Energy storage cabinet and energy storage system

Abstract

This invention relates to an energy storage cabinet and system in the field of power equipment technology, comprising a cabinet; the cabinet integrates an energy storage module, a power conversion module, a switching control module, a power distribution output module, and an energy manager, all of which are electrically connected to the energy manager; the power conversion module includes a bidirectional energy storage converter, a photovoltaic-specific inverter, and a voltage regulator; the switching control module has a built-in multi-mode switching control program and is electrically connected to the energy storage module, the power conversion module, and the mains power grid; the power distribution output module is used to connect to various electrical loads to achieve stable power output and overload protection. This invention achieves seamless adaptive switching between four modes: direct photovoltaic power supply, energy storage supplementary power supply, mains power switching, and off-grid independent power supply, and features high energy storage efficiency, strong power supply stability, wide adaptability to operating conditions, and high level of intelligence.

Description

Technical Field

[0001] This invention belongs to the field of power equipment technology, specifically relating to an energy storage cabinet and an energy storage system. Background Technology

[0002] With the widespread adoption of distributed photovoltaic (PV) energy, solar energy storage power supply systems have been widely applied in residential, commercial, and remote off-grid areas. Currently, energy storage cabinets have become the mainstream product form in this field. Given the diversity of commercial and industrial energy storage deployment scenarios, product design must meet requirements such as small footprint, reliable wall mounting, and support for parallel installation. Furthermore, product design must be adaptable to distributed deployment, ensuring flexible installation and convenient operation and maintenance. Because solar energy is an intermittent and fluctuating new energy source, it is greatly affected by sunlight intensity, weather, and diurnal temperature variations, resulting in unstable power generation. Traditional energy storage cabinets and systems have many technical shortcomings, such as the inability to perform tiered energy storage control based on real-time PV power generation, insufficient storage of surplus PV power on sunny days, ineffective charging during low-light periods leading to energy waste, and frequent charging and discharging of single battery packs causing battery aging and low energy storage utilization. Furthermore, traditional energy storage systems have a simple power supply switching logic, involving basic switching between photovoltaic power supply, energy storage power supply, and mains power supply. This results in problems such as switching lag, voltage fluctuations during the switching process, and short-term power outages. Overall, these systems suffer from low photovoltaic energy utilization and poor power supply reliability, failing to meet the demands for high-precision and uninterrupted energy storage power supply. Therefore, there is an urgent need for an energy storage cabinet and energy storage system to solve the aforementioned technical problems. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by providing an energy storage cabinet, including a cabinet body; the cabinet body integrates an energy storage module, an energy conversion module, a switching control module, a power distribution output module, and an energy manager, wherein the energy storage module, the energy conversion module, the switching control module, and the power distribution output module are all electrically connected to the energy manager; The energy storage module includes multiple energy storage battery packs; The power conversion module includes a bidirectional energy storage converter, a photovoltaic dedicated inverter, and a voltage regulation unit. The input terminal of the photovoltaic dedicated inverter is connected to an external photovoltaic module, and the output terminal of the photovoltaic dedicated inverter is connected to the bidirectional energy storage converter and the power distribution output module respectively. The bidirectional energy storage converter is electrically connected to the energy storage module to realize the AC / DC power conversion of the energy storage battery. The photovoltaic dedicated inverter converts the DC power collected by the external photovoltaic module into AC power adapted to the load. The bidirectional energy storage converter realizes the AC / DC conversion of the energy storage battery charging and discharging. The voltage regulation unit controls the output voltage fluctuation within ±1% to ensure the stability of the load power supply. The switching control module has a built-in multi-mode switching control program. The switching control module is electrically connected to the energy storage module, the power conversion module and the mains power grid respectively, and is used to adaptively switch between photovoltaic direct supply mode, energy storage charging mode, energy storage discharge supplementary supply mode, mains power complementary mode and off-grid independent power supply mode. The power distribution output module is used to connect to various electrical loads to achieve stable power output and overload protection.

[0004] Preferably, the cabinet is further equipped with a cooling unit and a fire-fighting unit connected to the energy manager. The cooling unit includes a liquid-cooled unit and an air-cooled unit, and the fire-fighting unit includes multiple smoke sensors, which are respectively installed in different positions of the cabinet and in the energy storage battery pack.

[0005] Preferably, the cabinet is divided into multiple compartments by partitions, and the energy storage module, power conversion module, switching control module, power distribution output module, cooling unit and fire-fighting unit are located in their respective compartments.

[0006] Preferably, the energy storage module is provided with multiple cooling plates in its corresponding compartment, and each cooling plate has a cooling channel. The cooling channel is connected to the liquid cooling unit through a medium inlet pipe and a medium outlet pipe, and the energy storage battery packs are respectively installed on the corresponding cooling plates.

[0007] Preferably, the cabinet is further provided with a status detection module electrically connected to the switching control module. The status detection module includes a photovoltaic power detection unit, a battery status detection unit, a grid parameter detection unit, and a load power detection unit. The status detection module is used to collect photovoltaic output power, energy storage battery pack charge and temperature, mains grid voltage and frequency, and load real-time power consumption parameters in real time, and transmit the detection data to the switching control module.

[0008] Preferably, the energy storage battery pack includes a main energy storage battery cluster and a backup energy storage battery cluster. The main energy storage battery cluster is used for daily photovoltaic power generation energy storage and conventional load power supply, while the backup energy storage battery cluster is used for emergency power supply under low photovoltaic light conditions and at night when there is no photovoltaic output.

[0009] Preferably, the energy storage battery pack is equipped with a charging control unit and a power balancing unit. The charging control unit is connected to the external photovoltaic module and adopts a hierarchical charging control logic, specifically: when the output power of the external photovoltaic module is greater than the real-time power consumption of the load, the excess energy is preferentially stored in the main energy storage battery cluster, and after the main energy storage battery cluster is fully charged, it automatically switches to the backup energy storage battery cluster for energy storage; when the photovoltaic output power is less than the load power consumption, energy storage charging is suspended, and the stored energy is preferentially used to supplement the load; when the photovoltaic light is weak and the power output is low, only a small amount of energy is supplied to the backup energy storage battery cluster to maintain emergency power reserves. The power balancing unit is used to monitor the individual cell voltage and power difference of the energy storage battery pack in real time. When the power difference between battery clusters exceeds a preset threshold, it automatically starts equalization charging to synchronize the power of the battery clusters, avoid overcharging and over-discharging of individual battery clusters, and improve the utilization rate of solar energy storage and battery life.

[0010] The switching control module has a built-in switching prediction algorithm, which can predict the switching requirements in advance based on the photovoltaic power change trend and the battery power decay rate, so as to achieve seamless switching of various power supply modes with zero interruption, a switching response time of ≤20ms, and no voltage fluctuations or power supply interruptions.

[0011] The mode switching logic of the switching control module includes grid-connected operation and off-grid operation: Under grid-connected conditions, the grid provides normal power supply, and photovoltaic direct power supply is given priority to the load. If there is excess photovoltaic power, energy storage is used. If there is insufficient photovoltaic power, energy storage is used to supplement the supply. After the energy storage is exhausted, the grid power supply is automatically and seamlessly switched to the grid power supply. In off-grid operation, if the grid fails or the grid parameters are abnormal, the mains power circuit will be automatically cut off and the system will switch to a photovoltaic + energy storage combined power supply mode. During the day, photovoltaic power will be given priority and the surplus energy storage will be used. At night, the energy storage battery pack will provide power independently.

[0012] The present invention also includes an energy storage system employing the above-described energy storage cabinet.

[0013] This invention also includes other components that enable the normal operation of an energy storage cabinet and energy storage system, all of which employ conventional techniques in the art. Furthermore, devices or components not limited in this invention, such as energy managers, power distribution output modules, energy storage battery packs, bidirectional energy storage converters, photovoltaic inverters, voltage regulators, smoke sensors, air-cooled units, and liquid-cooled units, all employ conventional techniques and equipment in the art.

[0014] The present invention has the following beneficial effects: 1. It adopts a modular integrated design with a reasonable cabinet layout, excellent heat dissipation and protection performance, high level of intelligence, convenient operation and maintenance, and can achieve long-term stable operation, reducing operation and maintenance costs.

[0015] 2. The design incorporates a multi-mode adaptive seamless switching logic. Through the cooperation of the switching control module and the status detection module, changes in photovoltaic, grid, and load conditions can be identified in advance, enabling uninterrupted switching between direct photovoltaic power supply, energy storage supplementary power supply, grid complementarity, and off-grid independent power supply. The switching response is fast, the voltage fluctuation is small, and there is no power interruption. This effectively solves the defects of traditional systems such as switching lag, power outages, and grid impacts, and significantly improves power supply stability.

[0016] 3. It is compatible with both grid-connected and off-grid operating conditions. In grid-connected mode, it achieves coordinated power supply from photovoltaic, energy storage and grid power to maximize the use of solar energy. In off-grid mode, it relies on a multi-level energy storage structure to ensure uninterrupted power supply day and night. It is suitable for use in various scenarios such as residential, industrial and commercial, and areas without grid power, and has strong versatility.

[0017] 4. The energy storage strategy can be dynamically adjusted according to the real-time photovoltaic power generation and load power consumption, so as to realize full storage of surplus power, suspension of energy storage when insufficient, and micro-supplementation of energy when the light is weak. This effectively solves the problems of energy waste and disordered charging and discharging in traditional photovoltaic energy storage, and improves the utilization rate of solar energy storage by more than 20%. At the same time, the power balancing unit ensures the consistency of battery cluster operation and extends the service life of energy storage batteries. Attached Figure Description

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0019] Figure 1 This is a schematic diagram of the structure of an energy storage cabinet and energy storage system according to an embodiment of the present invention; Figure 2 This is a schematic diagram of another structure of an energy storage cabinet and energy storage system in one embodiment.

[0020] In the diagram: 1. Cabinet; 2. Partition; 3. Cooling plate; 4. Energy storage battery pack; 5. Power distribution output module; 6. Switching control module; 7. Power conversion module; 8. Cooling unit; 9. Medium inlet pipe; 10. Medium outlet pipe; 11. Cabinet door; 12. Energy manager. Detailed Implementation

[0021] The present invention will now be clearly described with reference to the accompanying drawings and specific embodiments. This description is merely illustrative and is not intended to limit the scope of the invention. Any modifications, equivalent substitutions, or improvements made by those skilled in the art based on the embodiments of the present invention without inventive effort to obtain all other embodiments should be included within the scope of protection of the present invention.

[0022] Example 1 like Figure 1-2 As shown, the present invention provides an energy storage cabinet, including a cabinet body 1 and an openable cabinet door 11; the cabinet body 1 integrates an energy storage module, an energy conversion module 7, a switching control module 6, a power distribution output module 5 and an energy manager 12, and the energy storage module, the energy conversion module 7, the switching control module 6 and the power distribution output module 5 are all electrically connected to the energy manager 12; The energy storage module includes multiple energy storage battery packs 4; The power conversion module 7 includes a bidirectional energy storage converter, a photovoltaic dedicated inverter, and a voltage regulation unit. The input terminal of the photovoltaic dedicated inverter is connected to an external photovoltaic module, and the output terminal of the photovoltaic dedicated inverter is connected to the bidirectional energy storage converter and the power distribution output module 5, respectively. The bidirectional energy storage converter is electrically connected to the energy storage module and is used to realize the AC / DC power conversion of the energy storage battery. The photovoltaic dedicated inverter converts the DC power collected by the external photovoltaic module into AC power adapted to the load. The bidirectional energy storage converter realizes the AC / DC conversion of the energy storage battery charging and discharging. The voltage regulation unit controls the output voltage fluctuation within ±1% to ensure the stability of the load power supply. The switching control module 6 has a built-in multi-mode switching control program. The switching control module 6 is electrically connected to the energy storage module, the power conversion module 7 and the mains power grid respectively, and is used to adaptively switch between photovoltaic direct supply mode, energy storage charging mode, energy storage discharge supplementary supply mode, mains power complementary mode and off-grid independent power supply mode. The power distribution output module 5 is used to connect to various electrical loads to achieve stable power output and overload protection.

[0023] The cabinet 1 is also equipped with a cooling unit 8 and a fire-fighting unit connected to the energy manager 12. The cooling unit 8 includes a liquid cooling unit and an air cooling unit. The fire-fighting unit includes multiple smoke sensors, which are respectively installed in different positions of the cabinet 1 and in the energy storage battery pack 4.

[0024] The cabinet 1 is divided into multiple compartments by partitions 2, and the energy storage module, power conversion module 7, switching control module 6, power distribution output module 5, cooling unit 8 and fire-fighting unit are located in their respective compartments.

[0025] The energy storage module is equipped with multiple cooling plates 3 in its corresponding compartment. Each cooling plate 3 has a cooling channel, which is connected to the liquid cooling unit through a medium inlet pipe 9 and a medium outlet pipe 10. The energy storage battery packs 4 are respectively installed on the corresponding cooling plates 3.

[0026] The cabinet 1 is also equipped with a status detection module electrically connected to the switching control module 6. The status detection module includes a photovoltaic power detection unit, a battery status detection unit, a grid parameter detection unit, and a load power detection unit. The status detection module is used to collect photovoltaic output power, energy storage battery pack 4 power and temperature, mains grid voltage and frequency, and load real-time power consumption parameters in real time, and transmit the detection data to the switching control module 6.

[0027] The energy storage battery pack 4 includes a main energy storage battery cluster and a backup energy storage battery cluster. The main energy storage battery cluster is used for daily photovoltaic power generation energy storage and conventional load power supply, while the backup energy storage battery cluster is used for emergency power supply in low photovoltaic light conditions and when there is no photovoltaic output at night.

[0028] The energy storage battery pack 4 is equipped with a charging control unit and a power balancing unit. The charging control unit is connected to the external photovoltaic module and adopts a hierarchical charging control logic. Specifically, when the output power of the external photovoltaic module is greater than the real-time power consumption of the load, the excess energy is preferentially stored in the main energy storage battery cluster. After the main energy storage battery cluster is fully charged, it automatically switches to the backup energy storage battery cluster for energy storage. When the photovoltaic output power is less than the load power consumption, energy storage charging is suspended, and the stored energy is preferentially used to supplement the load. When the photovoltaic light is weak and the power output is low, only a small amount of energy is supplied to the backup energy storage battery cluster to maintain emergency power reserves. The power balancing unit is used to monitor the individual cell voltage and power difference of the energy storage battery pack 4 in real time. When the power difference between battery clusters exceeds a preset threshold, it automatically starts equalization charging to synchronize the power of the battery clusters, avoid overcharging and over-discharging of individual battery clusters, and improve the utilization rate of solar energy storage and battery life.

[0029] The switching control module 6 has a built-in switching prediction algorithm, which can predict the switching requirements in advance based on the photovoltaic power change trend and the battery power decay rate, so as to achieve seamless switching of various power supply modes with zero interruption, a switching response time of ≤20ms, and no voltage fluctuations or power supply interruptions.

[0030] The mode switching logic of the switching control module 6 includes grid-connected operation and off-grid operation: Under grid-connected conditions, the grid provides normal power supply, and photovoltaic direct power supply is given priority to the load. If there is excess photovoltaic power, energy storage is used. If there is insufficient photovoltaic power, energy storage is used to supplement the supply. After the energy storage is exhausted, the grid power supply is automatically and seamlessly switched to the grid power supply. In off-grid operation, if the grid fails or the grid parameters are abnormal, the mains power circuit will be automatically cut off and the photovoltaic + energy storage combined power supply mode will be switched. During the day, photovoltaic power supply will be prioritized and the surplus energy storage will be used. At night, the energy storage battery pack 4 will provide independent power supply.

[0031] In this embodiment, the photovoltaic output power, energy storage battery SOC value, mains power grid status, and load power consumption data are continuously collected through the status detection module. The switching control module determines the three operating conditions of photovoltaic power generation as surplus, insufficient, and weak based on the detection data, and executes the corresponding full energy storage, on-demand energy storage, and micro-supplementation strategies. Combined with the grid connection status, it automatically switches between photovoltaic direct supply, energy storage supplementation, grid power complementation, and off-grid energy storage power supply modes. The energy storage battery pack status is monitored in real time by the power balancing unit, and the power of each battery cluster is dynamically balanced to ensure the stable operation of the energy storage system.

[0032] Example 2 An energy storage system employs an energy storage cabinet as described in Example 1. The cabinet is a sealed metal enclosure, and the cooling unit can stabilize the battery operating temperature within the optimal operating range of 25-35℃. In the energy storage module, the main energy storage battery cluster uses a large-capacity lithium iron phosphate battery pack to meet the daily photovoltaic energy storage and conventional load power supply needs, while the backup energy storage battery cluster uses a high-rate battery pack specifically for emergency power supply and low-light energy storage. The charging control unit receives photovoltaic power and load power data from the status detection module in real time and executes a tiered energy storage strategy: when there is surplus photovoltaic power under strong sunlight on sunny days, it is preferentially stored in the main energy storage battery cluster, and automatically switches to the backup energy storage battery cluster after full charging; when there is insufficient photovoltaic power under cloudy days with weak sunlight, energy storage is stopped, and the stored energy is preferentially used to supplement the load; under low-light conditions in the early morning and evening, only a small amount of energy is supplied to the backup energy storage battery cluster to retain emergency power. The power balancing unit collects the voltage and power data of each individual battery cluster every 10 seconds. When the power difference between clusters is ≥5%, the balancing charging is automatically started to achieve power synchronization.

[0033] In the power conversion module, the photovoltaic inverter converts the DC power collected by the photovoltaic module into AC power adapted to the load, the bidirectional energy storage converter realizes the AC-DC conversion of the energy storage battery charging and discharging, and the voltage regulation unit controls the output voltage fluctuation within ±1% to ensure the stability of the load power supply.

[0034] The status detection module collects photovoltaic output power, battery SOC value, battery temperature, mains voltage frequency, and load real-time power consumption around the clock, with a collection frequency of 100ms / time, and transmits the data to the intelligent switching control module in real time.

[0035] The switching control module is the core control unit, with a built-in STM32 core processor and adaptive switching algorithm. The specific switching conditions are as follows: Under normal grid connection conditions: When the grid voltage and frequency are normal, and the photovoltaic power is greater than or equal to the load power consumption, the system executes the photovoltaic direct supply + surplus energy storage mode, where the photovoltaic directly supplies power to the load, and the excess energy is stored in the energy storage battery pack; when the photovoltaic power is less than the load power consumption, the energy storage battery pack automatically discharges to supplement the photovoltaic power supply; when the energy storage battery SOC is less than or equal to 20%, it automatically and seamlessly switches to grid power supply, while the photovoltaic continues to supplement the energy storage.

[0036] Off-grid fault conditions: When the mains power fails, the voltage is abnormal, or the frequency deviation exceeds the standard, the system will cut off the mains power circuit within 20ms and switch to off-grid power supply mode; when there is sufficient sunlight during the day, the photovoltaic power supply will be prioritized, and the surplus energy will be stored; when there is no photovoltaic output at night, the main and backup energy storage battery groups will work together to supply power until the photovoltaic power generation is restored or the mains power is restored to normal.

[0037] The energy storage system workflow of this embodiment is as follows: external photovoltaic modules collect solar energy and convert it into electrical energy. After processing by the power conversion module, the energy is either directly supplied to the load or stored in the energy storage module according to the operating conditions. The status detection module monitors the operating parameters of the entire system in real time, and the switching control module dynamically adjusts the energy storage strategy and power supply mode. The energy storage system can be connected to a remote monitoring terminal to synchronize system data in real time, support users to remotely view, adjust parameters, and receive fault warnings, and achieve fully intelligent operation.

[0038] The embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An energy storage cabinet, comprising a cabinet body; characterized in that: The cabinet integrates an energy storage module, a power conversion module, a switching control module, a power distribution output module, and an energy manager. The energy storage module, the power conversion module, the switching control module, and the power distribution output module are all electrically connected to the energy manager. The energy storage module includes multiple energy storage battery packs; The power conversion module includes a bidirectional energy storage converter, a photovoltaic dedicated inverter, and a voltage regulation unit. The input terminal of the photovoltaic dedicated inverter is connected to an external photovoltaic module, and the output terminal of the photovoltaic dedicated inverter is connected to the bidirectional energy storage converter and the power distribution output module respectively. The bidirectional energy storage converter is electrically connected to the energy storage module to realize the AC / DC power conversion of the energy storage battery. The switching control module is electrically connected to the energy storage module, the power conversion module and the mains grid respectively, and is used to adaptively switch between photovoltaic direct supply mode, energy storage charging mode, energy storage discharge supplementary supply mode, mains grid complementary mode and off-grid independent power supply mode. The power distribution output module is used to connect to various electrical loads to achieve stable power output and overload protection.

2. The energy storage cabinet according to claim 1, characterized in that: The cabinet is also equipped with a cooling unit and a fire-fighting unit connected to the energy manager. The cooling unit includes a liquid-cooled unit and an air-cooled unit, and the fire-fighting unit includes multiple smoke sensors, which are respectively installed in different positions in the cabinet and in the energy storage battery pack.

3. The energy storage cabinet according to claim 2, characterized in that: The cabinet is divided into multiple compartments by partitions, and the energy storage module, power conversion module, switching control module, power distribution output module, cooling unit and fire-fighting unit are located in their respective compartments.

4. The energy storage cabinet according to claim 3, characterized in that: The energy storage module is equipped with multiple cooling plates inside its compartment. Each cooling plate has a cooling channel, which is connected to the liquid cooling unit via a medium inlet pipe and a medium outlet pipe. The energy storage battery packs are respectively mounted on the corresponding cooling plates.

5. The energy storage cabinet according to claim 1, characterized in that: The cabinet is also equipped with a status detection module electrically connected to the switching control module. The status detection module includes a photovoltaic power detection unit, a battery status detection unit, a grid parameter detection unit, and a load power detection unit. The status detection module is used to collect photovoltaic output power, energy storage battery pack charge and temperature, mains grid voltage and frequency, and load real-time power consumption parameters in real time, and transmit the detection data to the switching control module.

6. The energy storage cabinet according to claim 1, characterized in that: The energy storage battery pack includes a main energy storage battery cluster and a backup energy storage battery cluster. The main energy storage battery cluster is used for daily photovoltaic power generation energy storage and conventional load power supply, while the backup energy storage battery cluster is used for emergency power supply under low photovoltaic light conditions and at night when there is no photovoltaic output.

7. An energy storage cabinet according to claim 6, characterized in that: The energy storage battery pack is equipped with a charging control unit and a power balancing unit, and the charging control unit is connected to an external photovoltaic module. The power balancing unit is used to monitor the individual cell voltage and power difference of the energy storage battery pack in real time.

8. An energy storage system, characterized in that: An energy storage cabinet as described in any one of claims 1-7 is used.

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