, and P Load P0 represents the power consumed by the electrolytic aluminum load, and P0 is the average value of the peak load data.

[0111] For example, see Figure 4 By iterating through different power load adjustment amounts, the load adjustment cost of electrolytic aluminum under different adjustment amounts can be obtained. Plotting different power load adjustment amounts and load adjustment costs on a coordinate graph yields the cost control curve for electrolytic aluminum load adjustment, which is the evaluation result of electrolytic aluminum load adjustment capability considering user wishes and production status, including the cost under different adjustment capabilities of electrolytic aluminum load.

[0112] exist Figure 4 Under peak electricity pricing conditions, when the electrolytic aluminum load decreases by less than 73MW, its regulation cost is negative. This means that at this point, due to the high electricity price, producing electrolytic aluminum would actually result in a loss; therefore, reducing the load minimizes this loss, hence the regulation cost is negative. This is consistent with the phenomenon that electrolytic aluminum loads proactively reduce during peak electricity pricing. However, when the electrolytic aluminum load decreases further, its operating state changes from reduced production to heat preservation. At this point, since electrolytic aluminum production ceases, the regulation cost of the electrolytic aluminum load increases significantly. If the electrolytic aluminum load continues to decrease, it will enter a cooling state, and the regulation cost will increase significantly again.

[0113] See Figure 2 This is a schematic diagram of an embodiment of the electrolytic aluminum load regulation capability assessment device provided by the present invention.

[0114] This invention also provides an electrolytic aluminum load regulation capability assessment device, comprising:

[0115] The information acquisition module 101 is used to acquire information about the electrolytic aluminum load; wherein, the electrolytic aluminum load includes production equipment that produces aluminum using electrolysis, and power supply equipment that is matched with the production equipment;

[0116] The equivalent steady-state model construction module 102 is used to construct an equivalent steady-state model of the electrolytic aluminum load based on the information of the electrolytic aluminum load.

[0117] The partitioning module 103 is used to partition the production state of the electrolytic aluminum load based on the equivalent steady-state model to obtain the typical production state of the electrolytic aluminum load.

[0118] The electrical elasticity parameter calculation module 104 is used to calculate the electrical elasticity parameter based on the historical data of the pre-acquired electrolytic aluminum load.

[0119] The cost control model construction module 105 is used to construct a cost control model for the electrolytic aluminum load based on the typical production state and the power consumption elasticity parameter.

[0120] The power load regulation calculation module 106 is used to calculate the power load regulation provided by the electrolytic aluminum load based on the equivalent steady-state model and the power elastic parameters.

[0121] Evaluation module 107 is used to evaluate the regulation capability of the electrolytic aluminum load on the power grid based on the power load regulation amount and the cost control model.

[0122] Preferably, the production equipment includes a plurality of electrolytic cells, and the power supply equipment includes a DC bus.

[0123] It should be noted that electrolytic cells are used to convert molten aluminum compounds into elemental aluminum. It should be understood that the production of electrolytic aluminum requires maintaining the electrolytic cell at a high temperature of 950–970°C, and controlling the thermal balance within the electrolytic cell is mainly achieved by adjusting the direct current (DC) supplied to it. Therefore, the supporting power supply equipment is primarily responsible for regulating and controlling the DC voltage and current supplied to the electrolytic cell. Once production begins, the electrolytic cell needs to maintain thermal balance, keeping the cryolite solvent in a liquid state at its core. A decrease in the supplied current means a reduction in the energy input to the electrolytic cell, which will affect the yield of electrolytic aluminum and the thermal balance. However, the electrolytic cell has significant thermal inertia, and reducing the current over a period of several minutes to three hours will not cause the cryolite to solidify. Therefore, the electrolytic aluminum load is suitable as an adjustable load for participating in grid demand response operations, and regulating the electrolytic aluminum load is feasible.

[0124] For example, the power supply equipment further includes: an AC bus, an on-load tap-changing transformer, a rectifier transformer, a self-saturating reactor, and / or a rectifier bridge.

[0125] Preferably, the equivalent steady-state model construction module 102 is specifically used for:

[0126] Based on the current and voltage of the DC bus, the equivalent resistance of the series electrolytic cells, and the back electromotive force of the series electrolytic cells plus the anode overvoltage and cathode overvoltage, an equivalent steady-state model of the electrolytic aluminum load is constructed.

[0127] It should be noted that the multiple electrolytic cells in the electrolytic aluminum load are connected in series and supplied with the same DC current by the power supply equipment. Therefore, the entire electrolytic aluminum load can be equivalent to a DC load with added back electromotive force; thus, the equivalent steady-state model is constructed using the following formula:

[0128] U as =I d R as +E as

[0129]

[0130] Among them, U as I is the voltage of the DC bus. d P is the current of the DC bus. Load R is the power consumed by the electrolytic aluminum load. as E is the equivalent resistance of several electrolytic cells connected in series. as The back electromotive force of several electrolytic cells connected in series is supplemented with anode overvoltage and cathode overvoltage;

[0131] Understandably, the above formula represents the power of the electrolytic aluminum load when it is operating stably. When the electrolytic aluminum load participates in the grid's demand response service as an adjustable load, the main focus is on whether the change in the electrolytic aluminum load's power can meet the requirements of the grid's demand response service. The power of the electrolytic aluminum load can be adjusted by regulating its associated power supply equipment, thereby adjusting the voltage and current of the DC bus, and thus changing the power of the electrolytic aluminum load.

[0132] When the power of the electrolytic aluminum load is changed, the output of electrolytic aluminum will be affected. The relationship between the output of electrolytic aluminum and the current of the DC bus is modeled as follows:

[0133] Y = C Al I d η I n

[0134] Where Y represents the electrolytic aluminum output per unit time; C Al Indicates the electrochemical equivalent of aluminum; η I The electrolytic efficiency represents the load on the electrolytic aluminum; n represents the number of electrolytic cells.

[0135] When the load on the electrolytic aluminum plant changes and it reaches a steady state, its current efficiency will change with the current of the DC bus, as modeled below:

[0136]

[0137] Among them, I d0 η represents the rated current of the DC bus of the electrolytic aluminum load. I0 Indicates the rated electrolytic efficiency under electrolytic aluminum load;

[0138] In this embodiment, the equivalent resistance of the series-connected electrolytic cells is 1.26 mΩ; the back electromotive force of the series-connected electrolytic cells plus the anode overvoltage and cathode overvoltage is 336 V; the electrochemical equivalent of aluminum is 0.3358 kg / A; the number of electrolytic cells is 210; the rated current of the DC bus is 400 A; and the rated electrolysis efficiency is 93%.

[0139] Preferably, the typical production state includes at least one of the following: rated production state, reduced production state, heat preservation state, and cooling state.

[0140] It should be noted that in step S2 above, the rated production state of the electrolytic aluminum load is the operating state with the highest current efficiency designed according to the various parameters of the electrolytic cell. At this time, the current of the DC bus of the electrolytic aluminum load is the rated current, and the electrolysis efficiency is the rated electrolysis efficiency. The reduced production state of the electrolytic aluminum load is the state in which the current of the DC bus of the electrolytic aluminum load is reduced, but electrolytic aluminum can still be produced. In this state, electrolytic aluminum can still be produced, but its output will decrease due to the reduction in input energy. The current of the DC bus of the electrolytic aluminum in the heat preservation state will be lower than that in the reduced production state. In this state, normal production of electrolytic aluminum is difficult to maintain. The current supplied is mainly used for heat preservation of the electrolytic cell, keeping the solvent cryolite in a molten state and preventing it from cooling and solidifying. If the current of the DC bus continues to decrease, the electrolytic aluminum load enters a cooling state, and the cryolite in the electrolytic cell will begin to solidify, causing damage to the equipment. In summary, different typical production states of the electrolytic aluminum load can be distinguished by the critical current values ​​between different production states, as specifically modeled as follows:

[0141] I d1 =α1I d0

[0142] I d2 =α2I d0

[0143] Among them, I d1 To distinguish between the critical current value of reduced production and heat preservation states, I d2 α1 represents the minimum critical current value under heat preservation conditions, and α2 represents the critical coefficients of the two critical values.

[0144] Preferably, the electrical elasticity parameter calculation module 104 is specifically used for:

[0145] The historical data is divided into days to obtain daily load data for the electrolytic aluminum load over multiple days.

[0146] The k-means clustering algorithm is used to cluster the daily load data of the multiple days to obtain clustering results; wherein, the clustering results include at least two first classes, and each first class contains daily load data of at least one day;

[0147] A second category is obtained from the at least two first categories; wherein the second category is the first category with the largest fluctuation in the included daily load data;

[0148] Based on the time-of-use pricing period, the daily load data included in the second category is divided into time-of-use load data;

[0149] Based on the time-segmented load data, calculate the average value of the peak period load data and the average value of the load data for the remaining periods;

[0150] Based on the average value of the peak load data, the average value of the load data for other time periods, and the typical production state, the electricity consumption elasticity parameter of the electrolytic aluminum load under time-of-use pricing and the critical parameter corresponding to the typical production state under time-of-use pricing are determined.

[0151] For example, the average value of the peak load data is calculated using the following formula:

[0152]

[0153] The average value of the load data for the remaining time periods is calculated using the following formula:

[0154]

[0155] Where γ is the proportionality coefficient, representing the proportion of the electrolytic aluminum load used for production to the total load of the electrolytic aluminum plant; P0 is the average value of the peak period load data; and P1 is the average value of the load data for other periods.

[0156] The critical load power of electrolytic aluminum under heat preservation conditions is shown in the following formula:

[0157]

[0158] Wherein, P2 represents the critical load power of the preset electrolytic aluminum load insulation state;

[0159] In this embodiment, the critical load power for electrolytic aluminum under heat preservation conditions is 252MW. The clustering results obtained from historical data are as follows: Figure 3 As shown, based on the clustering results, the calculated proportionality coefficient is 0.94, the calculated critical coefficient for distinguishing between reduced production and heat preservation states is 0.85, and the calculated critical coefficient for heat preservation and cooling states is 0.83.

[0160] Preferably, the cost control model construction module 105 is specifically used for:

[0161] Based on the typical production state and the power consumption elasticity parameters, the production cost function, equipment loss cost function and revenue function of the electrolytic aluminum load are constructed respectively.

[0162] Based on the production cost function, equipment loss cost function, and revenue function, a cost control model for the electrolytic aluminum load is constructed.

[0163] For example, the production cost function is shown in the following formula:

[0164]

[0165] Where TC represents the total cost of electrolytic aluminum production, C e C represents the unit electricity price. s This indicates other costs required to produce one unit of electrolytic aluminum;

[0166] The equipment loss cost function is shown in the following formula: TC=C f , where C f This indicates the equipment loss cost that must be borne for the preset electrolytic aluminum load;

[0167] The profit function is shown in the following formula:

[0168] IC = p Al Y

[0169] Where IC represents the revenue from the electrolytic aluminum load, p Al This indicates the selling price per unit of aluminum;

[0170] When the electrolytic aluminum load is in the heat preservation and cooling state, there is no more electrolytic aluminum production and the revenue is 0.

[0171] The cost control model is shown in the following formula:

[0172] RC = TC - TC0 + IC0 - IC

[0173] Where TC0 represents the total cost of electrolytic aluminum under rated production conditions, and IC0 represents the revenue of electrolytic aluminum under rated production conditions.

[0174] In this embodiment, the electricity price is a time-of-use price: peak price 0.722675 yuan / kWh, flat price 0.490225 yuan / kWh, and off-peak price 0.257775 yuan / kWh; other costs are 11066.5 yuan / t; the selling price of aluminum is 18270 yuan / t; and the equipment loss cost incurred when the electrolytic aluminum load is in a cooling state is 5,000,000 yuan. The calculated cost control curve for electrolytic aluminum load adjustment under peak electricity price conditions is shown below. Figure 3 As shown.

[0175] Preferably, the power load regulation calculation module 106 is specifically used for:

[0176] Based on the equivalent steady-state model, the average value of the peak load data, and the electricity elasticity parameter of the electrolytic aluminum load under time-of-use pricing, the electricity load adjustment amount is calculated.

[0177] For example, the electrical load regulation amount is calculated using the following formula:

[0178]

[0179] Where dR represents the electrical load regulation provided by the electrolytic aluminum load, γ is the proportional coefficient, and P Load P0 represents the power consumed by the electrolytic aluminum load, and P0 is the average value of the peak load data.

[0180] For example, see Figure 4 By iterating through different power load adjustment amounts, the load adjustment cost of electrolytic aluminum under different adjustment amounts can be obtained. Plotting different power load adjustment amounts and load adjustment costs on a coordinate graph yields the cost control curve for electrolytic aluminum load adjustment, which is the evaluation result of electrolytic aluminum load adjustment capability considering user wishes and production status, including the cost under different adjustment capabilities of electrolytic aluminum load.

[0181] exist Figure 4 Under peak electricity pricing conditions, when the electrolytic aluminum load decreases by less than 73MW, its regulation cost is negative. This means that at this point, due to the high electricity price, producing electrolytic aluminum would actually result in a loss; therefore, reducing the load minimizes this loss, hence the regulation cost is negative. This is consistent with the phenomenon that electrolytic aluminum loads proactively reduce during peak electricity pricing. However, when the electrolytic aluminum load decreases further, its operating state changes from reduced production to heat preservation. At this point, since electrolytic aluminum production ceases, the regulation cost of the electrolytic aluminum load increases significantly. If the electrolytic aluminum load continues to decrease, it will enter a cooling state, and the regulation cost will increase significantly again.

[0182] This invention also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the electrolytic aluminum load regulation capability assessment method described in any of the preceding claims.

[0183] This invention also provides a computer device, including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein the processor executes the computer program to implement the steps of the electrolytic aluminum load regulation capability assessment method described in any of the preceding claims.

[0184] The computer device in this embodiment includes a processor, a memory, and a computer program stored in the memory and executable on the processor, such as an electrolytic aluminum load regulation capability assessment program. When the processor executes the computer program, it implements the steps in the various embodiments of the electrolytic aluminum load regulation capability assessment method described above, for example... Figure 1 The steps S1 to S7 are shown. Alternatively, when the processor executes the computer program, it implements the functions of each module / unit in the above-described device embodiments, such as steps 101 to 107.

[0185] For example, the computer program may be divided into one or more modules / units, which are stored in the memory and executed by the processor to complete the present invention. The one or more modules / units may be a series of computer program instruction segments capable of performing a specific function, which describe the execution process of the computer program in the computer device.

[0186] The computer device may be a desktop computer, laptop, handheld computer, or cloud server, etc. The computer device may include, but is not limited to, a processor and memory. Those skilled in the art will understand that the schematic diagram is merely an example of a computer device and does not constitute a limitation on the computer device. It may include more or fewer components than illustrated, or combine certain components, or different components. For example, the computer device may also include input / output devices, network access devices, buses, etc.

[0187] The processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or any conventional processor. The processor is the control center of the computer device, connecting various parts of the computer device via various interfaces and lines.

[0188] The memory can be used to store the computer programs and / or modules. The processor implements various functions of the computer device by running or executing the computer programs and / or modules stored in the memory and by calling data stored in the memory. The memory may mainly include a program storage area and a data storage area. The program storage area may store the operating system, at least one application program required for a function (such as sound playback function, image playback function, etc.), etc.; the data storage area may store data created according to the use of the mobile phone (such as audio data, phonebook, etc.). In addition, the memory may include high-speed random access memory, and may also include non-volatile memory, such as hard disk, memory, plug-in hard disk, smart media card (SMC), secure digital (SD) card, flash card, at least one disk storage device, flash memory device, or other volatile solid-state storage device.

[0189] Wherein, if the modules / units integrated into the computer device are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments of the present invention can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc.

[0190] In summary, the present invention has the following beneficial effects:

[0191] This invention employs the following methods: First, information about the electrolytic aluminum load is acquired. Second, an equivalent steady-state model of the electrolytic aluminum load is constructed based on this information. Third, the production states of the electrolytic aluminum load are divided according to this equivalent steady-state model to obtain typical production states. Fourth, electricity consumption elasticity parameters are calculated based on pre-acquired historical data of the electrolytic aluminum load. Fifth, a cost control model for the electrolytic aluminum load is constructed based on the typical production states and the electricity consumption elasticity parameters. Sixth, the electricity load regulation provided by the electrolytic aluminum load is calculated based on the equivalent steady-state model and the electricity consumption elasticity parameters. Finally, the regulation capacity of the electrolytic aluminum load on the power grid is evaluated based on the electricity load regulation capacity and the cost control model. This invention effectively evaluates the regulation capacity of the electrolytic aluminum load on the power grid and the corresponding costs, thereby enabling the electrolytic aluminum load to better participate in the power grid's demand response operations and helping the power grid to better manage the load of the electrolytic aluminum load.

[0192] Through the above description of the embodiments, those skilled in the art can clearly understand that the present invention can be implemented by means of software plus necessary hardware platforms, and of course, it can also be implemented entirely by hardware. Based on this understanding, all or part of the technical solution of the present invention that contributes to the background art can be embodied in the form of a software product. This computer software product can be stored in a storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in various embodiments or some parts of the embodiments of the present invention.

[0193] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A method for evaluating the load regulation capability of electrolytic aluminum, characterized in that, include: Information on the electrolytic aluminum load is obtained; wherein the electrolytic aluminum load includes production equipment that produces aluminum using electrolysis, and power supply equipment that is compatible with the production equipment; Based on the information about the electrolytic aluminum load, an equivalent steady-state model of the electrolytic aluminum load is constructed; Based on the equivalent steady-state model, the production states of the electrolytic aluminum load are divided to obtain the typical production states of the electrolytic aluminum load; Based on the historical data of the electrolytic aluminum load obtained in advance, the power consumption elasticity parameter is calculated; Based on the typical production conditions and the power consumption flexibility parameters, a cost control model for the electrolytic aluminum load is constructed. Based on the equivalent steady-state model and the power consumption elasticity parameters, the power consumption adjustment provided by the electrolytic aluminum load is calculated; Based on the aforementioned electricity load regulation amount and the aforementioned cost control model, the ability of the electrolytic aluminum load to regulate the power grid is evaluated. The step of calculating the electricity consumption elasticity parameter based on the pre-acquired historical data of the electrolytic aluminum load specifically includes: dividing the historical data into daily units to obtain daily load data of the electrolytic aluminum load over multiple days; using a k-means clustering algorithm to cluster the daily load data of the multiple days to obtain clustering results; wherein the clustering results include at least two first classes, each containing daily load data of at least one day; finding a second class from the at least two first classes; wherein the second class is the first class containing the largest fluctuation in daily load data; dividing the daily load data contained in the second class into time-of-use load data based on the time period of the time-of-use electricity price; calculating the average value of the peak period load data and the average value of the load data of other periods based on the time-of-use load data; and determining the electricity consumption elasticity parameter of the electrolytic aluminum load under the time-of-use electricity price and the critical parameter corresponding to the typical production state under the time-of-use electricity price based on the average value of the peak period load data, the average value of the load data of other periods, and the typical production state.

2. The method for evaluating the load regulation capability of electrolytic aluminum as described in claim 1, characterized in that, The production equipment includes several electrolytic cells, and the power supply equipment includes a DC bus.

3. The method for evaluating the load regulation capability of electrolytic aluminum as described in claim 2, characterized in that, The construction of an equivalent steady-state model of the electrolytic aluminum load based on the information of the electrolytic aluminum load specifically includes: Based on the current and voltage of the DC bus, the equivalent resistance of the series electrolytic cells, and the back electromotive force of the series electrolytic cells plus the anode overvoltage and cathode overvoltage, an equivalent steady-state model of the electrolytic aluminum load is constructed.

4. The method for evaluating the load regulation capability of electrolytic aluminum as described in claim 1, characterized in that, The typical production state includes at least one of the following: rated production state, reduced production state, heat preservation state, and cooling state.

5. The method for evaluating the load regulation capability of electrolytic aluminum as described in claim 1, characterized in that, The cost control model for the electrolytic aluminum load, constructed based on the typical production state and the electricity consumption elasticity parameters, specifically includes: Based on the typical production state and the power consumption elasticity parameters, the production cost function, equipment loss cost function and revenue function of the electrolytic aluminum load are constructed respectively. Based on the production cost function, equipment loss cost function, and revenue function, a cost control model for the electrolytic aluminum load is constructed.

6. The method for evaluating the load regulation capability of electrolytic aluminum as described in claim 1, characterized in that, The calculation of the electricity load regulation provided by the electrolytic aluminum load based on the equivalent steady-state model and the electricity consumption elasticity parameters specifically includes: Based on the equivalent steady-state model, the average value of the peak load data, and the electricity elasticity parameter of the electrolytic aluminum load under time-of-use pricing, the electricity load adjustment amount is calculated.

7. A device for evaluating the load regulation capacity of electrolytic aluminum, characterized in that, include: An information acquisition module is used to acquire information about the electrolytic aluminum load; wherein, the electrolytic aluminum load includes production equipment that produces aluminum using electrolysis, and power supply equipment that is compatible with the production equipment; An equivalent steady-state model construction module is used to construct an equivalent steady-state model of the electrolytic aluminum load based on the information of the electrolytic aluminum load. The partitioning module is used to partition the production state of the electrolytic aluminum load based on the equivalent steady-state model, so as to obtain the typical production state of the electrolytic aluminum load. The electrical elasticity parameter calculation module is used to calculate the electrical elasticity parameter based on the historical data of the pre-acquired electrolytic aluminum load. The cost control model construction module is used to construct a cost control model for the electrolytic aluminum load based on the typical production state and the electricity consumption elasticity parameters. The power load regulation calculation module is used to calculate the power load regulation provided by the electrolytic aluminum load based on the equivalent steady-state model and the power elasticity parameters. An evaluation module is used to evaluate the ability of the electrolytic aluminum load to regulate the power grid based on the power load regulation amount and the cost control model. The step of calculating the electricity consumption elasticity parameter based on the pre-acquired historical data of the electrolytic aluminum load specifically includes: dividing the historical data into daily units to obtain daily load data of the electrolytic aluminum load over multiple days; using a k-means clustering algorithm to cluster the daily load data of the multiple days to obtain clustering results; wherein the clustering results include at least two first classes, each containing daily load data of at least one day; finding a second class from the at least two first classes; wherein the second class is the first class containing the largest fluctuation in daily load data; dividing the daily load data contained in the second class into time-of-use load data based on the time period of the time-of-use electricity price; calculating the average value of the peak period load data and the average value of the load data of other periods based on the time-of-use load data; and determining the electricity consumption elasticity parameter of the electrolytic aluminum load under the time-of-use electricity price and the critical parameter corresponding to the typical production state under the time-of-use electricity price based on the average value of the peak period load data, the average value of the load data of other periods, and the typical production state.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by the processor, the program implements the electrolytic aluminum load regulation capability assessment method as described in any one of claims 1 to 6.

9. A computer device, characterized in that, The device includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein the processor, when executing the computer program, implements the electrolytic aluminum load regulation capability assessment method as described in any one of claims 1 to 6.

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