Energy storage charging and discharging control method, device, storage medium and equipment

Abstract

The present invention provides a method, device, storage medium and equipment for energy storage charge and discharge control, including: obtaining the user historical load demand curve of the energy storage system according to the historical demand of the power grid inlet and outlet lines and the historical demand of the energy storage inlet and outlet lines in a preset time period; predicting the maximum demand of the user in the current month according to the user historical load demand curve of the energy storage system; adjusting the charging power or discharging power of the energy storage system in the charging and discharging time period according to the maximum demand of the current month and the real-time active power of the power grid inlet and outlet lines in each charging and discharging time period. The charging and discharging strategy of the energy storage control system is adjusted by combining the time-of-use electricity price with the predicted user demand, fully considering the factors of user demand and energy storage system load on the basis of minimizing the user's electricity cost, so that the electric energy stored in the energy storage system can be used with the highest efficiency.

Description

Technical Field

[0001] The present invention relates to the field of power grids, and in particular to a method, device, storage medium and equipment for controlling energy storage charging and discharging. Background Art

[0002] A grid energy storage system refers to a device installed in a grid system for storing electrical energy. The grid energy storage system can store electrical energy in other forms and release it when needed to balance electricity supply and demand and improve the reliability and efficiency of the grid.

[0003] There are various charging and discharging adjustment strategies for existing energy storage systems, including but not limited to adjusting the charging and discharging of energy storage systems according to time-of-use electricity prices, such as charging during valley periods when electricity prices are lower and discharging during peak periods when electricity prices are higher; managing the charging and discharging of energy storage systems according to user demand, such as purchasing electricity from the grid during periods of low user demand and reducing the power drawn from the grid by discharging the energy storage system during periods of high user demand; managing the charging and discharging of energy storage systems according to the battery status of the energy storage system, such as starting charging when the battery's state of charge is below a certain threshold and starting discharging when the battery's state of charge is above a certain threshold.

[0004] The linear energy storage system charging and discharging strategy is mostly adjusted according to the time-of-use electricity price. In order for users to use electricity at the lowest price possible, the energy storage system needs to be fully discharged during the peak electricity price period and fully charged during the valley electricity price period. However, due to the instability of user load, if the user load of the energy storage system is too low during the set discharge period, the discharge of the energy storage system will cause the user load value to be lower than the lower limit of the load power, and even power reverse transmission will occur. Similarly, if the user load of the energy storage system is too high during the set charging period, the charging of the energy storage system may cause the maximum demand value to increase abnormally, resulting in an increase in the user's basic electricity fee.

[0005] In addition, if the charging and discharging strategy of the energy storage system is adjusted according to the maximum demand of the user, the maximum demand can only be continuously increased according to the maximum demand recorded by the maximum demand meter installed by the power supply department; for example, taking 15 minutes as a time unit, the power consumption in the first 15-minute time period is taken as the maximum demand. If the power consumption in the next time period is greater than the current maximum demand, the maximum demand is updated with the power consumption in the next time period. If the power consumption in the next time period is less than the current maximum demand, the maximum demand is not updated. The above maximum demand is limited by the total capacity of the transformer. The maximum demand is lower than a certain proportion of the total capacity of the transformer, or lower than a certain proportion of the total capacity of the transformer and the high-voltage motor that does not pass through the transformer, which is equivalent to the lower limit of the load power. The maximum demand is obtained by the sum of the capacities at the preset proportion. In this case, the gap between the actual power load and the contracted power load is large. Whether the actual power load is too high or too low, the user's electricity cost will increase accordingly.

[0006] From the above analysis, the existing energy storage system charging and discharging is simply discharging during peak electricity price periods and charging during valley electricity price periods, without considering the user demand and load of the energy storage system. This can easily cause the energy storage system charging and discharging strategy to be inconsistent with actual user demand, resulting in the inability to efficiently utilize the electricity in the energy storage system. Summary of the invention

[0007] Based on this, the present invention provides an energy storage charging and discharging method, device, storage medium and equipment, which adjust the charging and discharging strategy of the energy storage control system by combining the time-of-use electricity price with the predicted user demand, and fully consider the factors of user demand and energy storage system load on the basis of minimizing the user's electricity cost, so that the electric energy stored in the energy storage system can be used with the highest efficiency, and can avoid the situation of power reverse caused by the user's total load being too high or too low, which has positive significance for the safe and economical operation of the user's energy storage system.

[0008] In a first aspect, the present invention provides a method for controlling energy storage charging and discharging, comprising:

[0009] Obtaining the historical demand for grid inlet and outlet lines in a preset time period, the historical demand for energy storage inlet and outlet lines in a preset time period, and the charging and discharging time period of the energy storage system;

[0010] Obtaining a user historical load demand curve of the energy storage system according to the historical demand of the grid inlet and outlet lines and the historical demand of the energy storage inlet and outlet lines in the preset time period;

[0011] Predicting the maximum demand of the user for the current month based on the user's historical load demand curve of the energy storage system;

[0012] According to the maximum demand of the month and the real-time active power of the grid inlet and outlet lines in each charging and discharging time period, the charging power or discharging power of the energy storage system in the charging and discharging time period is adjusted.

[0013] Furthermore, the user historical load demand curve of the energy storage system is obtained according to the historical demand of the grid inlet and outlet lines and the historical demand of the energy storage inlet and outlet lines in the preset time period. The specific expression is:

[0014] ,

[0015] in, For the The historical load demand of users in a time unit, For the The historical demand of the grid inlet and outlet lines for each time unit, For the The preset time period includes multiple time units, and the user historical load demand curve of the energy storage system is composed of the connection lines of the user historical load demands of multiple time units.

[0016] Furthermore, the predicting of the user's maximum demand for the month based on the user's historical load demand curve of the energy storage system includes:

[0017] When the maximum demand of the user in the current month is predicted to be the maximum demand of the user on the first day of the current month, the maximum demand of the valley section of the working day of the previous month, the minimum demand of the valley section of the previous month, and the average demand of the peak section of the previous month are obtained according to the historical load demand curve of the user of the energy storage system;

[0018] Determine the average peak load absorption capacity and absorption capacity of the user's grid connection point based on the regional peak duration and the average peak demand of the previous month;

[0019] Obtain the monthly production plan change load and energy storage additional load of the plant area, and combine the maximum demand of the valley section on the working day of the previous month, the minimum demand of the valley section on the working day of the previous month, the average absorption capacity and absorption capacity of the peak load of the user's grid connection point to obtain the maximum predicted value of the user's demand for the current month and the minimum predicted value of the user's demand for the current month;

[0020] The maximum demand of the user in that month is obtained according to the maximum predicted value of the user's demand in that month and the minimum predicted value of the user's demand in that month.

[0021] Furthermore, the specific expression for determining the average peak load absorption capacity and absorption capacity of the user's grid connection point based on the regional peak duration and the average peak demand of the previous month is:

[0022] ,

[0023] ,

[0024] in, is the average peak load absorption capacity of the user's grid connection point, is the average demand during the peak period of the previous month, is the duration of the regional peak period, is the margin coefficient, generally 95%, The absorption capacity of the user's grid connection point, The energy storage capacity of the energy storage system at the user's grid connection point.

[0025] Furthermore, the monthly production plan change load and energy storage additional load of the plant area are obtained, and the maximum demand of the valley section of the working day of the previous month, the minimum demand of the valley section of the working day of the previous month, and the average absorption capacity and absorption capacity of the peak load of the user's grid connection point are combined to obtain the maximum predicted value of the user's demand for the current month and the minimum predicted value of the user's demand for the current month. The specific expression is:

[0026] ,

[0027] ,

[0028] in, is the maximum predicted value of the user's demand for the month, is the minimum forecast value of the user's demand for the month, is the average peak load absorption capacity of the user's grid connection point, The maximum demand during the valley period on working days last month, The minimum demand during the valley period on working days last month. The energy storage capacity of the energy storage system at the user's grid connection point, is the duration of the regional valley period, is the load trend coefficient for the same period in previous years, is the monthly production plan change load of the factory area, Add load to the energy storage.

[0029] Furthermore, the maximum demand of the user in the month is obtained according to the maximum predicted value of the user's demand in the month and the minimum predicted value of the user's demand in the month. The specific expression is:

[0030] ,

[0031] in, The maximum demand of the user in that month, is the first proportionality coefficient.

[0032] Furthermore, the energy storage charging and discharging control method further includes:

[0033] If the user's maximum demand for the month is greater than the allowable transmission capacity of the incoming cable at the user's grid connection point, the allowable transmission capacity of the incoming cable at the user's grid connection point shall be used as the user's maximum demand for the month.

[0034] Furthermore, the predicting of the user's maximum demand for the month based on the user's historical load demand curve of the energy storage system also includes:

[0035] When the predicted maximum demand of the user for the month is the maximum demand of the user on a day other than the first day of the month, based on the user's historical load curve of the energy storage system, when the energy storage system capacity is discharged on the previous day, the maximum demand of the user for the month is determined based on the SOC value at the end of the valley segment on the previous day; when the energy storage system capacity is not discharged on the previous day, the maximum demand of the user for the month is determined based on the SOC value at the end of the peak segment on the previous day.

[0036] Furthermore, the charging power or discharging power of the energy storage system in each charging and discharging time period is adjusted according to the maximum demand of the month and the real-time active power of the grid inlet and outlet lines in each charging and discharging time period, specifically:

[0037] In the charging stage, the difference between the maximum demand of the month and the real-time active power of the grid inlet and outlet lines during the time period is compared with the maximum charging power to obtain the charging power adjustment or the discharging power adjustment of the energy storage system;

[0038] During the discharge phase, the difference between the real-time active power of the grid inlet and outlet lines and the lower limit of the load power during this period is compared with the maximum discharge power to obtain the discharge power adjustment of the energy storage system.

[0039] Furthermore, during the charging phase, the difference between the maximum demand of the month and the real-time active power of the grid inlet and outlet lines during the time period is compared with the maximum charging power to obtain a charging power adjustment or a discharging power adjustment of the energy storage system, including:

[0040] like , the charging power of the energy storage system is adjusted to ;

[0041] like , the charging power of the energy storage system is adjusted to ;

[0042] like , the discharge power of the energy storage system is adjusted to 0;

[0043] in, is the maximum demand of the month during the charging phase, is the real-time active power of the grid inlet and outlet lines during this period, is the maximum charging power;

[0044] In the discharge phase, the difference between the real-time active power of the grid inlet and outlet lines and the load power lower limit in the time period is compared with the maximum discharge power to obtain the discharge power adjustment amount of the energy storage system, including:

[0045] like , the discharge power of the energy storage system is adjusted to ;

[0046] like , the discharge power of the energy storage system is adjusted to ;

[0047] like , the discharge power of the energy storage system is adjusted to 0;

[0048] in, is the lower limit of load power, is the real-time active power of the grid inlet and outlet lines during this period, is the maximum discharge power.

[0049] In a second aspect, the present invention further provides an energy storage charging and discharging control device, comprising:

[0050] A data acquisition module, used to acquire the historical demand of the power grid inlet and outlet lines in a preset time period, the historical demand of the energy storage inlet and outlet lines in a preset time period, and the charging and discharging time period of the energy storage system;

[0051] A historical load demand calculation module, used to obtain a user historical load demand curve of the energy storage system according to the historical demand of the power grid inlet and outlet lines and the historical demand of the energy storage inlet and outlet lines in the preset time period;

[0052] A maximum demand determination module, used to predict the user's maximum demand for the month based on the user's historical load demand curve of the energy storage system;

[0053] The charging and discharging power adjustment module is used to adjust the charging power or discharging power of the energy storage system in each charging and discharging time period according to the maximum demand of the month and the real-time active power of the grid inlet and outlet lines in each charging and discharging time period.

[0054] In a third aspect, the present invention further provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of any one of the energy storage charge and discharge control methods in the first aspect.

[0055] In a fourth aspect, the present invention further provides a computer device, comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, it executes any one of the energy storage charging and discharging control methods in the first aspect.

[0056] The beneficial effects of adopting the above technical solution are as follows: the present invention ensures that the maximum demand value of the user is controlled within a reasonable range during the charging and discharging process of the energy storage system, the charging and discharging power is less than the maximum charging and discharging power, and prevents the occurrence of power reverse transmission by comparing the incoming power of the power grid, the maximum demand prediction value, and the maximum charging and discharging power of the energy storage system; and adjusts the charging and discharging strategy of the energy storage control system in combination with the time-of-use electricity price and the predicted user demand, fully considering the factors of user demand and energy storage system load on the basis of minimizing the user's electricity cost, so that the electric energy stored in the energy storage system is used with the highest efficiency, and can avoid the occurrence of power reverse transmission due to excessive or too low total user load, which is of positive significance to the safe and economical operation of the user's energy storage system. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0058] Figure 1 This is a schematic diagram of an energy storage charging and discharging control method in one embodiment of the present application;

[0059] Figure 2 This is a schematic diagram of the grid-connected energy storage system architecture in one embodiment of the present application;

[0060] Figure 3 This is a schematic diagram of a prior art energy storage plan curve in one embodiment of the present application;

[0061] Figure 4 This is a schematic representation of the peak and valley time-of-use electricity price of the power grid system in one embodiment of the present application;

[0062] Figure 5 This is a schematic diagram of a user load power curve during a non-peak period of a certain day in an embodiment of the present application;

[0063] Figure 6 This is a schematic diagram of a power curve of a power grid after superimposing the power of an energy storage system in an embodiment of the present application;

[0064] Figure 7 A schematic diagram of the charging and discharging power of an energy storage system in one embodiment of the present application;

[0065] Figure 8 This is a schematic diagram of the overall situation of the power curves of the power grid and the inlet and outlet lines of each load in one embodiment of the present application;

[0066] Fig. 9 This is a schematic diagram of an energy storage charging and discharging control device in one embodiment of the present application. DETAILED DESCRIPTION

[0067] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. In order to explain the present invention in more detail, the energy storage charging and discharging control method, device, storage medium and equipment provided by the present invention are specifically described below in combination with the drawings.

[0068] Unless otherwise defined, the technical terms or scientific terms used in the disclosure of this application should be understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, similar words such as "one", "one" or "the" do not indicate a quantitative limit, but indicate that there is at least one. Similar words such as "include" or "include" mean that the elements or objects appearing in front of the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Similar words such as "connect" or "connected" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship can also change accordingly.

[0069] The current two-part electricity price includes electricity charges, basic electricity charges, and power factor adjustment charges. The basic electricity charges can be calculated according to the transformer capacity or the maximum demand. If the basic electricity charge is calculated according to the maximum demand, the billing capacity is the maximum demand recorded by the maximum demand meter installed by the power supply department, and the maximum demand can only increase continuously; for example, 15 minutes is used as a time unit, and the power consumption in the first 15-minute time period is taken as the maximum demand. If the power consumption in the next time period is greater than the current maximum demand, the maximum demand is updated with the power consumption in the next time period. If the power consumption in the next time period is less than the current maximum demand, the maximum demand is not updated. The above maximum demand is limited by the total capacity of the transformer. The maximum demand is lower than a certain proportion of the total capacity of the transformer, or lower than a certain proportion of the total capacity of the transformer and the high-voltage motor that does not pass through the transformer, which is equivalent to the lower limit of the load power. The maximum demand is obtained by the sum of the capacities at the preset ratio. In this case, there is a large gap between the actual electricity load and the contracted electricity load. Regardless of whether the actual electricity load is too high or too low, the user's electricity cost will increase accordingly.

[0070] Combined with Figure 3As shown in the energy storage plan curve, for user-side energy storage, it is usually discharged during the peak electricity price period and charged during the valley electricity price period, and the electricity price cost of user energy storage is balanced through the peak-valley price difference. Taking the two-part electricity price of industrial and commercial electricity in a certain province as an example, the charging and discharging strategy is to charge (a total of 8 hours) between 00:00-08:00 (i.e. the first valley period), discharge (a total of 2 hours) between 10:00-12:00 (i.e. the first peak period), charge (a total of 2 hours) between 12:00-14:00 (i.e. the second valley period), and discharge (a total of 2 hours) between 15:00-17:00 (i.e. the second peak period) (a total of 2 hours) (in the peak electricity price period from July to September) or discharge (a total of 5 hours) between 14:00-19:00 (i.e. the second peak period) (in the non-peak electricity price period in other months). According to the peak and valley period setting, if the energy storage system is configured as a 0.5C system, that is, it can be fully charged or fully discharged once in 2 hours, there are two peak electricity price periods throughout the day, and two charges and two discharges can be completed every day. Taking other months without peak electricity prices as an example, the energy storage plan curve trend is roughly as shown in the attached figure. Figure 3 shown.

[0071] in , Charging the energy storage system, , Discharge the energy storage system. The price difference between charging and discharging twice a day can be obtained through the energy storage curve:

[0072] ,

[0073] .

[0074] In addition to arbitrage through peak-valley price differences, the energy storage system will also increase the user's load during the peak electricity price period, and reduce the load during the valley electricity price period. It may happen that the maximum demand value in the short period of time during the peak electricity price period is much higher than the maximum demand value in other time periods, or the load in the valley electricity price period is lower than the load power lower limit. Due to the charging and discharging of energy storage at the corresponding time, the maximum demand in the peak electricity price period is reduced and the load in the valley electricity price period is increased. According to the above analysis, the basic electricity bill of users who implement the two-part electricity price is also reduced accordingly.

[0075] In order to improve the utilization efficiency of the energy storage system, the energy storage system should be fully discharged during the peak electricity price period and fully charged during the valley electricity price period as much as possible. However, due to the instability of user load, if the user load is too low during the set discharge period of the energy storage system, the energy discharge of the energy storage system may cause the load value to be lower than the lower limit of the load power, or even power reverse transmission may occur. Similarly, if the user load is too high during the set charging period of the energy storage system, the charging of the energy storage system may cause the maximum demand value to increase abnormally, causing the energy storage system to be overloaded and the user to be unable to fully consume the electricity, resulting in unnecessary waste of electricity in the energy storage system.

[0076] In this regard, the present invention provides an energy storage charge and discharge control method. Aiming at the original energy storage system charge and discharge control logic, the maximum demand value is integrated into the energy storage system charge and discharge control strategy, so that the user's maximum demand value is controlled within a reasonable range, and the charge and discharge power is less than the maximum charge and discharge power, to prevent the occurrence of power reverse transmission. Figure 1 The schematic diagram and attached diagram of the energy storage charging and discharging control method are shown in FIG. Figure 2 The schematic diagram of the energy storage system architecture shown is used to illustrate the application of this method to a terminal device as an example.

[0077] This embodiment provides an application scenario of the energy storage charge and discharge control method, which includes the terminal device provided in the embodiment, and the terminal device includes but is not limited to a smart phone and a computer device, wherein the computer device can be at least one of a desktop computer, a portable computer, a laptop computer, a mainframe computer, a platform computer, a tablet computer, a server, a cloud server, etc. It is used to operate the terminal device to obtain the energy storage system charge and discharge control strategy. For the specific process, please refer to the embodiment of the energy storage charge and discharge control method.

[0078] It should be noted that the energy storage charging and discharging control method in this embodiment can be Figure 2 The station-level EMS system shown in the figure is executed. The station-level EMS system is a station-level energy management system (Energy Management System, EMS) of the energy storage system, which is a set of integrated software and hardware management systems for monitoring, controlling and optimizing the operation of the energy storage system. It is usually set up in an energy storage power station and is responsible for managing and scheduling energy storage resources to meet various application requirements. Its main functions include but are not limited to data acquisition, status monitoring, charge and discharge control, optimized scheduling, safety protection, fault diagnosis and alarm, remote monitoring and operation, etc.

[0079] In this embodiment, the energy storage system refers to a system that can store and release electrical energy and is composed of a single or multiple electrochemical energy storage units, including a battery system, an inverter, a step-up transformer and a collection line; a single or multiple energy storage systems constitute an energy storage grid-connected system with power collection; the electrochemical energy storage unit is composed of an electrochemical battery, a power converter connected to it, and a battery management system, and is the smallest energy storage unit that can independently store and release electrical energy.

[0080] Step S101, obtaining the historical demand of the grid inlet and outlet lines in a preset time period, the historical demand of the energy storage inlet and outlet lines in a preset time period, and the charging and discharging time period of the energy storage system.

[0081] Specifically, during the application process, the historical demand of the power grid inlet and outlet and the historical demand of the energy storage inlet and outlet can be derived from the power grid operation platform. The historical demand of the power grid inlet and outlet and the historical demand of the energy storage inlet and outlet can be measured in minutes as the time unit of data measurement. The preset time period can be the day before the day of energy storage charge and discharge control, the week before the week, or the month before the month. Different time lengths can be set according to the actual credibility requirements of the historical demand. It should be noted that in this embodiment, the power of the power grid inlet and outlet is in the direction of flowing into the bus as the positive direction, and the power of the energy storage inlet and outlet is in the direction of flowing out of the bus as the positive direction.

[0082] Combined with Figure 4 It should be noted that the charging and discharging time period of the energy storage system is consistent with the peak and valley time period of the power grid system. The energy storage system discharges during the peak period, that is, the peak period of the power grid system is the discharge period of the energy storage system. Figure 4 10:00-12:00 and 14:-19:00 are the discharging time periods of the energy storage system; the energy storage system is charged during the off-peak period, that is, the off-peak period of the power grid system is the charging time period of the energy storage system. Figure 4 00:00-10:00, 12:00-14:00, and 19:00-24:00 are the charging time periods for the energy storage system.

[0083] Step S102, obtaining a user historical load demand curve of the energy storage system according to the historical demand of the grid inlet and outlet lines and the historical demand of the energy storage inlet and outlet lines in the preset time period.

[0084] The user historical load demand curve of the energy storage system is obtained according to the historical demand of the grid inlet and outlet lines and the historical demand of the energy storage inlet and outlet lines in the preset time period. The specific expression is:

[0085] ,

[0086] in, For the The historical load demand of users in a time unit, For the The historical demand of the grid inlet and outlet lines for each time unit, For the The preset time period includes multiple time units, and the user historical load demand curve of the energy storage system is composed of the connection lines of the user historical load demand of multiple time units. In this embodiment, the preset time period can be set to 1 day (24 hours), the time unit is 1 minute, and the corresponding number of time units is It is 1440.

[0087] Step S103: predicting the maximum demand of the user in the current month based on the historical load demand curve of the user of the energy storage system.

[0088] Among them, in step S103, the maximum demand of the user in the current month is predicted according to the historical load demand curve of the user of the energy storage system. According to the predicted maximum demand of the user in the current month being the maximum demand on the first day of the current month or the maximum demand on a day other than the first day of the current month, combined with the specific historical load demand curve, there are two maximum demand prediction methods:

[0089] (1) When the maximum demand of the user in the month is predicted to be the maximum demand on the first day of the month

[0090] Step S201, when the user's maximum demand for the month is predicted to be the user's maximum demand on the first day of the month, the maximum demand for the valley section of the working day of the previous month, the minimum demand for the valley section of the previous month, and the average demand for the peak section of the previous month are obtained according to the user's historical load demand curve of the energy storage system.

[0091] Step S202, determining the average peak load absorption capacity and absorption capability of the user's grid connection point according to the regional peak duration and the average peak demand of the previous month.

[0092] Specifically, in the above step S202, the expression for determining the average peak load absorption capacity and absorption capacity of the user's grid connection point according to the regional peak duration and the average peak demand of the previous month is:

[0093] ,

[0094] ,

[0095] in, is the average peak load absorption capacity of the user's grid connection point, is the average demand during the peak period of the previous month, is the duration of the regional peak period, is the margin coefficient, which is determined based on the stability of the grid-connected load and is generally 95%. The absorption capacity of the user's grid connection point, The energy storage capacity of the energy storage system at the user's grid connection point.

[0096] Step S203, obtain the monthly production plan change load and energy storage additional load of the plant, and combine the maximum demand in the valley section of the working day of the previous month, the minimum demand in the valley section of the working day of the previous month, the average absorption capacity and absorption capacity of the peak load of the user's grid connection point to obtain the maximum predicted value of the user's demand for the current month and the minimum predicted value of the user's demand for the current month.

[0097] Specifically, the calculation of the maximum forecast value and the minimum forecast value of the user's monthly demand is different according to the different absorption capacity of the user's grid connection point:

[0098] ,

[0099] ,

[0100] in, is the maximum predicted value of the user's demand for the month, is the minimum forecast value of the user's demand for the month, is the average peak load absorption capacity of the user's grid connection point, The maximum demand during the valley period on working days last month, The minimum demand during the valley period on working days last month. The energy storage capacity of the energy storage system at the user's grid connection point, is the duration of the regional valley period, is the load trend coefficient for the same period in previous years, is the monthly production plan change load of the factory area, Add load to the energy storage.

[0101] Step S204, obtaining the user's maximum demand for the month according to the user's maximum predicted demand for the month and the user's minimum predicted demand for the month.

[0102] In the above step S204, the maximum demand of the user in the current month is obtained according to the maximum predicted value of the user's demand in the current month and the minimum predicted value of the user's demand in the current month. The specific expression is:

[0103] ,

[0104] in, The maximum demand of the user in that month, is the first proportionality coefficient.

[0105] In addition, the maximum demand also needs to meet the constraint condition of being less than the allowable transmission capacity of the incoming cable at the user's grid connection point. If the user's maximum demand for the month is greater than the allowable transmission capacity of the incoming cable at the user's grid connection point, the allowable transmission capacity of the incoming cable at the user's grid connection point shall be used as the user's maximum demand for the month.

[0106] The specific expression of the maximum demand satisfying the constraint condition that it is less than the allowable transmission capacity of the incoming cable at the user's grid connection point is:

[0107] ,

[0108] ,

[0109] The transmission capacity allowed by the incoming cable at the user's grid connection point, The rated voltage of the busbar of the incoming cable at the user's grid connection point. The allowable current carrying capacity of the incoming cable at the user's grid connection point.

[0110] (2) When the user's maximum demand for the month is predicted to be the maximum demand on a day other than the first day of the month

[0111] When the predicted maximum demand of the user for the month is the maximum demand of the user on a day other than the first day of the month, based on the user's historical load curve of the energy storage system, when the energy storage system capacity is discharged on the previous day, the maximum demand of the user for the month is determined based on the SOC value at the end of the valley segment on the previous day; when the energy storage system capacity is not discharged on the previous day, the maximum demand of the user for the month is determined based on the SOC value at the end of the peak segment on the previous day.

[0112] Specifically, on the premise that the energy storage system was discharged on the previous day, the maximum demand value of the previous day is adjusted according to the shortfall value of the SOC value at the end of the previous day; on the premise that the energy storage system capacity of the previous day is not discharged, the charging power of the next day's valley section is adjusted according to the SOC value at the end of the previous day's peak section.

[0113] For example, when the energy storage capacity is discharged, a shortage appears at the end of the valley period, which means it is not fully charged. The system only needs two hours to be fully charged at full speed, while there are eight hours in the valley period. If it is not fully charged, it means that the user load is too close to the predicted maximum demand at this time, and the system cannot charge to increase the load. However, the valley period itself is a time period with extremely low user load, and when it reaches the peak period, it is very likely to exceed the currently predicted maximum demand, indicating that the maximum demand forecast is too small and the maximum demand needs to be increased.

[0114] If the energy storage is not emptied, it means that the discharge rate is slow. The essence of discharge is to reduce the system load. What affects the discharge rate is the load lower limit power. However, when the generator and transformer have been determined, the discharge rate is fixed, so the discharge rate cannot be changed. The only way is to reduce the charging power so that the charging and discharging of the battery are basically offset within a day, reducing the loss caused by battery charging and discharging.

[0115] Furthermore, after the predicted maximum demand of the energy storage system for the current month is determined in the power grid system, a policy needs to be issued, including global parameters and planned curve parameters. Specifically, the "parameter decentralization initiator" needs to determine the global parameters and planned curve parameters for the first day of the next month within the time period of 00:00-23:00, and manually initiate a parameter decentralization application; the parameter decentralization application is transferred to the "parameter decentralization reviewer", and the "parameter decentralization reviewer" needs to review the parameters to be decentralized before 23:00 on the same day. If there is a problem with the decentralization parameters, the application is rejected; if there is no problem with the decentralization parameters, it is transferred to the "parameter decentralization approver" for approval; the parameter decentralization application is transferred to the "parameter decentralization approver", and the "parameter decentralization approver" needs to approve the parameters to be decentralized before 23:00 on the same day. If there is a problem with the decentralization parameters, the application is rejected; if there is no problem with the decentralization parameters, the parameters to be decentralized enter the parameter message pool to be decentralized on the operation platform and are decentralized on time at 23:30 on the same day. If the approval process of the parameter issuance application is not completed before 23:00, the parameter issuance application will be invalidated and the parameters will not be issued. If the parameters cannot be issued normally, the staff will need to manually enter the control strategy parameters on the on-site equipment.

[0116] Step S104, adjusting the charging power or discharging power of the energy storage system in each charging and discharging time period according to the maximum demand of the month and the real-time active power of the grid inlet and outlet lines in each charging and discharging time period.

[0117] The above step S104 adjusts the charging power or discharging power of the energy storage system during the charging and discharging time period, which is specifically defined as follows according to the charging stage and the discharging stage:

[0118] Step S301, during the charging phase, the difference between the maximum demand of the month and the real-time active power of the grid inlet and outlet lines during the time period is compared with the maximum charging power to obtain a charging power adjustment or a discharging power adjustment of the energy storage system.

[0119] Specifically, in the charging stage, the difference between the maximum demand of the month and the real-time active power of the grid inlet and outlet lines during the time period is compared with the maximum charging power to obtain the charging power adjustment or the discharging power adjustment of the energy storage system, including:

[0120] like , the charging power of the energy storage system is adjusted to ;

[0121] like , the charging power of the energy storage system is adjusted to ;

[0122] like , the discharge power of the energy storage system is adjusted to 0;

[0123] in, is the maximum demand of the month during the charging phase, is the real-time active power of the grid inlet and outlet lines during this period, is the maximum charging power.

[0124] Step S302, in the discharge phase, compare the difference between the real-time active power of the grid inlet and outlet lines and the load power lower limit in the time period with the maximum discharge power to obtain the discharge power adjustment amount of the energy storage system.

[0125] Specifically, in the discharge phase, the difference between the real-time active power of the grid inlet and outlet lines and the load power lower limit during the time period is compared with the maximum discharge power to obtain the discharge power adjustment of the energy storage system, including:

[0126] like , the discharge power of the energy storage system is adjusted to ;

[0127] like , the discharge power of the energy storage system is adjusted to ;

[0128] like , the discharge power of the energy storage system is adjusted to 0;

[0129] in, is the lower limit of load power, is the real-time active power of the grid inlet and outlet lines during this period, is the maximum discharge power.

[0130] Combined with Figure 5 The power curve of user load during non-peak hours on a certain day is shown in Figure 1. is the lower limit of load power, power In order to consider the maximum demand value of the month with margin, in the actual energy storage charging and discharging control process, the incoming power of the grid after adding the energy storage system should be kept within the range of the two dotted lines as much as possible. Therefore, the incoming power curve of the grid after superimposing the power of the energy storage system is as shown in the attached figure. Figure 6 As shown in the attached figure, the charging and discharging power of the energy storage system is Figure 7 As shown, the power of the energy storage system inlet and outlet lines is in the positive direction of the direction flowing into the busbar, that is, , Charging the energy storage system, , The energy storage system is discharged. At this time, the overall situation of the power curves of the power grid and each load inlet and outlet is as shown in the attached figure. Figure 8 shown.

[0131] It should be understood that although the Figure 1The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Figure 1 At least part of the steps may include multiple sub-steps or sub-stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0132] The energy storage charge and discharge control method is described in detail in the embodiments disclosed in the present invention. The above method disclosed in the present invention can be implemented by various forms of equipment. Therefore, the present invention also discloses an energy storage charge and discharge control device corresponding to the above method. Fig. 9 , specific embodiments are given below to explain in detail.

[0133] The data acquisition module 401 is used to acquire the historical demand of the power grid inlet and outlet lines in a preset time period, the historical demand of the energy storage inlet and outlet lines in a preset time period, and the charging and discharging time period of the energy storage system;

[0134] A historical load demand calculation module 402 is used to obtain a user historical load demand curve of the energy storage system according to the historical demand of the power grid inlet and outlet lines and the historical demand of the energy storage inlet and outlet lines in the preset time period;

[0135] A maximum demand determination module 403 is used to predict the user's maximum demand for the month based on the user's historical load demand curve of the energy storage system;

[0136] The charging and discharging power adjustment module 404 is used to adjust the charging power or discharging power of the energy storage system in each charging and discharging time period according to the maximum demand of the month and the real-time active power of the grid inlet and outlet lines in each charging and discharging time period.

[0137] For the energy storage charging and discharging control device, all the above-mentioned methods can be referred to, and no further details will be given here. Each module in the above-mentioned device can be implemented in whole or in part by software, hardware and a combination thereof. Each of the above-mentioned modules can be embedded in or independent of the processor of the terminal device in the form of hardware, or can be stored in the memory of the terminal device in the form of software, so that the processor can call and execute the operations corresponding to each of the above modules.

[0138] In one embodiment, the present invention further provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the steps of the above-mentioned energy storage charging and discharging control method are implemented.

[0139] The computer-readable storage medium may be an electronic memory such as a flash memory, an EEPROM (electrically erasable programmable read-only memory), an EPROM (erasable programmable read-only memory), a hard disk or a ROM. Optionally, the computer-readable storage medium includes a non-transitory computer-readable storage medium. The computer-readable storage medium has a storage space for program codes for executing any method step of the above method. These program codes may be read from or written into one or more computer program products, and the program codes may be compressed in an appropriate form.

[0140] In one embodiment, the present invention provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the above-mentioned energy storage charging and discharging control method when executing the computer program.

[0141] The computer device includes a memory, a processor, and one or more computer programs, wherein the one or more computer programs can be stored in the memory and configured to be executed by one or more processors, and the one or more application programs are configured to execute the above-mentioned energy storage charging and discharging control method.

[0142] The processor may include one or more processing cores. The processor uses various interfaces and lines to connect the various parts of the entire computer device, and executes various functions of the computer device and processes data by running or executing instructions, programs, code sets or instruction sets stored in the memory, and calling data stored in the memory. Optionally, the processor can be implemented in at least one hardware form of digital signal processing (Digital Signal Processing, DSP), field programmable gate array (Field-Programmable Gate Array, FPGA), and programmable logic array (Programmable Logic Array, PLA). The processor can integrate one or more combinations of a central processing unit (Central Processing Unit, CPU), a reporting verifier (Graphics Processing Unit, GPU) for buried data, and a modem. Among them, the CPU mainly processes the operating system, user interface, and application programs; the GPU is responsible for rendering and drawing display content; and the modem is used to process wireless communications. It can be understood that the above-mentioned modem may not be integrated into the processor, but may be implemented separately through a communication chip.

[0143] The memory may include a random access memory (RAM) or a read-only memory (ROM). The memory may be used to store instructions, programs, codes, code sets or instruction sets. The memory may include a program storage area and a data storage area, wherein the program storage area may store instructions for implementing an operating system, instructions for implementing at least one function (such as a touch function, a sound playback function, an image playback function, etc.), instructions for implementing the above-mentioned various method embodiments, etc. The data storage area may also store data created by the terminal device during use, etc.

[0144] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for controlling energy storage charging and discharging, characterized in that: include: Obtaining the historical demand for grid inlet and outlet lines in a preset time period, the historical demand for energy storage inlet and outlet lines in a preset time period, and the charging and discharging time period of the energy storage system; Obtaining a user historical load demand curve of the energy storage system according to the historical demand of the grid inlet and outlet lines and the historical demand of the energy storage inlet and outlet lines in the preset time period; Predicting the maximum demand of the user for the current month based on the user's historical load demand curve of the energy storage system; According to the maximum demand of the month and the real-time active power of the grid inlet and outlet lines in each charging and discharging time period, the charging power or discharging power of the energy storage system in the charging and discharging time period is adjusted; The predicting of the user's maximum demand for the month based on the user's historical load demand curve of the energy storage system includes: When the maximum demand of the user in the current month is predicted to be the maximum demand of the user on the first day of the current month, the maximum demand of the valley section of the working day of the previous month, the minimum demand of the valley section of the previous month, and the average demand of the peak section of the previous month are obtained according to the historical load demand curve of the user of the energy storage system; Determine the average peak load absorption capacity and absorption capacity of the user's grid connection point based on the regional peak duration and the average peak demand of the previous month; Obtain the monthly production plan change load and energy storage additional load of the plant area, and combine the maximum demand of the valley section on the working day of the previous month, the minimum demand of the valley section on the working day of the previous month, the average absorption capacity and absorption capacity of the peak load of the user's grid connection point to obtain the maximum predicted value of the user's demand for the current month and the minimum predicted value of the user's demand for the current month; The maximum demand of the user in that month is obtained according to the maximum predicted value of the user's demand in that month and the minimum predicted value of the user's demand in that month.

2. The energy storage charging and discharging control method according to claim 1, characterized in that: The user historical load demand curve of the energy storage system is obtained according to the historical demand of the grid inlet and outlet lines and the historical demand of the energy storage inlet and outlet lines in the preset time period. The specific expression is: ， in, For the The historical load demand of users in a time unit, For the The historical demand of the grid inlet and outlet lines for each time unit, For the The preset time period includes multiple time units, and the user historical load demand curve of the energy storage system is composed of the connection lines of the user historical load demands of multiple time units.

3. The energy storage charging and discharging control method according to claim 1, characterized in that: The specific expression for determining the average peak load absorption capacity and absorption capacity of the user's grid connection point based on the regional peak duration and the average peak demand of the previous month is: ， ， in, is the average peak load absorption capacity of the user's grid connection point, is the average demand during the peak period of the previous month, is the duration of the regional peak period, is the margin coefficient, generally 95%, The absorption capacity of the user's grid connection point, The energy storage capacity of the energy storage system at the user's grid connection point.

4. The energy storage charging and discharging control method according to claim 3, characterized in that: The monthly production plan change load and energy storage additional load of the plant area are obtained, and the maximum demand of the valley section of the working day of the previous month, the minimum demand of the valley section of the working day of the previous month, and the average absorption capacity and absorption capacity of the peak load of the user's grid connection point are combined to obtain the maximum predicted value of the user's demand for the current month and the minimum predicted value of the user's demand for the current month. The specific expression is: ， ， in, is the maximum predicted value of the user's demand for the month, is the minimum forecast value of the user's demand for the month, is the average peak load absorption capacity of the user's grid connection point, The maximum demand during the valley period on working days last month, The minimum demand during the valley period on working days last month. The energy storage capacity of the energy storage system at the user's grid connection point, is the duration of the regional valley period, is the load trend coefficient for the same period in previous years, is the monthly production plan change load of the factory area, Add load to the energy storage.

5. The energy storage charging and discharging control method according to claim 4, characterized in that: The maximum demand of the user in the month is obtained according to the maximum predicted value of the user's demand in the month and the minimum predicted value of the user's demand in the month. The specific expression is: ， in, The maximum demand of the user in that month, is the first proportionality coefficient.

6. The energy storage charging and discharging control method according to claim 5, characterized in that: Also includes: If the user's maximum demand for the month is greater than the allowable transmission capacity of the incoming cable at the user's grid connection point, the allowable transmission capacity of the incoming cable at the user's grid connection point shall be used as the user's maximum demand for the month.

7. The energy storage charging and discharging control method according to claim 1, characterized in that: The predicting of the user's maximum demand for the month based on the user's historical load demand curve of the energy storage system also includes: When the predicted maximum demand of the user for the month is the maximum demand of the user on a day other than the first day of the month, based on the user's historical load curve of the energy storage system, when the energy storage system capacity is discharged on the previous day, the maximum demand of the user for the month is determined based on the SOC value at the end of the valley segment on the previous day; when the energy storage system capacity is not discharged on the previous day, the maximum demand of the user for the month is determined based on the SOC value at the end of the peak segment on the previous day.

8. The energy storage charging and discharging control method according to claim 1, characterized in that: The charging power or discharging power of the energy storage system in each charging and discharging time period is adjusted according to the maximum demand of the month and the real-time active power of the grid inlet and outlet lines in each charging and discharging time period, specifically: In the charging stage, the difference between the maximum demand of the month and the real-time active power of the grid inlet and outlet lines during the time period is compared with the maximum charging power to obtain the charging power adjustment or the discharging power adjustment of the energy storage system; During the discharge phase, the difference between the real-time active power of the grid inlet and outlet lines and the lower limit of the load power during this period is compared with the maximum discharge power to obtain the discharge power adjustment of the energy storage system.

9. The energy storage charging and discharging control method according to claim 8, characterized in that: In the charging stage, the difference between the maximum demand of the month and the real-time active power of the grid inlet and outlet lines during the time period is compared with the maximum charging power to obtain the charging power adjustment amount or the discharging power adjustment amount of the energy storage system, including: like , the charging power of the energy storage system is adjusted to ; like , the charging power of the energy storage system is adjusted to ; like , the discharge power of the energy storage system is adjusted to 0; in, is the maximum demand of the month during the charging phase, is the real-time active power of the grid inlet and outlet lines during this period, is the maximum charging power; In the discharge phase, the difference between the real-time active power of the grid inlet and outlet lines and the load power lower limit in the time period is compared with the maximum discharge power to obtain the discharge power adjustment amount of the energy storage system, including: like , the discharge power of the energy storage system is adjusted to ; like , the discharge power of the energy storage system is adjusted to ; like , the discharge power of the energy storage system is adjusted to 0; in, is the lower limit of load power, is the real-time active power of the grid inlet and outlet lines during this period, is the maximum discharge power.

10. An energy storage charging and discharging control device, characterized in that: include: A data acquisition module, used to acquire the historical demand of the grid inlet and outlet lines in a preset time period, the historical demand of the energy storage inlet and outlet lines in a preset time period, and the charging and discharging time period of the energy storage system; A historical load demand calculation module, used to obtain a user historical load demand curve of the energy storage system according to the historical demand of the power grid inlet and outlet lines and the historical demand of the energy storage inlet and outlet lines in the preset time period; A maximum demand determination module, used to predict the user's maximum demand for the month based on the user's historical load demand curve of the energy storage system; A charging and discharging power adjustment module, used to adjust the charging power or discharging power of the energy storage system in each charging and discharging time period according to the maximum demand of the month and the real-time active power of the grid inlet and outlet lines in each charging and discharging time period; The predicting of the user's maximum demand for the month based on the user's historical load demand curve of the energy storage system includes: When the maximum demand of the user in the current month is predicted to be the maximum demand of the user on the first day of the current month, the maximum demand of the valley section of the working day of the previous month, the minimum demand of the valley section of the previous month, and the average demand of the peak section of the previous month are obtained according to the historical load demand curve of the user of the energy storage system; Determine the average peak load absorption capacity and absorption capacity of the user's grid connection point based on the regional peak duration and the average peak demand of the previous month; Obtain the monthly production plan change load and energy storage additional load of the plant area, and combine the maximum demand of the valley section on the working day of the previous month, the minimum demand of the valley section on the working day of the previous month, the average absorption capacity and absorption capacity of the peak load of the user's grid connection point to obtain the maximum predicted value of the user's demand for the current month and the minimum predicted value of the user's demand for the current month; The maximum demand of the user in that month is obtained according to the maximum predicted value of the user's demand in that month and the minimum predicted value of the user's demand in that month.

11. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of any one of the energy storage charging and discharging control methods of claims 1-9 are implemented.

12. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, it executes any one of the energy storage charging and discharging control methods of claims 1-9.

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