A photovoltaic storage system and control method and device thereof

Abstract

The present invention discloses a photovoltaic storage system and a control method and device thereof. The control method includes: obtaining the voltage value of a battery group in the photovoltaic storage system and the number of daily switching of an automatic transfer switch module in real time, and comparing the voltage value with the forbidden charging voltage of the battery group; if the voltage value is less than the forbidden charging voltage value, controlling the photovoltaic to charge the battery group, and controlling the working state of the photovoltaic storage system according to the voltage value and the number of daily switching of the automatic transfer switch module; if the voltage value is greater than or equal to the forbidden charging voltage value, controlling the battery group to supply power to the load to the recovery voltage value, and controlling the working state of the photovoltaic storage system according to the output power of the photovoltaic in the photovoltaic storage system. Under the condition that the charge state of the battery group cannot be accurately obtained, the present invention controls the working state of the photovoltaic storage system according to the voltage value of the battery group and the number of daily switching of the automatic transfer switch module, thereby increasing the service life of the photovoltaic storage system, ensuring the stability of the photovoltaic storage system, and reducing the cost.

Description

Technical Field

[0001] The present invention relates to the field of photovoltaic storage technology, and in particular to a photovoltaic storage system and a control method and device thereof. Background Art

[0002] With the rapid development of distributed new energy, the application of photovoltaic storage systems is becoming more and more extensive. The existing technology needs to rely on the charge state detected in the battery management system to control the working state of the photovoltaic storage system. The control cost is high. In addition, when the battery management system works abnormally and cannot accurately obtain the charge state of the battery pack, it is impossible to normally control the photovoltaic storage system to switch the working state. Summary of the invention

[0003] The present invention provides a photovoltaic storage system and a control method and device thereof, so as to control the working state of the photovoltaic storage system according to the voltage value of the battery pack and the number of daily switching of the automatic conversion switch module under the condition that the charge state of the battery pack cannot be accurately obtained, thereby increasing the service life of the photovoltaic storage system, ensuring the stability of the photovoltaic storage system, and reducing the cost.

[0004] According to one aspect of the present invention, a control method for a photovoltaic storage system is provided, the control method comprising:

[0005] Obtain the voltage value of the battery group in the photovoltaic storage system and the number of switching times of the automatic transfer switch module on the same day in real time, and compare the voltage value with the forbidden charging voltage value of the battery group;

[0006] If the voltage value is less than the prohibited charging voltage value, the photovoltaic power is controlled to charge the battery group, and the working state of the photovoltaic storage system is controlled according to the voltage value and the number of switching times of the automatic transfer switch module on the same day;

[0007] If the voltage value is greater than or equal to the forbidden charging voltage value, the battery group is controlled to supply power to the load to the charging recovery voltage value, and the working state of the photovoltaic storage system is controlled according to the photovoltaic output power in the photovoltaic storage system.

[0008] Furthermore, if the voltage value is less than the forbidden charging voltage value, the photovoltaic is controlled to charge the battery group, and the working state of the photovoltaic storage system is controlled according to the voltage value and the number of switching times of the automatic transfer switch module on the same day, including:

[0009] If the voltage value is less than the forbidden charging voltage value, the photovoltaic is controlled to charge the battery pack with a first preset current, and the charging voltage value of the battery pack is obtained in real time;

[0010] If the charging voltage value is greater than or equal to the preset charging voltage value and less than the prohibited charging voltage value, the working state of the photovoltaic storage system is controlled according to the voltage value and the number of switching times of the automatic transfer switch module on the same day;

[0011] If the charging voltage value is greater than or equal to the prohibited charging voltage value, the automatic transfer switch module is controlled to switch to the photovoltaic storage system to supply power to the load.

[0012] Furthermore, if the charging voltage value is greater than the preset charging voltage value and less than or equal to the forbidden charging voltage value, the working state of the photovoltaic storage system is controlled according to the voltage value and the number of daily switching of the automatic transfer switch module, including:

[0013] If the charging voltage value is greater than or equal to the preset charging voltage value and less than the forbidden charging voltage value, the photovoltaic current is limited to keep the battery pack in a static state;

[0014] The static voltage value of the battery pack is obtained, and the working state of the photovoltaic storage system is controlled according to the static voltage value and the number of switching times of the automatic transfer switch module on the same day.

[0015] Furthermore, the static voltage value of the battery pack is obtained, and the working state of the photovoltaic storage system is controlled according to the static voltage value and the number of daily switching of the automatic transfer switch module, including:

[0016] If the static voltage value is less than or equal to the preset switching voltage value or the number of switching times of the automatic transfer switch module on the same day is greater than the preset number of switching times, the photovoltaic power generation continues to be controlled to charge the battery pack with the first preset current;

[0017] If the static voltage is greater than the preset switching voltage and the number of daily switching times of the automatic transfer switch module is less than or equal to the preset switching times, the automatic transfer switch module is controlled to switch to the photovoltaic storage system for power supply.

[0018] Furthermore, if the voltage value is greater than or equal to the forbidden charging voltage value, the battery group is controlled to supply power to the load to the charging recovery voltage value, and the working state of the photovoltaic storage system is controlled according to the photovoltaic output power in the photovoltaic storage system, including:

[0019] If the voltage value is greater than or equal to the forbidden charging voltage value, the battery pack is controlled to supply power to the load to the charging recovery voltage value;

[0020] The output power of the photovoltaic power plant and the power consumption of the load are obtained, the energy state of the photovoltaic power plant is determined according to the output power of the photovoltaic power plant and the power consumption of the load, and the working state of the photovoltaic storage system is controlled according to the energy state of the photovoltaic power plant; wherein the energy state of the photovoltaic power plant includes an energy sufficient state and an energy insufficient state.

[0021] Furthermore, the working state of the photovoltaic storage system is controlled according to the photovoltaic energy state, including:

[0022] If the photovoltaic power plant is in a state of sufficient energy, the photovoltaic power plant is controlled to supply power to the load and the battery pack at the same time;

[0023] If the photovoltaic power plant is in an energy-deficient state, the photovoltaic power plant and the battery group are controlled to jointly supply power to the load.

[0024] Furthermore, the voltage value of the battery group in the photovoltaic storage system and the number of switching times of the automatic transfer switch module on the same day are obtained in real time, and the voltage value is compared with the forbidden charging voltage value of the battery group. Previously, it also includes:

[0025] It is determined whether the battery pack is in a calibrated state, and when the battery pack is in the calibrated state, the photovoltaic is controlled to charge the battery pack to a prohibited charging voltage value.

[0026] Furthermore, the voltage value of the battery group in the photovoltaic storage system and the number of switching times of the automatic transfer switch module on the same day are obtained in real time, and the voltage value is compared with the forbidden charging voltage value of the battery group. Previously, it also includes:

[0027] The number of battery cells in series, the allowable charging rate of the battery pack, and the total cell capacity in the battery pack are obtained in real time, and a preset comparison value is determined according to the number of battery cells in series, the allowable charging rate of the battery pack, and the total cell capacity in the battery pack; wherein the preset comparison value includes a forbidden charging voltage value, a long-term maximum charging current allowed for the battery pack in the equalization charging stage, and a preset switching voltage value.

[0028] According to another aspect of the present invention, a control device for a photovoltaic storage system is provided, and the control device for the photovoltaic storage system comprises:

[0029] A charging prohibition voltage comparison module is used to obtain the voltage value of the battery group in the photovoltaic storage system and the number of switching times of the automatic transfer switch module on the same day in real time, and compare the voltage value with the charging prohibition voltage value of the battery group;

[0030] The battery pack charging module is used to control the photovoltaic charging of the battery pack when the voltage value is less than the prohibited charging voltage, and control the working state of the photovoltaic storage system according to the voltage value and the number of daily switching of the automatic transfer switch module;

[0031] The load power supply module is used to control the battery group to supply power to the load to the charging recovery voltage value when the voltage value is greater than or equal to the prohibited charging voltage, and control the working state of the photovoltaic storage system according to the photovoltaic output power in the photovoltaic storage system.

[0032] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising:

[0033] at least one processor; and

[0034] a memory communicatively connected to the at least one processor; wherein,

[0035] The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the control method of the photovoltaic storage system described in any embodiment of the present invention.

[0036] According to another aspect of the present invention, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the control method of the optical storage system described in any embodiment of the present invention when executed.

[0037] According to another aspect of the present invention, there is provided a photovoltaic storage system, the photovoltaic storage system comprising:

[0038] Automatic transfer switch module, energy storage converter, DC combiner, battery pack, DC converter, multiple photovoltaic combiner boxes, multiple photovoltaic modules and control cabinet;

[0039] The first end of the automatic transfer switch module is connected to the power grid, the second end of the automatic transfer switch module is connected to the load, and the third end of the automatic transfer switch module is connected to the first end of the energy storage converter;

[0040] The second end of the energy storage converter is connected to the first end of the DC combiner cabinet, the second end of the DC combiner cabinet is connected to the first end of the DC converter, and the third end of the DC combiner cabinet is connected to the battery pack;

[0041] The first end of each photovoltaic combiner box is connected to the second end of the DC converter, and the second end of the photovoltaic combiner box is connected to a plurality of photovoltaic modules;

[0042] The control cabinet is used to obtain the voltage value of the battery group in the photovoltaic storage system and the number of switching times of the automatic transfer switch module on the same day in real time, and compare the voltage value with the forbidden charging voltage value of the battery group; if the voltage value is less than the forbidden charging voltage value, the photovoltaic is controlled to charge the battery group, and the working state of the photovoltaic storage system is controlled according to the voltage value and the number of switching times of the automatic transfer switch module on the same day; if the voltage value is greater than or equal to the forbidden charging voltage value, the battery group is controlled to supply power to the load to the charging recovery voltage value, and the working state of the photovoltaic storage system is controlled according to the output power of the photovoltaic in the photovoltaic storage system.

[0043] The control method of the photovoltaic storage system provided by the embodiment of the present invention obtains the voltage value of the battery group in the photovoltaic storage system and the number of switching times of the automatic transfer switch module on the same day in real time, compares the voltage value with the forbidden charging voltage of the battery group, controls the photovoltaic to charge the battery group when the voltage value is less than the forbidden charging voltage value, and controls the working state of the photovoltaic storage system according to the voltage value and the number of switching times of the automatic transfer switch module on the same day; when the voltage value is greater than or equal to the forbidden charging voltage value, controls the battery group to supply power to the load to the charging recovery voltage value, and controls the working state of the photovoltaic storage system according to the output power of the photovoltaic in the photovoltaic storage system. Compared with the prior art of controlling the working state of the photovoltaic storage system according to the change of the charge state of the battery group in the battery management system, the embodiment of the present invention can control the working state of the photovoltaic storage system according to the voltage value of the battery group and the number of switching times of the automatic transfer switch module on the same day when the charge state of the battery group cannot be accurately obtained. Under the condition of ensuring normal power supply to the load, the number of switching times of the automatic transfer switch module on the same day is limited, and the frequent switching of the automatic transfer switch module due to extreme weather is reduced, thereby improving the service life of the photovoltaic storage system and ensuring the stability of the photovoltaic storage system. At the same time, the photovoltaic storage system provided by the embodiment of the present invention does not need to obtain the charge state of the battery pack according to the battery management system, thereby reducing costs.

[0044] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0046] Figure 1 is a flow chart of a control method of a photovoltaic storage system provided according to an embodiment of the present invention;

[0047] Figure 2 is a flow chart of another control method of a photovoltaic storage system provided according to an embodiment of the present invention;

[0048] Figure 3 is a schematic structural diagram of a control device for a photovoltaic storage system provided according to an embodiment of the present invention;

[0049] Figure 4 A schematic diagram showing the structure of an electronic device that can be used to implement an embodiment of the present invention is shown;

[0050] Figure 5It is a structural schematic diagram of a photovoltaic storage system provided according to an embodiment of the present invention. DETAILED DESCRIPTION

[0051] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0052] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0053] The embodiment of the present invention provides a control method for a photovoltaic storage system. Figure 1 is a flow chart of a control method of a photovoltaic storage system provided according to an embodiment of the present invention, with reference to Figure 1 , control methods include:

[0054] S110, obtaining in real time the voltage value of the battery group in the photovoltaic storage system and the number of switching times of the automatic transfer switch module on the same day, and comparing the voltage value with the forbidden charging voltage value of the battery group.

[0055] Specifically, after the photovoltaic storage system is controlled to start working, the voltage value of the battery pack in the photovoltaic storage system and the number of daily switching of the automatic transfer switch module are collected in real time. Since the battery pack is in a static state at this time, the current static voltage value of the battery pack can be compared with the forbidden charging voltage value of the battery pack to determine whether the battery pack needs to be charged, wherein the forbidden charging voltage value can be understood as the voltage value at which the battery pack is forbidden to be charged. For example, in a static state, the forbidden charging voltage value of the battery pack is the product of the voltage value corresponding to a single battery cell with a state of charge of 100% and the number of battery cells connected in series in the battery pack. Among them, the battery pack includes a lead-acid battery pack.

[0056] S120: If the voltage value is less than the prohibited charging voltage value, control the photovoltaic power generation to charge the battery pack, and control the working state of the photovoltaic storage system according to the voltage value and the number of switching times of the automatic transfer switch module on the same day.

[0057] Specifically, if the voltage value is less than the forbidden charging voltage value, it means that the state of charge of the battery pack is less than 100%. At this time, it is necessary to control the photovoltaic to charge the battery pack with the first preset current, and obtain the charging voltage value of the battery pack in real time. If the charging voltage value is greater than or equal to the preset charging voltage value and less than the forbidden charging voltage value, the working state of the photovoltaic storage system is controlled according to the current voltage value of the battery pack and the number of daily switching of the automatic conversion switch module. For example, if the current voltage value of the battery pack is large and the number of daily switching of the automatic conversion switch module is small, the automatic conversion switch module can be controlled to switch to the photovoltaic storage system to supply power to the load; if the current voltage value of the battery pack is small or the number of daily switching of the automatic conversion switch module is large, the photovoltaic can be controlled to continue to supply power to the battery pack. If the photovoltaic is controlled to charge the battery pack to the forbidden charging voltage value, the automatic conversion switch module is controlled to switch to the photovoltaic storage system to supply power to the load. Among them, the first preset current and the preset charging voltage value can be set according to actual conditions, and the embodiment of the present invention does not limit this.

[0058] S130: If the voltage value is greater than or equal to the forbidden charging voltage value, the battery pack is controlled to supply power to the load to the charging recovery voltage value, and the working state of the photovoltaic storage system is controlled according to the photovoltaic output power in the photovoltaic storage system.

[0059] Specifically, if the voltage value is greater than or equal to the forbidden charging voltage, it means that the battery pack is in a fully charged state. At this time, it is necessary to control the automatic conversion switch module to switch to the battery pack to supply power to the load to the charging recovery voltage value, and determine the photovoltaic energy state according to the photovoltaic output power and the load power consumption, and control the working state of the photovoltaic storage system according to the photovoltaic energy state; wherein the photovoltaic energy state includes sufficient energy state and insufficient energy state. The control method of the photovoltaic storage system provided in the embodiment of the present invention can be applied to battery packs that do not include a battery management system, and can also be applied to battery packs with abnormal battery management systems, and the embodiment of the present invention does not limit this.

[0060] The control method of the photovoltaic storage system provided by the embodiment of the present invention obtains the voltage value of the battery group in the photovoltaic storage system and the number of switching times of the automatic transfer switch module on the same day in real time, compares the voltage value with the forbidden charging voltage of the battery group, controls the photovoltaic to charge the battery group when the voltage value is less than the forbidden charging voltage value, and controls the working state of the photovoltaic storage system according to the voltage value and the number of switching times of the automatic transfer switch module on the same day; when the voltage value is greater than or equal to the forbidden charging voltage value, controls the battery group to supply power to the load to the charging recovery voltage value, and controls the working state of the photovoltaic storage system according to the output power of the photovoltaic in the photovoltaic storage system. Compared with the prior art of controlling the working state of the photovoltaic storage system according to the change of the charge state of the battery group in the battery management system, the embodiment of the present invention can control the working state of the photovoltaic storage system according to the voltage value of the battery group and the number of switching times of the automatic transfer switch module on the same day when the charge state of the battery group cannot be accurately obtained. Under the condition of ensuring normal power supply to the load, the number of switching times of the automatic transfer switch module on the same day is limited, and the frequent switching of the automatic transfer switch module due to extreme weather is reduced, thereby improving the service life of the photovoltaic storage system and ensuring the stability of the photovoltaic storage system. At the same time, the photovoltaic storage system provided by the embodiment of the present invention does not need to obtain the charge state of the battery pack according to the battery management system, thereby reducing costs.

[0061] Furthermore, if the voltage value is less than the forbidden charging voltage value, the photovoltaic is controlled to charge the battery group, and the working state of the photovoltaic storage system is controlled according to the voltage value and the number of switching times of the automatic transfer switch module on the same day, including:

[0062] If the voltage value is less than the forbidden charging voltage value, the photovoltaic is controlled to charge the battery pack with a first preset current, and the charging voltage value of the battery pack is obtained in real time;

[0063] If the charging voltage value is greater than or equal to the preset charging voltage value and less than the prohibited charging voltage value, the working state of the photovoltaic storage system is controlled according to the voltage value and the number of switching times of the automatic transfer switch module on the same day;

[0064] If the charging voltage value is greater than or equal to the prohibited charging voltage value, the automatic transfer switch module is controlled to switch to the photovoltaic storage system to supply power to the load.

[0065] Specifically, if the voltage value is less than the forbidden charging voltage value, it means that the state of charge of the battery pack is less than 100%. At this time, the photovoltaic can be controlled to charge the battery pack with a first preset current, wherein the first preset current is the maximum charging current that the battery pack can receive, and the forbidden charging voltage value of the battery pack can be adjusted in time when the number of charging cells in the battery pack changes. By way of example, the embodiment of the present invention takes the allowable charging rate of the battery pack as C, the number of battery cells in series a=270, the allowable long-term charging and discharging rate of the battery pack as 0.1C, and the total cell capacity P in the battery pack as 600mAh as an example for explanation: Since the voltage value is less than the forbidden charging voltage value, it means that charging the battery pack at this time can make the battery pack enter the equalization charging stage. In the equalization charging stage, the long-term maximum charging current allowed by the battery pack can be determined according to the long-term charging and discharging rate allowed by the battery pack and the total cell capacity in the battery pack. By way of example, the long-term maximum charging current allowed by the battery pack in the equalization charging stage is I=0.1*P=0.1*600=60A.

[0066] In the process of charging the battery pack, the charging voltage value of the battery pack is detected in real time, and the charging voltage value of the battery pack is compared with the preset charging voltage value and the forbidden charging voltage value at the same time. If the charging voltage value is less than the preset charging voltage value, it means that the battery pack has a small amount of power. At this time, it is necessary to continue to charge the battery pack with the long-term maximum charging current allowed by the battery pack in the equalization stage; if the charging voltage value is greater than or equal to the preset charging voltage value and less than the forbidden charging voltage value, it means that the battery pack has a certain power supply capacity, and the photovoltaic current limiting treatment is required to keep the battery pack in a relatively static state, and obtain the static voltage value of the battery pack, and according to the static state The voltage value and the number of daily switching times of the automatic transfer switch module control the working state of the photovoltaic storage system. For example, if the static voltage value is less than or equal to the preset switching voltage value or the number of daily switching times of the automatic transfer switch module is greater than the preset switching number, the battery pack needs to continue to be charged with the long-term maximum charging current allowed by the battery pack in the equalization charging stage, and after the charging voltage value of the battery pack reaches the equalization charging voltage limit, the battery pack enters the floating charging stage. At this time, the charging current of the battery pack is reduced at a current decrease rate of 10% to stabilize the voltage value of the battery pack to the floating charging voltage limit of the battery pack until it reaches the forbidden charging voltage value of the battery pack. Among them, the equalization charge voltage limit can be determined according to the maximum charging voltage of a single battery cell and the number of battery cells in series. For example, the equalization charge voltage limit U1 = the maximum charging voltage of a single battery cell * the number of battery cells in series = 2.30 * a = 621V, at which time the state of charge of the battery pack is 50%; the floating charge voltage limit is the same as the equalization charge voltage limit. For example, the floating charge voltage limit U2 = the equalization charge voltage limit U1 = 2.30 * a = 621V, at which time the state of charge of the battery pack ranges from 50% to 100%. %; the forbidden charging voltage value can be determined according to the number of battery cells in series and the maximum voltage value of a single battery cell in the battery pack under different working conditions. For example, if the battery pack is in a charging state, the forbidden charging voltage value of the battery pack is the floating charge voltage limit U2 at a charging current of 0.01C; if the battery pack is in a static state, the forbidden charging voltage value of the battery pack is U3 = the static voltage value of a single battery cell in a fully charged state * the number of battery cells in series = 2.20*a = 594V, at which time the state of charge of the battery pack is 100%.

[0067] If the charging voltage value is greater than or equal to the forbidden charging voltage value, it means that the charge state of the battery pack is 100% or close to 100%, and the automatic transfer switch module can be controlled to switch to the battery pack of the photovoltaic storage system to supply power to the load.

[0068] Furthermore, if the charging voltage value is greater than or equal to the preset charging voltage value and less than the forbidden charging voltage value, the working state of the photovoltaic storage system is controlled according to the voltage value and the number of daily switching of the automatic transfer switch module, including:

[0069] If the charging voltage value is greater than or equal to the preset charging voltage value and less than the forbidden charging voltage value, the photovoltaic current is limited to keep the battery pack in a static state;

[0070] The static voltage value of the battery pack is obtained, and the working state of the photovoltaic storage system is controlled according to the static voltage value and the number of switching times of the automatic transfer switch module on the same day.

[0071] Specifically, if the charging voltage value is greater than or equal to the preset charging voltage value and less than the prohibited charging voltage value, it means that the battery pack has a certain power supply capacity at this time. At this time, the photovoltaic power generation is current limited. For example, the current limiting process can be understood as charging the battery pack for 1 minute with a charging current corresponding to a charging current rate of 0.01C to make the battery pack close to a static state. The photovoltaic power generation is current limited to determine whether the battery pack has reached the preset power supply capacity based on the charging voltage value and the static voltage value of the battery pack, thereby improving the overall utilization rate of the photovoltaic storage system. After the photovoltaic power generation is current limited, the static voltage value of the battery pack is obtained. If the static voltage value is less than or equal to the preset switching voltage value or the number of daily switching of the automatic transfer switch module is greater than the preset number of switching times, the photovoltaic power generation is continued to be controlled to charge the battery pack with the first preset current. If the static voltage is greater than the preset switching voltage value and the number of daily switching of the automatic transfer switch module is less than or equal to the preset number of switching times, the automatic transfer switch module is controlled to switch to the photovoltaic storage system for power supply. The preset charging voltage may be set according to the maximum charging voltage of a single battery cell and the number of battery cells connected in series in the battery pack. For example, the preset charging voltage U4=a*(2.3-0.05)=607.5V.

[0072] Furthermore, the static voltage value of the battery pack is obtained, and the working state of the photovoltaic storage system is controlled according to the static voltage value and the number of daily switching of the automatic transfer switch module, including:

[0073] If the static voltage value is less than or equal to the preset switching voltage value or the number of switching times of the automatic transfer switch module on the same day is greater than the preset number of switching times, the photovoltaic power generation continues to be controlled to charge the battery pack with the first preset current;

[0074] If the static voltage value is greater than the preset switching voltage value and the number of daily switching times of the automatic transfer switch module is less than or equal to the preset switching times, the automatic transfer switch module is controlled to switch to the photovoltaic storage system for power supply.

[0075] Specifically, if the static voltage value is less than or equal to the preset switching voltage value or the number of daily switching of the automatic transfer switch module is greater than the preset number of switching times, it means that the charge state of the battery pack cannot meet the preset power supply demand or the number of daily switching of the automatic transfer switch module is too many. Long-term high-frequency switching may shorten the service life of the automatic transfer switch module. Therefore, it is necessary to control the number of daily switching of the automatic transfer switch module. At this time, it is necessary to continue to control the photovoltaic power supply to charge the battery pack with the first preset current; wherein, the preset switching voltage value can be set according to the static voltage value of a single battery cell in a fully charged state and the number of battery cells in series. For example, the preset switching voltage value U5=a*(2.2-0.05)=580.5V, at which time the charge state of the battery pack is about 40%.

[0076] If the static voltage value is greater than the preset switching voltage value and the number of daily switching of the automatic transfer switch module is less than or equal to the preset number of switching, it means that the charge state of the battery pack can meet the preset power supply demand and the number of daily switching of the automatic transfer switch module is small, and has not reached the upper limit of the daily switching number of a single day. At this time, the automatic transfer switch module can be controlled to switch to the photovoltaic storage system, and the load is powered by photovoltaics and the battery pack. By setting the preset switching voltage value and comparing the static voltage value with the preset switching voltage value, the automatic transfer switch module can be controlled to switch to the photovoltaic storage system when the battery pack reaches the preset power supply capacity, thereby improving the overall utilization rate of the photovoltaic storage system. For example, under normal circumstances, the maintenance-free time of the automatic transfer switch module is 5 years. During the maintenance-free time, the maintenance-free switching life of the automatic transfer switch module is 10,000 times, and the average number of daily switching times per day ranges from 2 to 5 times. If the average power P of the load of the project load =100kW, the maximum power of photovoltaic is P pv=250kW, the average sunshine duration is 4h, and the battery pack capacity P=324kWh. Since the energy generated by photovoltaic power every day is lower than the energy required by the daily load, the automatic transfer switch module must switch more than once a day. When the photovoltaic capacity is the largest, the output power of photovoltaic power is greater than the power required by the load. Therefore, when the voltage switched from the power grid to the photovoltaic storage system is too high, the energy utilization rate of the photovoltaic storage is low. And when the voltage value of the battery pack is too low, the number of switching times of the automatic transfer switch module will be too many, and the system cannot meet the expected design life. If the capacity of the battery pack is small, a lower value is selected in the preset switching voltage value, and when it encounters cloudy weather and insufficient light, the switching interval of the automatic transfer switch module is short, resulting in poor power supply quality of the load. Therefore, the preset switching voltage value setting can be set according to the switching interval time of the automatic transfer switch module, where the switching interval time of the automatic transfer switch module is greater than 1 hour. For example, if the battery capacity of the battery pack can power a load with an average power of 300kW-600kW, the preset switching voltage value can be set to the voltage value corresponding to the battery pack's state of charge of 40%; if the battery capacity of the battery pack can power a load with an average power of 1000kW, the preset switching voltage value can be set to the voltage value corresponding to the battery pack's state of charge of 20%.

[0077] Furthermore, if the voltage value is greater than or equal to the forbidden charging voltage value, the battery group is controlled to supply power to the load to the charging recovery voltage value, and the working state of the photovoltaic storage system is controlled according to the photovoltaic output power in the photovoltaic storage system, including:

[0078] If the voltage value is greater than or equal to the forbidden charging voltage value, the battery pack is controlled to supply power to the load to the charging recovery voltage value;

[0079] The output power of the photovoltaic power plant and the power consumption of the load are obtained, the energy state of the photovoltaic power plant is determined according to the output power of the photovoltaic power plant and the power consumption of the load, and the working state of the photovoltaic storage system is controlled according to the energy state of the photovoltaic power plant; wherein the energy state of the photovoltaic power plant includes an energy sufficient state and an energy insufficient state.

[0080] Specifically, when the automatic transfer switch module is controlled to switch to the photovoltaic storage system for power supply, if the voltage value of the battery pack is greater than or equal to the forbidden charging voltage value, the battery pack is controlled to supply power to the load alone. For example, the battery pack supplies power to the load with a discharge current corresponding to a discharge rate of 0.1C until the voltage value of the battery pack is a charging recovery voltage value. The charging recovery voltage value can be determined according to the number of battery cells in series. The charging recovery voltage value U6=2.1*a=567V, and the state of charge of the battery pack is 90%. After the voltage value of the battery pack drops to the charging recovery voltage value, the output power of the photovoltaic and the power consumption of the load are obtained, and the energy state of the photovoltaic is judged to be sufficient according to the output power of the photovoltaic and the power consumption of the load. For example, if the output power of the photovoltaic at the current moment is greater than the power consumption of the load, it means that the photovoltaic is in a sufficient energy state. If the output power of the photovoltaic at the current moment is less than or equal to the power consumption of the load, it means that the photovoltaic is in an insufficient energy state. If the photovoltaic is in a sufficient energy state, the photovoltaic is controlled to supply power to the load and the battery pack at the same time. If the photovoltaic is in an insufficient energy state, the photovoltaic and the battery pack are controlled to supply power to the load together.

[0081] Furthermore, the working state of the photovoltaic storage system is controlled according to the photovoltaic energy state, including:

[0082] If the photovoltaic power plant is in a state of sufficient energy, the photovoltaic power plant is controlled to supply power to the load and the battery pack at the same time;

[0083] If the photovoltaic power plant is in an energy-deficient state, the photovoltaic power plant and the battery group are controlled to jointly supply power to the load.

[0084] Specifically, if the photovoltaic power system is in a state of sufficient energy, it means that the photovoltaic power system can meet the power supply requirements of the load and the battery pack at the same time. At this time, the photovoltaic power system can be controlled to supply power to the load, and the remaining energy can be used to charge the battery pack at a first preset current, and when the voltage value of the battery pack is equal to the prohibited charging voltage value, switch to the battery pack to supply power to the load, and repeat this cycle; if the photovoltaic power system is in a state of insufficient energy, it means that the photovoltaic power system cannot meet the power supply requirements of the load. At this time, it is necessary to control the photovoltaic power system and the battery pack to supply power to the load together until the voltage value of the battery pack reaches the lower limit discharge voltage value, and when the voltage value of the battery pack is equal to the lower limit discharge voltage value, switch to the power grid to supply power to the load. Exemplarily, the lower limit discharge voltage value can be the prohibited discharge voltage value of the battery pack, wherein the prohibited discharge voltage value of the battery pack can be determined according to the number of battery cells in series. Exemplarily, the prohibited discharge voltage value U7=1.9*a=513V, and the state of charge of the battery pack is 10%.

[0085] Furthermore, the voltage value of the battery group in the photovoltaic storage system and the number of switching times of the automatic transfer switch module on the same day are obtained in real time, and the voltage value is compared with the forbidden charging voltage value of the battery group. Previously, it also includes:

[0086] It is determined whether the battery pack is in a calibrated state, and when the battery pack is in the calibrated state, the photovoltaic is controlled to charge the battery pack to a prohibited charging voltage value.

[0087] The calibrated state can be understood as a working state in which the photovoltaic system is controlled to fully charge each cell in the battery pack.

[0088] Specifically, after the photovoltaic storage system is controlled to start working, it is first determined whether the battery pack is in a calibrated state. If the battery pack is in a calibrated state, the grid is controlled to supply power to the load through the automatic transfer switch module, and the photovoltaic is controlled to charge the battery pack with the maximum current that the battery pack can accept, until the voltage value of the battery pack is equal to the forbidden charging voltage value or the battery pack is charged to a preset time, that is, the calibration of the battery pack is completed. By calibrating the battery pack, each cell in the battery pack is in a fully charged state, which extends the service life of the battery pack, and under the same state of charge, the calibrated battery pack supplies power to the load for a longer time. If the battery pack is not in a calibrated state, the grid is controlled to supply power to the load through the automatic transfer switch module, and the voltage value of the battery pack in the photovoltaic storage system and the number of switching times of the automatic transfer switch module on the same day are obtained in real time, so as to control the working state of the photovoltaic storage system according to the voltage value of the battery pack and the number of switching times of the automatic transfer switch module on the same day.

[0089] Furthermore, the voltage value of the battery group in the photovoltaic storage system and the number of switching times of the automatic transfer switch module on the same day are obtained in real time, and the voltage value is compared with the forbidden charging voltage value of the battery group. Previously, it also includes:

[0090] The number of battery cells in series, the allowable charging rate of the battery pack, and the total cell capacity in the battery pack are obtained in real time, and a preset comparison value is determined according to the number of battery cells in series, the allowable charging rate of the battery pack, and the total cell capacity in the battery pack; wherein the preset comparison value includes a forbidden charging voltage value, a long-term maximum charging current allowed for the battery pack in the equalization charging stage, and a preset switching voltage value.

[0091] Specifically, when the battery pack changes or the number of charging cells in the battery pack changes, the preset comparison value of the battery pack can be adjusted in time to ensure a more accurate photovoltaic storage system. Exemplarily, the preset comparison value includes a forbidden charging voltage value, a long-term maximum charging current allowed by the battery pack during the equalization charging stage, a preset switching voltage value, an equalization charging voltage limit, a floating charge voltage limit, a preset charging voltage, a charging recovery voltage value, a forbidden discharge voltage value, etc. The embodiments of the present invention do not limit this.

[0092] For example, Figure 2 is a flow chart of another control method of a photovoltaic storage system provided according to an embodiment of the present invention, with reference to Figure 2 The present invention provides a specific embodiment of a control method for a photovoltaic storage system, which is described in detail as follows:

[0093] S101, turn on the optical storage system and execute step S102;

[0094] S102, determining whether the battery pack is in a calibrated state, if not, executing step S103, if yes, executing step S201;

[0095] S103, control the power grid to supply power to the load, and execute step S104;

[0096] S104, determining whether the voltage value of the battery pack is greater than or equal to the forbidden charging voltage value, if not, executing step S105, if yes, executing step S301;

[0097] S105, the photovoltaic device charges the battery pack with the maximum current that the battery can accept, and detects the charging voltage value of the battery pack in real time, and executes step S106;

[0098] S106, determining whether the voltage value of the battery pack is greater than or equal to the preset charging voltage value and less than the forbidden charging voltage value, if not, executing step S107, if yes, executing step S108;

[0099] S107, determining whether the voltage value of the battery pack is greater than or equal to the forbidden charging voltage value, if not, executing step S105, if yes, executing step S301;

[0100] S108, perform current limiting processing on photovoltaic power generation, and determine whether the static voltage value of the battery pack is greater than the preset switching voltage and the number of daily switching of the automatic transfer switch module is less than or equal to the preset switching number. If not, execute step S105; if yes, execute step S301;

[0101] S201, control the power grid to supply power to the load, and execute step S202;

[0102] S202, the photovoltaic device charges the battery pack with the maximum current that the battery can accept, and executes step S203;

[0103] S203, determining whether the voltage value of the battery pack is equal to the forbidden charging voltage value or is charged to a preset time, if not, executing step S202, if yes, executing step S204;

[0104] S204, battery pack calibration is completed, and step S101 is executed;

[0105] S301, control the automatic transfer switch module to switch to the photovoltaic storage system to supply power to the load, and execute step S302;

[0106] S302, determining whether the voltage value of the battery pack is greater than or equal to the forbidden charging voltage value, if not, executing step S304, if yes, executing step S303;

[0107] S303, control the battery pack to supply power to the load alone to a charging recovery voltage value, and execute step S304;

[0108] S304, determine whether the photovoltaic power is in a sufficient energy state, if not, execute step S307, if yes, execute step S305;

[0109] S305, control the photovoltaic power supply to the load and the battery group, and execute step S306;

[0110] S306, determining whether the voltage value of the battery pack is greater than or equal to the forbidden charging voltage value, if not, executing step S305, if yes, executing step S303;

[0111] S307, control the photovoltaic and battery groups to jointly power the load, and execute step S308;

[0112] S308, determining whether the voltage value of the battery pack is less than or equal to the lower discharge voltage value, if not, executing step S307, and if so, executing step S301.

[0113] An embodiment of the present invention provides a control device for a photovoltaic storage system. Figure 3 is a schematic diagram of a control device for a photovoltaic storage system according to an embodiment of the present invention, with reference to Figure 3 , the control device 200 of the photovoltaic storage system includes:

[0114] The charging prohibition voltage comparison module 210 is used to obtain the voltage value of the battery group in the photovoltaic storage system and the number of switching times of the automatic transfer switch module on the same day in real time, and compare the voltage value with the charging prohibition voltage value of the battery group;

[0115] The battery pack charging module 220 is used to control the photovoltaic charging of the battery pack when the voltage value is less than the prohibited charging voltage, and control the working state of the photovoltaic storage system according to the voltage value and the number of switching times of the automatic transfer switch module on the same day;

[0116] The load power supply module 230 is used to control the battery group to supply power to the load to the charging recovery voltage value when the voltage value is greater than or equal to the charging prohibition voltage, and control the working state of the photovoltaic storage system according to the photovoltaic output power in the photovoltaic storage system.

[0117] Furthermore, the battery pack charging module 220 includes:

[0118] The battery pack charging submodule is used to control the photovoltaic to charge the battery pack with a first preset current when the voltage value is less than the prohibited charging voltage value, and obtain the charging voltage value of the battery pack in real time;

[0119] The working state determination submodule is used to control the working state of the photovoltaic storage system according to the voltage value and the number of switching times of the automatic transfer switch module on the same day when the charging voltage value is greater than or equal to the preset charging voltage value and less than the forbidden charging voltage value;

[0120] The load power supply submodule is used to control the automatic transfer switch module to switch to the photovoltaic storage system to supply power to the load when the charging voltage value is greater than or equal to the prohibited charging voltage value.

[0121] Furthermore, the working status determination submodule includes:

[0122] A current limiting processing unit, used to perform current limiting processing on the photovoltaic when the charging voltage value is greater than or equal to the preset charging voltage value and less than the forbidden charging voltage value, so as to keep the battery pack in a static state;

[0123] The working state determination unit is used to obtain the static voltage value of the battery group and control the working state of the photovoltaic storage system according to the static voltage value and the number of daily switching of the automatic transfer switch module.

[0124] Further, the working state determination unit includes:

[0125] The battery pack charging subunit is used to continue to control the photovoltaic to charge the battery pack with a first preset current when the static voltage value is less than or equal to the preset switching voltage value or the number of daily switching of the automatic transfer switch module is greater than the preset switching number;

[0126] The photovoltaic storage system power supply control subunit is used to control the automatic transfer switch module to switch to the photovoltaic storage system power supply when the static voltage is greater than the preset switching voltage and the number of daily switching of the automatic transfer switch module is less than or equal to the preset number of switching.

[0127] Furthermore, the load power supply module 230 includes:

[0128] The battery pack power supply unit is used to control the battery pack to supply power to the load to a charging recovery voltage value when the voltage value is greater than or equal to the charging prohibition voltage value;

[0129] The energy state determination unit is used to obtain the photovoltaic output power and the load power consumption, determine the photovoltaic energy state according to the photovoltaic output power and the load power consumption, and control the working state of the photovoltaic storage system according to the photovoltaic energy state; wherein the photovoltaic energy state includes an energy sufficient state and an energy insufficient state.

[0130] Further, the energy state determination unit includes:

[0131] A photovoltaic power supply sub-unit, used to control the photovoltaic power supply to supply power to the load and the battery group simultaneously when the photovoltaic power supply is in a sufficient energy state;

[0132] The common power supply sub-unit is used to control the photovoltaic and battery groups to jointly supply power to the load when the photovoltaic is in an energy-deficient state.

[0133] Furthermore, the control device 200 of the solar energy storage system further includes:

[0134] The calibration status judgment module is used to obtain the voltage value of the battery group in the photovoltaic storage system and the number of daily switching of the automatic transfer switch module in real time, and judge whether the battery group is in a calibrated state before comparing the voltage value with the prohibited charging voltage of the battery group. When the battery group is in the calibrated state, the photovoltaic power is controlled to charge the battery group to the prohibited charging voltage value.

[0135] Furthermore, the control device 200 of the solar energy storage system further includes:

[0136] A preset comparison value determination module is used to obtain in real time the voltage value of the battery pack in the photovoltaic storage system and the number of daily switching times of the automatic transfer switch module, and before comparing the voltage value with the forbidden charging voltage value of the battery pack, obtain in real time the number of battery cells in series, the allowable charging rate of the battery pack, and the total battery cell capacity in the battery pack, and determine the preset comparison value based on the number of battery cells in series, the allowable charging rate of the battery pack, and the total battery cell capacity in the battery pack; wherein the preset comparison value includes the forbidden charging voltage value, the long-term maximum charging current allowed by the battery pack in the equalization charging stage, and the preset switching voltage value.

[0137] The control device of the photovoltaic storage system provided in the embodiment of the present invention can execute the control method of the photovoltaic storage system provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0138] Figure 4 A schematic diagram of an electronic device that can be used to implement an embodiment of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device may also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0139] like Figure 4As shown, the electronic device 10 includes at least one processor 11, and a memory connected to the at least one processor 11, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., wherein the memory stores a computer program that can be executed by at least one processor, and the processor 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 to the random access memory (RAM) 13. In the RAM 13, various programs and data required for the operation of the electronic device 10 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other through a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0140] A number of components in the electronic device 10 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a disk, an optical disk, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0141] The processor 11 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as a control method for a light storage system.

[0142] In some embodiments, the control method of the optical storage system may be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or installed on the electronic device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the control method of the optical storage system described above may be performed. Alternatively, in other embodiments, the processor 11 may be configured to execute the control method of the optical storage system in any other appropriate manner (e.g., by means of firmware).

[0143] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0144] The computer program for implementing the control method of the optical storage system of the present invention can be written in any combination of one or more programming languages. These computer programs can be provided to a processor of a general-purpose computer, a special-purpose computer or other programmable data processing device, so that when the computer program is executed by the processor, the functions / operations specified in the flow chart and / or block diagram are implemented. The computer program can be executed entirely on the machine, partially on the machine, partially on the machine as a stand-alone software package and partially on a remote machine, or entirely on a remote machine or server.

[0145] In the context of the present invention, a computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in combination with an instruction execution system, device or equipment. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0146] To provide interaction with a user, the systems and techniques described herein may be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or trackball) through which the user can provide input to the electronic device. Other types of devices may also be used to provide interaction with the user; for example, the feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form (including acoustic input, voice input, or tactile input).

[0147] The systems and techniques described herein may be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0148] A computing system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The client and server relationship is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and VPS services.

[0149] An embodiment of the present invention provides a solar storage system. Figure 5 is a schematic diagram of a structure of a photovoltaic storage system provided according to an embodiment of the present invention, with reference to Figure 5 ,include:

[0150] Automatic transfer switch module 1, energy storage converter 2, DC combiner cabinet 3, battery pack 4, DC converter 5, multiple photovoltaic combiner boxes 6, multiple photovoltaic modules 7 and control cabinet;

[0151] A first end of the automatic transfer switch module 1 is connected to the power grid 8, a second end of the automatic transfer switch module 1 is connected to the load 9, and a third end of the automatic transfer switch module 1 is connected to a first end of the energy storage converter 2;

[0152] The second end of the energy storage converter 2 is connected to the first end of the DC combiner cabinet 3, the second end of the DC combiner cabinet 3 is connected to the first end of the DC converter 5, and the third end of the DC combiner cabinet 5 is connected to the battery pack 4;

[0153] The first end of each photovoltaic combiner box 6 is connected to the second end of the DC converter 5, and the second end of the photovoltaic combiner box 6 is connected to a plurality of photovoltaic modules 7;

[0154] The control cabinet is used to obtain the voltage value of the battery group 4 in the photovoltaic storage system and the number of switching times of the automatic transfer switch module 1 on the same day in real time, and compare the voltage value with the forbidden charging voltage value of the battery group; if the voltage value is less than the forbidden charging voltage value, the photovoltaic is controlled to charge the battery group, and the working state of the photovoltaic storage system is controlled according to the voltage value and the number of switching times of the automatic transfer switch module on the same day; if the voltage value is greater than or equal to the forbidden charging voltage value, the battery group is controlled to supply power to the load to the charging recovery voltage value, and the working state of the photovoltaic storage system is controlled according to the output power of the photovoltaic in the photovoltaic storage system.

[0155] The number of photovoltaic combiner boxes 6 and photovoltaic modules 7 can be set according to actual conditions, and the embodiment of the present invention does not limit this. Photovoltaic includes photovoltaic combiner boxes 6 and photovoltaic modules 7.

[0156] The photovoltaic storage system provided by the embodiment of the present invention obtains the voltage value of the battery group 4 and the number of daily switching of the automatic transfer switch module 1 in the photovoltaic storage system in real time, compares the voltage value with the forbidden charging voltage of the battery group 4, controls the photovoltaic to charge the battery group 4 when the voltage value is less than the forbidden charging voltage value, and controls the working state of the photovoltaic storage system according to the voltage value and the number of daily switching of the automatic transfer switch module 1; when the voltage value is greater than or equal to the forbidden charging voltage value, controls the battery group 4 to supply power to the load 9 to the charging recovery voltage value, and controls the working state of the photovoltaic storage system according to the photovoltaic output power in the photovoltaic storage system. Compared with the prior art in which the working state of the photovoltaic storage system is controlled according to the change of the charge state of the battery group 4 in the battery management system, the embodiment of the present invention can control the working state of the photovoltaic storage system according to the voltage value of the battery group 4 and the number of daily switching of the automatic transfer switch module 1 under the condition that the charge state of the battery group 4 cannot be accurately obtained, and limits the number of daily switching of the automatic transfer switch module 1 under the condition of ensuring normal power supply to the load 9, reduces the frequent switching of the automatic transfer switch module 1 due to extreme weather, thereby improving the service life of the photovoltaic storage system and ensuring the stability of the photovoltaic storage system. At the same time, the photovoltaic storage system provided by the embodiment of the present invention does not need to obtain the charge state of the battery group 4 according to the battery management system, which reduces the cost.

[0157] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0158] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A control method for a photovoltaic storage system, characterized in that: include: Acquire the voltage value of the battery group in the photovoltaic storage system and the number of switching times of the automatic transfer switch module on the same day in real time, and compare the voltage value with the forbidden charging voltage value of the battery group; If the voltage value is less than the prohibited charging voltage value, the photovoltaic is controlled to charge the battery group, and the working state of the photovoltaic storage system is controlled according to the voltage value and the number of switching times of the automatic transfer switch module on the same day; If the voltage value is greater than or equal to the charging prohibition voltage value, the battery pack is controlled to supply power to the load to the charging recovery voltage value, and the working state of the photovoltaic storage system is controlled according to the photovoltaic output power in the photovoltaic storage system.

2. The control method of the photovoltaic storage system according to claim 1, characterized in that: If the voltage value is less than the prohibition charging voltage value, the photovoltaic is controlled to charge the battery group, and the working state of the photovoltaic storage system is controlled according to the voltage value and the number of switching times of the automatic transfer switch module on the same day, including: If the voltage value is less than the forbidden charging voltage value, the photovoltaic is controlled to charge the battery pack with a first preset current, and the charging voltage value of the battery pack is obtained in real time; If the charging voltage value is greater than or equal to the preset charging voltage value and less than the forbidden charging voltage value, the working state of the photovoltaic storage system is controlled according to the voltage value and the number of switching times of the automatic transfer switch module on the same day; If the charging voltage value is greater than or equal to the charging prohibition voltage value, the automatic conversion switch module is controlled to switch to the photovoltaic storage system to supply power to the load.

3. The control method of the photovoltaic storage system according to claim 2, characterized in that: If the charging voltage value is greater than or equal to the preset charging voltage value and less than the forbidden charging voltage value, the working state of the photovoltaic storage system is controlled according to the voltage value and the number of daily switching of the automatic transfer switch module, including: If the charging voltage value is greater than or equal to the preset charging voltage value and less than the forbidden charging voltage value, current limiting processing is performed on the photovoltaic to keep the battery pack in a static state; The static voltage value of the battery pack is obtained, and the working state of the photovoltaic storage system is controlled according to the static voltage value and the number of daily switching of the automatic transfer switch module.

4. The control method of the photovoltaic storage system according to claim 3, characterized in that: Obtaining the static voltage value of the battery group, and controlling the working state of the photovoltaic storage system according to the static voltage value and the number of daily switching of the automatic transfer switch module, including: If the static voltage value is less than or equal to the preset switching voltage value or the number of daily switching of the automatic transfer switch module is greater than the preset number of switching, continue to control the photovoltaic to charge the battery group with a first preset current; If the static voltage is greater than the preset switching voltage and the number of daily switching times of the automatic transfer switch module is less than or equal to the preset switching times, the automatic transfer switch module is controlled to switch to the photovoltaic storage system for power supply.

5. The control method of the photovoltaic storage system according to claim 1, characterized in that: If the voltage value is greater than or equal to the charging prohibition voltage value, the battery group is controlled to supply power to the load to the charging recovery voltage value, and the working state of the photovoltaic storage system is controlled according to the photovoltaic output power in the photovoltaic storage system, including: If the voltage value is greater than or equal to the charging prohibition voltage value, controlling the battery pack to supply power to the load to the charging recovery voltage value; The output power of the photovoltaic system and the power consumption of the load are obtained, the energy state of the photovoltaic system is determined according to the output power of the photovoltaic system and the power consumption of the load, and the working state of the photovoltaic storage system is controlled according to the energy state of the photovoltaic system; wherein the energy state of the photovoltaic system includes an energy-sufficient state and an energy-deficient state.

6. The control method of the photovoltaic storage system according to claim 5, characterized in that: Controlling the working state of the photovoltaic storage system according to the photovoltaic energy state includes: If the photovoltaic is in a state of sufficient energy, controlling the photovoltaic to supply power to the load and the battery group at the same time; If the photovoltaic is in an energy-deficient state, the photovoltaic and the battery group are controlled to jointly supply power to the load.

7. The control method of the photovoltaic storage system according to claim 1, characterized in that: Real-time acquisition of the voltage value of the battery group in the photovoltaic storage system and the number of switching times of the automatic transfer switch module on the same day, and comparison of the voltage value with the forbidden charging voltage value of the battery group, which also includes: It is determined whether the battery pack is in a calibrated state, and when the battery pack is in the calibrated state, the photovoltaic is controlled to charge the battery pack to the forbidden charging voltage value.

8. The control method of the photovoltaic storage system according to claim 1, characterized in that: Real-time acquisition of the voltage value of the battery group in the photovoltaic storage system and the number of switching times of the automatic transfer switch module on the same day, and comparison of the voltage value with the forbidden charging voltage value of the battery group, which also includes: The number of battery cells connected in series, the allowable charging rate of the battery pack, and the total cell capacity in the battery pack are obtained in real time, and a preset comparison value of the battery pack is determined according to the number of battery cells connected in series, the allowable charging rate of the battery pack, and the total cell capacity in the battery pack; wherein the preset comparison value includes a forbidden charging voltage value, a long-term maximum charging current allowed for the battery pack in the equalization charging stage, and a preset switching voltage value.

9. A control device for a photovoltaic storage system, characterized in that: include: A charging prohibition voltage comparison module is used to obtain in real time the voltage value of the battery group in the photovoltaic storage system and the number of switching times of the automatic transfer switch module on the same day, and compare the voltage value with the charging prohibition voltage value of the battery group; A battery pack charging module, used to control photovoltaic charging of the battery pack when the voltage value is less than the prohibited charging voltage, and control the working state of the photovoltaic storage system according to the voltage value and the number of daily switching of the automatic transfer switch module; A load power supply module is used to control the battery pack to supply power to the load to a charging recovery voltage value when the voltage value is greater than or equal to the charging prohibition voltage, and to control the working state of the photovoltaic storage system according to the photovoltaic output power in the photovoltaic storage system.

10. A solar energy storage system, characterized in that: include: Automatic transfer switch module, energy storage converter, DC combiner, battery pack, DC converter, multiple photovoltaic combiner boxes, multiple photovoltaic modules and control cabinet; The first end of the automatic transfer switch module is connected to the power grid, the second end of the automatic transfer switch module is connected to the load, and the third end of the automatic transfer switch module is connected to the first end of the energy storage converter; The second end of the energy storage converter is connected to the first end of the DC combiner cabinet, the second end of the DC combiner cabinet is connected to the first end of the DC converter, and the third end of the DC combiner cabinet is connected to the battery pack; The first end of each photovoltaic combiner box is connected to the second end of the DC converter, and the second end of the photovoltaic combiner box is connected to a plurality of photovoltaic modules; The control cabinet is used to obtain the voltage value of the battery group in the photovoltaic storage system and the number of switching times of the automatic transfer switch module on the same day in real time, and compare the voltage value with the prohibited charging voltage value of the battery group; if the voltage value is less than the prohibited charging voltage value, the photovoltaic is controlled to charge the battery group, and the working state of the photovoltaic storage system is controlled according to the voltage value and the number of switching times of the automatic transfer switch module on the same day; if the voltage value is greater than or equal to the prohibited charging voltage value, the battery group is controlled to supply power to the load to the charging recovery voltage value, and the working state of the photovoltaic storage system is controlled according to the output power of the photovoltaic in the photovoltaic storage system.

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