Charging and discharging control method and device, computer device and storage device

Abstract

The invention belongs to the technical field of charging and discharging control, and particularly relates to a charging and discharging control method and device of an energy storage system, a computer device and a storage device. If the current current is greater than the first current threshold value, acquiring the current allowable maximum charging current of the battery, and judging whether the current allowable maximum charging current is greater than the minimum charging current or not; if yes, the battery is controlled to be charged with the minimum charging current; if not, the battery is controlled to be charged with the currently allowed maximum charging current; if the current current is smaller than the second current threshold value, the current allowable maximum discharge current of the battery is obtained, and whether the current allowable maximum discharge current is larger than the minimum discharge current or not is judged; if yes, controlling the battery to discharge at the minimum discharge current; and if not, controlling the battery to discharge at the current allowable maximum discharge current. The charging and discharging control method can effectively reduce the loss of the energy storage system, improve the system efficiency and further improve the income of a user.

Description

Technical Field

[0001] The present invention belongs to the technical field of charge and discharge control, and in particular relates to a charge and discharge control method, device, computer device and storage device for an energy storage system. Background Art

[0002] As the problems of global environmental pollution and climate warming become increasingly serious, people are paying more and more attention to the development of green energy. The use of green energy such as solar energy, wind energy, and hydropower can not only reduce greenhouse gas emissions, but also reduce energy use costs. However, solar energy, wind energy, and hydropower are not always available, and they are volatile and intermittent, which has become a problem for stable energy supply. The application of energy storage technology just makes up for this defect, which provides a good space for the development and application of the energy storage industry. With the guidance of national policies and the support of local governments, the energy storage industry has grown rapidly and explosively, and market competition has become increasingly fierce. People have higher and higher requirements for the safety, efficiency, and cost of energy storage systems.

[0003] At present, the mainstream energy storage system in the industry is mainly electrochemical energy storage, which usually includes energy storage batteries, PCS energy storage converter equipment (Power Conversion System), fire protection system, access control system, EMS system, BMS system and temperature control system. Energy storage batteries are carriers of electric energy storage, which are charged by the mains power of the power grid and provide the stored electric energy to the load equipment. PCS energy storage converter equipment is a battery charge and discharge control module that controls the charge and discharge current of the battery. The fire protection system is used to detect unexpected accidents such as fire and explosion. When a fire or explosion occurs, it can quickly extinguish the fire to prevent the spread of the situation and avoid disasters. The access control system is used to control whether the door of the energy storage cabinet or energy storage container is open, and to notify the door opening alarm to prevent accidents caused by non-professionals or unauthorized personnel from opening and closing the door at will. The EMS system is an energy management system used for the scheduling and management of the entire energy storage system, such as when to charge and when to discharge. The BMS system is a battery management system used to detect the voltage, current, temperature, SOC calculation, SOH calculation of the battery, as well as various battery overvoltage, overcurrent, and overtemperature protection functions. The temperature control system, also known as the heat dissipation system, is used to control the temperature of the battery. The battery cannot be charged below 0 degrees. The allowed charging and discharging currents at different temperatures are also different. Therefore, the heat dissipation system can be used to cool the battery when the temperature is high to prevent thermal runaway and damage to the battery. The battery can be heated when the temperature is low to facilitate charging.

[0004] Existing energy storage systems usually charge batteries during off-peak electricity prices and discharge batteries during peak and peak electricity prices, thereby reducing electricity costs. For example, charging a battery for 100 degrees during off-peak electricity prices costs 31 yuan; during peak electricity prices, 100 degrees of electricity are provided to load equipment. Considering the system efficiency factor, if the electricity that can be provided is 90 degrees, then the cost saved for users is 90*1.116-100*0.31=69.44 yuan. If the system efficiency is higher and the electricity that can be provided is 92 degrees, then the cost saved for users is 92*1.116-100*0.31=71.672 yuan. It can be seen that the higher the system efficiency, the greater the user benefit.

[0005] At present, the specifications adopted by energy storage systems are generally 0.5C charging / 0.5C discharging, that is, if the battery capacity is 280Ah, then the charging current 0.5C is 140A, and the discharging current 0.5C is also 140A, which means 2 hours charging / 2 hours discharging. Specifically, the system monitors the time, and when it finds that the time reaches the valley electricity price, it fully charges the battery according to the preset 2 hours. When it finds that the time reaches the peak electricity price or the peak electricity price, it allows the battery to discharge the load equipment according to the preset 2 hours. During the charging and discharging process, the greater the charging current and the greater the discharging current, the more heat is generated, and the more heat needs to be cooled by the temperature control system. The greater the power of the temperature control system, or the longer the temperature control system runs, the greater the power and the longer the temperature control system runs, the greater the loss of the entire energy storage system, the lower the system efficiency, and the less the user's benefits. Summary of the invention

[0006] Based on this, the purpose of the present invention is to provide a charge and discharge control method, device, computer device and storage device for an energy storage system, so as to fundamentally solve the problems of large loss, low system efficiency and low user benefits of the existing energy storage system during the charge and discharge process.

[0007] The embodiment of the present invention is implemented by providing a charge and discharge control method for an energy storage system, wherein the energy storage system includes a battery, and the charge and discharge control method includes: Obtain the peak electricity price period, peak electricity price period and valley electricity price period of the area where the energy storage system is located; Calculating a minimum discharge current according to the peak electricity price period, the peak electricity price period and the capacity of the battery, and calculating a minimum charge current according to the valley electricity price period and the capacity of the battery; Obtaining the current of the battery; If the current is greater than a first current threshold, controlling the battery to enter a charging mode includes: Obtaining a current maximum allowable charging current of the battery, and determining whether the current maximum allowable charging current is greater than the minimum charging current; If so, controlling the battery to charge with the minimum charging current; If not, controlling the battery to be charged with the currently allowed maximum charging current; If the current current is less than the second current threshold, controlling the battery to enter a discharge mode includes: Obtaining a current maximum allowable discharge current of the battery, and determining whether the current maximum allowable discharge current is greater than the minimum discharge current; If so, controlling the battery to discharge at the minimum discharge current; If not, the battery is controlled to discharge at the currently allowed maximum discharge current.

[0008] In some embodiments, controlling the battery to be charged with the minimum charging current includes: Determining whether the current current is greater than the minimum charging current; If so, determining whether the battery needs to enter a fast charging mode, and if it is determined that the battery does not need to enter a fast charging mode, controlling the battery to charge with the minimum charging current; If not, the battery is controlled to be charged with the minimum charging current.

[0009] In certain embodiments, if it is determined that the battery needs to enter the fast charging mode, it is determined whether the temperature control system is started. If it is determined that the temperature control system is started, the current current is lowered until the temperature control system stops, and then the battery is controlled to charge with the current current. If it is determined that the temperature control system is not started, the current current is increased until the temperature control system is started, and then the current current is lowered to control the battery to charge with the current current.

[0010] In certain embodiments, controlling the battery to discharge at the minimum discharge current comprises: Determining whether the current current is greater than the minimum discharge current; If yes, determining whether the battery needs to enter the fast-release mode, and if it is determined that the battery does not need to enter the fast-release mode, controlling the battery to discharge at the minimum discharge current; If not, the battery is controlled to discharge at the minimum discharge current.

[0011] In some embodiments, if it is determined that the battery needs to enter the fast-release mode, it is determined whether the temperature control system is started. If it is determined that the temperature control system is started, the current current is lowered until the temperature control system is stopped, and then the battery is controlled to discharge with the current current. If it is determined that the temperature control system is not started, the current current is increased until the temperature control system is started, and then the current current is lowered to control the battery to discharge with the current current.

[0012] In some embodiments, the calculating the minimum discharge current according to the peak electricity price period, the peak electricity price period and the capacity of the battery includes: Calculating the peak electricity price duration of the day according to the peak electricity price period, calculating the peak electricity price duration of the day according to the peak electricity price period, and calculating the peak peak electricity price duration of the day according to the peak electricity price period and the peak electricity price period; Obtaining the maximum value of the peak electricity price duration of the day, the peak electricity price duration of the day, and the peak peak electricity price duration of the day; According to the formula: I min放 =C / T1, the minimum discharge current is calculated, where I min放 is the minimum discharge current, C is the capacity of the battery, and T1 is the maximum value of the peak electricity price duration of the day, the peak electricity price duration of the day, and the peak peak electricity price duration of the day.

[0013] In some embodiments, the calculating the minimum charging current according to the valley electricity price period and the capacity of the battery includes: Calculate the duration of the low-valley electricity price for the day according to the low-valley electricity price period; According to the formula: I min充 =C / T2, the minimum charging current is calculated, where I min充 is the minimum charging current, C is the capacity of the battery, and T2 is the duration of the low-peak electricity price on that day.

[0014] Another embodiment of the present invention further provides a charge and discharge control device for an energy storage system, wherein the energy storage system includes a battery, and the charge and discharge control device includes: A time period acquisition unit, used to acquire a peak electricity price period, a peak electricity price period, and a valley electricity price period in the area where the energy storage system is located; a current calculation unit, configured to calculate a minimum discharge current according to the peak electricity price period, the peak electricity price period and the capacity of the battery, and to calculate a minimum charge current according to the valley electricity price period and the capacity of the battery; A current acquisition unit, used to acquire the current current of the battery; A charging mode control unit, configured to control the battery to enter a charging mode if the current current is greater than a first current threshold, the charging mode control unit comprising: A first current judgment module, used for obtaining the current maximum allowable charging current of the battery, and judging whether the current maximum allowable charging current is greater than the minimum charging current; A first charging module, configured to control the battery to be charged with the minimum charging current; A second charging module, for controlling the battery to be charged with the currently allowed maximum charging current if no; A discharge mode control unit, used to control the battery to enter a discharge mode if the current current is less than a second current threshold, the discharge mode control unit comprising: A second current judgment module, used for obtaining the current maximum allowable discharge current of the battery, and judging whether the current maximum allowable discharge current is greater than the minimum discharge current; A first discharging module, configured to control the battery to discharge at the minimum discharging current; The second discharging module is used for controlling the battery to discharge with the currently allowed maximum discharge current if no.

[0015] Another embodiment of the present invention further provides a computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the charge and discharge control method as described in any one of the embodiments of the present invention are implemented.

[0016] Another embodiment of the present invention further provides a storage device, wherein the storage device stores a computer program, and the computer program can be executed to implement the steps of the charge and discharge control method as described in any one of the embodiments of the present invention.

[0017] The charge and discharge control method provided in the embodiment of the present invention first obtains the peak electricity price period, the peak electricity price period and the valley electricity price period in the area where the energy storage system is located. Then, according to the peak electricity price period, the peak electricity price period and the capacity of the battery, the minimum discharge current is calculated, and according to the valley electricity price period and the capacity of the battery, the minimum charging current is calculated. Then the current current of the battery is obtained. If the current current is greater than the first current threshold, the battery is controlled to enter the charging mode, and entering the charging mode includes obtaining the current maximum allowable charging current of the battery, judging whether the current maximum allowable charging current is greater than the minimum charging current, if it is judged that the current maximum allowable charging current is greater than the minimum charging current, the battery is controlled to be charged with the minimum charging current, and if it is judged that the current maximum allowable charging current is not greater than the minimum charging current, the battery is controlled to be charged with the current maximum allowable charging current. If the current current is less than the second current threshold, the battery is controlled to enter the discharge mode, and entering the discharge mode includes obtaining the current maximum allowable discharge current of the battery, judging whether the current maximum allowable discharge current is greater than the minimum discharge current, and if it is judged that the current maximum allowable discharge current is greater than the minimum discharge current, the battery is controlled to discharge with the minimum discharge current, and if it is judged that the current maximum allowable discharge current is not greater than the minimum discharge current, the battery is controlled to discharge with the current maximum allowable discharge current. The charge and discharge control method calculates the minimum discharge current according to the peak electricity price period, the peak electricity price period and the capacity of the battery, and selects the current maximum allowable discharge current or the calculated minimum discharge current based on the actual situation of the battery, so as to control the battery to discharge with a smaller discharge current, and calculates the minimum charging current according to the valley electricity price period and the capacity of the battery, and selects the current maximum allowable charging current or the calculated minimum charging current based on the actual situation of the battery, so as to control the battery to charge with a smaller charging current. During the charge and discharge process, less heat is generated, and less heat needs to be cooled by the temperature control system, or even no temperature control system is required for cooling, so that the loss of the energy storage system can be effectively reduced, the system efficiency can be improved, and the user's benefits can be increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a flowchart of a charge and discharge control method provided in an embodiment of the present invention; Figure 2 It is a structural block diagram of a charge and discharge control device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0019] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Several embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0020] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0022] An embodiment of the present invention provides a charge and discharge control method for an energy storage system, wherein the energy storage system includes a battery, Figure 1 , the charge and discharge control method comprises: S100, obtaining the peak electricity price period, peak electricity price period and valley electricity price period in the area where the energy storage system is located; S200, calculating a minimum discharge current according to the peak electricity price period, the peak electricity price period and the capacity of the battery, and calculating a minimum charge current according to the valley electricity price period and the capacity of the battery; S300, obtaining the current current of the battery; S400: If the current current is greater than a first current threshold, control the battery to enter a charging mode, including: Obtaining a current maximum allowable charging current of the battery, and determining whether the current maximum allowable charging current is greater than the minimum charging current; If so, controlling the battery to charge with the minimum charging current; If not, controlling the battery to be charged with the currently allowed maximum charging current; S500: If the current current is less than a second current threshold, control the battery to enter a discharge mode, including: Obtaining a current maximum allowable discharge current of the battery, and determining whether the current maximum allowable discharge current is greater than the minimum discharge current; If so, controlling the battery to discharge at the minimum discharge current; If not, the battery is controlled to discharge at the currently allowed maximum discharge current.

[0023] In some embodiments, each region is divided into peak electricity price period, peak electricity price period, flat peak electricity price period and valley electricity price period according to the different electricity consumption conditions in each period. Refer to the following table: The above table shows the electricity price situation of a certain province at different time periods. From 0:00 to 6:00, there are 6 hours in total, and the period from January to December is the off-peak electricity price period. From 6:00 to 9:00, there are 3 hours in total, and the period from January to December is the flat-peak electricity price period. From 9:00 to 12:00, there are 3 hours in total, and the period from January to December is the peak electricity price period, and the period from February to November is the flat-peak electricity price period. From 12:00 to 16:00, there are 4 hours in total, and the period from January to December is the flat-peak electricity price period. From 16:00 to 17:00, there is 1 hour in total, and the period from January to December is the flat-peak electricity price period, and the period from February to November is the peak electricity price period. From 17:00 to 18:00, there is 1 hour in total, and the period from January to December is the peak electricity price period, and the period from February to November is the peak electricity price period. From 18:00 to 19:00, there is 1 hour in total, and the period from January to December is the peak electricity price period, and the period from February to November is the peak electricity price period. From 19:00 to 20:00, a total of 1 hour, January to December is the peak electricity price period. From 20:00 to 21:00, a total of 1 hour, January and December are the flat-peak electricity price period, July, August and September are the peak electricity price period, and the rest of the months are the peak electricity price period. From 21:00 to 22:00, a total of 1 hour, January and December are the flat-peak electricity price period, July, August and September are the peak electricity price period, and the rest of the months are the peak electricity price period. From 22:00 to 0:00, a total of 2 hours, January to December are the flat-peak electricity price period. Among them, the valley electricity price is 0.31 yuan / kWh, the flat-peak electricity price is 0.62 yuan / kWh, the peak electricity price is 0.93 yuan / kWh, and the peak electricity price is 1.116 yuan / kWh. The above are examples. There are different situations in actual provinces. The actual situation shall prevail.

[0024] In the charge and discharge control method, the peak electricity price period, peak electricity price period and valley electricity price period of the area where the energy storage system is located are first obtained. The method of obtaining can be that the user pre-configures the various electricity price periods in the area where the energy storage system is located, and the energy storage system subsequently calls and obtains them; it can also be that the energy storage system inquires and obtains the various electricity price periods corresponding to its own geographical location information from the pre-stored electricity price periods of various regions around the world / nation according to its own geographical location information; it can also be that the energy storage system inquires and obtains the various electricity price periods corresponding to its own geographical location information in a remote server through the network according to its own geographical location information. Then, according to the obtained peak electricity price period and peak electricity price period, combined with the capacity of the battery, the minimum discharge current is calculated, and according to the valley electricity price period, combined with the capacity of the battery, the minimum charging current is calculated. Among them, the battery capacity has been pre-configured when the energy storage system leaves the factory, and the energy storage system subsequently calls and obtains it. Then, the current current of the battery is obtained, and the current current is compared with the first current threshold and the second current threshold, and the first current threshold is greater than the second current threshold. If the current current is greater than the first current threshold, the battery is controlled to enter the charging mode. If the current current is less than the second current threshold, the battery is controlled to enter a discharge mode. If the current current is less than the first current threshold and greater than the second current threshold, the battery is controlled to remain in the original state.

[0025] Among them, when controlling the battery to enter the charging mode, the current maximum allowable charging current of the battery is first obtained. The current maximum allowable charging current of the battery is determined by factors such as the battery temperature and is generally preset in the battery management system. After obtaining parameters such as the battery temperature in the current state, the current maximum allowable charging current can be obtained. Then compare the current maximum allowable charging current and the minimum charging current to determine whether the current maximum allowable charging current is greater than the minimum charging current. If it is determined that the current maximum allowable charging current is greater than the minimum charging current, the battery is controlled to charge with the minimum charging current. If it is determined that the current maximum allowable charging current is not greater than the minimum charging current, the battery is controlled to charge with the current maximum allowable charging current.

[0026] Among them, when controlling the battery to enter the discharge mode, the current maximum allowable discharge current of the battery is first obtained. The current maximum allowable discharge current of the battery is determined by factors such as the battery temperature and is generally preset in the battery management system. After obtaining parameters such as the battery temperature in the current state, the current maximum allowable discharge current can be obtained. Then compare the current maximum allowable discharge current and the minimum discharge current to determine whether the current maximum allowable discharge current is greater than the minimum discharge current; if it is determined that the current maximum allowable discharge current is greater than the minimum discharge current, the battery is controlled to discharge at the minimum discharge current. If it is determined that the current maximum allowable discharge current is not greater than the minimum discharge current, the battery is controlled to discharge at the current maximum allowable discharge current.

[0027] The charge and discharge control method calculates the minimum discharge current according to the peak electricity price period, the peak electricity price period and the capacity of the battery, and selects the current maximum allowable discharge current or the calculated minimum discharge current based on the actual situation of the battery, thereby using a smaller discharge current to control the battery to discharge, and calculates the minimum charging current according to the valley electricity price period and the capacity of the battery, and selects the current maximum allowable charging current or the calculated minimum charging current based on the actual situation of the battery, thereby using a smaller charging current to control the battery to charge. During the charge and discharge process, less heat is generated, and less heat needs to be cooled by the temperature control system, or even no temperature control system is needed for cooling, thereby effectively reducing the loss of the energy storage system, improving system efficiency, and thus increasing user benefits.

[0028] In some specific embodiments of the present application, controlling the battery to charge with the minimum charging current includes: Determining whether the current current is greater than the minimum charging current; If so, determining whether the battery needs to enter a fast charging mode, and if it is determined that the battery does not need to enter a fast charging mode, controlling the battery to charge with the minimum charging current; If not, the battery is controlled to be charged with the minimum charging current.

[0029] In some embodiments, the current current and the minimum charging current are compared to determine whether the current current is greater than the minimum charging current. If it is determined that the current current is greater than the minimum charging current, then determine whether the battery needs to enter the fast charging mode to determine whether the battery is charged with higher efficiency. If it is determined that the battery does not need to enter the fast charging mode, control the battery to charge with the minimum charging current. If it is determined that the current current is not greater than the minimum charging current, it is known that charging with the minimum charging current can meet the charging demand, and then control the battery to charge with the minimum charging current.

[0030] This charge and discharge control method compares the current current with the minimum charging current to determine whether the minimum charging current meets the charging requirements. If so, charging is controlled with the minimum charging current. If not, whether it is necessary to enter the fast charging mode to determine whether the charging efficiency needs to be improved. If it is not necessary to enter the fast charging mode, charging is controlled with the minimum charging current, thereby achieving precise control of the charging process.

[0031] In some specific embodiments of the present application, if it is determined that the battery needs to enter the fast charging mode, it is determined whether the temperature control system is started. If it is determined that the temperature control system is started, the current current is lowered until the temperature control system is stopped, and then the battery is controlled to charge with the current current. If it is determined that the temperature control system is not started, the current current is increased until the temperature control system is started, and then the current current is lowered to control the battery to charge with the current current.

[0032] In some embodiments, multiple gears of current may be provided, and the current current may be adjusted according to each gear. For example, when the current current is increased or decreased, the current gear corresponding to the current current is adjusted upward or downward step by step.

[0033] If it is determined that the battery needs to enter the fast charging mode, then determine whether the temperature control system is started. If it is determined that the temperature control system is started, the current current is lowered. When the current current is low enough, the temperature control system stops. When it is determined that the temperature control system has stopped, the battery is controlled to charge with the lowered current current. If it is determined that the temperature control system is not started, the current current is increased. When the current current is high enough, the temperature control system starts. When it is determined that the temperature control system is started, the current current is lowered again, for example, the current current is adjusted down one level, and the battery is controlled to charge with the lowered current current.

[0034] After the battery enters the fast charging mode, the charge and discharge control method controls the temperature control system to stop or use the temperature control system as little as possible while controlling the current current to meet the charging demand, thereby minimizing the loss of the energy storage system, improving the system efficiency, and further maximizing the user's benefits.

[0035] In some specific embodiments of the present application, controlling the battery to discharge at the minimum discharge current includes: Determining whether the current current is greater than the minimum discharge current; If yes, determining whether the battery needs to enter the fast-release mode, and if it is determined that the battery does not need to enter the fast-release mode, controlling the battery to discharge at the minimum discharge current; If not, the battery is controlled to discharge at the minimum discharge current.

[0036] In some embodiments, the current current and the minimum discharge current are compared to determine whether the current current is greater than the minimum discharge current. If it is determined that the current current is greater than the minimum discharge current, then it is determined whether the battery needs to enter the fast-release mode to determine whether the battery is discharged with higher efficiency. If it is determined that the battery does not need to enter the fast-release mode, the battery is controlled to discharge at the minimum discharge current. If it is determined that the current current is not greater than the minimum discharge current, it is known that discharging with the minimum discharge current can meet the discharge demand, and the battery is controlled to discharge with the minimum discharge current.

[0037] The charge and discharge control method compares the current current with the minimum discharge current to determine whether the minimum discharge current meets the discharge requirement. If so, the discharge is controlled to be performed with the minimum discharge current. If not, it is further determined whether it is necessary to enter the fast-release mode to determine whether the discharge efficiency is to be improved. If it is not necessary to enter the fast-release mode, the discharge is controlled to be performed with the minimum discharge current, thereby achieving precise control of the discharge process.

[0038] In some specific embodiments of the present application, if it is determined that the battery needs to enter the fast-release mode, it is determined whether the temperature control system is started. If it is determined that the temperature control system is started, the current current is lowered until the temperature control system is stopped, and then the battery is controlled to discharge with the current current. If it is determined that the temperature control system is not started, the current current is increased until the temperature control system is started, and then the current current is lowered to control the battery to discharge with the current current.

[0039] In some embodiments, multiple gears of current may be provided, and the current current may be adjusted according to each gear. For example, when the current current is increased or decreased, the current gear corresponding to the current current is adjusted upward or downward step by step.

[0040] If it is determined that the battery needs to enter the fast-release mode, then determine whether the temperature control system is activated. If it is determined that the temperature control system is activated, the current current is lowered. When the current current is low enough, the temperature control system stops. When it is determined that the temperature control system has stopped, the battery is controlled to discharge with the lowered current current. If it is determined that the temperature control system is not activated, the current current is increased. When the current current is high enough, the temperature control system starts. When it is determined that the temperature control system is activated, the current current is lowered again, for example, the current current is adjusted down one level, and the battery is controlled to discharge with the lowered current current.

[0041] After the battery enters the fast discharge mode, the charge and discharge control method controls the temperature control system to stop or use the temperature control system as little as possible under the premise of controlling the current current to meet the discharge demand, thereby minimizing the loss of the energy storage system, improving the system efficiency, and further maximizing the user's benefits.

[0042] In some specific implementations of the present application, the calculating the minimum discharge current according to the peak electricity price period, the peak electricity price period and the capacity of the battery includes: Calculating the peak electricity price duration of the day according to the peak electricity price period, calculating the peak electricity price duration of the day according to the peak electricity price period, and calculating the peak peak electricity price duration of the day according to the peak electricity price period and the peak electricity price period; Obtaining the maximum value of the peak electricity price duration of the day, the peak electricity price duration of the day, and the peak peak electricity price duration of the day; According to the formula: I min放 =C / T1, the minimum discharge current is calculated, where I min放 is the minimum discharge current, C is the capacity of the battery, and T1 is the maximum value of the peak electricity price duration of the day, the peak electricity price duration of the day, and the peak peak electricity price duration of the day.

[0043] In some embodiments, after obtaining the peak electricity price period and the peak electricity price period, the peak electricity price duration of the day is calculated according to the peak electricity price period, the peak electricity price duration of the day is calculated according to the peak electricity price period, and the peak electricity price duration of the day and the peak electricity price duration of the day are calculated according to the peak electricity price period and the peak electricity price period, and then the peak peak electricity price duration of the day is calculated according to the sum of the peak electricity price duration of the day and the peak electricity price duration of the day. Then compare the peak electricity price duration of the day, the peak electricity price duration of the day and the peak peak electricity price duration of the day, and take the maximum value of the three. Finally, according to the formula: I min放 =C / T1, the minimum discharge current is calculated.

[0044] For example, if the battery capacity is 280Ah, the maximum value of the peak electricity price duration, the peak electricity price duration and the peak peak electricity price duration is 7 hours, then the minimum discharge current is calculated to be 40A. At this time, the battery is controlled to discharge according to the discharge current of 40A, and the battery can be discharged after 7 hours. Compared with the existing 0.5C discharge method, this embodiment uses a lower discharge current, which can reduce the heat generated during the discharge process. The less heat needs to be cooled by the temperature control system, or even no temperature control system is needed for cooling, thereby reducing the loss of the energy storage system, improving the system efficiency, and thus increasing the user's benefits.

[0045] In some specific implementations of the present application, the calculating the minimum charging current according to the valley electricity price period and the capacity of the battery includes: Calculate the duration of the low-valley electricity price for the day according to the low-valley electricity price period; According to the formula: I min充 =C / T2, the minimum charging current is calculated, where I min充is the minimum charging current, C is the capacity of the battery, and T2 is the duration of the low-peak electricity price on that day.

[0046] In some embodiments, after obtaining the valley electricity price period, the valley electricity price duration of the day is calculated according to the valley electricity price period. Finally, according to the formula: min充 =C / T2, the minimum charging current is calculated.

[0047] For example, if the battery capacity is 280Ah and the off-peak electricity price duration is 7 hours, the minimum charging current is calculated to be 40A. At this time, the battery is charged according to the 40A charging current, and the battery can be fully charged after 7 hours. Compared with the existing 0.5C charging method, this embodiment uses a lower charging current, which can reduce the heat generated during the charging process. The less heat needs to be cooled by the temperature control system, or even no temperature control system is needed for cooling, thereby reducing the loss of the energy storage system, improving the system efficiency, and thus increasing the user's benefits.

[0048] An embodiment of the present invention provides a charge and discharge control device for an energy storage system, wherein the energy storage system includes a battery, and the charge and discharge control device includes: The time period acquisition unit 100 is used to acquire the peak electricity price period, the peak electricity price period and the valley electricity price period of the area where the energy storage system is located; The current calculation unit 200 is used to calculate the minimum discharge current according to the peak electricity price period, the peak electricity price period and the capacity of the battery, and to calculate the minimum charge current according to the valley electricity price period and the capacity of the battery; A current acquisition unit 300, used to acquire the current current of the battery; The charging mode control unit 400 is used to control the battery to enter a charging mode if the current current is greater than a first current threshold. The charging mode control unit 400 includes: A first current judgment module, used for obtaining the current maximum allowable charging current of the battery, and judging whether the current maximum allowable charging current is greater than the minimum charging current; A first charging module, configured to control the battery to be charged with the minimum charging current; A second charging module, for controlling the battery to be charged with the currently allowed maximum charging current if no; The discharge mode control unit 500 is used to control the battery to enter the discharge mode if the current current is less than the second current threshold. The discharge mode control unit 500 includes: A second current judgment module, used for obtaining the current maximum allowable discharge current of the battery, and judging whether the current maximum allowable discharge current is greater than the minimum discharge current; A first discharging module, configured to control the battery to discharge at the minimum discharging current; The second discharging module is used for controlling the battery to discharge with the currently allowed maximum discharge current if no.

[0049] In some specific embodiments of the present application, the first charging module includes: A first current judgment submodule, used to judge whether the current current is greater than the minimum charging current; A first charging submodule, configured to: determine whether the battery needs to enter a fast charging mode, and if it is determined that the battery does not need to enter the fast charging mode, control the battery to be charged with the minimum charging current; The second charging submodule is used for controlling the battery to be charged with the minimum charging current if no.

[0050] In some specific embodiments of the present application, the first charging submodule is also used to determine whether the temperature control system is started if it is determined that the battery needs to enter the fast charging mode. If it is determined that the temperature control system is started, the current current is lowered until the temperature control system is stopped, and then the battery is controlled to be charged with the current current. If it is determined that the temperature control system is not started, the current current is increased until the temperature control system is started, and then the current current is lowered to control the battery to be charged with the current current.

[0051] In some specific embodiments of the present application, the first discharge module includes: A second current judgment submodule, used to judge whether the current current is greater than the minimum discharge current; A first discharge submodule, configured to determine whether the battery needs to enter a fast-discharge mode, and if it is determined that the battery does not need to enter the fast-discharge mode, control the battery to discharge at the minimum discharge current; The second discharge submodule is used for controlling the battery to discharge at the minimum discharge current if no.

[0052] In some specific embodiments of the present application, the first discharge submodule is also used to determine whether the temperature control system is started if it is determined that the battery needs to enter the fast discharge mode; if it is determined that the temperature control system is started, lower the current current until the temperature control system is stopped, and then control the battery to discharge with the current current; if it is determined that the temperature control system is not started, increase the current current until the temperature control system is started, and then lower the current current to control the battery to discharge with the current current.

[0053] In some specific implementations of the present application, the current calculation unit 200 includes: A first duration calculation module, used to calculate the peak electricity price duration of the day according to the peak electricity price period, calculate the peak electricity price duration of the day according to the peak electricity price period, and calculate the peak peak electricity price duration of the day according to the peak electricity price period and the peak electricity price period; A maximum duration acquisition module, used to acquire the maximum value of the peak electricity price duration of the day, the peak electricity price duration of the day, and the peak peak electricity price duration of the day; The first formula calculation module is used to calculate the formula: min放 =C / T1, the minimum discharge current is calculated, where I min放 is the minimum discharge current, C is the capacity of the battery, and T1 is the maximum value of the peak electricity price duration of the day, the peak electricity price duration of the day, and the peak peak electricity price duration of the day.

[0054] In some specific implementations of the present application, the current calculation unit 200 includes: A second duration calculation module is used to calculate the duration of the low-valley electricity price of the day according to the low-valley electricity price period; The second formula calculation module is used to calculate the formula: min充 =C / T2, the minimum charging current is calculated, where I min充 is the minimum charging current, C is the capacity of the battery, and T2 is the duration of the low-peak electricity price on that day.

[0055] In some embodiments, the implementation of the charge and discharge control device can refer to the implementation of the aforementioned charge and discharge control method, which will not be repeated here.

[0056] An embodiment of the present invention provides a computer device, the computer device comprising a processor, the processor being configured to implement the steps of the charge and discharge control method as described above when executing a computer program stored in a memory.

[0057] The embodiment of the present invention further provides a computer-readable storage medium on which a computer program (instructions) is stored. When the computer program (instructions) is executed by a processor, the steps of the charge and discharge control method as described above are implemented.

[0058] Exemplarily, the computer program can be divided into one or more modules, one or more modules are stored in the memory and executed by the processor to complete the present invention. One or more modules can be a series of computer program instruction segments that can complete specific functions, and the instruction segments are used to describe the execution process of the computer program in the computer device. For example, the computer program can be divided into the steps of the charge and discharge control method provided by the above-mentioned various method embodiments.

[0059] Those skilled in the art will appreciate that the above description of the computer device is merely an example and does not constitute a limitation on the computer device. The computer device may include more or fewer components than described above, or a combination of certain components, or different components, such as input and output devices, network access devices, buses, etc.

[0060] The processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc. The processor is the control center of the computer device, and uses various interfaces and lines to connect various parts of the entire computer device.

[0061] The memory can be used to store the computer program and / or module, and the processor realizes various functions of the computer device by running or executing the computer program and / or module stored in the memory, and calling the data stored in the memory. The memory can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, an application required for at least one function (such as an interface display function, an interface interaction function, etc.), etc.; the data storage area can store data created according to the use of the mobile phone (such as a map interface, a selection interface, etc.), etc. In addition, the memory can include a high-speed random access memory, and can also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0062] If the module / unit integrated in the computer device is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device that can carry the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electrical carrier signal, electrical signal and software distribution medium, etc.

[0063] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0064] The above-described embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for a person of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the attached claims.

Claims

1. A charge and discharge control method for an energy storage system, characterized in that: The energy storage system includes a battery, and the charge and discharge control method includes: Obtain the peak electricity price period, peak electricity price period and valley electricity price period of the area where the energy storage system is located; Calculating a minimum discharge current according to the peak electricity price period, the peak electricity price period and the capacity of the battery, and calculating a minimum charge current according to the valley electricity price period and the capacity of the battery; Obtaining the current of the battery; If the current current is greater than a first current threshold, controlling the battery to enter a charging mode includes: Obtaining a current maximum allowable charging current of the battery, and determining whether the current maximum allowable charging current is greater than the minimum charging current; If so, controlling the battery to charge with the minimum charging current; If not, controlling the battery to be charged with the currently allowed maximum charging current; If the current current is less than the second current threshold, controlling the battery to enter a discharge mode includes: Obtaining a current maximum allowable discharge current of the battery, and determining whether the current maximum allowable discharge current is greater than the minimum discharge current; If so, controlling the battery to discharge at the minimum discharge current; If not, the battery is controlled to discharge at the currently allowed maximum discharge current.

2. The charge and discharge control method according to claim 1, characterized in that: The controlling the battery to be charged with the minimum charging current comprises: Determining whether the current current is greater than the minimum charging current; If so, determining whether the battery needs to enter a fast charging mode, and if it is determined that the battery does not need to enter a fast charging mode, controlling the battery to charge with the minimum charging current; If not, the battery is controlled to be charged with the minimum charging current.

3. The charge and discharge control method according to claim 2, characterized in that: If it is determined that the battery needs to enter the fast charging mode, determine whether the temperature control system is started. If it is determined that the temperature control system is started, lower the current current until the temperature control system stops, and then control the battery to charge with the current current. If it is determined that the temperature control system is not started, increase the current current until the temperature control system is started, then lower the current current, and control the battery to charge with the current current.

4. The charge and discharge control method according to claim 1, characterized in that: The controlling the battery to discharge at the minimum discharge current comprises: Determining whether the current current is greater than the minimum discharge current; If yes, determining whether the battery needs to enter the fast-release mode, and if it is determined that the battery does not need to enter the fast-release mode, controlling the battery to discharge at the minimum discharge current; If not, the battery is controlled to discharge at the minimum discharge current.

5. The charge and discharge control method according to claim 4, characterized in that: If it is determined that the battery needs to enter the fast-release mode, determine whether the temperature control system is started. If it is determined that the temperature control system is started, lower the current current until the temperature control system stops, and then control the battery to discharge with the current current. If it is determined that the temperature control system is not started, increase the current current until the temperature control system is started, and then lower the current current to control the battery to discharge with the current current.

6. The charge and discharge control method according to claim 1, characterized in that: The calculating the minimum discharge current according to the peak electricity price period, the peak electricity price period and the capacity of the battery includes: Calculating the peak electricity price duration of the day according to the peak electricity price period, calculating the peak electricity price duration of the day according to the peak electricity price period, and calculating the peak peak electricity price duration of the day according to the peak electricity price period and the peak electricity price period; Obtaining the maximum value of the peak electricity price duration of the day, the peak electricity price duration of the day, and the peak peak electricity price duration of the day; According to the formula: I min放 =C / T1, the minimum discharge current is calculated, where I min放 is the minimum discharge current, C is the capacity of the battery, and T1 is the maximum value of the peak electricity price duration of the day, the peak electricity price duration of the day, and the peak peak electricity price duration of the day.

7. The charge and discharge control method according to claim 1, characterized in that: The calculating the minimum charging current according to the low-valley electricity price period and the capacity of the battery includes: Calculate the duration of the low-valley electricity price for the day according to the low-valley electricity price period; According to the formula: I min充 =C / T2, the minimum charging current is calculated, where I min充 is the minimum charging current, C is the capacity of the battery, and T2 is the duration of the low-peak electricity price on that day.

8. A charge and discharge control device for an energy storage system, characterized in that: The energy storage system includes a battery, and the charge and discharge control device includes: A time period acquisition unit, used to acquire a peak electricity price period, a peak electricity price period, and a valley electricity price period in the area where the energy storage system is located; a current calculation unit, configured to calculate a minimum discharge current according to the peak electricity price period, the peak electricity price period and the capacity of the battery, and to calculate a minimum charge current according to the valley electricity price period and the capacity of the battery; A current acquisition unit, used to acquire the current current of the battery; A charging mode control unit, configured to control the battery to enter a charging mode if the current current is greater than a first current threshold, the charging mode control unit comprising: A first current judgment module, used for obtaining the current maximum allowable charging current of the battery, and judging whether the current maximum allowable charging current is greater than the minimum charging current; A first charging module, configured to control the battery to be charged with the minimum charging current; A second charging module, for controlling the battery to be charged with the currently allowed maximum charging current if no; A discharge mode control unit, used to control the battery to enter a discharge mode if the current current is less than a second current threshold, the discharge mode control unit comprising: A second current judgment module, used for obtaining the current maximum allowable discharge current of the battery, and judging whether the current maximum allowable discharge current is greater than the minimum discharge current; A first discharging module, configured to control the battery to discharge at the minimum discharging current; The second discharging module is used for controlling the battery to discharge with the currently allowed maximum discharge current if no.

9. A computer device, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the charge and discharge control method according to any one of claims 1 to 7 when executing the computer program.

10. A storage device, characterized in that: The storage device stores a computer program, and the computer program can be executed to implement the steps of the charge and discharge control method according to any one of claims 1 to 7.

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