Energy storage system charging method and charging system

Abstract

The application discloses a kind of energy storage system charging method and charging system.The energy storage system charging method includes: if the photovoltaic charging module and the alternating current charging module are accessed charging, the alternating current charging power of the alternating current charging module is adjusted until the difference between the alternating current charging power and battery maximum charging power is first preset value;The photovoltaic charging power of the photovoltaic charging module is started at the first preset value;Determine whether the battery charging power reaches the battery maximum charging power;If the battery charging power reaches the battery maximum charging power, the alternating current charging power is controlled to reduce the second preset value, and the photovoltaic charging power is controlled to increase the second preset value.By using the above scheme, the problem of slow overall charging and unstable charging power supplied to the battery causing safety hazards when charging simultaneously using photovoltaic charging and grid alternating current charging is solved.

Description

Technical Field

[0001] This invention relates to the technical field of energy storage systems, and more particularly to a charging method and charging system for energy storage systems. Background Technology

[0002] Current energy storage systems typically include batteries, which are usually charged using two methods: photovoltaic (PV) charging and grid AC charging. PV charging involves converting sunlight into electricity through photovoltaic panels to charge the battery. Grid AC charging involves converting the AC input from the grid into the DC power required by the battery. For residential energy storage systems, grid AC charging typically involves converting the household AC input into the DC power needed by the battery. When charging the batteries in an energy storage system, either PV charging or grid AC charging can be used alone, or both methods can be used simultaneously.

[0003] In existing solutions, when both photovoltaic (PV) charging and grid AC charging are used simultaneously, the battery charging power is the sum of the PV charging power and the grid AC charging power. To maximize the utilization of PV charging, PV charging is generally prioritized, with grid AC charging serving as an auxiliary supplement. That is, PV charging will output at its maximum PV charging power. When the maximum PV charging power does not reach the battery's maximum charging power, grid AC charging will be used as a supplement to make the sum of the PV charging power and the grid AC charging power close to the battery's maximum charging power.

[0004] However, existing photovoltaic (PV) charging priority schemes have the following drawbacks: Firstly, PV charging is slow due to the influence of sunlight conditions. Secondly, for fast charging, both PV charging power and AC charging power must be adjusted simultaneously to make the sum of PV charging power and grid AC charging power close to the battery's maximum charging power. However, the PV charging power is limited by sunlight, requiring constant adjustments to both PV and AC charging power. This results in unstable charging power supplied to the battery, potentially exceeding the battery's maximum allowable charging power and causing overcharging. Overcharging can easily lead to battery fires, posing a safety hazard. Summary of the Invention

[0005] This invention provides a charging method and system for an energy storage system to solve the problems of slow overall charging and unstable charging power supplied to the battery when using both photovoltaic charging and grid AC charging simultaneously, which can cause safety hazards.

[0006] According to one aspect of the present invention, a charging method for an energy storage system is provided, for use in an energy storage system charging system, the energy storage system charging system including a photovoltaic charging module and an AC charging module; the photovoltaic charging module is used for photovoltaic charging of a battery, and the AC charging module is used for AC charging of the battery; the energy storage system charging method includes: Determine whether both the photovoltaic charging module and the AC charging module are connected to the charging circuit; If both the photovoltaic charging module and the AC charging module are connected to charging, adjust the AC charging power of the AC charging module until the difference between the AC charging power and the maximum charging power of the battery is a first preset value. The photovoltaic charging power of the photovoltaic charging module is controlled to start at the first preset value; Obtain battery charging power; Determine whether the battery charging power has reached the battery's maximum charging power; If the battery charging power reaches the battery's maximum charging power, control the AC charging power to decrease by the second preset value and control the photovoltaic charging power to increase by the second preset value, and execute the step of determining whether the battery charging power has reached the battery's maximum charging power.

[0007] In an optional embodiment of the present invention, the first preset value and the second preset value are equal in size.

[0008] In an optional embodiment of the present invention, at least one of the first preset value and the second preset value is greater than 15W and less than 30W.

[0009] In an optional embodiment of the present invention, at least one of the first preset value and the second preset value is 20W.

[0010] In an optional embodiment of the present invention, after controlling the AC charging power to decrease by the second preset value and controlling the photovoltaic charging power to increase by the second preset value, the method further includes: Determine whether the difference between the battery charging power and the battery's maximum charging power is greater than the second preset value; If the difference between the battery charging power and the battery maximum charging power is greater than the second preset value, the AC charging power is controlled to increase by the second preset value, and the step of determining whether the difference between the battery charging power and the battery maximum charging power is greater than the second preset value is executed.

[0011] In an optional embodiment of the present invention, before adjusting the AC charging power of the AC charging module until the difference between the AC charging power and the maximum charging power of the battery is a first preset value, the method further includes: Determine the connection order of the photovoltaic charging module and the AC charging module; Accordingly, adjusting the AC charging power of the AC charging module until the difference between the AC charging power and the battery's maximum charging power is a first preset value includes: The AC charging power of the AC charging module is adjusted based on the access order of the photovoltaic charging module and the AC charging module until the difference between the AC charging power and the maximum charging power of the battery is a first preset value.

[0012] In an optional embodiment of the present invention, adjusting the AC charging power of the AC charging module based on the access order of the photovoltaic charging module and the AC charging module until the difference between the AC charging power and the maximum charging power of the battery is a first preset value includes: When the photovoltaic charging module is connected first and then the AC charging module is connected, the photovoltaic charging module is controlled to stop charging, and the AC charging power of the AC charging module is controlled to increase stepwise at the second preset value until the difference between the AC charging power and the maximum charging power of the battery is the first preset value. When the AC charging module is connected first and then the photovoltaic charging module is connected, the AC charging power of the AC charging module is controlled to be reduced to a first preset value, which is the difference between the AC charging power of the AC charging module and the maximum charging power of the battery.

[0013] According to another aspect of the present invention, a charging system for an energy storage system is provided for charging an energy storage system, the energy storage system including a battery, and the charging system for the energy storage system including a monitoring module, a motherboard module, a photovoltaic charging module and an AC charging module; The photovoltaic charging module is electrically connected to the first power supply terminal of the battery and is used for photovoltaic charging of the battery. The AC charging module is electrically connected to the second power supply terminal of the battery and is used to convert AC power into DC power to charge the battery. The input terminal of the monitoring module is electrically connected to the battery, and the monitoring module is used to monitor the charging power of the battery. The motherboard module is communicatively connected to the monitoring module, the photovoltaic charging module, and the AC charging module. The motherboard module is used to execute the energy storage system charging method described above.

[0014] In an optional embodiment of the present invention, the motherboard module is used to obtain the maximum charging power of the battery through the monitoring module when the photovoltaic charging module is charging alone, and to control the photovoltaic charging module to charge the battery based on the maximum charging power of the battery; The motherboard module is used to obtain the maximum charging power of the battery through the monitoring module when the AC charging module is charging alone, and to control the AC charging module to charge the battery based on the maximum charging power of the battery.

[0015] In an optional embodiment of the present invention, the motherboard module communicates with at least one of the monitoring module, the photovoltaic charging module, and the AC charging module via a UART communication interface.

[0016] The technical solution of this invention, when both the photovoltaic charging module and the AC charging module are connected for charging, first adjusts the AC charging power of the AC charging module until the difference between the AC charging power and the maximum charging power of the battery is a first preset value. Then, it controls the photovoltaic charging power of the photovoltaic charging module to start at the first preset value. That is, AC charging is prioritized when starting, and photovoltaic charging is started only when the difference between the AC charging power and the maximum battery power is small. This fully utilizes the stability of AC power supply and fine-tunes the unstable photovoltaic charging on the basis of stable AC charging to achieve a stable battery charging power. At this point, the battery charging power is acquired and it is determined whether the battery charging power has reached the battery's maximum charging power. When the battery's maximum charging power is reached, the AC charging power is reduced by a second preset value, and the photovoltaic charging power is increased by the second preset value. Since the battery charging power is the sum of the AC charging power and the photovoltaic charging power, the battery charging power will reach the battery's maximum charging power after photovoltaic charging starts. At this point, reducing the AC charging power and increasing the photovoltaic charging power can fully utilize green energy solar photovoltaic charging. When there is strong sunlight, the photovoltaic charging power also increases, which can keep the battery charging power at a value close to the battery's maximum charging power, thus enabling fast charging. It also makes full use of the stability of grid AC charging, and even if photovoltaic charging is affected by sunlight conditions, it can still provide a stable charging power to the battery. This solves the problem of slow overall charging and unstable charging power supplied to the battery when using both photovoltaic charging and grid AC charging simultaneously, which can cause safety hazards.

[0017] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a flowchart of a charging method for an energy storage system provided in Embodiment 1 of the present invention; Figure 2This is a flowchart of a charging method for an energy storage system provided in Embodiment 2 of the present invention; Figure 3 This is a flowchart of a charging method for an energy storage system provided in Embodiment 2 of the present invention; Figure 4 This is a schematic diagram of the structure of an energy storage system charging system provided in Embodiment 4 of the present invention.

[0020] Among them: 61, motherboard module; 62, AC charging module; 63, photovoltaic charging module; 64, monitoring module; 65, battery. Detailed Implementation

[0021] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0022] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0023] Example 1 Figure 1 This is a flowchart of a charging method for an energy storage system provided in Embodiment 1 of the present invention. This embodiment is applicable to charging the battery of an energy storage system. The method is used in an energy storage system charging system, which includes a photovoltaic charging module and an AC charging module. The photovoltaic charging module is used for photovoltaic charging of the battery, and can convert the DC power provided by the photovoltaic panel into the DC power required by the battery to charge it. The AC charging module is used for AC charging of the battery, and can convert household AC input power into the DC power required by the battery to charge it. The energy storage system charging method includes: S110. Determine whether both the photovoltaic charging module and the AC charging module are connected to the charging circuit.

[0024] Whether or not charging is connected refers to whether the module is electrically connected to the battery to charge it. In practical applications, it is possible to connect only the photovoltaic charging module to charge the battery, or only the AC charging module to charge the battery, or both the photovoltaic and AC charging modules may be used simultaneously. By determining whether both the photovoltaic and AC charging modules are connected, it is possible to determine whether simultaneous photovoltaic and AC charging of the battery is necessary.

[0025] If both the photovoltaic charging module and the AC charging module are connected to charging, proceed to step S120; if one of the photovoltaic charging module and the AC charging module is not connected to charging, proceed to step S110.

[0026] S120. Adjust the AC charging power of the AC charging module until the difference between the AC charging power and the maximum charging power of the battery is a first preset value.

[0027] Here, AC charging power refers to the charging power provided by the AC charging module for AC charging the battery, the maximum charging power of the battery refers to the maximum charging power required by the battery, and the first preset value refers to a preset power value. By making the difference between the AC charging power and the maximum charging power of the battery equal to the first preset value, the AC charging power can be made close to the maximum charging power of the battery.

[0028] S130. Control the photovoltaic charging power of the photovoltaic charging module to start at the first preset value.

[0029] The photovoltaic charging power starting at the first preset value means that the initial power value of the photovoltaic charging module when it starts charging is the first preset value.

[0030] S140, Obtain battery charging power.

[0031] Among them, battery charging power refers to the power supplied to the battery by the current photovoltaic charging module and AC charging module. When both the photovoltaic charging module and the AC charging module output power to charge the battery, the battery charging power is the sum of the AC charging power and the photovoltaic charging power.

[0032] S150. Determine whether the battery charging power has reached the battery's maximum charging power.

[0033] If the battery charging power reaches the battery's maximum charging power, proceed to step S160, and then proceed to step S150 to determine whether the battery charging power has reached the battery's maximum charging power. If the battery charging power has not reached the battery's maximum charging power, continue to proceed to step S150 to continuously determine whether the battery charging power has reached the battery's maximum charging power.

[0034] S160, Control the AC charging power to decrease the second preset value and control the photovoltaic charging power to increase the second preset value.

[0035] Specifically, controlling the AC charging power to decrease by the second preset value means reducing the AC charging power by the second preset value from its current level, while controlling the photovoltaic charging power to increase by the second preset value means increasing the photovoltaic charging power by the second preset value from its current level. When the battery charging power reaches the battery's maximum charging power, it indicates that the battery has reached the maximum charging power required. At this point, controlling the AC charging power to decrease by the second preset value and controlling the photovoltaic charging power to increase by the second preset value can adjust the power ratio of AC charging and photovoltaic charging, increasing the photovoltaic charging power and reusing green energy solar photovoltaic charging. Furthermore, if the battery charging power reaches the battery's maximum charging power again after adjustment, the AC charging power will again decrease by the second preset value and the photovoltaic charging power will again increase by the second preset value. Therefore, the stability of AC charging can be fully utilized, and the unstable photovoltaic charging can be fine-tuned on the basis of stable AC charging to achieve a stable battery charging power. Simultaneously, the battery charging power will be maintained at a value close to the battery's maximum charging power, thus enabling rapid charging.

[0036] The above solution, when both the photovoltaic charging module and the AC charging module are connected for charging, first adjusts the AC charging power of the AC charging module until the difference between the AC charging power and the maximum charging power of the battery is a first preset value. Then, it controls the photovoltaic charging power of the photovoltaic charging module to start at the first preset value. That is, AC charging is prioritized at startup, and photovoltaic charging is started when the difference between the AC charging power and the maximum battery power is small. This fully utilizes the stability of AC power supply and fine-tunes the unstable photovoltaic charging on the basis of stable AC charging to achieve a stable battery charging power. At this point, the battery charging power is acquired and it is determined whether the battery charging power has reached the battery's maximum charging power. When the battery's maximum charging power is reached, the AC charging power is reduced by a second preset value, and the photovoltaic charging power is increased by the second preset value. Since the battery charging power is the sum of the AC charging power and the photovoltaic charging power, the battery charging power will reach the battery's maximum charging power after photovoltaic charging starts. At this point, reducing the AC charging power and increasing the photovoltaic charging power can fully utilize green energy solar photovoltaic charging. When there is strong sunlight, the photovoltaic charging power also increases, which can keep the battery charging power at a value close to the battery's maximum charging power, thus enabling fast charging. It also makes full use of the stability of grid AC charging, and even if photovoltaic charging is affected by sunlight conditions, it can still provide a stable charging power to the battery. This solves the problem of slow overall charging and unstable charging power supplied to the battery when using both photovoltaic charging and grid AC charging simultaneously, which can cause safety hazards.

[0037] In an optional embodiment of the present invention, the first preset value and the second preset value are equal in size.

[0038] Specifically, by making the first preset value and the second preset value equal, the photovoltaic charging power of the photovoltaic charging module can reach the maximum charging power of the battery as soon as possible when it starts with the first preset value. This allows for effective fine-tuning of the AC charging power and the photovoltaic charging power, so that the battery charging power is maintained at a value that is the difference between the battery charging power and the maximum charging power of the battery and the first preset value.

[0039] In an optional embodiment of the present invention, at least one of the first preset value and the second preset value is greater than 15W and less than 30W.

[0040] If the first preset value and the second preset value are too large, the battery charging power will rise too quickly, which may lead to overcharging. If the first preset value and the second preset value are too small, the battery charging power will take too long to reach the maximum charging power, resulting in slow charging speed. By taking at least one of the first preset value and the second preset value within the range of greater than 15W and less than 30W, the battery charging speed can be improved while effectively preventing overcharging.

[0041] Based on the above embodiments, at least one of the first preset value and the second preset value is 20W.

[0042] By setting at least one of the first preset value and the second preset value to 20W, it is possible to prevent battery overcharging and enable the battery charging power to rise to the battery's maximum charging power as quickly as possible, resulting in faster battery charging speed. This effectively prevents battery overcharging while increasing battery charging speed.

[0043] Example 2 Figure 2 This is a flowchart of a charging method for an energy storage system provided in Embodiment 2 of the present invention. This embodiment is an improvement upon Embodiment 1, and optionally, after controlling the AC charging power to decrease by the second preset value and controlling the photovoltaic charging power to increase by the second preset value, it further includes: determining whether the difference between the battery charging power and the battery's maximum charging power is greater than the second preset value; if the difference between the battery charging power and the battery's maximum charging power is greater than the second preset value, controlling the AC charging power to increase by the second preset value, and executing the step of determining whether the difference between the battery charging power and the battery's maximum charging power is greater than the second preset value. Based on this, as... Figure 2 As shown, the charging method for this energy storage system includes: S210. Determine whether both the photovoltaic charging module and the AC charging module are connected to the charging circuit.

[0044] If both the photovoltaic charging module and the AC charging module are connected to charging, proceed to step S120; if one of the photovoltaic charging module and the AC charging module is not connected to charging, proceed to step S110.

[0045] S220. Adjust the AC charging power of the AC charging module until the difference between the AC charging power and the maximum charging power of the battery is a first preset value.

[0046] S230. Control the photovoltaic charging power of the photovoltaic charging module to start at the first preset value.

[0047] S240, Obtain battery charging power.

[0048] S250. Determine whether the battery charging power has reached the battery's maximum charging power.

[0049] If the battery charging power reaches the battery's maximum charging power, proceed to step S260, and then proceed to step S250 to determine whether the battery charging power has reached the battery's maximum charging power. If the battery charging power has not reached the battery's maximum charging power, continue to proceed to step S250 to continuously determine whether the battery charging power has reached the battery's maximum charging power.

[0050] S260, Control the AC charging power to decrease the second preset value and control the photovoltaic charging power to increase the second preset value.

[0051] S270. Determine whether the difference between the battery charging power and the battery maximum charging power is greater than the second preset value.

[0052] If the difference between the battery charging power and the battery's maximum charging power is greater than the second preset value, proceed to step S280. After S280, proceed to step S270 to determine whether the difference between the battery charging power and the battery's maximum charging power is greater than the second preset value. If the difference between the battery charging power and the battery's maximum charging power is not greater than the second preset value, continue to proceed to step S270.

[0053] S280, Control the AC charging power to increase the second preset value.

[0054] Wherein, when the difference between the battery charging power and the battery's maximum charging power is greater than the second preset value, it indicates that the light intensity is weak and the photovoltaic charging power is insufficient. Therefore, at this time, the AC charging power is controlled to increase the second preset value. Increasing the AC charging power can keep the battery power within the range where the difference between the battery charging power and the battery's maximum charging power is not greater than the second preset value. 3. It makes full use of the stability of the AC grid, so that even if the photovoltaic is affected by the light conditions, it can still provide stable charging power to the battery.

[0055] Example 3 Figure 3 This is a flowchart of a charging method for an energy storage system provided in Embodiment 3 of the present invention. This embodiment is an improvement upon Embodiment 1, and optionally, before adjusting the AC charging power of the AC charging module until the difference between the AC charging power and the maximum charging power of the battery is a first preset value, it further includes: determining the connection order of the photovoltaic charging module and the AC charging module; correspondingly, adjusting the AC charging power of the AC charging module until the difference between the AC charging power and the maximum charging power of the battery is a first preset value includes: adjusting the AC charging power of the AC charging module based on the connection order of the photovoltaic charging module and the AC charging module until the difference between the AC charging power and the maximum charging power of the battery is a first preset value. Based on this, as... Figure 3 As shown, the charging method for this energy storage system includes: S310. Determine whether both the photovoltaic charging module and the AC charging module are connected to the charging circuit.

[0056] If both the photovoltaic charging module and the AC charging module are connected to charging, proceed to step S120; if one of the photovoltaic charging module and the AC charging module is not connected to charging, proceed to step S110.

[0057] S320. Determine the connection order of the photovoltaic charging module and the AC charging module.

[0058] The connection sequence refers to the order in which the photovoltaic charging module and the AC charging module are connected to the battery to charge it.

[0059] S330. Adjust the AC charging power of the AC charging module based on the access order of the photovoltaic charging module and the AC charging module until the difference between the AC charging power and the maximum charging power of the battery is a first preset value.

[0060] When the photovoltaic (PV) charging module is connected first, since the AC charging module is not connected at that time, the PV charging module will initially supply power to the battery independently. In this case, the PV charging module has PV charging power output, while the AC charging module's AC output power is 0. Conversely, when the AC charging module is connected first, since the PV charging module is not connected at that time, the AC charging module will initially supply power to the battery independently, and the PV charging module will not output power, resulting in 0 PV charging power. Therefore, the AC charging power differs depending on the connection order. Thus, adjusting the AC charging power of the AC charging module until the difference between the AC charging power and the battery's maximum charging power equals a first preset value is necessary. This requires adjusting the AC charging power of the AC charging module based on the connection order of the PV charging module and the AC charging module.

[0061] For example, adjusting the AC charging power of the AC charging module based on the access order of the photovoltaic charging module and the AC charging module until the difference between the AC charging power and the maximum charging power of the battery is a first preset value includes: When the photovoltaic charging module is connected first and then the AC charging module is connected, the photovoltaic charging module is controlled to stop charging, and the AC charging power of the AC charging module is controlled to increase stepwise according to the second preset value until the difference between the AC charging power and the maximum charging power of the battery is the first preset value.

[0062] When the AC charging module is connected first and then the photovoltaic charging module is connected, the AC charging power of the AC charging module is controlled to be reduced to a first preset value, which is the difference between the AC charging power of the AC charging module and the maximum charging power of the battery.

[0063] When the photovoltaic charging module is connected first and then the AC charging module is connected, the photovoltaic charging module will initially supply power to the battery independently, while the AC charging module will have zero AC output power. Therefore, the photovoltaic charging module needs to be stopped first, and then the AC charging power of the AC charging module needs to be increased incrementally in steps according to the second preset value until the difference between the AC charging power and the battery's maximum charging power reaches the first preset value. This incremental approach prevents the AC charging power from suddenly increasing beyond the battery's charging power and ensures that the AC charging module is activated and stabilized until the difference between the AC charging power and the battery's maximum charging power reaches the first preset value.

[0064] When the AC charging module is connected first and then the photovoltaic charging module is connected, the photovoltaic charging module is not connected at this time. Therefore, the AC charging module will output power to the battery separately first, and the photovoltaic charging module will not output. The photovoltaic charging power is 0, so there is no need to turn off the output of the photovoltaic charging module. Since the AC charging module is relatively stable, it can meet the maximum charging power of the battery when outputting alone. Therefore, at this time, the AC charging power of the AC charging module is directly reduced to the difference between the AC charging power of the AC charging module and the maximum charging power of the battery, which is the first preset value.

[0065] S340. Control the photovoltaic charging power of the photovoltaic charging module to start at the first preset value.

[0066] S350, obtain battery charging power.

[0067] S360. Determine whether the battery charging power has reached the battery's maximum charging power.

[0068] If the battery charging power reaches the battery's maximum charging power, proceed to step S370, and then proceed to step S360 to determine whether the battery charging power has reached the battery's maximum charging power. If the battery charging power has not reached the battery's maximum charging power, continue to proceed to step S360 to continuously determine whether the battery charging power has reached the battery's maximum charging power.

[0069] S370, Control the AC charging power to decrease the second preset value and control the photovoltaic charging power to increase the second preset value.

[0070] S380. Determine whether the difference between the battery charging power and the battery maximum charging power is greater than the second preset value.

[0071] If the difference between the battery charging power and the battery's maximum charging power is greater than the second preset value, proceed to step S390. After S390, proceed to step S380 to determine whether the difference between the battery charging power and the battery's maximum charging power is greater than the second preset value. If the difference between the battery charging power and the battery's maximum charging power is not greater than the second preset value, continue to proceed to step S380.

[0072] S390, Control the AC charging power to increase the second preset value.

[0073] The above solution adjusts the AC charging power of the AC charging module according to the connection order of the photovoltaic charging module and the AC charging module until the difference between the AC charging power and the maximum charging power of the battery is a first preset value. This allows for more precise utilization of the stability of AC charging under different conditions. Based on the stability of AC charging, it fine-tunes the unstable photovoltaic charging to achieve a stable battery charging power. At the same time, the battery charging power will be maintained at a value that is almost the same as the maximum charging power of the battery, thus enabling fast charging.

[0074] Example 4 Figure 4 This is a schematic diagram of the structure of a charging system for an energy storage system provided in Embodiment 4 of the present invention. Figure 4 As shown, the energy storage system charging system is used to charge the energy storage system. The energy storage system includes a battery 65, and the energy storage system charging system includes a monitoring module 64, a main board module 61, a photovoltaic charging module 63, and an AC charging module 62.

[0075] The photovoltaic charging module 63 is electrically connected to the first power supply terminal of the battery 65 for photovoltaic charging of the battery 65.

[0076] The AC charging module 62 is electrically connected to the second power supply terminal of the battery 65 and is used to convert AC power into DC power to charge the battery 65 AC power.

[0077] The input terminal of the monitoring module 64 is electrically connected to the battery 65, and the monitoring module 64 is used to monitor the charging power of the battery 65.

[0078] The motherboard module 61 is communicatively connected to the monitoring module 64, the photovoltaic charging module 63, and the AC charging module 62. The motherboard module 61 is used to execute the energy storage system charging method of any embodiment of the present invention.

[0079] The photovoltaic charging module 63 converts the DC power supplied by the photovoltaic panel into DC power needed by the battery 65 to charge it. The AC charging module 62 converts household AC input power into DC power needed by the battery 65 to charge it. The monitoring module 64 monitors the battery charging power; optionally, the monitoring module 64 can calculate the current power required by the battery 65 and perform battery monitoring functions. The motherboard module 61 is used for logic control. The motherboard module 61 can be a microprocessor, such as a microcontroller.

[0080] The above solution, when both the photovoltaic charging module 63 and the AC charging module 62 are connected for charging, the main board module 61 adjusts the AC charging power of the AC charging module 62 until the difference between the AC charging power and the maximum charging power of the battery is a first preset value. Then, it controls the photovoltaic charging power of the photovoltaic charging module 63 to start at the first preset value. That is, AC charging is prioritized when starting, and photovoltaic charging is started when the difference between the AC charging power and the maximum power of the battery 65 is small. This fully utilizes the stability of AC power supply and makes fine adjustments to the unstable photovoltaic charging on the basis of stable AC charging to achieve a stable battery charging power. At this point, the monitoring module 64 acquires the battery charging power and determines whether it has reached the battery's maximum charging power. When the maximum charging power is reached, the AC charging power is reduced by a second preset value, while the photovoltaic charging power is increased by the same preset value. Since the battery charging power is the sum of the AC charging power and the photovoltaic charging power, the battery charging power will reach its maximum after photovoltaic charging starts. Reducing the AC charging power and increasing the photovoltaic charging power at this point fully utilizes green energy solar photovoltaic charging. When sunlight is strong, the photovoltaic charging power also increases, ensuring the battery charging power remains close to the maximum charging power, thus enabling rapid charging. Furthermore, it fully utilizes the stability of grid AC charging, providing stable charging power to battery 65 even when photovoltaic charging is affected by sunlight conditions. This solves the problems of slow overall charging and unstable charging power supply to battery 65 when using both photovoltaic and grid AC charging simultaneously, which could cause safety hazards.

[0081] In an optional embodiment of the present invention, the motherboard module 61 is used to obtain the maximum charging power of the battery through the monitoring module 64 when the photovoltaic charging module 63 is charging alone, and to control the photovoltaic charging module 63 to charge the battery 65 based on the maximum charging power of the battery.

[0082] Among them, photovoltaic charging module 63 charging alone means that only photovoltaic charging module 63 is connected to charge battery 65. At this time, the photovoltaic charging module 63 is controlled to charge battery 65 based on the battery's maximum charging power, which can make the charging speed faster when only photovoltaic charging module 63 is performing photovoltaic charging.

[0083] In an optional embodiment of the present invention, the motherboard module 61 is used to obtain the maximum charging power of the battery through the monitoring module 64 when the AC charging module 62 is charging alone, and to control the AC charging module 62 to charge the battery 65 based on the maximum charging power of the battery.

[0084] Among them, AC charging module 62 charging alone means that only AC charging module 62 is connected to charge battery 65. At this time, the AC charging module 62 is controlled to charge battery 65 based on the battery's maximum charging power, which can make the charging speed faster when only AC charging module 62 is performing AC charging alone.

[0085] In an optional embodiment of the present invention, the motherboard module 61 communicates with at least one of the monitoring module 64, the photovoltaic charging module 63, and the AC charging module 62 via a UART communication interface.

[0086] UART stands for Universal Asynchronous Receiver / Receiver. It enables bidirectional communication, achieving full-duplex transmission and reception. In embedded design, UART is used for communication between the host and auxiliary devices. Therefore, the motherboard module 61 communicates with at least one of the monitoring module 64, photovoltaic charging module 63, and AC charging module 62 via the UART communication interface, facilitating data exchange with these modules.

[0087] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0088] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A charging method for an energy storage system, used in an energy storage system charging system, the energy storage system charging system comprising a photovoltaic charging module and an AC charging module; the photovoltaic charging module is used for photovoltaic charging of a battery, and the AC charging module is used for AC charging of the battery; characterized in that, The energy storage system charging method includes: Determine whether both the photovoltaic charging module and the AC charging module are connected to the charging circuit; If both the photovoltaic charging module and the AC charging module are connected to charging, adjust the AC charging power of the AC charging module until the difference between the AC charging power and the maximum charging power of the battery is a first preset value. The photovoltaic charging power of the photovoltaic charging module is controlled to start at the first preset value; Obtain battery charging power; Determine whether the battery charging power has reached the battery's maximum charging power; If the battery charging power reaches the battery's maximum charging power, control the AC charging power to decrease by a second preset value and control the photovoltaic charging power to increase by the second preset value, and execute the step of determining whether the battery charging power has reached the battery's maximum charging power; After controlling the AC charging power to decrease by the second preset value and controlling the photovoltaic charging power to increase by the second preset value, the method further includes: Determine whether the difference between the battery charging power and the battery's maximum charging power is greater than the second preset value; If the difference between the battery charging power and the battery maximum charging power is greater than the second preset value, the AC charging power is controlled to increase by the second preset value, and the step of determining whether the difference between the battery charging power and the battery maximum charging power is greater than the second preset value is executed.

2. The energy storage system charging method according to claim 1, characterized in that, The first preset value and the second preset value are equal in size.

3. The energy storage system charging method according to claim 1, characterized in that, At least one of the first preset value and the second preset value is greater than 15W and less than 30W.

4. The energy storage system charging method according to claim 3, characterized in that, At least one of the first preset value and the second preset value is 20W.

5. The charging method for an energy storage system according to any one of claims 1 to 4, characterized in that, Before adjusting the AC charging power of the AC charging module until the difference between the AC charging power and the battery's maximum charging power reaches a first preset value, the method further includes: Determine the connection order of the photovoltaic charging module and the AC charging module; Accordingly, adjusting the AC charging power of the AC charging module until the difference between the AC charging power and the battery's maximum charging power is a first preset value includes: The AC charging power of the AC charging module is adjusted based on the access order of the photovoltaic charging module and the AC charging module until the difference between the AC charging power and the maximum charging power of the battery is a first preset value.

6. The energy storage system charging method according to claim 5, characterized in that, The step of adjusting the AC charging power of the AC charging module based on the access order of the photovoltaic charging module and the AC charging module until the difference between the AC charging power and the maximum charging power of the battery is a first preset value includes: When the photovoltaic charging module is connected first and then the AC charging module is connected, the photovoltaic charging module is controlled to stop charging, and the AC charging power of the AC charging module is controlled to increase stepwise at the second preset value until the difference between the AC charging power and the maximum charging power of the battery is the first preset value. When the AC charging module is connected first and then the photovoltaic charging module is connected, the AC charging power of the AC charging module is controlled to be reduced to a first preset value, which is the difference between the AC charging power of the AC charging module and the maximum charging power of the battery.

7. A charging system for an energy storage system, controlled by the energy storage system charging method as described in any one of claims 1-6, for charging the energy storage system, wherein the energy storage system includes a battery, characterized in that, The energy storage system charging system includes a monitoring module, a motherboard module, a photovoltaic charging module, and an AC charging module; The photovoltaic charging module is electrically connected to the first power supply terminal of the battery and is used for photovoltaic charging of the battery. The AC charging module is electrically connected to the second power supply terminal of the battery and is used to convert AC power into DC power to charge the battery. The input terminal of the monitoring module is electrically connected to the battery, and the monitoring module is used to monitor the charging power of the battery; The motherboard module is communicatively connected to the monitoring module, the photovoltaic charging module, and the AC charging module. The motherboard module is used to execute the energy storage system charging method according to any one of claims 1-6.

8. The energy storage system charging system according to claim 7, characterized in that, The motherboard module is used to obtain the maximum charging power of the battery through the monitoring module when the photovoltaic charging module is charging alone, and to control the photovoltaic charging module to charge the battery based on the maximum charging power of the battery. The motherboard module is used to obtain the maximum charging power of the battery through the monitoring module when the AC charging module is charging alone, and to control the AC charging module to charge the battery based on the maximum charging power of the battery.

9. The energy storage system charging system according to claim 7 or 8, characterized in that, The motherboard module communicates with at least one of the monitoring module, the photovoltaic charging module, and the AC charging module via a UART communication interface.

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